[clang] [libcxx] [Clang] Add __builtin_invoke and use it in libc++ (PR #116709)

[Erich Keane via cfe-commits]

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@@ -5406,6 +5408,101 @@ ExprResult Sema::ConvertVectorExpr(Expr *E, TypeSourceInfo *TInfo,
                                    RParenLoc, CurFPFeatureOverrides());
 }
 
+ExprResult Sema::BuiltinInvoke(CallExpr *TheCall) {
+  auto Loc = TheCall->getBeginLoc();
+  auto Args = MutableArrayRef(TheCall->getArgs(), TheCall->getNumArgs());
+  assert(llvm::none_of(Args,
+                       [](Expr *Arg) { return Arg->isTypeDependent(); }));
+
+  if (Args.size() == 0) {
+    Diag(TheCall->getBeginLoc(), diag::err_typecheck_call_too_few_args_at_least)
+        << 0 << 1 << 0 << 0 << TheCall->getSourceRange();
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erichkeane wrote:

These 4 need some sort of comments showing what they mean.

https://github.com/llvm/llvm-project/pull/116709