[clang] [HLSL] Forward arguments in BuiltinTypeMethodBuilder::callBuiltin. NFC (PR #117789)

[Helena Kotas via cfe-commits]

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@@ -502,7 +520,10 @@ struct BuiltinTypeMethodBuilder {
                                      HLSLParamModifierAttr::Spelling Modifier =
                                          HLSLParamModifierAttr::Keyword_in) {
     assert(Method == nullptr && "Cannot add param, method already created");
-    llvm_unreachable("not yet implemented");
+    const IdentifierInfo &II = DeclBuilder.SemaRef.getASTContext().Idents.get(
+        Name, tok::TokenKind::identifier);
+    Params.emplace_back(II, Ty, Modifier);
+    return *this;
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hekota wrote:

I did not include this in my previous PR because it cannot be tested yet.

https://github.com/llvm/llvm-project/pull/117789