1 files changed, 34 insertions, 0 deletions
diff --git a/tests/codegen/mem-replace-simple-type.rs b/tests/codegen/mem-replace-simple-type.rs
new file mode 100644
index 000000000..4253ef136
--- /dev/null
+++ b/tests/codegen/mem-replace-simple-type.rs
@@ -0,0 +1,34 @@
+// compile-flags: -O -C no-prepopulate-passes
+// min-llvm-version: 15.0 (for opaque pointers)
+// only-x86_64 (to not worry about usize differing)
+// ignore-debug (the debug assertions get in the way)
+
+#![crate_type = "lib"]
+
+#[no_mangle]
+// CHECK-LABEL: @replace_usize(
+pub fn replace_usize(r: &mut usize, v: usize) -> usize {
+    // CHECK-NOT: alloca
+    // CHECK: %[[R:.+]] = load i64, ptr %r
+    // CHECK: store i64 %v, ptr %r
+    // CHECK: ret i64 %[[R]]
+    std::mem::replace(r, v)
+}
+
+#[no_mangle]
+// CHECK-LABEL: @replace_ref_str(
+pub fn replace_ref_str<'a>(r: &mut &'a str, v: &'a str) -> &'a str {
+    // CHECK-NOT: alloca
+    // CHECK: %[[A:.+]] = load ptr
+    // CHECK: %[[B:.+]] = load i64
+    // CHECK-NOT: store
+    // CHECK-NOT: load
+    // CHECK: store ptr
+    // CHECK: store i64
+    // CHECK-NOT: load
+    // CHECK-NOT: store
+    // CHECK: %[[P1:.+]] = insertvalue { ptr, i64 } poison, ptr %[[A]], 0
+    // CHECK: %[[P2:.+]] = insertvalue { ptr, i64 } %[[P1]], i64 %[[B]], 1
+    // CHECK: ret { ptr, i64 } %[[P2]]
+    std::mem::replace(r, v)
+}