Avoid a bug in the path count computation, preventing an infinite

loop repeatedlt making the same change. This is for rdar://11256239.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155160 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2012-04-19 21:50:46 +00:00
parent c8969fd291
commit 8b74e5afda
2 changed files with 49 additions and 1 deletions

View File

@ -3379,7 +3379,7 @@ ObjCARCOpt::PerformCodePlacement(DenseMap<const BasicBlock *, BBState>
// Ok, everything checks out and we're all set. Let's move some code! // Ok, everything checks out and we're all set. Let's move some code!
Changed = true; Changed = true;
AnyPairsCompletelyEliminated = NewCount == 0; AnyPairsCompletelyEliminated = OldCount != 0 && NewCount == 0;
NumRRs += OldCount - NewCount; NumRRs += OldCount - NewCount;
MoveCalls(Arg, RetainsToMove, ReleasesToMove, MoveCalls(Arg, RetainsToMove, ReleasesToMove,
Retains, Releases, DeadInsts, M); Retains, Releases, DeadInsts, M);

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@ -0,0 +1,48 @@
; RUN: opt -S -objc-arc < %s | FileCheck %s
; Handle a retain+release pair entirely contained within a split loop backedge.
; rdar://11256239
; CHECK: define void @test0
; CHECK: call i8* @objc_retain(i8* %call) nounwind
; CHECK: call i8* @objc_retain(i8* %call) nounwind
; CHECK: call i8* @objc_retain(i8* %cond) nounwind
; CHECK: call void @objc_release(i8* %call) nounwind
; CHECK: call void @objc_release(i8* %call) nounwind
; CHECK: call void @objc_release(i8* %cond) nounwind
define void @test0() {
entry:
br label %while.body
while.body: ; preds = %while.cond
%call = invoke i8* @returner()
to label %invoke.cont unwind label %lpad, !clang.arc.no_objc_arc_exceptions !0
invoke.cont: ; preds = %while.body
%t0 = call i8* @objc_retain(i8* %call) nounwind
%t1 = call i8* @objc_retain(i8* %call) nounwind
%call.i1 = invoke i8* @returner()
to label %invoke.cont1 unwind label %lpad
invoke.cont1: ; preds = %invoke.cont
%cond = select i1 undef, i8* null, i8* %call
%t2 = call i8* @objc_retain(i8* %cond) nounwind
call void @objc_release(i8* %call) nounwind
call void @objc_release(i8* %call) nounwind
call void @use_pointer(i8* %cond)
call void @objc_release(i8* %cond) nounwind
br label %while.body
lpad: ; preds = %invoke.cont, %while.body
%t4 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__objc_personality_v0 to i8*)
catch i8* null
ret void
}
declare i8* @returner()
declare i32 @__objc_personality_v0(...)
declare void @objc_release(i8*)
declare i8* @objc_retain(i8*)
declare void @use_pointer(i8*)
!0 = metadata !{}