Add a codegen test for transparent aggregates

Author: scottmcm

tests/codegen/transparent-aggregates.rs

@@ -0,0 +1,29 @@
+//@ compile-flags: -O -C no-prepopulate-passes
+
+#![crate_type = "lib"]
+
+#[repr(transparent)]
+struct Transparent32(u32);
+
+// CHECK: i32 @make_transparent(i32 noundef %x)
+#[no_mangle]
+pub fn make_transparent(x: u32) -> Transparent32 {
+    // CHECK: %a = alloca i32
+    // CHECK: store i32 %x, ptr %a
+    // CHECK: %[[TEMP:.+]] = load i32, ptr %a
+    // CHECK: ret i32 %[[TEMP]]
+    let a = Transparent32(x);
+    a
+}
+
+// CHECK-LABEL: { i32, i32 } @make_2_tuple(i32 noundef %x)
+#[no_mangle]
+pub fn make_2_tuple(x: u32) -> (u32, u32) {
+    // CHECK: %pair = alloca { i32, i32 }
+    // CHECK: store i32
+    // CHECK: store i32
+    // CHECK: load i32
+    // CHECK: load i32
+    let pair = (x, x);
+    pair
+}