[clang] [clang] Add builtin_get_vtable_pointer and virtual_member_address (PR #135469)

[Oliver Hunt via cfe-commits]

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@@ -1782,6 +1782,92 @@ static ExprResult PointerAuthStringDiscriminator(Sema &S, CallExpr *Call) {
   return Call;
 }
 
+static ExprResult VirtualMemberAddress(Sema &S, CallExpr *Call) {
+  if (S.checkArgCount(Call, 2))
+    return ExprError();
+
+  for (int i = 0; i < 2; ++i) {
+    ExprResult ArgRValue =
+        S.DefaultFunctionArrayLvalueConversion(Call->getArg(1));
+    if (ArgRValue.isInvalid())
+      return ExprError();
+    Call->setArg(1, ArgRValue.get());
+  }
+
+  if (Call->getArg(0)->isTypeDependent() || Call->getArg(1)->isValueDependent())
+    return Call;
+
+  const Expr *ThisArg = Call->getArg(0);
+  QualType ThisTy = ThisArg->getType();
+  if (ThisTy->isPointerOrReferenceType())
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ojhunt wrote:

I'll update this to make it warn on a reference parameter

https://github.com/llvm/llvm-project/pull/135469