Revert "[ObjC][ARC] Don't remove autoreleaseRV/retainRV pairs if the call isn't"

This reverts commit 1f5b471b8b.
Causes asserts when building code with arc. See
https://bugs.chromium.org/p/chromium/issues/detail?id=1061289#c2
for a full repro. Will post a creduced repro once creduce is done
running.
This commit is contained in:
Nico Weber 2020-03-13 10:06:29 -04:00
parent 73d8a324ec
commit 86eb2c3991
2 changed files with 2 additions and 23 deletions

View File

@ -2296,7 +2296,7 @@ FindPredecessorAutoreleaseWithSafePath(const Value *Arg, BasicBlock *BB,
/// Look for this pattern:
/// \code
/// %call = tail call i8* @something(...)
/// %call = call i8* @something(...)
/// %2 = call i8* @objc_retain(i8* %call)
/// %3 = call i8* @objc_autorelease(i8* %2)
/// ret i8* %3
@ -2344,13 +2344,6 @@ void ObjCARCOpt::OptimizeReturns(Function &F) {
bool HasSafePathToCall = HasSafePathToPredecessorCall(Arg, Retain,
DependingInstructions,
Visited, PA);
// Don't remove retainRV/autoreleaseRV pairs if the call isn't a tail call.
if (GetBasicARCInstKind(Retain) == ARCInstKind::RetainRV &&
GetBasicARCInstKind(Autorelease) == ARCInstKind::AutoreleaseRV &&
!cast<CallInst>(*DependingInstructions.begin())->isTailCall())
continue;
DependingInstructions.clear();
Visited.clear();

View File

@ -77,7 +77,7 @@ define void @test2() {
; CHECK-NEXT: ret i8* %call
define i8* @test3() {
entry:
%call = tail call i8* @returner()
%call = call i8* @returner()
%0 = call i8* @llvm.objc.retainAutoreleasedReturnValue(i8* %call) nounwind
%1 = call i8* @llvm.objc.autoreleaseReturnValue(i8* %0) nounwind
ret i8* %1
@ -387,20 +387,6 @@ bb3:
ret i32* %retval
}
; Don't eliminate the retainRV/autoreleaseRV pair if the call isn't a tail call.
; CHECK-LABEL: define i8* @test28(
; CHECK: call i8* @returner()
; CHECK: call i8* @llvm.objc.retainAutoreleasedReturnValue(
; CHECK: call i8* @llvm.objc.autoreleaseReturnValue(
define i8* @test28() {
entry:
%call = call i8* @returner()
%0 = call i8* @llvm.objc.retainAutoreleasedReturnValue(i8* %call) nounwind
%1 = call i8* @llvm.objc.autoreleaseReturnValue(i8* %0) nounwind
ret i8* %1
}
!0 = !{}
; CHECK: attributes [[NUW]] = { nounwind }