Merging upstream version 1.69.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

223 files changed, 4270 insertions, 1869 deletions

diff --git a/tests/mir-opt/76803_regression.encode.SimplifyBranchSame.diff b/tests/mir-opt/76803_regression.encode.SimplifyBranchSame.diff
deleted file mode 100644
index 9780332d8..000000000
--- a/tests/mir-opt/76803_regression.encode.SimplifyBranchSame.diff
+++ /dev/null
@@ -1,29 +0,0 @@
-- // MIR for `encode` before SimplifyBranchSame
-+ // MIR for `encode` after SimplifyBranchSame
-  
-  fn encode(_1: Type) -> Type {
-      debug v => _1;                       // in scope 0 at $DIR/76803_regression.rs:+0:15: +0:16
-      let mut _0: Type;                    // return place in scope 0 at $DIR/76803_regression.rs:+0:27: +0:31
-      let mut _2: isize;                   // in scope 0 at $DIR/76803_regression.rs:+2:9: +2:16
-  
-      bb0: {
-          _2 = discriminant(_1);           // scope 0 at $DIR/76803_regression.rs:+1:11: +1:12
-          switchInt(move _2) -> [0: bb2, otherwise: bb1]; // scope 0 at $DIR/76803_regression.rs:+1:5: +1:12
-      }
-  
-      bb1: {
-          _0 = move _1;                    // scope 0 at $DIR/76803_regression.rs:+3:14: +3:15
-          goto -> bb3;                     // scope 0 at $DIR/76803_regression.rs:+3:14: +3:15
-      }
-  
-      bb2: {
-          Deinit(_0);                      // scope 0 at $DIR/76803_regression.rs:+2:20: +2:27
-          discriminant(_0) = 1;            // scope 0 at $DIR/76803_regression.rs:+2:20: +2:27
-          goto -> bb3;                     // scope 0 at $DIR/76803_regression.rs:+2:20: +2:27
-      }
-  
-      bb3: {
-          return;                          // scope 0 at $DIR/76803_regression.rs:+5:2: +5:2
-      }
-  }
-  
diff --git a/tests/mir-opt/76803_regression.rs b/tests/mir-opt/76803_regression.rs
deleted file mode 100644
index 05dc3c978..000000000
--- a/tests/mir-opt/76803_regression.rs
+++ /dev/null
@@ -1,19 +0,0 @@
-// compile-flags: -Z mir-opt-level=1
-// EMIT_MIR 76803_regression.encode.SimplifyBranchSame.diff
-
-#[derive(Debug, Eq, PartialEq)]
-pub enum Type {
-    A,
-    B,
-}
-
-pub fn encode(v: Type) -> Type {
-    match v {
-        Type::A => Type::B,
-        _ => v,
-    }
-}
-
-fn main() {
-    assert_eq!(Type::B, encode(Type::A));
-}
diff --git a/tests/mir-opt/building/async_await.a-{closure#0}.generator_resume.0.mir b/tests/mir-opt/building/async_await.a-{closure#0}.generator_resume.0.mir
index 2a7f90fe9..accb504c0 100644
--- a/tests/mir-opt/building/async_await.a-{closure#0}.generator_resume.0.mir
+++ b/tests/mir-opt/building/async_await.a-{closure#0}.generator_resume.0.mir
@@ -24,9 +24,7 @@ fn a::{closure#0}(_1: Pin<&mut [async fn body@$DIR/async_await.rs:11:14: 11:16]>
     bb1: {
         _4 = move _2;                    // scope 0 at $DIR/async_await.rs:+0:14: +0:16
         _3 = const ();                   // scope 0 at $DIR/async_await.rs:+0:14: +0:16
-        Deinit(_0);                      // scope 0 at $DIR/async_await.rs:+0:16: +0:16
-        ((_0 as Ready).0: ()) = move _3; // scope 0 at $DIR/async_await.rs:+0:16: +0:16
-        discriminant(_0) = 0;            // scope 0 at $DIR/async_await.rs:+0:16: +0:16
+        _0 = Poll::<()>::Ready(move _3); // scope 0 at $DIR/async_await.rs:+0:16: +0:16
         discriminant((*(_1.0: &mut [async fn body@$DIR/async_await.rs:11:14: 11:16]))) = 1; // scope 0 at $DIR/async_await.rs:+0:16: +0:16
         return;                          // scope 0 at $DIR/async_await.rs:+0:16: +0:16
     }
diff --git a/tests/mir-opt/building/async_await.b-{closure#0}.generator_resume.0.mir b/tests/mir-opt/building/async_await.b-{closure#0}.generator_resume.0.mir
index 05edc4797..ad4e5c6fc 100644
--- a/tests/mir-opt/building/async_await.b-{closure#0}.generator_resume.0.mir
+++ b/tests/mir-opt/building/async_await.b-{closure#0}.generator_resume.0.mir
@@ -1,8 +1,22 @@
 // MIR for `b::{closure#0}` 0 generator_resume
 /* generator_layout = GeneratorLayout {
     field_tys: {
-        _0: impl std::future::Future<Output = ()>,
-        _1: impl std::future::Future<Output = ()>,
+        _0: GeneratorSavedTy {
+            ty: impl std::future::Future<Output = ()>,
+            source_info: SourceInfo {
+                span: $DIR/async_await.rs:15:8: 15:14 (#9),
+                scope: scope[0],
+            },
+            ignore_for_traits: false,
+        },
+        _1: GeneratorSavedTy {
+            ty: impl std::future::Future<Output = ()>,
+            source_info: SourceInfo {
+                span: $DIR/async_await.rs:16:8: 16:14 (#12),
+                scope: scope[0],
+            },
+            ignore_for_traits: false,
+        },
     },
     variant_fields: {
         Unresumed(0): [],
@@ -153,8 +167,7 @@ fn b::{closure#0}(_1: Pin<&mut [async fn body@$DIR/async_await.rs:14:18: 17:2]>,
         StorageLive(_19);                // scope 1 at $DIR/async_await.rs:+1:8: +1:14
         StorageLive(_20);                // scope 1 at $DIR/async_await.rs:+1:8: +1:14
         _20 = ();                        // scope 1 at $DIR/async_await.rs:+1:8: +1:14
-        Deinit(_0);                      // scope 1 at $DIR/async_await.rs:+1:8: +1:14
-        discriminant(_0) = 1;            // scope 1 at $DIR/async_await.rs:+1:8: +1:14
+        _0 = Poll::<()>::Pending;        // scope 1 at $DIR/async_await.rs:+1:8: +1:14
         discriminant((*(_1.0: &mut [async fn body@$DIR/async_await.rs:14:18: 17:2]))) = 3; // scope 1 at $DIR/async_await.rs:+1:8: +1:14
         return;                          // scope 1 at $DIR/async_await.rs:+1:8: +1:14
     }
@@ -262,8 +275,7 @@ fn b::{closure#0}(_1: Pin<&mut [async fn body@$DIR/async_await.rs:14:18: 17:2]>,
         StorageLive(_35);                // scope 4 at $DIR/async_await.rs:+2:8: +2:14
         StorageLive(_36);                // scope 4 at $DIR/async_await.rs:+2:8: +2:14
         _36 = ();                        // scope 4 at $DIR/async_await.rs:+2:8: +2:14
-        Deinit(_0);                      // scope 4 at $DIR/async_await.rs:+2:8: +2:14
-        discriminant(_0) = 1;            // scope 4 at $DIR/async_await.rs:+2:8: +2:14
+        _0 = Poll::<()>::Pending;        // scope 4 at $DIR/async_await.rs:+2:8: +2:14
         discriminant((*(_1.0: &mut [async fn body@$DIR/async_await.rs:14:18: 17:2]))) = 4; // scope 4 at $DIR/async_await.rs:+2:8: +2:14
         return;                          // scope 4 at $DIR/async_await.rs:+2:8: +2:14
     }
@@ -303,9 +315,7 @@ fn b::{closure#0}(_1: Pin<&mut [async fn body@$DIR/async_await.rs:14:18: 17:2]>,
     }
 
     bb26: {
-        Deinit(_0);                      // scope 0 at $DIR/async_await.rs:+3:2: +3:2
-        ((_0 as Ready).0: ()) = move _37; // scope 0 at $DIR/async_await.rs:+3:2: +3:2
-        discriminant(_0) = 0;            // scope 0 at $DIR/async_await.rs:+3:2: +3:2
+        _0 = Poll::<()>::Ready(move _37); // scope 0 at $DIR/async_await.rs:+3:2: +3:2
         discriminant((*(_1.0: &mut [async fn body@$DIR/async_await.rs:14:18: 17:2]))) = 1; // scope 0 at $DIR/async_await.rs:+3:2: +3:2
         return;                          // scope 0 at $DIR/async_await.rs:+3:2: +3:2
     }
diff --git a/tests/mir-opt/building/custom/arrays.arrays.built.after.mir b/tests/mir-opt/building/custom/arrays.arrays.built.after.mir
new file mode 100644
index 000000000..4c9212728
--- /dev/null
+++ b/tests/mir-opt/building/custom/arrays.arrays.built.after.mir
@@ -0,0 +1,14 @@
+// MIR for `arrays` after built
+
+fn arrays() -> usize {
+    let mut _0: usize;                   // return place in scope 0 at $DIR/arrays.rs:+0:32: +0:37
+    let mut _1: [i32; C];                // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+    let mut _2: usize;                   // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+
+    bb0: {
+        _1 = [const 5_i32; C];           // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+        _2 = Len(_1);                    // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+        _0 = _2;                         // scope 0 at $DIR/arrays.rs:+4:9: +4:16
+        return;                          // scope 0 at $DIR/arrays.rs:+5:9: +5:17
+    }
+}
diff --git a/tests/mir-opt/building/custom/arrays.rs b/tests/mir-opt/building/custom/arrays.rs
new file mode 100644
index 000000000..8e0a1fd7a
--- /dev/null
+++ b/tests/mir-opt/building/custom/arrays.rs
@@ -0,0 +1,19 @@
+#![feature(custom_mir, core_intrinsics, inline_const)]
+
+extern crate core;
+use core::intrinsics::mir::*;
+
+// EMIT_MIR arrays.arrays.built.after.mir
+#[custom_mir(dialect = "built")]
+fn arrays<const C: usize>() -> usize {
+    mir!({
+        let x = [5_i32; C];
+        let c = Len(x);
+        RET = c;
+        Return()
+    })
+}
+
+fn main() {
+    assert_eq!(arrays::<20>(), 20);
+}
diff --git a/tests/mir-opt/building/custom/enums.rs b/tests/mir-opt/building/custom/enums.rs
index e5cd45637..eca5b792e 100644
--- a/tests/mir-opt/building/custom/enums.rs
+++ b/tests/mir-opt/building/custom/enums.rs
@@ -86,6 +86,7 @@ fn switch_option_repr(option: Bool) -> bool {
 #[custom_mir(dialect = "runtime", phase = "initial")]
 fn set_discr(option: &mut Option<()>) {
     mir!({
+        Deinit(*option);
         SetDiscriminant(*option, 0);
         Return()
     })
diff --git a/tests/mir-opt/building/custom/enums.set_discr.built.after.mir b/tests/mir-opt/building/custom/enums.set_discr.built.after.mir
index 7de9ed098..6d0747365 100644
--- a/tests/mir-opt/building/custom/enums.set_discr.built.after.mir
+++ b/tests/mir-opt/building/custom/enums.set_discr.built.after.mir
@@ -4,7 +4,8 @@ fn set_discr(_1: &mut Option<()>) -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/enums.rs:+0:39: +0:39
 
     bb0: {
-        discriminant((*_1)) = 0;         // scope 0 at $DIR/enums.rs:+2:9: +2:36
-        return;                          // scope 0 at $DIR/enums.rs:+3:9: +3:17
+        Deinit((*_1));                   // scope 0 at $DIR/enums.rs:+2:9: +2:24
+        discriminant((*_1)) = 0;         // scope 0 at $DIR/enums.rs:+3:9: +3:36
+        return;                          // scope 0 at $DIR/enums.rs:+4:9: +4:17
     }
 }
diff --git a/tests/mir-opt/building/custom/operators.f.built.after.mir b/tests/mir-opt/building/custom/operators.f.built.after.mir
new file mode 100644
index 000000000..cb43d5e6e
--- /dev/null
+++ b/tests/mir-opt/building/custom/operators.f.built.after.mir
@@ -0,0 +1,30 @@
+// MIR for `f` after built
+
+fn f(_1: i32, _2: bool) -> i32 {
+    let mut _0: i32;                     // return place in scope 0 at $DIR/operators.rs:+0:30: +0:33
+    let mut _3: (i32, bool);             // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+
+    bb0: {
+        _1 = Neg(_1);                    // scope 0 at $DIR/operators.rs:+2:9: +2:15
+        _2 = Not(_2);                    // scope 0 at $DIR/operators.rs:+3:9: +3:15
+        _1 = Add(_1, _1);                // scope 0 at $DIR/operators.rs:+4:9: +4:18
+        _1 = Sub(_1, _1);                // scope 0 at $DIR/operators.rs:+5:9: +5:18
+        _1 = Mul(_1, _1);                // scope 0 at $DIR/operators.rs:+6:9: +6:18
+        _1 = Div(_1, _1);                // scope 0 at $DIR/operators.rs:+7:9: +7:18
+        _1 = Rem(_1, _1);                // scope 0 at $DIR/operators.rs:+8:9: +8:18
+        _1 = BitXor(_1, _1);             // scope 0 at $DIR/operators.rs:+9:9: +9:18
+        _1 = BitAnd(_1, _1);             // scope 0 at $DIR/operators.rs:+10:9: +10:18
+        _1 = Shl(_1, _1);                // scope 0 at $DIR/operators.rs:+11:9: +11:19
+        _1 = Shr(_1, _1);                // scope 0 at $DIR/operators.rs:+12:9: +12:19
+        _2 = Eq(_1, _1);                 // scope 0 at $DIR/operators.rs:+13:9: +13:19
+        _2 = Lt(_1, _1);                 // scope 0 at $DIR/operators.rs:+14:9: +14:18
+        _2 = Le(_1, _1);                 // scope 0 at $DIR/operators.rs:+15:9: +15:19
+        _2 = Ge(_1, _1);                 // scope 0 at $DIR/operators.rs:+16:9: +16:19
+        _2 = Gt(_1, _1);                 // scope 0 at $DIR/operators.rs:+17:9: +17:18
+        _3 = CheckedAdd(_1, _1);         // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+        _2 = (_3.1: bool);               // scope 0 at $DIR/operators.rs:+19:9: +19:18
+        _1 = (_3.0: i32);                // scope 0 at $DIR/operators.rs:+20:9: +20:18
+        _0 = _1;                         // scope 0 at $DIR/operators.rs:+21:9: +21:16
+        return;                          // scope 0 at $DIR/operators.rs:+22:9: +22:17
+    }
+}
diff --git a/tests/mir-opt/building/custom/operators.rs b/tests/mir-opt/building/custom/operators.rs
new file mode 100644
index 000000000..db7a48317
--- /dev/null
+++ b/tests/mir-opt/building/custom/operators.rs
@@ -0,0 +1,31 @@
+// compile-flags: --crate-type=lib
+#![feature(custom_mir, core_intrinsics, inline_const)]
+use std::intrinsics::mir::*;
+
+// EMIT_MIR operators.f.built.after.mir
+#[custom_mir(dialect = "built")]
+pub fn f(a: i32, b: bool) -> i32 {
+    mir!({
+        a = -a;
+        b = !b;
+        a = a + a;
+        a = a - a;
+        a = a * a;
+        a = a / a;
+        a = a % a;
+        a = a ^ a;
+        a = a & a;
+        a = a << a;
+        a = a >> a;
+        b = a == a;
+        b = a < a;
+        b = a <= a;
+        b = a >= a;
+        b = a > a;
+        let res = Checked(a + a);
+        b = res.1;
+        a = res.0;
+        RET = a;
+        Return()
+    })
+}
diff --git a/tests/mir-opt/casts.redundant.InstCombine.diff b/tests/mir-opt/casts.redundant.InstCombine.diff
new file mode 100644
index 000000000..528a8e5a9
--- /dev/null
+++ b/tests/mir-opt/casts.redundant.InstCombine.diff
@@ -0,0 +1,25 @@
+- // MIR for `redundant` before InstCombine
++ // MIR for `redundant` after InstCombine
+  
+  fn redundant(_1: *const &u8) -> *const &u8 {
+      debug x => _1;                       // in scope 0 at $DIR/casts.rs:+0:30: +0:31
+      let mut _0: *const &u8;              // return place in scope 0 at $DIR/casts.rs:+0:51: +0:64
+      let mut _2: *const &u8;              // in scope 0 at $DIR/casts.rs:+1:5: +1:55
+      let mut _3: *const &u8;              // in scope 0 at $DIR/casts.rs:+1:36: +1:37
+      scope 1 (inlined generic_cast::<&u8, &u8>) { // at $DIR/casts.rs:6:5: 6:38
+          debug x => _3;                   // in scope 1 at $DIR/casts.rs:10:23: 10:24
+      }
+  
+      bb0: {
+          StorageLive(_2);                 // scope 0 at $DIR/casts.rs:+1:5: +1:55
+          StorageLive(_3);                 // scope 0 at $DIR/casts.rs:+1:36: +1:37
+          _3 = _1;                         // scope 0 at $DIR/casts.rs:+1:36: +1:37
+-         _2 = _3 as *const &u8 (PtrToPtr); // scope 1 at $DIR/casts.rs:11:5: 11:18
++         _2 = _3;                         // scope 1 at $DIR/casts.rs:11:5: 11:18
+          StorageDead(_3);                 // scope 0 at $DIR/casts.rs:+1:37: +1:38
+          _0 = _2;                         // scope 0 at $DIR/casts.rs:+1:5: +1:55
+          StorageDead(_2);                 // scope 0 at $DIR/casts.rs:+2:1: +2:2
+          return;                          // scope 0 at $DIR/casts.rs:+2:2: +2:2
+      }
+  }
+  
diff --git a/tests/mir-opt/casts.redundant.PreCodegen.after.mir b/tests/mir-opt/casts.redundant.PreCodegen.after.mir
new file mode 100644
index 000000000..21a470ea3
--- /dev/null
+++ b/tests/mir-opt/casts.redundant.PreCodegen.after.mir
@@ -0,0 +1,14 @@
+// MIR for `redundant` after PreCodegen
+
+fn redundant(_1: *const &u8) -> *const &u8 {
+    debug x => _1;                       // in scope 0 at $DIR/casts.rs:+0:30: +0:31
+    let mut _0: *const &u8;              // return place in scope 0 at $DIR/casts.rs:+0:51: +0:64
+    scope 1 (inlined generic_cast::<&u8, &u8>) { // at $DIR/casts.rs:6:5: 6:38
+        debug x => _1;                   // in scope 1 at $DIR/casts.rs:10:23: 10:24
+    }
+
+    bb0: {
+        _0 = _1;                         // scope 0 at $DIR/casts.rs:+1:5: +1:55
+        return;                          // scope 0 at $DIR/casts.rs:+2:2: +2:2
+    }
+}
diff --git a/tests/mir-opt/casts.roundtrip.PreCodegen.after.mir b/tests/mir-opt/casts.roundtrip.PreCodegen.after.mir
new file mode 100644
index 000000000..0c793984c
--- /dev/null
+++ b/tests/mir-opt/casts.roundtrip.PreCodegen.after.mir
@@ -0,0 +1,15 @@
+// MIR for `roundtrip` after PreCodegen
+
+fn roundtrip(_1: *const u8) -> *const u8 {
+    debug x => _1;                       // in scope 0 at $DIR/casts.rs:+0:18: +0:19
+    let mut _0: *const u8;               // return place in scope 0 at $DIR/casts.rs:+0:35: +0:44
+    let mut _2: *mut u8;                 // in scope 0 at $DIR/casts.rs:+1:5: +1:17
+
+    bb0: {
+        StorageLive(_2);                 // scope 0 at $DIR/casts.rs:+1:5: +1:17
+        _2 = _1 as *mut u8 (PtrToPtr);   // scope 0 at $DIR/casts.rs:+1:5: +1:17
+        _0 = move _2 as *const u8 (Pointer(MutToConstPointer)); // scope 0 at $DIR/casts.rs:+1:5: +1:17
+        StorageDead(_2);                 // scope 0 at $DIR/casts.rs:+1:16: +1:17
+        return;                          // scope 0 at $DIR/casts.rs:+2:2: +2:2
+    }
+}
diff --git a/tests/mir-opt/casts.rs b/tests/mir-opt/casts.rs
new file mode 100644
index 000000000..259c462da
--- /dev/null
+++ b/tests/mir-opt/casts.rs
@@ -0,0 +1,17 @@
+#![crate_type = "lib"]
+
+// EMIT_MIR casts.redundant.InstCombine.diff
+// EMIT_MIR casts.redundant.PreCodegen.after.mir
+pub fn redundant<'a, 'b: 'a>(x: *const &'a u8) -> *const &'a u8 {
+    generic_cast::<&'a u8, &'b u8>(x) as *const &'a u8
+}
+
+#[inline]
+fn generic_cast<T, U>(x: *const T) -> *const U {
+    x as *const U
+}
+
+// EMIT_MIR casts.roundtrip.PreCodegen.after.mir
+pub fn roundtrip(x: *const u8) -> *const u8 {
+    x as *mut u8 as *const u8
+}
diff --git a/tests/mir-opt/combine_clone_of_primitives.{impl#0}-clone.InstCombine.diff b/tests/mir-opt/combine_clone_of_primitives.{impl#0}-clone.InstCombine.diff
index 6f01553ee..20b0fb964 100644
--- a/tests/mir-opt/combine_clone_of_primitives.{impl#0}-clone.InstCombine.diff
+++ b/tests/mir-opt/combine_clone_of_primitives.{impl#0}-clone.InstCombine.diff
@@ -61,10 +61,7 @@
   
       bb3: {
           StorageDead(_9);                 // scope 0 at $DIR/combine_clone_of_primitives.rs:10:15: 10:16
-          Deinit(_0);                      // scope 0 at $DIR/combine_clone_of_primitives.rs:+0:10: +0:15
-          (_0.0: T) = move _2;             // scope 0 at $DIR/combine_clone_of_primitives.rs:+0:10: +0:15
-          (_0.1: u64) = move _5;           // scope 0 at $DIR/combine_clone_of_primitives.rs:+0:10: +0:15
-          (_0.2: [f32; 3]) = move _8;      // scope 0 at $DIR/combine_clone_of_primitives.rs:+0:10: +0:15
+          _0 = MyThing::<T> { v: move _2, i: move _5, a: move _8 }; // scope 0 at $DIR/combine_clone_of_primitives.rs:+0:10: +0:15
           StorageDead(_8);                 // scope 0 at $DIR/combine_clone_of_primitives.rs:+0:14: +0:15
           StorageDead(_5);                 // scope 0 at $DIR/combine_clone_of_primitives.rs:+0:14: +0:15
           StorageDead(_2);                 // scope 0 at $DIR/combine_clone_of_primitives.rs:+0:14: +0:15
diff --git a/tests/mir-opt/const_allocation.main.ConstProp.after.32bit.mir b/tests/mir-opt/const_allocation.main.ConstProp.after.32bit.mir
index 6140fc52f..9b69f79c2 100644
--- a/tests/mir-opt/const_allocation.main.ConstProp.after.32bit.mir
+++ b/tests/mir-opt/const_allocation.main.ConstProp.after.32bit.mir
@@ -26,17 +26,17 @@ alloc1 (static: FOO, size: 8, align: 4) {
 
 alloc18 (size: 48, align: 4) {
     0x00 │ 00 00 00 00 __ __ __ __ ╾─alloc5──╼ 00 00 00 00 │ ....░░░░╾──╼....
-    0x10 │ 00 00 00 00 __ __ __ __ ╾─alloc9──╼ 02 00 00 00 │ ....░░░░╾──╼....
-    0x20 │ 01 00 00 00 2a 00 00 00 ╾─alloc14─╼ 03 00 00 00 │ ....*...╾──╼....
+    0x10 │ 00 00 00 00 __ __ __ __ ╾─alloc8──╼ 02 00 00 00 │ ....░░░░╾──╼....
+    0x20 │ 01 00 00 00 2a 00 00 00 ╾─alloc13─╼ 03 00 00 00 │ ....*...╾──╼....
 }
 
 alloc5 (size: 0, align: 4) {}
 
-alloc9 (size: 16, align: 4) {
-    ╾─alloc8──╼ 03 00 00 00 ╾─alloc10─╼ 03 00 00 00 │ ╾──╼....╾──╼....
+alloc8 (size: 16, align: 4) {
+    ╾─alloc9──╼ 03 00 00 00 ╾─alloc10─╼ 03 00 00 00 │ ╾──╼....╾──╼....
 }
 
-alloc8 (size: 3, align: 1) {
+alloc9 (size: 3, align: 1) {
     66 6f 6f                                        │ foo
 }
 
@@ -44,12 +44,12 @@ alloc10 (size: 3, align: 1) {
     62 61 72                                        │ bar
 }
 
-alloc14 (size: 24, align: 4) {
-    0x00 │ ╾─alloc13─╼ 03 00 00 00 ╾─alloc15─╼ 03 00 00 00 │ ╾──╼....╾──╼....
+alloc13 (size: 24, align: 4) {
+    0x00 │ ╾─alloc14─╼ 03 00 00 00 ╾─alloc15─╼ 03 00 00 00 │ ╾──╼....╾──╼....
     0x10 │ ╾─alloc16─╼ 04 00 00 00                         │ ╾──╼....
 }
 
-alloc13 (size: 3, align: 1) {
+alloc14 (size: 3, align: 1) {
     6d 65 68                                        │ meh
 }
 
diff --git a/tests/mir-opt/const_allocation.main.ConstProp.after.64bit.mir b/tests/mir-opt/const_allocation.main.ConstProp.after.64bit.mir
index b2ed23c68..d0f196e72 100644
--- a/tests/mir-opt/const_allocation.main.ConstProp.after.64bit.mir
+++ b/tests/mir-opt/const_allocation.main.ConstProp.after.64bit.mir
@@ -27,19 +27,19 @@ alloc1 (static: FOO, size: 16, align: 8) {
 alloc18 (size: 72, align: 8) {
     0x00 │ 00 00 00 00 __ __ __ __ ╾───────alloc5────────╼ │ ....░░░░╾──────╼
     0x10 │ 00 00 00 00 00 00 00 00 00 00 00 00 __ __ __ __ │ ............░░░░
-    0x20 │ ╾───────alloc9────────╼ 02 00 00 00 00 00 00 00 │ ╾──────╼........
-    0x30 │ 01 00 00 00 2a 00 00 00 ╾───────alloc14───────╼ │ ....*...╾──────╼
+    0x20 │ ╾───────alloc8────────╼ 02 00 00 00 00 00 00 00 │ ╾──────╼........
+    0x30 │ 01 00 00 00 2a 00 00 00 ╾───────alloc13───────╼ │ ....*...╾──────╼
     0x40 │ 03 00 00 00 00 00 00 00                         │ ........
 }
 
 alloc5 (size: 0, align: 8) {}
 
-alloc9 (size: 32, align: 8) {
-    0x00 │ ╾───────alloc8────────╼ 03 00 00 00 00 00 00 00 │ ╾──────╼........
+alloc8 (size: 32, align: 8) {
+    0x00 │ ╾───────alloc9────────╼ 03 00 00 00 00 00 00 00 │ ╾──────╼........
     0x10 │ ╾───────alloc10───────╼ 03 00 00 00 00 00 00 00 │ ╾──────╼........
 }
 
-alloc8 (size: 3, align: 1) {
+alloc9 (size: 3, align: 1) {
     66 6f 6f                                        │ foo
 }
 
@@ -47,13 +47,13 @@ alloc10 (size: 3, align: 1) {
     62 61 72                                        │ bar
 }
 
-alloc14 (size: 48, align: 8) {
-    0x00 │ ╾───────alloc13───────╼ 03 00 00 00 00 00 00 00 │ ╾──────╼........
+alloc13 (size: 48, align: 8) {
+    0x00 │ ╾───────alloc14───────╼ 03 00 00 00 00 00 00 00 │ ╾──────╼........
     0x10 │ ╾───────alloc15───────╼ 03 00 00 00 00 00 00 00 │ ╾──────╼........
     0x20 │ ╾───────alloc16───────╼ 04 00 00 00 00 00 00 00 │ ╾──────╼........
 }
 
-alloc13 (size: 3, align: 1) {
+alloc14 (size: 3, align: 1) {
     6d 65 68                                        │ meh
 }
 
diff --git a/tests/mir-opt/const_debuginfo.main.ConstDebugInfo.diff b/tests/mir-opt/const_debuginfo.main.ConstDebugInfo.diff
index dd548adde..f1f53a481 100644
--- a/tests/mir-opt/const_debuginfo.main.ConstDebugInfo.diff
+++ b/tests/mir-opt/const_debuginfo.main.ConstDebugInfo.diff
@@ -56,25 +56,13 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/const_debuginfo.rs:+1:9: +1:10
           _1 = const 1_u8;                 // scope 0 at $DIR/const_debuginfo.rs:+1:13: +1:16
-          StorageLive(_2);                 // scope 1 at $DIR/const_debuginfo.rs:+2:9: +2:10
           _2 = const 2_u8;                 // scope 1 at $DIR/const_debuginfo.rs:+2:13: +2:16
-          StorageLive(_3);                 // scope 2 at $DIR/const_debuginfo.rs:+3:9: +3:10
           _3 = const 3_u8;                 // scope 2 at $DIR/const_debuginfo.rs:+3:13: +3:16
           StorageLive(_4);                 // scope 3 at $DIR/const_debuginfo.rs:+4:9: +4:12
           StorageLive(_5);                 // scope 3 at $DIR/const_debuginfo.rs:+4:15: +4:20
-          StorageLive(_6);                 // scope 3 at $DIR/const_debuginfo.rs:+4:15: +4:16
-          _6 = const 1_u8;                 // scope 3 at $DIR/const_debuginfo.rs:+4:15: +4:16
-          StorageLive(_7);                 // scope 3 at $DIR/const_debuginfo.rs:+4:19: +4:20
-          _7 = const 2_u8;                 // scope 3 at $DIR/const_debuginfo.rs:+4:19: +4:20
           _5 = const 3_u8;                 // scope 3 at $DIR/const_debuginfo.rs:+4:15: +4:20
-          StorageDead(_7);                 // scope 3 at $DIR/const_debuginfo.rs:+4:19: +4:20
-          StorageDead(_6);                 // scope 3 at $DIR/const_debuginfo.rs:+4:19: +4:20
-          StorageLive(_8);                 // scope 3 at $DIR/const_debuginfo.rs:+4:23: +4:24
-          _8 = const 3_u8;                 // scope 3 at $DIR/const_debuginfo.rs:+4:23: +4:24
           _4 = const 6_u8;                 // scope 3 at $DIR/const_debuginfo.rs:+4:15: +4:24
-          StorageDead(_8);                 // scope 3 at $DIR/const_debuginfo.rs:+4:23: +4:24
           StorageDead(_5);                 // scope 3 at $DIR/const_debuginfo.rs:+4:23: +4:24
           StorageLive(_9);                 // scope 4 at $DIR/const_debuginfo.rs:+6:9: +6:10
           _9 = const "hello, world!";      // scope 4 at $DIR/const_debuginfo.rs:+6:13: +6:28
@@ -84,42 +72,22 @@
           StorageLive(_14);                // scope 5 at $DIR/const_debuginfo.rs:+8:9: +8:10
           StorageLive(_15);                // scope 5 at $DIR/const_debuginfo.rs:+8:9: +8:10
           StorageLive(_16);                // scope 5 at $DIR/const_debuginfo.rs:+8:9: +8:10
-          Deinit(_14);                     // scope 5 at $DIR/const_debuginfo.rs:+8:13: +8:34
-          Deinit(_15);                     // scope 5 at $DIR/const_debuginfo.rs:+8:13: +8:34
-          Deinit(_16);                     // scope 5 at $DIR/const_debuginfo.rs:+8:13: +8:34
           _14 = const true;                // scope 5 at $DIR/const_debuginfo.rs:+8:13: +8:34
           _15 = const false;               // scope 5 at $DIR/const_debuginfo.rs:+8:13: +8:34
           _16 = const 123_u32;             // scope 5 at $DIR/const_debuginfo.rs:+8:13: +8:34
           StorageLive(_10);                // scope 6 at $DIR/const_debuginfo.rs:+10:9: +10:10
-          Deinit(_10);                     // scope 6 at $DIR/const_debuginfo.rs:+10:13: +10:24
-          ((_10 as Some).0: u16) = const 99_u16; // scope 6 at $DIR/const_debuginfo.rs:+10:13: +10:24
-          discriminant(_10) = 1;           // scope 6 at $DIR/const_debuginfo.rs:+10:13: +10:24
-          StorageLive(_17);                // scope 7 at $DIR/const_debuginfo.rs:+12:9: +12:10
-          StorageLive(_18);                // scope 7 at $DIR/const_debuginfo.rs:+12:9: +12:10
-          Deinit(_17);                     // scope 7 at $DIR/const_debuginfo.rs:+12:13: +12:35
-          Deinit(_18);                     // scope 7 at $DIR/const_debuginfo.rs:+12:13: +12:35
+          _10 = Option::<u16>::Some(const 99_u16); // scope 6 at $DIR/const_debuginfo.rs:+10:13: +10:24
           _17 = const 32_u32;              // scope 7 at $DIR/const_debuginfo.rs:+12:13: +12:35
           _18 = const 32_u32;              // scope 7 at $DIR/const_debuginfo.rs:+12:13: +12:35
           StorageLive(_11);                // scope 8 at $DIR/const_debuginfo.rs:+13:9: +13:10
-          StorageLive(_12);                // scope 8 at $DIR/const_debuginfo.rs:+13:13: +13:16
-          _12 = const 32_u32;              // scope 8 at $DIR/const_debuginfo.rs:+13:13: +13:16
-          StorageLive(_13);                // scope 8 at $DIR/const_debuginfo.rs:+13:19: +13:22
-          _13 = const 32_u32;              // scope 8 at $DIR/const_debuginfo.rs:+13:19: +13:22
           _11 = const 64_u32;              // scope 8 at $DIR/const_debuginfo.rs:+13:13: +13:22
-          StorageDead(_13);                // scope 8 at $DIR/const_debuginfo.rs:+13:21: +13:22
-          StorageDead(_12);                // scope 8 at $DIR/const_debuginfo.rs:+13:21: +13:22
           StorageDead(_11);                // scope 8 at $DIR/const_debuginfo.rs:+14:1: +14:2
-          StorageDead(_17);                // scope 7 at $DIR/const_debuginfo.rs:+14:1: +14:2
-          StorageDead(_18);                // scope 7 at $DIR/const_debuginfo.rs:+14:1: +14:2
           StorageDead(_10);                // scope 6 at $DIR/const_debuginfo.rs:+14:1: +14:2
           StorageDead(_14);                // scope 5 at $DIR/const_debuginfo.rs:+14:1: +14:2
           StorageDead(_15);                // scope 5 at $DIR/const_debuginfo.rs:+14:1: +14:2
           StorageDead(_16);                // scope 5 at $DIR/const_debuginfo.rs:+14:1: +14:2
           StorageDead(_9);                 // scope 4 at $DIR/const_debuginfo.rs:+14:1: +14:2
           StorageDead(_4);                 // scope 3 at $DIR/const_debuginfo.rs:+14:1: +14:2
-          StorageDead(_3);                 // scope 2 at $DIR/const_debuginfo.rs:+14:1: +14:2
-          StorageDead(_2);                 // scope 1 at $DIR/const_debuginfo.rs:+14:1: +14:2
-          StorageDead(_1);                 // scope 0 at $DIR/const_debuginfo.rs:+14:1: +14:2
           return;                          // scope 0 at $DIR/const_debuginfo.rs:+14:2: +14:2
       }
   }
diff --git a/tests/mir-opt/const_goto_storage.match_nested_if.ConstGoto.diff b/tests/mir-opt/const_goto_storage.match_nested_if.ConstGoto.diff
index f54577259..4dc98f856 100644
--- a/tests/mir-opt/const_goto_storage.match_nested_if.ConstGoto.diff
+++ b/tests/mir-opt/const_goto_storage.match_nested_if.ConstGoto.diff
@@ -17,7 +17,7 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/const_goto_storage.rs:+1:9: +1:12
 -         StorageLive(_2);                 // scope 0 at $DIR/const_goto_storage.rs:+1:21: +1:23
--         Deinit(_2);                      // scope 0 at $DIR/const_goto_storage.rs:+1:21: +1:23
+-         _2 = ();                         // scope 0 at $DIR/const_goto_storage.rs:+1:21: +1:23
 -         StorageLive(_3);                 // scope 0 at $DIR/const_goto_storage.rs:+2:15: +6:10
 -         StorageLive(_4);                 // scope 0 at $DIR/const_goto_storage.rs:+2:18: +2:76
 -         StorageLive(_5);                 // scope 0 at $DIR/const_goto_storage.rs:+2:21: +2:52
diff --git a/tests/mir-opt/const_prop/aggregate.foo.ConstProp.diff b/tests/mir-opt/const_prop/aggregate.foo.ConstProp.diff
new file mode 100644
index 000000000..6ac460db8
--- /dev/null
+++ b/tests/mir-opt/const_prop/aggregate.foo.ConstProp.diff
@@ -0,0 +1,55 @@
+- // MIR for `foo` before ConstProp
++ // MIR for `foo` after ConstProp
+  
+  fn foo(_1: u8) -> () {
+      debug x => _1;                       // in scope 0 at $DIR/aggregate.rs:+0:8: +0:9
+      let mut _0: ();                      // return place in scope 0 at $DIR/aggregate.rs:+0:15: +0:15
+      let _2: i32;                         // in scope 0 at $DIR/aggregate.rs:+2:9: +2:14
+      let mut _3: i32;                     // in scope 0 at $DIR/aggregate.rs:+2:17: +2:25
+      let mut _4: (i32, u8);               // in scope 0 at $DIR/aggregate.rs:+2:17: +2:23
+      let mut _5: u8;                      // in scope 0 at $DIR/aggregate.rs:+2:21: +2:22
+      let mut _7: i32;                     // in scope 0 at $DIR/aggregate.rs:+3:18: +3:26
+      let mut _8: (u8, i32);               // in scope 0 at $DIR/aggregate.rs:+3:18: +3:24
+      let mut _9: u8;                      // in scope 0 at $DIR/aggregate.rs:+3:19: +3:20
+      scope 1 {
+          debug first => _2;               // in scope 1 at $DIR/aggregate.rs:+2:9: +2:14
+          let _6: i32;                     // in scope 1 at $DIR/aggregate.rs:+3:9: +3:15
+          scope 2 {
+              debug second => _6;          // in scope 2 at $DIR/aggregate.rs:+3:9: +3:15
+          }
+      }
+  
+      bb0: {
+          StorageLive(_2);                 // scope 0 at $DIR/aggregate.rs:+2:9: +2:14
+          StorageLive(_3);                 // scope 0 at $DIR/aggregate.rs:+2:17: +2:25
+          StorageLive(_4);                 // scope 0 at $DIR/aggregate.rs:+2:17: +2:23
+          StorageLive(_5);                 // scope 0 at $DIR/aggregate.rs:+2:21: +2:22
+          _5 = _1;                         // scope 0 at $DIR/aggregate.rs:+2:21: +2:22
+          _4 = (const 0_i32, move _5);     // scope 0 at $DIR/aggregate.rs:+2:17: +2:23
+          StorageDead(_5);                 // scope 0 at $DIR/aggregate.rs:+2:22: +2:23
+-         _3 = (_4.0: i32);                // scope 0 at $DIR/aggregate.rs:+2:17: +2:25
+-         _2 = Add(move _3, const 1_i32);  // scope 0 at $DIR/aggregate.rs:+2:17: +2:29
++         _3 = const 0_i32;                // scope 0 at $DIR/aggregate.rs:+2:17: +2:25
++         _2 = const 1_i32;                // scope 0 at $DIR/aggregate.rs:+2:17: +2:29
+          StorageDead(_3);                 // scope 0 at $DIR/aggregate.rs:+2:28: +2:29
+          StorageDead(_4);                 // scope 0 at $DIR/aggregate.rs:+2:29: +2:30
+          StorageLive(_6);                 // scope 1 at $DIR/aggregate.rs:+3:9: +3:15
+          StorageLive(_7);                 // scope 1 at $DIR/aggregate.rs:+3:18: +3:26
+          StorageLive(_8);                 // scope 1 at $DIR/aggregate.rs:+3:18: +3:24
+          StorageLive(_9);                 // scope 1 at $DIR/aggregate.rs:+3:19: +3:20
+          _9 = _1;                         // scope 1 at $DIR/aggregate.rs:+3:19: +3:20
+          _8 = (move _9, const 1_i32);     // scope 1 at $DIR/aggregate.rs:+3:18: +3:24
+          StorageDead(_9);                 // scope 1 at $DIR/aggregate.rs:+3:23: +3:24
+-         _7 = (_8.1: i32);                // scope 1 at $DIR/aggregate.rs:+3:18: +3:26
+-         _6 = Add(move _7, const 2_i32);  // scope 1 at $DIR/aggregate.rs:+3:18: +3:30
++         _7 = const 1_i32;                // scope 1 at $DIR/aggregate.rs:+3:18: +3:26
++         _6 = const 3_i32;                // scope 1 at $DIR/aggregate.rs:+3:18: +3:30
+          StorageDead(_7);                 // scope 1 at $DIR/aggregate.rs:+3:29: +3:30
+          StorageDead(_8);                 // scope 1 at $DIR/aggregate.rs:+3:30: +3:31
+          _0 = const ();                   // scope 0 at $DIR/aggregate.rs:+0:15: +4:2
+          StorageDead(_6);                 // scope 1 at $DIR/aggregate.rs:+4:1: +4:2
+          StorageDead(_2);                 // scope 0 at $DIR/aggregate.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/aggregate.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/const_prop/aggregate.foo.PreCodegen.after.mir b/tests/mir-opt/const_prop/aggregate.foo.PreCodegen.after.mir
new file mode 100644
index 000000000..2ef6d74e5
--- /dev/null
+++ b/tests/mir-opt/const_prop/aggregate.foo.PreCodegen.after.mir
@@ -0,0 +1,49 @@
+// MIR for `foo` after PreCodegen
+
+fn foo(_1: u8) -> () {
+    debug x => _1;                       // in scope 0 at $DIR/aggregate.rs:+0:8: +0:9
+    let mut _0: ();                      // return place in scope 0 at $DIR/aggregate.rs:+0:15: +0:15
+    let _2: i32;                         // in scope 0 at $DIR/aggregate.rs:+2:9: +2:14
+    let mut _3: i32;                     // in scope 0 at $DIR/aggregate.rs:+2:17: +2:25
+    let mut _4: (i32, u8);               // in scope 0 at $DIR/aggregate.rs:+2:17: +2:23
+    let mut _5: u8;                      // in scope 0 at $DIR/aggregate.rs:+2:21: +2:22
+    let mut _7: i32;                     // in scope 0 at $DIR/aggregate.rs:+3:18: +3:26
+    let mut _8: (u8, i32);               // in scope 0 at $DIR/aggregate.rs:+3:18: +3:24
+    let mut _9: u8;                      // in scope 0 at $DIR/aggregate.rs:+3:19: +3:20
+    scope 1 {
+        debug first => _2;               // in scope 1 at $DIR/aggregate.rs:+2:9: +2:14
+        let _6: i32;                     // in scope 1 at $DIR/aggregate.rs:+3:9: +3:15
+        scope 2 {
+            debug second => _6;          // in scope 2 at $DIR/aggregate.rs:+3:9: +3:15
+        }
+    }
+
+    bb0: {
+        StorageLive(_2);                 // scope 0 at $DIR/aggregate.rs:+2:9: +2:14
+        StorageLive(_3);                 // scope 0 at $DIR/aggregate.rs:+2:17: +2:25
+        StorageLive(_4);                 // scope 0 at $DIR/aggregate.rs:+2:17: +2:23
+        StorageLive(_5);                 // scope 0 at $DIR/aggregate.rs:+2:21: +2:22
+        _5 = _1;                         // scope 0 at $DIR/aggregate.rs:+2:21: +2:22
+        _4 = (const 0_i32, move _5);     // scope 0 at $DIR/aggregate.rs:+2:17: +2:23
+        StorageDead(_5);                 // scope 0 at $DIR/aggregate.rs:+2:22: +2:23
+        _3 = const 0_i32;                // scope 0 at $DIR/aggregate.rs:+2:17: +2:25
+        _2 = const 1_i32;                // scope 0 at $DIR/aggregate.rs:+2:17: +2:29
+        StorageDead(_3);                 // scope 0 at $DIR/aggregate.rs:+2:28: +2:29
+        StorageDead(_4);                 // scope 0 at $DIR/aggregate.rs:+2:29: +2:30
+        StorageLive(_6);                 // scope 1 at $DIR/aggregate.rs:+3:9: +3:15
+        StorageLive(_7);                 // scope 1 at $DIR/aggregate.rs:+3:18: +3:26
+        StorageLive(_8);                 // scope 1 at $DIR/aggregate.rs:+3:18: +3:24
+        StorageLive(_9);                 // scope 1 at $DIR/aggregate.rs:+3:19: +3:20
+        _9 = _1;                         // scope 1 at $DIR/aggregate.rs:+3:19: +3:20
+        _8 = (move _9, const 1_i32);     // scope 1 at $DIR/aggregate.rs:+3:18: +3:24
+        StorageDead(_9);                 // scope 1 at $DIR/aggregate.rs:+3:23: +3:24
+        _7 = const 1_i32;                // scope 1 at $DIR/aggregate.rs:+3:18: +3:26
+        _6 = const 3_i32;                // scope 1 at $DIR/aggregate.rs:+3:18: +3:30
+        StorageDead(_7);                 // scope 1 at $DIR/aggregate.rs:+3:29: +3:30
+        StorageDead(_8);                 // scope 1 at $DIR/aggregate.rs:+3:30: +3:31
+        _0 = const ();                   // scope 0 at $DIR/aggregate.rs:+0:15: +4:2
+        StorageDead(_6);                 // scope 1 at $DIR/aggregate.rs:+4:1: +4:2
+        StorageDead(_2);                 // scope 0 at $DIR/aggregate.rs:+4:1: +4:2
+        return;                          // scope 0 at $DIR/aggregate.rs:+4:2: +4:2
+    }
+}
diff --git a/tests/mir-opt/const_prop/aggregate.main.ConstProp.diff b/tests/mir-opt/const_prop/aggregate.main.ConstProp.diff
index 04378dbf3..f6e58955b 100644
--- a/tests/mir-opt/const_prop/aggregate.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/aggregate.main.ConstProp.diff
@@ -3,9 +3,11 @@
   
   fn main() -> () {
       let mut _0: ();                      // return place in scope 0 at $DIR/aggregate.rs:+0:11: +0:11
-      let _1: i32;                         // in scope 0 at $DIR/aggregate.rs:+1:9: +1:10
-      let mut _2: i32;                     // in scope 0 at $DIR/aggregate.rs:+1:13: +1:24
-      let mut _3: (i32, i32, i32);         // in scope 0 at $DIR/aggregate.rs:+1:13: +1:22
+      let _1: u8;                          // in scope 0 at $DIR/aggregate.rs:+1:9: +1:10
+      let mut _2: u8;                      // in scope 0 at $DIR/aggregate.rs:+1:13: +1:24
+      let mut _3: (i32, u8, i32);          // in scope 0 at $DIR/aggregate.rs:+1:13: +1:22
+      let _4: ();                          // in scope 0 at $DIR/aggregate.rs:+2:5: +2:11
+      let mut _5: u8;                      // in scope 0 at $DIR/aggregate.rs:+2:9: +2:10
       scope 1 {
           debug x => _1;                   // in scope 1 at $DIR/aggregate.rs:+1:9: +1:10
       }
@@ -14,19 +16,29 @@
           StorageLive(_1);                 // scope 0 at $DIR/aggregate.rs:+1:9: +1:10
           StorageLive(_2);                 // scope 0 at $DIR/aggregate.rs:+1:13: +1:24
           StorageLive(_3);                 // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
-          Deinit(_3);                      // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
-          (_3.0: i32) = const 0_i32;       // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
-          (_3.1: i32) = const 1_i32;       // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
-          (_3.2: i32) = const 2_i32;       // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
--         _2 = (_3.1: i32);                // scope 0 at $DIR/aggregate.rs:+1:13: +1:24
--         _1 = Add(move _2, const 0_i32);  // scope 0 at $DIR/aggregate.rs:+1:13: +1:28
-+         _2 = const 1_i32;                // scope 0 at $DIR/aggregate.rs:+1:13: +1:24
-+         _1 = const 1_i32;                // scope 0 at $DIR/aggregate.rs:+1:13: +1:28
+          _3 = (const 0_i32, const 1_u8, const 2_i32); // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
+-         _2 = (_3.1: u8);                 // scope 0 at $DIR/aggregate.rs:+1:13: +1:24
+-         _1 = Add(move _2, const 0_u8);   // scope 0 at $DIR/aggregate.rs:+1:13: +1:28
++         _2 = const 1_u8;                 // scope 0 at $DIR/aggregate.rs:+1:13: +1:24
++         _1 = const 1_u8;                 // scope 0 at $DIR/aggregate.rs:+1:13: +1:28
           StorageDead(_2);                 // scope 0 at $DIR/aggregate.rs:+1:27: +1:28
           StorageDead(_3);                 // scope 0 at $DIR/aggregate.rs:+1:28: +1:29
-          _0 = const ();                   // scope 0 at $DIR/aggregate.rs:+0:11: +2:2
-          StorageDead(_1);                 // scope 0 at $DIR/aggregate.rs:+2:1: +2:2
-          return;                          // scope 0 at $DIR/aggregate.rs:+2:2: +2:2
+          StorageLive(_4);                 // scope 1 at $DIR/aggregate.rs:+2:5: +2:11
+          StorageLive(_5);                 // scope 1 at $DIR/aggregate.rs:+2:9: +2:10
+-         _5 = _1;                         // scope 1 at $DIR/aggregate.rs:+2:9: +2:10
++         _5 = const 1_u8;                 // scope 1 at $DIR/aggregate.rs:+2:9: +2:10
+          _4 = foo(move _5) -> bb1;        // scope 1 at $DIR/aggregate.rs:+2:5: +2:11
+                                           // mir::Constant
+                                           // + span: $DIR/aggregate.rs:8:5: 8:8
+                                           // + literal: Const { ty: fn(u8) {foo}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_5);                 // scope 1 at $DIR/aggregate.rs:+2:10: +2:11
+          StorageDead(_4);                 // scope 1 at $DIR/aggregate.rs:+2:11: +2:12
+          _0 = const ();                   // scope 0 at $DIR/aggregate.rs:+0:11: +3:2
+          StorageDead(_1);                 // scope 0 at $DIR/aggregate.rs:+3:1: +3:2
+          return;                          // scope 0 at $DIR/aggregate.rs:+3:2: +3:2
       }
   }
   
diff --git a/tests/mir-opt/const_prop/aggregate.main.PreCodegen.after.mir b/tests/mir-opt/const_prop/aggregate.main.PreCodegen.after.mir
index cfc9a72e3..4706af92c 100644
--- a/tests/mir-opt/const_prop/aggregate.main.PreCodegen.after.mir
+++ b/tests/mir-opt/const_prop/aggregate.main.PreCodegen.after.mir
@@ -2,9 +2,11 @@
 
 fn main() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/aggregate.rs:+0:11: +0:11
-    let _1: i32;                         // in scope 0 at $DIR/aggregate.rs:+1:9: +1:10
-    let mut _2: i32;                     // in scope 0 at $DIR/aggregate.rs:+1:13: +1:24
-    let mut _3: (i32, i32, i32);         // in scope 0 at $DIR/aggregate.rs:+1:13: +1:22
+    let _1: u8;                          // in scope 0 at $DIR/aggregate.rs:+1:9: +1:10
+    let mut _2: u8;                      // in scope 0 at $DIR/aggregate.rs:+1:13: +1:24
+    let mut _3: (i32, u8, i32);          // in scope 0 at $DIR/aggregate.rs:+1:13: +1:22
+    let _4: ();                          // in scope 0 at $DIR/aggregate.rs:+2:5: +2:11
+    let mut _5: u8;                      // in scope 0 at $DIR/aggregate.rs:+2:9: +2:10
     scope 1 {
         debug x => _1;                   // in scope 1 at $DIR/aggregate.rs:+1:9: +1:10
     }
@@ -13,16 +15,25 @@ fn main() -> () {
         StorageLive(_1);                 // scope 0 at $DIR/aggregate.rs:+1:9: +1:10
         StorageLive(_2);                 // scope 0 at $DIR/aggregate.rs:+1:13: +1:24
         StorageLive(_3);                 // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
-        Deinit(_3);                      // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
-        (_3.0: i32) = const 0_i32;       // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
-        (_3.1: i32) = const 1_i32;       // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
-        (_3.2: i32) = const 2_i32;       // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
-        _2 = const 1_i32;                // scope 0 at $DIR/aggregate.rs:+1:13: +1:24
-        _1 = const 1_i32;                // scope 0 at $DIR/aggregate.rs:+1:13: +1:28
+        _3 = (const 0_i32, const 1_u8, const 2_i32); // scope 0 at $DIR/aggregate.rs:+1:13: +1:22
+        _2 = const 1_u8;                 // scope 0 at $DIR/aggregate.rs:+1:13: +1:24
+        _1 = const 1_u8;                 // scope 0 at $DIR/aggregate.rs:+1:13: +1:28
         StorageDead(_2);                 // scope 0 at $DIR/aggregate.rs:+1:27: +1:28
         StorageDead(_3);                 // scope 0 at $DIR/aggregate.rs:+1:28: +1:29
-        _0 = const ();                   // scope 0 at $DIR/aggregate.rs:+0:11: +2:2
-        StorageDead(_1);                 // scope 0 at $DIR/aggregate.rs:+2:1: +2:2
-        return;                          // scope 0 at $DIR/aggregate.rs:+2:2: +2:2
+        StorageLive(_4);                 // scope 1 at $DIR/aggregate.rs:+2:5: +2:11
+        StorageLive(_5);                 // scope 1 at $DIR/aggregate.rs:+2:9: +2:10
+        _5 = const 1_u8;                 // scope 1 at $DIR/aggregate.rs:+2:9: +2:10
+        _4 = foo(move _5) -> bb1;        // scope 1 at $DIR/aggregate.rs:+2:5: +2:11
+                                         // mir::Constant
+                                         // + span: $DIR/aggregate.rs:8:5: 8:8
+                                         // + literal: Const { ty: fn(u8) {foo}, val: Value(<ZST>) }
+    }
+
+    bb1: {
+        StorageDead(_5);                 // scope 1 at $DIR/aggregate.rs:+2:10: +2:11
+        StorageDead(_4);                 // scope 1 at $DIR/aggregate.rs:+2:11: +2:12
+        _0 = const ();                   // scope 0 at $DIR/aggregate.rs:+0:11: +3:2
+        StorageDead(_1);                 // scope 0 at $DIR/aggregate.rs:+3:1: +3:2
+        return;                          // scope 0 at $DIR/aggregate.rs:+3:2: +3:2
     }
 }
diff --git a/tests/mir-opt/const_prop/aggregate.rs b/tests/mir-opt/const_prop/aggregate.rs
index 6a3080384..aa123b7a8 100644
--- a/tests/mir-opt/const_prop/aggregate.rs
+++ b/tests/mir-opt/const_prop/aggregate.rs
@@ -5,4 +5,13 @@
 // EMIT_MIR aggregate.main.PreCodegen.after.mir
 fn main() {
     let x = (0, 1, 2).1 + 0;
+    foo(x);
+}
+
+// EMIT_MIR aggregate.foo.ConstProp.diff
+// EMIT_MIR aggregate.foo.PreCodegen.after.mir
+fn foo(x: u8) {
+    // Verify that we still propagate if part of the aggregate is not known.
+    let first = (0, x).0 + 1;
+    let second = (x, 1).1 + 2;
 }
diff --git a/tests/mir-opt/const_prop/bad_op_div_by_zero.main.ConstProp.diff b/tests/mir-opt/const_prop/bad_op_div_by_zero.main.ConstProp.diff
index bea32a67e..900061a48 100644
--- a/tests/mir-opt/const_prop/bad_op_div_by_zero.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/bad_op_div_by_zero.main.ConstProp.diff
@@ -24,9 +24,10 @@
           StorageLive(_3);                 // scope 1 at $DIR/bad_op_div_by_zero.rs:+2:18: +2:19
 -         _3 = _1;                         // scope 1 at $DIR/bad_op_div_by_zero.rs:+2:18: +2:19
 -         _4 = Eq(_3, const 0_i32);        // scope 1 at $DIR/bad_op_div_by_zero.rs:+2:14: +2:19
+-         assert(!move _4, "attempt to divide `{}` by zero", const 1_i32) -> bb1; // scope 1 at $DIR/bad_op_div_by_zero.rs:+2:14: +2:19
 +         _3 = const 0_i32;                // scope 1 at $DIR/bad_op_div_by_zero.rs:+2:18: +2:19
 +         _4 = const true;                 // scope 1 at $DIR/bad_op_div_by_zero.rs:+2:14: +2:19
-          assert(!move _4, "attempt to divide `{}` by zero", const 1_i32) -> bb1; // scope 1 at $DIR/bad_op_div_by_zero.rs:+2:14: +2:19
++         assert(!const true, "attempt to divide `{}` by zero", const 1_i32) -> bb1; // scope 1 at $DIR/bad_op_div_by_zero.rs:+2:14: +2:19
       }
   
       bb1: {
diff --git a/tests/mir-opt/const_prop/bad_op_mod_by_zero.main.ConstProp.diff b/tests/mir-opt/const_prop/bad_op_mod_by_zero.main.ConstProp.diff
index 8485703e3..ae9ffd519 100644
--- a/tests/mir-opt/const_prop/bad_op_mod_by_zero.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/bad_op_mod_by_zero.main.ConstProp.diff
@@ -18,35 +18,27 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/bad_op_mod_by_zero.rs:+1:9: +1:10
           _1 = const 0_i32;                // scope 0 at $DIR/bad_op_mod_by_zero.rs:+1:13: +1:14
           StorageLive(_2);                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:9: +2:11
-          StorageLive(_3);                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:18: +2:19
--         _3 = _1;                         // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:18: +2:19
--         _4 = Eq(_3, const 0_i32);        // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
+-         _4 = Eq(_1, const 0_i32);        // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 -         assert(!move _4, "attempt to calculate the remainder of `{}` with a divisor of zero", const 1_i32) -> bb1; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
-+         _3 = const 0_i32;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:18: +2:19
 +         _4 = const true;                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 +         assert(!const true, "attempt to calculate the remainder of `{}` with a divisor of zero", const 1_i32) -> bb1; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
       }
   
       bb1: {
--         _5 = Eq(_3, const -1_i32);       // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
+          _5 = Eq(_1, const -1_i32);       // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 -         _6 = Eq(const 1_i32, const i32::MIN); // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 -         _7 = BitAnd(move _5, move _6);   // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
--         assert(!move _7, "attempt to compute the remainder of `{} % {}`, which would overflow", const 1_i32, _3) -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
-+         _5 = const false;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
+-         assert(!move _7, "attempt to compute the remainder of `{} % {}`, which would overflow", const 1_i32, _1) -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 +         _6 = const false;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
 +         _7 = const false;                // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
-+         assert(!const false, "attempt to compute the remainder of `{} % {}`, which would overflow", const 1_i32, const 0_i32) -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
++         assert(!const false, "attempt to compute the remainder of `{} % {}`, which would overflow", const 1_i32, _1) -> bb2; // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
       }
   
       bb2: {
--         _2 = Rem(const 1_i32, move _3);  // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
-+         _2 = Rem(const 1_i32, const 0_i32); // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
-          StorageDead(_3);                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:18: +2:19
+          _2 = Rem(const 1_i32, _1);       // scope 1 at $DIR/bad_op_mod_by_zero.rs:+2:14: +2:19
           StorageDead(_2);                 // scope 1 at $DIR/bad_op_mod_by_zero.rs:+3:1: +3:2
-          StorageDead(_1);                 // scope 0 at $DIR/bad_op_mod_by_zero.rs:+3:1: +3:2
           return;                          // scope 0 at $DIR/bad_op_mod_by_zero.rs:+3:2: +3:2
       }
   }
diff --git a/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.32bit.diff b/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.32bit.diff
index 27e41d486..38d402b8f 100644
--- a/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.32bit.diff
+++ b/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.32bit.diff
@@ -23,24 +23,21 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:9: +1:10
           StorageLive(_2);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
-          StorageLive(_3);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           _8 = const _;                    // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
                                            // mir::Constant
                                            // + span: $DIR/bad_op_unsafe_oob_for_slices.rs:5:25: 5:35
                                            // + literal: Const { ty: &[i32; 3], val: Unevaluated(main, [], Some(promoted[0])) }
-          _3 = _8;                         // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
-          _2 = &raw const (*_3);           // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
+          _2 = &raw const (*_8);           // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           _1 = move _2 as *const [i32] (Pointer(Unsize)); // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           StorageDead(_2);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:34: +1:35
-          StorageDead(_3);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:35: +1:36
           StorageLive(_4);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:13: +3:15
           StorageLive(_5);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:23: +3:24
           _5 = const 3_usize;              // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:23: +3:24
-          _6 = Len((*_1));                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
+          _6 = const 3_usize;              // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
 -         _7 = Lt(_5, _6);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
 -         assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _5) -> bb1; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
-+         _7 = Lt(const 3_usize, _6);      // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
-+         assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, const 3_usize) -> bb1; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
++         _7 = const false;                // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
++         assert(const false, "index out of bounds: the length is {} but the index is {}", const 3_usize, const 3_usize) -> bb1; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
       }
   
       bb1: {
diff --git a/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff b/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff
index 27e41d486..38d402b8f 100644
--- a/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff
+++ b/tests/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff
@@ -23,24 +23,21 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:9: +1:10
           StorageLive(_2);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
-          StorageLive(_3);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           _8 = const _;                    // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
                                            // mir::Constant
                                            // + span: $DIR/bad_op_unsafe_oob_for_slices.rs:5:25: 5:35
                                            // + literal: Const { ty: &[i32; 3], val: Unevaluated(main, [], Some(promoted[0])) }
-          _3 = _8;                         // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
-          _2 = &raw const (*_3);           // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
+          _2 = &raw const (*_8);           // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           _1 = move _2 as *const [i32] (Pointer(Unsize)); // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:25: +1:35
           StorageDead(_2);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:34: +1:35
-          StorageDead(_3);                 // scope 0 at $DIR/bad_op_unsafe_oob_for_slices.rs:+1:35: +1:36
           StorageLive(_4);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:13: +3:15
           StorageLive(_5);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:23: +3:24
           _5 = const 3_usize;              // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:23: +3:24
-          _6 = Len((*_1));                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
+          _6 = const 3_usize;              // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
 -         _7 = Lt(_5, _6);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
 -         assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _5) -> bb1; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
-+         _7 = Lt(const 3_usize, _6);      // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
-+         assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, const 3_usize) -> bb1; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
++         _7 = const false;                // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
++         assert(const false, "index out of bounds: the length is {} but the index is {}", const 3_usize, const 3_usize) -> bb1; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:+3:18: +3:25
       }
   
       bb1: {
diff --git a/tests/mir-opt/const_prop/boolean_identities.test.ConstProp.diff b/tests/mir-opt/const_prop/boolean_identities.test.ConstProp.diff
index 0de800917..549b4711e 100644
--- a/tests/mir-opt/const_prop/boolean_identities.test.ConstProp.diff
+++ b/tests/mir-opt/const_prop/boolean_identities.test.ConstProp.diff
@@ -12,18 +12,12 @@
   
       bb0: {
           StorageLive(_3);                 // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:15
-          StorageLive(_4);                 // scope 0 at $DIR/boolean_identities.rs:+1:6: +1:7
-          _4 = _2;                         // scope 0 at $DIR/boolean_identities.rs:+1:6: +1:7
--         _3 = BitOr(move _4, const true); // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:15
+-         _3 = BitOr(_2, const true);      // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:15
 +         _3 = const true;                 // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:15
-          StorageDead(_4);                 // scope 0 at $DIR/boolean_identities.rs:+1:14: +1:15
           StorageLive(_5);                 // scope 0 at $DIR/boolean_identities.rs:+1:18: +1:29
-          StorageLive(_6);                 // scope 0 at $DIR/boolean_identities.rs:+1:19: +1:20
-          _6 = _1;                         // scope 0 at $DIR/boolean_identities.rs:+1:19: +1:20
--         _5 = BitAnd(move _6, const false); // scope 0 at $DIR/boolean_identities.rs:+1:18: +1:29
-+         _5 = const false;                // scope 0 at $DIR/boolean_identities.rs:+1:18: +1:29
-          StorageDead(_6);                 // scope 0 at $DIR/boolean_identities.rs:+1:28: +1:29
+-         _5 = BitAnd(_1, const false);    // scope 0 at $DIR/boolean_identities.rs:+1:18: +1:29
 -         _0 = BitAnd(move _3, move _5);   // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:29
++         _5 = const false;                // scope 0 at $DIR/boolean_identities.rs:+1:18: +1:29
 +         _0 = const false;                // scope 0 at $DIR/boolean_identities.rs:+1:5: +1:29
           StorageDead(_5);                 // scope 0 at $DIR/boolean_identities.rs:+1:28: +1:29
           StorageDead(_3);                 // scope 0 at $DIR/boolean_identities.rs:+1:28: +1:29
diff --git a/tests/mir-opt/const_prop/discriminant.main.ConstProp.32bit.diff b/tests/mir-opt/const_prop/discriminant.main.ConstProp.32bit.diff
index b4dccecc6..b9a10704b 100644
--- a/tests/mir-opt/const_prop/discriminant.main.ConstProp.32bit.diff
+++ b/tests/mir-opt/const_prop/discriminant.main.ConstProp.32bit.diff
@@ -17,17 +17,20 @@
           StorageLive(_1);                 // scope 0 at $DIR/discriminant.rs:+1:9: +1:10
           StorageLive(_2);                 // scope 0 at $DIR/discriminant.rs:+1:13: +1:64
           StorageLive(_3);                 // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
-          Deinit(_3);                      // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
-          ((_3 as Some).0: bool) = const true; // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
-          discriminant(_3) = 1;            // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
+-         _3 = Option::<bool>::Some(const true); // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
 -         _4 = discriminant(_3);           // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
 -         switchInt(move _4) -> [1: bb1, otherwise: bb3]; // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
++         _3 = const Option::<bool>::Some(true); // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
++                                          // mir::Constant
++                                          // + span: $DIR/discriminant.rs:12:34: 12:44
++                                          // + literal: Const { ty: Option<bool>, val: Value(Scalar(0x01)) }
 +         _4 = const 1_isize;              // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
 +         switchInt(const 1_isize) -> [1: bb1, otherwise: bb3]; // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
       }
   
       bb1: {
-          switchInt(((_3 as Some).0: bool)) -> [0: bb3, otherwise: bb2]; // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
+-         switchInt(((_3 as Some).0: bool)) -> [0: bb3, otherwise: bb2]; // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
++         switchInt(const true) -> [0: bb3, otherwise: bb2]; // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
       }
   
       bb2: {
diff --git a/tests/mir-opt/const_prop/discriminant.main.ConstProp.64bit.diff b/tests/mir-opt/const_prop/discriminant.main.ConstProp.64bit.diff
index b4dccecc6..b9a10704b 100644
--- a/tests/mir-opt/const_prop/discriminant.main.ConstProp.64bit.diff
+++ b/tests/mir-opt/const_prop/discriminant.main.ConstProp.64bit.diff
@@ -17,17 +17,20 @@
           StorageLive(_1);                 // scope 0 at $DIR/discriminant.rs:+1:9: +1:10
           StorageLive(_2);                 // scope 0 at $DIR/discriminant.rs:+1:13: +1:64
           StorageLive(_3);                 // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
-          Deinit(_3);                      // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
-          ((_3 as Some).0: bool) = const true; // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
-          discriminant(_3) = 1;            // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
+-         _3 = Option::<bool>::Some(const true); // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
 -         _4 = discriminant(_3);           // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
 -         switchInt(move _4) -> [1: bb1, otherwise: bb3]; // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
++         _3 = const Option::<bool>::Some(true); // scope 2 at $DIR/discriminant.rs:+1:34: +1:44
++                                          // mir::Constant
++                                          // + span: $DIR/discriminant.rs:12:34: 12:44
++                                          // + literal: Const { ty: Option<bool>, val: Value(Scalar(0x01)) }
 +         _4 = const 1_isize;              // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
 +         switchInt(const 1_isize) -> [1: bb1, otherwise: bb3]; // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
       }
   
       bb1: {
-          switchInt(((_3 as Some).0: bool)) -> [0: bb3, otherwise: bb2]; // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
+-         switchInt(((_3 as Some).0: bool)) -> [0: bb3, otherwise: bb2]; // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
++         switchInt(const true) -> [0: bb3, otherwise: bb2]; // scope 2 at $DIR/discriminant.rs:+1:21: +1:31
       }
   
       bb2: {
diff --git a/tests/mir-opt/const_prop/inherit_overflow.main.ConstProp.diff b/tests/mir-opt/const_prop/inherit_overflow.main.ConstProp.diff
new file mode 100644
index 000000000..d03c23a3f
--- /dev/null
+++ b/tests/mir-opt/const_prop/inherit_overflow.main.ConstProp.diff
@@ -0,0 +1,39 @@
+- // MIR for `main` before ConstProp
++ // MIR for `main` after ConstProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/inherit_overflow.rs:+0:11: +0:11
+      let mut _1: u8;                      // in scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+      let mut _2: u8;                      // in scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+      let mut _3: u8;                      // in scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+      scope 1 {
+      }
+      scope 2 (inlined <u8 as Add>::add) { // at $DIR/inherit_overflow.rs:8:13: 8:47
+          debug self => _2;                // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          debug other => _3;               // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          let mut _4: (u8, bool);          // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageLive(_2);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          _2 = const u8::MAX;              // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageLive(_3);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          _3 = const 1_u8;                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+-         _4 = CheckedAdd(_2, _3);         // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+-         assert(!move (_4.1: bool), "attempt to compute `{} + {}`, which would overflow", _2, _3) -> bb1; // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
++         _4 = const (0_u8, true);         // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
++         assert(!const true, "attempt to compute `{} + {}`, which would overflow", _2, _3) -> bb1; // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+      }
+  
+      bb1: {
+-         _1 = move (_4.0: u8);            // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
++         _1 = const 0_u8;                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          StorageDead(_3);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageDead(_2);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageDead(_1);                 // scope 0 at $DIR/inherit_overflow.rs:+3:47: +3:48
+          _0 = const ();                   // scope 0 at $DIR/inherit_overflow.rs:+0:11: +4:2
+          return;                          // scope 0 at $DIR/inherit_overflow.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/const_prop/inherit_overflow.rs b/tests/mir-opt/const_prop/inherit_overflow.rs
new file mode 100644
index 000000000..541a8c5c3
--- /dev/null
+++ b/tests/mir-opt/const_prop/inherit_overflow.rs
@@ -0,0 +1,9 @@
+// unit-test: ConstProp
+// compile-flags: -Zmir-enable-passes=+Inline
+
+// EMIT_MIR inherit_overflow.main.ConstProp.diff
+fn main() {
+    // After inlining, this will contain a `CheckedBinaryOp`.
+    // Propagating the overflow is ok as codegen will just skip emitting the panic.
+    let _ = <u8 as std::ops::Add>::add(255, 1);
+}
diff --git a/tests/mir-opt/const_prop/invalid_constant.main.ConstProp.diff b/tests/mir-opt/const_prop/invalid_constant.main.ConstProp.diff
index 6c4757c1a..4f056dd85 100644
--- a/tests/mir-opt/const_prop/invalid_constant.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/invalid_constant.main.ConstProp.diff
@@ -32,16 +32,14 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/invalid_constant.rs:+6:9: +6:22
           StorageLive(_2);                 // scope 2 at $DIR/invalid_constant.rs:+6:34: +6:63
-          Deinit(_2);                      // scope 2 at $DIR/invalid_constant.rs:+6:34: +6:63
-          (_2.0: u32) = const 1114113_u32; // scope 2 at $DIR/invalid_constant.rs:+6:34: +6:63
+          _2 = InvalidChar { int: const 1114113_u32 }; // scope 2 at $DIR/invalid_constant.rs:+6:34: +6:63
 -         _1 = (_2.1: char);               // scope 2 at $DIR/invalid_constant.rs:+6:34: +6:67
 +         _1 = const {transmute(0x00110001): char}; // scope 2 at $DIR/invalid_constant.rs:+6:34: +6:67
           StorageDead(_2);                 // scope 0 at $DIR/invalid_constant.rs:+6:69: +6:70
           StorageLive(_3);                 // scope 1 at $DIR/invalid_constant.rs:+13:9: +13:21
           StorageLive(_4);                 // scope 1 at $DIR/invalid_constant.rs:+13:25: +13:59
           StorageLive(_5);                 // scope 4 at $DIR/invalid_constant.rs:+13:34: +13:55
-          Deinit(_5);                      // scope 4 at $DIR/invalid_constant.rs:+13:34: +13:55
-          (_5.0: u32) = const 4_u32;       // scope 4 at $DIR/invalid_constant.rs:+13:34: +13:55
+          _5 = InvalidTag { int: const 4_u32 }; // scope 4 at $DIR/invalid_constant.rs:+13:34: +13:55
 -         _4 = (_5.1: E);                  // scope 4 at $DIR/invalid_constant.rs:+13:34: +13:57
 -         _3 = [move _4];                  // scope 1 at $DIR/invalid_constant.rs:+13:24: +13:60
 +         _4 = const Scalar(0x00000004): E; // scope 4 at $DIR/invalid_constant.rs:+13:34: +13:57
diff --git a/tests/mir-opt/const_prop/issue_66971.main.ConstProp.diff b/tests/mir-opt/const_prop/issue_66971.main.ConstProp.diff
index 488e772d0..964dd3080 100644
--- a/tests/mir-opt/const_prop/issue_66971.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/issue_66971.main.ConstProp.diff
@@ -5,13 +5,14 @@
       let mut _0: ();                      // return place in scope 0 at $DIR/issue_66971.rs:+0:11: +0:11
       let _1: ();                          // in scope 0 at $DIR/issue_66971.rs:+1:5: +1:23
       let mut _2: ((), u8, u8);            // in scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
+      let mut _3: ();                      // in scope 0 at $DIR/issue_66971.rs:+1:13: +1:15
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/issue_66971.rs:+1:5: +1:23
           StorageLive(_2);                 // scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
-          Deinit(_2);                      // scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
-          (_2.1: u8) = const 0_u8;         // scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
-          (_2.2: u8) = const 0_u8;         // scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
+          StorageLive(_3);                 // scope 0 at $DIR/issue_66971.rs:+1:13: +1:15
+          _2 = (move _3, const 0_u8, const 0_u8); // scope 0 at $DIR/issue_66971.rs:+1:12: +1:22
+          StorageDead(_3);                 // scope 0 at $DIR/issue_66971.rs:+1:21: +1:22
           _1 = encode(move _2) -> bb1;     // scope 0 at $DIR/issue_66971.rs:+1:5: +1:23
                                            // mir::Constant
                                            // + span: $DIR/issue_66971.rs:17:5: 17:11
diff --git a/tests/mir-opt/const_prop/issue_67019.main.ConstProp.diff b/tests/mir-opt/const_prop/issue_67019.main.ConstProp.diff
index cd5304859..a631cb310 100644
--- a/tests/mir-opt/const_prop/issue_67019.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/issue_67019.main.ConstProp.diff
@@ -11,12 +11,9 @@
           StorageLive(_1);                 // scope 0 at $DIR/issue_67019.rs:+1:5: +1:20
           StorageLive(_2);                 // scope 0 at $DIR/issue_67019.rs:+1:10: +1:19
           StorageLive(_3);                 // scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
-          Deinit(_3);                      // scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
-          (_3.0: u8) = const 1_u8;         // scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
-          (_3.1: u8) = const 2_u8;         // scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
-          Deinit(_2);                      // scope 0 at $DIR/issue_67019.rs:+1:10: +1:19
--         (_2.0: (u8, u8)) = move _3;      // scope 0 at $DIR/issue_67019.rs:+1:10: +1:19
-+         (_2.0: (u8, u8)) = const (1_u8, 2_u8); // scope 0 at $DIR/issue_67019.rs:+1:10: +1:19
+-         _3 = (const 1_u8, const 2_u8);   // scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
++         _3 = const (1_u8, 2_u8);         // scope 0 at $DIR/issue_67019.rs:+1:11: +1:17
+          _2 = (move _3,);                 // scope 0 at $DIR/issue_67019.rs:+1:10: +1:19
           StorageDead(_3);                 // scope 0 at $DIR/issue_67019.rs:+1:18: +1:19
           _1 = test(move _2) -> bb1;       // scope 0 at $DIR/issue_67019.rs:+1:5: +1:20
                                            // mir::Constant
diff --git a/tests/mir-opt/const_prop/mult_by_zero.test.ConstProp.diff b/tests/mir-opt/const_prop/mult_by_zero.test.ConstProp.diff
index 629c8e601..1cfe47d0a 100644
--- a/tests/mir-opt/const_prop/mult_by_zero.test.ConstProp.diff
+++ b/tests/mir-opt/const_prop/mult_by_zero.test.ConstProp.diff
@@ -7,11 +7,8 @@
       let mut _2: i32;                     // in scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:4
   
       bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:4
-          _2 = _1;                         // scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:4
--         _0 = Mul(move _2, const 0_i32);  // scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:8
+-         _0 = Mul(_1, const 0_i32);       // scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:8
 +         _0 = const 0_i32;                // scope 0 at $DIR/mult_by_zero.rs:+1:3: +1:8
-          StorageDead(_2);                 // scope 0 at $DIR/mult_by_zero.rs:+1:7: +1:8
           return;                          // scope 0 at $DIR/mult_by_zero.rs:+2:2: +2:2
       }
   }
diff --git a/tests/mir-opt/const_prop/mutable_variable_aggregate.main.ConstProp.diff b/tests/mir-opt/const_prop/mutable_variable_aggregate.main.ConstProp.diff
index f6bf52206..d088c4f66 100644
--- a/tests/mir-opt/const_prop/mutable_variable_aggregate.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/mutable_variable_aggregate.main.ConstProp.diff
@@ -3,26 +3,27 @@
   
   fn main() -> () {
       let mut _0: ();                      // return place in scope 0 at $DIR/mutable_variable_aggregate.rs:+0:11: +0:11
-      let mut _1: (i32, i32);              // in scope 0 at $DIR/mutable_variable_aggregate.rs:+1:9: +1:14
+      let mut _3: i32;                     // in scope 0 at $DIR/mutable_variable_aggregate.rs:+1:9: +1:14
+      let mut _4: i32;                     // in scope 0 at $DIR/mutable_variable_aggregate.rs:+1:9: +1:14
       scope 1 {
-          debug x => _1;                   // in scope 1 at $DIR/mutable_variable_aggregate.rs:+1:9: +1:14
-          let _2: (i32, i32);              // in scope 1 at $DIR/mutable_variable_aggregate.rs:+3:9: +3:10
+          debug x => (i32, i32){ .0 => _3, .1 => _4, }; // in scope 1 at $DIR/mutable_variable_aggregate.rs:+1:9: +1:14
+          let _1: i32;                     // in scope 1 at $DIR/mutable_variable_aggregate.rs:+3:9: +3:10
+          let _2: i32;                     // in scope 1 at $DIR/mutable_variable_aggregate.rs:+3:9: +3:10
           scope 2 {
-              debug y => _2;               // in scope 2 at $DIR/mutable_variable_aggregate.rs:+3:9: +3:10
+              debug y => (i32, i32){ .0 => _3, .1 => _2, }; // in scope 2 at $DIR/mutable_variable_aggregate.rs:+3:9: +3:10
           }
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/mutable_variable_aggregate.rs:+1:9: +1:14
-          Deinit(_1);                      // scope 0 at $DIR/mutable_variable_aggregate.rs:+1:17: +1:25
-          (_1.0: i32) = const 42_i32;      // scope 0 at $DIR/mutable_variable_aggregate.rs:+1:17: +1:25
-          (_1.1: i32) = const 43_i32;      // scope 0 at $DIR/mutable_variable_aggregate.rs:+1:17: +1:25
-          (_1.1: i32) = const 99_i32;      // scope 1 at $DIR/mutable_variable_aggregate.rs:+2:5: +2:13
+          StorageLive(_4);                 // scope 0 at $DIR/mutable_variable_aggregate.rs:+1:9: +1:14
+          _3 = const 42_i32;               // scope 0 at $DIR/mutable_variable_aggregate.rs:+1:17: +1:25
+          _4 = const 43_i32;               // scope 0 at $DIR/mutable_variable_aggregate.rs:+1:17: +1:25
+          _4 = const 99_i32;               // scope 1 at $DIR/mutable_variable_aggregate.rs:+2:5: +2:13
           StorageLive(_2);                 // scope 1 at $DIR/mutable_variable_aggregate.rs:+3:9: +3:10
--         _2 = _1;                         // scope 1 at $DIR/mutable_variable_aggregate.rs:+3:13: +3:14
-+         _2 = const (42_i32, 99_i32);     // scope 1 at $DIR/mutable_variable_aggregate.rs:+3:13: +3:14
+-         _2 = _4;                         // scope 1 at $DIR/mutable_variable_aggregate.rs:+3:13: +3:14
++         _2 = const 99_i32;               // scope 1 at $DIR/mutable_variable_aggregate.rs:+3:13: +3:14
           StorageDead(_2);                 // scope 1 at $DIR/mutable_variable_aggregate.rs:+4:1: +4:2
-          StorageDead(_1);                 // scope 0 at $DIR/mutable_variable_aggregate.rs:+4:1: +4:2
+          StorageDead(_4);                 // scope 0 at $DIR/mutable_variable_aggregate.rs:+4:1: +4:2
           return;                          // scope 0 at $DIR/mutable_variable_aggregate.rs:+4:2: +4:2
       }
   }
diff --git a/tests/mir-opt/const_prop/mutable_variable_aggregate_mut_ref.main.ConstProp.diff b/tests/mir-opt/const_prop/mutable_variable_aggregate_mut_ref.main.ConstProp.diff
index 213a70227..134f0c080 100644
--- a/tests/mir-opt/const_prop/mutable_variable_aggregate_mut_ref.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/mutable_variable_aggregate_mut_ref.main.ConstProp.diff
@@ -9,24 +9,26 @@
           let _2: &mut (i32, i32);         // in scope 1 at $DIR/mutable_variable_aggregate_mut_ref.rs:+2:9: +2:10
           scope 2 {
               debug z => _2;               // in scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+2:9: +2:10
-              let _3: (i32, i32);          // in scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+4:9: +4:10
+              let _3: i32;                 // in scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+4:9: +4:10
+              let _4: i32;                 // in scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+4:9: +4:10
               scope 3 {
-                  debug y => _3;           // in scope 3 at $DIR/mutable_variable_aggregate_mut_ref.rs:+4:9: +4:10
+                  debug y => (i32, i32){ .0 => _3, .1 => _4, }; // in scope 3 at $DIR/mutable_variable_aggregate_mut_ref.rs:+4:9: +4:10
               }
           }
       }
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/mutable_variable_aggregate_mut_ref.rs:+1:9: +1:14
-          Deinit(_1);                      // scope 0 at $DIR/mutable_variable_aggregate_mut_ref.rs:+1:17: +1:25
-          (_1.0: i32) = const 42_i32;      // scope 0 at $DIR/mutable_variable_aggregate_mut_ref.rs:+1:17: +1:25
-          (_1.1: i32) = const 43_i32;      // scope 0 at $DIR/mutable_variable_aggregate_mut_ref.rs:+1:17: +1:25
+          _1 = (const 42_i32, const 43_i32); // scope 0 at $DIR/mutable_variable_aggregate_mut_ref.rs:+1:17: +1:25
           StorageLive(_2);                 // scope 1 at $DIR/mutable_variable_aggregate_mut_ref.rs:+2:9: +2:10
           _2 = &mut _1;                    // scope 1 at $DIR/mutable_variable_aggregate_mut_ref.rs:+2:13: +2:19
           ((*_2).1: i32) = const 99_i32;   // scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+3:5: +3:13
           StorageLive(_3);                 // scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+4:9: +4:10
-          _3 = _1;                         // scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+4:13: +4:14
+          StorageLive(_4);                 // scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+4:9: +4:10
+          _3 = (_1.0: i32);                // scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+4:13: +4:14
+          _4 = (_1.1: i32);                // scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+4:13: +4:14
           StorageDead(_3);                 // scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+5:1: +5:2
+          StorageDead(_4);                 // scope 2 at $DIR/mutable_variable_aggregate_mut_ref.rs:+5:1: +5:2
           StorageDead(_2);                 // scope 1 at $DIR/mutable_variable_aggregate_mut_ref.rs:+5:1: +5:2
           StorageDead(_1);                 // scope 0 at $DIR/mutable_variable_aggregate_mut_ref.rs:+5:1: +5:2
           return;                          // scope 0 at $DIR/mutable_variable_aggregate_mut_ref.rs:+5:2: +5:2
diff --git a/tests/mir-opt/const_prop/mutable_variable_unprop_assign.main.ConstProp.diff b/tests/mir-opt/const_prop/mutable_variable_unprop_assign.main.ConstProp.diff
index c3f77b960..4010dd6c6 100644
--- a/tests/mir-opt/const_prop/mutable_variable_unprop_assign.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/mutable_variable_unprop_assign.main.ConstProp.diff
@@ -16,7 +16,7 @@
                   debug y => _3;           // in scope 3 at $DIR/mutable_variable_unprop_assign.rs:+4:9: +4:10
                   let _4: i32;             // in scope 3 at $DIR/mutable_variable_unprop_assign.rs:+5:9: +5:10
                   scope 4 {
-                      debug z => _4;       // in scope 4 at $DIR/mutable_variable_unprop_assign.rs:+5:9: +5:10
+                      debug z => _5;       // in scope 4 at $DIR/mutable_variable_unprop_assign.rs:+5:9: +5:10
                   }
               }
           }
@@ -31,10 +31,7 @@
       }
   
       bb1: {
-          StorageLive(_5);                 // scope 1 at $DIR/mutable_variable_unprop_assign.rs:+2:9: +2:14
           StorageLive(_6);                 // scope 1 at $DIR/mutable_variable_unprop_assign.rs:+2:9: +2:14
-          Deinit(_5);                      // scope 1 at $DIR/mutable_variable_unprop_assign.rs:+2:29: +2:35
-          Deinit(_6);                      // scope 1 at $DIR/mutable_variable_unprop_assign.rs:+2:29: +2:35
           _5 = const 1_i32;                // scope 1 at $DIR/mutable_variable_unprop_assign.rs:+2:29: +2:35
           _6 = const 2_i32;                // scope 1 at $DIR/mutable_variable_unprop_assign.rs:+2:29: +2:35
           StorageLive(_2);                 // scope 2 at $DIR/mutable_variable_unprop_assign.rs:+3:11: +3:12
@@ -43,12 +40,7 @@
           StorageDead(_2);                 // scope 2 at $DIR/mutable_variable_unprop_assign.rs:+3:11: +3:12
           StorageLive(_3);                 // scope 2 at $DIR/mutable_variable_unprop_assign.rs:+4:9: +4:10
           _3 = _6;                         // scope 2 at $DIR/mutable_variable_unprop_assign.rs:+4:13: +4:16
-          StorageLive(_4);                 // scope 3 at $DIR/mutable_variable_unprop_assign.rs:+5:9: +5:10
--         _4 = _5;                         // scope 3 at $DIR/mutable_variable_unprop_assign.rs:+5:13: +5:16
-+         _4 = const 1_i32;                // scope 3 at $DIR/mutable_variable_unprop_assign.rs:+5:13: +5:16
-          StorageDead(_4);                 // scope 3 at $DIR/mutable_variable_unprop_assign.rs:+6:1: +6:2
           StorageDead(_3);                 // scope 2 at $DIR/mutable_variable_unprop_assign.rs:+6:1: +6:2
-          StorageDead(_5);                 // scope 1 at $DIR/mutable_variable_unprop_assign.rs:+6:1: +6:2
           StorageDead(_6);                 // scope 1 at $DIR/mutable_variable_unprop_assign.rs:+6:1: +6:2
           StorageDead(_1);                 // scope 0 at $DIR/mutable_variable_unprop_assign.rs:+6:1: +6:2
           return;                          // scope 0 at $DIR/mutable_variable_unprop_assign.rs:+6:2: +6:2
diff --git a/tests/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.32bit.diff b/tests/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.32bit.diff
index 7c7aeac4c..691aa01a5 100644
--- a/tests/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.32bit.diff
+++ b/tests/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.32bit.diff
@@ -17,7 +17,7 @@
               debug y => _3;               // in scope 2 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
               let _8: u32;                 // in scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
               scope 3 {
-                  debug z => _8;           // in scope 3 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
+                  debug z => _9;           // in scope 3 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
               }
           }
       }
@@ -50,14 +50,7 @@
 +         _3 = const 3_i32;                // scope 1 at $DIR/optimizes_into_variable.rs:+2:13: +2:34
           StorageDead(_5);                 // scope 1 at $DIR/optimizes_into_variable.rs:+2:34: +2:35
           StorageDead(_4);                 // scope 1 at $DIR/optimizes_into_variable.rs:+2:34: +2:35
-          StorageLive(_8);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
-          StorageLive(_9);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
-          Deinit(_9);                      // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
           _9 = const 42_u32;               // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
--         _8 = _9;                         // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:38
-+         _8 = const 42_u32;               // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:38
-          StorageDead(_9);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:38: +3:39
-          StorageDead(_8);                 // scope 2 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
           StorageDead(_3);                 // scope 1 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
           StorageDead(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
           return;                          // scope 0 at $DIR/optimizes_into_variable.rs:+4:2: +4:2
diff --git a/tests/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.64bit.diff b/tests/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.64bit.diff
index 7c7aeac4c..691aa01a5 100644
--- a/tests/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.64bit.diff
+++ b/tests/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.64bit.diff
@@ -17,7 +17,7 @@
               debug y => _3;               // in scope 2 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
               let _8: u32;                 // in scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
               scope 3 {
-                  debug z => _8;           // in scope 3 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
+                  debug z => _9;           // in scope 3 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
               }
           }
       }
@@ -50,14 +50,7 @@
 +         _3 = const 3_i32;                // scope 1 at $DIR/optimizes_into_variable.rs:+2:13: +2:34
           StorageDead(_5);                 // scope 1 at $DIR/optimizes_into_variable.rs:+2:34: +2:35
           StorageDead(_4);                 // scope 1 at $DIR/optimizes_into_variable.rs:+2:34: +2:35
-          StorageLive(_8);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
-          StorageLive(_9);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
-          Deinit(_9);                      // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
           _9 = const 42_u32;               // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
--         _8 = _9;                         // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:38
-+         _8 = const 42_u32;               // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:38
-          StorageDead(_9);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:38: +3:39
-          StorageDead(_8);                 // scope 2 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
           StorageDead(_3);                 // scope 1 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
           StorageDead(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
           return;                          // scope 0 at $DIR/optimizes_into_variable.rs:+4:2: +4:2
diff --git a/tests/mir-opt/const_prop/optimizes_into_variable.main.PreCodegen.after.32bit.mir b/tests/mir-opt/const_prop/optimizes_into_variable.main.PreCodegen.after.32bit.mir
index 9db87cfc8..81cfd22db 100644
--- a/tests/mir-opt/const_prop/optimizes_into_variable.main.PreCodegen.after.32bit.mir
+++ b/tests/mir-opt/const_prop/optimizes_into_variable.main.PreCodegen.after.32bit.mir
@@ -3,12 +3,12 @@
 fn main() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/optimizes_into_variable.rs:+0:11: +0:11
     let _1: i32;                         // in scope 0 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
+    let mut _3: u32;                     // in scope 0 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
     scope 1 {
         debug x => _1;                   // in scope 1 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
         let _2: i32;                     // in scope 1 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
         scope 2 {
             debug y => _2;               // in scope 2 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
-            let _3: u32;                 // in scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
             scope 3 {
                 debug z => _3;           // in scope 3 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
             }
@@ -18,8 +18,6 @@ fn main() -> () {
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
         StorageLive(_2);                 // scope 1 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
-        StorageLive(_3);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
-        StorageDead(_3);                 // scope 2 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         StorageDead(_2);                 // scope 1 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         StorageDead(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         return;                          // scope 0 at $DIR/optimizes_into_variable.rs:+4:2: +4:2
diff --git a/tests/mir-opt/const_prop/optimizes_into_variable.main.PreCodegen.after.64bit.mir b/tests/mir-opt/const_prop/optimizes_into_variable.main.PreCodegen.after.64bit.mir
index 9db87cfc8..81cfd22db 100644
--- a/tests/mir-opt/const_prop/optimizes_into_variable.main.PreCodegen.after.64bit.mir
+++ b/tests/mir-opt/const_prop/optimizes_into_variable.main.PreCodegen.after.64bit.mir
@@ -3,12 +3,12 @@
 fn main() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/optimizes_into_variable.rs:+0:11: +0:11
     let _1: i32;                         // in scope 0 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
+    let mut _3: u32;                     // in scope 0 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
     scope 1 {
         debug x => _1;                   // in scope 1 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
         let _2: i32;                     // in scope 1 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
         scope 2 {
             debug y => _2;               // in scope 2 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
-            let _3: u32;                 // in scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
             scope 3 {
                 debug z => _3;           // in scope 3 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
             }
@@ -18,8 +18,6 @@ fn main() -> () {
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
         StorageLive(_2);                 // scope 1 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
-        StorageLive(_3);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
-        StorageDead(_3);                 // scope 2 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         StorageDead(_2);                 // scope 1 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         StorageDead(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         return;                          // scope 0 at $DIR/optimizes_into_variable.rs:+4:2: +4:2
diff --git a/tests/mir-opt/const_prop/optimizes_into_variable.main.ScalarReplacementOfAggregates.32bit.diff b/tests/mir-opt/const_prop/optimizes_into_variable.main.ScalarReplacementOfAggregates.32bit.diff
index 3f9f3b2ea..98cd020da 100644
--- a/tests/mir-opt/const_prop/optimizes_into_variable.main.ScalarReplacementOfAggregates.32bit.diff
+++ b/tests/mir-opt/const_prop/optimizes_into_variable.main.ScalarReplacementOfAggregates.32bit.diff
@@ -48,20 +48,19 @@
           StorageDead(_4);                 // scope 1 at $DIR/optimizes_into_variable.rs:+2:34: +2:35
           StorageLive(_8);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
 -         StorageLive(_9);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
--         Deinit(_9);                      // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
--         (_9.0: u32) = const 12_u32;      // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
--         (_9.1: u32) = const 42_u32;      // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
+-         _9 = Point { x: const 12_u32, y: const 42_u32 }; // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
 -         _8 = (_9.1: u32);                // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:38
 -         StorageDead(_9);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:38: +3:39
 +         StorageLive(_10);                // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
 +         StorageLive(_11);                // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
-+         Deinit(_10);                     // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
-+         Deinit(_11);                     // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
++         nop;                             // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
 +         _10 = const 12_u32;              // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
 +         _11 = const 42_u32;              // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
++         nop;                             // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
 +         _8 = _11;                        // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:38
 +         StorageDead(_10);                // scope 2 at $DIR/optimizes_into_variable.rs:+3:38: +3:39
 +         StorageDead(_11);                // scope 2 at $DIR/optimizes_into_variable.rs:+3:38: +3:39
++         nop;                             // scope 2 at $DIR/optimizes_into_variable.rs:+3:38: +3:39
           nop;                             // scope 0 at $DIR/optimizes_into_variable.rs:+0:11: +4:2
           StorageDead(_8);                 // scope 2 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
           StorageDead(_3);                 // scope 1 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
diff --git a/tests/mir-opt/const_prop/optimizes_into_variable.main.ScalarReplacementOfAggregates.64bit.diff b/tests/mir-opt/const_prop/optimizes_into_variable.main.ScalarReplacementOfAggregates.64bit.diff
index 3f9f3b2ea..98cd020da 100644
--- a/tests/mir-opt/const_prop/optimizes_into_variable.main.ScalarReplacementOfAggregates.64bit.diff
+++ b/tests/mir-opt/const_prop/optimizes_into_variable.main.ScalarReplacementOfAggregates.64bit.diff
@@ -48,20 +48,19 @@
           StorageDead(_4);                 // scope 1 at $DIR/optimizes_into_variable.rs:+2:34: +2:35
           StorageLive(_8);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
 -         StorageLive(_9);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
--         Deinit(_9);                      // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
--         (_9.0: u32) = const 12_u32;      // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
--         (_9.1: u32) = const 42_u32;      // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
+-         _9 = Point { x: const 12_u32, y: const 42_u32 }; // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
 -         _8 = (_9.1: u32);                // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:38
 -         StorageDead(_9);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:38: +3:39
 +         StorageLive(_10);                // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
 +         StorageLive(_11);                // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
-+         Deinit(_10);                     // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
-+         Deinit(_11);                     // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
++         nop;                             // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
 +         _10 = const 12_u32;              // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
 +         _11 = const 42_u32;              // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
++         nop;                             // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
 +         _8 = _11;                        // scope 2 at $DIR/optimizes_into_variable.rs:+3:13: +3:38
 +         StorageDead(_10);                // scope 2 at $DIR/optimizes_into_variable.rs:+3:38: +3:39
 +         StorageDead(_11);                // scope 2 at $DIR/optimizes_into_variable.rs:+3:38: +3:39
++         nop;                             // scope 2 at $DIR/optimizes_into_variable.rs:+3:38: +3:39
           nop;                             // scope 0 at $DIR/optimizes_into_variable.rs:+0:11: +4:2
           StorageDead(_8);                 // scope 2 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
           StorageDead(_3);                 // scope 1 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
diff --git a/tests/mir-opt/const_prop/optimizes_into_variable.main.SimplifyLocals-final.after.32bit.mir b/tests/mir-opt/const_prop/optimizes_into_variable.main.SimplifyLocals-final.after.32bit.mir
index d926b9df7..002e914e8 100644
--- a/tests/mir-opt/const_prop/optimizes_into_variable.main.SimplifyLocals-final.after.32bit.mir
+++ b/tests/mir-opt/const_prop/optimizes_into_variable.main.SimplifyLocals-final.after.32bit.mir
@@ -3,12 +3,12 @@
 fn main() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/optimizes_into_variable.rs:+0:11: +0:11
     let _1: i32;                         // in scope 0 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
+    let mut _3: u32;                     // in scope 0 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
     scope 1 {
         debug x => _1;                   // in scope 1 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
         let _2: i32;                     // in scope 1 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
         scope 2 {
             debug y => _2;               // in scope 2 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
-            let _3: u32;                 // in scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
             scope 3 {
                 debug z => _3;           // in scope 3 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
             }
@@ -18,8 +18,6 @@ fn main() -> () {
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
         StorageLive(_2);                 // scope 1 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
-        StorageLive(_3);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
-        StorageDead(_3);                 // scope 2 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         StorageDead(_2);                 // scope 1 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         StorageDead(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         return;                          // scope 0 at $DIR/optimizes_into_variable.rs:+4:2: +4:2
diff --git a/tests/mir-opt/const_prop/optimizes_into_variable.main.SimplifyLocals-final.after.64bit.mir b/tests/mir-opt/const_prop/optimizes_into_variable.main.SimplifyLocals-final.after.64bit.mir
index d926b9df7..002e914e8 100644
--- a/tests/mir-opt/const_prop/optimizes_into_variable.main.SimplifyLocals-final.after.64bit.mir
+++ b/tests/mir-opt/const_prop/optimizes_into_variable.main.SimplifyLocals-final.after.64bit.mir
@@ -3,12 +3,12 @@
 fn main() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/optimizes_into_variable.rs:+0:11: +0:11
     let _1: i32;                         // in scope 0 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
+    let mut _3: u32;                     // in scope 0 at $DIR/optimizes_into_variable.rs:+3:13: +3:36
     scope 1 {
         debug x => _1;                   // in scope 1 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
         let _2: i32;                     // in scope 1 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
         scope 2 {
             debug y => _2;               // in scope 2 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
-            let _3: u32;                 // in scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
             scope 3 {
                 debug z => _3;           // in scope 3 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
             }
@@ -18,8 +18,6 @@ fn main() -> () {
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:+1:9: +1:10
         StorageLive(_2);                 // scope 1 at $DIR/optimizes_into_variable.rs:+2:9: +2:10
-        StorageLive(_3);                 // scope 2 at $DIR/optimizes_into_variable.rs:+3:9: +3:10
-        StorageDead(_3);                 // scope 2 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         StorageDead(_2);                 // scope 1 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         StorageDead(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:+4:1: +4:2
         return;                          // scope 0 at $DIR/optimizes_into_variable.rs:+4:2: +4:2
diff --git a/tests/mir-opt/const_prop/ref_deref.main.ConstProp.diff b/tests/mir-opt/const_prop/ref_deref.main.ConstProp.diff
index 8a73f0390..924a267f3 100644
--- a/tests/mir-opt/const_prop/ref_deref.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/ref_deref.main.ConstProp.diff
@@ -13,14 +13,13 @@
           StorageLive(_2);                 // scope 0 at $DIR/ref_deref.rs:+1:6: +1:10
           _4 = const _;                    // scope 0 at $DIR/ref_deref.rs:+1:6: +1:10
                                            // mir::Constant
-                                           // + span: $DIR/ref_deref.rs:6:6: 6:10
+                                           // + span: $DIR/ref_deref.rs:5:6: 5:10
                                            // + literal: Const { ty: &i32, val: Unevaluated(main, [], Some(promoted[0])) }
-          _2 = _4;                         // scope 0 at $DIR/ref_deref.rs:+1:6: +1:10
--         _1 = (*_2);                      // scope 0 at $DIR/ref_deref.rs:+1:5: +1:10
-+         _1 = const 4_i32;                // scope 0 at $DIR/ref_deref.rs:+1:5: +1:10
+          _2 = &(*_4);                     // scope 0 at $DIR/ref_deref.rs:+1:6: +1:10
+          _1 = (*_2);                      // scope 0 at $DIR/ref_deref.rs:+1:5: +1:10
           StorageDead(_2);                 // scope 0 at $DIR/ref_deref.rs:+1:10: +1:11
           StorageDead(_1);                 // scope 0 at $DIR/ref_deref.rs:+1:10: +1:11
-          nop;                             // scope 0 at $DIR/ref_deref.rs:+0:11: +2:2
+          _0 = const ();                   // scope 0 at $DIR/ref_deref.rs:+0:11: +2:2
           return;                          // scope 0 at $DIR/ref_deref.rs:+2:2: +2:2
       }
   }
diff --git a/tests/mir-opt/const_prop/ref_deref.main.PromoteTemps.diff b/tests/mir-opt/const_prop/ref_deref.main.PromoteTemps.diff
deleted file mode 100644
index 015ec4d07..000000000
--- a/tests/mir-opt/const_prop/ref_deref.main.PromoteTemps.diff
+++ /dev/null
@@ -1,30 +0,0 @@
-- // MIR for `main` before PromoteTemps
-+ // MIR for `main` after PromoteTemps
-  
-  fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/ref_deref.rs:+0:11: +0:11
-      let _1: i32;                         // in scope 0 at $DIR/ref_deref.rs:+1:5: +1:10
-      let mut _2: &i32;                    // in scope 0 at $DIR/ref_deref.rs:+1:6: +1:10
-      let _3: i32;                         // in scope 0 at $DIR/ref_deref.rs:+1:8: +1:9
-+     let mut _4: &i32;                    // in scope 0 at $DIR/ref_deref.rs:+1:6: +1:10
-  
-      bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/ref_deref.rs:+1:5: +1:10
-          StorageLive(_2);                 // scope 0 at $DIR/ref_deref.rs:+1:6: +1:10
--         StorageLive(_3);                 // scope 0 at $DIR/ref_deref.rs:+1:8: +1:9
--         _3 = const 4_i32;                // scope 0 at $DIR/ref_deref.rs:+1:8: +1:9
--         _2 = &_3;                        // scope 0 at $DIR/ref_deref.rs:+1:6: +1:10
-+         _4 = const _;                    // scope 0 at $DIR/ref_deref.rs:+1:6: +1:10
-+                                          // mir::Constant
-+                                          // + span: $DIR/ref_deref.rs:6:6: 6:10
-+                                          // + literal: Const { ty: &i32, val: Unevaluated(main, [], Some(promoted[0])) }
-+         _2 = &(*_4);                     // scope 0 at $DIR/ref_deref.rs:+1:6: +1:10
-          _1 = (*_2);                      // scope 0 at $DIR/ref_deref.rs:+1:5: +1:10
--         StorageDead(_3);                 // scope 0 at $DIR/ref_deref.rs:+1:10: +1:11
-          StorageDead(_2);                 // scope 0 at $DIR/ref_deref.rs:+1:10: +1:11
-          StorageDead(_1);                 // scope 0 at $DIR/ref_deref.rs:+1:10: +1:11
-          _0 = const ();                   // scope 0 at $DIR/ref_deref.rs:+0:11: +2:2
-          return;                          // scope 0 at $DIR/ref_deref.rs:+2:2: +2:2
-      }
-  }
-  
diff --git a/tests/mir-opt/const_prop/ref_deref.rs b/tests/mir-opt/const_prop/ref_deref.rs
index d2549c8b6..76e56916a 100644
--- a/tests/mir-opt/const_prop/ref_deref.rs
+++ b/tests/mir-opt/const_prop/ref_deref.rs
@@ -1,5 +1,4 @@
-// compile-flags: -Zmir-enable-passes=-SimplifyLocals-before-const-prop
-// EMIT_MIR ref_deref.main.PromoteTemps.diff
+// unit-test: ConstProp
 // EMIT_MIR ref_deref.main.ConstProp.diff
 
 fn main() {
diff --git a/tests/mir-opt/const_prop/ref_deref_project.main.ConstProp.diff b/tests/mir-opt/const_prop/ref_deref_project.main.ConstProp.diff
index ec3d90433..59095b448 100644
--- a/tests/mir-opt/const_prop/ref_deref_project.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/ref_deref_project.main.ConstProp.diff
@@ -13,13 +13,13 @@
           StorageLive(_2);                 // scope 0 at $DIR/ref_deref_project.rs:+1:6: +1:17
           _4 = const _;                    // scope 0 at $DIR/ref_deref_project.rs:+1:6: +1:17
                                            // mir::Constant
-                                           // + span: $DIR/ref_deref_project.rs:6:6: 6:17
+                                           // + span: $DIR/ref_deref_project.rs:5:6: 5:17
                                            // + literal: Const { ty: &(i32, i32), val: Unevaluated(main, [], Some(promoted[0])) }
           _2 = &((*_4).1: i32);            // scope 0 at $DIR/ref_deref_project.rs:+1:6: +1:17
           _1 = (*_2);                      // scope 0 at $DIR/ref_deref_project.rs:+1:5: +1:17
           StorageDead(_2);                 // scope 0 at $DIR/ref_deref_project.rs:+1:17: +1:18
           StorageDead(_1);                 // scope 0 at $DIR/ref_deref_project.rs:+1:17: +1:18
-          nop;                             // scope 0 at $DIR/ref_deref_project.rs:+0:11: +2:2
+          _0 = const ();                   // scope 0 at $DIR/ref_deref_project.rs:+0:11: +2:2
           return;                          // scope 0 at $DIR/ref_deref_project.rs:+2:2: +2:2
       }
   }
diff --git a/tests/mir-opt/const_prop/ref_deref_project.main.PromoteTemps.diff b/tests/mir-opt/const_prop/ref_deref_project.main.PromoteTemps.diff
deleted file mode 100644
index cd0616e65..000000000
--- a/tests/mir-opt/const_prop/ref_deref_project.main.PromoteTemps.diff
+++ /dev/null
@@ -1,30 +0,0 @@
-- // MIR for `main` before PromoteTemps
-+ // MIR for `main` after PromoteTemps
-  
-  fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/ref_deref_project.rs:+0:11: +0:11
-      let _1: i32;                         // in scope 0 at $DIR/ref_deref_project.rs:+1:5: +1:17
-      let mut _2: &i32;                    // in scope 0 at $DIR/ref_deref_project.rs:+1:6: +1:17
-      let _3: (i32, i32);                  // in scope 0 at $DIR/ref_deref_project.rs:+1:8: +1:14
-+     let mut _4: &(i32, i32);             // in scope 0 at $DIR/ref_deref_project.rs:+1:6: +1:17
-  
-      bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/ref_deref_project.rs:+1:5: +1:17
-          StorageLive(_2);                 // scope 0 at $DIR/ref_deref_project.rs:+1:6: +1:17
--         StorageLive(_3);                 // scope 0 at $DIR/ref_deref_project.rs:+1:8: +1:14
--         _3 = (const 4_i32, const 5_i32); // scope 0 at $DIR/ref_deref_project.rs:+1:8: +1:14
--         _2 = &(_3.1: i32);               // scope 0 at $DIR/ref_deref_project.rs:+1:6: +1:17
-+         _4 = const _;                    // scope 0 at $DIR/ref_deref_project.rs:+1:6: +1:17
-+                                          // mir::Constant
-+                                          // + span: $DIR/ref_deref_project.rs:6:6: 6:17
-+                                          // + literal: Const { ty: &(i32, i32), val: Unevaluated(main, [], Some(promoted[0])) }
-+         _2 = &((*_4).1: i32);            // scope 0 at $DIR/ref_deref_project.rs:+1:6: +1:17
-          _1 = (*_2);                      // scope 0 at $DIR/ref_deref_project.rs:+1:5: +1:17
--         StorageDead(_3);                 // scope 0 at $DIR/ref_deref_project.rs:+1:17: +1:18
-          StorageDead(_2);                 // scope 0 at $DIR/ref_deref_project.rs:+1:17: +1:18
-          StorageDead(_1);                 // scope 0 at $DIR/ref_deref_project.rs:+1:17: +1:18
-          _0 = const ();                   // scope 0 at $DIR/ref_deref_project.rs:+0:11: +2:2
-          return;                          // scope 0 at $DIR/ref_deref_project.rs:+2:2: +2:2
-      }
-  }
-  
diff --git a/tests/mir-opt/const_prop/ref_deref_project.rs b/tests/mir-opt/const_prop/ref_deref_project.rs
index 2fdd4e153..04fc7f8da 100644
--- a/tests/mir-opt/const_prop/ref_deref_project.rs
+++ b/tests/mir-opt/const_prop/ref_deref_project.rs
@@ -1,5 +1,4 @@
-// compile-flags: -Zmir-enable-passes=-SimplifyLocals-before-const-prop
-// EMIT_MIR ref_deref_project.main.PromoteTemps.diff
+// unit-test: ConstProp
 // EMIT_MIR ref_deref_project.main.ConstProp.diff
 
 fn main() {
diff --git a/tests/mir-opt/const_prop/scalar_literal_propagation.main.ConstProp.diff b/tests/mir-opt/const_prop/scalar_literal_propagation.main.ConstProp.diff
index d518eff04..22f710387 100644
--- a/tests/mir-opt/const_prop/scalar_literal_propagation.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/scalar_literal_propagation.main.ConstProp.diff
@@ -11,13 +11,9 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/scalar_literal_propagation.rs:+1:9: +1:10
           _1 = const 1_u32;                // scope 0 at $DIR/scalar_literal_propagation.rs:+1:13: +1:14
           StorageLive(_2);                 // scope 1 at $DIR/scalar_literal_propagation.rs:+2:5: +2:15
-          StorageLive(_3);                 // scope 1 at $DIR/scalar_literal_propagation.rs:+2:13: +2:14
--         _3 = _1;                         // scope 1 at $DIR/scalar_literal_propagation.rs:+2:13: +2:14
--         _2 = consume(move _3) -> bb1;    // scope 1 at $DIR/scalar_literal_propagation.rs:+2:5: +2:15
-+         _3 = const 1_u32;                // scope 1 at $DIR/scalar_literal_propagation.rs:+2:13: +2:14
+-         _2 = consume(_1) -> bb1;         // scope 1 at $DIR/scalar_literal_propagation.rs:+2:5: +2:15
 +         _2 = consume(const 1_u32) -> bb1; // scope 1 at $DIR/scalar_literal_propagation.rs:+2:5: +2:15
                                            // mir::Constant
                                            // + span: $DIR/scalar_literal_propagation.rs:4:5: 4:12
@@ -25,9 +21,7 @@
       }
   
       bb1: {
-          StorageDead(_3);                 // scope 1 at $DIR/scalar_literal_propagation.rs:+2:14: +2:15
           StorageDead(_2);                 // scope 1 at $DIR/scalar_literal_propagation.rs:+2:15: +2:16
-          StorageDead(_1);                 // scope 0 at $DIR/scalar_literal_propagation.rs:+3:1: +3:2
           return;                          // scope 0 at $DIR/scalar_literal_propagation.rs:+3:2: +3:2
       }
   }
diff --git a/tests/mir-opt/const_prop/slice_len.main.ConstProp.32bit.diff b/tests/mir-opt/const_prop/slice_len.main.ConstProp.32bit.diff
index 9017fd18e..b99b83b0c 100644
--- a/tests/mir-opt/const_prop/slice_len.main.ConstProp.32bit.diff
+++ b/tests/mir-opt/const_prop/slice_len.main.ConstProp.32bit.diff
@@ -20,7 +20,7 @@
           StorageLive(_4);                 // scope 0 at $DIR/slice_len.rs:+1:6: +1:19
           _9 = const _;                    // scope 0 at $DIR/slice_len.rs:+1:6: +1:19
                                            // mir::Constant
-                                           // + span: $DIR/slice_len.rs:6:6: 6:19
+                                           // + span: $DIR/slice_len.rs:7:6: 7:19
                                            // + literal: Const { ty: &[u32; 3], val: Unevaluated(main, [], Some(promoted[0])) }
           _4 = _9;                         // scope 0 at $DIR/slice_len.rs:+1:6: +1:19
           _3 = _4;                         // scope 0 at $DIR/slice_len.rs:+1:6: +1:19
@@ -33,7 +33,7 @@
 -         assert(move _8, "index out of bounds: the length is {} but the index is {}", move _7, _6) -> bb1; // scope 0 at $DIR/slice_len.rs:+1:5: +1:33
 +         _7 = const 3_usize;              // scope 0 at $DIR/slice_len.rs:+1:5: +1:33
 +         _8 = const true;                 // scope 0 at $DIR/slice_len.rs:+1:5: +1:33
-+         assert(const true, "index out of bounds: the length is {} but the index is {}", const 3_usize, const 1_usize) -> bb1; // scope 0 at $DIR/slice_len.rs:+1:5: +1:33
++         assert(const true, "index out of bounds: the length is {} but the index is {}", move _7, _6) -> bb1; // scope 0 at $DIR/slice_len.rs:+1:5: +1:33
       }
   
       bb1: {
@@ -43,7 +43,7 @@
           StorageDead(_4);                 // scope 0 at $DIR/slice_len.rs:+1:33: +1:34
           StorageDead(_2);                 // scope 0 at $DIR/slice_len.rs:+1:33: +1:34
           StorageDead(_1);                 // scope 0 at $DIR/slice_len.rs:+1:33: +1:34
-          nop;                             // scope 0 at $DIR/slice_len.rs:+0:11: +2:2
+          _0 = const ();                   // scope 0 at $DIR/slice_len.rs:+0:11: +2:2
           return;                          // scope 0 at $DIR/slice_len.rs:+2:2: +2:2
       }
   }
diff --git a/tests/mir-opt/const_prop/slice_len.main.ConstProp.64bit.diff b/tests/mir-opt/const_prop/slice_len.main.ConstProp.64bit.diff
index 9017fd18e..b99b83b0c 100644
--- a/tests/mir-opt/const_prop/slice_len.main.ConstProp.64bit.diff
+++ b/tests/mir-opt/const_prop/slice_len.main.ConstProp.64bit.diff
@@ -20,7 +20,7 @@
           StorageLive(_4);                 // scope 0 at $DIR/slice_len.rs:+1:6: +1:19
           _9 = const _;                    // scope 0 at $DIR/slice_len.rs:+1:6: +1:19
                                            // mir::Constant
-                                           // + span: $DIR/slice_len.rs:6:6: 6:19
+                                           // + span: $DIR/slice_len.rs:7:6: 7:19
                                            // + literal: Const { ty: &[u32; 3], val: Unevaluated(main, [], Some(promoted[0])) }
           _4 = _9;                         // scope 0 at $DIR/slice_len.rs:+1:6: +1:19
           _3 = _4;                         // scope 0 at $DIR/slice_len.rs:+1:6: +1:19
@@ -33,7 +33,7 @@
 -         assert(move _8, "index out of bounds: the length is {} but the index is {}", move _7, _6) -> bb1; // scope 0 at $DIR/slice_len.rs:+1:5: +1:33
 +         _7 = const 3_usize;              // scope 0 at $DIR/slice_len.rs:+1:5: +1:33
 +         _8 = const true;                 // scope 0 at $DIR/slice_len.rs:+1:5: +1:33
-+         assert(const true, "index out of bounds: the length is {} but the index is {}", const 3_usize, const 1_usize) -> bb1; // scope 0 at $DIR/slice_len.rs:+1:5: +1:33
++         assert(const true, "index out of bounds: the length is {} but the index is {}", move _7, _6) -> bb1; // scope 0 at $DIR/slice_len.rs:+1:5: +1:33
       }
   
       bb1: {
@@ -43,7 +43,7 @@
           StorageDead(_4);                 // scope 0 at $DIR/slice_len.rs:+1:33: +1:34
           StorageDead(_2);                 // scope 0 at $DIR/slice_len.rs:+1:33: +1:34
           StorageDead(_1);                 // scope 0 at $DIR/slice_len.rs:+1:33: +1:34
-          nop;                             // scope 0 at $DIR/slice_len.rs:+0:11: +2:2
+          _0 = const ();                   // scope 0 at $DIR/slice_len.rs:+0:11: +2:2
           return;                          // scope 0 at $DIR/slice_len.rs:+2:2: +2:2
       }
   }
diff --git a/tests/mir-opt/const_prop/slice_len.rs b/tests/mir-opt/const_prop/slice_len.rs
index eaaf34b96..8183def0c 100644
--- a/tests/mir-opt/const_prop/slice_len.rs
+++ b/tests/mir-opt/const_prop/slice_len.rs
@@ -1,4 +1,5 @@
-// compile-flags: -Zmir-enable-passes=-SimplifyLocals-before-const-prop
+// unit-test: ConstProp
+// compile-flags: -Zmir-enable-passes=+InstCombine
 // EMIT_MIR_FOR_EACH_BIT_WIDTH
 
 // EMIT_MIR slice_len.main.ConstProp.diff
diff --git a/tests/mir-opt/const_prop/tuple_literal_propagation.main.ConstProp.diff b/tests/mir-opt/const_prop/tuple_literal_propagation.main.ConstProp.diff
index e4c92b617..270a1ccf5 100644
--- a/tests/mir-opt/const_prop/tuple_literal_propagation.main.ConstProp.diff
+++ b/tests/mir-opt/const_prop/tuple_literal_propagation.main.ConstProp.diff
@@ -11,24 +11,17 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/tuple_literal_propagation.rs:+1:9: +1:10
-          Deinit(_1);                      // scope 0 at $DIR/tuple_literal_propagation.rs:+1:13: +1:19
-          (_1.0: u32) = const 1_u32;       // scope 0 at $DIR/tuple_literal_propagation.rs:+1:13: +1:19
-          (_1.1: u32) = const 2_u32;       // scope 0 at $DIR/tuple_literal_propagation.rs:+1:13: +1:19
+-         _1 = (const 1_u32, const 2_u32); // scope 0 at $DIR/tuple_literal_propagation.rs:+1:13: +1:19
++         _1 = const (1_u32, 2_u32);       // scope 0 at $DIR/tuple_literal_propagation.rs:+1:13: +1:19
           StorageLive(_2);                 // scope 1 at $DIR/tuple_literal_propagation.rs:+3:5: +3:15
-          StorageLive(_3);                 // scope 1 at $DIR/tuple_literal_propagation.rs:+3:13: +3:14
--         _3 = _1;                         // scope 1 at $DIR/tuple_literal_propagation.rs:+3:13: +3:14
-+         _3 = const (1_u32, 2_u32);       // scope 1 at $DIR/tuple_literal_propagation.rs:+3:13: +3:14
-          _2 = consume(move _3) -> bb1;    // scope 1 at $DIR/tuple_literal_propagation.rs:+3:5: +3:15
+          _2 = consume(_1) -> bb1;         // scope 1 at $DIR/tuple_literal_propagation.rs:+3:5: +3:15
                                            // mir::Constant
                                            // + span: $DIR/tuple_literal_propagation.rs:5:5: 5:12
                                            // + literal: Const { ty: fn((u32, u32)) {consume}, val: Value(<ZST>) }
       }
   
       bb1: {
-          StorageDead(_3);                 // scope 1 at $DIR/tuple_literal_propagation.rs:+3:14: +3:15
           StorageDead(_2);                 // scope 1 at $DIR/tuple_literal_propagation.rs:+3:15: +3:16
-          StorageDead(_1);                 // scope 0 at $DIR/tuple_literal_propagation.rs:+4:1: +4:2
           return;                          // scope 0 at $DIR/tuple_literal_propagation.rs:+4:2: +4:2
       }
   }
diff --git a/tests/mir-opt/const_prop_miscompile.bar.ConstProp.diff b/tests/mir-opt/const_prop_miscompile.bar.ConstProp.diff
index ea9fec0aa..def9fc642 100644
--- a/tests/mir-opt/const_prop_miscompile.bar.ConstProp.diff
+++ b/tests/mir-opt/const_prop_miscompile.bar.ConstProp.diff
@@ -4,32 +4,37 @@
   fn bar() -> () {
       let mut _0: ();                      // return place in scope 0 at $DIR/const_prop_miscompile.rs:+0:10: +0:10
       let mut _1: (i32,);                  // in scope 0 at $DIR/const_prop_miscompile.rs:+1:9: +1:14
-      let mut _2: *mut i32;                // in scope 0 at $DIR/const_prop_miscompile.rs:+3:10: +3:22
-      let mut _4: i32;                     // in scope 0 at $DIR/const_prop_miscompile.rs:+5:13: +5:20
+      let _2: ();                          // in scope 0 at $DIR/const_prop_miscompile.rs:+2:5: +4:6
+      let mut _3: *mut i32;                // in scope 0 at $DIR/const_prop_miscompile.rs:+3:10: +3:22
+      let mut _5: i32;                     // in scope 0 at $DIR/const_prop_miscompile.rs:+5:13: +5:20
       scope 1 {
           debug v => _1;                   // in scope 1 at $DIR/const_prop_miscompile.rs:+1:9: +1:14
-          let _3: bool;                    // in scope 1 at $DIR/const_prop_miscompile.rs:+5:9: +5:10
+          let _4: bool;                    // in scope 1 at $DIR/const_prop_miscompile.rs:+5:9: +5:10
           scope 2 {
           }
           scope 3 {
-              debug y => _3;               // in scope 3 at $DIR/const_prop_miscompile.rs:+5:9: +5:10
+              debug y => _4;               // in scope 3 at $DIR/const_prop_miscompile.rs:+5:9: +5:10
           }
       }
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/const_prop_miscompile.rs:+1:9: +1:14
-          Deinit(_1);                      // scope 0 at $DIR/const_prop_miscompile.rs:+1:17: +1:21
-          (_1.0: i32) = const 1_i32;       // scope 0 at $DIR/const_prop_miscompile.rs:+1:17: +1:21
-          StorageLive(_2);                 // scope 2 at $DIR/const_prop_miscompile.rs:+3:10: +3:22
-          _2 = &raw mut (_1.0: i32);       // scope 2 at $DIR/const_prop_miscompile.rs:+3:10: +3:22
-          (*_2) = const 5_i32;             // scope 2 at $DIR/const_prop_miscompile.rs:+3:9: +3:26
-          StorageDead(_2);                 // scope 2 at $DIR/const_prop_miscompile.rs:+3:26: +3:27
-          StorageLive(_3);                 // scope 1 at $DIR/const_prop_miscompile.rs:+5:9: +5:10
-          StorageLive(_4);                 // scope 1 at $DIR/const_prop_miscompile.rs:+5:13: +5:20
-          _4 = (_1.0: i32);                // scope 1 at $DIR/const_prop_miscompile.rs:+5:15: +5:18
-          _3 = Eq(move _4, const 5_i32);   // scope 1 at $DIR/const_prop_miscompile.rs:+5:13: +5:25
-          StorageDead(_4);                 // scope 1 at $DIR/const_prop_miscompile.rs:+5:24: +5:25
-          StorageDead(_3);                 // scope 1 at $DIR/const_prop_miscompile.rs:+6:1: +6:2
+-         _1 = (const 1_i32,);             // scope 0 at $DIR/const_prop_miscompile.rs:+1:17: +1:21
++         _1 = const (1_i32,);             // scope 0 at $DIR/const_prop_miscompile.rs:+1:17: +1:21
+          StorageLive(_2);                 // scope 1 at $DIR/const_prop_miscompile.rs:+2:5: +4:6
+          StorageLive(_3);                 // scope 2 at $DIR/const_prop_miscompile.rs:+3:10: +3:22
+          _3 = &raw mut (_1.0: i32);       // scope 2 at $DIR/const_prop_miscompile.rs:+3:10: +3:22
+          (*_3) = const 5_i32;             // scope 2 at $DIR/const_prop_miscompile.rs:+3:9: +3:26
+          StorageDead(_3);                 // scope 2 at $DIR/const_prop_miscompile.rs:+3:26: +3:27
+          _2 = const ();                   // scope 2 at $DIR/const_prop_miscompile.rs:+2:5: +4:6
+          StorageDead(_2);                 // scope 1 at $DIR/const_prop_miscompile.rs:+4:5: +4:6
+          StorageLive(_4);                 // scope 1 at $DIR/const_prop_miscompile.rs:+5:9: +5:10
+          StorageLive(_5);                 // scope 1 at $DIR/const_prop_miscompile.rs:+5:13: +5:20
+          _5 = (_1.0: i32);                // scope 1 at $DIR/const_prop_miscompile.rs:+5:15: +5:18
+          _4 = Eq(move _5, const 5_i32);   // scope 1 at $DIR/const_prop_miscompile.rs:+5:13: +5:25
+          StorageDead(_5);                 // scope 1 at $DIR/const_prop_miscompile.rs:+5:24: +5:25
+          _0 = const ();                   // scope 0 at $DIR/const_prop_miscompile.rs:+0:10: +6:2
+          StorageDead(_4);                 // scope 1 at $DIR/const_prop_miscompile.rs:+6:1: +6:2
           StorageDead(_1);                 // scope 0 at $DIR/const_prop_miscompile.rs:+6:1: +6:2
           return;                          // scope 0 at $DIR/const_prop_miscompile.rs:+6:2: +6:2
       }
diff --git a/tests/mir-opt/const_prop_miscompile.foo.ConstProp.diff b/tests/mir-opt/const_prop_miscompile.foo.ConstProp.diff
index 043f40474..b54c10a14 100644
--- a/tests/mir-opt/const_prop_miscompile.foo.ConstProp.diff
+++ b/tests/mir-opt/const_prop_miscompile.foo.ConstProp.diff
@@ -16,8 +16,8 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/const_prop_miscompile.rs:+1:9: +1:14
-          Deinit(_1);                      // scope 0 at $DIR/const_prop_miscompile.rs:+1:17: +1:21
-          (_1.0: i32) = const 1_i32;       // scope 0 at $DIR/const_prop_miscompile.rs:+1:17: +1:21
+-         _1 = (const 1_i32,);             // scope 0 at $DIR/const_prop_miscompile.rs:+1:17: +1:21
++         _1 = const (1_i32,);             // scope 0 at $DIR/const_prop_miscompile.rs:+1:17: +1:21
           StorageLive(_2);                 // scope 1 at $DIR/const_prop_miscompile.rs:+2:6: +2:14
           _2 = &mut (_1.0: i32);           // scope 1 at $DIR/const_prop_miscompile.rs:+2:6: +2:14
           (*_2) = const 5_i32;             // scope 1 at $DIR/const_prop_miscompile.rs:+2:5: +2:18
@@ -27,6 +27,7 @@
           _4 = (_1.0: i32);                // scope 1 at $DIR/const_prop_miscompile.rs:+3:15: +3:18
           _3 = Eq(move _4, const 5_i32);   // scope 1 at $DIR/const_prop_miscompile.rs:+3:13: +3:25
           StorageDead(_4);                 // scope 1 at $DIR/const_prop_miscompile.rs:+3:24: +3:25
+          _0 = const ();                   // scope 0 at $DIR/const_prop_miscompile.rs:+0:10: +4:2
           StorageDead(_3);                 // scope 1 at $DIR/const_prop_miscompile.rs:+4:1: +4:2
           StorageDead(_1);                 // scope 0 at $DIR/const_prop_miscompile.rs:+4:1: +4:2
           return;                          // scope 0 at $DIR/const_prop_miscompile.rs:+4:2: +4:2
diff --git a/tests/mir-opt/const_prop_miscompile.rs b/tests/mir-opt/const_prop_miscompile.rs
index bc54556b3..dbbe5ee08 100644
--- a/tests/mir-opt/const_prop_miscompile.rs
+++ b/tests/mir-opt/const_prop_miscompile.rs
@@ -1,3 +1,4 @@
+// unit-test: ConstProp
 #![feature(raw_ref_op)]
 
 // EMIT_MIR const_prop_miscompile.foo.ConstProp.diff
diff --git a/tests/mir-opt/copy-prop/borrowed_local.f.CopyProp.diff b/tests/mir-opt/copy-prop/borrowed_local.f.CopyProp.diff
new file mode 100644
index 000000000..b183865a9
--- /dev/null
+++ b/tests/mir-opt/copy-prop/borrowed_local.f.CopyProp.diff
@@ -0,0 +1,34 @@
+- // MIR for `f` before CopyProp
++ // MIR for `f` after CopyProp
+  
+  fn f() -> bool {
+      let mut _0: bool;                    // return place in scope 0 at $DIR/borrowed_local.rs:+0:11: +0:15
+      let mut _1: u8;                      // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+      let mut _2: &u8;                     // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+      let mut _3: u8;                      // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+      let mut _4: &u8;                     // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+  
+      bb0: {
+          _1 = const 5_u8;                 // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+          _2 = &_1;                        // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+          _3 = _1;                         // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+          _4 = &_3;                        // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+          _0 = cmp_ref(_2, _4) -> bb1;     // scope 0 at $DIR/borrowed_local.rs:+8:13: +8:45
+                                           // mir::Constant
+                                           // + span: $DIR/borrowed_local.rs:23:29: 23:36
+                                           // + literal: Const { ty: for<'a, 'b> fn(&'a u8, &'b u8) -> bool {cmp_ref}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+-         _0 = opaque::<u8>(_3) -> bb2;    // scope 0 at $DIR/borrowed_local.rs:+12:13: +12:38
++         _0 = opaque::<u8>(_1) -> bb2;    // scope 0 at $DIR/borrowed_local.rs:+12:13: +12:38
+                                           // mir::Constant
+                                           // + span: $DIR/borrowed_local.rs:27:28: 27:34
+                                           // + literal: Const { ty: fn(u8) -> bool {opaque::<u8>}, val: Value(<ZST>) }
+      }
+  
+      bb2: {
+          return;                          // scope 0 at $DIR/borrowed_local.rs:+15:13: +15:21
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/borrowed_local.rs b/tests/mir-opt/copy-prop/borrowed_local.rs
new file mode 100644
index 000000000..c4b980e2b
--- /dev/null
+++ b/tests/mir-opt/copy-prop/borrowed_local.rs
@@ -0,0 +1,39 @@
+// unit-test: CopyProp
+
+#![feature(custom_mir, core_intrinsics)]
+#![allow(unused_assignments)]
+extern crate core;
+use core::intrinsics::mir::*;
+
+fn opaque(_: impl Sized) -> bool { true }
+
+fn cmp_ref(a: &u8, b: &u8) -> bool {
+    std::ptr::eq(a as *const u8, b as *const u8)
+}
+
+#[custom_mir(dialect = "analysis", phase = "post-cleanup")]
+fn f() -> bool {
+    mir!(
+        {
+            let a = 5_u8;
+            let r1 = &a;
+            let b = a;
+            // We cannot propagate the place `a`.
+            let r2 = &b;
+            Call(RET, next, cmp_ref(r1, r2))
+        }
+        next = {
+            // But we can propagate the value `a`.
+            Call(RET, ret, opaque(b))
+        }
+        ret = {
+            Return()
+        }
+    )
+}
+
+fn main() {
+    assert!(!f());
+}
+
+// EMIT_MIR borrowed_local.f.CopyProp.diff
diff --git a/tests/mir-opt/copy-prop/branch.foo.CopyProp.diff b/tests/mir-opt/copy-prop/branch.foo.CopyProp.diff
new file mode 100644
index 000000000..8b116532d
--- /dev/null
+++ b/tests/mir-opt/copy-prop/branch.foo.CopyProp.diff
@@ -0,0 +1,65 @@
+- // MIR for `foo` before CopyProp
++ // MIR for `foo` after CopyProp
+  
+  fn foo() -> i32 {
+      let mut _0: i32;                     // return place in scope 0 at $DIR/branch.rs:+0:13: +0:16
+      let _1: i32;                         // in scope 0 at $DIR/branch.rs:+1:9: +1:10
+      let mut _3: bool;                    // in scope 0 at $DIR/branch.rs:+3:16: +3:22
+      let _4: i32;                         // in scope 0 at $DIR/branch.rs:+6:9: +6:14
+      scope 1 {
+          debug x => _1;                   // in scope 1 at $DIR/branch.rs:+1:9: +1:10
+          let _2: i32;                     // in scope 1 at $DIR/branch.rs:+3:9: +3:10
+          scope 2 {
+              debug y => _2;               // in scope 2 at $DIR/branch.rs:+3:9: +3:10
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/branch.rs:+1:9: +1:10
+          _1 = val() -> bb1;               // scope 0 at $DIR/branch.rs:+1:13: +1:18
+                                           // mir::Constant
+                                           // + span: $DIR/branch.rs:13:13: 13:16
+                                           // + literal: Const { ty: fn() -> i32 {val}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageLive(_2);                 // scope 1 at $DIR/branch.rs:+3:9: +3:10
+          StorageLive(_3);                 // scope 1 at $DIR/branch.rs:+3:16: +3:22
+          _3 = cond() -> bb2;              // scope 1 at $DIR/branch.rs:+3:16: +3:22
+                                           // mir::Constant
+                                           // + span: $DIR/branch.rs:15:16: 15:20
+                                           // + literal: Const { ty: fn() -> bool {cond}, val: Value(<ZST>) }
+      }
+  
+      bb2: {
+          switchInt(move _3) -> [0: bb4, otherwise: bb3]; // scope 1 at $DIR/branch.rs:+3:16: +3:22
+      }
+  
+      bb3: {
+          _2 = _1;                         // scope 1 at $DIR/branch.rs:+4:9: +4:10
+          goto -> bb6;                     // scope 1 at $DIR/branch.rs:+3:13: +8:6
+      }
+  
+      bb4: {
+          StorageLive(_4);                 // scope 1 at $DIR/branch.rs:+6:9: +6:14
+          _4 = val() -> bb5;               // scope 1 at $DIR/branch.rs:+6:9: +6:14
+                                           // mir::Constant
+                                           // + span: $DIR/branch.rs:18:9: 18:12
+                                           // + literal: Const { ty: fn() -> i32 {val}, val: Value(<ZST>) }
+      }
+  
+      bb5: {
+          StorageDead(_4);                 // scope 1 at $DIR/branch.rs:+6:14: +6:15
+          _2 = _1;                         // scope 1 at $DIR/branch.rs:+7:9: +7:10
+          goto -> bb6;                     // scope 1 at $DIR/branch.rs:+3:13: +8:6
+      }
+  
+      bb6: {
+          StorageDead(_3);                 // scope 1 at $DIR/branch.rs:+8:5: +8:6
+          _0 = _2;                         // scope 2 at $DIR/branch.rs:+10:5: +10:6
+          StorageDead(_2);                 // scope 1 at $DIR/branch.rs:+11:1: +11:2
+          StorageDead(_1);                 // scope 0 at $DIR/branch.rs:+11:1: +11:2
+          return;                          // scope 0 at $DIR/branch.rs:+11:2: +11:2
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/branch.rs b/tests/mir-opt/copy-prop/branch.rs
new file mode 100644
index 000000000..50b1e00fa
--- /dev/null
+++ b/tests/mir-opt/copy-prop/branch.rs
@@ -0,0 +1,27 @@
+//! Tests that we bail out when there are multiple assignments to the same local.
+// unit-test: CopyProp
+fn val() -> i32 {
+    1
+}
+
+fn cond() -> bool {
+    true
+}
+
+// EMIT_MIR branch.foo.CopyProp.diff
+fn foo() -> i32 {
+    let x = val();
+
+    let y = if cond() {
+        x
+    } else {
+        val();
+        x
+    };
+
+    y
+}
+
+fn main() {
+    foo();
+}
diff --git a/tests/mir-opt/copy-prop/copy_propagation_arg.arg_src.CopyProp.diff b/tests/mir-opt/copy-prop/copy_propagation_arg.arg_src.CopyProp.diff
new file mode 100644
index 000000000..69acebf76
--- /dev/null
+++ b/tests/mir-opt/copy-prop/copy_propagation_arg.arg_src.CopyProp.diff
@@ -0,0 +1,21 @@
+- // MIR for `arg_src` before CopyProp
++ // MIR for `arg_src` after CopyProp
+  
+  fn arg_src(_1: i32) -> i32 {
+      debug x => _1;                       // in scope 0 at $DIR/copy_propagation_arg.rs:+0:12: +0:17
+      let mut _0: i32;                     // return place in scope 0 at $DIR/copy_propagation_arg.rs:+0:27: +0:30
+      let _2: i32;                         // in scope 0 at $DIR/copy_propagation_arg.rs:+1:9: +1:10
+      scope 1 {
+          debug y => _2;                   // in scope 1 at $DIR/copy_propagation_arg.rs:+1:9: +1:10
+      }
+  
+      bb0: {
+          StorageLive(_2);                 // scope 0 at $DIR/copy_propagation_arg.rs:+1:9: +1:10
+          _2 = _1;                         // scope 0 at $DIR/copy_propagation_arg.rs:+1:13: +1:14
+          _1 = const 123_i32;              // scope 1 at $DIR/copy_propagation_arg.rs:+2:5: +2:12
+          _0 = _2;                         // scope 1 at $DIR/copy_propagation_arg.rs:+3:5: +3:6
+          StorageDead(_2);                 // scope 0 at $DIR/copy_propagation_arg.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/copy_propagation_arg.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/copy_propagation_arg.bar.CopyProp.diff b/tests/mir-opt/copy-prop/copy_propagation_arg.bar.CopyProp.diff
new file mode 100644
index 000000000..ac4e9a2bf
--- /dev/null
+++ b/tests/mir-opt/copy-prop/copy_propagation_arg.bar.CopyProp.diff
@@ -0,0 +1,28 @@
+- // MIR for `bar` before CopyProp
++ // MIR for `bar` after CopyProp
+  
+  fn bar(_1: u8) -> () {
+      debug x => _1;                       // in scope 0 at $DIR/copy_propagation_arg.rs:+0:8: +0:13
+      let mut _0: ();                      // return place in scope 0 at $DIR/copy_propagation_arg.rs:+0:19: +0:19
+      let _2: u8;                          // in scope 0 at $DIR/copy_propagation_arg.rs:+1:5: +1:13
+      let mut _3: u8;                      // in scope 0 at $DIR/copy_propagation_arg.rs:+1:11: +1:12
+  
+      bb0: {
+          StorageLive(_2);                 // scope 0 at $DIR/copy_propagation_arg.rs:+1:5: +1:13
+          StorageLive(_3);                 // scope 0 at $DIR/copy_propagation_arg.rs:+1:11: +1:12
+          _3 = _1;                         // scope 0 at $DIR/copy_propagation_arg.rs:+1:11: +1:12
+          _2 = dummy(move _3) -> bb1;      // scope 0 at $DIR/copy_propagation_arg.rs:+1:5: +1:13
+                                           // mir::Constant
+                                           // + span: $DIR/copy_propagation_arg.rs:16:5: 16:10
+                                           // + literal: Const { ty: fn(u8) -> u8 {dummy}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_3);                 // scope 0 at $DIR/copy_propagation_arg.rs:+1:12: +1:13
+          StorageDead(_2);                 // scope 0 at $DIR/copy_propagation_arg.rs:+1:13: +1:14
+          _1 = const 5_u8;                 // scope 0 at $DIR/copy_propagation_arg.rs:+2:5: +2:10
+          _0 = const ();                   // scope 0 at $DIR/copy_propagation_arg.rs:+0:19: +3:2
+          return;                          // scope 0 at $DIR/copy_propagation_arg.rs:+3:2: +3:2
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/copy_propagation_arg.baz.CopyProp.diff b/tests/mir-opt/copy-prop/copy_propagation_arg.baz.CopyProp.diff
new file mode 100644
index 000000000..7ab6ebb7d
--- /dev/null
+++ b/tests/mir-opt/copy-prop/copy_propagation_arg.baz.CopyProp.diff
@@ -0,0 +1,18 @@
+- // MIR for `baz` before CopyProp
++ // MIR for `baz` after CopyProp
+  
+  fn baz(_1: i32) -> i32 {
+      debug x => _1;                       // in scope 0 at $DIR/copy_propagation_arg.rs:+0:8: +0:13
+      let mut _0: i32;                     // return place in scope 0 at $DIR/copy_propagation_arg.rs:+0:23: +0:26
+      let mut _2: i32;                     // in scope 0 at $DIR/copy_propagation_arg.rs:+2:9: +2:10
+  
+      bb0: {
+          StorageLive(_2);                 // scope 0 at $DIR/copy_propagation_arg.rs:+2:9: +2:10
+          _2 = _1;                         // scope 0 at $DIR/copy_propagation_arg.rs:+2:9: +2:10
+          _1 = move _2;                    // scope 0 at $DIR/copy_propagation_arg.rs:+2:5: +2:10
+          StorageDead(_2);                 // scope 0 at $DIR/copy_propagation_arg.rs:+2:9: +2:10
+          _0 = _1;                         // scope 0 at $DIR/copy_propagation_arg.rs:+3:5: +3:6
+          return;                          // scope 0 at $DIR/copy_propagation_arg.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/copy_propagation_arg.foo.CopyProp.diff b/tests/mir-opt/copy-prop/copy_propagation_arg.foo.CopyProp.diff
new file mode 100644
index 000000000..0a3e985e7
--- /dev/null
+++ b/tests/mir-opt/copy-prop/copy_propagation_arg.foo.CopyProp.diff
@@ -0,0 +1,28 @@
+- // MIR for `foo` before CopyProp
++ // MIR for `foo` after CopyProp
+  
+  fn foo(_1: u8) -> () {
+      debug x => _1;                       // in scope 0 at $DIR/copy_propagation_arg.rs:+0:8: +0:13
+      let mut _0: ();                      // return place in scope 0 at $DIR/copy_propagation_arg.rs:+0:19: +0:19
+      let mut _2: u8;                      // in scope 0 at $DIR/copy_propagation_arg.rs:+2:9: +2:17
+      let mut _3: u8;                      // in scope 0 at $DIR/copy_propagation_arg.rs:+2:15: +2:16
+  
+      bb0: {
+          StorageLive(_2);                 // scope 0 at $DIR/copy_propagation_arg.rs:+2:9: +2:17
+          StorageLive(_3);                 // scope 0 at $DIR/copy_propagation_arg.rs:+2:15: +2:16
+          _3 = _1;                         // scope 0 at $DIR/copy_propagation_arg.rs:+2:15: +2:16
+          _2 = dummy(move _3) -> bb1;      // scope 0 at $DIR/copy_propagation_arg.rs:+2:9: +2:17
+                                           // mir::Constant
+                                           // + span: $DIR/copy_propagation_arg.rs:11:9: 11:14
+                                           // + literal: Const { ty: fn(u8) -> u8 {dummy}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_3);                 // scope 0 at $DIR/copy_propagation_arg.rs:+2:16: +2:17
+          _1 = move _2;                    // scope 0 at $DIR/copy_propagation_arg.rs:+2:5: +2:17
+          StorageDead(_2);                 // scope 0 at $DIR/copy_propagation_arg.rs:+2:16: +2:17
+          _0 = const ();                   // scope 0 at $DIR/copy_propagation_arg.rs:+0:19: +3:2
+          return;                          // scope 0 at $DIR/copy_propagation_arg.rs:+3:2: +3:2
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/copy_propagation_arg.rs b/tests/mir-opt/copy-prop/copy_propagation_arg.rs
new file mode 100644
index 000000000..cc98985f1
--- /dev/null
+++ b/tests/mir-opt/copy-prop/copy_propagation_arg.rs
@@ -0,0 +1,40 @@
+// Check that CopyProp does not propagate an assignment to a function argument
+// (doing so can break usages of the original argument value)
+// unit-test: CopyProp
+fn dummy(x: u8) -> u8 {
+    x
+}
+
+// EMIT_MIR copy_propagation_arg.foo.CopyProp.diff
+fn foo(mut x: u8) {
+    // calling `dummy` to make a use of `x` that copyprop cannot eliminate
+    x = dummy(x); // this will assign a local to `x`
+}
+
+// EMIT_MIR copy_propagation_arg.bar.CopyProp.diff
+fn bar(mut x: u8) {
+    dummy(x);
+    x = 5;
+}
+
+// EMIT_MIR copy_propagation_arg.baz.CopyProp.diff
+fn baz(mut x: i32) -> i32 {
+    // self-assignment to a function argument should be eliminated
+    x = x;
+    x
+}
+
+// EMIT_MIR copy_propagation_arg.arg_src.CopyProp.diff
+fn arg_src(mut x: i32) -> i32 {
+    let y = x;
+    x = 123; // Don't propagate this assignment to `y`
+    y
+}
+
+fn main() {
+    // Make sure the function actually gets instantiated.
+    foo(0);
+    bar(0);
+    baz(0);
+    arg_src(0);
+}
diff --git a/tests/mir-opt/copy-prop/custom_move_arg.f.CopyProp.diff b/tests/mir-opt/copy-prop/custom_move_arg.f.CopyProp.diff
new file mode 100644
index 000000000..6ca73ffdd
--- /dev/null
+++ b/tests/mir-opt/copy-prop/custom_move_arg.f.CopyProp.diff
@@ -0,0 +1,31 @@
+- // MIR for `f` before CopyProp
++ // MIR for `f` after CopyProp
+  
+  fn f(_1: NotCopy) -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/custom_move_arg.rs:+0:19: +0:19
+      let mut _2: NotCopy;                 // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+      let mut _3: NotCopy;                 // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+  
+      bb0: {
+-         _2 = _1;                         // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+-         _0 = opaque::<NotCopy>(move _1) -> bb1; // scope 0 at $DIR/custom_move_arg.rs:+3:9: +3:41
++         _0 = opaque::<NotCopy>(_1) -> bb1; // scope 0 at $DIR/custom_move_arg.rs:+3:9: +3:41
+                                           // mir::Constant
+                                           // + span: $DIR/custom_move_arg.rs:15:24: 15:30
+                                           // + literal: Const { ty: fn(NotCopy) {opaque::<NotCopy>}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+-         _3 = move _2;                    // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+-         _0 = opaque::<NotCopy>(_3) -> bb2; // scope 0 at $DIR/custom_move_arg.rs:+7:9: +7:35
++         _0 = opaque::<NotCopy>(_1) -> bb2; // scope 0 at $DIR/custom_move_arg.rs:+7:9: +7:35
+                                           // mir::Constant
+                                           // + span: $DIR/custom_move_arg.rs:19:24: 19:30
+                                           // + literal: Const { ty: fn(NotCopy) {opaque::<NotCopy>}, val: Value(<ZST>) }
+      }
+  
+      bb2: {
+          return;                          // scope 0 at $DIR/custom_move_arg.rs:+10:9: +10:17
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/custom_move_arg.rs b/tests/mir-opt/copy-prop/custom_move_arg.rs
new file mode 100644
index 000000000..4a591146e
--- /dev/null
+++ b/tests/mir-opt/copy-prop/custom_move_arg.rs
@@ -0,0 +1,32 @@
+// unit-test: CopyProp
+
+#![feature(custom_mir, core_intrinsics)]
+#![allow(unused_assignments)]
+extern crate core;
+use core::intrinsics::mir::*;
+
+struct NotCopy(bool);
+
+// EMIT_MIR custom_move_arg.f.CopyProp.diff
+#[custom_mir(dialect = "analysis", phase = "post-cleanup")]
+fn f(_1: NotCopy) {
+    mir!({
+        let _2 = _1;
+        Call(RET, bb1, opaque(Move(_1)))
+    }
+    bb1 = {
+        let _3 = Move(_2);
+        Call(RET, bb2, opaque(_3))
+    }
+    bb2 = {
+        Return()
+    })
+}
+
+#[inline(never)]
+fn opaque<T>(_t: T) {}
+
+fn main() {
+    f(NotCopy(true));
+    println!("hi");
+}
diff --git a/tests/mir-opt/copy-prop/cycle.main.CopyProp.diff b/tests/mir-opt/copy-prop/cycle.main.CopyProp.diff
new file mode 100644
index 000000000..3e61869e8
--- /dev/null
+++ b/tests/mir-opt/copy-prop/cycle.main.CopyProp.diff
@@ -0,0 +1,60 @@
+- // MIR for `main` before CopyProp
++ // MIR for `main` after CopyProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/cycle.rs:+0:11: +0:11
+      let mut _1: i32;                     // in scope 0 at $DIR/cycle.rs:+1:9: +1:14
+      let mut _4: i32;                     // in scope 0 at $DIR/cycle.rs:+4:9: +4:10
+      let _5: ();                          // in scope 0 at $DIR/cycle.rs:+6:5: +6:12
+      let mut _6: i32;                     // in scope 0 at $DIR/cycle.rs:+6:10: +6:11
+      scope 1 {
+          debug x => _1;                   // in scope 1 at $DIR/cycle.rs:+1:9: +1:14
+          let _2: i32;                     // in scope 1 at $DIR/cycle.rs:+2:9: +2:10
+          scope 2 {
+              debug y => _2;               // in scope 2 at $DIR/cycle.rs:+2:9: +2:10
+              let _3: i32;                 // in scope 2 at $DIR/cycle.rs:+3:9: +3:10
+              scope 3 {
+-                 debug z => _3;           // in scope 3 at $DIR/cycle.rs:+3:9: +3:10
++                 debug z => _2;           // in scope 3 at $DIR/cycle.rs:+3:9: +3:10
+              }
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/cycle.rs:+1:9: +1:14
+          _1 = val() -> bb1;               // scope 0 at $DIR/cycle.rs:+1:17: +1:22
+                                           // mir::Constant
+                                           // + span: $DIR/cycle.rs:9:17: 9:20
+                                           // + literal: Const { ty: fn() -> i32 {val}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+-         StorageLive(_2);                 // scope 1 at $DIR/cycle.rs:+2:9: +2:10
+          _2 = _1;                         // scope 1 at $DIR/cycle.rs:+2:13: +2:14
+-         StorageLive(_3);                 // scope 2 at $DIR/cycle.rs:+3:9: +3:10
+-         _3 = _2;                         // scope 2 at $DIR/cycle.rs:+3:13: +3:14
+-         StorageLive(_4);                 // scope 3 at $DIR/cycle.rs:+4:9: +4:10
+-         _4 = _3;                         // scope 3 at $DIR/cycle.rs:+4:9: +4:10
+-         _1 = move _4;                    // scope 3 at $DIR/cycle.rs:+4:5: +4:10
+-         StorageDead(_4);                 // scope 3 at $DIR/cycle.rs:+4:9: +4:10
++         _1 = _2;                         // scope 3 at $DIR/cycle.rs:+4:5: +4:10
+          StorageLive(_5);                 // scope 3 at $DIR/cycle.rs:+6:5: +6:12
+          StorageLive(_6);                 // scope 3 at $DIR/cycle.rs:+6:10: +6:11
+          _6 = _1;                         // scope 3 at $DIR/cycle.rs:+6:10: +6:11
+          _5 = std::mem::drop::<i32>(move _6) -> bb2; // scope 3 at $DIR/cycle.rs:+6:5: +6:12
+                                           // mir::Constant
+                                           // + span: $DIR/cycle.rs:14:5: 14:9
+                                           // + literal: Const { ty: fn(i32) {std::mem::drop::<i32>}, val: Value(<ZST>) }
+      }
+  
+      bb2: {
+          StorageDead(_6);                 // scope 3 at $DIR/cycle.rs:+6:11: +6:12
+          StorageDead(_5);                 // scope 3 at $DIR/cycle.rs:+6:12: +6:13
+          _0 = const ();                   // scope 0 at $DIR/cycle.rs:+0:11: +7:2
+-         StorageDead(_3);                 // scope 2 at $DIR/cycle.rs:+7:1: +7:2
+-         StorageDead(_2);                 // scope 1 at $DIR/cycle.rs:+7:1: +7:2
+          StorageDead(_1);                 // scope 0 at $DIR/cycle.rs:+7:1: +7:2
+          return;                          // scope 0 at $DIR/cycle.rs:+7:2: +7:2
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/cycle.rs b/tests/mir-opt/copy-prop/cycle.rs
new file mode 100644
index 000000000..b74c39726
--- /dev/null
+++ b/tests/mir-opt/copy-prop/cycle.rs
@@ -0,0 +1,15 @@
+//! Tests that cyclic assignments don't hang CopyProp, and result in reasonable code.
+// unit-test: CopyProp
+fn val() -> i32 {
+    1
+}
+
+// EMIT_MIR cycle.main.CopyProp.diff
+fn main() {
+    let mut x = val();
+    let y = x;
+    let z = y;
+    x = z;
+
+    drop(x);
+}
diff --git a/tests/mir-opt/copy-prop/dead_stores_79191.f.CopyProp.after.mir b/tests/mir-opt/copy-prop/dead_stores_79191.f.CopyProp.after.mir
new file mode 100644
index 000000000..d48b04e2d
--- /dev/null
+++ b/tests/mir-opt/copy-prop/dead_stores_79191.f.CopyProp.after.mir
@@ -0,0 +1,29 @@
+// MIR for `f` after CopyProp
+
+fn f(_1: usize) -> usize {
+    debug a => _1;                       // in scope 0 at $DIR/dead_stores_79191.rs:+0:6: +0:11
+    let mut _0: usize;                   // return place in scope 0 at $DIR/dead_stores_79191.rs:+0:23: +0:28
+    let _2: usize;                       // in scope 0 at $DIR/dead_stores_79191.rs:+1:9: +1:10
+    let mut _3: usize;                   // in scope 0 at $DIR/dead_stores_79191.rs:+3:9: +3:10
+    let mut _4: usize;                   // in scope 0 at $DIR/dead_stores_79191.rs:+4:8: +4:9
+    scope 1 {
+        debug b => _2;                   // in scope 1 at $DIR/dead_stores_79191.rs:+1:9: +1:10
+    }
+
+    bb0: {
+        _2 = _1;                         // scope 0 at $DIR/dead_stores_79191.rs:+1:13: +1:14
+        _1 = const 5_usize;              // scope 1 at $DIR/dead_stores_79191.rs:+2:5: +2:10
+        _1 = _2;                         // scope 1 at $DIR/dead_stores_79191.rs:+3:5: +3:10
+        StorageLive(_4);                 // scope 1 at $DIR/dead_stores_79191.rs:+4:8: +4:9
+        _4 = _1;                         // scope 1 at $DIR/dead_stores_79191.rs:+4:8: +4:9
+        _0 = id::<usize>(move _4) -> bb1; // scope 1 at $DIR/dead_stores_79191.rs:+4:5: +4:10
+                                         // mir::Constant
+                                         // + span: $DIR/dead_stores_79191.rs:12:5: 12:7
+                                         // + literal: Const { ty: fn(usize) -> usize {id::<usize>}, val: Value(<ZST>) }
+    }
+
+    bb1: {
+        StorageDead(_4);                 // scope 1 at $DIR/dead_stores_79191.rs:+4:9: +4:10
+        return;                          // scope 0 at $DIR/dead_stores_79191.rs:+5:2: +5:2
+    }
+}
diff --git a/tests/mir-opt/copy-prop/dead_stores_79191.rs b/tests/mir-opt/copy-prop/dead_stores_79191.rs
new file mode 100644
index 000000000..e3493b8b7
--- /dev/null
+++ b/tests/mir-opt/copy-prop/dead_stores_79191.rs
@@ -0,0 +1,17 @@
+// unit-test: CopyProp
+
+fn id<T>(x: T) -> T {
+    x
+}
+
+// EMIT_MIR dead_stores_79191.f.CopyProp.after.mir
+fn f(mut a: usize) -> usize {
+    let b = a;
+    a = 5;
+    a = b;
+    id(a)
+}
+
+fn main() {
+    f(0);
+}
diff --git a/tests/mir-opt/copy-prop/dead_stores_better.f.CopyProp.after.mir b/tests/mir-opt/copy-prop/dead_stores_better.f.CopyProp.after.mir
new file mode 100644
index 000000000..727791f50
--- /dev/null
+++ b/tests/mir-opt/copy-prop/dead_stores_better.f.CopyProp.after.mir
@@ -0,0 +1,29 @@
+// MIR for `f` after CopyProp
+
+fn f(_1: usize) -> usize {
+    debug a => _1;                       // in scope 0 at $DIR/dead_stores_better.rs:+0:10: +0:15
+    let mut _0: usize;                   // return place in scope 0 at $DIR/dead_stores_better.rs:+0:27: +0:32
+    let _2: usize;                       // in scope 0 at $DIR/dead_stores_better.rs:+1:9: +1:10
+    let mut _3: usize;                   // in scope 0 at $DIR/dead_stores_better.rs:+3:9: +3:10
+    let mut _4: usize;                   // in scope 0 at $DIR/dead_stores_better.rs:+4:8: +4:9
+    scope 1 {
+        debug b => _2;                   // in scope 1 at $DIR/dead_stores_better.rs:+1:9: +1:10
+    }
+
+    bb0: {
+        _2 = _1;                         // scope 0 at $DIR/dead_stores_better.rs:+1:13: +1:14
+        _1 = const 5_usize;              // scope 1 at $DIR/dead_stores_better.rs:+2:5: +2:10
+        _1 = _2;                         // scope 1 at $DIR/dead_stores_better.rs:+3:5: +3:10
+        StorageLive(_4);                 // scope 1 at $DIR/dead_stores_better.rs:+4:8: +4:9
+        _4 = _1;                         // scope 1 at $DIR/dead_stores_better.rs:+4:8: +4:9
+        _0 = id::<usize>(move _4) -> bb1; // scope 1 at $DIR/dead_stores_better.rs:+4:5: +4:10
+                                         // mir::Constant
+                                         // + span: $DIR/dead_stores_better.rs:16:5: 16:7
+                                         // + literal: Const { ty: fn(usize) -> usize {id::<usize>}, val: Value(<ZST>) }
+    }
+
+    bb1: {
+        StorageDead(_4);                 // scope 1 at $DIR/dead_stores_better.rs:+4:9: +4:10
+        return;                          // scope 0 at $DIR/dead_stores_better.rs:+5:2: +5:2
+    }
+}
diff --git a/tests/mir-opt/copy-prop/dead_stores_better.rs b/tests/mir-opt/copy-prop/dead_stores_better.rs
new file mode 100644
index 000000000..8465b3c98
--- /dev/null
+++ b/tests/mir-opt/copy-prop/dead_stores_better.rs
@@ -0,0 +1,21 @@
+// This is a copy of the `dead_stores_79191` test, except that we turn on DSE. This demonstrates
+// that that pass enables this one to do more optimizations.
+
+// unit-test: CopyProp
+// compile-flags: -Zmir-enable-passes=+DeadStoreElimination
+
+fn id<T>(x: T) -> T {
+    x
+}
+
+// EMIT_MIR dead_stores_better.f.CopyProp.after.mir
+pub fn f(mut a: usize) -> usize {
+    let b = a;
+    a = 5;
+    a = b;
+    id(a)
+}
+
+fn main() {
+    f(0);
+}
diff --git a/tests/mir-opt/copy-prop/issue_107511.main.CopyProp.diff b/tests/mir-opt/copy-prop/issue_107511.main.CopyProp.diff
new file mode 100644
index 000000000..97d0a01e0
--- /dev/null
+++ b/tests/mir-opt/copy-prop/issue_107511.main.CopyProp.diff
@@ -0,0 +1,138 @@
+- // MIR for `main` before CopyProp
++ // MIR for `main` after CopyProp
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/issue_107511.rs:+0:11: +0:11
+      let mut _1: i32;                     // in scope 0 at $DIR/issue_107511.rs:+1:9: +1:16
+      let mut _3: std::ops::Range<usize>;  // in scope 0 at $DIR/issue_107511.rs:+6:14: +6:24
+      let mut _4: std::ops::Range<usize>;  // in scope 0 at $DIR/issue_107511.rs:+6:14: +6:24
+      let mut _5: usize;                   // in scope 0 at $DIR/issue_107511.rs:+6:17: +6:24
+      let mut _6: &[i32];                  // in scope 0 at $DIR/issue_107511.rs:+6:17: +6:24
+      let mut _7: &[i32; 4];               // in scope 0 at $DIR/issue_107511.rs:+6:17: +6:24
+      let mut _9: ();                      // in scope 0 at $DIR/issue_107511.rs:+0:1: +9:2
+      let _10: ();                         // in scope 0 at $DIR/issue_107511.rs:+6:14: +6:24
+      let mut _11: std::option::Option<usize>; // in scope 0 at $DIR/issue_107511.rs:+6:14: +6:24
+      let mut _12: &mut std::ops::Range<usize>; // in scope 0 at $DIR/issue_107511.rs:+6:14: +6:24
+      let mut _13: &mut std::ops::Range<usize>; // in scope 0 at $DIR/issue_107511.rs:+6:14: +6:24
+      let mut _14: isize;                  // in scope 0 at $DIR/issue_107511.rs:+6:5: +8:6
+      let mut _15: !;                      // in scope 0 at $DIR/issue_107511.rs:+6:5: +8:6
+      let mut _17: i32;                    // in scope 0 at $DIR/issue_107511.rs:+7:16: +7:20
+      let _18: usize;                      // in scope 0 at $DIR/issue_107511.rs:+7:18: +7:19
+      let mut _19: usize;                  // in scope 0 at $DIR/issue_107511.rs:+7:16: +7:20
+      let mut _20: bool;                   // in scope 0 at $DIR/issue_107511.rs:+7:16: +7:20
+      scope 1 {
+          debug sum => _1;                 // in scope 1 at $DIR/issue_107511.rs:+1:9: +1:16
+          let _2: [i32; 4];                // in scope 1 at $DIR/issue_107511.rs:+2:9: +2:10
+          scope 2 {
+              debug a => _2;               // in scope 2 at $DIR/issue_107511.rs:+2:9: +2:10
+              let mut _8: std::ops::Range<usize>; // in scope 2 at $DIR/issue_107511.rs:+6:14: +6:24
+              scope 3 {
+                  debug iter => _8;        // in scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+                  let _16: usize;          // in scope 3 at $DIR/issue_107511.rs:+6:9: +6:10
+                  scope 4 {
+                      debug i => _16;      // in scope 4 at $DIR/issue_107511.rs:+6:9: +6:10
+                  }
+              }
+          }
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/issue_107511.rs:+1:9: +1:16
+          _1 = const 0_i32;                // scope 0 at $DIR/issue_107511.rs:+1:19: +1:20
+          StorageLive(_2);                 // scope 1 at $DIR/issue_107511.rs:+2:9: +2:10
+          _2 = [const 0_i32, const 10_i32, const 20_i32, const 30_i32]; // scope 1 at $DIR/issue_107511.rs:+2:13: +2:28
+          StorageLive(_3);                 // scope 2 at $DIR/issue_107511.rs:+6:14: +6:24
+          StorageLive(_4);                 // scope 2 at $DIR/issue_107511.rs:+6:14: +6:24
+          StorageLive(_5);                 // scope 2 at $DIR/issue_107511.rs:+6:17: +6:24
+          StorageLive(_6);                 // scope 2 at $DIR/issue_107511.rs:+6:17: +6:24
+          StorageLive(_7);                 // scope 2 at $DIR/issue_107511.rs:+6:17: +6:24
+          _7 = &_2;                        // scope 2 at $DIR/issue_107511.rs:+6:17: +6:24
+          _6 = move _7 as &[i32] (Pointer(Unsize)); // scope 2 at $DIR/issue_107511.rs:+6:17: +6:24
+          StorageDead(_7);                 // scope 2 at $DIR/issue_107511.rs:+6:17: +6:18
+          _5 = core::slice::<impl [i32]>::len(move _6) -> bb1; // scope 2 at $DIR/issue_107511.rs:+6:17: +6:24
+                                           // mir::Constant
+                                           // + span: $DIR/issue_107511.rs:10:19: 10:22
+                                           // + literal: Const { ty: for<'a> fn(&'a [i32]) -> usize {core::slice::<impl [i32]>::len}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_6);                 // scope 2 at $DIR/issue_107511.rs:+6:23: +6:24
+          _4 = std::ops::Range::<usize> { start: const 0_usize, end: move _5 }; // scope 2 at $DIR/issue_107511.rs:+6:14: +6:24
+          StorageDead(_5);                 // scope 2 at $DIR/issue_107511.rs:+6:23: +6:24
+          _3 = <std::ops::Range<usize> as IntoIterator>::into_iter(move _4) -> bb2; // scope 2 at $DIR/issue_107511.rs:+6:14: +6:24
+                                           // mir::Constant
+                                           // + span: $DIR/issue_107511.rs:10:14: 10:24
+                                           // + literal: Const { ty: fn(std::ops::Range<usize>) -> <std::ops::Range<usize> as IntoIterator>::IntoIter {<std::ops::Range<usize> as IntoIterator>::into_iter}, val: Value(<ZST>) }
+      }
+  
+      bb2: {
+          StorageDead(_4);                 // scope 2 at $DIR/issue_107511.rs:+6:23: +6:24
+          StorageLive(_8);                 // scope 2 at $DIR/issue_107511.rs:+6:14: +6:24
+          _8 = move _3;                    // scope 2 at $DIR/issue_107511.rs:+6:14: +6:24
+          goto -> bb3;                     // scope 3 at $DIR/issue_107511.rs:+6:5: +8:6
+      }
+  
+      bb3: {
+-         StorageLive(_10);                // scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+          StorageLive(_11);                // scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+          StorageLive(_12);                // scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+          StorageLive(_13);                // scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+          _13 = &mut _8;                   // scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+          _12 = &mut (*_13);               // scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+          _11 = <std::ops::Range<usize> as Iterator>::next(move _12) -> bb4; // scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+                                           // mir::Constant
+                                           // + span: $DIR/issue_107511.rs:10:14: 10:24
+                                           // + literal: Const { ty: for<'a> fn(&'a mut std::ops::Range<usize>) -> Option<<std::ops::Range<usize> as Iterator>::Item> {<std::ops::Range<usize> as Iterator>::next}, val: Value(<ZST>) }
+      }
+  
+      bb4: {
+          StorageDead(_12);                // scope 3 at $DIR/issue_107511.rs:+6:23: +6:24
+          _14 = discriminant(_11);         // scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+          switchInt(move _14) -> [0: bb7, 1: bb5, otherwise: bb6]; // scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+      }
+  
+      bb5: {
+-         StorageLive(_16);                // scope 3 at $DIR/issue_107511.rs:+6:9: +6:10
+          _16 = ((_11 as Some).0: usize);  // scope 3 at $DIR/issue_107511.rs:+6:9: +6:10
+          StorageLive(_17);                // scope 4 at $DIR/issue_107511.rs:+7:16: +7:20
+-         StorageLive(_18);                // scope 4 at $DIR/issue_107511.rs:+7:18: +7:19
+-         _18 = _16;                       // scope 4 at $DIR/issue_107511.rs:+7:18: +7:19
+          _19 = Len(_2);                   // scope 4 at $DIR/issue_107511.rs:+7:16: +7:20
+-         _20 = Lt(_18, _19);              // scope 4 at $DIR/issue_107511.rs:+7:16: +7:20
+-         assert(move _20, "index out of bounds: the length is {} but the index is {}", move _19, _18) -> bb8; // scope 4 at $DIR/issue_107511.rs:+7:16: +7:20
++         _20 = Lt(_16, _19);              // scope 4 at $DIR/issue_107511.rs:+7:16: +7:20
++         assert(move _20, "index out of bounds: the length is {} but the index is {}", move _19, _16) -> bb8; // scope 4 at $DIR/issue_107511.rs:+7:16: +7:20
+      }
+  
+      bb6: {
+          unreachable;                     // scope 3 at $DIR/issue_107511.rs:+6:14: +6:24
+      }
+  
+      bb7: {
+          _0 = const ();                   // scope 3 at $DIR/issue_107511.rs:+6:5: +8:6
+          StorageDead(_13);                // scope 3 at $DIR/issue_107511.rs:+8:5: +8:6
+          StorageDead(_11);                // scope 3 at $DIR/issue_107511.rs:+8:5: +8:6
+-         StorageDead(_10);                // scope 3 at $DIR/issue_107511.rs:+8:5: +8:6
+          StorageDead(_8);                 // scope 2 at $DIR/issue_107511.rs:+8:5: +8:6
+          StorageDead(_3);                 // scope 2 at $DIR/issue_107511.rs:+8:5: +8:6
+          StorageDead(_2);                 // scope 1 at $DIR/issue_107511.rs:+9:1: +9:2
+          StorageDead(_1);                 // scope 0 at $DIR/issue_107511.rs:+9:1: +9:2
+          return;                          // scope 0 at $DIR/issue_107511.rs:+9:2: +9:2
+      }
+  
+      bb8: {
+-         _17 = _2[_18];                   // scope 4 at $DIR/issue_107511.rs:+7:16: +7:20
++         _17 = _2[_16];                   // scope 4 at $DIR/issue_107511.rs:+7:16: +7:20
+          _1 = Add(_1, move _17);          // scope 4 at $DIR/issue_107511.rs:+7:9: +7:20
+          StorageDead(_17);                // scope 4 at $DIR/issue_107511.rs:+7:19: +7:20
+-         StorageDead(_18);                // scope 4 at $DIR/issue_107511.rs:+7:20: +7:21
+-         _10 = const ();                  // scope 4 at $DIR/issue_107511.rs:+6:25: +8:6
+-         StorageDead(_16);                // scope 3 at $DIR/issue_107511.rs:+8:5: +8:6
+          StorageDead(_13);                // scope 3 at $DIR/issue_107511.rs:+8:5: +8:6
+          StorageDead(_11);                // scope 3 at $DIR/issue_107511.rs:+8:5: +8:6
+-         StorageDead(_10);                // scope 3 at $DIR/issue_107511.rs:+8:5: +8:6
+-         _9 = const ();                   // scope 3 at $DIR/issue_107511.rs:+6:5: +8:6
+          goto -> bb3;                     // scope 3 at $DIR/issue_107511.rs:+6:5: +8:6
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/issue_107511.rs b/tests/mir-opt/copy-prop/issue_107511.rs
new file mode 100644
index 000000000..d593f2872
--- /dev/null
+++ b/tests/mir-opt/copy-prop/issue_107511.rs
@@ -0,0 +1,13 @@
+// unit-test: CopyProp
+
+// EMIT_MIR issue_107511.main.CopyProp.diff
+fn main() {
+    let mut sum = 0;
+    let a = [0, 10, 20, 30];
+
+    // `i` is assigned in a loop. Only removing its `StorageDead` would mean that
+    // execution sees repeated `StorageLive`. This would be UB.
+    for i in 0..a.len() {
+        sum += a[i];
+    }
+}
diff --git a/tests/mir-opt/copy-prop/move_arg.f.CopyProp.diff b/tests/mir-opt/copy-prop/move_arg.f.CopyProp.diff
new file mode 100644
index 000000000..d76bf1cfe
--- /dev/null
+++ b/tests/mir-opt/copy-prop/move_arg.f.CopyProp.diff
@@ -0,0 +1,40 @@
+- // MIR for `f` before CopyProp
++ // MIR for `f` after CopyProp
+  
+  fn f(_1: T) -> () {
+      debug a => _1;                       // in scope 0 at $DIR/move_arg.rs:+0:19: +0:20
+      let mut _0: ();                      // return place in scope 0 at $DIR/move_arg.rs:+0:25: +0:25
+      let _2: T;                           // in scope 0 at $DIR/move_arg.rs:+1:9: +1:10
+      let _3: ();                          // in scope 0 at $DIR/move_arg.rs:+2:5: +2:12
+      let mut _4: T;                       // in scope 0 at $DIR/move_arg.rs:+2:7: +2:8
+      let mut _5: T;                       // in scope 0 at $DIR/move_arg.rs:+2:10: +2:11
+      scope 1 {
+-         debug b => _2;                   // in scope 1 at $DIR/move_arg.rs:+1:9: +1:10
++         debug b => _1;                   // in scope 1 at $DIR/move_arg.rs:+1:9: +1:10
+      }
+  
+      bb0: {
+-         StorageLive(_2);                 // scope 0 at $DIR/move_arg.rs:+1:9: +1:10
+-         _2 = _1;                         // scope 0 at $DIR/move_arg.rs:+1:13: +1:14
+          StorageLive(_3);                 // scope 1 at $DIR/move_arg.rs:+2:5: +2:12
+-         StorageLive(_4);                 // scope 1 at $DIR/move_arg.rs:+2:7: +2:8
+-         _4 = _1;                         // scope 1 at $DIR/move_arg.rs:+2:7: +2:8
+-         StorageLive(_5);                 // scope 1 at $DIR/move_arg.rs:+2:10: +2:11
+-         _5 = _2;                         // scope 1 at $DIR/move_arg.rs:+2:10: +2:11
+-         _3 = g::<T>(move _4, move _5) -> bb1; // scope 1 at $DIR/move_arg.rs:+2:5: +2:12
++         _3 = g::<T>(_1, _1) -> bb1;      // scope 1 at $DIR/move_arg.rs:+2:5: +2:12
+                                           // mir::Constant
+                                           // + span: $DIR/move_arg.rs:7:5: 7:6
+                                           // + literal: Const { ty: fn(T, T) {g::<T>}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+-         StorageDead(_5);                 // scope 1 at $DIR/move_arg.rs:+2:11: +2:12
+-         StorageDead(_4);                 // scope 1 at $DIR/move_arg.rs:+2:11: +2:12
+          StorageDead(_3);                 // scope 1 at $DIR/move_arg.rs:+2:12: +2:13
+          _0 = const ();                   // scope 0 at $DIR/move_arg.rs:+0:25: +3:2
+-         StorageDead(_2);                 // scope 0 at $DIR/move_arg.rs:+3:1: +3:2
+          return;                          // scope 0 at $DIR/move_arg.rs:+3:2: +3:2
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/move_arg.rs b/tests/mir-opt/copy-prop/move_arg.rs
new file mode 100644
index 000000000..40ae1d8f4
--- /dev/null
+++ b/tests/mir-opt/copy-prop/move_arg.rs
@@ -0,0 +1,15 @@
+// Test that we do not move multiple times from the same local.
+// unit-test: CopyProp
+
+// EMIT_MIR move_arg.f.CopyProp.diff
+pub fn f<T: Copy>(a: T) {
+    let b = a;
+    g(a, b);
+}
+
+#[inline(never)]
+pub fn g<T: Copy>(_: T, _: T) {}
+
+fn main() {
+    f(5)
+}
diff --git a/tests/mir-opt/copy-prop/move_projection.f.CopyProp.diff b/tests/mir-opt/copy-prop/move_projection.f.CopyProp.diff
new file mode 100644
index 000000000..02308beb8
--- /dev/null
+++ b/tests/mir-opt/copy-prop/move_projection.f.CopyProp.diff
@@ -0,0 +1,31 @@
+- // MIR for `f` before CopyProp
++ // MIR for `f` after CopyProp
+  
+  fn f(_1: Foo) -> bool {
+      let mut _0: bool;                    // return place in scope 0 at $DIR/move_projection.rs:+0:17: +0:21
+      let mut _2: Foo;                     // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+      let mut _3: u8;                      // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+  
+      bb0: {
+-         _2 = _1;                         // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+-         _3 = move (_2.0: u8);            // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+-         _0 = opaque::<Foo>(move _1) -> bb1; // scope 0 at $DIR/move_projection.rs:+6:13: +6:44
++         _3 = (_1.0: u8);                 // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
++         _0 = opaque::<Foo>(_1) -> bb1;   // scope 0 at $DIR/move_projection.rs:+6:13: +6:44
+                                           // mir::Constant
+                                           // + span: $DIR/move_projection.rs:19:28: 19:34
+                                           // + literal: Const { ty: fn(Foo) -> bool {opaque::<Foo>}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          _0 = opaque::<u8>(move _3) -> bb2; // scope 0 at $DIR/move_projection.rs:+9:13: +9:44
+                                           // mir::Constant
+                                           // + span: $DIR/move_projection.rs:22:28: 22:34
+                                           // + literal: Const { ty: fn(u8) -> bool {opaque::<u8>}, val: Value(<ZST>) }
+      }
+  
+      bb2: {
+          return;                          // scope 0 at $DIR/move_projection.rs:+12:13: +12:21
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/move_projection.rs b/tests/mir-opt/copy-prop/move_projection.rs
new file mode 100644
index 000000000..2a1bbae99
--- /dev/null
+++ b/tests/mir-opt/copy-prop/move_projection.rs
@@ -0,0 +1,34 @@
+// unit-test: CopyProp
+
+#![feature(custom_mir, core_intrinsics)]
+#![allow(unused_assignments)]
+extern crate core;
+use core::intrinsics::mir::*;
+
+fn opaque(_: impl Sized) -> bool { true }
+
+struct Foo(u8);
+
+#[custom_mir(dialect = "analysis", phase = "post-cleanup")]
+fn f(a: Foo) -> bool {
+    mir!(
+        {
+            let b = a;
+            // This is a move out of a copy, so must become a copy of `a.0`.
+            let c = Move(b.0);
+            Call(RET, bb1, opaque(Move(a)))
+        }
+        bb1 = {
+            Call(RET, ret, opaque(Move(c)))
+        }
+        ret = {
+            Return()
+        }
+    )
+}
+
+fn main() {
+    assert!(f(Foo(0)));
+}
+
+// EMIT_MIR move_projection.f.CopyProp.diff
diff --git a/tests/mir-opt/copy-prop/mutate_through_pointer.f.CopyProp.diff b/tests/mir-opt/copy-prop/mutate_through_pointer.f.CopyProp.diff
new file mode 100644
index 000000000..61fdd6f8c
--- /dev/null
+++ b/tests/mir-opt/copy-prop/mutate_through_pointer.f.CopyProp.diff
@@ -0,0 +1,19 @@
+- // MIR for `f` before CopyProp
++ // MIR for `f` after CopyProp
+  
+  fn f(_1: bool) -> bool {
+      let mut _0: bool;                    // return place in scope 0 at $DIR/mutate_through_pointer.rs:+0:18: +0:22
+      let mut _2: bool;                    // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+      let mut _3: *const bool;             // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+      let mut _4: *mut bool;               // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+  
+      bb0: {
+          _2 = _1;                         // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+          _3 = &raw const _2;              // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+          _4 = &raw mut (*_3);             // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+          (*_4) = const false;             // scope 0 at $DIR/mutate_through_pointer.rs:+5:9: +5:20
+          _0 = _1;                         // scope 0 at $DIR/mutate_through_pointer.rs:+6:9: +6:16
+          return;                          // scope 0 at $DIR/mutate_through_pointer.rs:+7:9: +7:17
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/mutate_through_pointer.rs b/tests/mir-opt/copy-prop/mutate_through_pointer.rs
new file mode 100644
index 000000000..da142e339
--- /dev/null
+++ b/tests/mir-opt/copy-prop/mutate_through_pointer.rs
@@ -0,0 +1,32 @@
+// This attempts to mutate `a` via a pointer derived from `addr_of!(a)`. That is UB
+// according to Miri. However, the decision to make this UB - and to allow
+// rustc to rely on that fact for the purpose of optimizations - has not been
+// finalized.
+//
+// As such, we include this test to ensure that copy prop does not rely on that
+// fact. Specifically, if `addr_of!(a)` could not be used to modify a, it would
+// be correct for CopyProp to replace all occurrences of `a` with `c` - but that
+// would cause `f(true)` to output `false` instead of `true`.
+
+#![feature(custom_mir, core_intrinsics)]
+#![allow(unused_assignments)]
+extern crate core;
+use core::intrinsics::mir::*;
+
+#[custom_mir(dialect = "analysis", phase = "post-cleanup")]
+fn f(c: bool) -> bool {
+    mir!({
+        let a = c;
+        let p = core::ptr::addr_of!(a);
+        let p2 = core::ptr::addr_of_mut!(*p);
+        *p2 = false;
+        RET = c;
+        Return()
+    })
+}
+
+fn main() {
+    assert_eq!(true, f(true));
+}
+
+// EMIT_MIR mutate_through_pointer.f.CopyProp.diff
diff --git a/tests/mir-opt/copy-prop/non_dominate.f.CopyProp.diff b/tests/mir-opt/copy-prop/non_dominate.f.CopyProp.diff
new file mode 100644
index 000000000..9760fd374
--- /dev/null
+++ b/tests/mir-opt/copy-prop/non_dominate.f.CopyProp.diff
@@ -0,0 +1,29 @@
+- // MIR for `f` before CopyProp
++ // MIR for `f` after CopyProp
+  
+  fn f(_1: bool) -> bool {
+      let mut _0: bool;                    // return place in scope 0 at $DIR/non_dominate.rs:+0:18: +0:22
+      let mut _2: bool;                    // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+      let mut _3: bool;                    // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+  
+      bb0: {
+          goto -> bb1;                     // scope 0 at $DIR/non_dominate.rs:+4:11: +4:20
+      }
+  
+      bb1: {
+          _3 = _1;                         // scope 0 at $DIR/non_dominate.rs:+5:17: +5:22
+          switchInt(_3) -> [0: bb3, otherwise: bb2]; // scope 0 at $DIR/non_dominate.rs:+5:24: +5:58
+      }
+  
+      bb2: {
+          _2 = _3;                         // scope 0 at $DIR/non_dominate.rs:+8:17: +8:22
+          _1 = const false;                // scope 0 at $DIR/non_dominate.rs:+8:24: +8:33
+          goto -> bb1;                     // scope 0 at $DIR/non_dominate.rs:+8:35: +8:44
+      }
+  
+      bb3: {
+          _0 = _2;                         // scope 0 at $DIR/non_dominate.rs:+9:17: +9:24
+          return;                          // scope 0 at $DIR/non_dominate.rs:+9:26: +9:34
+      }
+  }
+  
diff --git a/tests/mir-opt/copy-prop/non_dominate.rs b/tests/mir-opt/copy-prop/non_dominate.rs
new file mode 100644
index 000000000..c0ea838e1
--- /dev/null
+++ b/tests/mir-opt/copy-prop/non_dominate.rs
@@ -0,0 +1,26 @@
+// unit-test: CopyProp
+
+#![feature(custom_mir, core_intrinsics)]
+#![allow(unused_assignments)]
+extern crate core;
+use core::intrinsics::mir::*;
+
+#[custom_mir(dialect = "analysis", phase = "post-cleanup")]
+fn f(c: bool) -> bool {
+    mir!(
+        let a: bool;
+        let b: bool;
+        { Goto(bb1) }
+        bb1 = { b = c; match b { false => bb3, _ => bb2 }}
+        // This assignment to `a` does not dominate the use in `bb3`.
+        // It should not be replaced by `b`.
+        bb2 = { a = b; c = false; Goto(bb1) }
+        bb3 = { RET = a; Return() }
+    )
+}
+
+fn main() {
+    assert_eq!(true, f(true));
+}
+
+// EMIT_MIR non_dominate.f.CopyProp.diff
diff --git a/tests/mir-opt/dataflow-const-prop/checked.main.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/checked.main.DataflowConstProp.diff
index a4ebd0c8c..944afed8f 100644
--- a/tests/mir-opt/dataflow-const-prop/checked.main.DataflowConstProp.diff
+++ b/tests/mir-opt/dataflow-const-prop/checked.main.DataflowConstProp.diff
@@ -61,7 +61,7 @@
 -         assert(!move (_10.1: bool), "attempt to compute `{} + {}`, which would overflow", move _9, const 1_i32) -> bb2; // scope 4 at $DIR/checked.rs:+6:13: +6:18
 +         _9 = const i32::MAX;             // scope 4 at $DIR/checked.rs:+6:13: +6:14
 +         _10 = CheckedAdd(const i32::MAX, const 1_i32); // scope 4 at $DIR/checked.rs:+6:13: +6:18
-+         assert(!move (_10.1: bool), "attempt to compute `{} + {}`, which would overflow", const i32::MAX, const 1_i32) -> bb2; // scope 4 at $DIR/checked.rs:+6:13: +6:18
++         assert(!const true, "attempt to compute `{} + {}`, which would overflow", const i32::MAX, const 1_i32) -> bb2; // scope 4 at $DIR/checked.rs:+6:13: +6:18
       }
   
       bb2: {
diff --git a/tests/mir-opt/dataflow-const-prop/enum.multiple.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/enum.multiple.DataflowConstProp.diff
new file mode 100644
index 000000000..c4002d65e
--- /dev/null
+++ b/tests/mir-opt/dataflow-const-prop/enum.multiple.DataflowConstProp.diff
@@ -0,0 +1,82 @@
+- // MIR for `multiple` before DataflowConstProp
++ // MIR for `multiple` after DataflowConstProp
+  
+  fn multiple(_1: bool, _2: u8) -> () {
+      debug x => _1;                       // in scope 0 at $DIR/enum.rs:+0:13: +0:14
+      debug i => _2;                       // in scope 0 at $DIR/enum.rs:+0:22: +0:23
+      let mut _0: ();                      // return place in scope 0 at $DIR/enum.rs:+0:29: +0:29
+      let _3: std::option::Option<u8>;     // in scope 0 at $DIR/enum.rs:+1:9: +1:10
+      let mut _4: bool;                    // in scope 0 at $DIR/enum.rs:+1:16: +1:17
+      let mut _5: u8;                      // in scope 0 at $DIR/enum.rs:+2:14: +2:15
+      let mut _7: isize;                   // in scope 0 at $DIR/enum.rs:+9:23: +9:30
+      scope 1 {
+          debug e => _3;                   // in scope 1 at $DIR/enum.rs:+1:9: +1:10
+          let _6: u8;                      // in scope 1 at $DIR/enum.rs:+9:9: +9:10
+          let _8: u8;                      // in scope 1 at $DIR/enum.rs:+9:28: +9:29
+          scope 2 {
+              debug x => _6;               // in scope 2 at $DIR/enum.rs:+9:9: +9:10
+              let _9: u8;                  // in scope 2 at $DIR/enum.rs:+11:9: +11:10
+              scope 4 {
+                  debug y => _9;           // in scope 4 at $DIR/enum.rs:+11:9: +11:10
+              }
+          }
+          scope 3 {
+              debug i => _8;               // in scope 3 at $DIR/enum.rs:+9:28: +9:29
+          }
+      }
+  
+      bb0: {
+          StorageLive(_3);                 // scope 0 at $DIR/enum.rs:+1:9: +1:10
+          StorageLive(_4);                 // scope 0 at $DIR/enum.rs:+1:16: +1:17
+          _4 = _1;                         // scope 0 at $DIR/enum.rs:+1:16: +1:17
+          switchInt(move _4) -> [0: bb2, otherwise: bb1]; // scope 0 at $DIR/enum.rs:+1:16: +1:17
+      }
+  
+      bb1: {
+          StorageLive(_5);                 // scope 0 at $DIR/enum.rs:+2:14: +2:15
+          _5 = _2;                         // scope 0 at $DIR/enum.rs:+2:14: +2:15
+          _3 = Option::<u8>::Some(move _5); // scope 0 at $DIR/enum.rs:+2:9: +2:16
+          StorageDead(_5);                 // scope 0 at $DIR/enum.rs:+2:15: +2:16
+          goto -> bb3;                     // scope 0 at $DIR/enum.rs:+1:13: +5:6
+      }
+  
+      bb2: {
+          _3 = Option::<u8>::None;         // scope 0 at $DIR/enum.rs:+4:9: +4:13
+          goto -> bb3;                     // scope 0 at $DIR/enum.rs:+1:13: +5:6
+      }
+  
+      bb3: {
+          StorageDead(_4);                 // scope 0 at $DIR/enum.rs:+5:5: +5:6
+          StorageLive(_6);                 // scope 1 at $DIR/enum.rs:+9:9: +9:10
+          _7 = discriminant(_3);           // scope 1 at $DIR/enum.rs:+9:19: +9:20
+          switchInt(move _7) -> [0: bb4, 1: bb6, otherwise: bb5]; // scope 1 at $DIR/enum.rs:+9:13: +9:20
+      }
+  
+      bb4: {
+          _6 = const 0_u8;                 // scope 1 at $DIR/enum.rs:+9:45: +9:46
+          goto -> bb7;                     // scope 1 at $DIR/enum.rs:+9:45: +9:46
+      }
+  
+      bb5: {
+          unreachable;                     // scope 1 at $DIR/enum.rs:+9:19: +9:20
+      }
+  
+      bb6: {
+          StorageLive(_8);                 // scope 1 at $DIR/enum.rs:+9:28: +9:29
+          _8 = ((_3 as Some).0: u8);       // scope 1 at $DIR/enum.rs:+9:28: +9:29
+          _6 = _8;                         // scope 3 at $DIR/enum.rs:+9:34: +9:35
+          StorageDead(_8);                 // scope 1 at $DIR/enum.rs:+9:34: +9:35
+          goto -> bb7;                     // scope 1 at $DIR/enum.rs:+9:34: +9:35
+      }
+  
+      bb7: {
+          StorageLive(_9);                 // scope 2 at $DIR/enum.rs:+11:9: +11:10
+          _9 = _6;                         // scope 2 at $DIR/enum.rs:+11:13: +11:14
+          _0 = const ();                   // scope 0 at $DIR/enum.rs:+0:29: +12:2
+          StorageDead(_9);                 // scope 2 at $DIR/enum.rs:+12:1: +12:2
+          StorageDead(_6);                 // scope 1 at $DIR/enum.rs:+12:1: +12:2
+          StorageDead(_3);                 // scope 0 at $DIR/enum.rs:+12:1: +12:2
+          return;                          // scope 0 at $DIR/enum.rs:+12:2: +12:2
+      }
+  }
+  
diff --git a/tests/mir-opt/dataflow-const-prop/enum.mutate_discriminant.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/enum.mutate_discriminant.DataflowConstProp.diff
new file mode 100644
index 000000000..038e6c6bd
--- /dev/null
+++ b/tests/mir-opt/dataflow-const-prop/enum.mutate_discriminant.DataflowConstProp.diff
@@ -0,0 +1,26 @@
+- // MIR for `mutate_discriminant` before DataflowConstProp
++ // MIR for `mutate_discriminant` after DataflowConstProp
+  
+  fn mutate_discriminant() -> u8 {
+      let mut _0: u8;                      // return place in scope 0 at $DIR/enum.rs:+0:29: +0:31
+      let mut _1: std::option::Option<NonZeroUsize>; // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+      let mut _2: isize;                   // in scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+  
+      bb0: {
+          discriminant(_1) = 1;            // scope 0 at $DIR/enum.rs:+4:13: +4:34
+          (((_1 as variant#1).0: NonZeroUsize).0: usize) = const 0_usize; // scope 0 at $DIR/enum.rs:+6:13: +6:64
+          _2 = discriminant(_1);           // scope 0 at $SRC_DIR/core/src/intrinsics/mir.rs:LL:COL
+          switchInt(_2) -> [0: bb1, otherwise: bb2]; // scope 0 at $DIR/enum.rs:+9:13: +12:14
+      }
+  
+      bb1: {
+          _0 = const 1_u8;                 // scope 0 at $DIR/enum.rs:+15:13: +15:20
+          return;                          // scope 0 at $DIR/enum.rs:+16:13: +16:21
+      }
+  
+      bb2: {
+          _0 = const 2_u8;                 // scope 0 at $DIR/enum.rs:+19:13: +19:20
+          unreachable;                     // scope 0 at $DIR/enum.rs:+20:13: +20:26
+      }
+  }
+  
diff --git a/tests/mir-opt/dataflow-const-prop/enum.rs b/tests/mir-opt/dataflow-const-prop/enum.rs
index 13288577d..79a20d7ef 100644
--- a/tests/mir-opt/dataflow-const-prop/enum.rs
+++ b/tests/mir-opt/dataflow-const-prop/enum.rs
@@ -1,13 +1,68 @@
 // unit-test: DataflowConstProp
 
-// Not trackable, because variants could be aliased.
+#![feature(custom_mir, core_intrinsics, rustc_attrs)]
+
+use std::intrinsics::mir::*;
+
 enum E {
     V1(i32),
     V2(i32)
 }
 
-// EMIT_MIR enum.main.DataflowConstProp.diff
-fn main() {
+// EMIT_MIR enum.simple.DataflowConstProp.diff
+fn simple() {
     let e = E::V1(0);
     let x = match e { E::V1(x) => x, E::V2(x) => x };
 }
+
+#[rustc_layout_scalar_valid_range_start(1)]
+#[rustc_nonnull_optimization_guaranteed]
+struct NonZeroUsize(usize);
+
+// EMIT_MIR enum.mutate_discriminant.DataflowConstProp.diff
+#[custom_mir(dialect = "runtime", phase = "post-cleanup")]
+fn mutate_discriminant() -> u8 {
+    mir!(
+        let x: Option<NonZeroUsize>;
+        {
+            SetDiscriminant(x, 1);
+            // This assignment overwrites the niche in which the discriminant is stored.
+            place!(Field(Field(Variant(x, 1), 0), 0)) = 0_usize;
+            // So we cannot know the value of this discriminant.
+            let a = Discriminant(x);
+            match a {
+                0 => bb1,
+                _ => bad,
+            }
+        }
+        bb1 = {
+            RET = 1;
+            Return()
+        }
+        bad = {
+            RET = 2;
+            Unreachable()
+        }
+    )
+}
+
+// EMIT_MIR enum.multiple.DataflowConstProp.diff
+fn multiple(x: bool, i: u8) {
+    let e = if x {
+        Some(i)
+    } else {
+        None
+    };
+    // The dataflow state must have:
+    //   discriminant(e) => Top
+    //   (e as Some).0 => Top
+    let x = match e { Some(i) => i, None => 0 };
+    // Therefore, `x` should be `Top` here, and no replacement shall happen.
+    let y = x;
+}
+
+fn main() {
+    simple();
+    mutate_discriminant();
+    multiple(false, 5);
+}
diff --git a/tests/mir-opt/dataflow-const-prop/enum.main.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/enum.simple.DataflowConstProp.diff
index fce18fae4..22bdc35d6 100644
--- a/tests/mir-opt/dataflow-const-prop/enum.main.DataflowConstProp.diff
+++ b/tests/mir-opt/dataflow-const-prop/enum.simple.DataflowConstProp.diff
@@ -1,8 +1,8 @@
-- // MIR for `main` before DataflowConstProp
-+ // MIR for `main` after DataflowConstProp
+- // MIR for `simple` before DataflowConstProp
++ // MIR for `simple` after DataflowConstProp
   
-  fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/enum.rs:+0:11: +0:11
+  fn simple() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/enum.rs:+0:13: +0:13
       let _1: E;                           // in scope 0 at $DIR/enum.rs:+1:9: +1:10
       let mut _3: isize;                   // in scope 0 at $DIR/enum.rs:+2:23: +2:31
       scope 1 {
@@ -23,12 +23,12 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/enum.rs:+1:9: +1:10
-          Deinit(_1);                      // scope 0 at $DIR/enum.rs:+1:13: +1:21
-          ((_1 as V1).0: i32) = const 0_i32; // scope 0 at $DIR/enum.rs:+1:13: +1:21
-          discriminant(_1) = 0;            // scope 0 at $DIR/enum.rs:+1:13: +1:21
+          _1 = E::V1(const 0_i32);         // scope 0 at $DIR/enum.rs:+1:13: +1:21
           StorageLive(_2);                 // scope 1 at $DIR/enum.rs:+2:9: +2:10
-          _3 = discriminant(_1);           // scope 1 at $DIR/enum.rs:+2:19: +2:20
-          switchInt(move _3) -> [0: bb3, 1: bb1, otherwise: bb2]; // scope 1 at $DIR/enum.rs:+2:13: +2:20
+-         _3 = discriminant(_1);           // scope 1 at $DIR/enum.rs:+2:19: +2:20
+-         switchInt(move _3) -> [0: bb3, 1: bb1, otherwise: bb2]; // scope 1 at $DIR/enum.rs:+2:13: +2:20
++         _3 = const 0_isize;              // scope 1 at $DIR/enum.rs:+2:19: +2:20
++         switchInt(const 0_isize) -> [0: bb3, 1: bb1, otherwise: bb2]; // scope 1 at $DIR/enum.rs:+2:13: +2:20
       }
   
       bb1: {
@@ -45,14 +45,16 @@
   
       bb3: {
           StorageLive(_4);                 // scope 1 at $DIR/enum.rs:+2:29: +2:30
-          _4 = ((_1 as V1).0: i32);        // scope 1 at $DIR/enum.rs:+2:29: +2:30
-          _2 = _4;                         // scope 3 at $DIR/enum.rs:+2:35: +2:36
+-         _4 = ((_1 as V1).0: i32);        // scope 1 at $DIR/enum.rs:+2:29: +2:30
+-         _2 = _4;                         // scope 3 at $DIR/enum.rs:+2:35: +2:36
++         _4 = const 0_i32;                // scope 1 at $DIR/enum.rs:+2:29: +2:30
++         _2 = const 0_i32;                // scope 3 at $DIR/enum.rs:+2:35: +2:36
           StorageDead(_4);                 // scope 1 at $DIR/enum.rs:+2:35: +2:36
           goto -> bb4;                     // scope 1 at $DIR/enum.rs:+2:35: +2:36
       }
   
       bb4: {
-          _0 = const ();                   // scope 0 at $DIR/enum.rs:+0:11: +3:2
+          _0 = const ();                   // scope 0 at $DIR/enum.rs:+0:13: +3:2
           StorageDead(_2);                 // scope 1 at $DIR/enum.rs:+3:1: +3:2
           StorageDead(_1);                 // scope 0 at $DIR/enum.rs:+3:1: +3:2
           return;                          // scope 0 at $DIR/enum.rs:+3:2: +3:2
diff --git a/tests/mir-opt/dataflow-const-prop/inherit_overflow.main.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/inherit_overflow.main.DataflowConstProp.diff
index 02aafd7ac..29781e9ce 100644
--- a/tests/mir-opt/dataflow-const-prop/inherit_overflow.main.DataflowConstProp.diff
+++ b/tests/mir-opt/dataflow-const-prop/inherit_overflow.main.DataflowConstProp.diff
@@ -5,34 +5,34 @@
       let mut _0: ();                      // return place in scope 0 at $DIR/inherit_overflow.rs:+0:11: +0:11
       let mut _1: u8;                      // in scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
       let mut _2: u8;                      // in scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+      let mut _3: u8;                      // in scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
       scope 1 {
       }
-      scope 2 (inlined <u8 as Add>::add) { // at $DIR/inherit_overflow.rs:7:13: 7:47
-          debug self => _1;                // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          debug other => _2;               // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          let mut _3: u8;                  // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          let mut _4: u8;                  // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          let mut _5: (u8, bool);          // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+      scope 2 (inlined <u8 as Add>::add) { // at $DIR/inherit_overflow.rs:8:13: 8:47
+          debug self => _2;                // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          debug other => _3;               // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          let mut _4: (u8, bool);          // in scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
       }
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
-          _1 = const u8::MAX;              // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
           StorageLive(_2);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
-          _2 = const 1_u8;                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
-          StorageLive(_3);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          _3 = const u8::MAX;              // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          StorageLive(_4);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          _4 = const 1_u8;                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          _5 = CheckedAdd(const u8::MAX, const 1_u8); // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          assert(!move (_5.1: bool), "attempt to compute `{} + {}`, which would overflow", const u8::MAX, const 1_u8) -> bb1; // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          _2 = const u8::MAX;              // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageLive(_3);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          _3 = const 1_u8;                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+-         _4 = CheckedAdd(_2, _3);         // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+-         assert(!move (_4.1: bool), "attempt to compute `{} + {}`, which would overflow", _2, _3) -> bb1; // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
++         _4 = CheckedAdd(const u8::MAX, const 1_u8); // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
++         assert(!const true, "attempt to compute `{} + {}`, which would overflow", const u8::MAX, const 1_u8) -> bb1; // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
       }
   
       bb1: {
-          StorageDead(_4);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
-          StorageDead(_3);                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+-         _1 = move (_4.0: u8);            // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
++         _1 = const 0_u8;                 // scope 2 at $SRC_DIR/core/src/ops/arith.rs:LL:COL
+          StorageDead(_3);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
           StorageDead(_2);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
-          StorageDead(_1);                 // scope 0 at $DIR/inherit_overflow.rs:+3:13: +3:47
+          StorageDead(_1);                 // scope 0 at $DIR/inherit_overflow.rs:+3:47: +3:48
+          _0 = const ();                   // scope 0 at $DIR/inherit_overflow.rs:+0:11: +4:2
           return;                          // scope 0 at $DIR/inherit_overflow.rs:+4:2: +4:2
       }
   }
diff --git a/tests/mir-opt/dataflow-const-prop/inherit_overflow.rs b/tests/mir-opt/dataflow-const-prop/inherit_overflow.rs
index 2f2d9d010..f4aba60f0 100644
--- a/tests/mir-opt/dataflow-const-prop/inherit_overflow.rs
+++ b/tests/mir-opt/dataflow-const-prop/inherit_overflow.rs
@@ -1,8 +1,9 @@
-// compile-flags: -Zunsound-mir-opts
+// unit-test: DataflowConstProp
+// compile-flags: -Zmir-enable-passes=+Inline
 
 // EMIT_MIR inherit_overflow.main.DataflowConstProp.diff
 fn main() {
-    // After inlining, this will contain a `CheckedBinaryOp`. The overflow
-    // must be ignored by the constant propagation to avoid triggering a panic.
+    // After inlining, this will contain a `CheckedBinaryOp`.
+    // Propagating the overflow is ok as codegen will just skip emitting the panic.
     let _ = <u8 as std::ops::Add>::add(255, 1);
 }
diff --git a/tests/mir-opt/dataflow-const-prop/repr_transparent.main.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/repr_transparent.main.DataflowConstProp.diff
index f66b00a9a..8f045eedf 100644
--- a/tests/mir-opt/dataflow-const-prop/repr_transparent.main.DataflowConstProp.diff
+++ b/tests/mir-opt/dataflow-const-prop/repr_transparent.main.DataflowConstProp.diff
@@ -17,8 +17,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/repr_transparent.rs:+1:9: +1:10
-          Deinit(_1);                      // scope 0 at $DIR/repr_transparent.rs:+1:13: +1:19
-          (_1.0: i32) = const 0_i32;       // scope 0 at $DIR/repr_transparent.rs:+1:13: +1:19
+          _1 = I32(const 0_i32);           // scope 0 at $DIR/repr_transparent.rs:+1:13: +1:19
           StorageLive(_2);                 // scope 1 at $DIR/repr_transparent.rs:+2:9: +2:10
           StorageLive(_3);                 // scope 1 at $DIR/repr_transparent.rs:+2:17: +2:26
           StorageLive(_4);                 // scope 1 at $DIR/repr_transparent.rs:+2:17: +2:20
@@ -31,9 +30,8 @@
 +         _3 = const 0_i32;                // scope 1 at $DIR/repr_transparent.rs:+2:17: +2:26
           StorageDead(_5);                 // scope 1 at $DIR/repr_transparent.rs:+2:25: +2:26
           StorageDead(_4);                 // scope 1 at $DIR/repr_transparent.rs:+2:25: +2:26
-          Deinit(_2);                      // scope 1 at $DIR/repr_transparent.rs:+2:13: +2:27
--         (_2.0: i32) = move _3;           // scope 1 at $DIR/repr_transparent.rs:+2:13: +2:27
-+         (_2.0: i32) = const 0_i32;       // scope 1 at $DIR/repr_transparent.rs:+2:13: +2:27
+-         _2 = I32(move _3);               // scope 1 at $DIR/repr_transparent.rs:+2:13: +2:27
++         _2 = I32(const 0_i32);           // scope 1 at $DIR/repr_transparent.rs:+2:13: +2:27
           StorageDead(_3);                 // scope 1 at $DIR/repr_transparent.rs:+2:26: +2:27
           _0 = const ();                   // scope 0 at $DIR/repr_transparent.rs:+0:11: +3:2
           StorageDead(_2);                 // scope 1 at $DIR/repr_transparent.rs:+3:1: +3:2
diff --git a/tests/mir-opt/dataflow-const-prop/sibling_ptr.main.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/sibling_ptr.main.DataflowConstProp.diff
index 8126d4b85..004643e36 100644
--- a/tests/mir-opt/dataflow-const-prop/sibling_ptr.main.DataflowConstProp.diff
+++ b/tests/mir-opt/dataflow-const-prop/sibling_ptr.main.DataflowConstProp.diff
@@ -23,9 +23,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/sibling_ptr.rs:+1:9: +1:14
-          Deinit(_1);                      // scope 0 at $DIR/sibling_ptr.rs:+1:27: +1:33
-          (_1.0: u8) = const 0_u8;         // scope 0 at $DIR/sibling_ptr.rs:+1:27: +1:33
-          (_1.1: u8) = const 0_u8;         // scope 0 at $DIR/sibling_ptr.rs:+1:27: +1:33
+          _1 = (const 0_u8, const 0_u8);   // scope 0 at $DIR/sibling_ptr.rs:+1:27: +1:33
           StorageLive(_2);                 // scope 1 at $DIR/sibling_ptr.rs:+2:5: +5:6
           StorageLive(_3);                 // scope 2 at $DIR/sibling_ptr.rs:+3:13: +3:14
           _3 = &raw mut (_1.0: u8);        // scope 2 at $SRC_DIR/core/src/ptr/mod.rs:LL:COL
@@ -34,7 +32,7 @@
           _5 = _3;                         // scope 3 at $DIR/sibling_ptr.rs:+4:10: +4:11
           _4 = ptr::mut_ptr::<impl *mut u8>::add(move _5, const 1_usize) -> bb1; // scope 3 at $DIR/sibling_ptr.rs:+4:10: +4:18
                                            // mir::Constant
-                                           // + span: $DIR/sibling_ptr.rs:8:12: 8:15
+                                           // + span: $DIR/sibling_ptr.rs:15:12: 15:15
                                            // + literal: Const { ty: unsafe fn(*mut u8, usize) -> *mut u8 {ptr::mut_ptr::<impl *mut u8>::add}, val: Value(<ZST>) }
       }
   
diff --git a/tests/mir-opt/dataflow-const-prop/sibling_ptr.rs b/tests/mir-opt/dataflow-const-prop/sibling_ptr.rs
index 87ef00d18..6dfb3a4ed 100644
--- a/tests/mir-opt/dataflow-const-prop/sibling_ptr.rs
+++ b/tests/mir-opt/dataflow-const-prop/sibling_ptr.rs
@@ -1,3 +1,10 @@
+// This attempts to modify `x.1` via a pointer derived from `addr_of_mut!(x.0)`.
+// According to Miri, that is UB. However, T-opsem has not finalized that
+// decision and as such we cannot rely on it in optimizations. Consequently,
+// DataflowConstProp must treat the `addr_of_mut!(x.0)` as potentially being
+// used to modify `x.1` - if it did not, then it might incorrectly assume that it
+// can infer the value of `x.1` at the end of this function.
+
 // unit-test: DataflowConstProp
 
 // EMIT_MIR sibling_ptr.main.DataflowConstProp.diff
@@ -7,5 +14,5 @@ fn main() {
         let p = std::ptr::addr_of_mut!(x.0);
         *p.add(1) = 1;
     }
-    let x1 = x.1;  // should not be propagated
+    let x1 = x.1; // should not be propagated
 }
diff --git a/tests/mir-opt/dataflow-const-prop/struct.main.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/struct.main.DataflowConstProp.diff
index cfb2706c1..53c62c081 100644
--- a/tests/mir-opt/dataflow-const-prop/struct.main.DataflowConstProp.diff
+++ b/tests/mir-opt/dataflow-const-prop/struct.main.DataflowConstProp.diff
@@ -21,8 +21,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/struct.rs:+1:9: +1:14
-          Deinit(_1);                      // scope 0 at $DIR/struct.rs:+1:17: +1:21
-          (_1.0: i32) = const 1_i32;       // scope 0 at $DIR/struct.rs:+1:17: +1:21
+          _1 = S(const 1_i32);             // scope 0 at $DIR/struct.rs:+1:17: +1:21
           StorageLive(_2);                 // scope 1 at $DIR/struct.rs:+2:9: +2:10
           StorageLive(_3);                 // scope 1 at $DIR/struct.rs:+2:13: +2:16
 -         _3 = (_1.0: i32);                // scope 1 at $DIR/struct.rs:+2:13: +2:16
diff --git a/tests/mir-opt/dataflow-const-prop/tuple.main.DataflowConstProp.diff b/tests/mir-opt/dataflow-const-prop/tuple.main.DataflowConstProp.diff
index e028def00..8ce4ce4ba 100644
--- a/tests/mir-opt/dataflow-const-prop/tuple.main.DataflowConstProp.diff
+++ b/tests/mir-opt/dataflow-const-prop/tuple.main.DataflowConstProp.diff
@@ -25,9 +25,7 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/tuple.rs:+1:9: +1:14
-          Deinit(_1);                      // scope 0 at $DIR/tuple.rs:+1:17: +1:23
-          (_1.0: i32) = const 1_i32;       // scope 0 at $DIR/tuple.rs:+1:17: +1:23
-          (_1.1: i32) = const 2_i32;       // scope 0 at $DIR/tuple.rs:+1:17: +1:23
+          _1 = (const 1_i32, const 2_i32); // scope 0 at $DIR/tuple.rs:+1:17: +1:23
           StorageLive(_2);                 // scope 1 at $DIR/tuple.rs:+2:9: +2:10
           StorageLive(_3);                 // scope 1 at $DIR/tuple.rs:+2:13: +2:22
           StorageLive(_4);                 // scope 1 at $DIR/tuple.rs:+2:13: +2:16
@@ -43,9 +41,7 @@
 -         _2 = Add(move _3, const 3_i32);  // scope 1 at $DIR/tuple.rs:+2:13: +2:26
 +         _2 = const 6_i32;                // scope 1 at $DIR/tuple.rs:+2:13: +2:26
           StorageDead(_3);                 // scope 1 at $DIR/tuple.rs:+2:25: +2:26
-          Deinit(_1);                      // scope 2 at $DIR/tuple.rs:+3:5: +3:15
-          (_1.0: i32) = const 2_i32;       // scope 2 at $DIR/tuple.rs:+3:5: +3:15
-          (_1.1: i32) = const 3_i32;       // scope 2 at $DIR/tuple.rs:+3:5: +3:15
+          _1 = (const 2_i32, const 3_i32); // scope 2 at $DIR/tuple.rs:+3:5: +3:15
           StorageLive(_6);                 // scope 2 at $DIR/tuple.rs:+4:9: +4:10
           StorageLive(_7);                 // scope 2 at $DIR/tuple.rs:+4:13: +4:22
           StorageLive(_8);                 // scope 2 at $DIR/tuple.rs:+4:13: +4:16
diff --git a/tests/mir-opt/deaggregator_test.bar.Deaggregator.diff b/tests/mir-opt/deaggregator_test.bar.Deaggregator.diff
deleted file mode 100644
index db136485a..000000000
--- a/tests/mir-opt/deaggregator_test.bar.Deaggregator.diff
+++ /dev/null
@@ -1,21 +0,0 @@
-- // MIR for `bar` before Deaggregator
-+ // MIR for `bar` after Deaggregator
-  
-  fn bar(_1: usize) -> Baz {
-      debug a => _1;                       // in scope 0 at $DIR/deaggregator_test.rs:+0:8: +0:9
-      let mut _0: Baz;                     // return place in scope 0 at $DIR/deaggregator_test.rs:+0:21: +0:24
-      let mut _2: usize;                   // in scope 0 at $DIR/deaggregator_test.rs:+1:14: +1:15
-  
-      bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/deaggregator_test.rs:+1:14: +1:15
-          _2 = _1;                         // scope 0 at $DIR/deaggregator_test.rs:+1:14: +1:15
--         _0 = Baz { x: move _2, y: const 0f32, z: const false }; // scope 0 at $DIR/deaggregator_test.rs:+1:5: +1:35
-+         Deinit(_0);                      // scope 0 at $DIR/deaggregator_test.rs:+1:5: +1:35
-+         (_0.0: usize) = move _2;         // scope 0 at $DIR/deaggregator_test.rs:+1:5: +1:35
-+         (_0.1: f32) = const 0f32;        // scope 0 at $DIR/deaggregator_test.rs:+1:5: +1:35
-+         (_0.2: bool) = const false;      // scope 0 at $DIR/deaggregator_test.rs:+1:5: +1:35
-          StorageDead(_2);                 // scope 0 at $DIR/deaggregator_test.rs:+1:34: +1:35
-          return;                          // scope 0 at $DIR/deaggregator_test.rs:+2:2: +2:2
-      }
-  }
-  
diff --git a/tests/mir-opt/deaggregator_test.rs b/tests/mir-opt/deaggregator_test.rs
deleted file mode 100644
index ee59402af..000000000
--- a/tests/mir-opt/deaggregator_test.rs
+++ /dev/null
@@ -1,17 +0,0 @@
-// unit-test: Deaggregator
-
-struct Baz {
-    x: usize,
-    y: f32,
-    z: bool,
-}
-
-// EMIT_MIR deaggregator_test.bar.Deaggregator.diff
-fn bar(a: usize) -> Baz {
-    Baz { x: a, y: 0.0, z: false }
-}
-
-fn main() {
-    // Make sure the function actually gets instantiated.
-    bar(0);
-}
diff --git a/tests/mir-opt/deaggregator_test_enum.bar.Deaggregator.diff b/tests/mir-opt/deaggregator_test_enum.bar.Deaggregator.diff
deleted file mode 100644
index f28c2b482..000000000
--- a/tests/mir-opt/deaggregator_test_enum.bar.Deaggregator.diff
+++ /dev/null
@@ -1,20 +0,0 @@
-- // MIR for `bar` before Deaggregator
-+ // MIR for `bar` after Deaggregator
-  
-  fn bar(_1: usize) -> Baz {
-      debug a => _1;                       // in scope 0 at $DIR/deaggregator_test_enum.rs:+0:8: +0:9
-      let mut _0: Baz;                     // return place in scope 0 at $DIR/deaggregator_test_enum.rs:+0:21: +0:24
-      let mut _2: usize;                   // in scope 0 at $DIR/deaggregator_test_enum.rs:+1:19: +1:20
-  
-      bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/deaggregator_test_enum.rs:+1:19: +1:20
-          _2 = _1;                         // scope 0 at $DIR/deaggregator_test_enum.rs:+1:19: +1:20
--         _0 = Baz::Foo { x: move _2 };    // scope 0 at $DIR/deaggregator_test_enum.rs:+1:5: +1:22
-+         Deinit(_0);                      // scope 0 at $DIR/deaggregator_test_enum.rs:+1:5: +1:22
-+         ((_0 as Foo).0: usize) = move _2; // scope 0 at $DIR/deaggregator_test_enum.rs:+1:5: +1:22
-+         discriminant(_0) = 1;            // scope 0 at $DIR/deaggregator_test_enum.rs:+1:5: +1:22
-          StorageDead(_2);                 // scope 0 at $DIR/deaggregator_test_enum.rs:+1:21: +1:22
-          return;                          // scope 0 at $DIR/deaggregator_test_enum.rs:+2:2: +2:2
-      }
-  }
-  
diff --git a/tests/mir-opt/deaggregator_test_enum.rs b/tests/mir-opt/deaggregator_test_enum.rs
deleted file mode 100644
index ea402dafd..000000000
--- a/tests/mir-opt/deaggregator_test_enum.rs
+++ /dev/null
@@ -1,19 +0,0 @@
-// unit-test: Deaggregator
-
-enum Baz {
-    Empty,
-    Foo { x: usize },
-}
-
-// EMIT_MIR deaggregator_test_enum.bar.Deaggregator.diff
-fn bar(a: usize) -> Baz {
-    Baz::Foo { x: a }
-}
-
-fn main() {
-    let x = bar(10);
-    match x {
-        Baz::Empty => println!("empty"),
-        Baz::Foo { x } => println!("{}", x),
-    };
-}
diff --git a/tests/mir-opt/deaggregator_test_enum_2.rs b/tests/mir-opt/deaggregator_test_enum_2.rs
deleted file mode 100644
index 955c31732..000000000
--- a/tests/mir-opt/deaggregator_test_enum_2.rs
+++ /dev/null
@@ -1,21 +0,0 @@
-// unit-test: Deaggregator
-// Test that deaggregate fires in more than one basic block
-
-enum Foo {
-    A(i32),
-    B(i32),
-}
-
-// EMIT_MIR deaggregator_test_enum_2.test1.Deaggregator.diff
-fn test1(x: bool, y: i32) -> Foo {
-    if x {
-        Foo::A(y)
-    } else {
-        Foo::B(y)
-    }
-}
-
-fn main() {
-    // Make sure the function actually gets instantiated.
-    test1(false, 0);
-}
diff --git a/tests/mir-opt/deaggregator_test_enum_2.test1.Deaggregator.diff b/tests/mir-opt/deaggregator_test_enum_2.test1.Deaggregator.diff
deleted file mode 100644
index 210d3849e..000000000
--- a/tests/mir-opt/deaggregator_test_enum_2.test1.Deaggregator.diff
+++ /dev/null
@@ -1,45 +0,0 @@
-- // MIR for `test1` before Deaggregator
-+ // MIR for `test1` after Deaggregator
-  
-  fn test1(_1: bool, _2: i32) -> Foo {
-      debug x => _1;                       // in scope 0 at $DIR/deaggregator_test_enum_2.rs:+0:10: +0:11
-      debug y => _2;                       // in scope 0 at $DIR/deaggregator_test_enum_2.rs:+0:19: +0:20
-      let mut _0: Foo;                     // return place in scope 0 at $DIR/deaggregator_test_enum_2.rs:+0:30: +0:33
-      let mut _3: bool;                    // in scope 0 at $DIR/deaggregator_test_enum_2.rs:+1:8: +1:9
-      let mut _4: i32;                     // in scope 0 at $DIR/deaggregator_test_enum_2.rs:+2:16: +2:17
-      let mut _5: i32;                     // in scope 0 at $DIR/deaggregator_test_enum_2.rs:+4:16: +4:17
-  
-      bb0: {
-          StorageLive(_3);                 // scope 0 at $DIR/deaggregator_test_enum_2.rs:+1:8: +1:9
-          _3 = _1;                         // scope 0 at $DIR/deaggregator_test_enum_2.rs:+1:8: +1:9
-          switchInt(move _3) -> [0: bb2, otherwise: bb1]; // scope 0 at $DIR/deaggregator_test_enum_2.rs:+1:8: +1:9
-      }
-  
-      bb1: {
-          StorageLive(_4);                 // scope 0 at $DIR/deaggregator_test_enum_2.rs:+2:16: +2:17
-          _4 = _2;                         // scope 0 at $DIR/deaggregator_test_enum_2.rs:+2:16: +2:17
--         _0 = Foo::A(move _4);            // scope 0 at $DIR/deaggregator_test_enum_2.rs:+2:9: +2:18
-+         Deinit(_0);                      // scope 0 at $DIR/deaggregator_test_enum_2.rs:+2:9: +2:18
-+         ((_0 as A).0: i32) = move _4;    // scope 0 at $DIR/deaggregator_test_enum_2.rs:+2:9: +2:18
-+         discriminant(_0) = 0;            // scope 0 at $DIR/deaggregator_test_enum_2.rs:+2:9: +2:18
-          StorageDead(_4);                 // scope 0 at $DIR/deaggregator_test_enum_2.rs:+2:17: +2:18
-          goto -> bb3;                     // scope 0 at $DIR/deaggregator_test_enum_2.rs:+1:5: +5:6
-      }
-  
-      bb2: {
-          StorageLive(_5);                 // scope 0 at $DIR/deaggregator_test_enum_2.rs:+4:16: +4:17
-          _5 = _2;                         // scope 0 at $DIR/deaggregator_test_enum_2.rs:+4:16: +4:17
--         _0 = Foo::B(move _5);            // scope 0 at $DIR/deaggregator_test_enum_2.rs:+4:9: +4:18
-+         Deinit(_0);                      // scope 0 at $DIR/deaggregator_test_enum_2.rs:+4:9: +4:18
-+         ((_0 as B).0: i32) = move _5;    // scope 0 at $DIR/deaggregator_test_enum_2.rs:+4:9: +4:18
-+         discriminant(_0) = 1;            // scope 0 at $DIR/deaggregator_test_enum_2.rs:+4:9: +4:18
-          StorageDead(_5);                 // scope 0 at $DIR/deaggregator_test_enum_2.rs:+4:17: +4:18
-          goto -> bb3;                     // scope 0 at $DIR/deaggregator_test_enum_2.rs:+1:5: +5:6
-      }
-  
-      bb3: {
-          StorageDead(_3);                 // scope 0 at $DIR/deaggregator_test_enum_2.rs:+5:5: +5:6
-          return;                          // scope 0 at $DIR/deaggregator_test_enum_2.rs:+6:2: +6:2
-      }
-  }
-  
diff --git a/tests/mir-opt/deaggregator_test_multiple.rs b/tests/mir-opt/deaggregator_test_multiple.rs
deleted file mode 100644
index 46305fe21..000000000
--- a/tests/mir-opt/deaggregator_test_multiple.rs
+++ /dev/null
@@ -1,17 +0,0 @@
-// unit-test: Deaggregator
-// Test that deaggregate fires more than once per block
-
-enum Foo {
-    A(i32),
-    B,
-}
-
-// EMIT_MIR deaggregator_test_multiple.test.Deaggregator.diff
-fn test(x: i32) -> [Foo; 2] {
-    [Foo::A(x), Foo::A(x)]
-}
-
-fn main() {
-    // Make sure the function actually gets instantiated.
-    test(0);
-}
diff --git a/tests/mir-opt/deaggregator_test_multiple.test.Deaggregator.diff b/tests/mir-opt/deaggregator_test_multiple.test.Deaggregator.diff
deleted file mode 100644
index cf5da273c..000000000
--- a/tests/mir-opt/deaggregator_test_multiple.test.Deaggregator.diff
+++ /dev/null
@@ -1,35 +0,0 @@
-- // MIR for `test` before Deaggregator
-+ // MIR for `test` after Deaggregator
-  
-  fn test(_1: i32) -> [Foo; 2] {
-      debug x => _1;                       // in scope 0 at $DIR/deaggregator_test_multiple.rs:+0:9: +0:10
-      let mut _0: [Foo; 2];                // return place in scope 0 at $DIR/deaggregator_test_multiple.rs:+0:20: +0:28
-      let mut _2: Foo;                     // in scope 0 at $DIR/deaggregator_test_multiple.rs:+1:6: +1:15
-      let mut _3: i32;                     // in scope 0 at $DIR/deaggregator_test_multiple.rs:+1:13: +1:14
-      let mut _4: Foo;                     // in scope 0 at $DIR/deaggregator_test_multiple.rs:+1:17: +1:26
-      let mut _5: i32;                     // in scope 0 at $DIR/deaggregator_test_multiple.rs:+1:24: +1:25
-  
-      bb0: {
-          StorageLive(_2);                 // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:6: +1:15
-          StorageLive(_3);                 // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:13: +1:14
-          _3 = _1;                         // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:13: +1:14
--         _2 = Foo::A(move _3);            // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:6: +1:15
-+         Deinit(_2);                      // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:6: +1:15
-+         ((_2 as A).0: i32) = move _3;    // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:6: +1:15
-+         discriminant(_2) = 0;            // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:6: +1:15
-          StorageDead(_3);                 // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:14: +1:15
-          StorageLive(_4);                 // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:17: +1:26
-          StorageLive(_5);                 // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:24: +1:25
-          _5 = _1;                         // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:24: +1:25
--         _4 = Foo::A(move _5);            // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:17: +1:26
-+         Deinit(_4);                      // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:17: +1:26
-+         ((_4 as A).0: i32) = move _5;    // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:17: +1:26
-+         discriminant(_4) = 0;            // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:17: +1:26
-          StorageDead(_5);                 // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:25: +1:26
-          _0 = [move _2, move _4];         // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:5: +1:27
-          StorageDead(_4);                 // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:26: +1:27
-          StorageDead(_2);                 // scope 0 at $DIR/deaggregator_test_multiple.rs:+1:26: +1:27
-          return;                          // scope 0 at $DIR/deaggregator_test_multiple.rs:+2:2: +2:2
-      }
-  }
-  
diff --git a/tests/mir-opt/div_overflow.const_dividend.PreCodegen.after.mir b/tests/mir-opt/div_overflow.const_dividend.PreCodegen.after.mir
index d7f66a6bf..1a7fb916e 100644
--- a/tests/mir-opt/div_overflow.const_dividend.PreCodegen.after.mir
+++ b/tests/mir-opt/div_overflow.const_dividend.PreCodegen.after.mir
@@ -11,7 +11,7 @@ fn const_dividend(_1: i32) -> i32 {
     }
 
     bb1: {
-        _0 = Div(const 256_i32, move _1); // scope 0 at $DIR/div_overflow.rs:+1:5: +1:12
+        _0 = Div(const 256_i32, _1);     // scope 0 at $DIR/div_overflow.rs:+1:5: +1:12
         return;                          // scope 0 at $DIR/div_overflow.rs:+2:2: +2:2
     }
 }
diff --git a/tests/mir-opt/div_overflow.const_divisor.PreCodegen.after.mir b/tests/mir-opt/div_overflow.const_divisor.PreCodegen.after.mir
index 7b7ab1978..5526a194b 100644
--- a/tests/mir-opt/div_overflow.const_divisor.PreCodegen.after.mir
+++ b/tests/mir-opt/div_overflow.const_divisor.PreCodegen.after.mir
@@ -5,7 +5,7 @@ fn const_divisor(_1: i32) -> i32 {
     let mut _0: i32;                     // return place in scope 0 at $DIR/div_overflow.rs:+0:33: +0:36
 
     bb0: {
-        _0 = Div(move _1, const 256_i32); // scope 0 at $DIR/div_overflow.rs:+1:5: +1:12
+        _0 = Div(_1, const 256_i32);     // scope 0 at $DIR/div_overflow.rs:+1:5: +1:12
         return;                          // scope 0 at $DIR/div_overflow.rs:+2:2: +2:2
     }
 }
diff --git a/tests/mir-opt/dont_yeet_assert.generic.InstCombine.diff b/tests/mir-opt/dont_yeet_assert.generic.InstCombine.diff
new file mode 100644
index 000000000..c1a42a47e
--- /dev/null
+++ b/tests/mir-opt/dont_yeet_assert.generic.InstCombine.diff
@@ -0,0 +1,23 @@
+- // MIR for `generic` before InstCombine
++ // MIR for `generic` after InstCombine
+  
+  fn generic() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/dont_yeet_assert.rs:+0:21: +0:21
+      let _1: ();                          // in scope 0 at $DIR/dont_yeet_assert.rs:+1:5: +1:61
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/dont_yeet_assert.rs:+1:5: +1:61
+          _1 = assert_mem_uninitialized_valid::<&T>() -> bb1; // scope 0 at $DIR/dont_yeet_assert.rs:+1:5: +1:61
+                                           // mir::Constant
+                                           // + span: $DIR/dont_yeet_assert.rs:10:5: 10:59
+                                           // + user_ty: UserType(0)
+                                           // + literal: Const { ty: extern "rust-intrinsic" fn() {assert_mem_uninitialized_valid::<&T>}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_1);                 // scope 0 at $DIR/dont_yeet_assert.rs:+1:61: +1:62
+          _0 = const ();                   // scope 0 at $DIR/dont_yeet_assert.rs:+0:21: +2:2
+          return;                          // scope 0 at $DIR/dont_yeet_assert.rs:+2:2: +2:2
+      }
+  }
+  
diff --git a/tests/mir-opt/dont_yeet_assert.rs b/tests/mir-opt/dont_yeet_assert.rs
new file mode 100644
index 000000000..7cec761ea
--- /dev/null
+++ b/tests/mir-opt/dont_yeet_assert.rs
@@ -0,0 +1,11 @@
+// compile-flags: --crate-type=lib
+// unit-test: InstCombine
+
+#![feature(core_intrinsics)]
+
+// Want to make sure this assertion isn't compiled away in generic code.
+
+// EMIT_MIR dont_yeet_assert.generic.InstCombine.diff
+pub fn generic<T>() {
+    core::intrinsics::assert_mem_uninitialized_valid::<&T>();
+}
diff --git a/tests/mir-opt/early_otherwise_branch.opt1.EarlyOtherwiseBranch.diff b/tests/mir-opt/early_otherwise_branch.opt1.EarlyOtherwiseBranch.diff
index 98a02ee38..5383d1be1 100644
--- a/tests/mir-opt/early_otherwise_branch.opt1.EarlyOtherwiseBranch.diff
+++ b/tests/mir-opt/early_otherwise_branch.opt1.EarlyOtherwiseBranch.diff
@@ -25,9 +25,7 @@
           _4 = _1;                         // scope 0 at $DIR/early_otherwise_branch.rs:+1:12: +1:13
           StorageLive(_5);                 // scope 0 at $DIR/early_otherwise_branch.rs:+1:15: +1:16
           _5 = _2;                         // scope 0 at $DIR/early_otherwise_branch.rs:+1:15: +1:16
-          Deinit(_3);                      // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
-          (_3.0: std::option::Option<u32>) = move _4; // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
-          (_3.1: std::option::Option<u32>) = move _5; // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
+          _3 = (move _4, move _5);         // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
           StorageDead(_5);                 // scope 0 at $DIR/early_otherwise_branch.rs:+1:16: +1:17
           StorageDead(_4);                 // scope 0 at $DIR/early_otherwise_branch.rs:+1:16: +1:17
           _7 = discriminant((_3.0: std::option::Option<u32>)); // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
diff --git a/tests/mir-opt/early_otherwise_branch.opt2.EarlyOtherwiseBranch.diff b/tests/mir-opt/early_otherwise_branch.opt2.EarlyOtherwiseBranch.diff
index aa75c44b8..b3e21ff49 100644
--- a/tests/mir-opt/early_otherwise_branch.opt2.EarlyOtherwiseBranch.diff
+++ b/tests/mir-opt/early_otherwise_branch.opt2.EarlyOtherwiseBranch.diff
@@ -26,9 +26,7 @@
           _4 = _1;                         // scope 0 at $DIR/early_otherwise_branch.rs:+1:12: +1:13
           StorageLive(_5);                 // scope 0 at $DIR/early_otherwise_branch.rs:+1:15: +1:16
           _5 = _2;                         // scope 0 at $DIR/early_otherwise_branch.rs:+1:15: +1:16
-          Deinit(_3);                      // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
-          (_3.0: std::option::Option<u32>) = move _4; // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
-          (_3.1: std::option::Option<u32>) = move _5; // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
+          _3 = (move _4, move _5);         // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
           StorageDead(_5);                 // scope 0 at $DIR/early_otherwise_branch.rs:+1:16: +1:17
           StorageDead(_4);                 // scope 0 at $DIR/early_otherwise_branch.rs:+1:16: +1:17
           _8 = discriminant((_3.0: std::option::Option<u32>)); // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
diff --git a/tests/mir-opt/early_otherwise_branch.opt3.EarlyOtherwiseBranch.diff b/tests/mir-opt/early_otherwise_branch.opt3.EarlyOtherwiseBranch.diff
index cea6ff7cd..e098a88eb 100644
--- a/tests/mir-opt/early_otherwise_branch.opt3.EarlyOtherwiseBranch.diff
+++ b/tests/mir-opt/early_otherwise_branch.opt3.EarlyOtherwiseBranch.diff
@@ -25,9 +25,7 @@
           _4 = _1;                         // scope 0 at $DIR/early_otherwise_branch.rs:+1:12: +1:13
           StorageLive(_5);                 // scope 0 at $DIR/early_otherwise_branch.rs:+1:15: +1:16
           _5 = _2;                         // scope 0 at $DIR/early_otherwise_branch.rs:+1:15: +1:16
-          Deinit(_3);                      // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
-          (_3.0: std::option::Option<u32>) = move _4; // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
-          (_3.1: std::option::Option<bool>) = move _5; // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
+          _3 = (move _4, move _5);         // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
           StorageDead(_5);                 // scope 0 at $DIR/early_otherwise_branch.rs:+1:16: +1:17
           StorageDead(_4);                 // scope 0 at $DIR/early_otherwise_branch.rs:+1:16: +1:17
           _7 = discriminant((_3.0: std::option::Option<u32>)); // scope 0 at $DIR/early_otherwise_branch.rs:+1:11: +1:17
diff --git a/tests/mir-opt/early_otherwise_branch_3_element_tuple.opt1.EarlyOtherwiseBranch.diff b/tests/mir-opt/early_otherwise_branch_3_element_tuple.opt1.EarlyOtherwiseBranch.diff
index b90d70ce4..ec3b4bbdf 100644
--- a/tests/mir-opt/early_otherwise_branch_3_element_tuple.opt1.EarlyOtherwiseBranch.diff
+++ b/tests/mir-opt/early_otherwise_branch_3_element_tuple.opt1.EarlyOtherwiseBranch.diff
@@ -34,10 +34,7 @@
           _6 = _2;                         // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:15: +1:16
           StorageLive(_7);                 // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:18: +1:19
           _7 = _3;                         // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:18: +1:19
-          Deinit(_4);                      // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:11: +1:20
-          (_4.0: std::option::Option<u32>) = move _5; // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:11: +1:20
-          (_4.1: std::option::Option<u32>) = move _6; // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:11: +1:20
-          (_4.2: std::option::Option<u32>) = move _7; // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:11: +1:20
+          _4 = (move _5, move _6, move _7); // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:11: +1:20
           StorageDead(_7);                 // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:19: +1:20
           StorageDead(_6);                 // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:19: +1:20
           StorageDead(_5);                 // scope 0 at $DIR/early_otherwise_branch_3_element_tuple.rs:+1:19: +1:20
diff --git a/tests/mir-opt/early_otherwise_branch_68867.try_sum.EarlyOtherwiseBranch.diff b/tests/mir-opt/early_otherwise_branch_68867.try_sum.EarlyOtherwiseBranch.diff
index 9edd1a39f..a91d0d7cf 100644
--- a/tests/mir-opt/early_otherwise_branch_68867.try_sum.EarlyOtherwiseBranch.diff
+++ b/tests/mir-opt/early_otherwise_branch_68867.try_sum.EarlyOtherwiseBranch.diff
@@ -73,9 +73,7 @@
           _5 = _1;                         // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:15: +5:16
           StorageLive(_6);                 // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:18: +5:23
           _6 = _2;                         // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:18: +5:23
-          Deinit(_4);                      // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:14: +5:24
-          (_4.0: &ViewportPercentageLength) = move _5; // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:14: +5:24
-          (_4.1: &ViewportPercentageLength) = move _6; // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:14: +5:24
+          _4 = (move _5, move _6);         // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:14: +5:24
           StorageDead(_6);                 // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:23: +5:24
           StorageDead(_5);                 // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:23: +5:24
           _34 = deref_copy (_4.0: &ViewportPercentageLength); // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:14: +5:24
@@ -91,10 +89,8 @@
   
       bb2: {
           StorageLive(_33);                // scope 0 at $DIR/early_otherwise_branch_68867.rs:+10:25: +10:27
-          Deinit(_33);                     // scope 0 at $DIR/early_otherwise_branch_68867.rs:+10:25: +10:27
-          Deinit(_0);                      // scope 0 at $DIR/early_otherwise_branch_68867.rs:+10:21: +10:28
-          ((_0 as Err).0: ()) = move _33;  // scope 0 at $DIR/early_otherwise_branch_68867.rs:+10:21: +10:28
-          discriminant(_0) = 1;            // scope 0 at $DIR/early_otherwise_branch_68867.rs:+10:21: +10:28
+          _33 = ();                        // scope 0 at $DIR/early_otherwise_branch_68867.rs:+10:25: +10:27
+          _0 = Result::<ViewportPercentageLength, ()>::Err(move _33); // scope 0 at $DIR/early_otherwise_branch_68867.rs:+10:21: +10:28
           StorageDead(_33);                // scope 0 at $DIR/early_otherwise_branch_68867.rs:+10:27: +10:28
           StorageDead(_3);                 // scope 0 at $DIR/early_otherwise_branch_68867.rs:+11:6: +11:7
           StorageDead(_4);                 // scope 0 at $DIR/early_otherwise_branch_68867.rs:+12:1: +12:2
@@ -134,9 +130,7 @@
           _14 = Add(move _15, move _16);   // scope 1 at $DIR/early_otherwise_branch_68867.rs:+6:38: +6:49
           StorageDead(_16);                // scope 1 at $DIR/early_otherwise_branch_68867.rs:+6:48: +6:49
           StorageDead(_15);                // scope 1 at $DIR/early_otherwise_branch_68867.rs:+6:48: +6:49
-          Deinit(_3);                      // scope 1 at $DIR/early_otherwise_branch_68867.rs:+6:35: +6:50
-          ((_3 as Vw).0: f32) = move _14;  // scope 1 at $DIR/early_otherwise_branch_68867.rs:+6:35: +6:50
-          discriminant(_3) = 0;            // scope 1 at $DIR/early_otherwise_branch_68867.rs:+6:35: +6:50
+          _3 = ViewportPercentageLength::Vw(move _14); // scope 1 at $DIR/early_otherwise_branch_68867.rs:+6:35: +6:50
           StorageDead(_14);                // scope 1 at $DIR/early_otherwise_branch_68867.rs:+6:49: +6:50
           StorageDead(_13);                // scope 0 at $DIR/early_otherwise_branch_68867.rs:+6:49: +6:50
           StorageDead(_12);                // scope 0 at $DIR/early_otherwise_branch_68867.rs:+6:49: +6:50
@@ -158,9 +152,7 @@
           _19 = Add(move _20, move _21);   // scope 2 at $DIR/early_otherwise_branch_68867.rs:+7:38: +7:49
           StorageDead(_21);                // scope 2 at $DIR/early_otherwise_branch_68867.rs:+7:48: +7:49
           StorageDead(_20);                // scope 2 at $DIR/early_otherwise_branch_68867.rs:+7:48: +7:49
-          Deinit(_3);                      // scope 2 at $DIR/early_otherwise_branch_68867.rs:+7:35: +7:50
-          ((_3 as Vh).0: f32) = move _19;  // scope 2 at $DIR/early_otherwise_branch_68867.rs:+7:35: +7:50
-          discriminant(_3) = 1;            // scope 2 at $DIR/early_otherwise_branch_68867.rs:+7:35: +7:50
+          _3 = ViewportPercentageLength::Vh(move _19); // scope 2 at $DIR/early_otherwise_branch_68867.rs:+7:35: +7:50
           StorageDead(_19);                // scope 2 at $DIR/early_otherwise_branch_68867.rs:+7:49: +7:50
           StorageDead(_18);                // scope 0 at $DIR/early_otherwise_branch_68867.rs:+7:49: +7:50
           StorageDead(_17);                // scope 0 at $DIR/early_otherwise_branch_68867.rs:+7:49: +7:50
@@ -182,9 +174,7 @@
           _24 = Add(move _25, move _26);   // scope 3 at $DIR/early_otherwise_branch_68867.rs:+8:44: +8:55
           StorageDead(_26);                // scope 3 at $DIR/early_otherwise_branch_68867.rs:+8:54: +8:55
           StorageDead(_25);                // scope 3 at $DIR/early_otherwise_branch_68867.rs:+8:54: +8:55
-          Deinit(_3);                      // scope 3 at $DIR/early_otherwise_branch_68867.rs:+8:39: +8:56
-          ((_3 as Vmin).0: f32) = move _24; // scope 3 at $DIR/early_otherwise_branch_68867.rs:+8:39: +8:56
-          discriminant(_3) = 2;            // scope 3 at $DIR/early_otherwise_branch_68867.rs:+8:39: +8:56
+          _3 = ViewportPercentageLength::Vmin(move _24); // scope 3 at $DIR/early_otherwise_branch_68867.rs:+8:39: +8:56
           StorageDead(_24);                // scope 3 at $DIR/early_otherwise_branch_68867.rs:+8:55: +8:56
           StorageDead(_23);                // scope 0 at $DIR/early_otherwise_branch_68867.rs:+8:55: +8:56
           StorageDead(_22);                // scope 0 at $DIR/early_otherwise_branch_68867.rs:+8:55: +8:56
@@ -206,9 +196,7 @@
           _29 = Add(move _30, move _31);   // scope 4 at $DIR/early_otherwise_branch_68867.rs:+9:44: +9:55
           StorageDead(_31);                // scope 4 at $DIR/early_otherwise_branch_68867.rs:+9:54: +9:55
           StorageDead(_30);                // scope 4 at $DIR/early_otherwise_branch_68867.rs:+9:54: +9:55
-          Deinit(_3);                      // scope 4 at $DIR/early_otherwise_branch_68867.rs:+9:39: +9:56
-          ((_3 as Vmax).0: f32) = move _29; // scope 4 at $DIR/early_otherwise_branch_68867.rs:+9:39: +9:56
-          discriminant(_3) = 3;            // scope 4 at $DIR/early_otherwise_branch_68867.rs:+9:39: +9:56
+          _3 = ViewportPercentageLength::Vmax(move _29); // scope 4 at $DIR/early_otherwise_branch_68867.rs:+9:39: +9:56
           StorageDead(_29);                // scope 4 at $DIR/early_otherwise_branch_68867.rs:+9:55: +9:56
           StorageDead(_28);                // scope 0 at $DIR/early_otherwise_branch_68867.rs:+9:55: +9:56
           StorageDead(_27);                // scope 0 at $DIR/early_otherwise_branch_68867.rs:+9:55: +9:56
@@ -216,9 +204,7 @@
       }
   
       bb10: {
-          Deinit(_0);                      // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:5: +11:7
-          ((_0 as Ok).0: ViewportPercentageLength) = move _3; // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:5: +11:7
-          discriminant(_0) = 0;            // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:5: +11:7
+          _0 = Result::<ViewportPercentageLength, ()>::Ok(move _3); // scope 0 at $DIR/early_otherwise_branch_68867.rs:+5:5: +11:7
           StorageDead(_3);                 // scope 0 at $DIR/early_otherwise_branch_68867.rs:+11:6: +11:7
           StorageDead(_4);                 // scope 0 at $DIR/early_otherwise_branch_68867.rs:+12:1: +12:2
           goto -> bb11;                    // scope 0 at $DIR/early_otherwise_branch_68867.rs:+12:2: +12:2
diff --git a/tests/mir-opt/early_otherwise_branch_noopt.noopt1.EarlyOtherwiseBranch.diff b/tests/mir-opt/early_otherwise_branch_noopt.noopt1.EarlyOtherwiseBranch.diff
index 82d8b2fc5..6468eb5f8 100644
--- a/tests/mir-opt/early_otherwise_branch_noopt.noopt1.EarlyOtherwiseBranch.diff
+++ b/tests/mir-opt/early_otherwise_branch_noopt.noopt1.EarlyOtherwiseBranch.diff
@@ -32,9 +32,7 @@
           _4 = _1;                         // scope 0 at $DIR/early_otherwise_branch_noopt.rs:+1:12: +1:13
           StorageLive(_5);                 // scope 0 at $DIR/early_otherwise_branch_noopt.rs:+1:15: +1:16
           _5 = _2;                         // scope 0 at $DIR/early_otherwise_branch_noopt.rs:+1:15: +1:16
-          Deinit(_3);                      // scope 0 at $DIR/early_otherwise_branch_noopt.rs:+1:11: +1:17
-          (_3.0: std::option::Option<u32>) = move _4; // scope 0 at $DIR/early_otherwise_branch_noopt.rs:+1:11: +1:17
-          (_3.1: std::option::Option<u32>) = move _5; // scope 0 at $DIR/early_otherwise_branch_noopt.rs:+1:11: +1:17
+          _3 = (move _4, move _5);         // scope 0 at $DIR/early_otherwise_branch_noopt.rs:+1:11: +1:17
           StorageDead(_5);                 // scope 0 at $DIR/early_otherwise_branch_noopt.rs:+1:16: +1:17
           StorageDead(_4);                 // scope 0 at $DIR/early_otherwise_branch_noopt.rs:+1:16: +1:17
           _8 = discriminant((_3.0: std::option::Option<u32>)); // scope 0 at $DIR/early_otherwise_branch_noopt.rs:+1:11: +1:17
diff --git a/tests/mir-opt/enum_opt.cand.EnumSizeOpt.32bit.diff b/tests/mir-opt/enum_opt.cand.EnumSizeOpt.32bit.diff
new file mode 100644
index 000000000..b139deeee
--- /dev/null
+++ b/tests/mir-opt/enum_opt.cand.EnumSizeOpt.32bit.diff
@@ -0,0 +1,68 @@
+- // MIR for `cand` before EnumSizeOpt
++ // MIR for `cand` after EnumSizeOpt
+  
+  fn cand() -> Candidate {
+      let mut _0: Candidate;               // return place in scope 0 at $DIR/enum_opt.rs:+0:18: +0:27
+      let mut _1: Candidate;               // in scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+      let mut _2: Candidate;               // in scope 0 at $DIR/enum_opt.rs:+2:7: +2:34
+      let mut _3: [u8; 8196];              // in scope 0 at $DIR/enum_opt.rs:+2:24: +2:33
++     let mut _4: [usize; 2];              // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _5: isize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _6: usize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _7: usize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _8: *mut Candidate;          // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _9: *mut u8;                 // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _10: *const Candidate;       // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _11: *const u8;              // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _12: [usize; 2];             // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _13: isize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _14: usize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _15: usize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _16: *mut Candidate;         // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _17: *mut u8;                // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _18: *const Candidate;       // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _19: *const u8;              // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/enum_opt.rs:+1:7: +1:12
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+          _1 = Candidate::Small(const 1_u8); // scope 0 at $DIR/enum_opt.rs:+1:15: +1:34
+          StorageLive(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:7: +2:34
+          StorageLive(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:24: +2:33
+          _3 = [const 1_u8; 8196];         // scope 1 at $DIR/enum_opt.rs:+2:24: +2:33
+          _2 = Candidate::Large(move _3);  // scope 1 at $DIR/enum_opt.rs:+2:7: +2:34
+          StorageDead(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:33: +2:34
+-         _1 = move _2;                    // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         StorageLive(_4);                 // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _4 = const [2_usize, 8197_usize]; // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _5 = discriminant(_2);           // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _6 = _5 as usize (IntToInt);     // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _7 = _4[_6];                     // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _8 = &raw mut _1;                // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _9 = _8 as *mut u8 (PtrToPtr);   // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _10 = &raw const _2;             // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _11 = _10 as *const u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         Deinit(_8);                      // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         copy_nonoverlapping(dst = _9, src = _11, count = _7); // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         StorageDead(_4);                 // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
+          StorageDead(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:33: +2:34
+-         _0 = move _1;                    // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         StorageLive(_12);                // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _12 = const [2_usize, 8197_usize]; // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _13 = discriminant(_1);          // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _14 = _13 as usize (IntToInt);   // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _15 = _12[_14];                  // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _16 = &raw mut _0;               // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _17 = _16 as *mut u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _18 = &raw const _1;             // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _19 = _18 as *const u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         Deinit(_16);                     // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         copy_nonoverlapping(dst = _17, src = _19, count = _15); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         StorageDead(_12);                // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
+          StorageDead(_1);                 // scope 0 at $DIR/enum_opt.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/enum_opt.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/enum_opt.cand.EnumSizeOpt.64bit.diff b/tests/mir-opt/enum_opt.cand.EnumSizeOpt.64bit.diff
new file mode 100644
index 000000000..b139deeee
--- /dev/null
+++ b/tests/mir-opt/enum_opt.cand.EnumSizeOpt.64bit.diff
@@ -0,0 +1,68 @@
+- // MIR for `cand` before EnumSizeOpt
++ // MIR for `cand` after EnumSizeOpt
+  
+  fn cand() -> Candidate {
+      let mut _0: Candidate;               // return place in scope 0 at $DIR/enum_opt.rs:+0:18: +0:27
+      let mut _1: Candidate;               // in scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+      let mut _2: Candidate;               // in scope 0 at $DIR/enum_opt.rs:+2:7: +2:34
+      let mut _3: [u8; 8196];              // in scope 0 at $DIR/enum_opt.rs:+2:24: +2:33
++     let mut _4: [usize; 2];              // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _5: isize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _6: usize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _7: usize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _8: *mut Candidate;          // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _9: *mut u8;                 // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _10: *const Candidate;       // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _11: *const u8;              // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:34
++     let mut _12: [usize; 2];             // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _13: isize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _14: usize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _15: usize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _16: *mut Candidate;         // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _17: *mut u8;                // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _18: *const Candidate;       // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _19: *const u8;              // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/enum_opt.rs:+1:7: +1:12
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+          _1 = Candidate::Small(const 1_u8); // scope 0 at $DIR/enum_opt.rs:+1:15: +1:34
+          StorageLive(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:7: +2:34
+          StorageLive(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:24: +2:33
+          _3 = [const 1_u8; 8196];         // scope 1 at $DIR/enum_opt.rs:+2:24: +2:33
+          _2 = Candidate::Large(move _3);  // scope 1 at $DIR/enum_opt.rs:+2:7: +2:34
+          StorageDead(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:33: +2:34
+-         _1 = move _2;                    // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         StorageLive(_4);                 // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _4 = const [2_usize, 8197_usize]; // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _5 = discriminant(_2);           // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _6 = _5 as usize (IntToInt);     // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _7 = _4[_6];                     // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _8 = &raw mut _1;                // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _9 = _8 as *mut u8 (PtrToPtr);   // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _10 = &raw const _2;             // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         _11 = _10 as *const u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         Deinit(_8);                      // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         copy_nonoverlapping(dst = _9, src = _11, count = _7); // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
++         StorageDead(_4);                 // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
+          StorageDead(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:33: +2:34
+-         _0 = move _1;                    // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         StorageLive(_12);                // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _12 = const [2_usize, 8197_usize]; // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _13 = discriminant(_1);          // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _14 = _13 as usize (IntToInt);   // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _15 = _12[_14];                  // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _16 = &raw mut _0;               // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _17 = _16 as *mut u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _18 = &raw const _1;             // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _19 = _18 as *const u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         Deinit(_16);                     // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         copy_nonoverlapping(dst = _17, src = _19, count = _15); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         StorageDead(_12);                // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
+          StorageDead(_1);                 // scope 0 at $DIR/enum_opt.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/enum_opt.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/enum_opt.invalid.EnumSizeOpt.32bit.diff b/tests/mir-opt/enum_opt.invalid.EnumSizeOpt.32bit.diff
new file mode 100644
index 000000000..a80001149
--- /dev/null
+++ b/tests/mir-opt/enum_opt.invalid.EnumSizeOpt.32bit.diff
@@ -0,0 +1,28 @@
+- // MIR for `invalid` before EnumSizeOpt
++ // MIR for `invalid` after EnumSizeOpt
+  
+  fn invalid() -> InvalidIdxs {
+      let mut _0: InvalidIdxs;             // return place in scope 0 at $DIR/enum_opt.rs:+0:21: +0:32
+      let mut _1: InvalidIdxs;             // in scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+      let mut _2: InvalidIdxs;             // in scope 0 at $DIR/enum_opt.rs:+2:7: +2:36
+      let mut _3: [u64; 1024];             // in scope 0 at $DIR/enum_opt.rs:+2:26: +2:35
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/enum_opt.rs:+1:7: +1:12
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+          _1 = InvalidIdxs::A;             // scope 0 at $DIR/enum_opt.rs:+1:15: +1:29
+          StorageLive(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:7: +2:36
+          StorageLive(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:26: +2:35
+          _3 = [const 0_u64; 1024];        // scope 1 at $DIR/enum_opt.rs:+2:26: +2:35
+          _2 = InvalidIdxs::Large(move _3); // scope 1 at $DIR/enum_opt.rs:+2:7: +2:36
+          StorageDead(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:35: +2:36
+          _1 = move _2;                    // scope 1 at $DIR/enum_opt.rs:+2:3: +2:36
+          StorageDead(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:35: +2:36
+          _0 = move _1;                    // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
+          StorageDead(_1);                 // scope 0 at $DIR/enum_opt.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/enum_opt.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/enum_opt.invalid.EnumSizeOpt.64bit.diff b/tests/mir-opt/enum_opt.invalid.EnumSizeOpt.64bit.diff
new file mode 100644
index 000000000..a80001149
--- /dev/null
+++ b/tests/mir-opt/enum_opt.invalid.EnumSizeOpt.64bit.diff
@@ -0,0 +1,28 @@
+- // MIR for `invalid` before EnumSizeOpt
++ // MIR for `invalid` after EnumSizeOpt
+  
+  fn invalid() -> InvalidIdxs {
+      let mut _0: InvalidIdxs;             // return place in scope 0 at $DIR/enum_opt.rs:+0:21: +0:32
+      let mut _1: InvalidIdxs;             // in scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+      let mut _2: InvalidIdxs;             // in scope 0 at $DIR/enum_opt.rs:+2:7: +2:36
+      let mut _3: [u64; 1024];             // in scope 0 at $DIR/enum_opt.rs:+2:26: +2:35
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/enum_opt.rs:+1:7: +1:12
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+          _1 = InvalidIdxs::A;             // scope 0 at $DIR/enum_opt.rs:+1:15: +1:29
+          StorageLive(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:7: +2:36
+          StorageLive(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:26: +2:35
+          _3 = [const 0_u64; 1024];        // scope 1 at $DIR/enum_opt.rs:+2:26: +2:35
+          _2 = InvalidIdxs::Large(move _3); // scope 1 at $DIR/enum_opt.rs:+2:7: +2:36
+          StorageDead(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:35: +2:36
+          _1 = move _2;                    // scope 1 at $DIR/enum_opt.rs:+2:3: +2:36
+          StorageDead(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:35: +2:36
+          _0 = move _1;                    // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
+          StorageDead(_1);                 // scope 0 at $DIR/enum_opt.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/enum_opt.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/enum_opt.rs b/tests/mir-opt/enum_opt.rs
new file mode 100644
index 000000000..2768d7080
--- /dev/null
+++ b/tests/mir-opt/enum_opt.rs
@@ -0,0 +1,86 @@
+// unit-test: EnumSizeOpt
+// EMIT_MIR_FOR_EACH_BIT_WIDTH
+// compile-flags: -Zunsound-mir-opts
+
+#![feature(arbitrary_enum_discriminant, repr128)]
+
+// Tests that an enum with a variant with no data gets correctly transformed.
+pub enum NoData {
+  Large([u8; 8196]),
+  None,
+}
+
+// Tests that an enum with a variant with data that is a valid candidate gets transformed.
+pub enum Candidate {
+  Small(u8),
+  Large([u8; 8196]),
+}
+
+// Tests that an enum which has a discriminant much higher than the variant does not get
+// tformed.
+#[repr(u32)]
+pub enum InvalidIdxs {
+  A = 302,
+  Large([u64; 1024]),
+}
+
+// Tests that an enum with too high of a discriminant index (not in bounds of usize) does not
+// get tformed.
+#[repr(u128)]
+pub enum NotTrunctable {
+    A = 0,
+    B([u8; 1024]) = 1,
+    C([u8; 4096]) = 0x10000000000000001,
+}
+
+// Tests that an enum with discriminants in random order still gets tformed correctly.
+#[repr(u32)]
+pub enum RandOrderDiscr {
+  A = 13,
+  B([u8; 1024]) = 5,
+  C = 7,
+}
+
+// EMIT_MIR enum_opt.unin.EnumSizeOpt.diff
+pub fn unin() -> NoData {
+  let mut a = NoData::None;
+  a = NoData::Large([1; 8196]);
+  a
+}
+
+// EMIT_MIR enum_opt.cand.EnumSizeOpt.diff
+pub fn cand() -> Candidate {
+  let mut a = Candidate::Small(1);
+  a = Candidate::Large([1; 8196]);
+  a
+}
+
+// EMIT_MIR enum_opt.invalid.EnumSizeOpt.diff
+pub fn invalid() -> InvalidIdxs {
+  let mut a = InvalidIdxs::A;
+  a = InvalidIdxs::Large([0; 1024]);
+  a
+}
+
+// EMIT_MIR enum_opt.trunc.EnumSizeOpt.diff
+pub fn trunc() -> NotTrunctable {
+  let mut a = NotTrunctable::A;
+  a = NotTrunctable::B([0; 1024]);
+  a = NotTrunctable::C([0; 4096]);
+  a
+}
+
+pub fn rand_order() -> RandOrderDiscr {
+  let mut a = RandOrderDiscr::A;
+  a = RandOrderDiscr::B([0; 1024]);
+  a = RandOrderDiscr::C;
+  a
+}
+
+pub fn main() {
+  unin();
+  cand();
+  invalid();
+  trunc();
+  rand_order();
+}
diff --git a/tests/mir-opt/enum_opt.trunc.EnumSizeOpt.32bit.diff b/tests/mir-opt/enum_opt.trunc.EnumSizeOpt.32bit.diff
new file mode 100644
index 000000000..1ef79044d
--- /dev/null
+++ b/tests/mir-opt/enum_opt.trunc.EnumSizeOpt.32bit.diff
@@ -0,0 +1,37 @@
+- // MIR for `trunc` before EnumSizeOpt
++ // MIR for `trunc` after EnumSizeOpt
+  
+  fn trunc() -> NotTrunctable {
+      let mut _0: NotTrunctable;           // return place in scope 0 at $DIR/enum_opt.rs:+0:19: +0:32
+      let mut _1: NotTrunctable;           // in scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+      let mut _2: NotTrunctable;           // in scope 0 at $DIR/enum_opt.rs:+2:7: +2:34
+      let mut _3: [u8; 1024];              // in scope 0 at $DIR/enum_opt.rs:+2:24: +2:33
+      let mut _4: NotTrunctable;           // in scope 0 at $DIR/enum_opt.rs:+3:7: +3:34
+      let mut _5: [u8; 4096];              // in scope 0 at $DIR/enum_opt.rs:+3:24: +3:33
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/enum_opt.rs:+1:7: +1:12
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+          _1 = NotTrunctable::A;           // scope 0 at $DIR/enum_opt.rs:+1:15: +1:31
+          StorageLive(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:7: +2:34
+          StorageLive(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:24: +2:33
+          _3 = [const 0_u8; 1024];         // scope 1 at $DIR/enum_opt.rs:+2:24: +2:33
+          _2 = NotTrunctable::B(move _3);  // scope 1 at $DIR/enum_opt.rs:+2:7: +2:34
+          StorageDead(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:33: +2:34
+          _1 = move _2;                    // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
+          StorageDead(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:33: +2:34
+          StorageLive(_4);                 // scope 1 at $DIR/enum_opt.rs:+3:7: +3:34
+          StorageLive(_5);                 // scope 1 at $DIR/enum_opt.rs:+3:24: +3:33
+          _5 = [const 0_u8; 4096];         // scope 1 at $DIR/enum_opt.rs:+3:24: +3:33
+          _4 = NotTrunctable::C(move _5);  // scope 1 at $DIR/enum_opt.rs:+3:7: +3:34
+          StorageDead(_5);                 // scope 1 at $DIR/enum_opt.rs:+3:33: +3:34
+          _1 = move _4;                    // scope 1 at $DIR/enum_opt.rs:+3:3: +3:34
+          StorageDead(_4);                 // scope 1 at $DIR/enum_opt.rs:+3:33: +3:34
+          _0 = move _1;                    // scope 1 at $DIR/enum_opt.rs:+4:3: +4:4
+          StorageDead(_1);                 // scope 0 at $DIR/enum_opt.rs:+5:1: +5:2
+          return;                          // scope 0 at $DIR/enum_opt.rs:+5:2: +5:2
+      }
+  }
+  
diff --git a/tests/mir-opt/enum_opt.trunc.EnumSizeOpt.64bit.diff b/tests/mir-opt/enum_opt.trunc.EnumSizeOpt.64bit.diff
new file mode 100644
index 000000000..1ef79044d
--- /dev/null
+++ b/tests/mir-opt/enum_opt.trunc.EnumSizeOpt.64bit.diff
@@ -0,0 +1,37 @@
+- // MIR for `trunc` before EnumSizeOpt
++ // MIR for `trunc` after EnumSizeOpt
+  
+  fn trunc() -> NotTrunctable {
+      let mut _0: NotTrunctable;           // return place in scope 0 at $DIR/enum_opt.rs:+0:19: +0:32
+      let mut _1: NotTrunctable;           // in scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+      let mut _2: NotTrunctable;           // in scope 0 at $DIR/enum_opt.rs:+2:7: +2:34
+      let mut _3: [u8; 1024];              // in scope 0 at $DIR/enum_opt.rs:+2:24: +2:33
+      let mut _4: NotTrunctable;           // in scope 0 at $DIR/enum_opt.rs:+3:7: +3:34
+      let mut _5: [u8; 4096];              // in scope 0 at $DIR/enum_opt.rs:+3:24: +3:33
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/enum_opt.rs:+1:7: +1:12
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+          _1 = NotTrunctable::A;           // scope 0 at $DIR/enum_opt.rs:+1:15: +1:31
+          StorageLive(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:7: +2:34
+          StorageLive(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:24: +2:33
+          _3 = [const 0_u8; 1024];         // scope 1 at $DIR/enum_opt.rs:+2:24: +2:33
+          _2 = NotTrunctable::B(move _3);  // scope 1 at $DIR/enum_opt.rs:+2:7: +2:34
+          StorageDead(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:33: +2:34
+          _1 = move _2;                    // scope 1 at $DIR/enum_opt.rs:+2:3: +2:34
+          StorageDead(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:33: +2:34
+          StorageLive(_4);                 // scope 1 at $DIR/enum_opt.rs:+3:7: +3:34
+          StorageLive(_5);                 // scope 1 at $DIR/enum_opt.rs:+3:24: +3:33
+          _5 = [const 0_u8; 4096];         // scope 1 at $DIR/enum_opt.rs:+3:24: +3:33
+          _4 = NotTrunctable::C(move _5);  // scope 1 at $DIR/enum_opt.rs:+3:7: +3:34
+          StorageDead(_5);                 // scope 1 at $DIR/enum_opt.rs:+3:33: +3:34
+          _1 = move _4;                    // scope 1 at $DIR/enum_opt.rs:+3:3: +3:34
+          StorageDead(_4);                 // scope 1 at $DIR/enum_opt.rs:+3:33: +3:34
+          _0 = move _1;                    // scope 1 at $DIR/enum_opt.rs:+4:3: +4:4
+          StorageDead(_1);                 // scope 0 at $DIR/enum_opt.rs:+5:1: +5:2
+          return;                          // scope 0 at $DIR/enum_opt.rs:+5:2: +5:2
+      }
+  }
+  
diff --git a/tests/mir-opt/enum_opt.unin.EnumSizeOpt.32bit.diff b/tests/mir-opt/enum_opt.unin.EnumSizeOpt.32bit.diff
new file mode 100644
index 000000000..ad9f12cf9
--- /dev/null
+++ b/tests/mir-opt/enum_opt.unin.EnumSizeOpt.32bit.diff
@@ -0,0 +1,68 @@
+- // MIR for `unin` before EnumSizeOpt
++ // MIR for `unin` after EnumSizeOpt
+  
+  fn unin() -> NoData {
+      let mut _0: NoData;                  // return place in scope 0 at $DIR/enum_opt.rs:+0:18: +0:24
+      let mut _1: NoData;                  // in scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+      let mut _2: NoData;                  // in scope 0 at $DIR/enum_opt.rs:+2:7: +2:31
+      let mut _3: [u8; 8196];              // in scope 0 at $DIR/enum_opt.rs:+2:21: +2:30
++     let mut _4: [usize; 2];              // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _5: isize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _6: usize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _7: usize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _8: *mut NoData;             // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _9: *mut u8;                 // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _10: *const NoData;          // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _11: *const u8;              // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _12: [usize; 2];             // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _13: isize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _14: usize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _15: usize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _16: *mut NoData;            // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _17: *mut u8;                // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _18: *const NoData;          // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _19: *const u8;              // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/enum_opt.rs:+1:7: +1:12
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+          _1 = NoData::None;               // scope 0 at $DIR/enum_opt.rs:+1:15: +1:27
+          StorageLive(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:7: +2:31
+          StorageLive(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:21: +2:30
+          _3 = [const 1_u8; 8196];         // scope 1 at $DIR/enum_opt.rs:+2:21: +2:30
+          _2 = NoData::Large(move _3);     // scope 1 at $DIR/enum_opt.rs:+2:7: +2:31
+          StorageDead(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:30: +2:31
+-         _1 = move _2;                    // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         StorageLive(_4);                 // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _4 = const [8197_usize, 1_usize]; // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _5 = discriminant(_2);           // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _6 = _5 as usize (IntToInt);     // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _7 = _4[_6];                     // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _8 = &raw mut _1;                // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _9 = _8 as *mut u8 (PtrToPtr);   // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _10 = &raw const _2;             // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _11 = _10 as *const u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         Deinit(_8);                      // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         copy_nonoverlapping(dst = _9, src = _11, count = _7); // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         StorageDead(_4);                 // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
+          StorageDead(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:30: +2:31
+-         _0 = move _1;                    // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         StorageLive(_12);                // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _12 = const [8197_usize, 1_usize]; // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _13 = discriminant(_1);          // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _14 = _13 as usize (IntToInt);   // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _15 = _12[_14];                  // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _16 = &raw mut _0;               // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _17 = _16 as *mut u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _18 = &raw const _1;             // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _19 = _18 as *const u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         Deinit(_16);                     // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         copy_nonoverlapping(dst = _17, src = _19, count = _15); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         StorageDead(_12);                // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
+          StorageDead(_1);                 // scope 0 at $DIR/enum_opt.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/enum_opt.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/enum_opt.unin.EnumSizeOpt.64bit.diff b/tests/mir-opt/enum_opt.unin.EnumSizeOpt.64bit.diff
new file mode 100644
index 000000000..ad9f12cf9
--- /dev/null
+++ b/tests/mir-opt/enum_opt.unin.EnumSizeOpt.64bit.diff
@@ -0,0 +1,68 @@
+- // MIR for `unin` before EnumSizeOpt
++ // MIR for `unin` after EnumSizeOpt
+  
+  fn unin() -> NoData {
+      let mut _0: NoData;                  // return place in scope 0 at $DIR/enum_opt.rs:+0:18: +0:24
+      let mut _1: NoData;                  // in scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+      let mut _2: NoData;                  // in scope 0 at $DIR/enum_opt.rs:+2:7: +2:31
+      let mut _3: [u8; 8196];              // in scope 0 at $DIR/enum_opt.rs:+2:21: +2:30
++     let mut _4: [usize; 2];              // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _5: isize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _6: usize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _7: usize;                   // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _8: *mut NoData;             // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _9: *mut u8;                 // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _10: *const NoData;          // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _11: *const u8;              // in scope 0 at $DIR/enum_opt.rs:+2:3: +2:31
++     let mut _12: [usize; 2];             // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _13: isize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _14: usize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _15: usize;                  // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _16: *mut NoData;            // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _17: *mut u8;                // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _18: *const NoData;          // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
++     let mut _19: *const u8;              // in scope 0 at $DIR/enum_opt.rs:+3:3: +3:4
+      scope 1 {
+          debug a => _1;                   // in scope 1 at $DIR/enum_opt.rs:+1:7: +1:12
+      }
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/enum_opt.rs:+1:7: +1:12
+          _1 = NoData::None;               // scope 0 at $DIR/enum_opt.rs:+1:15: +1:27
+          StorageLive(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:7: +2:31
+          StorageLive(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:21: +2:30
+          _3 = [const 1_u8; 8196];         // scope 1 at $DIR/enum_opt.rs:+2:21: +2:30
+          _2 = NoData::Large(move _3);     // scope 1 at $DIR/enum_opt.rs:+2:7: +2:31
+          StorageDead(_3);                 // scope 1 at $DIR/enum_opt.rs:+2:30: +2:31
+-         _1 = move _2;                    // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         StorageLive(_4);                 // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _4 = const [8197_usize, 1_usize]; // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _5 = discriminant(_2);           // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _6 = _5 as usize (IntToInt);     // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _7 = _4[_6];                     // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _8 = &raw mut _1;                // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _9 = _8 as *mut u8 (PtrToPtr);   // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _10 = &raw const _2;             // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         _11 = _10 as *const u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         Deinit(_8);                      // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         copy_nonoverlapping(dst = _9, src = _11, count = _7); // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
++         StorageDead(_4);                 // scope 1 at $DIR/enum_opt.rs:+2:3: +2:31
+          StorageDead(_2);                 // scope 1 at $DIR/enum_opt.rs:+2:30: +2:31
+-         _0 = move _1;                    // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         StorageLive(_12);                // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _12 = const [8197_usize, 1_usize]; // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _13 = discriminant(_1);          // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _14 = _13 as usize (IntToInt);   // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _15 = _12[_14];                  // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _16 = &raw mut _0;               // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _17 = _16 as *mut u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _18 = &raw const _1;             // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         _19 = _18 as *const u8 (PtrToPtr); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         Deinit(_16);                     // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         copy_nonoverlapping(dst = _17, src = _19, count = _15); // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
++         StorageDead(_12);                // scope 1 at $DIR/enum_opt.rs:+3:3: +3:4
+          StorageDead(_1);                 // scope 0 at $DIR/enum_opt.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/enum_opt.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/funky_arms.float_to_exponential_common.ConstProp.diff b/tests/mir-opt/funky_arms.float_to_exponential_common.ConstProp.diff
index c1c2cde71..1f5c53381 100644
--- a/tests/mir-opt/funky_arms.float_to_exponential_common.ConstProp.diff
+++ b/tests/mir-opt/funky_arms.float_to_exponential_common.ConstProp.diff
@@ -51,14 +51,20 @@
       }
   
       bb2: {
-          Deinit(_6);                      // scope 1 at $DIR/funky_arms.rs:+10:17: +10:41
-          discriminant(_6) = 1;            // scope 1 at $DIR/funky_arms.rs:+10:17: +10:41
+-         _6 = MinusPlus;                  // scope 1 at $DIR/funky_arms.rs:+10:17: +10:41
++         _6 = const MinusPlus;            // scope 1 at $DIR/funky_arms.rs:+10:17: +10:41
++                                          // mir::Constant
++                                          // + span: $DIR/funky_arms.rs:21:17: 21:41
++                                          // + literal: Const { ty: Sign, val: Value(Scalar(0x01)) }
           goto -> bb4;                     // scope 1 at $DIR/funky_arms.rs:+10:17: +10:41
       }
   
       bb3: {
-          Deinit(_6);                      // scope 1 at $DIR/funky_arms.rs:+9:18: +9:38
-          discriminant(_6) = 0;            // scope 1 at $DIR/funky_arms.rs:+9:18: +9:38
+-         _6 = Minus;                      // scope 1 at $DIR/funky_arms.rs:+9:18: +9:38
++         _6 = const Minus;                // scope 1 at $DIR/funky_arms.rs:+9:18: +9:38
++                                          // mir::Constant
++                                          // + span: $DIR/funky_arms.rs:20:18: 20:38
++                                          // + literal: Const { ty: Sign, val: Value(Scalar(0x00)) }
           goto -> bb4;                     // scope 1 at $DIR/funky_arms.rs:+9:18: +9:38
       }
   
@@ -79,60 +85,37 @@
       }
   
       bb6: {
-          StorageLive(_10);                // scope 3 at $DIR/funky_arms.rs:+13:17: +13:26
           _10 = ((_7 as Some).0: usize);   // scope 3 at $DIR/funky_arms.rs:+13:17: +13:26
-          StorageLive(_11);                // scope 3 at $DIR/funky_arms.rs:+15:43: +15:46
-          _11 = &mut (*_1);                // scope 3 at $DIR/funky_arms.rs:+15:43: +15:46
-          StorageLive(_12);                // scope 3 at $DIR/funky_arms.rs:+15:48: +15:51
-          _12 = _2;                        // scope 3 at $DIR/funky_arms.rs:+15:48: +15:51
           StorageLive(_13);                // scope 3 at $DIR/funky_arms.rs:+15:53: +15:57
           _13 = _6;                        // scope 3 at $DIR/funky_arms.rs:+15:53: +15:57
           StorageLive(_14);                // scope 3 at $DIR/funky_arms.rs:+15:59: +15:79
           StorageLive(_15);                // scope 3 at $DIR/funky_arms.rs:+15:59: +15:75
-          StorageLive(_16);                // scope 3 at $DIR/funky_arms.rs:+15:59: +15:68
-          _16 = _10;                       // scope 3 at $DIR/funky_arms.rs:+15:59: +15:68
-          _15 = move _16 as u32 (IntToInt); // scope 3 at $DIR/funky_arms.rs:+15:59: +15:75
-          StorageDead(_16);                // scope 3 at $DIR/funky_arms.rs:+15:74: +15:75
+          _15 = _10 as u32 (IntToInt);     // scope 3 at $DIR/funky_arms.rs:+15:59: +15:75
           _14 = Add(move _15, const 1_u32); // scope 3 at $DIR/funky_arms.rs:+15:59: +15:79
           StorageDead(_15);                // scope 3 at $DIR/funky_arms.rs:+15:78: +15:79
-          StorageLive(_17);                // scope 3 at $DIR/funky_arms.rs:+15:81: +15:86
-          _17 = _3;                        // scope 3 at $DIR/funky_arms.rs:+15:81: +15:86
-          _0 = float_to_exponential_common_exact::<T>(move _11, move _12, move _13, move _14, move _17) -> bb7; // scope 3 at $DIR/funky_arms.rs:+15:9: +15:87
+          _0 = float_to_exponential_common_exact::<T>(_1, _2, move _13, move _14, _3) -> bb7; // scope 3 at $DIR/funky_arms.rs:+15:9: +15:87
                                            // mir::Constant
                                            // + span: $DIR/funky_arms.rs:26:9: 26:42
                                            // + literal: Const { ty: for<'a, 'b, 'c> fn(&'a mut Formatter<'b>, &'c T, Sign, u32, bool) -> Result<(), std::fmt::Error> {float_to_exponential_common_exact::<T>}, val: Value(<ZST>) }
       }
   
       bb7: {
-          StorageDead(_17);                // scope 3 at $DIR/funky_arms.rs:+15:86: +15:87
           StorageDead(_14);                // scope 3 at $DIR/funky_arms.rs:+15:86: +15:87
           StorageDead(_13);                // scope 3 at $DIR/funky_arms.rs:+15:86: +15:87
-          StorageDead(_12);                // scope 3 at $DIR/funky_arms.rs:+15:86: +15:87
-          StorageDead(_11);                // scope 3 at $DIR/funky_arms.rs:+15:86: +15:87
-          StorageDead(_10);                // scope 2 at $DIR/funky_arms.rs:+16:5: +16:6
           goto -> bb10;                    // scope 2 at $DIR/funky_arms.rs:+13:5: +18:6
       }
   
       bb8: {
-          StorageLive(_18);                // scope 2 at $DIR/funky_arms.rs:+17:46: +17:49
-          _18 = &mut (*_1);                // scope 2 at $DIR/funky_arms.rs:+17:46: +17:49
-          StorageLive(_19);                // scope 2 at $DIR/funky_arms.rs:+17:51: +17:54
-          _19 = _2;                        // scope 2 at $DIR/funky_arms.rs:+17:51: +17:54
           StorageLive(_20);                // scope 2 at $DIR/funky_arms.rs:+17:56: +17:60
           _20 = _6;                        // scope 2 at $DIR/funky_arms.rs:+17:56: +17:60
-          StorageLive(_21);                // scope 2 at $DIR/funky_arms.rs:+17:62: +17:67
-          _21 = _3;                        // scope 2 at $DIR/funky_arms.rs:+17:62: +17:67
-          _0 = float_to_exponential_common_shortest::<T>(move _18, move _19, move _20, move _21) -> bb9; // scope 2 at $DIR/funky_arms.rs:+17:9: +17:68
+          _0 = float_to_exponential_common_shortest::<T>(_1, _2, move _20, _3) -> bb9; // scope 2 at $DIR/funky_arms.rs:+17:9: +17:68
                                            // mir::Constant
                                            // + span: $DIR/funky_arms.rs:28:9: 28:45
                                            // + literal: Const { ty: for<'a, 'b, 'c> fn(&'a mut Formatter<'b>, &'c T, Sign, bool) -> Result<(), std::fmt::Error> {float_to_exponential_common_shortest::<T>}, val: Value(<ZST>) }
       }
   
       bb9: {
-          StorageDead(_21);                // scope 2 at $DIR/funky_arms.rs:+17:67: +17:68
           StorageDead(_20);                // scope 2 at $DIR/funky_arms.rs:+17:67: +17:68
-          StorageDead(_19);                // scope 2 at $DIR/funky_arms.rs:+17:67: +17:68
-          StorageDead(_18);                // scope 2 at $DIR/funky_arms.rs:+17:67: +17:68
           goto -> bb10;                    // scope 2 at $DIR/funky_arms.rs:+13:5: +18:6
       }
   
diff --git a/tests/mir-opt/generator_drop_cleanup.main-{closure#0}.generator_drop.0.mir b/tests/mir-opt/generator_drop_cleanup.main-{closure#0}.generator_drop.0.mir
index a8e090020..afe518642 100644
--- a/tests/mir-opt/generator_drop_cleanup.main-{closure#0}.generator_drop.0.mir
+++ b/tests/mir-opt/generator_drop_cleanup.main-{closure#0}.generator_drop.0.mir
@@ -1,7 +1,14 @@
 // MIR for `main::{closure#0}` 0 generator_drop
 /* generator_layout = GeneratorLayout {
     field_tys: {
-        _0: std::string::String,
+        _0: GeneratorSavedTy {
+            ty: std::string::String,
+            source_info: SourceInfo {
+                span: $DIR/generator_drop_cleanup.rs:11:13: 11:15 (#0),
+                scope: scope[0],
+            },
+            ignore_for_traits: false,
+        },
     },
     variant_fields: {
         Unresumed(0): [],
diff --git a/tests/mir-opt/generator_tiny.main-{closure#0}.generator_resume.0.mir b/tests/mir-opt/generator_tiny.main-{closure#0}.generator_resume.0.mir
index b3d3c768a..7efda05d2 100644
--- a/tests/mir-opt/generator_tiny.main-{closure#0}.generator_resume.0.mir
+++ b/tests/mir-opt/generator_tiny.main-{closure#0}.generator_resume.0.mir
@@ -1,7 +1,14 @@
 // MIR for `main::{closure#0}` 0 generator_resume
 /* generator_layout = GeneratorLayout {
     field_tys: {
-        _0: HasDrop,
+        _0: GeneratorSavedTy {
+            ty: HasDrop,
+            source_info: SourceInfo {
+                span: $DIR/generator_tiny.rs:20:13: 20:15 (#0),
+                scope: scope[0],
+            },
+            ignore_for_traits: false,
+        },
     },
     variant_fields: {
         Unresumed(0): [],
@@ -47,9 +54,7 @@ fn main::{closure#0}(_1: Pin<&mut [generator@$DIR/generator_tiny.rs:19:16: 19:24
         StorageLive(_6);                 // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
         StorageLive(_7);                 // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
         _7 = ();                         // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
-        Deinit(_0);                      // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
-        ((_0 as Yielded).0: ()) = move _7; // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
-        discriminant(_0) = 0;            // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
+        _0 = GeneratorState::<(), ()>::Yielded(move _7); // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
         discriminant((*(_1.0: &mut [generator@$DIR/generator_tiny.rs:19:16: 19:24]))) = 3; // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
         return;                          // scope 1 at $DIR/generator_tiny.rs:+3:13: +3:18
     }
diff --git a/tests/mir-opt/inline/cycle.f.Inline.diff b/tests/mir-opt/inline/cycle.f.Inline.diff
index 75ea69a42..501390c3b 100644
--- a/tests/mir-opt/inline/cycle.f.Inline.diff
+++ b/tests/mir-opt/inline/cycle.f.Inline.diff
@@ -13,7 +13,7 @@
           StorageLive(_3);                 // scope 0 at $DIR/cycle.rs:+1:5: +1:6
           _3 = &_1;                        // scope 0 at $DIR/cycle.rs:+1:5: +1:6
           StorageLive(_4);                 // scope 0 at $DIR/cycle.rs:+1:5: +1:8
-          Deinit(_4);                      // scope 0 at $DIR/cycle.rs:+1:5: +1:8
+          _4 = ();                         // scope 0 at $DIR/cycle.rs:+1:5: +1:8
           _2 = <impl Fn() as Fn<()>>::call(move _3, move _4) -> [return: bb1, unwind: bb3]; // scope 0 at $DIR/cycle.rs:+1:5: +1:8
                                            // mir::Constant
                                            // + span: $DIR/cycle.rs:6:5: 6:6
diff --git a/tests/mir-opt/inline/dyn_trait.get_query.Inline.diff b/tests/mir-opt/inline/dyn_trait.get_query.Inline.diff
index 8ea1a0757..64c3e47ff 100644
--- a/tests/mir-opt/inline/dyn_trait.get_query.Inline.diff
+++ b/tests/mir-opt/inline/dyn_trait.get_query.Inline.diff
@@ -35,8 +35,8 @@
           _4 = &(*_2);                     // scope 1 at $DIR/dyn_trait.rs:+2:23: +2:24
 -         _0 = try_execute_query::<<Q as Query>::C>(move _4) -> bb2; // scope 1 at $DIR/dyn_trait.rs:+2:5: +2:25
 +         StorageLive(_5);                 // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
-+         _5 = move _4 as &dyn Cache<V = <Q as Query>::V> (Pointer(Unsize)); // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
-+         _0 = <dyn Cache<V = <Q as Query>::V> as Cache>::store_nocache(move _5) -> bb2; // scope 3 at $DIR/dyn_trait.rs:21:5: 21:22
++         _5 = _4 as &dyn Cache<V = <Q as Query>::V> (Pointer(Unsize)); // scope 2 at $DIR/dyn_trait.rs:27:14: 27:15
++         _0 = <dyn Cache<V = <Q as Query>::V> as Cache>::store_nocache(_5) -> bb2; // scope 3 at $DIR/dyn_trait.rs:21:5: 21:22
                                            // mir::Constant
 -                                          // + span: $DIR/dyn_trait.rs:34:5: 34:22
 -                                          // + literal: Const { ty: for<'a> fn(&'a <Q as Query>::C) {try_execute_query::<<Q as Query>::C>}, val: Value(<ZST>) }
diff --git a/tests/mir-opt/inline/dyn_trait.try_execute_query.Inline.diff b/tests/mir-opt/inline/dyn_trait.try_execute_query.Inline.diff
index a71d73b74..3fa9c3e88 100644
--- a/tests/mir-opt/inline/dyn_trait.try_execute_query.Inline.diff
+++ b/tests/mir-opt/inline/dyn_trait.try_execute_query.Inline.diff
@@ -17,7 +17,7 @@
           _2 = move _3 as &dyn Cache<V = <C as Cache>::V> (Pointer(Unsize)); // scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
           StorageDead(_3);                 // scope 0 at $DIR/dyn_trait.rs:+1:14: +1:15
 -         _0 = mk_cycle::<<C as Cache>::V>(move _2) -> bb1; // scope 0 at $DIR/dyn_trait.rs:+1:5: +1:16
-+         _0 = <dyn Cache<V = <C as Cache>::V> as Cache>::store_nocache(move _2) -> bb1; // scope 1 at $DIR/dyn_trait.rs:21:5: 21:22
++         _0 = <dyn Cache<V = <C as Cache>::V> as Cache>::store_nocache(_2) -> bb1; // scope 1 at $DIR/dyn_trait.rs:21:5: 21:22
                                            // mir::Constant
 -                                          // + span: $DIR/dyn_trait.rs:27:5: 27:13
 -                                          // + literal: Const { ty: for<'a> fn(&'a (dyn Cache<V = <C as Cache>::V> + 'a)) {mk_cycle::<<C as Cache>::V>}, val: Value(<ZST>) }
diff --git a/tests/mir-opt/inline/inline_any_operand.bar.Inline.after.mir b/tests/mir-opt/inline/inline_any_operand.bar.Inline.after.mir
index 3502c2586..20f737cc2 100644
--- a/tests/mir-opt/inline/inline_any_operand.bar.Inline.after.mir
+++ b/tests/mir-opt/inline/inline_any_operand.bar.Inline.after.mir
@@ -26,7 +26,7 @@ fn bar() -> bool {
         _3 = const 1_i32;                // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
         StorageLive(_4);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
         _4 = const -1_i32;               // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
-        _0 = Eq(move _3, move _4);       // scope 2 at $DIR/inline_any_operand.rs:17:5: 17:11
+        _0 = Eq(_3, _4);                 // scope 2 at $DIR/inline_any_operand.rs:17:5: 17:11
         StorageDead(_4);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
         StorageDead(_3);                 // scope 1 at $DIR/inline_any_operand.rs:+2:5: +2:13
         StorageDead(_2);                 // scope 1 at $DIR/inline_any_operand.rs:+2:12: +2:13
diff --git a/tests/mir-opt/inline/inline_closure.foo.Inline.after.mir b/tests/mir-opt/inline/inline_closure.foo.Inline.after.mir
index 9eb3a01ee..fff8d0171 100644
--- a/tests/mir-opt/inline/inline_closure.foo.Inline.after.mir
+++ b/tests/mir-opt/inline/inline_closure.foo.Inline.after.mir
@@ -21,7 +21,15 @@ fn foo(_1: T, _2: i32) -> i32 {
 
     bb0: {
         StorageLive(_3);                 // scope 0 at $DIR/inline_closure.rs:+1:9: +1:10
-        Deinit(_3);                      // scope 0 at $DIR/inline_closure.rs:+1:13: +1:24
+        _3 = [closure@foo::<T>::{closure#0}]; // scope 0 at $DIR/inline_closure.rs:+1:13: +1:24
+                                         // closure
+                                         // + def_id: DefId(0:6 ~ inline_closure[92ba]::foo::{closure#0})
+                                         // + substs: [
+                                         //     T,
+                                         //     i8,
+                                         //     extern "rust-call" fn((i32, i32)) -> i32,
+                                         //     (),
+                                         // ]
         StorageLive(_4);                 // scope 1 at $DIR/inline_closure.rs:+2:5: +2:6
         _4 = &_3;                        // scope 1 at $DIR/inline_closure.rs:+2:5: +2:6
         StorageLive(_5);                 // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
@@ -29,9 +37,7 @@ fn foo(_1: T, _2: i32) -> i32 {
         _6 = _2;                         // scope 1 at $DIR/inline_closure.rs:+2:7: +2:8
         StorageLive(_7);                 // scope 1 at $DIR/inline_closure.rs:+2:10: +2:11
         _7 = _2;                         // scope 1 at $DIR/inline_closure.rs:+2:10: +2:11
-        Deinit(_5);                      // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
-        (_5.0: i32) = move _6;           // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
-        (_5.1: i32) = move _7;           // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
+        _5 = (move _6, move _7);         // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
         StorageLive(_8);                 // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
         _8 = move (_5.0: i32);           // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
         StorageLive(_9);                 // scope 1 at $DIR/inline_closure.rs:+2:5: +2:12
diff --git a/tests/mir-opt/inline/inline_closure_borrows_arg.foo.Inline.after.mir b/tests/mir-opt/inline/inline_closure_borrows_arg.foo.Inline.after.mir
index dd32eb2d8..dab204306 100644
--- a/tests/mir-opt/inline/inline_closure_borrows_arg.foo.Inline.after.mir
+++ b/tests/mir-opt/inline/inline_closure_borrows_arg.foo.Inline.after.mir
@@ -24,7 +24,15 @@ fn foo(_1: T, _2: &i32) -> i32 {
 
     bb0: {
         StorageLive(_3);                 // scope 0 at $DIR/inline_closure_borrows_arg.rs:+1:9: +1:10
-        Deinit(_3);                      // scope 0 at $DIR/inline_closure_borrows_arg.rs:+1:13: +4:6
+        _3 = [closure@foo::<T>::{closure#0}]; // scope 0 at $DIR/inline_closure_borrows_arg.rs:+1:13: +4:6
+                                         // closure
+                                         // + def_id: DefId(0:6 ~ inline_closure_borrows_arg[96e9]::foo::{closure#0})
+                                         // + substs: [
+                                         //     T,
+                                         //     i8,
+                                         //     for<'a, 'b> extern "rust-call" fn((&'a i32, &'b i32)) -> i32,
+                                         //     (),
+                                         // ]
         StorageLive(_4);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:6
         _4 = &_3;                        // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:6
         StorageLive(_5);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
@@ -32,9 +40,7 @@ fn foo(_1: T, _2: &i32) -> i32 {
         _6 = &(*_2);                     // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:7: +5:8
         StorageLive(_7);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:10: +5:11
         _7 = &(*_2);                     // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:10: +5:11
-        Deinit(_5);                      // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
-        (_5.0: &i32) = move _6;          // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
-        (_5.1: &i32) = move _7;          // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
+        _5 = (move _6, move _7);         // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
         StorageLive(_8);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
         _8 = move (_5.0: &i32);          // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
         StorageLive(_9);                 // scope 1 at $DIR/inline_closure_borrows_arg.rs:+5:5: +5:12
diff --git a/tests/mir-opt/inline/inline_closure_captures.foo.Inline.after.mir b/tests/mir-opt/inline/inline_closure_captures.foo.Inline.after.mir
index fd19c2886..84fd051e0 100644
--- a/tests/mir-opt/inline/inline_closure_captures.foo.Inline.after.mir
+++ b/tests/mir-opt/inline/inline_closure_captures.foo.Inline.after.mir
@@ -30,9 +30,15 @@ fn foo(_1: T, _2: i32) -> (i32, T) {
         _4 = &_2;                        // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
         StorageLive(_5);                 // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
         _5 = &_1;                        // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
-        Deinit(_3);                      // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
-        (_3.0: &i32) = move _4;          // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
-        (_3.1: &T) = move _5;            // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+        _3 = [closure@foo::<T>::{closure#0}] { q: move _4, t: move _5 }; // scope 0 at $DIR/inline_closure_captures.rs:+1:13: +1:24
+                                         // closure
+                                         // + def_id: DefId(0:6 ~ inline_closure_captures[8bc0]::foo::{closure#0})
+                                         // + substs: [
+                                         //     T,
+                                         //     i8,
+                                         //     extern "rust-call" fn((i32,)) -> (i32, T),
+                                         //     (&i32, &T),
+                                         // ]
         StorageDead(_5);                 // scope 0 at $DIR/inline_closure_captures.rs:+1:16: +1:17
         StorageDead(_4);                 // scope 0 at $DIR/inline_closure_captures.rs:+1:16: +1:17
         StorageLive(_6);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:6
@@ -40,8 +46,7 @@ fn foo(_1: T, _2: i32) -> (i32, T) {
         StorageLive(_7);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
         StorageLive(_8);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:7: +2:8
         _8 = _2;                         // scope 1 at $DIR/inline_closure_captures.rs:+2:7: +2:8
-        Deinit(_7);                      // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
-        (_7.0: i32) = move _8;           // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
+        _7 = (move _8,);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
         StorageLive(_9);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
         _9 = move (_7.0: i32);           // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
         StorageLive(_10);                // scope 2 at $DIR/inline_closure_captures.rs:+1:19: +1:20
@@ -50,9 +55,7 @@ fn foo(_1: T, _2: i32) -> (i32, T) {
         StorageLive(_11);                // scope 2 at $DIR/inline_closure_captures.rs:+1:22: +1:23
         _13 = deref_copy ((*_6).1: &T);  // scope 2 at $DIR/inline_closure_captures.rs:+1:22: +1:23
         _11 = (*_13);                    // scope 2 at $DIR/inline_closure_captures.rs:+1:22: +1:23
-        Deinit(_0);                      // scope 2 at $DIR/inline_closure_captures.rs:+1:18: +1:24
-        (_0.0: i32) = move _10;          // scope 2 at $DIR/inline_closure_captures.rs:+1:18: +1:24
-        (_0.1: T) = move _11;            // scope 2 at $DIR/inline_closure_captures.rs:+1:18: +1:24
+        _0 = (move _10, move _11);       // scope 2 at $DIR/inline_closure_captures.rs:+1:18: +1:24
         StorageDead(_11);                // scope 2 at $DIR/inline_closure_captures.rs:+1:23: +1:24
         StorageDead(_10);                // scope 2 at $DIR/inline_closure_captures.rs:+1:23: +1:24
         StorageDead(_9);                 // scope 1 at $DIR/inline_closure_captures.rs:+2:5: +2:9
diff --git a/tests/mir-opt/inline/inline_diverging.h.Inline.diff b/tests/mir-opt/inline/inline_diverging.h.Inline.diff
index f82fcf4c8..e1b2f7dbf 100644
--- a/tests/mir-opt/inline/inline_diverging.h.Inline.diff
+++ b/tests/mir-opt/inline/inline_diverging.h.Inline.diff
@@ -48,9 +48,7 @@
 +         StorageDead(_6);                 // scope 2 at $DIR/inline_diverging.rs:28:15: 28:16
 +         StorageLive(_8);                 // scope 3 at $DIR/inline_diverging.rs:29:6: 29:7
 +         _8 = move _3;                    // scope 3 at $DIR/inline_diverging.rs:29:6: 29:7
-+         Deinit(_1);                      // scope 3 at $DIR/inline_diverging.rs:29:5: 29:11
-+         (_1.0: !) = move _8;             // scope 3 at $DIR/inline_diverging.rs:29:5: 29:11
-+         (_1.1: !) = move _9;             // scope 3 at $DIR/inline_diverging.rs:29:5: 29:11
++         _1 = (move _8, move _9);         // scope 3 at $DIR/inline_diverging.rs:29:5: 29:11
 +         StorageDead(_8);                 // scope 3 at $DIR/inline_diverging.rs:29:10: 29:11
 +         StorageDead(_3);                 // scope 1 at $DIR/inline_diverging.rs:30:1: 30:2
 +         drop(_2) -> bb2;                 // scope 1 at $DIR/inline_diverging.rs:30:1: 30:2
diff --git a/tests/mir-opt/inline/inline_generator.main.Inline.diff b/tests/mir-opt/inline/inline_generator.main.Inline.diff
index f27b64c30..01f5052b6 100644
--- a/tests/mir-opt/inline/inline_generator.main.Inline.diff
+++ b/tests/mir-opt/inline/inline_generator.main.Inline.diff
@@ -7,7 +7,7 @@
       let mut _2: std::pin::Pin<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>; // in scope 0 at $DIR/inline_generator.rs:+1:14: +1:32
       let mut _3: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 0 at $DIR/inline_generator.rs:+1:23: +1:31
       let mut _4: [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 0 at $DIR/inline_generator.rs:+1:28: +1:31
-+     let mut _7: bool;                    // in scope 0 at $DIR/inline_generator.rs:+1:33: +1:46
++     let mut _5: bool;                    // in scope 0 at $DIR/inline_generator.rs:+1:33: +1:46
       scope 1 {
           debug _r => _1;                  // in scope 1 at $DIR/inline_generator.rs:+1:9: +1:11
       }
@@ -15,21 +15,19 @@
 +     }
 +     scope 3 (inlined Pin::<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>::new) { // at $DIR/inline_generator.rs:9:14: 9:32
 +         debug pointer => _3;             // in scope 3 at $SRC_DIR/core/src/pin.rs:LL:COL
-+         let mut _5: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 3 at $SRC_DIR/core/src/pin.rs:LL:COL
 +         scope 4 {
 +             scope 5 (inlined Pin::<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>::new_unchecked) { // at $SRC_DIR/core/src/pin.rs:LL:COL
-+                 debug pointer => _5;     // in scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
-+                 let mut _6: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
++                 debug pointer => _3;     // in scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
 +             }
 +         }
 +     }
 +     scope 6 (inlined g::{closure#0}) {   // at $DIR/inline_generator.rs:9:33: 9:46
-+         debug a => _7;                   // in scope 6 at $DIR/inline_generator.rs:15:6: 15:7
-+         let mut _8: i32;                 // in scope 6 at $DIR/inline_generator.rs:15:17: 15:39
-+         let mut _9: u32;                 // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         debug a => _5;                   // in scope 6 at $DIR/inline_generator.rs:15:6: 15:7
++         let mut _6: i32;                 // in scope 6 at $DIR/inline_generator.rs:15:17: 15:39
++         let mut _7: u32;                 // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         let mut _8: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         let mut _9: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
 +         let mut _10: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
-+         let mut _11: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
-+         let mut _12: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]; // in scope 6 at $DIR/inline_generator.rs:15:5: 15:41
 +     }
   
       bb0: {
@@ -44,8 +42,17 @@
 -     }
 - 
 -     bb1: {
-+         Deinit(_4);                      // scope 2 at $DIR/inline_generator.rs:15:5: 15:41
-+         discriminant(_4) = 0;            // scope 2 at $DIR/inline_generator.rs:15:5: 15:41
++         _4 = [generator@$DIR/inline_generator.rs:15:5: 15:8 (#0)]; // scope 2 at $DIR/inline_generator.rs:15:5: 15:41
++                                          // generator
++                                          // + def_id: DefId(0:7 ~ inline_generator[ea31]::g::{closure#0})
++                                          // + substs: [
++                                          //     bool,
++                                          //     i32,
++                                          //     bool,
++                                          //     {bool, i32},
++                                          //     (),
++                                          // ]
++                                          // + movability: Movable
           _3 = &mut _4;                    // scope 0 at $DIR/inline_generator.rs:+1:23: +1:31
 -         _2 = Pin::<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>::new(move _3) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/inline_generator.rs:+1:14: +1:32
 -                                          // mir::Constant
@@ -55,29 +62,22 @@
 -     }
 - 
 -     bb2: {
-+         StorageLive(_5);                 // scope 4 at $SRC_DIR/core/src/pin.rs:LL:COL
-+         _5 = move _3;                    // scope 4 at $SRC_DIR/core/src/pin.rs:LL:COL
-+         StorageLive(_6);                 // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
-+         _6 = move _5;                    // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
-+         Deinit(_2);                      // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
-+         (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]) = move _6; // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
-+         StorageDead(_6);                 // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
-+         StorageDead(_5);                 // scope 4 at $SRC_DIR/core/src/pin.rs:LL:COL
++         _2 = Pin::<&mut [generator@$DIR/inline_generator.rs:15:5: 15:8]> { pointer: move _3 }; // scope 5 at $SRC_DIR/core/src/pin.rs:LL:COL
           StorageDead(_3);                 // scope 0 at $DIR/inline_generator.rs:+1:31: +1:32
 -         _1 = <[generator@$DIR/inline_generator.rs:15:5: 15:8] as Generator<bool>>::resume(move _2, const false) -> [return: bb3, unwind: bb4]; // scope 0 at $DIR/inline_generator.rs:+1:14: +1:46
 -                                          // mir::Constant
 -                                          // + span: $DIR/inline_generator.rs:9:33: 9:39
 -                                          // + literal: Const { ty: for<'a> fn(Pin<&'a mut [generator@$DIR/inline_generator.rs:15:5: 15:8]>, bool) -> GeneratorState<<[generator@$DIR/inline_generator.rs:15:5: 15:8] as Generator<bool>>::Yield, <[generator@$DIR/inline_generator.rs:15:5: 15:8] as Generator<bool>>::Return> {<[generator@$DIR/inline_generator.rs:15:5: 15:8] as Generator<bool>>::resume}, val: Value(<ZST>) }
-+         StorageLive(_7);                 // scope 0 at $DIR/inline_generator.rs:+1:33: +1:46
-+         _7 = const false;                // scope 0 at $DIR/inline_generator.rs:+1:33: +1:46
-+         _10 = deref_copy (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
-+         _9 = discriminant((*_10));       // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
-+         switchInt(move _9) -> [0: bb3, 1: bb8, 3: bb7, otherwise: bb9]; // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         StorageLive(_5);                 // scope 0 at $DIR/inline_generator.rs:+1:33: +1:46
++         _5 = const false;                // scope 0 at $DIR/inline_generator.rs:+1:33: +1:46
++         _8 = deref_copy (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         _7 = discriminant((*_8));        // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         switchInt(move _7) -> [0: bb3, 1: bb8, 3: bb7, otherwise: bb9]; // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
       }
   
 -     bb3: {
 +     bb1: {
-+         StorageDead(_7);                 // scope 0 at $DIR/inline_generator.rs:+1:33: +1:46
++         StorageDead(_5);                 // scope 0 at $DIR/inline_generator.rs:+1:33: +1:46
           StorageDead(_2);                 // scope 0 at $DIR/inline_generator.rs:+1:45: +1:46
           StorageDead(_4);                 // scope 0 at $DIR/inline_generator.rs:+1:46: +1:47
           _0 = const ();                   // scope 0 at $DIR/inline_generator.rs:+0:11: +2:2
@@ -91,37 +91,33 @@
 +     }
 + 
 +     bb3: {
-+         StorageLive(_8);                 // scope 6 at $DIR/inline_generator.rs:15:17: 15:39
-+         switchInt(move _7) -> [0: bb5, otherwise: bb4]; // scope 6 at $DIR/inline_generator.rs:15:20: 15:21
++         StorageLive(_6);                 // scope 6 at $DIR/inline_generator.rs:15:17: 15:39
++         switchInt(_5) -> [0: bb5, otherwise: bb4]; // scope 6 at $DIR/inline_generator.rs:15:20: 15:21
 +     }
 + 
 +     bb4: {
-+         _8 = const 7_i32;                // scope 6 at $DIR/inline_generator.rs:15:24: 15:25
++         _6 = const 7_i32;                // scope 6 at $DIR/inline_generator.rs:15:24: 15:25
 +         goto -> bb6;                     // scope 6 at $DIR/inline_generator.rs:15:17: 15:39
 +     }
 + 
 +     bb5: {
-+         _8 = const 13_i32;               // scope 6 at $DIR/inline_generator.rs:15:35: 15:37
++         _6 = const 13_i32;               // scope 6 at $DIR/inline_generator.rs:15:35: 15:37
 +         goto -> bb6;                     // scope 6 at $DIR/inline_generator.rs:15:17: 15:39
 +     }
 + 
 +     bb6: {
-+         Deinit(_1);                      // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
-+         ((_1 as Yielded).0: i32) = move _8; // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
-+         discriminant(_1) = 0;            // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
-+         _11 = deref_copy (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
-+         discriminant((*_11)) = 3;        // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
++         _1 = GeneratorState::<i32, bool>::Yielded(move _6); // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
++         _9 = deref_copy (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
++         discriminant((*_9)) = 3;         // scope 6 at $DIR/inline_generator.rs:15:11: 15:39
 +         goto -> bb1;                     // scope 0 at $DIR/inline_generator.rs:15:11: 15:39
 +     }
 + 
 +     bb7: {
-+         StorageLive(_8);                 // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
-+         StorageDead(_8);                 // scope 6 at $DIR/inline_generator.rs:15:38: 15:39
-+         Deinit(_1);                      // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
-+         ((_1 as Complete).0: bool) = move _7; // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
-+         discriminant(_1) = 1;            // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
-+         _12 = deref_copy (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
-+         discriminant((*_12)) = 1;        // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
++         StorageLive(_6);                 // scope 6 at $DIR/inline_generator.rs:15:5: 15:41
++         StorageDead(_6);                 // scope 6 at $DIR/inline_generator.rs:15:38: 15:39
++         _1 = GeneratorState::<i32, bool>::Complete(_5); // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
++         _10 = deref_copy (_2.0: &mut [generator@$DIR/inline_generator.rs:15:5: 15:8]); // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
++         discriminant((*_10)) = 1;        // scope 6 at $DIR/inline_generator.rs:15:41: 15:41
 +         goto -> bb1;                     // scope 0 at $DIR/inline_generator.rs:15:41: 15:41
 +     }
 + 
diff --git a/tests/mir-opt/inline/inline_into_box_place.main.Inline.diff b/tests/mir-opt/inline/inline_into_box_place.main.Inline.diff
index a28da146e..a1cbf0d3e 100644
--- a/tests/mir-opt/inline/inline_into_box_place.main.Inline.diff
+++ b/tests/mir-opt/inline/inline_into_box_place.main.Inline.diff
@@ -51,9 +51,7 @@
 +                                          // + span: $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
 +                                          // + user_ty: UserType(0)
 +                                          // + literal: Const { ty: alloc::raw_vec::RawVec<u32>, val: Unevaluated(alloc::raw_vec::RawVec::<T>::NEW, [u32], None) }
-+         Deinit(_9);                      // scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
-+         (_9.0: alloc::raw_vec::RawVec<u32>) = move _10; // scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
-+         (_9.1: usize) = const 0_usize;   // scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
++         _9 = Vec::<u32> { buf: move _10, len: const 0_usize }; // scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
 +         StorageDead(_10);                // scope 3 at $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
 +         (*_8) = move _9;                 // scope 0 at $DIR/inline_into_box_place.rs:+1:33: +1:43
 +         StorageDead(_9);                 // scope 0 at $DIR/inline_into_box_place.rs:+1:33: +1:43
diff --git a/tests/mir-opt/inline/inline_trait_method_2.test2.Inline.after.mir b/tests/mir-opt/inline/inline_trait_method_2.test2.Inline.after.mir
index 73aea719e..b7c5bbecb 100644
--- a/tests/mir-opt/inline/inline_trait_method_2.test2.Inline.after.mir
+++ b/tests/mir-opt/inline/inline_trait_method_2.test2.Inline.after.mir
@@ -15,7 +15,7 @@ fn test2(_1: &dyn X) -> bool {
         _3 = &(*_1);                     // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
         _2 = move _3 as &dyn X (Pointer(Unsize)); // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
         StorageDead(_3);                 // scope 0 at $DIR/inline_trait_method_2.rs:+1:10: +1:11
-        _0 = <dyn X as X>::y(move _2) -> bb1; // scope 1 at $DIR/inline_trait_method_2.rs:10:5: 10:10
+        _0 = <dyn X as X>::y(_2) -> bb1; // scope 1 at $DIR/inline_trait_method_2.rs:10:5: 10:10
                                          // mir::Constant
                                          // + span: $DIR/inline_trait_method_2.rs:10:7: 10:8
                                          // + literal: Const { ty: for<'a> fn(&'a dyn X) -> bool {<dyn X as X>::y}, val: Value(<ZST>) }
diff --git a/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.a.Inline.after.mir b/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.a.Inline.after.mir
index dc0c32350..6441a9668 100644
--- a/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.a.Inline.after.mir
+++ b/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.a.Inline.after.mir
@@ -8,7 +8,6 @@ fn a(_1: &mut [T]) -> &mut [T] {
     let mut _4: &mut [T];                // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
     scope 1 (inlined <[T] as AsMut<[T]>>::as_mut) { // at $DIR/issue_58867_inline_as_ref_as_mut.rs:3:7: 3:15
         debug self => _4;                // in scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-        let mut _5: &mut [T];            // in scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
     }
 
     bb0: {
@@ -16,10 +15,7 @@ fn a(_1: &mut [T]) -> &mut [T] {
         StorageLive(_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
         StorageLive(_4);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
         _4 = &mut (*_1);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
-        StorageLive(_5);                 // scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-        _5 = &mut (*_4);                 // scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-        _3 = &mut (*_5);                 // scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-        StorageDead(_5);                 // scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
+        _3 = _4;                         // scope 1 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
         _2 = &mut (*_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
         StorageDead(_4);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:14: +1:15
         _0 = &mut (*_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
diff --git a/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir b/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir
index b6aff3014..21570a88a 100644
--- a/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir
+++ b/tests/mir-opt/inline/issue_58867_inline_as_ref_as_mut.b.Inline.after.mir
@@ -8,10 +8,8 @@ fn b(_1: &mut Box<T>) -> &mut T {
     let mut _4: &mut std::boxed::Box<T>; // in scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
     scope 1 (inlined <Box<T> as AsMut<T>>::as_mut) { // at $DIR/issue_58867_inline_as_ref_as_mut.rs:8:7: 8:15
         debug self => _4;                // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        let mut _5: &mut T;              // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        let mut _6: &mut T;              // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        let mut _7: std::boxed::Box<T>;  // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        let mut _8: *const T;            // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
+        let mut _5: std::boxed::Box<T>;  // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
+        let mut _6: *const T;            // in scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
     }
 
     bb0: {
@@ -19,15 +17,9 @@ fn b(_1: &mut Box<T>) -> &mut T {
         StorageLive(_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
         StorageLive(_4);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
         _4 = &mut (*_1);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
-        StorageLive(_5);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        StorageLive(_6);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        _7 = deref_copy (*_4);           // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        _8 = (((_7.0: std::ptr::Unique<T>).0: std::ptr::NonNull<T>).0: *const T); // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        _6 = &mut (*_8);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        _5 = &mut (*_6);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        _3 = &mut (*_5);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        StorageDead(_6);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
-        StorageDead(_5);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
+        _5 = deref_copy (*_4);           // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
+        _6 = (((_5.0: std::ptr::Unique<T>).0: std::ptr::NonNull<T>).0: *const T); // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
+        _3 = &mut (*_6);                 // scope 1 at $SRC_DIR/alloc/src/boxed.rs:LL:COL
         _2 = &mut (*_3);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
         StorageDead(_4);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:14: +1:15
         _0 = &mut (*_2);                 // scope 0 at $DIR/issue_58867_inline_as_ref_as_mut.rs:+1:5: +1:15
diff --git a/tests/mir-opt/inline/issue_76997_inline_scopes_parenting.main.Inline.after.mir b/tests/mir-opt/inline/issue_76997_inline_scopes_parenting.main.Inline.after.mir
index d99ae1a6c..4dd1aad48 100644
--- a/tests/mir-opt/inline/issue_76997_inline_scopes_parenting.main.Inline.after.mir
+++ b/tests/mir-opt/inline/issue_76997_inline_scopes_parenting.main.Inline.after.mir
@@ -20,14 +20,20 @@ fn main() -> () {
 
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:9: +1:10
-        Deinit(_1);                      // scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:13: +1:33
+        _1 = [closure@$DIR/issue_76997_inline_scopes_parenting.rs:5:13: 5:16]; // scope 0 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:13: +1:33
+                                         // closure
+                                         // + def_id: DefId(0:4 ~ issue_76997_inline_scopes_parenting[bc59]::main::{closure#0})
+                                         // + substs: [
+                                         //     i8,
+                                         //     extern "rust-call" fn(((),)),
+                                         //     (),
+                                         // ]
         StorageLive(_2);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:6
         _2 = &_1;                        // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:6
         StorageLive(_3);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
         StorageLive(_4);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:7: +2:9
-        Deinit(_4);                      // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:7: +2:9
-        Deinit(_3);                      // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
-        (_3.0: ()) = move _4;            // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
+        _4 = ();                         // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:7: +2:9
+        _3 = (move _4,);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
         StorageLive(_5);                 // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
         _5 = move (_3.0: ());            // scope 1 at $DIR/issue_76997_inline_scopes_parenting.rs:+2:5: +2:10
         StorageLive(_6);                 // scope 2 at $DIR/issue_76997_inline_scopes_parenting.rs:+1:23: +1:24
diff --git a/tests/mir-opt/inline/issue_78442.bar.Inline.diff b/tests/mir-opt/inline/issue_78442.bar.Inline.diff
index 51a98465f..aa62e4a16 100644
--- a/tests/mir-opt/inline/issue_78442.bar.Inline.diff
+++ b/tests/mir-opt/inline/issue_78442.bar.Inline.diff
@@ -25,7 +25,7 @@
       bb1: {
           _3 = &_4;                        // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
           StorageLive(_5);                 // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
-          Deinit(_5);                      // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
+          _5 = ();                         // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
 -         _2 = <fn() {foo} as Fn<()>>::call(move _3, move _5) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
 -                                          // mir::Constant
 -                                          // + span: $DIR/issue_78442.rs:11:5: 11:15
diff --git a/tests/mir-opt/inline/issue_78442.bar.RevealAll.diff b/tests/mir-opt/inline/issue_78442.bar.RevealAll.diff
index e47466c5e..21055c6bf 100644
--- a/tests/mir-opt/inline/issue_78442.bar.RevealAll.diff
+++ b/tests/mir-opt/inline/issue_78442.bar.RevealAll.diff
@@ -24,7 +24,7 @@
       bb1: {
           _3 = &_4;                        // scope 0 at $DIR/issue_78442.rs:+4:5: +4:15
           StorageLive(_5);                 // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
-          Deinit(_5);                      // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
+          _5 = ();                         // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
 -         _2 = <impl Fn() as Fn<()>>::call(move _3, move _5) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
 +         _2 = <fn() {foo} as Fn<()>>::call(move _3, move _5) -> [return: bb2, unwind: bb4]; // scope 0 at $DIR/issue_78442.rs:+4:5: +4:17
                                            // mir::Constant
diff --git a/tests/mir-opt/intrinsic_asserts.generic.InstCombine.diff b/tests/mir-opt/intrinsic_asserts.generic.InstCombine.diff
new file mode 100644
index 000000000..8ff64c1ea
--- /dev/null
+++ b/tests/mir-opt/intrinsic_asserts.generic.InstCombine.diff
@@ -0,0 +1,42 @@
+- // MIR for `generic` before InstCombine
++ // MIR for `generic` after InstCombine
+  
+  fn generic() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/intrinsic_asserts.rs:+0:21: +0:21
+      let _1: ();                          // in scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:46
+      let _2: ();                          // in scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:47
+      let _3: ();                          // in scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:60
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:46
+          _1 = assert_inhabited::<T>() -> bb1; // scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:46
+                                           // mir::Constant
+                                           // + span: $DIR/intrinsic_asserts.rs:25:5: 25:44
+                                           // + literal: Const { ty: extern "rust-intrinsic" fn() {assert_inhabited::<T>}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_1);                 // scope 0 at $DIR/intrinsic_asserts.rs:+1:46: +1:47
+          StorageLive(_2);                 // scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:47
+          _2 = assert_zero_valid::<T>() -> bb2; // scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:47
+                                           // mir::Constant
+                                           // + span: $DIR/intrinsic_asserts.rs:26:5: 26:45
+                                           // + literal: Const { ty: extern "rust-intrinsic" fn() {assert_zero_valid::<T>}, val: Value(<ZST>) }
+      }
+  
+      bb2: {
+          StorageDead(_2);                 // scope 0 at $DIR/intrinsic_asserts.rs:+2:47: +2:48
+          StorageLive(_3);                 // scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:60
+          _3 = assert_mem_uninitialized_valid::<T>() -> bb3; // scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:60
+                                           // mir::Constant
+                                           // + span: $DIR/intrinsic_asserts.rs:27:5: 27:58
+                                           // + literal: Const { ty: extern "rust-intrinsic" fn() {assert_mem_uninitialized_valid::<T>}, val: Value(<ZST>) }
+      }
+  
+      bb3: {
+          StorageDead(_3);                 // scope 0 at $DIR/intrinsic_asserts.rs:+3:60: +3:61
+          nop;                             // scope 0 at $DIR/intrinsic_asserts.rs:+0:21: +4:2
+          return;                          // scope 0 at $DIR/intrinsic_asserts.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/intrinsic_asserts.panics.InstCombine.diff b/tests/mir-opt/intrinsic_asserts.panics.InstCombine.diff
new file mode 100644
index 000000000..ddc015903
--- /dev/null
+++ b/tests/mir-opt/intrinsic_asserts.panics.InstCombine.diff
@@ -0,0 +1,47 @@
+- // MIR for `panics` before InstCombine
++ // MIR for `panics` after InstCombine
+  
+  fn panics() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/intrinsic_asserts.rs:+0:17: +0:17
+      let _1: ();                          // in scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:50
+      let _2: ();                          // in scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:49
+      let _3: ();                          // in scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:62
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:50
+-         _1 = assert_inhabited::<Never>() -> bb1; // scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:50
++         _1 = assert_inhabited::<Never>(); // scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:50
+                                           // mir::Constant
+                                           // + span: $DIR/intrinsic_asserts.rs:17:5: 17:48
+                                           // + literal: Const { ty: extern "rust-intrinsic" fn() {assert_inhabited::<Never>}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_1);                 // scope 0 at $DIR/intrinsic_asserts.rs:+1:50: +1:51
+          StorageLive(_2);                 // scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:49
+-         _2 = assert_zero_valid::<&u8>() -> bb2; // scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:49
++         _2 = assert_zero_valid::<&u8>(); // scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:49
+                                           // mir::Constant
+                                           // + span: $DIR/intrinsic_asserts.rs:18:5: 18:47
+                                           // + user_ty: UserType(0)
+                                           // + literal: Const { ty: extern "rust-intrinsic" fn() {assert_zero_valid::<&u8>}, val: Value(<ZST>) }
+      }
+  
+      bb2: {
+          StorageDead(_2);                 // scope 0 at $DIR/intrinsic_asserts.rs:+2:49: +2:50
+          StorageLive(_3);                 // scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:62
+-         _3 = assert_mem_uninitialized_valid::<&u8>() -> bb3; // scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:62
++         _3 = assert_mem_uninitialized_valid::<&u8>(); // scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:62
+                                           // mir::Constant
+                                           // + span: $DIR/intrinsic_asserts.rs:19:5: 19:60
+                                           // + user_ty: UserType(1)
+                                           // + literal: Const { ty: extern "rust-intrinsic" fn() {assert_mem_uninitialized_valid::<&u8>}, val: Value(<ZST>) }
+      }
+  
+      bb3: {
+          StorageDead(_3);                 // scope 0 at $DIR/intrinsic_asserts.rs:+3:62: +3:63
+          nop;                             // scope 0 at $DIR/intrinsic_asserts.rs:+0:17: +4:2
+          return;                          // scope 0 at $DIR/intrinsic_asserts.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/intrinsic_asserts.removable.InstCombine.diff b/tests/mir-opt/intrinsic_asserts.removable.InstCombine.diff
new file mode 100644
index 000000000..568fbf1a0
--- /dev/null
+++ b/tests/mir-opt/intrinsic_asserts.removable.InstCombine.diff
@@ -0,0 +1,45 @@
+- // MIR for `removable` before InstCombine
++ // MIR for `removable` after InstCombine
+  
+  fn removable() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/intrinsic_asserts.rs:+0:20: +0:20
+      let _1: ();                          // in scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:47
+      let _2: ();                          // in scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:48
+      let _3: ();                          // in scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:61
+  
+      bb0: {
+          StorageLive(_1);                 // scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:47
+-         _1 = assert_inhabited::<()>() -> bb1; // scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:47
+-                                          // mir::Constant
+-                                          // + span: $DIR/intrinsic_asserts.rs:7:5: 7:45
+-                                          // + literal: Const { ty: extern "rust-intrinsic" fn() {assert_inhabited::<()>}, val: Value(<ZST>) }
++         goto -> bb1;                     // scope 0 at $DIR/intrinsic_asserts.rs:+1:5: +1:47
+      }
+  
+      bb1: {
+          StorageDead(_1);                 // scope 0 at $DIR/intrinsic_asserts.rs:+1:47: +1:48
+          StorageLive(_2);                 // scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:48
+-         _2 = assert_zero_valid::<u8>() -> bb2; // scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:48
+-                                          // mir::Constant
+-                                          // + span: $DIR/intrinsic_asserts.rs:8:5: 8:46
+-                                          // + literal: Const { ty: extern "rust-intrinsic" fn() {assert_zero_valid::<u8>}, val: Value(<ZST>) }
++         goto -> bb2;                     // scope 0 at $DIR/intrinsic_asserts.rs:+2:5: +2:48
+      }
+  
+      bb2: {
+          StorageDead(_2);                 // scope 0 at $DIR/intrinsic_asserts.rs:+2:48: +2:49
+          StorageLive(_3);                 // scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:61
+-         _3 = assert_mem_uninitialized_valid::<u8>() -> bb3; // scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:61
+-                                          // mir::Constant
+-                                          // + span: $DIR/intrinsic_asserts.rs:9:5: 9:59
+-                                          // + literal: Const { ty: extern "rust-intrinsic" fn() {assert_mem_uninitialized_valid::<u8>}, val: Value(<ZST>) }
++         goto -> bb3;                     // scope 0 at $DIR/intrinsic_asserts.rs:+3:5: +3:61
+      }
+  
+      bb3: {
+          StorageDead(_3);                 // scope 0 at $DIR/intrinsic_asserts.rs:+3:61: +3:62
+          nop;                             // scope 0 at $DIR/intrinsic_asserts.rs:+0:20: +4:2
+          return;                          // scope 0 at $DIR/intrinsic_asserts.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/intrinsic_asserts.rs b/tests/mir-opt/intrinsic_asserts.rs
new file mode 100644
index 000000000..8fb99cdf6
--- /dev/null
+++ b/tests/mir-opt/intrinsic_asserts.rs
@@ -0,0 +1,28 @@
+#![crate_type = "lib"]
+#![feature(core_intrinsics)]
+
+// All these assertions pass, so all the intrinsic calls should be deleted.
+// EMIT_MIR intrinsic_asserts.removable.InstCombine.diff
+pub fn removable() {
+    core::intrinsics::assert_inhabited::<()>();
+    core::intrinsics::assert_zero_valid::<u8>();
+    core::intrinsics::assert_mem_uninitialized_valid::<u8>();
+}
+
+enum Never {}
+
+// These assertions all diverge, so their target blocks should become None.
+// EMIT_MIR intrinsic_asserts.panics.InstCombine.diff
+pub fn panics() {
+    core::intrinsics::assert_inhabited::<Never>();
+    core::intrinsics::assert_zero_valid::<&u8>();
+    core::intrinsics::assert_mem_uninitialized_valid::<&u8>();
+}
+
+// Whether or not these asserts pass isn't known, so they shouldn't be modified.
+// EMIT_MIR intrinsic_asserts.generic.InstCombine.diff
+pub fn generic<T>() {
+    core::intrinsics::assert_inhabited::<T>();
+    core::intrinsics::assert_zero_valid::<T>();
+    core::intrinsics::assert_mem_uninitialized_valid::<T>();
+}
diff --git a/tests/mir-opt/issue_101973.inner.ConstProp.diff b/tests/mir-opt/issue_101973.inner.ConstProp.diff
index b2706e5a4..6db8e4d26 100644
--- a/tests/mir-opt/issue_101973.inner.ConstProp.diff
+++ b/tests/mir-opt/issue_101973.inner.ConstProp.diff
@@ -15,7 +15,7 @@
       let mut _10: (u32, bool);            // in scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
       let mut _11: (u32, bool);            // in scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
       scope 1 (inlined imm8) {             // at $DIR/issue_101973.rs:14:5: 14:17
-          debug x => _5;                   // in scope 1 at $DIR/issue_101973.rs:5:13: 5:14
+          debug x => _1;                   // in scope 1 at $DIR/issue_101973.rs:5:13: 5:14
           let mut _12: u32;                // in scope 1 at $DIR/issue_101973.rs:7:12: 7:27
           let mut _13: u32;                // in scope 1 at $DIR/issue_101973.rs:7:12: 7:20
           let mut _14: (u32, bool);        // in scope 1 at $DIR/issue_101973.rs:7:12: 7:20
@@ -26,25 +26,20 @@
       scope 3 (inlined core::num::<impl u32>::rotate_right) { // at $DIR/issue_101973.rs:14:18: 14:58
           debug self => _4;                // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
           debug n => _6;                   // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          let mut _15: u32;                // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          let mut _16: u32;                // in scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
       }
   
       bb0: {
           StorageLive(_2);                 // scope 0 at $DIR/issue_101973.rs:+1:5: +1:65
           StorageLive(_3);                 // scope 0 at $DIR/issue_101973.rs:+1:5: +1:58
           StorageLive(_4);                 // scope 0 at $DIR/issue_101973.rs:+1:5: +1:17
-          StorageLive(_5);                 // scope 0 at $DIR/issue_101973.rs:+1:10: +1:16
-          _5 = _1;                         // scope 0 at $DIR/issue_101973.rs:+1:10: +1:16
           StorageLive(_12);                // scope 2 at $DIR/issue_101973.rs:7:12: 7:27
           StorageLive(_13);                // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
-          _14 = CheckedShr(_5, const 0_i32); // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
+          _14 = CheckedShr(_1, const 0_i32); // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
           assert(!move (_14.1: bool), "attempt to shift right by `{}`, which would overflow", const 0_i32) -> bb3; // scope 2 at $DIR/issue_101973.rs:7:12: 7:20
       }
   
       bb1: {
           _8 = move (_10.0: u32);          // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
-          StorageDead(_9);                 // scope 0 at $DIR/issue_101973.rs:+1:44: +1:45
           _7 = BitAnd(move _8, const 15_u32); // scope 0 at $DIR/issue_101973.rs:+1:31: +1:52
           StorageDead(_8);                 // scope 0 at $DIR/issue_101973.rs:+1:51: +1:52
           _11 = CheckedShl(_7, const 1_i32); // scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
@@ -54,11 +49,7 @@
       bb2: {
           _6 = move (_11.0: u32);          // scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
           StorageDead(_7);                 // scope 0 at $DIR/issue_101973.rs:+1:56: +1:57
-          StorageLive(_15);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          _15 = _4;                        // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          StorageLive(_16);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          _16 = _6;                        // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          _3 = rotate_right::<u32>(move _15, move _16) -> bb4; // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
+          _3 = rotate_right::<u32>(_4, _6) -> bb4; // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
                                            // mir::Constant
                                            // + span: $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
                                            // + literal: Const { ty: extern "rust-intrinsic" fn(u32, u32) -> u32 {rotate_right::<u32>}, val: Value(<ZST>) }
@@ -70,19 +61,14 @@
           StorageDead(_13);                // scope 2 at $DIR/issue_101973.rs:7:26: 7:27
           _4 = BitOr(const 0_u32, move _12); // scope 2 at $DIR/issue_101973.rs:7:5: 7:27
           StorageDead(_12);                // scope 2 at $DIR/issue_101973.rs:7:26: 7:27
-          StorageDead(_5);                 // scope 0 at $DIR/issue_101973.rs:+1:16: +1:17
           StorageLive(_6);                 // scope 0 at $DIR/issue_101973.rs:+1:31: +1:57
           StorageLive(_7);                 // scope 0 at $DIR/issue_101973.rs:+1:31: +1:52
           StorageLive(_8);                 // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
-          StorageLive(_9);                 // scope 0 at $DIR/issue_101973.rs:+1:33: +1:39
-          _9 = _1;                         // scope 0 at $DIR/issue_101973.rs:+1:33: +1:39
-          _10 = CheckedShr(_9, const 8_i32); // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
+          _10 = CheckedShr(_1, const 8_i32); // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
           assert(!move (_10.1: bool), "attempt to shift right by `{}`, which would overflow", const 8_i32) -> bb1; // scope 0 at $DIR/issue_101973.rs:+1:32: +1:45
       }
   
       bb4: {
-          StorageDead(_16);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
-          StorageDead(_15);                // scope 3 at $SRC_DIR/core/src/num/uint_macros.rs:LL:COL
           StorageDead(_6);                 // scope 0 at $DIR/issue_101973.rs:+1:57: +1:58
           StorageDead(_4);                 // scope 0 at $DIR/issue_101973.rs:+1:57: +1:58
           _2 = move _3 as i32 (IntToInt);  // scope 0 at $DIR/issue_101973.rs:+1:5: +1:65
diff --git a/tests/mir-opt/issue_41110.main.ElaborateDrops.after.mir b/tests/mir-opt/issue_41110.main.ElaborateDrops.after.mir
deleted file mode 100644
index c2ea3ac50..000000000
--- a/tests/mir-opt/issue_41110.main.ElaborateDrops.after.mir
+++ /dev/null
@@ -1,70 +0,0 @@
-// MIR for `main` after ElaborateDrops
-
-fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue_41110.rs:+0:11: +0:11
-    let _1: ();                          // in scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
-    let mut _2: S;                       // in scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
-    let mut _3: S;                       // in scope 0 at $DIR/issue_41110.rs:+1:21: +1:27
-    let mut _4: S;                       // in scope 0 at $DIR/issue_41110.rs:+1:21: +1:22
-    let mut _5: bool;                    // in scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
-    scope 1 {
-        debug x => _1;                   // in scope 1 at $DIR/issue_41110.rs:+1:9: +1:10
-    }
-
-    bb0: {
-        _5 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
-        StorageLive(_1);                 // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
-        StorageLive(_2);                 // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
-        _5 = const true;                 // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
-        _2 = S;                          // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
-        StorageLive(_3);                 // scope 0 at $DIR/issue_41110.rs:+1:21: +1:27
-        StorageLive(_4);                 // scope 0 at $DIR/issue_41110.rs:+1:21: +1:22
-        _4 = S;                          // scope 0 at $DIR/issue_41110.rs:+1:21: +1:22
-        _3 = S::id(move _4) -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue_41110.rs:+1:21: +1:27
-                                         // mir::Constant
-                                         // + span: $DIR/issue_41110.rs:8:23: 8:25
-                                         // + literal: Const { ty: fn(S) -> S {S::id}, val: Value(<ZST>) }
-    }
-
-    bb1: {
-        StorageDead(_4);                 // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27
-        _5 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:13: +1:28
-        _1 = S::other(move _2, move _3) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:28
-                                         // mir::Constant
-                                         // + span: $DIR/issue_41110.rs:8:15: 8:20
-                                         // + literal: Const { ty: fn(S, S) {S::other}, val: Value(<ZST>) }
-    }
-
-    bb2: {
-        StorageDead(_3);                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
-        _5 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
-        StorageDead(_2);                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
-        _0 = const ();                   // scope 0 at $DIR/issue_41110.rs:+0:11: +2:2
-        StorageDead(_1);                 // scope 0 at $DIR/issue_41110.rs:+2:1: +2:2
-        return;                          // scope 0 at $DIR/issue_41110.rs:+2:2: +2:2
-    }
-
-    bb3 (cleanup): {
-        goto -> bb5;                     // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
-    }
-
-    bb4 (cleanup): {
-        goto -> bb5;                     // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27
-    }
-
-    bb5 (cleanup): {
-        goto -> bb8;                     // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
-    }
-
-    bb6 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue_41110.rs:+0:1: +2:2
-    }
-
-    bb7 (cleanup): {
-        drop(_2) -> bb6;                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
-    }
-
-    bb8 (cleanup): {
-        switchInt(_5) -> [0: bb6, otherwise: bb7]; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
-    }
-}
diff --git a/tests/mir-opt/issue_41110.main.ElaborateDrops.diff b/tests/mir-opt/issue_41110.main.ElaborateDrops.diff
new file mode 100644
index 000000000..7ac75b51a
--- /dev/null
+++ b/tests/mir-opt/issue_41110.main.ElaborateDrops.diff
@@ -0,0 +1,75 @@
+- // MIR for `main` before ElaborateDrops
++ // MIR for `main` after ElaborateDrops
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/issue_41110.rs:+0:11: +0:11
+      let _1: ();                          // in scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+      let mut _2: S;                       // in scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+      let mut _3: S;                       // in scope 0 at $DIR/issue_41110.rs:+1:21: +1:27
+      let mut _4: S;                       // in scope 0 at $DIR/issue_41110.rs:+1:21: +1:22
++     let mut _5: bool;                    // in scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
+      scope 1 {
+          debug x => _1;                   // in scope 1 at $DIR/issue_41110.rs:+1:9: +1:10
+      }
+  
+      bb0: {
++         _5 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+          StorageLive(_1);                 // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+          StorageLive(_2);                 // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
++         _5 = const true;                 // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+          _2 = S;                          // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+          StorageLive(_3);                 // scope 0 at $DIR/issue_41110.rs:+1:21: +1:27
+          StorageLive(_4);                 // scope 0 at $DIR/issue_41110.rs:+1:21: +1:22
+          _4 = S;                          // scope 0 at $DIR/issue_41110.rs:+1:21: +1:22
+          _3 = S::id(move _4) -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue_41110.rs:+1:21: +1:27
+                                           // mir::Constant
+                                           // + span: $DIR/issue_41110.rs:8:23: 8:25
+                                           // + literal: Const { ty: fn(S) -> S {S::id}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_4);                 // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27
++         _5 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:13: +1:28
+          _1 = S::other(move _2, move _3) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:28
+                                           // mir::Constant
+                                           // + span: $DIR/issue_41110.rs:8:15: 8:20
+                                           // + literal: Const { ty: fn(S, S) {S::other}, val: Value(<ZST>) }
+      }
+  
+      bb2: {
+          StorageDead(_3);                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
++         _5 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
+          StorageDead(_2);                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
+          _0 = const ();                   // scope 0 at $DIR/issue_41110.rs:+0:11: +2:2
+          StorageDead(_1);                 // scope 0 at $DIR/issue_41110.rs:+2:1: +2:2
+          return;                          // scope 0 at $DIR/issue_41110.rs:+2:2: +2:2
+      }
+  
+      bb3 (cleanup): {
+-         drop(_3) -> bb5;                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
++         goto -> bb5;                     // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
+      }
+  
+      bb4 (cleanup): {
+-         drop(_4) -> bb5;                 // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27
++         goto -> bb5;                     // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27
+      }
+  
+      bb5 (cleanup): {
+-         drop(_2) -> bb6;                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
++         goto -> bb8;                     // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
+      }
+  
+      bb6 (cleanup): {
+          resume;                          // scope 0 at $DIR/issue_41110.rs:+0:1: +2:2
++     }
++ 
++     bb7 (cleanup): {
++         drop(_2) -> bb6;                 // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
++     }
++ 
++     bb8 (cleanup): {
++         switchInt(_5) -> [0: bb6, otherwise: bb7]; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28
+      }
+  }
+  
diff --git a/tests/mir-opt/issue_41110.rs b/tests/mir-opt/issue_41110.rs
index 638dc601e..e1067ce53 100644
--- a/tests/mir-opt/issue_41110.rs
+++ b/tests/mir-opt/issue_41110.rs
@@ -3,14 +3,14 @@
 // check that we don't emit multiple drop flags when they are not needed.
 
 
-// EMIT_MIR issue_41110.main.ElaborateDrops.after.mir
+// EMIT_MIR issue_41110.main.ElaborateDrops.diff
 fn main() {
     let x = S.other(S.id());
 }
 
 // no_mangle to make sure this gets instantiated even in an executable.
 #[no_mangle]
-// EMIT_MIR issue_41110.test.ElaborateDrops.after.mir
+// EMIT_MIR issue_41110.test.ElaborateDrops.diff
 pub fn test() {
     let u = S;
     let mut v = S;
diff --git a/tests/mir-opt/issue_41110.test.ElaborateDrops.after.mir b/tests/mir-opt/issue_41110.test.ElaborateDrops.after.mir
deleted file mode 100644
index 82989c3f0..000000000
--- a/tests/mir-opt/issue_41110.test.ElaborateDrops.after.mir
+++ /dev/null
@@ -1,101 +0,0 @@
-// MIR for `test` after ElaborateDrops
-
-fn test() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue_41110.rs:+0:15: +0:15
-    let _1: S;                           // in scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
-    let _3: ();                          // in scope 0 at $DIR/issue_41110.rs:+3:5: +3:12
-    let mut _4: S;                       // in scope 0 at $DIR/issue_41110.rs:+3:10: +3:11
-    let mut _5: S;                       // in scope 0 at $DIR/issue_41110.rs:+4:9: +4:10
-    let mut _6: bool;                    // in scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
-    scope 1 {
-        debug u => _1;                   // in scope 1 at $DIR/issue_41110.rs:+1:9: +1:10
-        let mut _2: S;                   // in scope 1 at $DIR/issue_41110.rs:+2:9: +2:14
-        scope 2 {
-            debug v => _2;               // in scope 2 at $DIR/issue_41110.rs:+2:9: +2:14
-        }
-    }
-
-    bb0: {
-        _6 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
-        StorageLive(_1);                 // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
-        _6 = const true;                 // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
-        _1 = S;                          // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
-        StorageLive(_2);                 // scope 1 at $DIR/issue_41110.rs:+2:9: +2:14
-        _2 = S;                          // scope 1 at $DIR/issue_41110.rs:+2:17: +2:18
-        StorageLive(_3);                 // scope 2 at $DIR/issue_41110.rs:+3:5: +3:12
-        StorageLive(_4);                 // scope 2 at $DIR/issue_41110.rs:+3:10: +3:11
-        _4 = move _2;                    // scope 2 at $DIR/issue_41110.rs:+3:10: +3:11
-        _3 = std::mem::drop::<S>(move _4) -> [return: bb1, unwind: bb7]; // scope 2 at $DIR/issue_41110.rs:+3:5: +3:12
-                                         // mir::Constant
-                                         // + span: $DIR/issue_41110.rs:17:5: 17:9
-                                         // + literal: Const { ty: fn(S) {std::mem::drop::<S>}, val: Value(<ZST>) }
-    }
-
-    bb1: {
-        StorageDead(_4);                 // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12
-        StorageDead(_3);                 // scope 2 at $DIR/issue_41110.rs:+3:12: +3:13
-        StorageLive(_5);                 // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
-        _6 = const false;                // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
-        _5 = move _1;                    // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
-        goto -> bb12;                    // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
-    }
-
-    bb2: {
-        goto -> bb3;                     // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
-    }
-
-    bb3: {
-        StorageDead(_5);                 // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
-        _0 = const ();                   // scope 0 at $DIR/issue_41110.rs:+0:15: +5:2
-        drop(_2) -> [return: bb4, unwind: bb9]; // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2
-    }
-
-    bb4: {
-        StorageDead(_2);                 // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2
-        goto -> bb5;                     // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
-    }
-
-    bb5: {
-        _6 = const false;                // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
-        StorageDead(_1);                 // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
-        return;                          // scope 0 at $DIR/issue_41110.rs:+5:2: +5:2
-    }
-
-    bb6 (cleanup): {
-        goto -> bb8;                     // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
-    }
-
-    bb7 (cleanup): {
-        goto -> bb8;                     // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12
-    }
-
-    bb8 (cleanup): {
-        goto -> bb9;                     // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2
-    }
-
-    bb9 (cleanup): {
-        goto -> bb14;                    // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
-    }
-
-    bb10 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue_41110.rs:+0:1: +5:2
-    }
-
-    bb11 (cleanup): {
-        _2 = move _5;                    // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
-        goto -> bb6;                     // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
-    }
-
-    bb12: {
-        _2 = move _5;                    // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
-        goto -> bb2;                     // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
-    }
-
-    bb13 (cleanup): {
-        drop(_1) -> bb10;                // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
-    }
-
-    bb14 (cleanup): {
-        switchInt(_6) -> [0: bb10, otherwise: bb13]; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
-    }
-}
diff --git a/tests/mir-opt/issue_41110.test.ElaborateDrops.diff b/tests/mir-opt/issue_41110.test.ElaborateDrops.diff
new file mode 100644
index 000000000..79e3d073b
--- /dev/null
+++ b/tests/mir-opt/issue_41110.test.ElaborateDrops.diff
@@ -0,0 +1,109 @@
+- // MIR for `test` before ElaborateDrops
++ // MIR for `test` after ElaborateDrops
+  
+  fn test() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/issue_41110.rs:+0:15: +0:15
+      let _1: S;                           // in scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+      let _3: ();                          // in scope 0 at $DIR/issue_41110.rs:+3:5: +3:12
+      let mut _4: S;                       // in scope 0 at $DIR/issue_41110.rs:+3:10: +3:11
+      let mut _5: S;                       // in scope 0 at $DIR/issue_41110.rs:+4:9: +4:10
++     let mut _6: bool;                    // in scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
+      scope 1 {
+          debug u => _1;                   // in scope 1 at $DIR/issue_41110.rs:+1:9: +1:10
+          let mut _2: S;                   // in scope 1 at $DIR/issue_41110.rs:+2:9: +2:14
+          scope 2 {
+              debug v => _2;               // in scope 2 at $DIR/issue_41110.rs:+2:9: +2:14
+          }
+      }
+  
+      bb0: {
++         _6 = const false;                // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
+          StorageLive(_1);                 // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10
++         _6 = const true;                 // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+          _1 = S;                          // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14
+          StorageLive(_2);                 // scope 1 at $DIR/issue_41110.rs:+2:9: +2:14
+          _2 = S;                          // scope 1 at $DIR/issue_41110.rs:+2:17: +2:18
+          StorageLive(_3);                 // scope 2 at $DIR/issue_41110.rs:+3:5: +3:12
+          StorageLive(_4);                 // scope 2 at $DIR/issue_41110.rs:+3:10: +3:11
+          _4 = move _2;                    // scope 2 at $DIR/issue_41110.rs:+3:10: +3:11
+          _3 = std::mem::drop::<S>(move _4) -> [return: bb1, unwind: bb7]; // scope 2 at $DIR/issue_41110.rs:+3:5: +3:12
+                                           // mir::Constant
+                                           // + span: $DIR/issue_41110.rs:17:5: 17:9
+                                           // + literal: Const { ty: fn(S) {std::mem::drop::<S>}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          StorageDead(_4);                 // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12
+          StorageDead(_3);                 // scope 2 at $DIR/issue_41110.rs:+3:12: +3:13
+          StorageLive(_5);                 // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
++         _6 = const false;                // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
+          _5 = move _1;                    // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
+-         replace(_2 <- move _5) -> [return: bb2, unwind: bb6]; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
++         goto -> bb12;                    // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
+      }
+  
+      bb2: {
+-         drop(_5) -> [return: bb3, unwind: bb8]; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
++         goto -> bb3;                     // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
+      }
+  
+      bb3: {
+          StorageDead(_5);                 // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
+          _0 = const ();                   // scope 0 at $DIR/issue_41110.rs:+0:15: +5:2
+          drop(_2) -> [return: bb4, unwind: bb9]; // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2
+      }
+  
+      bb4: {
+          StorageDead(_2);                 // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2
+-         drop(_1) -> bb5;                 // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
++         goto -> bb5;                     // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
+      }
+  
+      bb5: {
++         _6 = const false;                // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
+          StorageDead(_1);                 // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
+          return;                          // scope 0 at $DIR/issue_41110.rs:+5:2: +5:2
+      }
+  
+      bb6 (cleanup): {
+          drop(_5) -> bb8;                 // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10
+      }
+  
+      bb7 (cleanup): {
+-         drop(_4) -> bb8;                 // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12
++         goto -> bb8;                     // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12
+      }
+  
+      bb8 (cleanup): {
+-         drop(_2) -> bb9;                 // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2
++         goto -> bb9;                     // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2
+      }
+  
+      bb9 (cleanup): {
+-         drop(_1) -> bb10;                // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
++         goto -> bb14;                    // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
+      }
+  
+      bb10 (cleanup): {
+          resume;                          // scope 0 at $DIR/issue_41110.rs:+0:1: +5:2
++     }
++ 
++     bb11 (cleanup): {
++         _2 = move _5;                    // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
++         goto -> bb10;                    // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
++     }
++ 
++     bb12: {
++         _2 = move _5;                    // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
++         goto -> bb2;                     // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6
++     }
++ 
++     bb13 (cleanup): {
++         drop(_1) -> bb10;                // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
++     }
++ 
++     bb14 (cleanup): {
++         switchInt(_6) -> [0: bb10, otherwise: bb13]; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2
+      }
+  }
+  
diff --git a/tests/mir-opt/issue_41888.main.ElaborateDrops.after.mir b/tests/mir-opt/issue_41888.main.ElaborateDrops.after.mir
deleted file mode 100644
index 005042732..000000000
--- a/tests/mir-opt/issue_41888.main.ElaborateDrops.after.mir
+++ /dev/null
@@ -1,152 +0,0 @@
-// MIR for `main` after ElaborateDrops
-
-fn main() -> () {
-    let mut _0: ();                      // return place in scope 0 at $DIR/issue_41888.rs:+0:11: +0:11
-    let _1: E;                           // in scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
-    let mut _2: bool;                    // in scope 0 at $DIR/issue_41888.rs:+2:8: +2:14
-    let mut _3: E;                       // in scope 0 at $DIR/issue_41888.rs:+3:13: +3:20
-    let mut _4: K;                       // in scope 0 at $DIR/issue_41888.rs:+3:18: +3:19
-    let mut _5: isize;                   // in scope 0 at $DIR/issue_41888.rs:+4:16: +4:24
-    let mut _7: bool;                    // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    let mut _8: bool;                    // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    let mut _9: bool;                    // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    let mut _10: isize;                  // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    let mut _11: isize;                  // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    scope 1 {
-        debug e => _1;                   // in scope 1 at $DIR/issue_41888.rs:+1:9: +1:10
-        scope 2 {
-            debug _k => _6;              // in scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
-            let _6: K;                   // in scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
-        }
-    }
-
-    bb0: {
-        _9 = const false;                // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
-        _7 = const false;                // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
-        _8 = const false;                // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
-        StorageLive(_1);                 // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
-        StorageLive(_2);                 // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14
-        _2 = cond() -> [return: bb1, unwind: bb11]; // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14
-                                         // mir::Constant
-                                         // + span: $DIR/issue_41888.rs:8:8: 8:12
-                                         // + literal: Const { ty: fn() -> bool {cond}, val: Value(<ZST>) }
-    }
-
-    bb1: {
-        switchInt(move _2) -> [0: bb7, otherwise: bb2]; // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14
-    }
-
-    bb2: {
-        StorageLive(_3);                 // scope 1 at $DIR/issue_41888.rs:+3:13: +3:20
-        StorageLive(_4);                 // scope 1 at $DIR/issue_41888.rs:+3:18: +3:19
-        _4 = K;                          // scope 1 at $DIR/issue_41888.rs:+3:18: +3:19
-        _3 = E::F(move _4);              // scope 1 at $DIR/issue_41888.rs:+3:13: +3:20
-        StorageDead(_4);                 // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
-        goto -> bb14;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-    }
-
-    bb3: {
-        goto -> bb4;                     // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
-    }
-
-    bb4: {
-        StorageDead(_3);                 // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
-        _5 = discriminant(_1);           // scope 2 at $DIR/issue_41888.rs:+4:16: +4:24
-        switchInt(move _5) -> [0: bb5, otherwise: bb6]; // scope 2 at $DIR/issue_41888.rs:+4:16: +4:24
-    }
-
-    bb5: {
-        StorageLive(_6);                 // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
-        _9 = const false;                // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
-        _6 = move ((_1 as F).0: K);      // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
-        _0 = const ();                   // scope 2 at $DIR/issue_41888.rs:+4:29: +7:10
-        StorageDead(_6);                 // scope 1 at $DIR/issue_41888.rs:+7:9: +7:10
-        goto -> bb8;                     // scope 1 at $DIR/issue_41888.rs:+4:9: +7:10
-    }
-
-    bb6: {
-        _0 = const ();                   // scope 1 at $DIR/issue_41888.rs:+7:10: +7:10
-        goto -> bb8;                     // scope 1 at $DIR/issue_41888.rs:+4:9: +7:10
-    }
-
-    bb7: {
-        _0 = const ();                   // scope 1 at $DIR/issue_41888.rs:+8:6: +8:6
-        goto -> bb8;                     // scope 1 at $DIR/issue_41888.rs:+2:5: +8:6
-    }
-
-    bb8: {
-        StorageDead(_2);                 // scope 1 at $DIR/issue_41888.rs:+8:5: +8:6
-        goto -> bb20;                    // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    }
-
-    bb9: {
-        _7 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-        _8 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-        _9 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-        StorageDead(_1);                 // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-        return;                          // scope 0 at $DIR/issue_41888.rs:+9:2: +9:2
-    }
-
-    bb10 (cleanup): {
-        goto -> bb11;                    // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
-    }
-
-    bb11 (cleanup): {
-        goto -> bb12;                    // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    }
-
-    bb12 (cleanup): {
-        resume;                          // scope 0 at $DIR/issue_41888.rs:+0:1: +9:2
-    }
-
-    bb13 (cleanup): {
-        _7 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-        _8 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-        _9 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-        _1 = move _3;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-        goto -> bb10;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-    }
-
-    bb14: {
-        _7 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-        _8 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-        _9 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-        _1 = move _3;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-        goto -> bb3;                     // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
-    }
-
-    bb15: {
-        _7 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-        goto -> bb9;                     // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    }
-
-    bb16 (cleanup): {
-        goto -> bb12;                    // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    }
-
-    bb17: {
-        drop(_1) -> [return: bb15, unwind: bb12]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    }
-
-    bb18 (cleanup): {
-        drop(_1) -> bb12;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    }
-
-    bb19: {
-        _10 = discriminant(_1);          // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-        switchInt(move _10) -> [0: bb15, otherwise: bb17]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    }
-
-    bb20: {
-        switchInt(_7) -> [0: bb15, otherwise: bb19]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    }
-
-    bb21 (cleanup): {
-        _11 = discriminant(_1);          // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-        switchInt(move _11) -> [0: bb16, otherwise: bb18]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    }
-
-    bb22 (cleanup): {
-        switchInt(_7) -> [0: bb12, otherwise: bb21]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
-    }
-}
diff --git a/tests/mir-opt/issue_41888.main.ElaborateDrops.diff b/tests/mir-opt/issue_41888.main.ElaborateDrops.diff
new file mode 100644
index 000000000..257f0b1e6
--- /dev/null
+++ b/tests/mir-opt/issue_41888.main.ElaborateDrops.diff
@@ -0,0 +1,158 @@
+- // MIR for `main` before ElaborateDrops
++ // MIR for `main` after ElaborateDrops
+  
+  fn main() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/issue_41888.rs:+0:11: +0:11
+      let _1: E;                           // in scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
+      let mut _2: bool;                    // in scope 0 at $DIR/issue_41888.rs:+2:8: +2:14
+      let mut _3: E;                       // in scope 0 at $DIR/issue_41888.rs:+3:13: +3:20
+      let mut _4: K;                       // in scope 0 at $DIR/issue_41888.rs:+3:18: +3:19
+      let mut _5: isize;                   // in scope 0 at $DIR/issue_41888.rs:+4:16: +4:24
++     let mut _7: bool;                    // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     let mut _8: bool;                    // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     let mut _9: bool;                    // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     let mut _10: isize;                  // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     let mut _11: isize;                  // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+      scope 1 {
+          debug e => _1;                   // in scope 1 at $DIR/issue_41888.rs:+1:9: +1:10
+          scope 2 {
+              debug _k => _6;              // in scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
+              let _6: K;                   // in scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
+          }
+      }
+  
+      bb0: {
++         _9 = const false;                // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
++         _7 = const false;                // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
++         _8 = const false;                // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
+          StorageLive(_1);                 // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10
+          StorageLive(_2);                 // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14
+          _2 = cond() -> [return: bb1, unwind: bb11]; // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14
+                                           // mir::Constant
+                                           // + span: $DIR/issue_41888.rs:8:8: 8:12
+                                           // + literal: Const { ty: fn() -> bool {cond}, val: Value(<ZST>) }
+      }
+  
+      bb1: {
+          switchInt(move _2) -> [0: bb7, otherwise: bb2]; // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14
+      }
+  
+      bb2: {
+          StorageLive(_3);                 // scope 1 at $DIR/issue_41888.rs:+3:13: +3:20
+          StorageLive(_4);                 // scope 1 at $DIR/issue_41888.rs:+3:18: +3:19
+          _4 = K;                          // scope 1 at $DIR/issue_41888.rs:+3:18: +3:19
+          _3 = E::F(move _4);              // scope 1 at $DIR/issue_41888.rs:+3:13: +3:20
+          StorageDead(_4);                 // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
+-         replace(_1 <- move _3) -> [return: bb3, unwind: bb10]; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++         goto -> bb14;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
+      }
+  
+      bb3: {
+-         drop(_3) -> [return: bb4, unwind: bb11]; // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
++         goto -> bb4;                     // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
+      }
+  
+      bb4: {
+          StorageDead(_3);                 // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
+          _5 = discriminant(_1);           // scope 2 at $DIR/issue_41888.rs:+4:16: +4:24
+          switchInt(move _5) -> [0: bb5, otherwise: bb6]; // scope 2 at $DIR/issue_41888.rs:+4:16: +4:24
+      }
+  
+      bb5: {
+          StorageLive(_6);                 // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
++         _9 = const false;                // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
+          _6 = move ((_1 as F).0: K);      // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23
+          _0 = const ();                   // scope 2 at $DIR/issue_41888.rs:+4:29: +7:10
+          StorageDead(_6);                 // scope 1 at $DIR/issue_41888.rs:+7:9: +7:10
+          goto -> bb8;                     // scope 1 at $DIR/issue_41888.rs:+4:9: +7:10
+      }
+  
+      bb6: {
+          _0 = const ();                   // scope 1 at $DIR/issue_41888.rs:+7:10: +7:10
+          goto -> bb8;                     // scope 1 at $DIR/issue_41888.rs:+4:9: +7:10
+      }
+  
+      bb7: {
+          _0 = const ();                   // scope 1 at $DIR/issue_41888.rs:+8:6: +8:6
+          goto -> bb8;                     // scope 1 at $DIR/issue_41888.rs:+2:5: +8:6
+      }
+  
+      bb8: {
+          StorageDead(_2);                 // scope 1 at $DIR/issue_41888.rs:+8:5: +8:6
+-         drop(_1) -> bb9;                 // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++         goto -> bb20;                    // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+      }
+  
+      bb9: {
++         _7 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++         _8 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++         _9 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+          StorageDead(_1);                 // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+          return;                          // scope 0 at $DIR/issue_41888.rs:+9:2: +9:2
+      }
+  
+      bb10 (cleanup): {
+          drop(_3) -> bb11;                // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20
+      }
+  
+      bb11 (cleanup): {
+-         drop(_1) -> bb12;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++         goto -> bb12;                    // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+      }
+  
+      bb12 (cleanup): {
+          resume;                          // scope 0 at $DIR/issue_41888.rs:+0:1: +9:2
++     }
++ 
++     bb13 (cleanup): {
++         _7 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++         _8 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++         _9 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++         _1 = move _3;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++         goto -> bb12;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++     }
++ 
++     bb14: {
++         _7 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++         _8 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++         _9 = const true;                 // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++         _1 = move _3;                    // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++         goto -> bb3;                     // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10
++     }
++ 
++     bb15: {
++         _7 = const false;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++         goto -> bb9;                     // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     }
++ 
++     bb16 (cleanup): {
++         goto -> bb12;                    // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     }
++ 
++     bb17: {
++         drop(_1) -> [return: bb15, unwind: bb12]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     }
++ 
++     bb18 (cleanup): {
++         drop(_1) -> bb12;                // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     }
++ 
++     bb19: {
++         _10 = discriminant(_1);          // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++         switchInt(move _10) -> [0: bb15, otherwise: bb17]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     }
++ 
++     bb20: {
++         switchInt(_7) -> [0: bb15, otherwise: bb19]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     }
++ 
++     bb21 (cleanup): {
++         _11 = discriminant(_1);          // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++         switchInt(move _11) -> [0: bb16, otherwise: bb18]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
++     }
++ 
++     bb22 (cleanup): {
++         switchInt(_7) -> [0: bb12, otherwise: bb21]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2
+      }
+  }
+  
diff --git a/tests/mir-opt/issue_41888.rs b/tests/mir-opt/issue_41888.rs
index c1046c14d..0f10c0a1d 100644
--- a/tests/mir-opt/issue_41888.rs
+++ b/tests/mir-opt/issue_41888.rs
@@ -2,7 +2,7 @@
 // check that we clear the "ADT master drop flag" even when there are
 // no fields to be dropped.
 
-// EMIT_MIR issue_41888.main.ElaborateDrops.after.mir
+// EMIT_MIR issue_41888.main.ElaborateDrops.diff
 fn main() {
     let e;
     if cond() {
diff --git a/tests/mir-opt/issue_73223.main.SimplifyArmIdentity.diff b/tests/mir-opt/issue_73223.main.SimplifyArmIdentity.diff
deleted file mode 100644
index bf3bcfdb5..000000000
--- a/tests/mir-opt/issue_73223.main.SimplifyArmIdentity.diff
+++ /dev/null
@@ -1,156 +0,0 @@
-- // MIR for `main` before SimplifyArmIdentity
-+ // MIR for `main` after SimplifyArmIdentity
-  
-  fn main() -> () {
-      let mut _0: ();                      // return place in scope 0 at $DIR/issue_73223.rs:+0:11: +0:11
-      let _1: i32;                         // in scope 0 at $DIR/issue_73223.rs:+1:9: +1:14
-      let mut _2: std::option::Option<i32>; // in scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
-      let mut _3: isize;                   // in scope 0 at $DIR/issue_73223.rs:+2:9: +2:16
-      let _4: i32;                         // in scope 0 at $DIR/issue_73223.rs:+2:14: +2:15
-      let mut _6: i32;                     // in scope 0 at $DIR/issue_73223.rs:+6:22: +6:27
-      let mut _7: &i32;                    // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _8: &i32;                    // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _11: bool;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _12: bool;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _13: i32;                    // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _14: i32;                    // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let _16: !;                          // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _17: core::panicking::AssertKind; // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _18: &i32;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let _19: &i32;                       // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _20: &i32;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let _21: &i32;                       // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _22: std::option::Option<std::fmt::Arguments<'_>>; // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _24: &i32;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      let mut _25: &i32;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      scope 1 {
-          debug split => _1;               // in scope 1 at $DIR/issue_73223.rs:+1:9: +1:14
-          let _5: std::option::Option<i32>; // in scope 1 at $DIR/issue_73223.rs:+6:9: +6:14
-          scope 3 {
-              debug _prev => _5;           // in scope 3 at $DIR/issue_73223.rs:+6:9: +6:14
-              let _9: &i32;                // in scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-              let _10: &i32;               // in scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-              let mut _23: &i32;           // in scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-              scope 4 {
-                  debug left_val => _9;    // in scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                  debug right_val => _10;  // in scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                  let _15: core::panicking::AssertKind; // in scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                  scope 5 {
-                      debug kind => _15;   // in scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                  }
-              }
-          }
-      }
-      scope 2 {
-          debug v => _4;                   // in scope 2 at $DIR/issue_73223.rs:+2:14: +2:15
-      }
-  
-      bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/issue_73223.rs:+1:9: +1:14
-          StorageLive(_2);                 // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
-          Deinit(_2);                      // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
-          ((_2 as Some).0: i32) = const 1_i32; // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
-          discriminant(_2) = 1;            // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
-          _3 = const 1_isize;              // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
-          goto -> bb3;                     // scope 0 at $DIR/issue_73223.rs:+1:17: +1:30
-      }
-  
-      bb1: {
-          StorageDead(_2);                 // scope 0 at $DIR/issue_73223.rs:+4:6: +4:7
-          StorageDead(_1);                 // scope 0 at $DIR/issue_73223.rs:+8:1: +8:2
-          return;                          // scope 0 at $DIR/issue_73223.rs:+8:2: +8:2
-      }
-  
-      bb2: {
-          unreachable;                     // scope 0 at $DIR/issue_73223.rs:+1:23: +1:30
-      }
-  
-      bb3: {
-          StorageLive(_4);                 // scope 0 at $DIR/issue_73223.rs:+2:14: +2:15
-          _4 = ((_2 as Some).0: i32);      // scope 0 at $DIR/issue_73223.rs:+2:14: +2:15
-          _1 = _4;                         // scope 2 at $DIR/issue_73223.rs:+2:20: +2:21
-          StorageDead(_4);                 // scope 0 at $DIR/issue_73223.rs:+2:20: +2:21
-          StorageDead(_2);                 // scope 0 at $DIR/issue_73223.rs:+4:6: +4:7
-          StorageLive(_5);                 // scope 1 at $DIR/issue_73223.rs:+6:9: +6:14
-          StorageLive(_6);                 // scope 1 at $DIR/issue_73223.rs:+6:22: +6:27
-          _6 = _1;                         // scope 1 at $DIR/issue_73223.rs:+6:22: +6:27
-          Deinit(_5);                      // scope 1 at $DIR/issue_73223.rs:+6:17: +6:28
-          ((_5 as Some).0: i32) = move _6; // scope 1 at $DIR/issue_73223.rs:+6:17: +6:28
-          discriminant(_5) = 1;            // scope 1 at $DIR/issue_73223.rs:+6:17: +6:28
-          StorageDead(_6);                 // scope 1 at $DIR/issue_73223.rs:+6:27: +6:28
-          StorageLive(_24);                // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_25);                // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_7);                 // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _7 = &_1;                        // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_8);                 // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _23 = const _;                   // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                                           // mir::Constant
-                                           // + span: $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                                           // + literal: Const { ty: &i32, val: Unevaluated(main, [], Some(promoted[0])) }
-          _8 = _23;                        // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          Deinit(_24);                     // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          Deinit(_25);                     // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _24 = move _7;                   // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _25 = move _8;                   // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageDead(_8);                 // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageDead(_7);                 // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_9);                 // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _9 = _24;                        // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_10);                // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _10 = _25;                       // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_11);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_12);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_13);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _13 = (*_9);                     // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_14);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _14 = const 1_i32;               // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _12 = Eq(move _13, const 1_i32); // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageDead(_14);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageDead(_13);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _11 = Not(move _12);             // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageDead(_12);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          switchInt(move _11) -> [0: bb5, otherwise: bb4]; // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-      }
-  
-      bb4: {
-          StorageLive(_15);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          Deinit(_15);                     // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          discriminant(_15) = 0;           // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_16);                // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_17);                // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _17 = const core::panicking::AssertKind::Eq; // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                                           // mir::Constant
-                                           // + span: $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                                           // + literal: Const { ty: core::panicking::AssertKind, val: Value(Scalar(0x00)) }
-          StorageLive(_18);                // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_19);                // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _19 = _9;                        // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _18 = _19;                       // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_20);                // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_21);                // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _21 = _10;                       // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _20 = _21;                       // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageLive(_22);                // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          Deinit(_22);                     // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          discriminant(_22) = 0;           // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          _16 = core::panicking::assert_failed::<i32, i32>(const core::panicking::AssertKind::Eq, move _18, move _20, move _22); // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                                           // mir::Constant
-                                           // + span: $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                                           // + literal: Const { ty: for<'a, 'b, 'c> fn(core::panicking::AssertKind, &'a i32, &'b i32, Option<Arguments<'c>>) -> ! {core::panicking::assert_failed::<i32, i32>}, val: Value(<ZST>) }
-                                           // mir::Constant
-                                           // + span: $SRC_DIR/core/src/macros/mod.rs:LL:COL
-                                           // + literal: Const { ty: core::panicking::AssertKind, val: Value(Scalar(0x00)) }
-      }
-  
-      bb5: {
-          StorageDead(_11);                // scope 4 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageDead(_10);                // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageDead(_9);                 // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageDead(_24);                // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageDead(_25);                // scope 3 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-          StorageDead(_5);                 // scope 1 at $DIR/issue_73223.rs:+8:1: +8:2
-          StorageDead(_1);                 // scope 0 at $DIR/issue_73223.rs:+8:1: +8:2
-          return;                          // scope 0 at $DIR/issue_73223.rs:+8:2: +8:2
-      }
-  }
-  
diff --git a/tests/mir-opt/issue_73223.rs b/tests/mir-opt/issue_73223.rs
deleted file mode 100644
index be114cab7..000000000
--- a/tests/mir-opt/issue_73223.rs
+++ /dev/null
@@ -1,12 +0,0 @@
-fn main() {
-    let split = match Some(1) {
-        Some(v) => v,
-        None => return,
-    };
-
-    let _prev = Some(split);
-    assert_eq!(split, 1);
-}
-
-
-// EMIT_MIR issue_73223.main.SimplifyArmIdentity.diff
diff --git a/tests/mir-opt/issue_76432.rs b/tests/mir-opt/issue_76432.rs
index c8b405ca8..fbbfd4ceb 100644
--- a/tests/mir-opt/issue_76432.rs
+++ b/tests/mir-opt/issue_76432.rs
@@ -1,3 +1,4 @@
+// compile-flags: -Zmir-enable-passes=-NormalizeArrayLen
 // Check that we do not insert StorageDead at each target if StorageDead was never seen
 
 // EMIT_MIR issue_76432.test.SimplifyComparisonIntegral.diff
diff --git a/tests/mir-opt/issue_76432.test.SimplifyComparisonIntegral.diff b/tests/mir-opt/issue_76432.test.SimplifyComparisonIntegral.diff
index c24543dae..cc4f7cc06 100644
--- a/tests/mir-opt/issue_76432.test.SimplifyComparisonIntegral.diff
+++ b/tests/mir-opt/issue_76432.test.SimplifyComparisonIntegral.diff
@@ -29,24 +29,10 @@
   
       bb0: {
           StorageLive(_2);                 // scope 0 at $DIR/issue_76432.rs:+1:9: +1:10
-          StorageLive(_3);                 // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
-          StorageLive(_4);                 // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
           StorageLive(_5);                 // scope 0 at $DIR/issue_76432.rs:+1:20: +1:29
-          StorageLive(_6);                 // scope 0 at $DIR/issue_76432.rs:+1:21: +1:22
-          _6 = _1;                         // scope 0 at $DIR/issue_76432.rs:+1:21: +1:22
-          StorageLive(_7);                 // scope 0 at $DIR/issue_76432.rs:+1:24: +1:25
-          _7 = _1;                         // scope 0 at $DIR/issue_76432.rs:+1:24: +1:25
-          StorageLive(_8);                 // scope 0 at $DIR/issue_76432.rs:+1:27: +1:28
-          _8 = _1;                         // scope 0 at $DIR/issue_76432.rs:+1:27: +1:28
-          _5 = [move _6, move _7, move _8]; // scope 0 at $DIR/issue_76432.rs:+1:20: +1:29
-          StorageDead(_8);                 // scope 0 at $DIR/issue_76432.rs:+1:28: +1:29
-          StorageDead(_7);                 // scope 0 at $DIR/issue_76432.rs:+1:28: +1:29
-          StorageDead(_6);                 // scope 0 at $DIR/issue_76432.rs:+1:28: +1:29
+          _5 = [_1, _1, _1];               // scope 0 at $DIR/issue_76432.rs:+1:20: +1:29
           _4 = &_5;                        // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
-          _3 = _4;                         // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
-          _2 = move _3 as &[T] (Pointer(Unsize)); // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
-          StorageDead(_3);                 // scope 0 at $DIR/issue_76432.rs:+1:28: +1:29
-          StorageDead(_4);                 // scope 0 at $DIR/issue_76432.rs:+1:29: +1:30
+          _2 = _4 as &[T] (Pointer(Unsize)); // scope 0 at $DIR/issue_76432.rs:+1:19: +1:29
           _9 = Len((*_2));                 // scope 1 at $DIR/issue_76432.rs:+3:9: +3:33
           _10 = const 3_usize;             // scope 1 at $DIR/issue_76432.rs:+3:9: +3:33
 -         _11 = Eq(move _9, const 3_usize); // scope 1 at $DIR/issue_76432.rs:+3:9: +3:33
diff --git a/tests/mir-opt/issues/issue_59352.num_to_digit.PreCodegen.after.mir b/tests/mir-opt/issues/issue_59352.num_to_digit.PreCodegen.after.mir
index c17d221f8..291fc5063 100644
--- a/tests/mir-opt/issues/issue_59352.num_to_digit.PreCodegen.after.mir
+++ b/tests/mir-opt/issues/issue_59352.num_to_digit.PreCodegen.after.mir
@@ -5,15 +5,14 @@ fn num_to_digit(_1: char) -> u32 {
     let mut _0: u32;                     // return place in scope 0 at $DIR/issue_59352.rs:+0:35: +0:38
     let mut _2: std::option::Option<u32>; // in scope 0 at $DIR/issue_59352.rs:+2:26: +2:41
     let mut _3: u32;                     // in scope 0 at $DIR/issue_59352.rs:+2:12: +2:23
-    let mut _9: isize;                   // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
     scope 1 (inlined char::methods::<impl char>::is_digit) { // at $DIR/issue_59352.rs:14:12: 14:23
         debug self => _1;                // in scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         debug radix => _3;               // in scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         let mut _4: &std::option::Option<u32>; // in scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         let _5: std::option::Option<u32>; // in scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
-        let mut _6: char;                // in scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         scope 2 (inlined Option::<u32>::is_some) { // at $SRC_DIR/core/src/char/methods.rs:LL:COL
             debug self => _4;            // in scope 2 at $SRC_DIR/core/src/option.rs:LL:COL
+            let mut _6: isize;           // in scope 2 at $SRC_DIR/core/src/option.rs:LL:COL
         }
     }
     scope 3 (inlined #[track_caller] Option::<u32>::unwrap) { // at $DIR/issue_59352.rs:14:42: 14:50
@@ -29,9 +28,7 @@ fn num_to_digit(_1: char) -> u32 {
         StorageLive(_3);                 // scope 0 at $DIR/issue_59352.rs:+2:12: +2:23
         StorageLive(_4);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         StorageLive(_5);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
-        StorageLive(_6);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
-        _6 = _1;                         // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
-        _5 = char::methods::<impl char>::to_digit(move _6, const 8_u32) -> bb5; // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
+        _5 = char::methods::<impl char>::to_digit(_1, const 8_u32) -> bb5; // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
                                          // mir::Constant
                                          // + span: $SRC_DIR/core/src/char/methods.rs:LL:COL
                                          // + literal: Const { ty: fn(char, u32) -> Option<u32> {char::methods::<impl char>::to_digit}, val: Value(<ZST>) }
@@ -39,7 +36,7 @@ fn num_to_digit(_1: char) -> u32 {
 
     bb1: {
         StorageLive(_2);                 // scope 0 at $DIR/issue_59352.rs:+2:26: +2:41
-        _2 = char::methods::<impl char>::to_digit(move _1, const 8_u32) -> bb2; // scope 0 at $DIR/issue_59352.rs:+2:26: +2:41
+        _2 = char::methods::<impl char>::to_digit(_1, const 8_u32) -> bb2; // scope 0 at $DIR/issue_59352.rs:+2:26: +2:41
                                          // mir::Constant
                                          // + span: $DIR/issue_59352.rs:14:30: 14:38
                                          // + literal: Const { ty: fn(char, u32) -> Option<u32> {char::methods::<impl char>::to_digit}, val: Value(<ZST>) }
@@ -61,12 +58,11 @@ fn num_to_digit(_1: char) -> u32 {
 
     bb5: {
         _4 = &_5;                        // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
-        StorageDead(_6);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
-        _9 = discriminant((*_4));        // scope 2 at $SRC_DIR/core/src/option.rs:LL:COL
+        _6 = discriminant((*_4));        // scope 2 at $SRC_DIR/core/src/option.rs:LL:COL
         StorageDead(_4);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         StorageDead(_5);                 // scope 1 at $SRC_DIR/core/src/char/methods.rs:LL:COL
         StorageDead(_3);                 // scope 0 at $DIR/issue_59352.rs:+2:12: +2:23
-        switchInt(move _9) -> [1: bb1, otherwise: bb3]; // scope 0 at $DIR/issue_59352.rs:+2:8: +2:23
+        switchInt(move _6) -> [1: bb1, otherwise: bb3]; // scope 0 at $DIR/issue_59352.rs:+2:8: +2:23
     }
 
     bb6: {
diff --git a/tests/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff b/tests/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff
index 938047803..bcda12880 100644
--- a/tests/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff
+++ b/tests/mir-opt/issues/issue_75439.foo.MatchBranchSimplification.diff
@@ -67,17 +67,14 @@
   
       bb7: {
           StorageDead(_6);                 // scope 4 at $DIR/issue_75439.rs:+5:35: +5:36
-          Deinit(_0);                      // scope 3 at $DIR/issue_75439.rs:+5:9: +5:39
-          ((_0 as Some).0: [u8; 4]) = move _5; // scope 3 at $DIR/issue_75439.rs:+5:9: +5:39
-          discriminant(_0) = 1;            // scope 3 at $DIR/issue_75439.rs:+5:9: +5:39
+          _0 = Option::<[u8; 4]>::Some(move _5); // scope 3 at $DIR/issue_75439.rs:+5:9: +5:39
           StorageDead(_5);                 // scope 3 at $DIR/issue_75439.rs:+5:38: +5:39
           StorageDead(_4);                 // scope 1 at $DIR/issue_75439.rs:+6:5: +6:6
           goto -> bb9;                     // scope 1 at $DIR/issue_75439.rs:+4:5: +8:6
       }
   
       bb8: {
-          Deinit(_0);                      // scope 1 at $DIR/issue_75439.rs:+7:9: +7:13
-          discriminant(_0) = 0;            // scope 1 at $DIR/issue_75439.rs:+7:9: +7:13
+          _0 = Option::<[u8; 4]>::None;    // scope 1 at $DIR/issue_75439.rs:+7:9: +7:13
           goto -> bb9;                     // scope 1 at $DIR/issue_75439.rs:+4:5: +8:6
       }
   
diff --git a/tests/mir-opt/lower_array_len.array_bound.NormalizeArrayLen.diff b/tests/mir-opt/lower_array_len.array_bound.NormalizeArrayLen.diff
index 9bc7060e9..59de067f4 100644
--- a/tests/mir-opt/lower_array_len.array_bound.NormalizeArrayLen.diff
+++ b/tests/mir-opt/lower_array_len.array_bound.NormalizeArrayLen.diff
@@ -13,7 +13,6 @@
       let _8: usize;                       // in scope 0 at $DIR/lower_array_len.rs:+2:15: +2:20
       let mut _9: usize;                   // in scope 0 at $DIR/lower_array_len.rs:+2:9: +2:21
       let mut _10: bool;                   // in scope 0 at $DIR/lower_array_len.rs:+2:9: +2:21
-+     let mut _11: &[u8; N];               // in scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
   
       bb0: {
           StorageLive(_3);                 // scope 0 at $DIR/lower_array_len.rs:+1:8: +1:27
@@ -23,13 +22,10 @@
           StorageLive(_6);                 // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
           StorageLive(_7);                 // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
           _7 = &(*_2);                     // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
-+         StorageLive(_11);                // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
-+         _11 = _7;                        // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
           _6 = move _7 as &[u8] (Pointer(Unsize)); // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
           StorageDead(_7);                 // scope 0 at $DIR/lower_array_len.rs:+1:20: +1:21
 -         _5 = Len((*_6));                 // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
-+         _5 = Len((*_11));                // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
-+         StorageDead(_11);                // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
++         _5 = const N;                    // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
           goto -> bb1;                     // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
       }
   
diff --git a/tests/mir-opt/lower_array_len.array_bound_mut.NormalizeArrayLen.diff b/tests/mir-opt/lower_array_len.array_bound_mut.NormalizeArrayLen.diff
index cf427cfd1..17574b1b6 100644
--- a/tests/mir-opt/lower_array_len.array_bound_mut.NormalizeArrayLen.diff
+++ b/tests/mir-opt/lower_array_len.array_bound_mut.NormalizeArrayLen.diff
@@ -16,7 +16,6 @@
       let _11: usize;                      // in scope 0 at $DIR/lower_array_len.rs:+4:15: +4:16
       let mut _12: usize;                  // in scope 0 at $DIR/lower_array_len.rs:+4:9: +4:17
       let mut _13: bool;                   // in scope 0 at $DIR/lower_array_len.rs:+4:9: +4:17
-+     let mut _14: &[u8; N];               // in scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
   
       bb0: {
           StorageLive(_3);                 // scope 0 at $DIR/lower_array_len.rs:+1:8: +1:27
@@ -26,13 +25,10 @@
           StorageLive(_6);                 // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
           StorageLive(_7);                 // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
           _7 = &(*_2);                     // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
-+         StorageLive(_14);                // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
-+         _14 = _7;                        // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
           _6 = move _7 as &[u8] (Pointer(Unsize)); // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
           StorageDead(_7);                 // scope 0 at $DIR/lower_array_len.rs:+1:20: +1:21
 -         _5 = Len((*_6));                 // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
-+         _5 = Len((*_14));                // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
-+         StorageDead(_14);                // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
++         _5 = const N;                    // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
           goto -> bb1;                     // scope 0 at $DIR/lower_array_len.rs:+1:16: +1:27
       }
   
diff --git a/tests/mir-opt/lower_array_len.array_len.NormalizeArrayLen.diff b/tests/mir-opt/lower_array_len.array_len.NormalizeArrayLen.diff
index 3ed68f5f7..66feff62f 100644
--- a/tests/mir-opt/lower_array_len.array_len.NormalizeArrayLen.diff
+++ b/tests/mir-opt/lower_array_len.array_len.NormalizeArrayLen.diff
@@ -6,19 +6,15 @@
       let mut _0: usize;                   // return place in scope 0 at $DIR/lower_array_len.rs:+0:52: +0:57
       let mut _2: &[u8];                   // in scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
       let mut _3: &[u8; N];                // in scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
-+     let mut _4: &[u8; N];                // in scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
   
       bb0: {
           StorageLive(_2);                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
           StorageLive(_3);                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
           _3 = &(*_1);                     // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
-+         StorageLive(_4);                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
-+         _4 = _3;                         // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
           _2 = move _3 as &[u8] (Pointer(Unsize)); // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
           StorageDead(_3);                 // scope 0 at $DIR/lower_array_len.rs:+1:7: +1:8
 -         _0 = Len((*_2));                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
-+         _0 = Len((*_4));                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
-+         StorageDead(_4);                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
++         _0 = const N;                    // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
           goto -> bb1;                     // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
       }
   
diff --git a/tests/mir-opt/lower_array_len.array_len_by_value.NormalizeArrayLen.diff b/tests/mir-opt/lower_array_len.array_len_by_value.NormalizeArrayLen.diff
index f0e0cdcfd..c0a277edc 100644
--- a/tests/mir-opt/lower_array_len.array_len_by_value.NormalizeArrayLen.diff
+++ b/tests/mir-opt/lower_array_len.array_len_by_value.NormalizeArrayLen.diff
@@ -6,19 +6,15 @@
       let mut _0: usize;                   // return place in scope 0 at $DIR/lower_array_len.rs:+0:60: +0:65
       let mut _2: &[u8];                   // in scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
       let mut _3: &[u8; N];                // in scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
-+     let mut _4: &[u8; N];                // in scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
   
       bb0: {
           StorageLive(_2);                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
           StorageLive(_3);                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
           _3 = &_1;                        // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
-+         StorageLive(_4);                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
-+         _4 = _3;                         // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
           _2 = move _3 as &[u8] (Pointer(Unsize)); // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
           StorageDead(_3);                 // scope 0 at $DIR/lower_array_len.rs:+1:7: +1:8
 -         _0 = Len((*_2));                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
-+         _0 = Len((*_4));                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
-+         StorageDead(_4);                 // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
++         _0 = const N;                    // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
           goto -> bb1;                     // scope 0 at $DIR/lower_array_len.rs:+1:5: +1:14
       }
   
diff --git a/tests/mir-opt/lower_array_len.array_len_raw.NormalizeArrayLen.diff b/tests/mir-opt/lower_array_len.array_len_raw.NormalizeArrayLen.diff
new file mode 100644
index 000000000..8b35fd57f
--- /dev/null
+++ b/tests/mir-opt/lower_array_len.array_len_raw.NormalizeArrayLen.diff
@@ -0,0 +1,50 @@
+- // MIR for `array_len_raw` before NormalizeArrayLen
++ // MIR for `array_len_raw` after NormalizeArrayLen
+  
+  fn array_len_raw(_1: [u8; N]) -> usize {
+      debug arr => _1;                     // in scope 0 at $DIR/lower_array_len.rs:+0:38: +0:41
+      let mut _0: usize;                   // return place in scope 0 at $DIR/lower_array_len.rs:+0:55: +0:60
+      let _2: &[u8];                       // in scope 0 at $DIR/lower_array_len.rs:+1:9: +1:12
+      let mut _3: &[u8; N];                // in scope 0 at $DIR/lower_array_len.rs:+1:21: +1:25
+      let _4: &[u8; N];                    // in scope 0 at $DIR/lower_array_len.rs:+1:21: +1:25
+      let mut _6: &[u8];                   // in scope 0 at $DIR/lower_array_len.rs:+3:5: +3:27
+      let _7: &[u8];                       // in scope 0 at $DIR/lower_array_len.rs:+3:14: +3:19
+      scope 1 {
+          debug arr => _2;                 // in scope 1 at $DIR/lower_array_len.rs:+1:9: +1:12
+          let _5: *const [u8];             // in scope 1 at $DIR/lower_array_len.rs:+2:9: +2:12
+          scope 2 {
+              debug arr => _5;             // in scope 2 at $DIR/lower_array_len.rs:+2:9: +2:12
+              scope 3 {
+              }
+          }
+      }
+  
+      bb0: {
+          StorageLive(_2);                 // scope 0 at $DIR/lower_array_len.rs:+1:9: +1:12
+          StorageLive(_3);                 // scope 0 at $DIR/lower_array_len.rs:+1:21: +1:25
+          StorageLive(_4);                 // scope 0 at $DIR/lower_array_len.rs:+1:21: +1:25
+          _4 = &_1;                        // scope 0 at $DIR/lower_array_len.rs:+1:21: +1:25
+          _3 = &(*_4);                     // scope 0 at $DIR/lower_array_len.rs:+1:21: +1:25
+          _2 = move _3 as &[u8] (Pointer(Unsize)); // scope 0 at $DIR/lower_array_len.rs:+1:21: +1:25
+          StorageDead(_3);                 // scope 0 at $DIR/lower_array_len.rs:+1:24: +1:25
+          StorageDead(_4);                 // scope 0 at $DIR/lower_array_len.rs:+1:25: +1:26
+          StorageLive(_5);                 // scope 1 at $DIR/lower_array_len.rs:+2:9: +2:12
+          _5 = &raw const (*_2);           // scope 1 at $SRC_DIR/core/src/ptr/mod.rs:LL:COL
+          StorageLive(_6);                 // scope 2 at $DIR/lower_array_len.rs:+3:5: +3:27
+          StorageLive(_7);                 // scope 2 at $DIR/lower_array_len.rs:+3:14: +3:19
+          _7 = &(*_5);                     // scope 3 at $DIR/lower_array_len.rs:+3:14: +3:19
+          _6 = &(*_7);                     // scope 2 at $DIR/lower_array_len.rs:+3:5: +3:27
+-         _0 = Len((*_6));                 // scope 2 at $DIR/lower_array_len.rs:+3:5: +3:27
++         _0 = const N;                    // scope 2 at $DIR/lower_array_len.rs:+3:5: +3:27
+          goto -> bb1;                     // scope 2 at $DIR/lower_array_len.rs:+3:5: +3:27
+      }
+  
+      bb1: {
+          StorageDead(_6);                 // scope 2 at $DIR/lower_array_len.rs:+3:26: +3:27
+          StorageDead(_5);                 // scope 1 at $DIR/lower_array_len.rs:+4:1: +4:2
+          StorageDead(_2);                 // scope 0 at $DIR/lower_array_len.rs:+4:1: +4:2
+          StorageDead(_7);                 // scope 0 at $DIR/lower_array_len.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/lower_array_len.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/lower_array_len.array_len_reborrow.NormalizeArrayLen.diff b/tests/mir-opt/lower_array_len.array_len_reborrow.NormalizeArrayLen.diff
new file mode 100644
index 000000000..8bdd2ede6
--- /dev/null
+++ b/tests/mir-opt/lower_array_len.array_len_reborrow.NormalizeArrayLen.diff
@@ -0,0 +1,44 @@
+- // MIR for `array_len_reborrow` before NormalizeArrayLen
++ // MIR for `array_len_reborrow` after NormalizeArrayLen
+  
+  fn array_len_reborrow(_1: [u8; N]) -> usize {
+      debug arr => _1;                     // in scope 0 at $DIR/lower_array_len.rs:+0:43: +0:50
+      let mut _0: usize;                   // return place in scope 0 at $DIR/lower_array_len.rs:+0:64: +0:69
+      let _2: &mut [u8];                   // in scope 0 at $DIR/lower_array_len.rs:+1:9: +1:12
+      let mut _3: &mut [u8; N];            // in scope 0 at $DIR/lower_array_len.rs:+1:25: +1:33
+      let mut _4: &mut [u8; N];            // in scope 0 at $DIR/lower_array_len.rs:+1:25: +1:33
+      let mut _6: &[u8];                   // in scope 0 at $DIR/lower_array_len.rs:+3:5: +3:14
+      scope 1 {
+          debug arr => _2;                 // in scope 1 at $DIR/lower_array_len.rs:+1:9: +1:12
+          let _5: &[u8];                   // in scope 1 at $DIR/lower_array_len.rs:+2:9: +2:12
+          scope 2 {
+              debug arr => _5;             // in scope 2 at $DIR/lower_array_len.rs:+2:9: +2:12
+          }
+      }
+  
+      bb0: {
+          StorageLive(_2);                 // scope 0 at $DIR/lower_array_len.rs:+1:9: +1:12
+          StorageLive(_3);                 // scope 0 at $DIR/lower_array_len.rs:+1:25: +1:33
+          StorageLive(_4);                 // scope 0 at $DIR/lower_array_len.rs:+1:25: +1:33
+          _4 = &mut _1;                    // scope 0 at $DIR/lower_array_len.rs:+1:25: +1:33
+          _3 = &mut (*_4);                 // scope 0 at $DIR/lower_array_len.rs:+1:25: +1:33
+          _2 = move _3 as &mut [u8] (Pointer(Unsize)); // scope 0 at $DIR/lower_array_len.rs:+1:25: +1:33
+          StorageDead(_3);                 // scope 0 at $DIR/lower_array_len.rs:+1:32: +1:33
+          StorageDead(_4);                 // scope 0 at $DIR/lower_array_len.rs:+1:33: +1:34
+          StorageLive(_5);                 // scope 1 at $DIR/lower_array_len.rs:+2:9: +2:12
+          _5 = &(*_2);                     // scope 1 at $DIR/lower_array_len.rs:+2:15: +2:20
+          StorageLive(_6);                 // scope 2 at $DIR/lower_array_len.rs:+3:5: +3:14
+          _6 = &(*_5);                     // scope 2 at $DIR/lower_array_len.rs:+3:5: +3:14
+-         _0 = Len((*_6));                 // scope 2 at $DIR/lower_array_len.rs:+3:5: +3:14
++         _0 = const N;                    // scope 2 at $DIR/lower_array_len.rs:+3:5: +3:14
+          goto -> bb1;                     // scope 2 at $DIR/lower_array_len.rs:+3:5: +3:14
+      }
+  
+      bb1: {
+          StorageDead(_6);                 // scope 2 at $DIR/lower_array_len.rs:+3:13: +3:14
+          StorageDead(_5);                 // scope 1 at $DIR/lower_array_len.rs:+4:1: +4:2
+          StorageDead(_2);                 // scope 0 at $DIR/lower_array_len.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/lower_array_len.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/lower_array_len.rs b/tests/mir-opt/lower_array_len.rs
index ea0224b21..972d46cb8 100644
--- a/tests/mir-opt/lower_array_len.rs
+++ b/tests/mir-opt/lower_array_len.rs
@@ -31,10 +31,26 @@ pub fn array_len_by_value<const N: usize>(arr: [u8; N]) -> usize {
     arr.len()
 }
 
+// EMIT_MIR lower_array_len.array_len_reborrow.NormalizeArrayLen.diff
+pub fn array_len_reborrow<const N: usize>(mut arr: [u8; N]) -> usize {
+    let arr: &mut [_] = &mut arr;
+    let arr = &*arr;
+    arr.len()
+}
+
+// EMIT_MIR lower_array_len.array_len_raw.NormalizeArrayLen.diff
+pub fn array_len_raw<const N: usize>(arr: [u8; N]) -> usize {
+    let arr: &[_] = &arr;
+    let arr = std::ptr::addr_of!(*arr);
+    unsafe { &*arr }.len()
+}
+
 fn main() {
     let _ = array_bound(3, &[0, 1, 2, 3]);
     let mut tmp = [0, 1, 2, 3, 4];
     let _ = array_bound_mut(3, &mut [0, 1, 2, 3]);
     let _ = array_len(&[0]);
     let _ = array_len_by_value([0, 2]);
+    let _ = array_len_reborrow([0, 2]);
+    let _ = array_len_raw([0, 2]);
 }
diff --git a/tests/mir-opt/lower_array_len_e2e.array_bound.PreCodegen.after.mir b/tests/mir-opt/lower_array_len_e2e.array_bound.PreCodegen.after.mir
deleted file mode 100644
index 701c2ad70..000000000
--- a/tests/mir-opt/lower_array_len_e2e.array_bound.PreCodegen.after.mir
+++ /dev/null
@@ -1,45 +0,0 @@
-// MIR for `array_bound` after PreCodegen
-
-fn array_bound(_1: usize, _2: &[u8; N]) -> u8 {
-    debug index => _1;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+0:36: +0:41
-    debug slice => _2;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+0:50: +0:55
-    let mut _0: u8;                      // return place in scope 0 at $DIR/lower_array_len_e2e.rs:+0:70: +0:72
-    let mut _3: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-    let mut _4: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-    let mut _5: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-    let mut _6: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-    let mut _7: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-
-    bb0: {
-        StorageLive(_3);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-        StorageLive(_4);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-        _4 = _1;                         // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-        StorageLive(_5);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-        _5 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-        _3 = Lt(move _4, move _5);       // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-        StorageDead(_5);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:26: +1:27
-        StorageDead(_4);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:26: +1:27
-        switchInt(move _3) -> [0: bb3, otherwise: bb1]; // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-    }
-
-    bb1: {
-        _6 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-        _7 = Lt(_1, _6);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-        assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _1) -> bb2; // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-    }
-
-    bb2: {
-        _0 = (*_2)[_1];                  // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-        goto -> bb4;                     // scope 0 at $DIR/lower_array_len_e2e.rs:+1:5: +5:6
-    }
-
-    bb3: {
-        _0 = const 42_u8;                // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:11
-        goto -> bb4;                     // scope 0 at $DIR/lower_array_len_e2e.rs:+1:5: +5:6
-    }
-
-    bb4: {
-        StorageDead(_3);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+5:5: +5:6
-        return;                          // scope 0 at $DIR/lower_array_len_e2e.rs:+6:2: +6:2
-    }
-}
diff --git a/tests/mir-opt/lower_array_len_e2e.array_bound_mut.PreCodegen.after.mir b/tests/mir-opt/lower_array_len_e2e.array_bound_mut.PreCodegen.after.mir
deleted file mode 100644
index 0440cfce2..000000000
--- a/tests/mir-opt/lower_array_len_e2e.array_bound_mut.PreCodegen.after.mir
+++ /dev/null
@@ -1,58 +0,0 @@
-// MIR for `array_bound_mut` after PreCodegen
-
-fn array_bound_mut(_1: usize, _2: &mut [u8; N]) -> u8 {
-    debug index => _1;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+0:40: +0:45
-    debug slice => _2;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+0:54: +0:59
-    let mut _0: u8;                      // return place in scope 0 at $DIR/lower_array_len_e2e.rs:+0:78: +0:80
-    let mut _3: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-    let mut _4: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-    let mut _5: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-    let mut _6: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-    let mut _7: bool;                    // in scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-    let _8: usize;                       // in scope 0 at $DIR/lower_array_len_e2e.rs:+4:15: +4:16
-    let mut _9: usize;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
-    let mut _10: bool;                   // in scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
-
-    bb0: {
-        StorageLive(_3);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-        StorageLive(_4);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-        _4 = _1;                         // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:13
-        StorageLive(_5);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-        _5 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+1:16: +1:27
-        _3 = Lt(move _4, move _5);       // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-        StorageDead(_5);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:26: +1:27
-        StorageDead(_4);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+1:26: +1:27
-        switchInt(move _3) -> [0: bb3, otherwise: bb1]; // scope 0 at $DIR/lower_array_len_e2e.rs:+1:8: +1:27
-    }
-
-    bb1: {
-        _6 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-        _7 = Lt(_1, _6);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-        assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _1) -> bb2; // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-    }
-
-    bb2: {
-        _0 = (*_2)[_1];                  // scope 0 at $DIR/lower_array_len_e2e.rs:+2:9: +2:21
-        goto -> bb5;                     // scope 0 at $DIR/lower_array_len_e2e.rs:+1:5: +7:6
-    }
-
-    bb3: {
-        StorageLive(_8);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+4:15: +4:16
-        _8 = const 0_usize;              // scope 0 at $DIR/lower_array_len_e2e.rs:+4:15: +4:16
-        _9 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
-        _10 = Lt(const 0_usize, _9);     // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
-        assert(move _10, "index out of bounds: the length is {} but the index is {}", move _9, const 0_usize) -> bb4; // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:17
-    }
-
-    bb4: {
-        (*_2)[_8] = const 42_u8;         // scope 0 at $DIR/lower_array_len_e2e.rs:+4:9: +4:22
-        StorageDead(_8);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+4:22: +4:23
-        _0 = const 42_u8;                // scope 0 at $DIR/lower_array_len_e2e.rs:+6:9: +6:11
-        goto -> bb5;                     // scope 0 at $DIR/lower_array_len_e2e.rs:+1:5: +7:6
-    }
-
-    bb5: {
-        StorageDead(_3);                 // scope 0 at $DIR/lower_array_len_e2e.rs:+7:5: +7:6
-        return;                          // scope 0 at $DIR/lower_array_len_e2e.rs:+8:2: +8:2
-    }
-}
diff --git a/tests/mir-opt/lower_array_len_e2e.array_len.PreCodegen.after.mir b/tests/mir-opt/lower_array_len_e2e.array_len.PreCodegen.after.mir
deleted file mode 100644
index 4b19f6795..000000000
--- a/tests/mir-opt/lower_array_len_e2e.array_len.PreCodegen.after.mir
+++ /dev/null
@@ -1,11 +0,0 @@
-// MIR for `array_len` after PreCodegen
-
-fn array_len(_1: &[u8; N]) -> usize {
-    debug arr => _1;                     // in scope 0 at $DIR/lower_array_len_e2e.rs:+0:34: +0:37
-    let mut _0: usize;                   // return place in scope 0 at $DIR/lower_array_len_e2e.rs:+0:52: +0:57
-
-    bb0: {
-        _0 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+1:5: +1:14
-        return;                          // scope 0 at $DIR/lower_array_len_e2e.rs:+2:2: +2:2
-    }
-}
diff --git a/tests/mir-opt/lower_array_len_e2e.array_len_by_value.PreCodegen.after.mir b/tests/mir-opt/lower_array_len_e2e.array_len_by_value.PreCodegen.after.mir
deleted file mode 100644
index 4dc0ba9a2..000000000
--- a/tests/mir-opt/lower_array_len_e2e.array_len_by_value.PreCodegen.after.mir
+++ /dev/null
@@ -1,11 +0,0 @@
-// MIR for `array_len_by_value` after PreCodegen
-
-fn array_len_by_value(_1: [u8; N]) -> usize {
-    debug arr => _1;                     // in scope 0 at $DIR/lower_array_len_e2e.rs:+0:43: +0:46
-    let mut _0: usize;                   // return place in scope 0 at $DIR/lower_array_len_e2e.rs:+0:60: +0:65
-
-    bb0: {
-        _0 = const N;                    // scope 0 at $DIR/lower_array_len_e2e.rs:+1:5: +1:14
-        return;                          // scope 0 at $DIR/lower_array_len_e2e.rs:+2:2: +2:2
-    }
-}
diff --git a/tests/mir-opt/lower_array_len_e2e.rs b/tests/mir-opt/lower_array_len_e2e.rs
deleted file mode 100644
index d8e4e521e..000000000
--- a/tests/mir-opt/lower_array_len_e2e.rs
+++ /dev/null
@@ -1,39 +0,0 @@
-// compile-flags: -Z mir-opt-level=4 -Zunsound-mir-opts
-
-// EMIT_MIR lower_array_len_e2e.array_bound.PreCodegen.after.mir
-pub fn array_bound<const N: usize>(index: usize, slice: &[u8; N]) -> u8 {
-    if index < slice.len() {
-        slice[index]
-    } else {
-        42
-    }
-}
-
-// EMIT_MIR lower_array_len_e2e.array_bound_mut.PreCodegen.after.mir
-pub fn array_bound_mut<const N: usize>(index: usize, slice: &mut [u8; N]) -> u8 {
-    if index < slice.len() {
-        slice[index]
-    } else {
-        slice[0] = 42;
-
-        42
-    }
-}
-
-// EMIT_MIR lower_array_len_e2e.array_len.PreCodegen.after.mir
-pub fn array_len<const N: usize>(arr: &[u8; N]) -> usize {
-    arr.len()
-}
-
-// EMIT_MIR lower_array_len_e2e.array_len_by_value.PreCodegen.after.mir
-pub fn array_len_by_value<const N: usize>(arr: [u8; N]) -> usize {
-    arr.len()
-}
-
-fn main() {
-    let _ = array_bound(3, &[0, 1, 2, 3]);
-    let mut tmp = [0, 1, 2, 3, 4];
-    let _ = array_bound_mut(3, &mut [0, 1, 2, 3]);
-    let _ = array_len(&[0]);
-    let _ = array_len_by_value([0, 2]);
-}
diff --git a/tests/mir-opt/lower_intrinsics.f_copy_nonoverlapping.LowerIntrinsics.diff b/tests/mir-opt/lower_intrinsics.f_copy_nonoverlapping.LowerIntrinsics.diff
index ec15fd1ef..5c972a00e 100644
--- a/tests/mir-opt/lower_intrinsics.f_copy_nonoverlapping.LowerIntrinsics.diff
+++ b/tests/mir-opt/lower_intrinsics.f_copy_nonoverlapping.LowerIntrinsics.diff
@@ -25,9 +25,9 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/lower_intrinsics.rs:+1:9: +1:12
-          Deinit(_1);                      // scope 0 at $DIR/lower_intrinsics.rs:+1:15: +1:17
+          _1 = ();                         // scope 0 at $DIR/lower_intrinsics.rs:+1:15: +1:17
           StorageLive(_2);                 // scope 1 at $DIR/lower_intrinsics.rs:+2:9: +2:16
-          Deinit(_2);                      // scope 1 at $DIR/lower_intrinsics.rs:+2:19: +2:21
+          _2 = ();                         // scope 1 at $DIR/lower_intrinsics.rs:+2:19: +2:21
           StorageLive(_3);                 // scope 3 at $DIR/lower_intrinsics.rs:+4:9: +4:95
           StorageLive(_4);                 // scope 3 at $DIR/lower_intrinsics.rs:+4:29: +4:59
           StorageLive(_5);                 // scope 3 at $DIR/lower_intrinsics.rs:+4:29: +4:45
diff --git a/tests/mir-opt/lower_intrinsics.rs b/tests/mir-opt/lower_intrinsics.rs
index 66dae0e46..7147be43c 100644
--- a/tests/mir-opt/lower_intrinsics.rs
+++ b/tests/mir-opt/lower_intrinsics.rs
@@ -72,3 +72,10 @@ pub fn assume() {
         std::intrinsics::assume(true);
     }
 }
+
+// EMIT_MIR lower_intrinsics.with_overflow.LowerIntrinsics.diff
+pub fn with_overflow(a: i32, b: i32) {
+    let _x = core::intrinsics::add_with_overflow(a, b);
+    let _y = core::intrinsics::sub_with_overflow(a, b);
+    let _z = core::intrinsics::mul_with_overflow(a, b);
+}
diff --git a/tests/mir-opt/lower_intrinsics.with_overflow.LowerIntrinsics.diff b/tests/mir-opt/lower_intrinsics.with_overflow.LowerIntrinsics.diff
new file mode 100644
index 000000000..9870a70de
--- /dev/null
+++ b/tests/mir-opt/lower_intrinsics.with_overflow.LowerIntrinsics.diff
@@ -0,0 +1,83 @@
+- // MIR for `with_overflow` before LowerIntrinsics
++ // MIR for `with_overflow` after LowerIntrinsics
+  
+  fn with_overflow(_1: i32, _2: i32) -> () {
+      debug a => _1;                       // in scope 0 at $DIR/lower_intrinsics.rs:+0:22: +0:23
+      debug b => _2;                       // in scope 0 at $DIR/lower_intrinsics.rs:+0:30: +0:31
+      let mut _0: ();                      // return place in scope 0 at $DIR/lower_intrinsics.rs:+0:38: +0:38
+      let _3: (i32, bool);                 // in scope 0 at $DIR/lower_intrinsics.rs:+1:9: +1:11
+      let mut _4: i32;                     // in scope 0 at $DIR/lower_intrinsics.rs:+1:50: +1:51
+      let mut _5: i32;                     // in scope 0 at $DIR/lower_intrinsics.rs:+1:53: +1:54
+      let mut _7: i32;                     // in scope 0 at $DIR/lower_intrinsics.rs:+2:50: +2:51
+      let mut _8: i32;                     // in scope 0 at $DIR/lower_intrinsics.rs:+2:53: +2:54
+      let mut _10: i32;                    // in scope 0 at $DIR/lower_intrinsics.rs:+3:50: +3:51
+      let mut _11: i32;                    // in scope 0 at $DIR/lower_intrinsics.rs:+3:53: +3:54
+      scope 1 {
+          debug _x => _3;                  // in scope 1 at $DIR/lower_intrinsics.rs:+1:9: +1:11
+          let _6: (i32, bool);             // in scope 1 at $DIR/lower_intrinsics.rs:+2:9: +2:11
+          scope 2 {
+              debug _y => _6;              // in scope 2 at $DIR/lower_intrinsics.rs:+2:9: +2:11
+              let _9: (i32, bool);         // in scope 2 at $DIR/lower_intrinsics.rs:+3:9: +3:11
+              scope 3 {
+                  debug _z => _9;          // in scope 3 at $DIR/lower_intrinsics.rs:+3:9: +3:11
+              }
+          }
+      }
+  
+      bb0: {
+          StorageLive(_3);                 // scope 0 at $DIR/lower_intrinsics.rs:+1:9: +1:11
+          StorageLive(_4);                 // scope 0 at $DIR/lower_intrinsics.rs:+1:50: +1:51
+          _4 = _1;                         // scope 0 at $DIR/lower_intrinsics.rs:+1:50: +1:51
+          StorageLive(_5);                 // scope 0 at $DIR/lower_intrinsics.rs:+1:53: +1:54
+          _5 = _2;                         // scope 0 at $DIR/lower_intrinsics.rs:+1:53: +1:54
+-         _3 = add_with_overflow::<i32>(move _4, move _5) -> bb1; // scope 0 at $DIR/lower_intrinsics.rs:+1:14: +1:55
+-                                          // mir::Constant
+-                                          // + span: $DIR/lower_intrinsics.rs:78:14: 78:49
+-                                          // + literal: Const { ty: extern "rust-intrinsic" fn(i32, i32) -> (i32, bool) {add_with_overflow::<i32>}, val: Value(<ZST>) }
++         _3 = CheckedAdd(move _4, move _5); // scope 0 at $DIR/lower_intrinsics.rs:+1:14: +1:55
++         goto -> bb1;                     // scope 0 at $DIR/lower_intrinsics.rs:+1:14: +1:55
+      }
+  
+      bb1: {
+          StorageDead(_5);                 // scope 0 at $DIR/lower_intrinsics.rs:+1:54: +1:55
+          StorageDead(_4);                 // scope 0 at $DIR/lower_intrinsics.rs:+1:54: +1:55
+          StorageLive(_6);                 // scope 1 at $DIR/lower_intrinsics.rs:+2:9: +2:11
+          StorageLive(_7);                 // scope 1 at $DIR/lower_intrinsics.rs:+2:50: +2:51
+          _7 = _1;                         // scope 1 at $DIR/lower_intrinsics.rs:+2:50: +2:51
+          StorageLive(_8);                 // scope 1 at $DIR/lower_intrinsics.rs:+2:53: +2:54
+          _8 = _2;                         // scope 1 at $DIR/lower_intrinsics.rs:+2:53: +2:54
+-         _6 = sub_with_overflow::<i32>(move _7, move _8) -> bb2; // scope 1 at $DIR/lower_intrinsics.rs:+2:14: +2:55
+-                                          // mir::Constant
+-                                          // + span: $DIR/lower_intrinsics.rs:79:14: 79:49
+-                                          // + literal: Const { ty: extern "rust-intrinsic" fn(i32, i32) -> (i32, bool) {sub_with_overflow::<i32>}, val: Value(<ZST>) }
++         _6 = CheckedSub(move _7, move _8); // scope 1 at $DIR/lower_intrinsics.rs:+2:14: +2:55
++         goto -> bb2;                     // scope 1 at $DIR/lower_intrinsics.rs:+2:14: +2:55
+      }
+  
+      bb2: {
+          StorageDead(_8);                 // scope 1 at $DIR/lower_intrinsics.rs:+2:54: +2:55
+          StorageDead(_7);                 // scope 1 at $DIR/lower_intrinsics.rs:+2:54: +2:55
+          StorageLive(_9);                 // scope 2 at $DIR/lower_intrinsics.rs:+3:9: +3:11
+          StorageLive(_10);                // scope 2 at $DIR/lower_intrinsics.rs:+3:50: +3:51
+          _10 = _1;                        // scope 2 at $DIR/lower_intrinsics.rs:+3:50: +3:51
+          StorageLive(_11);                // scope 2 at $DIR/lower_intrinsics.rs:+3:53: +3:54
+          _11 = _2;                        // scope 2 at $DIR/lower_intrinsics.rs:+3:53: +3:54
+-         _9 = mul_with_overflow::<i32>(move _10, move _11) -> bb3; // scope 2 at $DIR/lower_intrinsics.rs:+3:14: +3:55
+-                                          // mir::Constant
+-                                          // + span: $DIR/lower_intrinsics.rs:80:14: 80:49
+-                                          // + literal: Const { ty: extern "rust-intrinsic" fn(i32, i32) -> (i32, bool) {mul_with_overflow::<i32>}, val: Value(<ZST>) }
++         _9 = CheckedMul(move _10, move _11); // scope 2 at $DIR/lower_intrinsics.rs:+3:14: +3:55
++         goto -> bb3;                     // scope 2 at $DIR/lower_intrinsics.rs:+3:14: +3:55
+      }
+  
+      bb3: {
+          StorageDead(_11);                // scope 2 at $DIR/lower_intrinsics.rs:+3:54: +3:55
+          StorageDead(_10);                // scope 2 at $DIR/lower_intrinsics.rs:+3:54: +3:55
+          _0 = const ();                   // scope 0 at $DIR/lower_intrinsics.rs:+0:38: +4:2
+          StorageDead(_9);                 // scope 2 at $DIR/lower_intrinsics.rs:+4:1: +4:2
+          StorageDead(_6);                 // scope 1 at $DIR/lower_intrinsics.rs:+4:1: +4:2
+          StorageDead(_3);                 // scope 0 at $DIR/lower_intrinsics.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/lower_intrinsics.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/matches_reduce_branches.bar.MatchBranchSimplification.diff b/tests/mir-opt/matches_reduce_branches.bar.MatchBranchSimplification.diff
index be91b0bfe..92f8d4e14 100644
--- a/tests/mir-opt/matches_reduce_branches.bar.MatchBranchSimplification.diff
+++ b/tests/mir-opt/matches_reduce_branches.bar.MatchBranchSimplification.diff
@@ -41,7 +41,7 @@
 -         _3 = const false;                // scope 4 at $DIR/matches_reduce_branches.rs:+16:13: +16:22
 -         _4 = const false;                // scope 4 at $DIR/matches_reduce_branches.rs:+17:13: +17:22
 -         _5 = const true;                 // scope 4 at $DIR/matches_reduce_branches.rs:+18:13: +18:21
--         Deinit(_6);                      // scope 4 at $DIR/matches_reduce_branches.rs:+19:13: +19:15
+-         _6 = ();                         // scope 4 at $DIR/matches_reduce_branches.rs:+19:13: +19:15
 -         goto -> bb3;                     // scope 4 at $DIR/matches_reduce_branches.rs:+19:13: +19:15
 -     }
 - 
@@ -54,7 +54,7 @@
 +         _3 = Eq(_11, const 7_i32);       // scope 4 at $DIR/matches_reduce_branches.rs:+9:13: +9:21
           _4 = const false;                // scope 4 at $DIR/matches_reduce_branches.rs:+10:13: +10:22
           _5 = const true;                 // scope 4 at $DIR/matches_reduce_branches.rs:+11:13: +11:21
-          Deinit(_6);                      // scope 4 at $DIR/matches_reduce_branches.rs:+12:13: +12:15
+          _6 = ();                         // scope 4 at $DIR/matches_reduce_branches.rs:+12:13: +12:15
 -         goto -> bb3;                     // scope 4 at $DIR/matches_reduce_branches.rs:+12:13: +12:15
 -     }
 - 
@@ -69,11 +69,7 @@
           _9 = _4;                         // scope 4 at $DIR/matches_reduce_branches.rs:+23:12: +23:13
           StorageLive(_10);                // scope 4 at $DIR/matches_reduce_branches.rs:+23:15: +23:16
           _10 = _5;                        // scope 4 at $DIR/matches_reduce_branches.rs:+23:15: +23:16
-          Deinit(_0);                      // scope 4 at $DIR/matches_reduce_branches.rs:+23:5: +23:17
-          (_0.0: bool) = move _7;          // scope 4 at $DIR/matches_reduce_branches.rs:+23:5: +23:17
-          (_0.1: bool) = move _8;          // scope 4 at $DIR/matches_reduce_branches.rs:+23:5: +23:17
-          (_0.2: bool) = move _9;          // scope 4 at $DIR/matches_reduce_branches.rs:+23:5: +23:17
-          (_0.3: bool) = move _10;         // scope 4 at $DIR/matches_reduce_branches.rs:+23:5: +23:17
+          _0 = (move _7, move _8, move _9, move _10); // scope 4 at $DIR/matches_reduce_branches.rs:+23:5: +23:17
           StorageDead(_10);                // scope 4 at $DIR/matches_reduce_branches.rs:+23:16: +23:17
           StorageDead(_9);                 // scope 4 at $DIR/matches_reduce_branches.rs:+23:16: +23:17
           StorageDead(_8);                 // scope 4 at $DIR/matches_reduce_branches.rs:+23:16: +23:17
diff --git a/tests/mir-opt/matches_reduce_branches.foo.MatchBranchSimplification.diff b/tests/mir-opt/matches_reduce_branches.foo.MatchBranchSimplification.diff
index aa8092ece..0580f7334 100644
--- a/tests/mir-opt/matches_reduce_branches.foo.MatchBranchSimplification.diff
+++ b/tests/mir-opt/matches_reduce_branches.foo.MatchBranchSimplification.diff
@@ -34,7 +34,7 @@
 -     }
 - 
 -     bb4: {
-          Deinit(_0);                      // scope 0 at $DIR/matches_reduce_branches.rs:+2:9: +2:11
+          _0 = ();                         // scope 0 at $DIR/matches_reduce_branches.rs:+2:9: +2:11
 -         goto -> bb6;                     // scope 0 at $DIR/matches_reduce_branches.rs:+1:5: +3:6
 +         goto -> bb3;                     // scope 0 at $DIR/matches_reduce_branches.rs:+1:5: +3:6
       }
diff --git a/tests/mir-opt/matches_reduce_branches.match_nested_if.MatchBranchSimplification.diff b/tests/mir-opt/matches_reduce_branches.match_nested_if.MatchBranchSimplification.diff
index 193104dd3..20e8ef2f7 100644
--- a/tests/mir-opt/matches_reduce_branches.match_nested_if.MatchBranchSimplification.diff
+++ b/tests/mir-opt/matches_reduce_branches.match_nested_if.MatchBranchSimplification.diff
@@ -20,7 +20,7 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/matches_reduce_branches.rs:+1:9: +1:12
           StorageLive(_2);                 // scope 0 at $DIR/matches_reduce_branches.rs:+1:21: +1:23
-          Deinit(_2);                      // scope 0 at $DIR/matches_reduce_branches.rs:+1:21: +1:23
+          _2 = ();                         // scope 0 at $DIR/matches_reduce_branches.rs:+1:21: +1:23
           StorageLive(_3);                 // scope 0 at $DIR/matches_reduce_branches.rs:+2:15: +6:10
           StorageLive(_4);                 // scope 0 at $DIR/matches_reduce_branches.rs:+2:18: +2:76
           StorageLive(_5);                 // scope 0 at $DIR/matches_reduce_branches.rs:+2:21: +2:52
diff --git a/tests/mir-opt/packed_struct_drop_aligned.main.SimplifyCfg-elaborate-drops.after.mir b/tests/mir-opt/packed_struct_drop_aligned.main.SimplifyCfg-elaborate-drops.after.mir
index e52253486..210f178a0 100644
--- a/tests/mir-opt/packed_struct_drop_aligned.main.SimplifyCfg-elaborate-drops.after.mir
+++ b/tests/mir-opt/packed_struct_drop_aligned.main.SimplifyCfg-elaborate-drops.after.mir
@@ -16,20 +16,15 @@ fn main() -> () {
         StorageLive(_1);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:9: +1:14
         StorageLive(_2);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:24: +1:42
         StorageLive(_3);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:32: +1:41
-        Deinit(_3);                      // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:32: +1:41
-        (_3.0: usize) = const 0_usize;   // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:32: +1:41
-        Deinit(_2);                      // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:24: +1:42
-        (_2.0: Droppy) = move _3;        // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:24: +1:42
+        _3 = Droppy(const 0_usize);      // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:32: +1:41
+        _2 = Aligned(move _3);           // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:24: +1:42
         StorageDead(_3);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:41: +1:42
-        Deinit(_1);                      // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:17: +1:43
-        (_1.0: Aligned) = move _2;       // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:17: +1:43
+        _1 = Packed(move _2);            // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:17: +1:43
         StorageDead(_2);                 // scope 0 at $DIR/packed_struct_drop_aligned.rs:+1:42: +1:43
         StorageLive(_4);                 // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:11: +2:29
         StorageLive(_5);                 // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:19: +2:28
-        Deinit(_5);                      // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:19: +2:28
-        (_5.0: usize) = const 0_usize;   // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:19: +2:28
-        Deinit(_4);                      // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:11: +2:29
-        (_4.0: Droppy) = move _5;        // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:11: +2:29
+        _5 = Droppy(const 0_usize);      // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:19: +2:28
+        _4 = Aligned(move _5);           // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:11: +2:29
         StorageDead(_5);                 // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:28: +2:29
         StorageLive(_6);                 // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:5: +2:8
         _6 = move (_1.0: Aligned);       // scope 1 at $DIR/packed_struct_drop_aligned.rs:+2:5: +2:8
diff --git a/tests/mir-opt/remove_storage_markers.main.RemoveStorageMarkers.diff b/tests/mir-opt/remove_storage_markers.main.RemoveStorageMarkers.diff
index ed1d0b87f..a8dd91efc 100644
--- a/tests/mir-opt/remove_storage_markers.main.RemoveStorageMarkers.diff
+++ b/tests/mir-opt/remove_storage_markers.main.RemoveStorageMarkers.diff
@@ -31,9 +31,7 @@
           _1 = const 0_i32;                // scope 0 at $DIR/remove_storage_markers.rs:+1:19: +1:20
 -         StorageLive(_2);                 // scope 1 at $DIR/remove_storage_markers.rs:+2:14: +2:19
 -         StorageLive(_3);                 // scope 1 at $DIR/remove_storage_markers.rs:+2:14: +2:19
-          Deinit(_3);                      // scope 1 at $DIR/remove_storage_markers.rs:+2:14: +2:19
-          (_3.0: i32) = const 0_i32;       // scope 1 at $DIR/remove_storage_markers.rs:+2:14: +2:19
-          (_3.1: i32) = const 10_i32;      // scope 1 at $DIR/remove_storage_markers.rs:+2:14: +2:19
+          _3 = std::ops::Range::<i32> { start: const 0_i32, end: const 10_i32 }; // scope 1 at $DIR/remove_storage_markers.rs:+2:14: +2:19
           _2 = <std::ops::Range<i32> as IntoIterator>::into_iter(move _3) -> bb1; // scope 1 at $DIR/remove_storage_markers.rs:+2:14: +2:19
                                            // mir::Constant
                                            // + span: $DIR/remove_storage_markers.rs:10:14: 10:19
diff --git a/tests/mir-opt/remove_zsts.get_union.PreCodegen.after.mir b/tests/mir-opt/remove_zsts.get_union.PreCodegen.after.mir
index 12e914e25..af34bc5ed 100644
--- a/tests/mir-opt/remove_zsts.get_union.PreCodegen.after.mir
+++ b/tests/mir-opt/remove_zsts.get_union.PreCodegen.after.mir
@@ -2,9 +2,12 @@
 
 fn get_union() -> Foo {
     let mut _0: Foo;                     // return place in scope 0 at $DIR/remove_zsts.rs:+0:19: +0:22
+    let mut _1: ();                      // in scope 0 at $DIR/remove_zsts.rs:+1:14: +1:16
 
     bb0: {
-        Deinit(_0);                      // scope 0 at $DIR/remove_zsts.rs:+1:5: +1:18
+        StorageLive(_1);                 // scope 0 at $DIR/remove_zsts.rs:+1:14: +1:16
+        _0 = Foo { x: move _1 };         // scope 0 at $DIR/remove_zsts.rs:+1:5: +1:18
+        StorageDead(_1);                 // scope 0 at $DIR/remove_zsts.rs:+1:17: +1:18
         return;                          // scope 0 at $DIR/remove_zsts.rs:+2:2: +2:2
     }
 }
diff --git a/tests/mir-opt/remove_zsts.get_union.RemoveZsts.diff b/tests/mir-opt/remove_zsts.get_union.RemoveZsts.diff
index 169b7b105..0af29b2ba 100644
--- a/tests/mir-opt/remove_zsts.get_union.RemoveZsts.diff
+++ b/tests/mir-opt/remove_zsts.get_union.RemoveZsts.diff
@@ -7,11 +7,9 @@
   
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/remove_zsts.rs:+1:14: +1:16
--         Deinit(_1);                      // scope 0 at $DIR/remove_zsts.rs:+1:14: +1:16
+-         _1 = ();                         // scope 0 at $DIR/remove_zsts.rs:+1:14: +1:16
 +         nop;                             // scope 0 at $DIR/remove_zsts.rs:+1:14: +1:16
-          Deinit(_0);                      // scope 0 at $DIR/remove_zsts.rs:+1:5: +1:18
--         (_0.0: ()) = move _1;            // scope 0 at $DIR/remove_zsts.rs:+1:5: +1:18
-+         nop;                             // scope 0 at $DIR/remove_zsts.rs:+1:5: +1:18
+          _0 = Foo { x: move _1 };         // scope 0 at $DIR/remove_zsts.rs:+1:5: +1:18
           StorageDead(_1);                 // scope 0 at $DIR/remove_zsts.rs:+1:17: +1:18
           return;                          // scope 0 at $DIR/remove_zsts.rs:+2:2: +2:2
       }
diff --git a/tests/mir-opt/retag.array_casts.SimplifyCfg-elaborate-drops.after.mir b/tests/mir-opt/retag.array_casts.SimplifyCfg-elaborate-drops.after.mir
index 19b726e74..3b479710b 100644
--- a/tests/mir-opt/retag.array_casts.SimplifyCfg-elaborate-drops.after.mir
+++ b/tests/mir-opt/retag.array_casts.SimplifyCfg-elaborate-drops.after.mir
@@ -122,9 +122,7 @@ fn array_casts() -> () {
                                          // + literal: Const { ty: &usize, val: Unevaluated(array_casts, [], Some(promoted[0])) }
         Retag(_35);                      // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         _18 = &(*_35);                   // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        Deinit(_13);                     // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        (_13.0: &usize) = move _14;      // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        (_13.1: &usize) = move _18;      // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        _13 = (move _14, move _18);      // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         Retag(_13);                      // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageDead(_18);                // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageDead(_14);                // scope 5 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -150,8 +148,7 @@ fn array_casts() -> () {
 
     bb3: {
         StorageLive(_27);                // scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        Deinit(_27);                     // scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        discriminant(_27) = 0;           // scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        _27 = core::panicking::AssertKind::Eq; // scope 7 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_28);                // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_29);                // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         _29 = move _27;                  // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
@@ -164,8 +161,7 @@ fn array_casts() -> () {
         _33 = &(*_21);                   // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         _32 = &(*_33);                   // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         StorageLive(_34);                // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        Deinit(_34);                     // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
-        discriminant(_34) = 0;           // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
+        _34 = Option::<Arguments<'_>>::None; // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         Retag(_34);                      // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
         _28 = core::panicking::assert_failed::<usize, usize>(move _29, move _30, move _32, move _34); // scope 8 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
                                          // mir::Constant
diff --git a/tests/mir-opt/retag.main.SimplifyCfg-elaborate-drops.after.mir b/tests/mir-opt/retag.main.SimplifyCfg-elaborate-drops.after.mir
index b853e4505..d7b6d64b6 100644
--- a/tests/mir-opt/retag.main.SimplifyCfg-elaborate-drops.after.mir
+++ b/tests/mir-opt/retag.main.SimplifyCfg-elaborate-drops.after.mir
@@ -62,8 +62,7 @@ fn main() -> () {
         StorageLive(_3);                 // scope 1 at $DIR/retag.rs:+3:13: +3:14
         StorageLive(_4);                 // scope 1 at $DIR/retag.rs:+3:17: +3:36
         StorageLive(_5);                 // scope 1 at $DIR/retag.rs:+3:17: +3:24
-        Deinit(_5);                      // scope 1 at $DIR/retag.rs:+3:17: +3:24
-        (_5.0: i32) = const 0_i32;       // scope 1 at $DIR/retag.rs:+3:17: +3:24
+        _5 = Test(const 0_i32);          // scope 1 at $DIR/retag.rs:+3:17: +3:24
         _4 = &_5;                        // scope 1 at $DIR/retag.rs:+3:17: +3:36
         StorageLive(_6);                 // scope 1 at $DIR/retag.rs:+3:29: +3:35
         StorageLive(_7);                 // scope 1 at $DIR/retag.rs:+3:29: +3:35
@@ -107,7 +106,14 @@ fn main() -> () {
         StorageDead(_2);                 // scope 1 at $DIR/retag.rs:+8:5: +8:6
         StorageLive(_13);                // scope 1 at $DIR/retag.rs:+11:9: +11:10
         StorageLive(_14);                // scope 1 at $DIR/retag.rs:+11:31: +14:6
-        Deinit(_14);                     // scope 1 at $DIR/retag.rs:+11:31: +14:6
+        _14 = [closure@main::{closure#0}]; // scope 1 at $DIR/retag.rs:+11:31: +14:6
+                                         // closure
+                                         // + def_id: DefId(0:14 ~ retag[4622]::main::{closure#0})
+                                         // + substs: [
+                                         //     i8,
+                                         //     for<'a> extern "rust-call" fn((&'a i32,)) -> &'a i32,
+                                         //     (),
+                                         // ]
         Retag(_14);                      // scope 1 at $DIR/retag.rs:+11:31: +14:6
         _13 = move _14 as for<'a> fn(&'a i32) -> &'a i32 (Pointer(ClosureFnPointer(Normal))); // scope 1 at $DIR/retag.rs:+11:31: +14:6
         StorageDead(_14);                // scope 1 at $DIR/retag.rs:+11:47: +11:48
@@ -129,8 +135,7 @@ fn main() -> () {
         StorageLive(_19);                // scope 7 at $DIR/retag.rs:+18:5: +18:24
         StorageLive(_20);                // scope 7 at $DIR/retag.rs:+18:5: +18:24
         StorageLive(_21);                // scope 7 at $DIR/retag.rs:+18:5: +18:12
-        Deinit(_21);                     // scope 7 at $DIR/retag.rs:+18:5: +18:12
-        (_21.0: i32) = const 0_i32;      // scope 7 at $DIR/retag.rs:+18:5: +18:12
+        _21 = Test(const 0_i32);         // scope 7 at $DIR/retag.rs:+18:5: +18:12
         _20 = &_21;                      // scope 7 at $DIR/retag.rs:+18:5: +18:24
         StorageLive(_22);                // scope 7 at $DIR/retag.rs:+18:21: +18:23
         StorageLive(_23);                // scope 7 at $DIR/retag.rs:+18:21: +18:23
diff --git a/tests/mir-opt/separate_const_switch.identity.SeparateConstSwitch.diff b/tests/mir-opt/separate_const_switch.identity.SeparateConstSwitch.diff
index e57544e09..cfcd43093 100644
--- a/tests/mir-opt/separate_const_switch.identity.SeparateConstSwitch.diff
+++ b/tests/mir-opt/separate_const_switch.identity.SeparateConstSwitch.diff
@@ -12,18 +12,18 @@
       let mut _7: !;                       // in scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
       let mut _8: std::result::Result<std::convert::Infallible, i32>; // in scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
       let _9: i32;                         // in scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
+      let mut _16: i32;                    // in scope 0 at $SRC_DIR/core/src/result.rs:LL:COL
       scope 1 {
           debug residual => _6;            // in scope 1 at $DIR/separate_const_switch.rs:+1:9: +1:10
           scope 2 {
               scope 8 (inlined #[track_caller] <Result<i32, i32> as FromResidual<Result<Infallible, i32>>>::from_residual) { // at $DIR/separate_const_switch.rs:25:8: 25:10
                   debug residual => _8;    // in scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
-                  let _16: i32;            // in scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
-                  let mut _17: i32;        // in scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
-                  let mut _18: i32;        // in scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
+                  let _14: i32;            // in scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
+                  let mut _15: i32;        // in scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
                   scope 9 {
-                      debug e => _16;      // in scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
+                      debug e => _14;      // in scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
                       scope 10 (inlined <i32 as From<i32>>::from) { // at $SRC_DIR/core/src/result.rs:LL:COL
-                          debug t => _18;  // in scope 10 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
+                          debug t => _16;  // in scope 10 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
                       }
                   }
               }
@@ -38,15 +38,13 @@
           debug self => _4;                // in scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
           let mut _10: isize;              // in scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
           let _11: i32;                    // in scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
-          let mut _12: i32;                // in scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
-          let _13: i32;                    // in scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
-          let mut _14: std::result::Result<std::convert::Infallible, i32>; // in scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
-          let mut _15: i32;                // in scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
+          let _12: i32;                    // in scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
+          let mut _13: std::result::Result<std::convert::Infallible, i32>; // in scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
           scope 6 {
               debug v => _11;              // in scope 6 at $SRC_DIR/core/src/result.rs:LL:COL
           }
           scope 7 {
-              debug e => _13;              // in scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
+              debug e => _12;              // in scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
           }
       }
   
@@ -55,53 +53,50 @@
           StorageLive(_3);                 // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
           StorageLive(_4);                 // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:9
           _4 = _1;                         // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:9
+          StorageLive(_11);                // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
+          StorageLive(_12);                // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
           _10 = discriminant(_4);          // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
--         switchInt(move _10) -> [0: bb7, 1: bb5, otherwise: bb6]; // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
-+         switchInt(move _10) -> [0: bb6, 1: bb4, otherwise: bb5]; // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
+          switchInt(move _10) -> [0: bb7, 1: bb5, otherwise: bb6]; // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
       }
   
       bb1: {
--         StorageDead(_4);                 // scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
--         _5 = discriminant(_3);           // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
--         switchInt(move _5) -> [0: bb2, 1: bb4, otherwise: bb3]; // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
--     }
-- 
--     bb2: {
+          StorageDead(_12);                // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
+          StorageDead(_11);                // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
+          StorageDead(_4);                 // scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
+          _5 = discriminant(_3);           // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
+          switchInt(move _5) -> [0: bb2, 1: bb4, otherwise: bb3]; // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
+      }
+  
+      bb2: {
           StorageLive(_9);                 // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
           _9 = ((_3 as Continue).0: i32);  // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
           _2 = _9;                         // scope 4 at $DIR/separate_const_switch.rs:+1:8: +1:10
           StorageDead(_9);                 // scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
-          Deinit(_0);                      // scope 0 at $DIR/separate_const_switch.rs:+1:5: +1:11
-          ((_0 as Ok).0: i32) = move _2;   // scope 0 at $DIR/separate_const_switch.rs:+1:5: +1:11
-          discriminant(_0) = 0;            // scope 0 at $DIR/separate_const_switch.rs:+1:5: +1:11
+          _0 = Result::<i32, i32>::Ok(move _2); // scope 0 at $DIR/separate_const_switch.rs:+1:5: +1:11
           StorageDead(_2);                 // scope 0 at $DIR/separate_const_switch.rs:+1:10: +1:11
           StorageDead(_3);                 // scope 0 at $DIR/separate_const_switch.rs:+2:1: +2:2
           return;                          // scope 0 at $DIR/separate_const_switch.rs:+2:2: +2:2
       }
   
--     bb3: {
-+     bb2: {
+      bb3: {
           unreachable;                     // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
       }
   
--     bb4: {
-+     bb3: {
+      bb4: {
           StorageLive(_6);                 // scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
           _6 = ((_3 as Break).0: std::result::Result<std::convert::Infallible, i32>); // scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
           StorageLive(_8);                 // scope 2 at $DIR/separate_const_switch.rs:+1:9: +1:10
           _8 = _6;                         // scope 2 at $DIR/separate_const_switch.rs:+1:9: +1:10
-          StorageLive(_16);                // scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
-          _16 = move ((_8 as Err).0: i32); // scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageLive(_17);                // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageLive(_18);                // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
-          _18 = move _16;                  // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
-          _17 = move _18;                  // scope 10 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
-          StorageDead(_18);                // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
-          Deinit(_0);                      // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
-          ((_0 as Err).0: i32) = move _17; // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
-          discriminant(_0) = 1;            // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageDead(_17);                // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageDead(_16);                // scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
+          StorageLive(_14);                // scope 2 at $DIR/separate_const_switch.rs:+1:8: +1:10
+          _14 = move ((_8 as Err).0: i32); // scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
+          StorageLive(_15);                // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
+          StorageLive(_16);                // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
+          _16 = move _14;                  // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
+          _15 = move _16;                  // scope 10 at $SRC_DIR/core/src/convert/mod.rs:LL:COL
+          StorageDead(_16);                // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
+          _0 = Result::<i32, i32>::Err(move _15); // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
+          StorageDead(_15);                // scope 9 at $SRC_DIR/core/src/result.rs:LL:COL
+          StorageDead(_14);                // scope 2 at $DIR/separate_const_switch.rs:+1:8: +1:10
           StorageDead(_8);                 // scope 2 at $DIR/separate_const_switch.rs:+1:9: +1:10
           StorageDead(_6);                 // scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
           StorageDead(_2);                 // scope 0 at $DIR/separate_const_switch.rs:+1:10: +1:11
@@ -109,48 +104,23 @@
           return;                          // scope 0 at $DIR/separate_const_switch.rs:+2:2: +2:2
       }
   
--     bb5: {
-+     bb4: {
-          StorageLive(_13);                // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
-          _13 = move ((_4 as Err).0: i32); // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageLive(_14);                // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageLive(_15);                // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          _15 = move _13;                  // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          Deinit(_14);                     // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          ((_14 as Err).0: i32) = move _15; // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          discriminant(_14) = 1;           // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageDead(_15);                // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          Deinit(_3);                      // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          ((_3 as Break).0: std::result::Result<std::convert::Infallible, i32>) = move _14; // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          discriminant(_3) = 1;            // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageDead(_14);                // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageDead(_13);                // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
--         goto -> bb1;                     // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
-+         StorageDead(_4);                 // scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
-+         _5 = discriminant(_3);           // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
-+         switchInt(move _5) -> [0: bb1, 1: bb3, otherwise: bb2]; // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
+      bb5: {
+          _12 = move ((_4 as Err).0: i32); // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
+          StorageLive(_13);                // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
+          _13 = Result::<Infallible, i32>::Err(move _12); // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
+          _3 = ControlFlow::<Result<Infallible, i32>, i32>::Break(move _13); // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
+          StorageDead(_13);                // scope 7 at $SRC_DIR/core/src/result.rs:LL:COL
+          goto -> bb1;                     // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
       }
   
--     bb6: {
-+     bb5: {
+      bb6: {
           unreachable;                     // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
       }
   
--     bb7: {
-+     bb6: {
-          StorageLive(_11);                // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
+      bb7: {
           _11 = move ((_4 as Ok).0: i32);  // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageLive(_12);                // scope 6 at $SRC_DIR/core/src/result.rs:LL:COL
-          _12 = move _11;                  // scope 6 at $SRC_DIR/core/src/result.rs:LL:COL
-          Deinit(_3);                      // scope 6 at $SRC_DIR/core/src/result.rs:LL:COL
-          ((_3 as Continue).0: i32) = move _12; // scope 6 at $SRC_DIR/core/src/result.rs:LL:COL
-          discriminant(_3) = 0;            // scope 6 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageDead(_12);                // scope 6 at $SRC_DIR/core/src/result.rs:LL:COL
-          StorageDead(_11);                // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
--         goto -> bb1;                     // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
-+         StorageDead(_4);                 // scope 0 at $DIR/separate_const_switch.rs:+1:9: +1:10
-+         _5 = discriminant(_3);           // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
-+         switchInt(move _5) -> [0: bb1, 1: bb3, otherwise: bb2]; // scope 0 at $DIR/separate_const_switch.rs:+1:8: +1:10
+          _3 = ControlFlow::<Result<Infallible, i32>, i32>::Continue(move _11); // scope 6 at $SRC_DIR/core/src/result.rs:LL:COL
+          goto -> bb1;                     // scope 5 at $SRC_DIR/core/src/result.rs:LL:COL
       }
   }
   
diff --git a/tests/mir-opt/separate_const_switch.too_complex.SeparateConstSwitch.diff b/tests/mir-opt/separate_const_switch.too_complex.SeparateConstSwitch.diff
index 8cc0c6a18..3c7e9dc61 100644
--- a/tests/mir-opt/separate_const_switch.too_complex.SeparateConstSwitch.diff
+++ b/tests/mir-opt/separate_const_switch.too_complex.SeparateConstSwitch.diff
@@ -38,14 +38,10 @@
           _6 = ((_1 as Err).0: usize);     // scope 0 at $DIR/separate_const_switch.rs:+8:17: +8:18
           StorageLive(_7);                 // scope 2 at $DIR/separate_const_switch.rs:+8:42: +8:43
           _7 = _6;                         // scope 2 at $DIR/separate_const_switch.rs:+8:42: +8:43
-          Deinit(_2);                      // scope 2 at $DIR/separate_const_switch.rs:+8:23: +8:44
-          ((_2 as Break).0: usize) = move _7; // scope 2 at $DIR/separate_const_switch.rs:+8:23: +8:44
-          discriminant(_2) = 1;            // scope 2 at $DIR/separate_const_switch.rs:+8:23: +8:44
+          _2 = ControlFlow::<usize, i32>::Break(move _7); // scope 2 at $DIR/separate_const_switch.rs:+8:23: +8:44
           StorageDead(_7);                 // scope 2 at $DIR/separate_const_switch.rs:+8:43: +8:44
           StorageDead(_6);                 // scope 0 at $DIR/separate_const_switch.rs:+8:43: +8:44
--         goto -> bb4;                     // scope 0 at $DIR/separate_const_switch.rs:+8:43: +8:44
-+         _8 = discriminant(_2);           // scope 0 at $DIR/separate_const_switch.rs:+5:11: +10:6
-+         switchInt(move _8) -> [0: bb6, 1: bb4, otherwise: bb5]; // scope 0 at $DIR/separate_const_switch.rs:+5:5: +10:6
+          goto -> bb4;                     // scope 0 at $DIR/separate_const_switch.rs:+8:43: +8:44
       }
   
       bb2: {
@@ -57,53 +53,41 @@
           _4 = ((_1 as Ok).0: i32);        // scope 0 at $DIR/separate_const_switch.rs:+7:16: +7:17
           StorageLive(_5);                 // scope 1 at $DIR/separate_const_switch.rs:+7:44: +7:45
           _5 = _4;                         // scope 1 at $DIR/separate_const_switch.rs:+7:44: +7:45
-          Deinit(_2);                      // scope 1 at $DIR/separate_const_switch.rs:+7:22: +7:46
-          ((_2 as Continue).0: i32) = move _5; // scope 1 at $DIR/separate_const_switch.rs:+7:22: +7:46
-          discriminant(_2) = 0;            // scope 1 at $DIR/separate_const_switch.rs:+7:22: +7:46
+          _2 = ControlFlow::<usize, i32>::Continue(move _5); // scope 1 at $DIR/separate_const_switch.rs:+7:22: +7:46
           StorageDead(_5);                 // scope 1 at $DIR/separate_const_switch.rs:+7:45: +7:46
           StorageDead(_4);                 // scope 0 at $DIR/separate_const_switch.rs:+7:45: +7:46
--         goto -> bb4;                     // scope 0 at $DIR/separate_const_switch.rs:+7:45: +7:46
--     }
-- 
--     bb4: {
+          goto -> bb4;                     // scope 0 at $DIR/separate_const_switch.rs:+7:45: +7:46
+      }
+  
+      bb4: {
           _8 = discriminant(_2);           // scope 0 at $DIR/separate_const_switch.rs:+5:11: +10:6
--         switchInt(move _8) -> [0: bb7, 1: bb5, otherwise: bb6]; // scope 0 at $DIR/separate_const_switch.rs:+5:5: +10:6
-+         switchInt(move _8) -> [0: bb6, 1: bb4, otherwise: bb5]; // scope 0 at $DIR/separate_const_switch.rs:+5:5: +10:6
+          switchInt(move _8) -> [0: bb7, 1: bb5, otherwise: bb6]; // scope 0 at $DIR/separate_const_switch.rs:+5:5: +10:6
       }
   
--     bb5: {
-+     bb4: {
+      bb5: {
           StorageLive(_11);                // scope 0 at $DIR/separate_const_switch.rs:+12:28: +12:29
           _11 = ((_2 as Break).0: usize);  // scope 0 at $DIR/separate_const_switch.rs:+12:28: +12:29
-          Deinit(_0);                      // scope 4 at $DIR/separate_const_switch.rs:+12:34: +12:38
-          discriminant(_0) = 0;            // scope 4 at $DIR/separate_const_switch.rs:+12:34: +12:38
+          _0 = Option::<i32>::None;        // scope 4 at $DIR/separate_const_switch.rs:+12:34: +12:38
           StorageDead(_11);                // scope 0 at $DIR/separate_const_switch.rs:+12:37: +12:38
--         goto -> bb8;                     // scope 0 at $DIR/separate_const_switch.rs:+12:37: +12:38
-+         goto -> bb7;                     // scope 0 at $DIR/separate_const_switch.rs:+12:37: +12:38
+          goto -> bb8;                     // scope 0 at $DIR/separate_const_switch.rs:+12:37: +12:38
       }
   
--     bb6: {
-+     bb5: {
+      bb6: {
           unreachable;                     // scope 0 at $DIR/separate_const_switch.rs:+5:11: +10:6
       }
   
--     bb7: {
-+     bb6: {
+      bb7: {
           StorageLive(_9);                 // scope 0 at $DIR/separate_const_switch.rs:+11:31: +11:32
           _9 = ((_2 as Continue).0: i32);  // scope 0 at $DIR/separate_const_switch.rs:+11:31: +11:32
           StorageLive(_10);                // scope 3 at $DIR/separate_const_switch.rs:+11:42: +11:43
           _10 = _9;                        // scope 3 at $DIR/separate_const_switch.rs:+11:42: +11:43
-          Deinit(_0);                      // scope 3 at $DIR/separate_const_switch.rs:+11:37: +11:44
-          ((_0 as Some).0: i32) = move _10; // scope 3 at $DIR/separate_const_switch.rs:+11:37: +11:44
-          discriminant(_0) = 1;            // scope 3 at $DIR/separate_const_switch.rs:+11:37: +11:44
+          _0 = Option::<i32>::Some(move _10); // scope 3 at $DIR/separate_const_switch.rs:+11:37: +11:44
           StorageDead(_10);                // scope 3 at $DIR/separate_const_switch.rs:+11:43: +11:44
           StorageDead(_9);                 // scope 0 at $DIR/separate_const_switch.rs:+11:43: +11:44
--         goto -> bb8;                     // scope 0 at $DIR/separate_const_switch.rs:+11:43: +11:44
-+         goto -> bb7;                     // scope 0 at $DIR/separate_const_switch.rs:+11:43: +11:44
+          goto -> bb8;                     // scope 0 at $DIR/separate_const_switch.rs:+11:43: +11:44
       }
   
--     bb8: {
-+     bb7: {
+      bb8: {
           StorageDead(_2);                 // scope 0 at $DIR/separate_const_switch.rs:+14:1: +14:2
           return;                          // scope 0 at $DIR/separate_const_switch.rs:+14:2: +14:2
       }
diff --git a/tests/mir-opt/simple_option_map_e2e.ezmap.PreCodegen.after.mir b/tests/mir-opt/simple_option_map_e2e.ezmap.PreCodegen.after.mir
index 916f99049..66ba4df76 100644
--- a/tests/mir-opt/simple_option_map_e2e.ezmap.PreCodegen.after.mir
+++ b/tests/mir-opt/simple_option_map_e2e.ezmap.PreCodegen.after.mir
@@ -8,12 +8,12 @@ fn ezmap(_1: Option<i32>) -> Option<i32> {
         debug slf => _1;                 // in scope 1 at $DIR/simple_option_map_e2e.rs:2:17: 2:20
         debug f => _2;                   // in scope 1 at $DIR/simple_option_map_e2e.rs:2:33: 2:34
         let mut _3: isize;               // in scope 1 at $DIR/simple_option_map_e2e.rs:7:9: 7:16
-        let mut _4: i32;                 // in scope 1 at $DIR/simple_option_map_e2e.rs:7:25: 7:29
+        let _4: i32;                     // in scope 1 at $DIR/simple_option_map_e2e.rs:7:14: 7:15
         let mut _5: i32;                 // in scope 1 at $DIR/simple_option_map_e2e.rs:7:25: 7:29
         scope 2 {
-            debug x => _5;               // in scope 2 at $DIR/simple_option_map_e2e.rs:7:14: 7:15
+            debug x => _4;               // in scope 2 at $DIR/simple_option_map_e2e.rs:7:14: 7:15
             scope 3 (inlined ezmap::{closure#0}) { // at $DIR/simple_option_map_e2e.rs:7:25: 7:29
-                debug n => _5;           // in scope 3 at $DIR/simple_option_map_e2e.rs:+1:13: +1:14
+                debug n => _4;           // in scope 3 at $DIR/simple_option_map_e2e.rs:+1:13: +1:14
             }
         }
     }
@@ -25,8 +25,7 @@ fn ezmap(_1: Option<i32>) -> Option<i32> {
     }
 
     bb1: {
-        Deinit(_0);                      // scope 1 at $DIR/simple_option_map_e2e.rs:8:17: 8:21
-        discriminant(_0) = 0;            // scope 1 at $DIR/simple_option_map_e2e.rs:8:17: 8:21
+        _0 = Option::<i32>::None;        // scope 1 at $DIR/simple_option_map_e2e.rs:8:17: 8:21
         goto -> bb4;                     // scope 1 at $DIR/simple_option_map_e2e.rs:8:17: 8:21
     }
 
@@ -35,13 +34,11 @@ fn ezmap(_1: Option<i32>) -> Option<i32> {
     }
 
     bb3: {
-        _5 = move ((_1 as Some).0: i32); // scope 1 at $DIR/simple_option_map_e2e.rs:7:14: 7:15
-        StorageLive(_4);                 // scope 2 at $DIR/simple_option_map_e2e.rs:7:25: 7:29
-        _4 = Add(move _5, const 1_i32);  // scope 3 at $DIR/simple_option_map_e2e.rs:+1:16: +1:21
-        Deinit(_0);                      // scope 2 at $DIR/simple_option_map_e2e.rs:7:20: 7:30
-        ((_0 as Some).0: i32) = move _4; // scope 2 at $DIR/simple_option_map_e2e.rs:7:20: 7:30
-        discriminant(_0) = 1;            // scope 2 at $DIR/simple_option_map_e2e.rs:7:20: 7:30
-        StorageDead(_4);                 // scope 2 at $DIR/simple_option_map_e2e.rs:7:29: 7:30
+        _4 = ((_1 as Some).0: i32);      // scope 1 at $DIR/simple_option_map_e2e.rs:7:14: 7:15
+        StorageLive(_5);                 // scope 2 at $DIR/simple_option_map_e2e.rs:7:25: 7:29
+        _5 = Add(_4, const 1_i32);       // scope 3 at $DIR/simple_option_map_e2e.rs:+1:16: +1:21
+        _0 = Option::<i32>::Some(move _5); // scope 2 at $DIR/simple_option_map_e2e.rs:7:20: 7:30
+        StorageDead(_5);                 // scope 2 at $DIR/simple_option_map_e2e.rs:7:29: 7:30
         goto -> bb4;                     // scope 1 at $DIR/simple_option_map_e2e.rs:10:1: 10:2
     }
 
diff --git a/tests/mir-opt/simplify_locals.d1.SimplifyLocals-before-const-prop.diff b/tests/mir-opt/simplify_locals.d1.SimplifyLocals-before-const-prop.diff
index 981738030..946595e32 100644
--- a/tests/mir-opt/simplify_locals.d1.SimplifyLocals-before-const-prop.diff
+++ b/tests/mir-opt/simplify_locals.d1.SimplifyLocals-before-const-prop.diff
@@ -9,8 +9,7 @@
   
       bb0: {
 -         StorageLive(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:13: +2:17
--         Deinit(_1);                      // scope 0 at $DIR/simplify_locals.rs:+2:13: +2:17
--         discriminant(_1) = 0;            // scope 0 at $DIR/simplify_locals.rs:+2:13: +2:17
+-         _1 = E::A;                       // scope 0 at $DIR/simplify_locals.rs:+2:13: +2:17
 -         StorageDead(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:17: +2:18
           _0 = const ();                   // scope 0 at $DIR/simplify_locals.rs:+0:9: +3:2
           return;                          // scope 0 at $DIR/simplify_locals.rs:+3:2: +3:2
diff --git a/tests/mir-opt/simplify_locals.d2.SimplifyLocals-before-const-prop.diff b/tests/mir-opt/simplify_locals.d2.SimplifyLocals-before-const-prop.diff
index b152dc8cc..6a5dc56e2 100644
--- a/tests/mir-opt/simplify_locals.d2.SimplifyLocals-before-const-prop.diff
+++ b/tests/mir-opt/simplify_locals.d2.SimplifyLocals-before-const-prop.diff
@@ -9,15 +9,11 @@
   
       bb0: {
 -         StorageLive(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:22: +2:26
--         Deinit(_1);                      // scope 0 at $DIR/simplify_locals.rs:+2:22: +2:26
--         discriminant(_1) = 1;            // scope 0 at $DIR/simplify_locals.rs:+2:22: +2:26
+-         _1 = E::B;                       // scope 0 at $DIR/simplify_locals.rs:+2:22: +2:26
 -         StorageLive(_2);                 // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:17
 -         StorageLive(_3);                 // scope 0 at $DIR/simplify_locals.rs:+2:11: +2:15
--         Deinit(_3);                      // scope 0 at $DIR/simplify_locals.rs:+2:11: +2:15
--         discriminant(_3) = 0;            // scope 0 at $DIR/simplify_locals.rs:+2:11: +2:15
--         Deinit(_2);                      // scope 0 at $DIR/simplify_locals.rs:+2:6: +2:16
--         (_2.0: i32) = const 10_i32;      // scope 0 at $DIR/simplify_locals.rs:+2:6: +2:16
--         (_2.1: E) = move _3;             // scope 0 at $DIR/simplify_locals.rs:+2:6: +2:16
+-         _3 = E::A;                       // scope 0 at $DIR/simplify_locals.rs:+2:11: +2:15
+-         _2 = (const 10_i32, move _3);    // scope 0 at $DIR/simplify_locals.rs:+2:6: +2:16
 -         StorageDead(_3);                 // scope 0 at $DIR/simplify_locals.rs:+2:15: +2:16
 -         (_2.1: E) = move _1;             // scope 0 at $DIR/simplify_locals.rs:+2:5: +2:26
 -         StorageDead(_1);                 // scope 0 at $DIR/simplify_locals.rs:+2:25: +2:26
diff --git a/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.diff b/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.diff
index f888c622d..f908e8dd0 100644
--- a/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.diff
+++ b/tests/mir-opt/simplify_locals_fixedpoint.foo.SimplifyLocals-final.diff
@@ -18,14 +18,10 @@
       bb0: {
           StorageLive(_1);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:30: +1:69
           StorageLive(_2);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:31: +1:49
-          Deinit(_2);                      // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:31: +1:49
-          discriminant(_2) = 0;            // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:31: +1:49
+          _2 = Option::<u8>::None;         // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:31: +1:49
           StorageLive(_3);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:51: +1:68
-          Deinit(_3);                      // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:51: +1:68
-          discriminant(_3) = 0;            // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:51: +1:68
-          Deinit(_1);                      // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:30: +1:69
-          (_1.0: std::option::Option<u8>) = move _2; // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:30: +1:69
-          (_1.1: std::option::Option<T>) = move _3; // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:30: +1:69
+          _3 = Option::<T>::None;          // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:51: +1:68
+          _1 = (move _2, move _3);         // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:30: +1:69
           StorageDead(_3);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:68: +1:69
           StorageDead(_2);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:68: +1:69
           _5 = discriminant((_1.0: std::option::Option<u8>)); // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:12: +1:27
@@ -38,15 +34,10 @@
       }
   
       bb2: {
-          StorageLive(_6);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:18: +1:19
           _6 = (((_1.0: std::option::Option<u8>) as Some).0: u8); // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+1:18: +1:19
 -         StorageLive(_7);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:20
--         StorageLive(_8);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:13
--         _8 = _6;                         // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:13
--         _7 = Gt(move _8, const 42_u8);   // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:20
--         StorageDead(_8);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:19: +2:20
+-         _7 = Gt(_6, const 42_u8);        // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+2:12: +2:20
 -         StorageDead(_7);                 // scope 1 at $DIR/simplify_locals_fixedpoint.rs:+4:9: +4:10
-          StorageDead(_6);                 // scope 0 at $DIR/simplify_locals_fixedpoint.rs:+5:5: +5:6
           goto -> bb3;                     // scope 0 at $DIR/simplify_locals_fixedpoint.rs:+1:5: +5:6
       }
   
diff --git a/tests/mir-opt/simplify_locals_removes_unused_consts.main.SimplifyLocals-before-const-prop.diff b/tests/mir-opt/simplify_locals_removes_unused_consts.main.SimplifyLocals-before-const-prop.diff
index efb2b0961..0f8866f9c 100644
--- a/tests/mir-opt/simplify_locals_removes_unused_consts.main.SimplifyLocals-before-const-prop.diff
+++ b/tests/mir-opt/simplify_locals_removes_unused_consts.main.SimplifyLocals-before-const-prop.diff
@@ -28,36 +28,30 @@
       bb0: {
 -         StorageLive(_1);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:20: +1:28
 -         StorageLive(_2);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:21: +1:23
--         Deinit(_2);                      // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:21: +1:23
+-         _2 = ();                         // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:21: +1:23
 -         StorageLive(_3);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:25: +1:27
--         Deinit(_3);                      // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:25: +1:27
--         Deinit(_1);                      // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:20: +1:28
--         (_1.0: ()) = move _2;            // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:20: +1:28
--         (_1.1: ()) = move _3;            // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:20: +1:28
+-         _3 = ();                         // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:25: +1:27
+-         _1 = (move _2, move _3);         // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:20: +1:28
 -         StorageDead(_3);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:27: +1:28
 -         StorageDead(_2);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:27: +1:28
 -         StorageDead(_1);                 // scope 0 at $DIR/simplify_locals_removes_unused_consts.rs:+1:28: +1:29
 -         StorageLive(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:5: +2:22
 -         StorageLive(_5);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
 -         StorageLive(_6);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
--         Deinit(_6);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
+-         _6 = ();                         // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
 -         StorageLive(_7);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
--         Deinit(_7);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
--         Deinit(_5);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
--         (_5.0: ()) = move _6;            // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
--         (_5.1: ()) = move _7;            // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
+-         _7 = ();                         // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
+-         _5 = (move _6, move _7);         // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
 -         StorageDead(_7);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:20: +2:21
 -         StorageDead(_6);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:20: +2:21
 -         _4 = use_zst(move _5) -> bb1;    // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:5: +2:22
 +         StorageLive(_1);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:5: +2:22
 +         StorageLive(_2);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
 +         StorageLive(_3);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
-+         Deinit(_3);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
++         _3 = ();                         // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:14: +2:16
 +         StorageLive(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
-+         Deinit(_4);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
-+         Deinit(_2);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
-+         (_2.0: ()) = move _3;            // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
-+         (_2.1: ()) = move _4;            // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
++         _4 = ();                         // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:18: +2:20
++         _2 = (move _3, move _4);         // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:13: +2:21
 +         StorageDead(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:20: +2:21
 +         StorageDead(_3);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:20: +2:21
 +         _1 = use_zst(move _2) -> bb1;    // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+2:5: +2:22
@@ -73,8 +67,7 @@
 -         StorageLive(_9);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:34
 -         StorageLive(_10);                // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:30
 -         StorageLive(_11);                // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
--         Deinit(_11);                     // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
--         (_11.0: u8) = const 40_u8;       // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
+-         _11 = Temp { x: const 40_u8 };   // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
 -         _10 = (_11.0: u8);               // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:30
 -         _9 = Add(move _10, const 2_u8);  // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:34
 -         StorageDead(_10);                // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:33: +4:34
@@ -85,8 +78,7 @@
 +         StorageLive(_6);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:34
 +         StorageLive(_7);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:30
 +         StorageLive(_8);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
-+         Deinit(_8);                      // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
-+         (_8.0: u8) = const 40_u8;        // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
++         _8 = Temp { x: const 40_u8 };    // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:28
 +         _7 = (_8.0: u8);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:30
 +         _6 = Add(move _7, const 2_u8);   // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:12: +4:34
 +         StorageDead(_7);                 // scope 1 at $DIR/simplify_locals_removes_unused_consts.rs:+4:33: +4:34
diff --git a/tests/mir-opt/simplify_locals_removes_unused_discriminant_reads.map.SimplifyLocals-before-const-prop.diff b/tests/mir-opt/simplify_locals_removes_unused_discriminant_reads.map.SimplifyLocals-before-const-prop.diff
index 027c983e6..3f9af31d8 100644
--- a/tests/mir-opt/simplify_locals_removes_unused_discriminant_reads.map.SimplifyLocals-before-const-prop.diff
+++ b/tests/mir-opt/simplify_locals_removes_unused_discriminant_reads.map.SimplifyLocals-before-const-prop.diff
@@ -26,9 +26,7 @@
           _3 = move ((_1 as Some).0: std::boxed::Box<()>); // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:14: +3:15
           StorageLive(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:25: +3:26
           _4 = move _3;                    // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:25: +3:26
-          Deinit(_0);                      // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:20: +3:27
-          ((_0 as Some).0: std::boxed::Box<()>) = move _4; // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:20: +3:27
-          discriminant(_0) = 1;            // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:20: +3:27
+          _0 = Option::<Box<()>>::Some(move _4); // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:20: +3:27
           StorageDead(_4);                 // scope 1 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:26: +3:27
           StorageDead(_3);                 // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:26: +3:27
           goto -> bb4;                     // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+3:26: +3:27
@@ -39,8 +37,7 @@
       }
   
       bb3: {
-          Deinit(_0);                      // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+2:17: +2:21
-          discriminant(_0) = 0;            // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+2:17: +2:21
+          _0 = Option::<Box<()>>::None;    // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+2:17: +2:21
           goto -> bb4;                     // scope 0 at $DIR/simplify_locals_removes_unused_discriminant_reads.rs:+2:17: +2:21
       }
   
diff --git a/tests/mir-opt/simplify_match.main.ConstProp.diff b/tests/mir-opt/simplify_match.main.ConstProp.diff
index 70bfbf1b3..b700adfb1 100644
--- a/tests/mir-opt/simplify_match.main.ConstProp.diff
+++ b/tests/mir-opt/simplify_match.main.ConstProp.diff
@@ -10,13 +10,8 @@
       }
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/simplify_match.rs:+1:11: +1:31
-          StorageLive(_2);                 // scope 0 at $DIR/simplify_match.rs:+1:17: +1:18
           _2 = const false;                // scope 0 at $DIR/simplify_match.rs:+1:21: +1:26
--         _1 = _2;                         // scope 1 at $DIR/simplify_match.rs:+1:28: +1:29
-+         _1 = const false;                // scope 1 at $DIR/simplify_match.rs:+1:28: +1:29
-          StorageDead(_2);                 // scope 0 at $DIR/simplify_match.rs:+1:30: +1:31
--         switchInt(_1) -> [0: bb1, otherwise: bb2]; // scope 0 at $DIR/simplify_match.rs:+1:5: +1:31
+-         switchInt(_2) -> [0: bb1, otherwise: bb2]; // scope 0 at $DIR/simplify_match.rs:+1:5: +1:31
 +         switchInt(const false) -> [0: bb1, otherwise: bb2]; // scope 0 at $DIR/simplify_match.rs:+1:5: +1:31
       }
   
@@ -32,7 +27,6 @@
       }
   
       bb3: {
-          StorageDead(_1);                 // scope 0 at $DIR/simplify_match.rs:+5:1: +5:2
           return;                          // scope 0 at $DIR/simplify_match.rs:+5:2: +5:2
       }
   }
diff --git a/tests/mir-opt/slice_filter.rs b/tests/mir-opt/slice_filter.rs
new file mode 100644
index 000000000..97c18af31
--- /dev/null
+++ b/tests/mir-opt/slice_filter.rs
@@ -0,0 +1,18 @@
+fn main() {
+    let input = vec![];
+    let _variant_a_result = variant_a(&input);
+    let _variant_b_result = variant_b(&input);
+}
+
+pub fn variant_a(input: &[(usize, usize, usize, usize)]) -> usize {
+    input.iter().filter(|(a, b, c, d)| a <= c && d <= b || c <= a && b <= d).count()
+}
+
+pub fn variant_b(input: &[(usize, usize, usize, usize)]) -> usize {
+    input.iter().filter(|&&(a, b, c, d)| a <= c && d <= b || c <= a && b <= d).count()
+}
+
+// EMIT_MIR slice_filter.variant_a-{closure#0}.CopyProp.diff
+// EMIT_MIR slice_filter.variant_a-{closure#0}.DestinationPropagation.diff
+// EMIT_MIR slice_filter.variant_b-{closure#0}.CopyProp.diff
+// EMIT_MIR slice_filter.variant_b-{closure#0}.DestinationPropagation.diff
diff --git a/tests/mir-opt/slice_filter.variant_a-{closure#0}.CopyProp.diff b/tests/mir-opt/slice_filter.variant_a-{closure#0}.CopyProp.diff
new file mode 100644
index 000000000..3bb0358ff
--- /dev/null
+++ b/tests/mir-opt/slice_filter.variant_a-{closure#0}.CopyProp.diff
@@ -0,0 +1,279 @@
+- // MIR for `variant_a::{closure#0}` before CopyProp
++ // MIR for `variant_a::{closure#0}` after CopyProp
+  
+  fn variant_a::{closure#0}(_1: &mut [closure@$DIR/slice_filter.rs:8:25: 8:39], _2: &&(usize, usize, usize, usize)) -> bool {
+      let mut _0: bool;                    // return place in scope 0 at $DIR/slice_filter.rs:+0:40: +0:40
+      let _3: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+      let _4: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+      let _5: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+      let _6: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+      let mut _7: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:56
+      let mut _8: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:46
+      let mut _9: &&usize;                 // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:41
+      let mut _10: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:45: +0:46
+      let _11: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:45: +0:46
+      let mut _12: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:50: +0:56
+      let mut _13: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:50: +0:51
+      let mut _14: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:55: +0:56
+      let _15: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:55: +0:56
+      let mut _16: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:76
+      let mut _17: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:66
+      let mut _18: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:61
+      let mut _19: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:65: +0:66
+      let _20: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:65: +0:66
+      let mut _21: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:70: +0:76
+      let mut _22: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:70: +0:71
+      let mut _23: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+      let _24: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+      let mut _25: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _26: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _27: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _28: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _31: &usize;                 // in scope 0 at $SRC_DIR/core/src/cmp.rs:LL:COL
+      let mut _32: &usize;                 // in scope 0 at $SRC_DIR/core/src/cmp.rs:LL:COL
+      let mut _37: &usize;                 // in scope 0 at $SRC_DIR/core/src/cmp.rs:LL:COL
+      let mut _38: &usize;                 // in scope 0 at $SRC_DIR/core/src/cmp.rs:LL:COL
+      let mut _43: &usize;                 // in scope 0 at $SRC_DIR/core/src/cmp.rs:LL:COL
+      let mut _44: &usize;                 // in scope 0 at $SRC_DIR/core/src/cmp.rs:LL:COL
+      let mut _49: &usize;                 // in scope 0 at $SRC_DIR/core/src/cmp.rs:LL:COL
+      let mut _50: &usize;                 // in scope 0 at $SRC_DIR/core/src/cmp.rs:LL:COL
+      scope 1 {
+          debug a => _3;                   // in scope 1 at $DIR/slice_filter.rs:+0:27: +0:28
+          debug b => _4;                   // in scope 1 at $DIR/slice_filter.rs:+0:30: +0:31
+          debug c => _5;                   // in scope 1 at $DIR/slice_filter.rs:+0:33: +0:34
+          debug d => _6;                   // in scope 1 at $DIR/slice_filter.rs:+0:36: +0:37
+          scope 2 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:40: 8:46
+              debug self => _9;            // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _10;          // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _29: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _30: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 3 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug self => _31;       // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug other => _32;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug self => _29;       // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug other => _30;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _33: usize;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _34: usize;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+          scope 4 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:60: 8:66
+              debug self => _18;           // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _19;          // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _35: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _36: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 5 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug self => _37;       // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug other => _38;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug self => _35;       // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug other => _36;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _39: usize;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _40: usize;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+          scope 6 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:50: 8:56
+              debug self => _13;           // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _14;          // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _41: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _42: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 7 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug self => _43;       // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug other => _44;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug self => _41;       // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug other => _42;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _45: usize;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _46: usize;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+          scope 8 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:70: 8:76
+              debug self => _22;           // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _23;          // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _47: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _48: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 9 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug self => _49;       // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-                 debug other => _50;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug self => _47;       // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
++                 debug other => _48;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _51: usize;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _52: usize;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+      }
+  
+      bb0: {
+-         StorageLive(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+          _25 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+          _3 = &((*_25).0: usize);         // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+-         StorageLive(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+          _26 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+          _4 = &((*_26).1: usize);         // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+-         StorageLive(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+          _27 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+          _5 = &((*_27).2: usize);         // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+-         StorageLive(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+          _28 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+          _6 = &((*_28).3: usize);         // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+          StorageLive(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+          StorageLive(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:46
+          StorageLive(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:41
+          _9 = &_3;                        // scope 1 at $DIR/slice_filter.rs:+0:40: +0:41
+          StorageLive(_10);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          StorageLive(_11);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          _11 = _5;                        // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          _10 = &_11;                      // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          _29 = deref_copy (*_9);          // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _30 = deref_copy (*_10);         // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_31);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _31 = _29;                       // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_32);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _32 = _30;                       // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_33);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _33 = (*_31);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _33 = (*_29);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_34);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _34 = (*_32);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _34 = (*_30);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _8 = Le(move _33, move _34);     // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_34);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_33);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_32);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_31);                // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          StorageDead(_10);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          switchInt(move _8) -> [0: bb4, otherwise: bb5]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+      }
+  
+      bb1: {
+          _0 = const true;                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+      }
+  
+      bb2: {
+          StorageLive(_16);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          StorageLive(_17);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:66
+          StorageLive(_18);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:61
+          _18 = &_5;                       // scope 1 at $DIR/slice_filter.rs:+0:60: +0:61
+          StorageLive(_19);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          StorageLive(_20);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          _20 = _3;                        // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          _19 = &_20;                      // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          _35 = deref_copy (*_18);         // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _36 = deref_copy (*_19);         // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_37);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _37 = _35;                       // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_38);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _38 = _36;                       // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_39);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _39 = (*_37);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _39 = (*_35);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_40);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _40 = (*_38);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _40 = (*_36);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _17 = Le(move _39, move _40);    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_40);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_39);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_38);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_37);                // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_20);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          StorageDead(_19);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          StorageDead(_18);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          switchInt(move _17) -> [0: bb6, otherwise: bb7]; // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+      }
+  
+      bb3: {
+          StorageDead(_16);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+          return;                          // scope 0 at $DIR/slice_filter.rs:+0:76: +0:76
+      }
+  
+      bb4: {
+          _7 = const false;                // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+          StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          goto -> bb2;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+      }
+  
+      bb5: {
+          StorageLive(_12);                // scope 1 at $DIR/slice_filter.rs:+0:50: +0:56
+          StorageLive(_13);                // scope 1 at $DIR/slice_filter.rs:+0:50: +0:51
+          _13 = &_6;                       // scope 1 at $DIR/slice_filter.rs:+0:50: +0:51
+          StorageLive(_14);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageLive(_15);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _15 = _4;                        // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _14 = &_15;                      // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _41 = deref_copy (*_13);         // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _42 = deref_copy (*_14);         // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_43);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _43 = _41;                       // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_44);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _44 = _42;                       // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_45);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _45 = (*_43);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _45 = (*_41);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_46);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _46 = (*_44);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _46 = (*_42);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _12 = Le(move _45, move _46);    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_46);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_45);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_44);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_43);                // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_15);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_14);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_13);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _7 = move _12;                   // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+          StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          switchInt(move _7) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+      }
+  
+      bb6: {
+          _16 = const false;               // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+      }
+  
+      bb7: {
+          StorageLive(_21);                // scope 1 at $DIR/slice_filter.rs:+0:70: +0:76
+          StorageLive(_22);                // scope 1 at $DIR/slice_filter.rs:+0:70: +0:71
+          _22 = &_4;                       // scope 1 at $DIR/slice_filter.rs:+0:70: +0:71
+          StorageLive(_23);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageLive(_24);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _24 = _6;                        // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _23 = &_24;                      // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _47 = deref_copy (*_22);         // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _48 = deref_copy (*_23);         // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_49);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _49 = _47;                       // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageLive(_50);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _50 = _48;                       // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_51);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _51 = (*_49);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _51 = (*_47);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_52);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _52 = (*_50);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _52 = (*_48);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _21 = Le(move _51, move _52);    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_52);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_51);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_50);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         StorageDead(_49);                // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_24);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_23);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_22);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _16 = move _21;                  // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+      }
+  
+      bb8: {
+          StorageDead(_21);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_17);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _0 = move _16;                   // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+      }
+  }
+  
diff --git a/tests/mir-opt/slice_filter.variant_a-{closure#0}.DestinationPropagation.diff b/tests/mir-opt/slice_filter.variant_a-{closure#0}.DestinationPropagation.diff
new file mode 100644
index 000000000..294c3272f
--- /dev/null
+++ b/tests/mir-opt/slice_filter.variant_a-{closure#0}.DestinationPropagation.diff
@@ -0,0 +1,237 @@
+- // MIR for `variant_a::{closure#0}` before DestinationPropagation
++ // MIR for `variant_a::{closure#0}` after DestinationPropagation
+  
+  fn variant_a::{closure#0}(_1: &mut [closure@$DIR/slice_filter.rs:8:25: 8:39], _2: &&(usize, usize, usize, usize)) -> bool {
+      let mut _0: bool;                    // return place in scope 0 at $DIR/slice_filter.rs:+0:40: +0:40
+      let _3: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+      let _4: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+      let _5: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+      let _6: &usize;                      // in scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+      let mut _7: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:56
+      let mut _8: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:46
+      let mut _9: &&usize;                 // in scope 0 at $DIR/slice_filter.rs:+0:40: +0:41
+      let mut _10: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:45: +0:46
+      let _11: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:45: +0:46
+      let mut _12: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:50: +0:56
+      let mut _13: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:50: +0:51
+      let mut _14: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:55: +0:56
+      let _15: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:55: +0:56
+      let mut _16: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:76
+      let mut _17: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:66
+      let mut _18: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:60: +0:61
+      let mut _19: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:65: +0:66
+      let _20: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:65: +0:66
+      let mut _21: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:70: +0:76
+      let mut _22: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:70: +0:71
+      let mut _23: &&usize;                // in scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+      let _24: &usize;                     // in scope 0 at $DIR/slice_filter.rs:+0:75: +0:76
+      let mut _25: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _26: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _27: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      let mut _28: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:38
+      scope 1 {
+          debug a => _3;                   // in scope 1 at $DIR/slice_filter.rs:+0:27: +0:28
+          debug b => _4;                   // in scope 1 at $DIR/slice_filter.rs:+0:30: +0:31
+          debug c => _5;                   // in scope 1 at $DIR/slice_filter.rs:+0:33: +0:34
+          debug d => _6;                   // in scope 1 at $DIR/slice_filter.rs:+0:36: +0:37
+          scope 2 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:40: 8:46
+              debug self => _9;            // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _10;          // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _29: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _30: &usize;         // in scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 3 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug self => _29;       // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug other => _30;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _31: usize;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _32: usize;      // in scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+          scope 4 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:60: 8:66
+              debug self => _18;           // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _19;          // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _33: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _34: &usize;         // in scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 5 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug self => _33;       // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug other => _34;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _35: usize;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _36: usize;      // in scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+          scope 6 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:50: 8:56
+              debug self => _13;           // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _14;          // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _37: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _38: &usize;         // in scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 7 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug self => _37;       // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug other => _38;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _39: usize;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _40: usize;      // in scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+          scope 8 (inlined cmp::impls::<impl PartialOrd for &usize>::le) { // at $DIR/slice_filter.rs:8:70: 8:76
+              debug self => _22;           // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              debug other => _23;          // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _41: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              let mut _42: &usize;         // in scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              scope 9 (inlined cmp::impls::<impl PartialOrd for usize>::le) { // at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug self => _41;       // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  debug other => _42;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _43: usize;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+                  let mut _44: usize;      // in scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+              }
+          }
+      }
+  
+      bb0: {
+          _25 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+          _3 = &((*_25).0: usize);         // scope 0 at $DIR/slice_filter.rs:+0:27: +0:28
+          _26 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+          _4 = &((*_26).1: usize);         // scope 0 at $DIR/slice_filter.rs:+0:30: +0:31
+          _27 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+          _5 = &((*_27).2: usize);         // scope 0 at $DIR/slice_filter.rs:+0:33: +0:34
+          _28 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+          _6 = &((*_28).3: usize);         // scope 0 at $DIR/slice_filter.rs:+0:36: +0:37
+-         StorageLive(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+          StorageLive(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:46
+          StorageLive(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:41
+          _9 = &_3;                        // scope 1 at $DIR/slice_filter.rs:+0:40: +0:41
+          StorageLive(_10);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          StorageLive(_11);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          _11 = _5;                        // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          _10 = &_11;                      // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          _29 = deref_copy (*_9);          // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _30 = deref_copy (*_10);         // scope 2 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_31);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _31 = (*_29);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_32);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _32 = (*_30);                    // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _8 = Le(move _31, move _32);     // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_32);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_31);                // scope 3 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          StorageDead(_10);                // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:45: +0:46
+          switchInt(move _8) -> [0: bb4, otherwise: bb5]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+      }
+  
+      bb1: {
+          _0 = const true;                 // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+      }
+  
+      bb2: {
+-         StorageLive(_16);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          StorageLive(_17);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:66
+          StorageLive(_18);                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:61
+          _18 = &_5;                       // scope 1 at $DIR/slice_filter.rs:+0:60: +0:61
+          StorageLive(_19);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          StorageLive(_20);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          _20 = _3;                        // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          _19 = &_20;                      // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          _33 = deref_copy (*_18);         // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _34 = deref_copy (*_19);         // scope 4 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_35);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _35 = (*_33);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_36);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _36 = (*_34);                    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _17 = Le(move _35, move _36);    // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_36);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_35);                // scope 5 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_20);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          StorageDead(_19);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          StorageDead(_18);                // scope 1 at $DIR/slice_filter.rs:+0:65: +0:66
+          switchInt(move _17) -> [0: bb6, otherwise: bb7]; // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+      }
+  
+      bb3: {
+-         StorageDead(_16);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         StorageDead(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          return;                          // scope 0 at $DIR/slice_filter.rs:+0:76: +0:76
+      }
+  
+      bb4: {
+-         StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          goto -> bb2;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+      }
+  
+      bb5: {
+-         StorageLive(_12);                // scope 1 at $DIR/slice_filter.rs:+0:50: +0:56
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:50: +0:56
+          StorageLive(_13);                // scope 1 at $DIR/slice_filter.rs:+0:50: +0:51
+          _13 = &_6;                       // scope 1 at $DIR/slice_filter.rs:+0:50: +0:51
+          StorageLive(_14);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageLive(_15);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _15 = _4;                        // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _14 = &_15;                      // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          _37 = deref_copy (*_13);         // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _38 = deref_copy (*_14);         // scope 6 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_39);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _39 = (*_37);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_40);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _40 = (*_38);                    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _12 = Le(move _39, move _40);    // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_40);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_39);                // scope 7 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_15);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_14);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_13);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+-         _7 = move _12;                   // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
+-         StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:40: +0:56
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:55: +0:56
+-         switchInt(move _7) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
++         switchInt(move _12) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+      }
+  
+      bb6: {
+-         _16 = const false;               // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
++         _0 = const false;                // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+      }
+  
+      bb7: {
+-         StorageLive(_21);                // scope 1 at $DIR/slice_filter.rs:+0:70: +0:76
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:70: +0:76
+          StorageLive(_22);                // scope 1 at $DIR/slice_filter.rs:+0:70: +0:71
+          _22 = &_4;                       // scope 1 at $DIR/slice_filter.rs:+0:70: +0:71
+          StorageLive(_23);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageLive(_24);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _24 = _6;                        // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _23 = &_24;                      // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          _41 = deref_copy (*_22);         // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _42 = deref_copy (*_23);         // scope 8 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_43);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _43 = (*_41);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageLive(_44);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          _44 = (*_42);                    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+-         _21 = Le(move _43, move _44);    // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
++         _0 = Le(move _43, move _44);     // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_44);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_43);                // scope 9 at $SRC_DIR/core/src/cmp.rs:LL:COL
+          StorageDead(_24);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_23);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_22);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         _16 = move _21;                  // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:60: +0:76
+      }
+  
+      bb8: {
+-         StorageDead(_21);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+          StorageDead(_17);                // scope 1 at $DIR/slice_filter.rs:+0:75: +0:76
+-         _0 = move _16;                   // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:40: +0:76
+      }
+  }
+  
diff --git a/tests/mir-opt/slice_filter.variant_b-{closure#0}.CopyProp.diff b/tests/mir-opt/slice_filter.variant_b-{closure#0}.CopyProp.diff
new file mode 100644
index 000000000..5e4bdbdfa
--- /dev/null
+++ b/tests/mir-opt/slice_filter.variant_b-{closure#0}.CopyProp.diff
@@ -0,0 +1,139 @@
+- // MIR for `variant_b::{closure#0}` before CopyProp
++ // MIR for `variant_b::{closure#0}` after CopyProp
+  
+  fn variant_b::{closure#0}(_1: &mut [closure@$DIR/slice_filter.rs:12:25: 12:41], _2: &&(usize, usize, usize, usize)) -> bool {
+      let mut _0: bool;                    // return place in scope 0 at $DIR/slice_filter.rs:+0:42: +0:42
+      let _3: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+      let _4: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+      let _5: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+      let _6: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+      let mut _7: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:58
+      let mut _8: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:48
+      let mut _9: usize;                   // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:43
+      let mut _10: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:47: +0:48
+      let mut _11: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:52: +0:58
+      let mut _12: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:52: +0:53
+      let mut _13: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:57: +0:58
+      let mut _14: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:78
+      let mut _15: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:68
+      let mut _16: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:63
+      let mut _17: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:67: +0:68
+      let mut _18: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:72: +0:78
+      let mut _19: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:72: +0:73
+      let mut _20: usize;                  // in scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
+      let mut _21: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _22: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _23: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _24: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      scope 1 {
+          debug a => _3;                   // in scope 1 at $DIR/slice_filter.rs:+0:29: +0:30
+          debug b => _4;                   // in scope 1 at $DIR/slice_filter.rs:+0:32: +0:33
+          debug c => _5;                   // in scope 1 at $DIR/slice_filter.rs:+0:35: +0:36
+          debug d => _6;                   // in scope 1 at $DIR/slice_filter.rs:+0:38: +0:39
+      }
+  
+      bb0: {
+-         StorageLive(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+          _21 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+          _3 = ((*_21).0: usize);          // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+-         StorageLive(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+          _22 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+          _4 = ((*_22).1: usize);          // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+-         StorageLive(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+          _23 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+          _5 = ((*_23).2: usize);          // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+-         StorageLive(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+          _24 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+          _6 = ((*_24).3: usize);          // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+          StorageLive(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+          StorageLive(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
+-         StorageLive(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:43
+-         _9 = _3;                         // scope 1 at $DIR/slice_filter.rs:+0:42: +0:43
+-         StorageLive(_10);                // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
+-         _10 = _5;                        // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
+-         _8 = Le(move _9, move _10);      // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
+-         StorageDead(_10);                // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
+-         StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:47: +0:48
++         _8 = Le(_3, _5);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
+          switchInt(move _8) -> [0: bb4, otherwise: bb5]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+      }
+  
+      bb1: {
+          _0 = const true;                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+      }
+  
+      bb2: {
+          StorageLive(_14);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+          StorageLive(_15);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
+-         StorageLive(_16);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:63
+-         _16 = _5;                        // scope 1 at $DIR/slice_filter.rs:+0:62: +0:63
+-         StorageLive(_17);                // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
+-         _17 = _3;                        // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
+-         _15 = Le(move _16, move _17);    // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
+-         StorageDead(_17);                // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
+-         StorageDead(_16);                // scope 1 at $DIR/slice_filter.rs:+0:67: +0:68
++         _15 = Le(_5, _3);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
+          switchInt(move _15) -> [0: bb6, otherwise: bb7]; // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+      }
+  
+      bb3: {
+          StorageDead(_14);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+          StorageDead(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_6);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_5);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_4);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_3);                 // scope 0 at $DIR/slice_filter.rs:+0:77: +0:78
+          return;                          // scope 0 at $DIR/slice_filter.rs:+0:78: +0:78
+      }
+  
+      bb4: {
+          _7 = const false;                // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+          StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          goto -> bb2;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+      }
+  
+      bb5: {
+          StorageLive(_11);                // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
+-         StorageLive(_12);                // scope 1 at $DIR/slice_filter.rs:+0:52: +0:53
+-         _12 = _6;                        // scope 1 at $DIR/slice_filter.rs:+0:52: +0:53
+-         StorageLive(_13);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+-         _13 = _4;                        // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+-         _11 = Le(move _12, move _13);    // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
+-         StorageDead(_13);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+-         StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
++         _11 = Le(_6, _4);                // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
+          _7 = move _11;                   // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+          StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          switchInt(move _7) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+      }
+  
+      bb6: {
+          _14 = const false;               // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+      }
+  
+      bb7: {
+          StorageLive(_18);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
+-         StorageLive(_19);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:73
+-         _19 = _4;                        // scope 1 at $DIR/slice_filter.rs:+0:72: +0:73
+-         StorageLive(_20);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         _20 = _6;                        // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         _18 = Le(move _19, move _20);    // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
+-         StorageDead(_20);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_19);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
++         _18 = Le(_4, _6);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
+          _14 = move _18;                  // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+      }
+  
+      bb8: {
+          StorageDead(_18);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+          StorageDead(_15);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+          _0 = move _14;                   // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+      }
+  }
+  
diff --git a/tests/mir-opt/slice_filter.variant_b-{closure#0}.DestinationPropagation.diff b/tests/mir-opt/slice_filter.variant_b-{closure#0}.DestinationPropagation.diff
new file mode 100644
index 000000000..45af6600c
--- /dev/null
+++ b/tests/mir-opt/slice_filter.variant_b-{closure#0}.DestinationPropagation.diff
@@ -0,0 +1,109 @@
+- // MIR for `variant_b::{closure#0}` before DestinationPropagation
++ // MIR for `variant_b::{closure#0}` after DestinationPropagation
+  
+  fn variant_b::{closure#0}(_1: &mut [closure@$DIR/slice_filter.rs:12:25: 12:41], _2: &&(usize, usize, usize, usize)) -> bool {
+      let mut _0: bool;                    // return place in scope 0 at $DIR/slice_filter.rs:+0:42: +0:42
+      let _3: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+      let _4: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+      let _5: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+      let _6: usize;                       // in scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+      let mut _7: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:58
+      let mut _8: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:42: +0:48
+      let mut _9: bool;                    // in scope 0 at $DIR/slice_filter.rs:+0:52: +0:58
+      let mut _10: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:78
+      let mut _11: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:62: +0:68
+      let mut _12: bool;                   // in scope 0 at $DIR/slice_filter.rs:+0:72: +0:78
+      let mut _13: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _14: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _15: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      let mut _16: &(usize, usize, usize, usize); // in scope 0 at $DIR/slice_filter.rs:+0:26: +0:40
+      scope 1 {
+          debug a => _3;                   // in scope 1 at $DIR/slice_filter.rs:+0:29: +0:30
+          debug b => _4;                   // in scope 1 at $DIR/slice_filter.rs:+0:32: +0:33
+          debug c => _5;                   // in scope 1 at $DIR/slice_filter.rs:+0:35: +0:36
+          debug d => _6;                   // in scope 1 at $DIR/slice_filter.rs:+0:38: +0:39
+      }
+  
+      bb0: {
+          _13 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+          _3 = ((*_13).0: usize);          // scope 0 at $DIR/slice_filter.rs:+0:29: +0:30
+          _14 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+          _4 = ((*_14).1: usize);          // scope 0 at $DIR/slice_filter.rs:+0:32: +0:33
+          _15 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+          _5 = ((*_15).2: usize);          // scope 0 at $DIR/slice_filter.rs:+0:35: +0:36
+          _16 = deref_copy (*_2);          // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+          _6 = ((*_16).3: usize);          // scope 0 at $DIR/slice_filter.rs:+0:38: +0:39
+-         StorageLive(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+          StorageLive(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
+          _8 = Le(_3, _5);                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:48
+          switchInt(move _8) -> [0: bb4, otherwise: bb5]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+      }
+  
+      bb1: {
+          _0 = const true;                 // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+      }
+  
+      bb2: {
+-         StorageLive(_10);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+          StorageLive(_11);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
+          _11 = Le(_5, _3);                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:68
+          switchInt(move _11) -> [0: bb6, otherwise: bb7]; // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+      }
+  
+      bb3: {
+-         StorageDead(_10);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         StorageDead(_7);                 // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+          return;                          // scope 0 at $DIR/slice_filter.rs:+0:78: +0:78
+      }
+  
+      bb4: {
+-         StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          goto -> bb2;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+      }
+  
+      bb5: {
+-         StorageLive(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
+          _9 = Le(_6, _4);                 // scope 1 at $DIR/slice_filter.rs:+0:52: +0:58
+-         _7 = move _9;                    // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
+-         StorageDead(_9);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:42: +0:58
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+          StorageDead(_8);                 // scope 1 at $DIR/slice_filter.rs:+0:57: +0:58
+-         switchInt(move _7) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
++         switchInt(move _9) -> [0: bb2, otherwise: bb1]; // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+      }
+  
+      bb6: {
+-         _10 = const false;               // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
++         _0 = const false;                // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+      }
+  
+      bb7: {
+-         StorageLive(_12);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
+-         _12 = Le(_4, _6);                // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
+-         _10 = move _12;                  // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
++         _0 = Le(_4, _6);                 // scope 1 at $DIR/slice_filter.rs:+0:72: +0:78
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+          goto -> bb8;                     // scope 1 at $DIR/slice_filter.rs:+0:62: +0:78
+      }
+  
+      bb8: {
+-         StorageDead(_12);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+          StorageDead(_11);                // scope 1 at $DIR/slice_filter.rs:+0:77: +0:78
+-         _0 = move _10;                   // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
++         nop;                             // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+          goto -> bb3;                     // scope 1 at $DIR/slice_filter.rs:+0:42: +0:78
+      }
+  }
+  
diff --git a/tests/mir-opt/sroa.constant.ScalarReplacementOfAggregates.diff b/tests/mir-opt/sroa.constant.ScalarReplacementOfAggregates.diff
new file mode 100644
index 000000000..9e33215f2
--- /dev/null
+++ b/tests/mir-opt/sroa.constant.ScalarReplacementOfAggregates.diff
@@ -0,0 +1,46 @@
+- // MIR for `constant` before ScalarReplacementOfAggregates
++ // MIR for `constant` after ScalarReplacementOfAggregates
+  
+  fn constant() -> () {
+      let mut _0: ();                      // return place in scope 0 at $DIR/sroa.rs:+0:15: +0:15
+      let _1: (usize, u8);                 // in scope 0 at $DIR/sroa.rs:+2:9: +2:10
++     let _4: usize;                       // in scope 0 at $DIR/sroa.rs:+2:9: +2:10
++     let _5: u8;                          // in scope 0 at $DIR/sroa.rs:+2:9: +2:10
+      scope 1 {
+-         debug y => _1;                   // in scope 1 at $DIR/sroa.rs:+2:9: +2:10
++         debug y => (usize, u8){ .0 => _4, .1 => _5, }; // in scope 1 at $DIR/sroa.rs:+2:9: +2:10
+          let _2: usize;                   // in scope 1 at $DIR/sroa.rs:+3:9: +3:10
+          scope 2 {
+              debug t => _2;               // in scope 2 at $DIR/sroa.rs:+3:9: +3:10
+              let _3: u8;                  // in scope 2 at $DIR/sroa.rs:+4:9: +4:10
+              scope 3 {
+                  debug u => _3;           // in scope 3 at $DIR/sroa.rs:+4:9: +4:10
+              }
+          }
+      }
+  
+      bb0: {
+-         StorageLive(_1);                 // scope 0 at $DIR/sroa.rs:+2:9: +2:10
++         StorageLive(_4);                 // scope 0 at $DIR/sroa.rs:+2:9: +2:10
++         StorageLive(_5);                 // scope 0 at $DIR/sroa.rs:+2:9: +2:10
++         nop;                             // scope 0 at $DIR/sroa.rs:+2:9: +2:10
+          _1 = const _;                    // scope 0 at $DIR/sroa.rs:+2:13: +2:14
++         _4 = move (_1.0: usize);         // scope 1 at $DIR/sroa.rs:+3:9: +3:10
++         _5 = move (_1.1: u8);            // scope 1 at $DIR/sroa.rs:+3:9: +3:10
+          StorageLive(_2);                 // scope 1 at $DIR/sroa.rs:+3:9: +3:10
+-         _2 = (_1.0: usize);              // scope 1 at $DIR/sroa.rs:+3:13: +3:16
++         _2 = _4;                         // scope 1 at $DIR/sroa.rs:+3:13: +3:16
+          StorageLive(_3);                 // scope 2 at $DIR/sroa.rs:+4:9: +4:10
+-         _3 = (_1.1: u8);                 // scope 2 at $DIR/sroa.rs:+4:13: +4:16
++         _3 = _5;                         // scope 2 at $DIR/sroa.rs:+4:13: +4:16
+          _0 = const ();                   // scope 0 at $DIR/sroa.rs:+0:15: +5:2
+          StorageDead(_3);                 // scope 2 at $DIR/sroa.rs:+5:1: +5:2
+          StorageDead(_2);                 // scope 1 at $DIR/sroa.rs:+5:1: +5:2
+-         StorageDead(_1);                 // scope 0 at $DIR/sroa.rs:+5:1: +5:2
++         StorageDead(_4);                 // scope 0 at $DIR/sroa.rs:+5:1: +5:2
++         StorageDead(_5);                 // scope 0 at $DIR/sroa.rs:+5:1: +5:2
++         nop;                             // scope 0 at $DIR/sroa.rs:+5:1: +5:2
+          return;                          // scope 0 at $DIR/sroa.rs:+5:2: +5:2
+      }
+  }
+  
diff --git a/tests/mir-opt/sroa.copies.ScalarReplacementOfAggregates.diff b/tests/mir-opt/sroa.copies.ScalarReplacementOfAggregates.diff
new file mode 100644
index 000000000..976f6d44b
--- /dev/null
+++ b/tests/mir-opt/sroa.copies.ScalarReplacementOfAggregates.diff
@@ -0,0 +1,91 @@
+- // MIR for `copies` before ScalarReplacementOfAggregates
++ // MIR for `copies` after ScalarReplacementOfAggregates
+  
+  fn copies(_1: Foo) -> () {
+      debug x => _1;                       // in scope 0 at $DIR/sroa.rs:+0:11: +0:12
+      let mut _0: ();                      // return place in scope 0 at $DIR/sroa.rs:+0:19: +0:19
+      let _2: Foo;                         // in scope 0 at $DIR/sroa.rs:+1:9: +1:10
++     let _11: u8;                         // in scope 0 at $DIR/sroa.rs:+1:9: +1:10
++     let _12: ();                         // in scope 0 at $DIR/sroa.rs:+1:9: +1:10
++     let _13: &str;                       // in scope 0 at $DIR/sroa.rs:+1:9: +1:10
++     let _14: std::option::Option<isize>; // in scope 0 at $DIR/sroa.rs:+1:9: +1:10
+      scope 1 {
+-         debug y => _2;                   // in scope 1 at $DIR/sroa.rs:+1:9: +1:10
++         debug y => Foo{ .0 => _11, .1 => _12, .2 => _13, .3 => _14, }; // in scope 1 at $DIR/sroa.rs:+1:9: +1:10
+          let _3: u8;                      // in scope 1 at $DIR/sroa.rs:+2:9: +2:10
+          scope 2 {
+              debug t => _3;               // in scope 2 at $DIR/sroa.rs:+2:9: +2:10
+              let _4: &str;                // in scope 2 at $DIR/sroa.rs:+3:9: +3:10
+              scope 3 {
+                  debug u => _4;           // in scope 3 at $DIR/sroa.rs:+3:9: +3:10
+                  let _5: Foo;             // in scope 3 at $DIR/sroa.rs:+4:9: +4:10
++                 let _7: u8;              // in scope 3 at $DIR/sroa.rs:+4:9: +4:10
++                 let _8: ();              // in scope 3 at $DIR/sroa.rs:+4:9: +4:10
++                 let _9: &str;            // in scope 3 at $DIR/sroa.rs:+4:9: +4:10
++                 let _10: std::option::Option<isize>; // in scope 3 at $DIR/sroa.rs:+4:9: +4:10
+                  scope 4 {
+-                     debug z => _5;       // in scope 4 at $DIR/sroa.rs:+4:9: +4:10
++                     debug z => Foo{ .0 => _7, .1 => _8, .2 => _9, .3 => _10, }; // in scope 4 at $DIR/sroa.rs:+4:9: +4:10
+                      let _6: ();          // in scope 4 at $DIR/sroa.rs:+5:9: +5:10
+                      scope 5 {
+                          debug a => _6;   // in scope 5 at $DIR/sroa.rs:+5:9: +5:10
+                      }
+                  }
+              }
+          }
+      }
+  
+      bb0: {
+-         StorageLive(_2);                 // scope 0 at $DIR/sroa.rs:+1:9: +1:10
+-         _2 = _1;                         // scope 0 at $DIR/sroa.rs:+1:13: +1:14
++         StorageLive(_11);                // scope 0 at $DIR/sroa.rs:+1:9: +1:10
++         StorageLive(_12);                // scope 0 at $DIR/sroa.rs:+1:9: +1:10
++         StorageLive(_13);                // scope 0 at $DIR/sroa.rs:+1:9: +1:10
++         StorageLive(_14);                // scope 0 at $DIR/sroa.rs:+1:9: +1:10
++         nop;                             // scope 0 at $DIR/sroa.rs:+1:9: +1:10
++         _11 = (_1.0: u8);                // scope 0 at $DIR/sroa.rs:+1:13: +1:14
++         _12 = (_1.1: ());                // scope 0 at $DIR/sroa.rs:+1:13: +1:14
++         _13 = (_1.2: &str);              // scope 0 at $DIR/sroa.rs:+1:13: +1:14
++         _14 = (_1.3: std::option::Option<isize>); // scope 0 at $DIR/sroa.rs:+1:13: +1:14
++         nop;                             // scope 0 at $DIR/sroa.rs:+1:13: +1:14
+          StorageLive(_3);                 // scope 1 at $DIR/sroa.rs:+2:9: +2:10
+-         _3 = (_2.0: u8);                 // scope 1 at $DIR/sroa.rs:+2:13: +2:16
++         _3 = _11;                        // scope 1 at $DIR/sroa.rs:+2:13: +2:16
+          StorageLive(_4);                 // scope 2 at $DIR/sroa.rs:+3:9: +3:10
+-         _4 = (_2.2: &str);               // scope 2 at $DIR/sroa.rs:+3:13: +3:16
+-         StorageLive(_5);                 // scope 3 at $DIR/sroa.rs:+4:9: +4:10
+-         _5 = _2;                         // scope 3 at $DIR/sroa.rs:+4:13: +4:14
++         _4 = _13;                        // scope 2 at $DIR/sroa.rs:+3:13: +3:16
++         StorageLive(_7);                 // scope 3 at $DIR/sroa.rs:+4:9: +4:10
++         StorageLive(_8);                 // scope 3 at $DIR/sroa.rs:+4:9: +4:10
++         StorageLive(_9);                 // scope 3 at $DIR/sroa.rs:+4:9: +4:10
++         StorageLive(_10);                // scope 3 at $DIR/sroa.rs:+4:9: +4:10
++         nop;                             // scope 3 at $DIR/sroa.rs:+4:9: +4:10
++         _7 = _11;                        // scope 3 at $DIR/sroa.rs:+4:13: +4:14
++         _8 = _12;                        // scope 3 at $DIR/sroa.rs:+4:13: +4:14
++         _9 = _13;                        // scope 3 at $DIR/sroa.rs:+4:13: +4:14
++         _10 = _14;                       // scope 3 at $DIR/sroa.rs:+4:13: +4:14
++         nop;                             // scope 3 at $DIR/sroa.rs:+4:13: +4:14
+          StorageLive(_6);                 // scope 4 at $DIR/sroa.rs:+5:9: +5:10
+-         _6 = (_5.1: ());                 // scope 4 at $DIR/sroa.rs:+5:13: +5:16
++         _6 = _8;                         // scope 4 at $DIR/sroa.rs:+5:13: +5:16
+          _0 = const ();                   // scope 0 at $DIR/sroa.rs:+0:19: +6:2
+          StorageDead(_6);                 // scope 4 at $DIR/sroa.rs:+6:1: +6:2
+-         StorageDead(_5);                 // scope 3 at $DIR/sroa.rs:+6:1: +6:2
++         StorageDead(_7);                 // scope 3 at $DIR/sroa.rs:+6:1: +6:2
++         StorageDead(_8);                 // scope 3 at $DIR/sroa.rs:+6:1: +6:2
++         StorageDead(_9);                 // scope 3 at $DIR/sroa.rs:+6:1: +6:2
++         StorageDead(_10);                // scope 3 at $DIR/sroa.rs:+6:1: +6:2
++         nop;                             // scope 3 at $DIR/sroa.rs:+6:1: +6:2
+          StorageDead(_4);                 // scope 2 at $DIR/sroa.rs:+6:1: +6:2
+          StorageDead(_3);                 // scope 1 at $DIR/sroa.rs:+6:1: +6:2
+-         StorageDead(_2);                 // scope 0 at $DIR/sroa.rs:+6:1: +6:2
++         StorageDead(_11);                // scope 0 at $DIR/sroa.rs:+6:1: +6:2
++         StorageDead(_12);                // scope 0 at $DIR/sroa.rs:+6:1: +6:2
++         StorageDead(_13);                // scope 0 at $DIR/sroa.rs:+6:1: +6:2
++         StorageDead(_14);                // scope 0 at $DIR/sroa.rs:+6:1: +6:2
++         nop;                             // scope 0 at $DIR/sroa.rs:+6:1: +6:2
+          return;                          // scope 0 at $DIR/sroa.rs:+6:2: +6:2
+      }
+  }
+  
diff --git a/tests/mir-opt/sroa.dropping.ScalarReplacementOfAggregates.diff b/tests/mir-opt/sroa.dropping.ScalarReplacementOfAggregates.diff
index eb8830446..17a89e7d8 100644
--- a/tests/mir-opt/sroa.dropping.ScalarReplacementOfAggregates.diff
+++ b/tests/mir-opt/sroa.dropping.ScalarReplacementOfAggregates.diff
@@ -13,18 +13,12 @@
           StorageLive(_1);                 // scope 0 at $DIR/sroa.rs:+1:5: +1:32
           StorageLive(_2);                 // scope 0 at $DIR/sroa.rs:+1:5: +1:30
           StorageLive(_3);                 // scope 0 at $DIR/sroa.rs:+1:7: +1:13
-          Deinit(_3);                      // scope 0 at $DIR/sroa.rs:+1:7: +1:13
-          (_3.0: usize) = const 0_usize;   // scope 0 at $DIR/sroa.rs:+1:7: +1:13
+          _3 = Tag(const 0_usize);         // scope 0 at $DIR/sroa.rs:+1:7: +1:13
           StorageLive(_4);                 // scope 0 at $DIR/sroa.rs:+1:15: +1:21
-          Deinit(_4);                      // scope 0 at $DIR/sroa.rs:+1:15: +1:21
-          (_4.0: usize) = const 1_usize;   // scope 0 at $DIR/sroa.rs:+1:15: +1:21
+          _4 = Tag(const 1_usize);         // scope 0 at $DIR/sroa.rs:+1:15: +1:21
           StorageLive(_5);                 // scope 0 at $DIR/sroa.rs:+1:23: +1:29
-          Deinit(_5);                      // scope 0 at $DIR/sroa.rs:+1:23: +1:29
-          (_5.0: usize) = const 2_usize;   // scope 0 at $DIR/sroa.rs:+1:23: +1:29
-          Deinit(_2);                      // scope 0 at $DIR/sroa.rs:+1:5: +1:30
-          (_2.0: Tag) = move _3;           // scope 0 at $DIR/sroa.rs:+1:5: +1:30
-          (_2.1: Tag) = move _4;           // scope 0 at $DIR/sroa.rs:+1:5: +1:30
-          (_2.2: Tag) = move _5;           // scope 0 at $DIR/sroa.rs:+1:5: +1:30
+          _5 = Tag(const 2_usize);         // scope 0 at $DIR/sroa.rs:+1:23: +1:29
+          _2 = S(move _3, move _4, move _5); // scope 0 at $DIR/sroa.rs:+1:5: +1:30
           StorageDead(_5);                 // scope 0 at $DIR/sroa.rs:+1:29: +1:30
           StorageDead(_4);                 // scope 0 at $DIR/sroa.rs:+1:29: +1:30
           StorageDead(_3);                 // scope 0 at $DIR/sroa.rs:+1:29: +1:30
diff --git a/tests/mir-opt/sroa.enums.ScalarReplacementOfAggregates.diff b/tests/mir-opt/sroa.enums.ScalarReplacementOfAggregates.diff
index a5488c1ec..04d26162a 100644
--- a/tests/mir-opt/sroa.enums.ScalarReplacementOfAggregates.diff
+++ b/tests/mir-opt/sroa.enums.ScalarReplacementOfAggregates.diff
@@ -16,9 +16,7 @@
           StorageLive(_2);                 // scope 1 at $DIR/sroa.rs:+1:22: +1:29
           StorageLive(_3);                 // scope 1 at $DIR/sroa.rs:+1:27: +1:28
           _3 = _1;                         // scope 1 at $DIR/sroa.rs:+1:27: +1:28
-          Deinit(_2);                      // scope 1 at $DIR/sroa.rs:+1:22: +1:29
-          ((_2 as Some).0: usize) = move _3; // scope 1 at $DIR/sroa.rs:+1:22: +1:29
-          discriminant(_2) = 1;            // scope 1 at $DIR/sroa.rs:+1:22: +1:29
+          _2 = Option::<usize>::Some(move _3); // scope 1 at $DIR/sroa.rs:+1:22: +1:29
           StorageDead(_3);                 // scope 1 at $DIR/sroa.rs:+1:28: +1:29
           _4 = discriminant(_2);           // scope 1 at $DIR/sroa.rs:+1:12: +1:19
           switchInt(move _4) -> [1: bb1, otherwise: bb2]; // scope 1 at $DIR/sroa.rs:+1:12: +1:19
diff --git a/tests/mir-opt/sroa.escaping.ScalarReplacementOfAggregates.diff b/tests/mir-opt/sroa.escaping.ScalarReplacementOfAggregates.diff
index 64559b58f..fd691fdd1 100644
--- a/tests/mir-opt/sroa.escaping.ScalarReplacementOfAggregates.diff
+++ b/tests/mir-opt/sroa.escaping.ScalarReplacementOfAggregates.diff
@@ -3,45 +3,42 @@
   
   fn escaping() -> () {
       let mut _0: ();                      // return place in scope 0 at $DIR/sroa.rs:+0:19: +0:19
-      let _1: ();                          // in scope 0 at $DIR/sroa.rs:+2:5: +2:42
-      let mut _2: *const u32;              // in scope 0 at $DIR/sroa.rs:+2:7: +2:41
-      let _3: &u32;                        // in scope 0 at $DIR/sroa.rs:+2:7: +2:41
-      let _4: Escaping;                    // in scope 0 at $DIR/sroa.rs:+2:8: +2:39
-      let mut _5: u32;                     // in scope 0 at $DIR/sroa.rs:+2:34: +2:37
+      let _1: ();                          // in scope 0 at $DIR/sroa.rs:+1:5: +1:42
+      let mut _2: *const u32;              // in scope 0 at $DIR/sroa.rs:+1:7: +1:41
+      let _3: &u32;                        // in scope 0 at $DIR/sroa.rs:+1:7: +1:41
+      let _4: Escaping;                    // in scope 0 at $DIR/sroa.rs:+1:8: +1:39
+      let mut _5: u32;                     // in scope 0 at $DIR/sroa.rs:+1:34: +1:37
   
       bb0: {
-          StorageLive(_1);                 // scope 0 at $DIR/sroa.rs:+2:5: +2:42
-          StorageLive(_2);                 // scope 0 at $DIR/sroa.rs:+2:7: +2:41
-          StorageLive(_3);                 // scope 0 at $DIR/sroa.rs:+2:7: +2:41
-          StorageLive(_4);                 // scope 0 at $DIR/sroa.rs:+2:8: +2:39
-          StorageLive(_5);                 // scope 0 at $DIR/sroa.rs:+2:34: +2:37
-          _5 = g() -> bb1;                 // scope 0 at $DIR/sroa.rs:+2:34: +2:37
+          StorageLive(_1);                 // scope 0 at $DIR/sroa.rs:+1:5: +1:42
+          StorageLive(_2);                 // scope 0 at $DIR/sroa.rs:+1:7: +1:41
+          StorageLive(_3);                 // scope 0 at $DIR/sroa.rs:+1:7: +1:41
+          StorageLive(_4);                 // scope 0 at $DIR/sroa.rs:+1:8: +1:39
+          StorageLive(_5);                 // scope 0 at $DIR/sroa.rs:+1:34: +1:37
+          _5 = g() -> bb1;                 // scope 0 at $DIR/sroa.rs:+1:34: +1:37
                                            // mir::Constant
                                            // + span: $DIR/sroa.rs:78:34: 78:35
                                            // + literal: Const { ty: fn() -> u32 {g}, val: Value(<ZST>) }
       }
   
       bb1: {
-          Deinit(_4);                      // scope 0 at $DIR/sroa.rs:+2:8: +2:39
-          (_4.0: u32) = const 1_u32;       // scope 0 at $DIR/sroa.rs:+2:8: +2:39
-          (_4.1: u32) = const 2_u32;       // scope 0 at $DIR/sroa.rs:+2:8: +2:39
-          (_4.2: u32) = move _5;           // scope 0 at $DIR/sroa.rs:+2:8: +2:39
-          StorageDead(_5);                 // scope 0 at $DIR/sroa.rs:+2:38: +2:39
-          _3 = &(_4.0: u32);               // scope 0 at $DIR/sroa.rs:+2:7: +2:41
-          _2 = &raw const (*_3);           // scope 0 at $DIR/sroa.rs:+2:7: +2:41
-          _1 = f(move _2) -> bb2;          // scope 0 at $DIR/sroa.rs:+2:5: +2:42
+          _4 = Escaping { a: const 1_u32, b: const 2_u32, c: move _5 }; // scope 0 at $DIR/sroa.rs:+1:8: +1:39
+          StorageDead(_5);                 // scope 0 at $DIR/sroa.rs:+1:38: +1:39
+          _3 = &(_4.0: u32);               // scope 0 at $DIR/sroa.rs:+1:7: +1:41
+          _2 = &raw const (*_3);           // scope 0 at $DIR/sroa.rs:+1:7: +1:41
+          _1 = f(move _2) -> bb2;          // scope 0 at $DIR/sroa.rs:+1:5: +1:42
                                            // mir::Constant
                                            // + span: $DIR/sroa.rs:78:5: 78:6
                                            // + literal: Const { ty: fn(*const u32) {f}, val: Value(<ZST>) }
       }
   
       bb2: {
-          StorageDead(_2);                 // scope 0 at $DIR/sroa.rs:+2:41: +2:42
-          StorageDead(_4);                 // scope 0 at $DIR/sroa.rs:+2:42: +2:43
-          StorageDead(_3);                 // scope 0 at $DIR/sroa.rs:+2:42: +2:43
-          StorageDead(_1);                 // scope 0 at $DIR/sroa.rs:+2:42: +2:43
-          _0 = const ();                   // scope 0 at $DIR/sroa.rs:+0:19: +3:2
-          return;                          // scope 0 at $DIR/sroa.rs:+3:2: +3:2
+          StorageDead(_2);                 // scope 0 at $DIR/sroa.rs:+1:41: +1:42
+          StorageDead(_4);                 // scope 0 at $DIR/sroa.rs:+1:42: +1:43
+          StorageDead(_3);                 // scope 0 at $DIR/sroa.rs:+1:42: +1:43
+          StorageDead(_1);                 // scope 0 at $DIR/sroa.rs:+1:42: +1:43
+          _0 = const ();                   // scope 0 at $DIR/sroa.rs:+0:19: +2:2
+          return;                          // scope 0 at $DIR/sroa.rs:+2:2: +2:2
       }
   }
   
diff --git a/tests/mir-opt/sroa.flat.ScalarReplacementOfAggregates.diff b/tests/mir-opt/sroa.flat.ScalarReplacementOfAggregates.diff
index d4c04d5e6..69631fc02 100644
--- a/tests/mir-opt/sroa.flat.ScalarReplacementOfAggregates.diff
+++ b/tests/mir-opt/sroa.flat.ScalarReplacementOfAggregates.diff
@@ -35,28 +35,20 @@
 +         StorageLive(_9);                 // scope 0 at $DIR/sroa.rs:+1:30: +1:70
 +         StorageLive(_10);                // scope 0 at $DIR/sroa.rs:+1:30: +1:70
 +         StorageLive(_11);                // scope 0 at $DIR/sroa.rs:+1:30: +1:70
++         nop;                             // scope 0 at $DIR/sroa.rs:+1:30: +1:70
           StorageLive(_6);                 // scope 0 at $DIR/sroa.rs:+1:45: +1:47
-          Deinit(_6);                      // scope 0 at $DIR/sroa.rs:+1:45: +1:47
+          _6 = ();                         // scope 0 at $DIR/sroa.rs:+1:45: +1:47
           StorageLive(_7);                 // scope 0 at $DIR/sroa.rs:+1:60: +1:68
-          Deinit(_7);                      // scope 0 at $DIR/sroa.rs:+1:60: +1:68
-          ((_7 as Some).0: isize) = const -4_isize; // scope 0 at $DIR/sroa.rs:+1:60: +1:68
-          discriminant(_7) = 1;            // scope 0 at $DIR/sroa.rs:+1:60: +1:68
--         Deinit(_5);                      // scope 0 at $DIR/sroa.rs:+1:30: +1:70
--         (_5.0: u8) = const 5_u8;         // scope 0 at $DIR/sroa.rs:+1:30: +1:70
--         (_5.1: ()) = move _6;            // scope 0 at $DIR/sroa.rs:+1:30: +1:70
--         (_5.2: &str) = const "a";        // scope 0 at $DIR/sroa.rs:+1:30: +1:70
-+         Deinit(_8);                      // scope 0 at $DIR/sroa.rs:+1:30: +1:70
-+         Deinit(_9);                      // scope 0 at $DIR/sroa.rs:+1:30: +1:70
-+         Deinit(_10);                     // scope 0 at $DIR/sroa.rs:+1:30: +1:70
-+         Deinit(_11);                     // scope 0 at $DIR/sroa.rs:+1:30: +1:70
+          _7 = Option::<isize>::Some(const -4_isize); // scope 0 at $DIR/sroa.rs:+1:60: +1:68
+-         _5 = Foo { a: const 5_u8, b: move _6, c: const "a", d: move _7 }; // scope 0 at $DIR/sroa.rs:+1:30: +1:70
 +         _8 = const 5_u8;                 // scope 0 at $DIR/sroa.rs:+1:30: +1:70
 +         _9 = move _6;                    // scope 0 at $DIR/sroa.rs:+1:30: +1:70
 +         _10 = const "a";                 // scope 0 at $DIR/sroa.rs:+1:30: +1:70
                                            // mir::Constant
-                                           // + span: $DIR/sroa.rs:57:52: 57:55
+                                           // + span: $DIR/sroa.rs:53:52: 53:55
                                            // + literal: Const { ty: &str, val: Value(Slice(..)) }
--         (_5.3: std::option::Option<isize>) = move _7; // scope 0 at $DIR/sroa.rs:+1:30: +1:70
 +         _11 = move _7;                   // scope 0 at $DIR/sroa.rs:+1:30: +1:70
++         nop;                             // scope 0 at $DIR/sroa.rs:+1:30: +1:70
           StorageDead(_7);                 // scope 0 at $DIR/sroa.rs:+1:69: +1:70
           StorageDead(_6);                 // scope 0 at $DIR/sroa.rs:+1:69: +1:70
           StorageLive(_1);                 // scope 0 at $DIR/sroa.rs:+1:15: +1:16
@@ -76,6 +68,7 @@
 +         StorageDead(_9);                 // scope 0 at $DIR/sroa.rs:+1:70: +1:71
 +         StorageDead(_10);                // scope 0 at $DIR/sroa.rs:+1:70: +1:71
 +         StorageDead(_11);                // scope 0 at $DIR/sroa.rs:+1:70: +1:71
++         nop;                             // scope 0 at $DIR/sroa.rs:+1:70: +1:71
           _0 = const ();                   // scope 0 at $DIR/sroa.rs:+0:15: +6:2
           StorageDead(_4);                 // scope 0 at $DIR/sroa.rs:+6:1: +6:2
           StorageDead(_3);                 // scope 0 at $DIR/sroa.rs:+6:1: +6:2
diff --git a/tests/mir-opt/sroa.ref_copies.ScalarReplacementOfAggregates.diff b/tests/mir-opt/sroa.ref_copies.ScalarReplacementOfAggregates.diff
new file mode 100644
index 000000000..f0d62220d
--- /dev/null
+++ b/tests/mir-opt/sroa.ref_copies.ScalarReplacementOfAggregates.diff
@@ -0,0 +1,56 @@
+- // MIR for `ref_copies` before ScalarReplacementOfAggregates
++ // MIR for `ref_copies` after ScalarReplacementOfAggregates
+  
+  fn ref_copies(_1: &Foo) -> () {
+      debug x => _1;                       // in scope 0 at $DIR/sroa.rs:+0:15: +0:16
+      let mut _0: ();                      // return place in scope 0 at $DIR/sroa.rs:+0:24: +0:24
+      let _2: Foo;                         // in scope 0 at $DIR/sroa.rs:+1:9: +1:10
++     let _5: u8;                          // in scope 0 at $DIR/sroa.rs:+1:9: +1:10
++     let _6: ();                          // in scope 0 at $DIR/sroa.rs:+1:9: +1:10
++     let _7: &str;                        // in scope 0 at $DIR/sroa.rs:+1:9: +1:10
++     let _8: std::option::Option<isize>;  // in scope 0 at $DIR/sroa.rs:+1:9: +1:10
+      scope 1 {
+-         debug y => _2;                   // in scope 1 at $DIR/sroa.rs:+1:9: +1:10
++         debug y => Foo{ .0 => _5, .1 => _6, .2 => _7, .3 => _8, }; // in scope 1 at $DIR/sroa.rs:+1:9: +1:10
+          let _3: u8;                      // in scope 1 at $DIR/sroa.rs:+2:9: +2:10
+          scope 2 {
+              debug t => _3;               // in scope 2 at $DIR/sroa.rs:+2:9: +2:10
+              let _4: &str;                // in scope 2 at $DIR/sroa.rs:+3:9: +3:10
+              scope 3 {
+                  debug u => _4;           // in scope 3 at $DIR/sroa.rs:+3:9: +3:10
+              }
+          }
+      }
+  
+      bb0: {
+-         StorageLive(_2);                 // scope 0 at $DIR/sroa.rs:+1:9: +1:10
+-         _2 = (*_1);                      // scope 0 at $DIR/sroa.rs:+1:13: +1:15
++         StorageLive(_5);                 // scope 0 at $DIR/sroa.rs:+1:9: +1:10
++         StorageLive(_6);                 // scope 0 at $DIR/sroa.rs:+1:9: +1:10
++         StorageLive(_7);                 // scope 0 at $DIR/sroa.rs:+1:9: +1:10
++         StorageLive(_8);                 // scope 0 at $DIR/sroa.rs:+1:9: +1:10
++         nop;                             // scope 0 at $DIR/sroa.rs:+1:9: +1:10
++         _5 = ((*_1).0: u8);              // scope 0 at $DIR/sroa.rs:+1:13: +1:15
++         _6 = ((*_1).1: ());              // scope 0 at $DIR/sroa.rs:+1:13: +1:15
++         _7 = ((*_1).2: &str);            // scope 0 at $DIR/sroa.rs:+1:13: +1:15
++         _8 = ((*_1).3: std::option::Option<isize>); // scope 0 at $DIR/sroa.rs:+1:13: +1:15
++         nop;                             // scope 0 at $DIR/sroa.rs:+1:13: +1:15
+          StorageLive(_3);                 // scope 1 at $DIR/sroa.rs:+2:9: +2:10
+-         _3 = (_2.0: u8);                 // scope 1 at $DIR/sroa.rs:+2:13: +2:16
++         _3 = _5;                         // scope 1 at $DIR/sroa.rs:+2:13: +2:16
+          StorageLive(_4);                 // scope 2 at $DIR/sroa.rs:+3:9: +3:10
+-         _4 = (_2.2: &str);               // scope 2 at $DIR/sroa.rs:+3:13: +3:16
++         _4 = _7;                         // scope 2 at $DIR/sroa.rs:+3:13: +3:16
+          _0 = const ();                   // scope 0 at $DIR/sroa.rs:+0:24: +4:2
+          StorageDead(_4);                 // scope 2 at $DIR/sroa.rs:+4:1: +4:2
+          StorageDead(_3);                 // scope 1 at $DIR/sroa.rs:+4:1: +4:2
+-         StorageDead(_2);                 // scope 0 at $DIR/sroa.rs:+4:1: +4:2
++         StorageDead(_5);                 // scope 0 at $DIR/sroa.rs:+4:1: +4:2
++         StorageDead(_6);                 // scope 0 at $DIR/sroa.rs:+4:1: +4:2
++         StorageDead(_7);                 // scope 0 at $DIR/sroa.rs:+4:1: +4:2
++         StorageDead(_8);                 // scope 0 at $DIR/sroa.rs:+4:1: +4:2
++         nop;                             // scope 0 at $DIR/sroa.rs:+4:1: +4:2
+          return;                          // scope 0 at $DIR/sroa.rs:+4:2: +4:2
+      }
+  }
+  
diff --git a/tests/mir-opt/sroa.rs b/tests/mir-opt/sroa.rs
index ff8deb40d..fff92cf8d 100644
--- a/tests/mir-opt/sroa.rs
+++ b/tests/mir-opt/sroa.rs
@@ -12,17 +12,14 @@ impl Drop for Tag {
     fn drop(&mut self) {}
 }
 
-// EMIT_MIR sroa.dropping.ScalarReplacementOfAggregates.diff
 pub fn dropping() {
     S(Tag(0), Tag(1), Tag(2)).1;
 }
 
-// EMIT_MIR sroa.enums.ScalarReplacementOfAggregates.diff
 pub fn enums(a: usize) -> usize {
     if let Some(a) = Some(a) { a } else { 0 }
 }
 
-// EMIT_MIR sroa.structs.ScalarReplacementOfAggregates.diff
 pub fn structs(a: f32) -> f32 {
     struct U {
         _foo: usize,
@@ -32,7 +29,6 @@ pub fn structs(a: f32) -> f32 {
     U { _foo: 0, a }.a
 }
 
-// EMIT_MIR sroa.unions.ScalarReplacementOfAggregates.diff
 pub fn unions(a: f32) -> u32 {
     union Repr {
         f: f32,
@@ -41,6 +37,7 @@ pub fn unions(a: f32) -> u32 {
     unsafe { Repr { f: a }.u }
 }
 
+#[derive(Copy, Clone)]
 struct Foo {
     a: u8,
     b: (),
@@ -52,7 +49,6 @@ fn g() -> u32 {
     3
 }
 
-// EMIT_MIR sroa.flat.ScalarReplacementOfAggregates.diff
 pub fn flat() {
     let Foo { a, b, c, d } = Foo { a: 5, b: (), c: "a", d: Some(-4) };
     let _ = a;
@@ -72,12 +68,37 @@ fn f(a: *const u32) {
     println!("{}", unsafe { *a.add(2) });
 }
 
-// EMIT_MIR sroa.escaping.ScalarReplacementOfAggregates.diff
+// `f` uses the `&e.a` to access `e.c`. This is UB according to Miri today; however,
+// T-opsem has not finalized that decision and as such rustc should not rely on
+// it. If SROA were to rely on it, it would be (almost) correct to turn `e` into
+// three distinct locals - one for each field - and pass a reference to only one
+// of them to `f`. However, this would lead to a miscompilation because `b` and `c`
+// might no longer appear right after `a` in memory.
 pub fn escaping() {
-    // Verify this struct is not flattened.
     f(&Escaping { a: 1, b: 2, c: g() }.a);
 }
 
+fn copies(x: Foo) {
+    let y = x;
+    let t = y.a;
+    let u = y.c;
+    let z = y;
+    let a = z.b;
+}
+
+fn ref_copies(x: &Foo) {
+    let y = *x;
+    let t = y.a;
+    let u = y.c;
+}
+
+fn constant() {
+    const U: (usize, u8) = (5, 9);
+    let y = U;
+    let t = y.0;
+    let u = y.1;
+}
+
 fn main() {
     dropping();
     enums(5);
@@ -85,4 +106,17 @@ fn main() {
     unions(5.);
     flat();
     escaping();
+    copies(Foo { a: 5, b: (), c: "a", d: Some(-4) });
+    ref_copies(&Foo { a: 5, b: (), c: "a", d: Some(-4) });
+    constant();
 }
+
+// EMIT_MIR sroa.dropping.ScalarReplacementOfAggregates.diff
+// EMIT_MIR sroa.enums.ScalarReplacementOfAggregates.diff
+// EMIT_MIR sroa.structs.ScalarReplacementOfAggregates.diff
+// EMIT_MIR sroa.unions.ScalarReplacementOfAggregates.diff
+// EMIT_MIR sroa.flat.ScalarReplacementOfAggregates.diff
+// EMIT_MIR sroa.escaping.ScalarReplacementOfAggregates.diff
+// EMIT_MIR sroa.copies.ScalarReplacementOfAggregates.diff
+// EMIT_MIR sroa.ref_copies.ScalarReplacementOfAggregates.diff
+// EMIT_MIR sroa.constant.ScalarReplacementOfAggregates.diff
diff --git a/tests/mir-opt/sroa.structs.ScalarReplacementOfAggregates.diff b/tests/mir-opt/sroa.structs.ScalarReplacementOfAggregates.diff
index 69d74c351..2c63d8b26 100644
--- a/tests/mir-opt/sroa.structs.ScalarReplacementOfAggregates.diff
+++ b/tests/mir-opt/sroa.structs.ScalarReplacementOfAggregates.diff
@@ -13,21 +13,20 @@
 -         StorageLive(_2);                 // scope 0 at $DIR/sroa.rs:+6:5: +6:21
 +         StorageLive(_4);                 // scope 0 at $DIR/sroa.rs:+6:5: +6:21
 +         StorageLive(_5);                 // scope 0 at $DIR/sroa.rs:+6:5: +6:21
++         nop;                             // scope 0 at $DIR/sroa.rs:+6:5: +6:21
           StorageLive(_3);                 // scope 0 at $DIR/sroa.rs:+6:18: +6:19
           _3 = _1;                         // scope 0 at $DIR/sroa.rs:+6:18: +6:19
--         Deinit(_2);                      // scope 0 at $DIR/sroa.rs:+6:5: +6:21
--         (_2.0: usize) = const 0_usize;   // scope 0 at $DIR/sroa.rs:+6:5: +6:21
--         (_2.1: f32) = move _3;           // scope 0 at $DIR/sroa.rs:+6:5: +6:21
-+         Deinit(_4);                      // scope 0 at $DIR/sroa.rs:+6:5: +6:21
-+         Deinit(_5);                      // scope 0 at $DIR/sroa.rs:+6:5: +6:21
+-         _2 = U { _foo: const 0_usize, a: move _3 }; // scope 0 at $DIR/sroa.rs:+6:5: +6:21
 +         _4 = const 0_usize;              // scope 0 at $DIR/sroa.rs:+6:5: +6:21
 +         _5 = move _3;                    // scope 0 at $DIR/sroa.rs:+6:5: +6:21
++         nop;                             // scope 0 at $DIR/sroa.rs:+6:5: +6:21
           StorageDead(_3);                 // scope 0 at $DIR/sroa.rs:+6:20: +6:21
 -         _0 = (_2.1: f32);                // scope 0 at $DIR/sroa.rs:+6:5: +6:23
 -         StorageDead(_2);                 // scope 0 at $DIR/sroa.rs:+7:1: +7:2
 +         _0 = _5;                         // scope 0 at $DIR/sroa.rs:+6:5: +6:23
 +         StorageDead(_4);                 // scope 0 at $DIR/sroa.rs:+7:1: +7:2
 +         StorageDead(_5);                 // scope 0 at $DIR/sroa.rs:+7:1: +7:2
++         nop;                             // scope 0 at $DIR/sroa.rs:+7:1: +7:2
           return;                          // scope 0 at $DIR/sroa.rs:+7:2: +7:2
       }
   }
diff --git a/tests/mir-opt/sroa.unions.ScalarReplacementOfAggregates.diff b/tests/mir-opt/sroa.unions.ScalarReplacementOfAggregates.diff
index 03ca976df..adfb01385 100644
--- a/tests/mir-opt/sroa.unions.ScalarReplacementOfAggregates.diff
+++ b/tests/mir-opt/sroa.unions.ScalarReplacementOfAggregates.diff
@@ -13,8 +13,7 @@
           StorageLive(_2);                 // scope 1 at $DIR/sroa.rs:+5:14: +5:27
           StorageLive(_3);                 // scope 1 at $DIR/sroa.rs:+5:24: +5:25
           _3 = _1;                         // scope 1 at $DIR/sroa.rs:+5:24: +5:25
-          Deinit(_2);                      // scope 1 at $DIR/sroa.rs:+5:14: +5:27
-          (_2.0: f32) = move _3;           // scope 1 at $DIR/sroa.rs:+5:14: +5:27
+          _2 = Repr { f: move _3 };        // scope 1 at $DIR/sroa.rs:+5:14: +5:27
           StorageDead(_3);                 // scope 1 at $DIR/sroa.rs:+5:26: +5:27
           _0 = (_2.1: u32);                // scope 1 at $DIR/sroa.rs:+5:14: +5:29
           StorageDead(_2);                 // scope 0 at $DIR/sroa.rs:+6:1: +6:2
diff --git a/tests/mir-opt/try_identity_e2e.new.PreCodegen.after.mir b/tests/mir-opt/try_identity_e2e.new.PreCodegen.after.mir
index b254bfeb7..b9cc10575 100644
--- a/tests/mir-opt/try_identity_e2e.new.PreCodegen.after.mir
+++ b/tests/mir-opt/try_identity_e2e.new.PreCodegen.after.mir
@@ -5,11 +5,11 @@ fn new(_1: Result<T, E>) -> Result<T, E> {
     let mut _0: std::result::Result<T, E>; // return place in scope 0 at $DIR/try_identity_e2e.rs:+0:34: +0:46
     let mut _2: std::ops::ControlFlow<E, T>; // in scope 0 at $DIR/try_identity_e2e.rs:+2:15: +7:10
     let mut _3: isize;                   // in scope 0 at $DIR/try_identity_e2e.rs:+4:17: +4:22
-    let mut _4: T;                       // in scope 0 at $DIR/try_identity_e2e.rs:+4:48: +4:49
-    let mut _5: E;                       // in scope 0 at $DIR/try_identity_e2e.rs:+5:46: +5:47
+    let _4: T;                           // in scope 0 at $DIR/try_identity_e2e.rs:+4:20: +4:21
+    let _5: E;                           // in scope 0 at $DIR/try_identity_e2e.rs:+5:21: +5:22
     let mut _6: isize;                   // in scope 0 at $DIR/try_identity_e2e.rs:+8:13: +8:37
     let _7: T;                           // in scope 0 at $DIR/try_identity_e2e.rs:+8:35: +8:36
-    let mut _8: E;                       // in scope 0 at $DIR/try_identity_e2e.rs:+9:49: +9:50
+    let _8: E;                           // in scope 0 at $DIR/try_identity_e2e.rs:+9:32: +9:33
     scope 1 {
         debug v => _4;                   // in scope 1 at $DIR/try_identity_e2e.rs:+4:20: +4:21
     }
@@ -26,45 +26,40 @@ fn new(_1: Result<T, E>) -> Result<T, E> {
     bb0: {
         StorageLive(_2);                 // scope 0 at $DIR/try_identity_e2e.rs:+2:15: +7:10
         _3 = discriminant(_1);           // scope 0 at $DIR/try_identity_e2e.rs:+3:19: +3:20
-        switchInt(move _3) -> [0: bb2, 1: bb1, otherwise: bb4]; // scope 0 at $DIR/try_identity_e2e.rs:+3:13: +3:20
+        switchInt(move _3) -> [0: bb2, 1: bb1, otherwise: bb5]; // scope 0 at $DIR/try_identity_e2e.rs:+3:13: +3:20
     }
 
     bb1: {
         _5 = move ((_1 as Err).0: E);    // scope 0 at $DIR/try_identity_e2e.rs:+5:21: +5:22
-        Deinit(_2);                      // scope 2 at $DIR/try_identity_e2e.rs:+5:27: +5:48
-        ((_2 as Break).0: E) = move _5;  // scope 2 at $DIR/try_identity_e2e.rs:+5:27: +5:48
-        discriminant(_2) = 1;            // scope 2 at $DIR/try_identity_e2e.rs:+5:27: +5:48
-        _6 = discriminant(_2);           // scope 0 at $DIR/try_identity_e2e.rs:+2:15: +7:10
-        switchInt(move _6) -> [0: bb5, 1: bb3, otherwise: bb4]; // scope 0 at $DIR/try_identity_e2e.rs:+2:9: +7:10
+        _2 = ControlFlow::<E, T>::Break(move _5); // scope 2 at $DIR/try_identity_e2e.rs:+5:27: +5:48
+        goto -> bb3;                     // scope 0 at $DIR/try_identity_e2e.rs:+5:47: +5:48
     }
 
     bb2: {
         _4 = move ((_1 as Ok).0: T);     // scope 0 at $DIR/try_identity_e2e.rs:+4:20: +4:21
-        Deinit(_2);                      // scope 1 at $DIR/try_identity_e2e.rs:+4:26: +4:50
-        ((_2 as Continue).0: T) = move _4; // scope 1 at $DIR/try_identity_e2e.rs:+4:26: +4:50
-        discriminant(_2) = 0;            // scope 1 at $DIR/try_identity_e2e.rs:+4:26: +4:50
-        _6 = discriminant(_2);           // scope 0 at $DIR/try_identity_e2e.rs:+2:15: +7:10
-        switchInt(move _6) -> [0: bb5, 1: bb3, otherwise: bb4]; // scope 0 at $DIR/try_identity_e2e.rs:+2:9: +7:10
+        _2 = ControlFlow::<E, T>::Continue(move _4); // scope 1 at $DIR/try_identity_e2e.rs:+4:26: +4:50
+        goto -> bb3;                     // scope 0 at $DIR/try_identity_e2e.rs:+4:49: +4:50
     }
 
     bb3: {
+        _6 = discriminant(_2);           // scope 0 at $DIR/try_identity_e2e.rs:+2:15: +7:10
+        switchInt(move _6) -> [0: bb6, 1: bb4, otherwise: bb5]; // scope 0 at $DIR/try_identity_e2e.rs:+2:9: +7:10
+    }
+
+    bb4: {
         _8 = move ((_2 as Break).0: E);  // scope 0 at $DIR/try_identity_e2e.rs:+9:32: +9:33
-        Deinit(_0);                      // scope 4 at $DIR/try_identity_e2e.rs:+9:45: +9:51
-        ((_0 as Err).0: E) = move _8;    // scope 4 at $DIR/try_identity_e2e.rs:+9:45: +9:51
-        discriminant(_0) = 1;            // scope 4 at $DIR/try_identity_e2e.rs:+9:45: +9:51
+        _0 = Result::<T, E>::Err(move _8); // scope 4 at $DIR/try_identity_e2e.rs:+9:45: +9:51
         StorageDead(_2);                 // scope 0 at $DIR/try_identity_e2e.rs:+12:1: +12:2
         return;                          // scope 0 at $DIR/try_identity_e2e.rs:+12:1: +12:2
     }
 
-    bb4: {
+    bb5: {
         unreachable;                     // scope 0 at $DIR/try_identity_e2e.rs:+2:15: +7:10
     }
 
-    bb5: {
+    bb6: {
         _7 = move ((_2 as Continue).0: T); // scope 0 at $DIR/try_identity_e2e.rs:+8:35: +8:36
-        Deinit(_0);                      // scope 0 at $DIR/try_identity_e2e.rs:+1:5: +11:6
-        ((_0 as Ok).0: T) = move _7;     // scope 0 at $DIR/try_identity_e2e.rs:+1:5: +11:6
-        discriminant(_0) = 0;            // scope 0 at $DIR/try_identity_e2e.rs:+1:5: +11:6
+        _0 = Result::<T, E>::Ok(move _7); // scope 0 at $DIR/try_identity_e2e.rs:+1:5: +11:6
         StorageDead(_2);                 // scope 0 at $DIR/try_identity_e2e.rs:+12:1: +12:2
         return;                          // scope 0 at $DIR/try_identity_e2e.rs:+12:1: +12:2
     }
diff --git a/tests/mir-opt/try_identity_e2e.old.PreCodegen.after.mir b/tests/mir-opt/try_identity_e2e.old.PreCodegen.after.mir
index cdbc0681c..d88ae5ac9 100644
--- a/tests/mir-opt/try_identity_e2e.old.PreCodegen.after.mir
+++ b/tests/mir-opt/try_identity_e2e.old.PreCodegen.after.mir
@@ -5,7 +5,7 @@ fn old(_1: Result<T, E>) -> Result<T, E> {
     let mut _0: std::result::Result<T, E>; // return place in scope 0 at $DIR/try_identity_e2e.rs:+0:34: +0:46
     let mut _2: isize;                   // in scope 0 at $DIR/try_identity_e2e.rs:+3:13: +3:18
     let _3: T;                           // in scope 0 at $DIR/try_identity_e2e.rs:+3:16: +3:17
-    let mut _4: E;                       // in scope 0 at $DIR/try_identity_e2e.rs:+4:34: +4:35
+    let _4: E;                           // in scope 0 at $DIR/try_identity_e2e.rs:+4:17: +4:18
     scope 1 {
         debug v => _3;                   // in scope 1 at $DIR/try_identity_e2e.rs:+3:16: +3:17
     }
@@ -20,9 +20,7 @@ fn old(_1: Result<T, E>) -> Result<T, E> {
 
     bb1: {
         _4 = move ((_1 as Err).0: E);    // scope 0 at $DIR/try_identity_e2e.rs:+4:17: +4:18
-        Deinit(_0);                      // scope 2 at $DIR/try_identity_e2e.rs:+4:30: +4:36
-        ((_0 as Err).0: E) = move _4;    // scope 2 at $DIR/try_identity_e2e.rs:+4:30: +4:36
-        discriminant(_0) = 1;            // scope 2 at $DIR/try_identity_e2e.rs:+4:30: +4:36
+        _0 = Result::<T, E>::Err(move _4); // scope 2 at $DIR/try_identity_e2e.rs:+4:30: +4:36
         return;                          // scope 0 at $DIR/try_identity_e2e.rs:+7:1: +7:2
     }
 
@@ -32,9 +30,7 @@ fn old(_1: Result<T, E>) -> Result<T, E> {
 
     bb3: {
         _3 = move ((_1 as Ok).0: T);     // scope 0 at $DIR/try_identity_e2e.rs:+3:16: +3:17
-        Deinit(_0);                      // scope 0 at $DIR/try_identity_e2e.rs:+1:5: +6:6
-        ((_0 as Ok).0: T) = move _3;     // scope 0 at $DIR/try_identity_e2e.rs:+1:5: +6:6
-        discriminant(_0) = 0;            // scope 0 at $DIR/try_identity_e2e.rs:+1:5: +6:6
+        _0 = Result::<T, E>::Ok(move _3); // scope 0 at $DIR/try_identity_e2e.rs:+1:5: +6:6
         return;                          // scope 0 at $DIR/try_identity_e2e.rs:+7:1: +7:2
     }
 }
diff --git a/tests/mir-opt/uninhabited_enum_branching.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir b/tests/mir-opt/uninhabited_enum_branching.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
index 39ec05277..03f37b14b 100644
--- a/tests/mir-opt/uninhabited_enum_branching.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
+++ b/tests/mir-opt/uninhabited_enum_branching.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
@@ -15,8 +15,7 @@ fn main() -> () {
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:5: +5:6
         StorageLive(_2);                 // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:11: +1:19
-        Deinit(_2);                      // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:11: +1:19
-        discriminant(_2) = 2;            // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:11: +1:19
+        _2 = Test1::C;                   // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:11: +1:19
         _3 = discriminant(_2);           // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:11: +1:19
         switchInt(move _3) -> [2: bb1, otherwise: bb2]; // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:5: +1:19
     }
@@ -33,8 +32,7 @@ fn main() -> () {
         StorageDead(_1);                 // scope 0 at $DIR/uninhabited_enum_branching.rs:+5:6: +5:7
         StorageLive(_6);                 // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:5: +10:6
         StorageLive(_7);                 // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:11: +7:19
-        Deinit(_7);                      // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:11: +7:19
-        discriminant(_7) = 0;            // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:11: +7:19
+        _7 = Test2::D;                   // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:11: +7:19
         _8 = discriminant(_7);           // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:11: +7:19
         switchInt(move _8) -> [4: bb5, 5: bb3, otherwise: bb4]; // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:5: +7:19
     }
diff --git a/tests/mir-opt/uninhabited_enum_branching.main.UninhabitedEnumBranching.diff b/tests/mir-opt/uninhabited_enum_branching.main.UninhabitedEnumBranching.diff
index 598413a1d..671e11622 100644
--- a/tests/mir-opt/uninhabited_enum_branching.main.UninhabitedEnumBranching.diff
+++ b/tests/mir-opt/uninhabited_enum_branching.main.UninhabitedEnumBranching.diff
@@ -16,8 +16,7 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:5: +5:6
           StorageLive(_2);                 // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:11: +1:19
-          Deinit(_2);                      // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:11: +1:19
-          discriminant(_2) = 2;            // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:11: +1:19
+          _2 = Test1::C;                   // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:11: +1:19
           _3 = discriminant(_2);           // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:11: +1:19
 -         switchInt(move _3) -> [0: bb3, 1: bb4, 2: bb1, otherwise: bb2]; // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:5: +1:19
 +         switchInt(move _3) -> [2: bb1, otherwise: bb2]; // scope 0 at $DIR/uninhabited_enum_branching.rs:+1:5: +1:19
@@ -62,8 +61,7 @@
           StorageDead(_1);                 // scope 0 at $DIR/uninhabited_enum_branching.rs:+5:6: +5:7
           StorageLive(_6);                 // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:5: +10:6
           StorageLive(_7);                 // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:11: +7:19
-          Deinit(_7);                      // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:11: +7:19
-          discriminant(_7) = 0;            // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:11: +7:19
+          _7 = Test2::D;                   // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:11: +7:19
           _8 = discriminant(_7);           // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:11: +7:19
           switchInt(move _8) -> [4: bb8, 5: bb6, otherwise: bb7]; // scope 0 at $DIR/uninhabited_enum_branching.rs:+7:5: +7:19
       }
diff --git a/tests/mir-opt/uninhabited_enum_branching2.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir b/tests/mir-opt/uninhabited_enum_branching2.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
index c8cd6f6c1..eb2a76ed1 100644
--- a/tests/mir-opt/uninhabited_enum_branching2.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
+++ b/tests/mir-opt/uninhabited_enum_branching2.main.SimplifyCfg-after-uninhabited-enum-branching.after.mir
@@ -22,11 +22,8 @@ fn main() -> () {
     bb0: {
         StorageLive(_1);                 // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:9: +1:13
         StorageLive(_2);                 // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:38: +1:46
-        Deinit(_2);                      // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:38: +1:46
-        discriminant(_2) = 2;            // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:38: +1:46
-        Deinit(_1);                      // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:16: +1:48
-        (_1.0: u32) = const 51_u32;      // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:16: +1:48
-        (_1.1: Test1) = move _2;         // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:16: +1:48
+        _2 = Test1::C;                   // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:38: +1:46
+        _1 = Plop { xx: const 51_u32, test1: move _2 }; // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:16: +1:48
         StorageDead(_2);                 // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:47: +1:48
         StorageLive(_3);                 // scope 1 at $DIR/uninhabited_enum_branching2.rs:+3:5: +8:6
         StorageLive(_4);                 // scope 1 at $DIR/uninhabited_enum_branching2.rs:+3:11: +3:22
diff --git a/tests/mir-opt/uninhabited_enum_branching2.main.UninhabitedEnumBranching.diff b/tests/mir-opt/uninhabited_enum_branching2.main.UninhabitedEnumBranching.diff
index 2aee6d268..4e797774d 100644
--- a/tests/mir-opt/uninhabited_enum_branching2.main.UninhabitedEnumBranching.diff
+++ b/tests/mir-opt/uninhabited_enum_branching2.main.UninhabitedEnumBranching.diff
@@ -23,11 +23,8 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:9: +1:13
           StorageLive(_2);                 // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:38: +1:46
-          Deinit(_2);                      // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:38: +1:46
-          discriminant(_2) = 2;            // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:38: +1:46
-          Deinit(_1);                      // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:16: +1:48
-          (_1.0: u32) = const 51_u32;      // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:16: +1:48
-          (_1.1: Test1) = move _2;         // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:16: +1:48
+          _2 = Test1::C;                   // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:38: +1:46
+          _1 = Plop { xx: const 51_u32, test1: move _2 }; // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:16: +1:48
           StorageDead(_2);                 // scope 0 at $DIR/uninhabited_enum_branching2.rs:+1:47: +1:48
           StorageLive(_3);                 // scope 1 at $DIR/uninhabited_enum_branching2.rs:+3:5: +8:6
           StorageLive(_4);                 // scope 1 at $DIR/uninhabited_enum_branching2.rs:+3:11: +3:22
diff --git a/tests/mir-opt/unusual_item_types.Test-X-{constructor#0}.built.after.mir b/tests/mir-opt/unusual_item_types.Test-X-{constructor#0}.built.after.mir
index ee0296763..8b271135c 100644
--- a/tests/mir-opt/unusual_item_types.Test-X-{constructor#0}.built.after.mir
+++ b/tests/mir-opt/unusual_item_types.Test-X-{constructor#0}.built.after.mir
@@ -4,9 +4,7 @@ fn Test::X(_1: usize) -> Test {
     let mut _0: Test;                    // return place in scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
 
     bb0: {
-        Deinit(_0);                      // scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
-        ((_0 as X).0: usize) = move _1;  // scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
-        discriminant(_0) = 0;            // scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
+        _0 = Test::X(move _1);           // scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
         return;                          // scope 0 at $DIR/unusual_item_types.rs:+0:5: +0:6
     }
 }
diff --git a/tests/mir-opt/while_let_loops.change_loop_body.ConstProp.diff b/tests/mir-opt/while_let_loops.change_loop_body.ConstProp.diff
index bb1de59d4..a4f2d8c84 100644
--- a/tests/mir-opt/while_let_loops.change_loop_body.ConstProp.diff
+++ b/tests/mir-opt/while_let_loops.change_loop_body.ConstProp.diff
@@ -16,8 +16,7 @@
           StorageLive(_1);                 // scope 0 at $DIR/while_let_loops.rs:+1:9: +1:15
           _1 = const 0_i32;                // scope 0 at $DIR/while_let_loops.rs:+1:18: +1:19
           StorageLive(_2);                 // scope 2 at $DIR/while_let_loops.rs:+2:28: +2:32
-          Deinit(_2);                      // scope 2 at $DIR/while_let_loops.rs:+2:28: +2:32
-          discriminant(_2) = 0;            // scope 2 at $DIR/while_let_loops.rs:+2:28: +2:32
+          _2 = Option::<u32>::None;        // scope 2 at $DIR/while_let_loops.rs:+2:28: +2:32
 -         _3 = discriminant(_2);           // scope 2 at $DIR/while_let_loops.rs:+2:15: +2:25
 -         switchInt(move _3) -> [1: bb1, otherwise: bb3]; // scope 2 at $DIR/while_let_loops.rs:+2:15: +2:25
 +         _3 = const 0_isize;              // scope 2 at $DIR/while_let_loops.rs:+2:15: +2:25
diff --git a/tests/mir-opt/while_storage.while_loop.PreCodegen.after.mir b/tests/mir-opt/while_storage.while_loop.PreCodegen.after.mir
index b95d91b13..318119bd4 100644
--- a/tests/mir-opt/while_storage.while_loop.PreCodegen.after.mir
+++ b/tests/mir-opt/while_storage.while_loop.PreCodegen.after.mir
@@ -4,9 +4,7 @@ fn while_loop(_1: bool) -> () {
     debug c => _1;                       // in scope 0 at $DIR/while_storage.rs:+0:15: +0:16
     let mut _0: ();                      // return place in scope 0 at $DIR/while_storage.rs:+0:24: +0:24
     let mut _2: bool;                    // in scope 0 at $DIR/while_storage.rs:+1:11: +1:22
-    let mut _3: bool;                    // in scope 0 at $DIR/while_storage.rs:+1:20: +1:21
-    let mut _4: bool;                    // in scope 0 at $DIR/while_storage.rs:+2:12: +2:23
-    let mut _5: bool;                    // in scope 0 at $DIR/while_storage.rs:+2:21: +2:22
+    let mut _3: bool;                    // in scope 0 at $DIR/while_storage.rs:+2:12: +2:23
 
     bb0: {
         goto -> bb1;                     // scope 0 at $DIR/while_storage.rs:+1:5: +5:6
@@ -14,41 +12,35 @@ fn while_loop(_1: bool) -> () {
 
     bb1: {
         StorageLive(_2);                 // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
-        StorageLive(_3);                 // scope 0 at $DIR/while_storage.rs:+1:20: +1:21
-        _3 = _1;                         // scope 0 at $DIR/while_storage.rs:+1:20: +1:21
-        _2 = get_bool(move _3) -> bb2;   // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
+        _2 = get_bool(_1) -> bb2;        // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
                                          // mir::Constant
                                          // + span: $DIR/while_storage.rs:10:11: 10:19
                                          // + literal: Const { ty: fn(bool) -> bool {get_bool}, val: Value(<ZST>) }
     }
 
     bb2: {
-        StorageDead(_3);                 // scope 0 at $DIR/while_storage.rs:+1:21: +1:22
         switchInt(move _2) -> [0: bb7, otherwise: bb3]; // scope 0 at $DIR/while_storage.rs:+1:11: +1:22
     }
 
     bb3: {
-        StorageLive(_4);                 // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
-        StorageLive(_5);                 // scope 0 at $DIR/while_storage.rs:+2:21: +2:22
-        _5 = _1;                         // scope 0 at $DIR/while_storage.rs:+2:21: +2:22
-        _4 = get_bool(move _5) -> bb4;   // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
+        StorageLive(_3);                 // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
+        _3 = get_bool(_1) -> bb4;        // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
                                          // mir::Constant
                                          // + span: $DIR/while_storage.rs:11:12: 11:20
                                          // + literal: Const { ty: fn(bool) -> bool {get_bool}, val: Value(<ZST>) }
     }
 
     bb4: {
-        StorageDead(_5);                 // scope 0 at $DIR/while_storage.rs:+2:22: +2:23
-        switchInt(move _4) -> [0: bb6, otherwise: bb5]; // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
+        switchInt(move _3) -> [0: bb6, otherwise: bb5]; // scope 0 at $DIR/while_storage.rs:+2:12: +2:23
     }
 
     bb5: {
-        StorageDead(_4);                 // scope 0 at $DIR/while_storage.rs:+4:9: +4:10
+        StorageDead(_3);                 // scope 0 at $DIR/while_storage.rs:+4:9: +4:10
         goto -> bb7;                     // scope 0 at no-location
     }
 
     bb6: {
-        StorageDead(_4);                 // scope 0 at $DIR/while_storage.rs:+4:9: +4:10
+        StorageDead(_3);                 // scope 0 at $DIR/while_storage.rs:+4:9: +4:10
         StorageDead(_2);                 // scope 0 at $DIR/while_storage.rs:+5:5: +5:6
         goto -> bb1;                     // scope 0 at $DIR/while_storage.rs:+1:5: +5:6
     }