[clang] [HLSL] Rewrite semantics parsing (PR #152537)

[Nathan Gauër via cfe-commits]

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@@ -282,14 +327,17 @@ void Parser::ParseHLSLAnnotations(ParsedAttributes &Attrs,
       return;
     }
   } break;
-  case ParsedAttr::UnknownAttribute:
-    Diag(Loc, diag::err_unknown_hlsl_semantic) << II;
-    return;
-  case ParsedAttr::AT_HLSLSV_GroupThreadID:
-  case ParsedAttr::AT_HLSLSV_GroupID:
-  case ParsedAttr::AT_HLSLSV_GroupIndex:
-  case ParsedAttr::AT_HLSLSV_DispatchThreadID:
-  case ParsedAttr::AT_HLSLSV_Position:
+  case ParsedAttr::AT_HLSLUnparsedSemantic: {
+    ASTContext &Ctx = Actions.getASTContext();
+    ArgExprs.push_back(IntegerLiteral::Create(
+        Ctx, llvm::APInt(Ctx.getTypeSize(Ctx.IntTy), Semantic.Index), Ctx.IntTy,
+        SourceLocation()));
+    ArgExprs.push_back(IntegerLiteral::Create(
+        Ctx, llvm::APInt(1, Semantic.Explicit), Ctx.BoolTy, SourceLocation()));
+    II = PP.getIdentifierInfo(Semantic.Name.upper());
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Keenuts wrote:

Make sense, especially with the macro bit. Remove the `upper()` call and modify the code to make it work without. Also added a test case for the macro sample you shared.

https://github.com/llvm/llvm-project/pull/152537