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

[Nathan Gauër via cfe-commits]

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@@ -118,6 +118,48 @@ static void fixSeparateAttrArgAndNumber(StringRef ArgStr, SourceLocation ArgLoc,
   Slot = new (Ctx) IdentifierLoc(ArgLoc, PP.getIdentifierInfo(FixedArg));
 }
 
+Parser::ParsedSemantic Parser::ParseHLSLSemantic() {
+  assert(Tok.is(tok::identifier) && "Not a HLSL Annotation");
+
+  // Semantic pattern: [A-Za-z_]+[0-9]*
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Keenuts wrote:

Ah right, it's slightly more complex than what I hoped. Changed the regex.

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