[CodeGen][ObjC] Fix assert on calling `__builtin_constant_p` with ObjC objects.
When we are calling `__builtin_constant_p` with ObjC objects of
different classes, we hit the assertion
> Assertion failed: (isa<X>(Val) && "cast<Ty>() argument of incompatible type!"), function cast, file include/llvm/Support/Casting.h, line 254.
It happens because LLVM types for `ObjCInterfaceType` are opaque and
have no name (see `CodeGenTypes::ConvertType`). As the result, for
different ObjC classes we have different `is_constant` intrinsics with
the same name `llvm.is.constant.p0s_s`. When we try to reuse an
intrinsic with the same name, we fail because of type mismatch.
Fix by bitcasting `ObjCObjectPointerType` to `id` prior to passing as an
argument to `__builtin_constant_p`. This results in using intrinsic
`llvm.is.constant.p0i8` and correct types.
rdar://problem/47499250
Reviewers: rjmccall, ahatanak, void
Reviewed By: void, ahatanak
Subscribers: ddunbar, jkorous, hans, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D57427
llvm-svn: 353577
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 68d2731..5448ac1 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -1982,6 +1982,12 @@
return RValue::get(ConstantInt::get(ResultType, 0));
Value *ArgValue = EmitScalarExpr(Arg);
+ if (ArgType->isObjCObjectPointerType()) {
+ // Convert Objective-C objects to id because we cannot distinguish between
+ // LLVM types for Obj-C classes as they are opaque.
+ ArgType = CGM.getContext().getObjCIdType();
+ ArgValue = Builder.CreateBitCast(ArgValue, ConvertType(ArgType));
+ }
Function *F =
CGM.getIntrinsic(Intrinsic::is_constant, ConvertType(ArgType));
Value *Result = Builder.CreateCall(F, ArgValue);