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

[via libcxx-commits]

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@@ -5406,6 +5408,99 @@ ExprResult Sema::ConvertVectorExpr(Expr *E, TypeSourceInfo *TInfo,
                                    RParenLoc, CurFPFeatureOverrides());
 }
 
+ExprResult Sema::BuiltinInvoke(CallExpr *TheCall) {
+  SourceLocation 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)
+        << /*callee_type=*/0 << /*min_arg_count=*/1 << /*actual_arg_count=*/0
+        << /*is_non_object=*/0 << TheCall->getSourceRange();
+    return ExprError();
+  }
+
+  auto FuncT = Args[0]->getType();
+
+  if (auto *MPT = FuncT->getAs<MemberPointerType>()) {
+    if (Args.size() < 2) {
+      Diag(TheCall->getBeginLoc(),
+           diag::err_typecheck_call_too_few_args_at_least)
+          << /*callee_type=*/0 << /*min_arg_count=*/2 << /*actual_arg_count=*/1
+          << /*is_non_object=*/0 << TheCall->getSourceRange();
+      return ExprError();
+    }
+
+    auto *MemPtrClass = MPT->getQualifier()->getAsType();
+    auto ObjectT = Args[1]->getType();
+
+    if (MPT->isMemberDataPointer() && checkArgCount(TheCall, 2))
+      return ExprError();
+
+    ExprResult ObjectArg = [&]() -> ExprResult {
+      // (1.1): (t1.*f)(t2, …, tN) when f is a pointer to a member function of a
+      // class T and is_same_v<T, remove_cvref_t<decltype(t1)>> ||
+      // is_base_of_v<T, remove_cvref_t<decltype(t1)>> is true;
+      // (1.4): t1.*f when N=1 and f is a pointer to data member of a class T
+      // and is_same_v<T, remove_cvref_t<decltype(t1)>> ||
+      // is_base_of_v<T, remove_cvref_t<decltype(t1)>> is true;
+      if (Context.hasSameType(QualType(MemPtrClass, 0),
+                              BuiltinRemoveCVRef(ObjectT, Loc)) ||
+          BuiltinIsBaseOf(Args[1]->getBeginLoc(), QualType(MemPtrClass, 0),
+                          BuiltinRemoveCVRef(ObjectT, Loc))) {
+        return Args[1];
+      }
+
+      // (t1.get().*f)(t2, …, tN) when f is a pointer to a member function of
+      // a class T and remove_cvref_t<decltype(t1)> is a specialization of
+      // reference_wrapper;
+      if (auto *RD = ObjectT->getAsCXXRecordDecl()) {
+        if (RD->isInStdNamespace() &&
+            RD->getDeclName().getAsString() == "reference_wrapper") {
+          CXXScopeSpec SS;
+          IdentifierInfo *GetName = &Context.Idents.get("get");
+          UnqualifiedId GetID;
+          GetID.setIdentifier(GetName, Loc);
+
+          auto MemExpr = ActOnMemberAccessExpr(
+              getCurScope(), Args[1], Loc, tok::period, SS,
+              /*TemplateKWLoc=*/SourceLocation(), GetID, nullptr);
+
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cor3ntin wrote:

Can you check that this SFINAE properly?

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