[clang] [HLSL] Remove support for constructors for user defined structs (PR #190089)

[Helena Kotas via cfe-commits]

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@@ -153,10 +163,14 @@ TwoInts case5(int2 TwoVals) {
 // Case 6: Initialization from a scalarized structure of different type with
 // different element types.
 // CHECK-LABEL: define hidden void @_Z5case69TwoFloats(
-// CHECK-SAME: ptr dead_on_unwind noalias writable sret([[STRUCT_TWOINTS:%.*]]) align 1 [[AGG_RESULT:%.*]], ptr noundef byval([[STRUCT_TWOFLOATS:%.*]]) align 1 [[TF4:%.*]]) #[[ATTR0]] {
+// CHECK-SAME: ptr dead_on_unwind noalias writable sret([[STRUCT_TWOINTS:%.*]]) align 1 [[AGG_RESULT:%.*]], ptr noundef dead_on_return [[TF4:%.*]]) #[[ATTR0]] {
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hekota wrote:

That because we treat struct and classes as packed by default: https://github.com/llvm/llvm-project/pull/137391

https://github.com/llvm/llvm-project/pull/190089