diff options
| -rw-r--r-- | lib/CodeGen/SimpleRegisterCoalescing.cpp | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp index 7a8ea6f..e5286c2 100644 --- a/lib/CodeGen/SimpleRegisterCoalescing.cpp +++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp @@ -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_); } |