Fix an iterator invalidation problem. operator[] on a DenseMap

can insert a new element, invalidating iterators. Use find
instead, and handle the case where the key is not found explicitly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151871 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2012-03-02 01:26:46 +00:00
parent 22cc4ccc9e
commit 70e2968866

View File

@ -2421,12 +2421,22 @@ ObjCARCOpt::CheckForCFGHazards(const BasicBlock *BB,
--SE;
for (; SI != SE; ++SI) {
PtrState &SuccS = BBStates[*SI].getPtrBottomUpState(Arg);
switch (SuccS.GetSeq()) {
Sequence SuccSSeq = S_None;
bool SuccSRRIKnownSafe = false;
// If VisitBottomUp has visited this successor, take what we know about it.
DenseMap<const BasicBlock *, BBState>::iterator BBI = BBStates.find(*SI);
if (BBI != BBStates.end()) {
const PtrState &SuccS = BBI->second.getPtrBottomUpState(Arg);
SuccSSeq = SuccS.GetSeq();
SuccSRRIKnownSafe = SuccS.RRI.KnownSafe;
}
switch (SuccSSeq) {
case S_None:
case S_CanRelease: {
if (!S.RRI.KnownSafe && !SuccS.RRI.KnownSafe)
if (!S.RRI.KnownSafe && !SuccSRRIKnownSafe) {
S.ClearSequenceProgress();
break;
}
continue;
}
case S_Use:
@ -2435,7 +2445,7 @@ ObjCARCOpt::CheckForCFGHazards(const BasicBlock *BB,
case S_Stop:
case S_Release:
case S_MovableRelease:
if (!S.RRI.KnownSafe && !SuccS.RRI.KnownSafe)
if (!S.RRI.KnownSafe && !SuccSRRIKnownSafe)
AllSuccsHaveSame = false;
break;
case S_Retain:
@ -2464,11 +2474,21 @@ ObjCARCOpt::CheckForCFGHazards(const BasicBlock *BB,
--SE;
for (; SI != SE; ++SI) {
PtrState &SuccS = BBStates[*SI].getPtrBottomUpState(Arg);
switch (SuccS.GetSeq()) {
Sequence SuccSSeq = S_None;
bool SuccSRRIKnownSafe = false;
// If VisitBottomUp has visited this successor, take what we know about it.
DenseMap<const BasicBlock *, BBState>::iterator BBI = BBStates.find(*SI);
if (BBI != BBStates.end()) {
const PtrState &SuccS = BBI->second.getPtrBottomUpState(Arg);
SuccSSeq = SuccS.GetSeq();
SuccSRRIKnownSafe = SuccS.RRI.KnownSafe;
}
switch (SuccSSeq) {
case S_None: {
if (!S.RRI.KnownSafe && !SuccS.RRI.KnownSafe)
if (!S.RRI.KnownSafe && !SuccSRRIKnownSafe) {
S.ClearSequenceProgress();
break;
}
continue;
}
case S_CanRelease:
@ -2478,7 +2498,7 @@ ObjCARCOpt::CheckForCFGHazards(const BasicBlock *BB,
case S_Release:
case S_MovableRelease:
case S_Use:
if (!S.RRI.KnownSafe && !SuccS.RRI.KnownSafe)
if (!S.RRI.KnownSafe && !SuccSRRIKnownSafe)
AllSuccsHaveSame = false;
break;
case S_Retain: