From bd63520161629385ff5a0b037eccc770d8d15289 Mon Sep 17 00:00:00 2001 From: Dale Johannesen Date: Wed, 10 Feb 2010 00:55:42 +0000 Subject: [PATCH] Skip DBG_VALUE many places in live intervals and register coalescing. This fixes many crashes and places where debug info affects codegen (when dbg.value is lowered to machine instructions, which it isn't yet in TOT). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95739 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/LiveIntervalAnalysis.cpp | 52 ++++++++++++++---------- lib/CodeGen/SimpleRegisterCoalescing.cpp | 43 ++++++++++++-------- 2 files changed, 57 insertions(+), 38 deletions(-) diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp index 27e56202383..efc050e061b 100644 --- a/lib/CodeGen/LiveIntervalAnalysis.cpp +++ b/lib/CodeGen/LiveIntervalAnalysis.cpp @@ -512,6 +512,8 @@ void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock *MBB, baseIndex = baseIndex.getNextIndex(); while (++mi != MBB->end()) { + if (mi->isDebugValue()) + continue; if (getInstructionFromIndex(baseIndex) == 0) baseIndex = indexes_->getNextNonNullIndex(baseIndex); @@ -527,8 +529,8 @@ void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock *MBB, end = baseIndex.getDefIndex(); } else { // Another instruction redefines the register before it is ever read. - // Then the register is essentially dead at the instruction that defines - // it. Hence its interval is: + // Then the register is essentially dead at the instruction that + // defines it. Hence its interval is: // [defSlot(def), defSlot(def)+1) DEBUG(dbgs() << " dead"); end = start.getStoreIndex(); @@ -606,26 +608,28 @@ void LiveIntervals::handleLiveInRegister(MachineBasicBlock *MBB, SlotIndex end = baseIndex; bool SeenDefUse = false; - - while (mi != MBB->end()) { - if (mi->killsRegister(interval.reg, tri_)) { - DEBUG(dbgs() << " killed"); - end = baseIndex.getDefIndex(); - SeenDefUse = true; - break; - } else if (mi->modifiesRegister(interval.reg, tri_)) { - // Another instruction redefines the register before it is ever read. - // Then the register is essentially dead at the instruction that defines - // it. Hence its interval is: - // [defSlot(def), defSlot(def)+1) - DEBUG(dbgs() << " dead"); - end = start.getStoreIndex(); - SeenDefUse = true; - break; - } + MachineBasicBlock::iterator E = MBB->end(); + while (mi != E) { + if (!mi->isDebugValue()) { + if (mi->killsRegister(interval.reg, tri_)) { + DEBUG(dbgs() << " killed"); + end = baseIndex.getDefIndex(); + SeenDefUse = true; + break; + } else if (mi->modifiesRegister(interval.reg, tri_)) { + // Another instruction redefines the register before it is ever read. + // Then the register is essentially dead at the instruction that defines + // it. Hence its interval is: + // [defSlot(def), defSlot(def)+1) + DEBUG(dbgs() << " dead"); + end = start.getStoreIndex(); + SeenDefUse = true; + break; + } + } ++mi; - if (mi != MBB->end()) { + if (mi != E && !mi->isDebugValue()) { baseIndex = indexes_->getNextNonNullIndex(baseIndex); } } @@ -1056,7 +1060,7 @@ rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI, // If this is the rematerializable definition MI itself and // all of its uses are rematerialized, simply delete it. if (MI == ReMatOrigDefMI && CanDelete) { - DEBUG(dbgs() << "\t\t\t\tErasing re-materlizable def: " + DEBUG(dbgs() << "\t\t\t\tErasing re-materializable def: " << MI << '\n'); RemoveMachineInstrFromMaps(MI); vrm.RemoveMachineInstrFromMaps(MI); @@ -1299,6 +1303,12 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, MachineInstr *MI = &*ri; MachineOperand &O = ri.getOperand(); ++ri; + if (MI->isDebugValue()) { + // Remove debug info for now. + O.setReg(0U); + DEBUG(dbgs() << "Removing debug info due to spill:" << "\t" << *MI); + continue; + } assert(!O.isImplicit() && "Spilling register that's used as implicit use?"); SlotIndex index = getInstructionIndex(MI); if (index < start || index >= end) diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp index c33f6b37fe0..1faa5a094a4 100644 --- a/lib/CodeGen/SimpleRegisterCoalescing.cpp +++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp @@ -375,8 +375,9 @@ bool SimpleRegisterCoalescing::RemoveCopyByCommutingDef(LiveInterval &IntA, // If some of the uses of IntA.reg is already coalesced away, return false. // It's not possible to determine whether it's safe to perform the coalescing. - for (MachineRegisterInfo::use_iterator UI = mri_->use_begin(IntA.reg), - UE = mri_->use_end(); UI != UE; ++UI) { + for (MachineRegisterInfo::use_nodbg_iterator UI = + mri_->use_nodbg_begin(IntA.reg), + UE = mri_->use_nodbg_end(); UI != UE; ++UI) { MachineInstr *UseMI = &*UI; SlotIndex UseIdx = li_->getInstructionIndex(UseMI); LiveInterval::iterator ULR = IntA.FindLiveRangeContaining(UseIdx); @@ -430,6 +431,12 @@ bool SimpleRegisterCoalescing::RemoveCopyByCommutingDef(LiveInterval &IntA, ++UI; if (JoinedCopies.count(UseMI)) continue; + if (UseMI->isDebugValue()) { + // FIXME These don't have an instruction index. Not clear we have enough + // info to decide whether to do this replacement or not. For now do it. + UseMO.setReg(NewReg); + continue; + } SlotIndex UseIdx = li_->getInstructionIndex(UseMI).getUseIndex(); LiveInterval::iterator ULR = IntA.FindLiveRangeContaining(UseIdx); if (ULR == IntA.end() || ULR->valno != AValNo) @@ -1029,8 +1036,9 @@ SimpleRegisterCoalescing::isWinToJoinVRWithSrcPhysReg(MachineInstr *CopyMI, unsigned Threshold = allocatableRCRegs_[RC].count() * 2; unsigned Length = li_->getApproximateInstructionCount(DstInt); if (Length > Threshold && - (((float)std::distance(mri_->use_begin(DstInt.reg), - mri_->use_end()) / Length) < (1.0 / Threshold))) + (((float)std::distance(mri_->use_nodbg_begin(DstInt.reg), + mri_->use_nodbg_end()) / Length) < + (1.0 / Threshold))) return false; // If the virtual register live interval extends into a loop, turn down @@ -1079,15 +1087,16 @@ SimpleRegisterCoalescing::isWinToJoinVRWithDstPhysReg(MachineInstr *CopyMI, MachineBasicBlock *CopyMBB, LiveInterval &DstInt, LiveInterval &SrcInt) { - // If the virtual register live interval is long but it has low use desity, + // If the virtual register live interval is long but it has low use density, // do not join them, instead mark the physical register as its allocation // preference. const TargetRegisterClass *RC = mri_->getRegClass(SrcInt.reg); unsigned Threshold = allocatableRCRegs_[RC].count() * 2; unsigned Length = li_->getApproximateInstructionCount(SrcInt); if (Length > Threshold && - (((float)std::distance(mri_->use_begin(SrcInt.reg), - mri_->use_end()) / Length) < (1.0 / Threshold))) + (((float)std::distance(mri_->use_nodbg_begin(SrcInt.reg), + mri_->use_nodbg_end()) / Length) < + (1.0 / Threshold))) return false; if (SrcInt.empty()) @@ -1140,10 +1149,10 @@ SimpleRegisterCoalescing::isWinToJoinCrossClass(unsigned LargeReg, unsigned LargeSize = li_->getApproximateInstructionCount(LargeInt); unsigned SmallSize = li_->getApproximateInstructionCount(SmallInt); if (SmallSize > Threshold || LargeSize > Threshold) - if ((float)std::distance(mri_->use_begin(SmallReg), - mri_->use_end()) / SmallSize < - (float)std::distance(mri_->use_begin(LargeReg), - mri_->use_end()) / LargeSize) + if ((float)std::distance(mri_->use_nodbg_begin(SmallReg), + mri_->use_nodbg_end()) / SmallSize < + (float)std::distance(mri_->use_nodbg_begin(LargeReg), + mri_->use_nodbg_end()) / LargeSize) return false; return true; } @@ -1630,8 +1639,8 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) { unsigned Length = li_->getApproximateInstructionCount(JoinVInt); float Ratio = 1.0 / Threshold; if (Length > Threshold && - (((float)std::distance(mri_->use_begin(JoinVReg), - mri_->use_end()) / Length) < Ratio)) { + (((float)std::distance(mri_->use_nodbg_begin(JoinVReg), + mri_->use_nodbg_end()) / Length) < Ratio)) { mri_->setRegAllocationHint(JoinVInt.reg, 0, JoinPReg); ++numAborts; DEBUG(dbgs() << "\tMay tie down a physical register, abort!\n"); @@ -2564,8 +2573,8 @@ SimpleRegisterCoalescing::differingRegisterClasses(unsigned RegA, return !RegClassA->contains(RegB); } -/// lastRegisterUse - Returns the last use of the specific register between -/// cycles Start and End or NULL if there are no uses. +/// lastRegisterUse - Returns the last (non-debug) use of the specific register +/// between cycles Start and End or NULL if there are no uses. MachineOperand * SimpleRegisterCoalescing::lastRegisterUse(SlotIndex Start, SlotIndex End, @@ -2574,8 +2583,8 @@ SimpleRegisterCoalescing::lastRegisterUse(SlotIndex Start, UseIdx = SlotIndex(); if (TargetRegisterInfo::isVirtualRegister(Reg)) { MachineOperand *LastUse = NULL; - for (MachineRegisterInfo::use_iterator I = mri_->use_begin(Reg), - E = mri_->use_end(); I != E; ++I) { + for (MachineRegisterInfo::use_nodbg_iterator I = mri_->use_nodbg_begin(Reg), + E = mri_->use_nodbg_end(); I != E; ++I) { MachineOperand &Use = I.getOperand(); MachineInstr *UseMI = Use.getParent(); unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx; -- 2.34.1