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

[Damyan Pepper 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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damyanp wrote:

Is SmallVector smart enough for this to evaporate into being a stack allocated array, or is there a chance that it might make a heap allocation to store the args?

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