[clang] [HLSL] Rework semantic handling as attributes (PR #166796)

[Steven Perron via cfe-commits]

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@@ -146,22 +146,26 @@ class CGHLSLRuntime {
 
   llvm::Value *emitSystemSemanticLoad(llvm::IRBuilder<> &B, llvm::Type *Type,
                                       const clang::DeclaratorDecl *Decl,
-                                      Attr *Semantic,
+                                      HLSLSemanticBaseAttr *Semantic,
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s-perron wrote:

Why use the base? Shouldn't this only be needed for an applied semantic? 

https://github.com/llvm/llvm-project/pull/166796