[clang] [HLSL] Implement output parameter (PR #101083)

[Chris B via cfe-commits]

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@@ -8511,7 +8514,7 @@ static void HandleHLSLParamModifierAttr(QualType &CurType,
     return;
   if (Attr.getSemanticSpelling() == HLSLParamModifierAttr::Keyword_inout ||
       Attr.getSemanticSpelling() == HLSLParamModifierAttr::Keyword_out)
-    CurType = S.getASTContext().getLValueReferenceType(CurType);
+    CurType = S.HLSL().getInoutParameterType(CurType);
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llvm-beanz wrote:

HLSL doesn't allow references or pointers (at least not explicitly). We generate references in the AST in a few places, but any attempt to write or type-deduce one results in an error in Sema.

In theory, any legal type in HLSL can be converted to an inout parameter type.

https://github.com/llvm/llvm-project/pull/101083