Fix another case ShortenDeadCopySrcLiveRange is shortening too much. No test case possible since I don't know what to grep for. :-(

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64125 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2009-02-09 08:37:45 +00:00
parent dc54d317e7
commit 190424edcd

View File

@ -861,22 +861,29 @@ SimpleRegisterCoalescing::ShortenDeadCopySrcLiveRange(LiveInterval &li,
// If there is a last use in the same bb, we can't remove the live range.
// Shorten the live interval and return.
if (TrimLiveIntervalToLastUse(CopyIdx, CopyMI->getParent(), li, LR))
MachineBasicBlock *CopyMBB = CopyMI->getParent();
if (TrimLiveIntervalToLastUse(CopyIdx, CopyMBB, li, LR))
return false;
MachineBasicBlock *StartMBB = li_->getMBBFromIndex(RemoveStart);
if (!isSameOrFallThroughBB(StartMBB, CopyMBB, tii_))
// If the live range starts in another mbb and the copy mbb is not a fall
// through mbb, then we can only cut the range from the beginning of the
// copy mbb.
RemoveStart = li_->getMBBStartIdx(CopyMBB) + 1;
if (LR->valno->def == RemoveStart) {
// If the def MI defines the val# and this copy is the only kill of the
// val#, then propagate the dead marker.
if (!li.isOnlyLROfValNo(LR)) {
if (li.isKill(LR->valno, RemoveEnd))
li.removeKill(LR->valno, RemoveEnd);
} else {
if (li.isOnlyLROfValNo(LR)) {
PropagateDeadness(li, CopyMI, RemoveStart, li_, tri_);
++numDeadValNo;
}
if (li.isKill(LR->valno, RemoveEnd))
li.removeKill(LR->valno, RemoveEnd);
}
removeRange(li, RemoveStart, LR->end, li_, tri_);
removeRange(li, RemoveStart, RemoveEnd, li_, tri_);
return removeIntervalIfEmpty(li, li_, tri_);
}