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

[Tex Riddell via cfe-commits]

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@@ -564,9 +585,9 @@ struct BuiltinTypeMethodBuilder {
                                       OK_Ordinary);
   }
 
-  BuiltinTypeMethodBuilder &
-  callBuiltin(StringRef BuiltinName, ArrayRef<Expr *> CallParms,
-              bool AddResourceHandleAsFirstArg = true) {
+  template <typename... Ts>
+  BuiltinTypeMethodBuilder &callBuiltin(StringRef BuiltinName, Ts... ArgSpecs) {
+    SmallVector<Expr *> Args{convertPlaceholder(std::forward<Ts>(ArgSpecs))...};
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tex3d wrote:

Yes, `SmallVector` will have stack allocated storage.  Its size is derived from the initialization, which is dependent on the number of ArgSpecs.

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