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

[Helena Kotas via cfe-commits]

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@@ -976,17 +977,21 @@ void CGHLSLRuntime::emitEntryFunction(const FunctionDecl *FD,
             PD->getAttr<HLSLParamModifierAttr>()) {
       llvm_unreachable("Not handled yet");
     } else {
-      llvm::Type *ParamType =
-          Param.hasByValAttr() ? Param.getParamByValType() : Param.getType();
+      llvm::Type *ParamType = Param.hasByValAttr() ? Param.getParamByValType()
+                              : PD->getType()->isRecordType()
+                                  ? CGM.getTypes().ConvertType(PD->getType())
+                                  : Param.getType();
       auto AttrBegin = PD->specific_attr_begin<HLSLAppliedSemanticAttr>();
       auto AttrEnd = PD->specific_attr_end<HLSLAppliedSemanticAttr>();
       auto Result =
           handleSemanticLoad(B, FD, ParamType, PD, AttrBegin, AttrEnd);
       SemanticValue = Result.first;
       if (!SemanticValue)
         return;
-      if (Param.hasByValAttr()) {
-        llvm::Value *Var = B.CreateAlloca(Param.getParamByValType());
+      // if this is a ptr to a record and it does'nt have byval attr
+      // we still need the record type not just 'ptr'
----------------
hekota wrote:

Nit - typo, and all comments should be full sentences. Applies to other comments in this PR as well.
```suggestion
      // If this is a 'ptr' to a record and it doesn't have byval attribute,
      // we still need the record type, not just 'ptr'.
```

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