From e0a73ec0a982a4213f3de9860545d9bf2814593d Mon Sep 17 00:00:00 2001 From: Jakob Stoklund Olesen Date: Fri, 1 Oct 2010 23:52:25 +0000 Subject: [PATCH] When RemoveCopyByCommutingDef is creating additional identity copies, just use LiveInterval::MergeValueNumberInto instead of trying to extend LiveRanges and getting it wrong. This fixed PR8249 where a valno with a multi-segment live range was defined by an identity copy created by RemoveCopyByCommutingDef. Some of the live segments disappeared. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115385 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/CodeGen/LiveInterval.h | 5 +++ lib/CodeGen/LiveInterval.cpp | 3 ++ lib/CodeGen/SimpleRegisterCoalescing.cpp | 54 +++--------------------- 3 files changed, 15 insertions(+), 47 deletions(-) diff --git a/include/llvm/CodeGen/LiveInterval.h b/include/llvm/CodeGen/LiveInterval.h index 706d4495169..720fb830e47 100644 --- a/include/llvm/CodeGen/LiveInterval.h +++ b/include/llvm/CodeGen/LiveInterval.h @@ -81,6 +81,11 @@ namespace llvm { unsigned getFlags() const { return flags; } void setFlags(unsigned flags) { this->flags = flags; } + /// Merge flags from another VNInfo + void mergeFlags(const VNInfo *VNI) { + flags = (flags | VNI->flags) & ~IS_UNUSED; + } + /// For a register interval, if this VN was definied by a copy instr /// getCopy() returns a pointer to it, otherwise returns 0. /// For a stack interval the behaviour of this method is undefined. diff --git a/lib/CodeGen/LiveInterval.cpp b/lib/CodeGen/LiveInterval.cpp index b4f0a94e97f..e18d7c7858b 100644 --- a/lib/CodeGen/LiveInterval.cpp +++ b/lib/CodeGen/LiveInterval.cpp @@ -582,6 +582,9 @@ VNInfo* LiveInterval::MergeValueNumberInto(VNInfo *V1, VNInfo *V2) { } } + // Merge the relevant flags. + V2->mergeFlags(V1); + // Now that V1 is dead, remove it. markValNoForDeletion(V1); diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp index 5a831750093..68ed3b103d6 100644 --- a/lib/CodeGen/SimpleRegisterCoalescing.cpp +++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp @@ -423,10 +423,6 @@ bool SimpleRegisterCoalescing::RemoveCopyByCommutingDef(const CoalescerPair &CP, unsigned OpIdx = NewMI->findRegisterUseOperandIdx(IntA.reg, false); NewMI->getOperand(OpIdx).setIsKill(); - bool BHasPHIKill = BValNo->hasPHIKill(); - SmallVector BDeadValNos; - std::map BExtend; - // If ALR and BLR overlaps and end of BLR extends beyond end of ALR, e.g. // A = or A, B // ... @@ -435,9 +431,6 @@ bool SimpleRegisterCoalescing::RemoveCopyByCommutingDef(const CoalescerPair &CP, // C = A // ... // = B - bool Extended = BLR->end > ALR->end && ALR->end != ALR->start; - if (Extended) - BExtend[ALR->end] = BLR->end; // Update uses of IntA of the specific Val# with IntB. for (MachineRegisterInfo::use_iterator UI = mri_->use_begin(IntA.reg), @@ -463,51 +456,24 @@ bool SimpleRegisterCoalescing::RemoveCopyByCommutingDef(const CoalescerPair &CP, UseMO.setReg(NewReg); if (UseMI == CopyMI) continue; - if (UseMO.isKill()) { - if (Extended) - UseMO.setIsKill(false); - } if (!UseMI->isCopy()) continue; if (UseMI->getOperand(0).getReg() != IntB.reg || UseMI->getOperand(0).getSubReg()) continue; - // This copy will become a noop. If it's defining a new val#, - // remove that val# as well. However this live range is being - // extended to the end of the existing live range defined by the copy. + // This copy will become a noop. If it's defining a new val#, merge it into + // BValNo. SlotIndex DefIdx = UseIdx.getDefIndex(); - const LiveRange *DLR = IntB.getLiveRangeContaining(DefIdx); - if (!DLR) + VNInfo *DVNI = IntB.getVNInfoAt(DefIdx); + if (!DVNI) continue; DEBUG(dbgs() << "\t\tnoop: " << DefIdx << '\t' << *UseMI); - BHasPHIKill |= DLR->valno->hasPHIKill(); - assert(DLR->valno->def == DefIdx); - BDeadValNos.push_back(DLR->valno); - BExtend[DLR->start] = DLR->end; + assert(DVNI->def == DefIdx); + BValNo = IntB.MergeValueNumberInto(BValNo, DVNI); JoinedCopies.insert(UseMI); } - // We need to insert a new liverange: [ALR.start, LastUse). It may be we can - // simply extend BLR if CopyMI doesn't end the range. - - // Remove val#'s defined by copies that will be coalesced away. - for (unsigned i = 0, e = BDeadValNos.size(); i != e; ++i) { - VNInfo *DeadVNI = BDeadValNos[i]; - if (TargetRegisterInfo::isPhysicalRegister(IntB.reg)) { - for (const unsigned *AS = tri_->getAliasSet(IntB.reg); *AS; ++AS) { - if (!li_->hasInterval(*AS)) - continue; - LiveInterval &ASLI = li_->getInterval(*AS); - if (const LiveRange *ASLR = ASLI.getLiveRangeContaining(DeadVNI->def)) - ASLI.removeValNo(ASLR->valno); - } - } - IntB.removeValNo(BDeadValNos[i]); - } - DEBUG(dbgs() << "\t\ttrimmed: " << IntB << '\n'); - - // Extend BValNo by merging in IntA live ranges of AValNo. Val# definition // is updated. VNInfo *ValNo = BValNo; @@ -516,14 +482,8 @@ bool SimpleRegisterCoalescing::RemoveCopyByCommutingDef(const CoalescerPair &CP, for (LiveInterval::iterator AI = IntA.begin(), AE = IntA.end(); AI != AE; ++AI) { if (AI->valno != AValNo) continue; - SlotIndex End = AI->end; - std::map::iterator - EI = BExtend.find(End); - if (EI != BExtend.end()) - End = EI->second; - IntB.addRange(LiveRange(AI->start, End, ValNo)); + IntB.addRange(LiveRange(AI->start, AI->end, ValNo)); } - ValNo->setHasPHIKill(BHasPHIKill); DEBUG(dbgs() << "\t\textended: " << IntB << '\n'); IntA.removeValNo(AValNo);