diff options
Diffstat (limited to 'llvm/lib/CodeGen')
| -rw-r--r-- | llvm/lib/CodeGen/RegisterCoalescer.cpp | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/llvm/lib/CodeGen/RegisterCoalescer.cpp b/llvm/lib/CodeGen/RegisterCoalescer.cpp index ca53fe4f393..58e29d613f0 100644 --- a/llvm/lib/CodeGen/RegisterCoalescer.cpp +++ b/llvm/lib/CodeGen/RegisterCoalescer.cpp @@ -3032,7 +3032,9 @@ void JoinVals::pruneSubRegValues(LiveInterval &LI, LaneBitmask &ShrinkMask) { // If a subrange starts at the copy then an undefined value has been // copied and we must remove that subrange value as well. VNInfo *ValueOut = Q.valueOutOrDead(); - if (ValueOut != nullptr && Q.valueIn() == nullptr) { + if (ValueOut != nullptr && (Q.valueIn() == nullptr || + (V.Identical && V.Resolution == CR_Erase && + ValueOut->def == Def))) { LLVM_DEBUG(dbgs() << "\t\tPrune sublane " << PrintLaneMask(S.LaneMask) << " at " << Def << "\n"); SmallVector<SlotIndex,8> EndPoints; @@ -3041,7 +3043,7 @@ void JoinVals::pruneSubRegValues(LiveInterval &LI, LaneBitmask &ShrinkMask) { // Mark value number as unused. ValueOut->markUnused(); - if (V.Identical && S.Query(OtherDef).valueOut()) { + if (V.Identical && S.Query(OtherDef).valueOutOrDead()) { // If V is identical to V.OtherVNI (and S was live at OtherDef), // then we can't simply prune V from S. V needs to be replaced // with V.OtherVNI. |
