1 files changed, 88 insertions, 0 deletions
diff --git a/tests/mir-opt/sroa.rs b/tests/mir-opt/sroa.rs
new file mode 100644
index 000000000..ff8deb40d
--- /dev/null
+++ b/tests/mir-opt/sroa.rs
@@ -0,0 +1,88 @@
+// unit-test: ScalarReplacementOfAggregates
+// compile-flags: -Cpanic=abort
+// no-prefer-dynamic
+
+struct Tag(usize);
+
+#[repr(C)]
+struct S(Tag, Tag, Tag);
+
+impl Drop for Tag {
+    #[inline(never)]
+    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,
+        a: f32,
+    }
+
+    U { _foo: 0, a }.a
+}
+
+// EMIT_MIR sroa.unions.ScalarReplacementOfAggregates.diff
+pub fn unions(a: f32) -> u32 {
+    union Repr {
+        f: f32,
+        u: u32,
+    }
+    unsafe { Repr { f: a }.u }
+}
+
+struct Foo {
+    a: u8,
+    b: (),
+    c: &'static str,
+    d: Option<isize>,
+}
+
+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;
+    let _ = b;
+    let _ = c;
+    let _ = d;
+}
+
+#[repr(C)]
+struct Escaping {
+    a: u32,
+    b: u32,
+    c: u32,
+}
+
+fn f(a: *const u32) {
+    println!("{}", unsafe { *a.add(2) });
+}
+
+// EMIT_MIR sroa.escaping.ScalarReplacementOfAggregates.diff
+pub fn escaping() {
+    // Verify this struct is not flattened.
+    f(&Escaping { a: 1, b: 2, c: g() }.a);
+}
+
+fn main() {
+    dropping();
+    enums(5);
+    structs(5.);
+    unions(5.);
+    flat();
+    escaping();
+}