X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=lib%2FCodeGen%2FLiveIntervalAnalysis.cpp;h=53366b9f0741349a6b3e3474f756a8c5223b9197;hp=b5c21952fa3da858ffd0a50714b8df3b8aeb156b;hb=01cb1b665da03e2b74c0724f71751e912ec8c2be;hpb=fb11288109329cb736d9f49769581a0d0c23fe19 diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp index b5c21952fa3..53366b9f074 100644 --- a/lib/CodeGen/LiveIntervalAnalysis.cpp +++ b/lib/CodeGen/LiveIntervalAnalysis.cpp @@ -23,19 +23,26 @@ #include "llvm/CodeGen/LiveVariables.h" #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineInstr.h" +#include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineLoopInfo.h" +#include "llvm/CodeGen/MachineMemOperand.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/Passes.h" -#include "llvm/CodeGen/PseudoSourceValue.h" +#include "llvm/CodeGen/ProcessImplicitDefs.h" #include "llvm/Target/TargetRegisterInfo.h" #include "llvm/Target/TargetInstrInfo.h" #include "llvm/Target/TargetMachine.h" #include "llvm/Target/TargetOptions.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/ADT/DepthFirstIterator.h" +#include "llvm/ADT/SmallSet.h" #include "llvm/ADT/Statistic.h" #include "llvm/ADT/STLExtras.h" #include +#include #include using namespace llvm; @@ -43,24 +50,18 @@ using namespace llvm; static cl::opt DisableReMat("disable-rematerialization", cl::init(false), cl::Hidden); -static cl::opt SplitAtBB("split-intervals-at-bb", - cl::init(true), cl::Hidden); -static cl::opt SplitLimit("split-limit", - cl::init(-1), cl::Hidden); - -static cl::opt EnableAggressiveRemat("aggressive-remat", cl::Hidden); - static cl::opt EnableFastSpilling("fast-spill", cl::init(false), cl::Hidden); -STATISTIC(numIntervals, "Number of original intervals"); -STATISTIC(numFolds , "Number of loads/stores folded into instructions"); -STATISTIC(numSplits , "Number of intervals split"); +STATISTIC(numIntervals , "Number of original intervals"); +STATISTIC(numFolds , "Number of loads/stores folded into instructions"); +STATISTIC(numSplits , "Number of intervals split"); char LiveIntervals::ID = 0; static RegisterPass X("liveintervals", "Live Interval Analysis"); void LiveIntervals::getAnalysisUsage(AnalysisUsage &AU) const { + AU.setPreservesCFG(); AU.addRequired(); AU.addPreserved(); AU.addPreserved(); @@ -74,175 +75,35 @@ void LiveIntervals::getAnalysisUsage(AnalysisUsage &AU) const { } AU.addRequiredID(TwoAddressInstructionPassID); + AU.addPreserved(); + AU.addRequired(); + AU.addPreserved(); + AU.addRequiredTransitive(); MachineFunctionPass::getAnalysisUsage(AU); } +static void VNInfoDTor(void* Ptr) +{ + reinterpret_cast(Ptr)->~VNInfo(); +} + void LiveIntervals::releaseMemory() { // Free the live intervals themselves. for (DenseMap::iterator I = r2iMap_.begin(), E = r2iMap_.end(); I != E; ++I) delete I->second; - MBB2IdxMap.clear(); - Idx2MBBMap.clear(); - mi2iMap_.clear(); - i2miMap_.clear(); r2iMap_.clear(); + // Release VNInfo memroy regions after all VNInfo objects are dtor'd. - VNInfoAllocator.Reset(); - while (!ClonedMIs.empty()) { - MachineInstr *MI = ClonedMIs.back(); - ClonedMIs.pop_back(); + VNInfoAllocator.Reset((unsigned)sizeof(VNInfo), alignof(), VNInfoDTor); + while (!CloneMIs.empty()) { + MachineInstr *MI = CloneMIs.back(); + CloneMIs.pop_back(); mf_->DeleteMachineInstr(MI); } } -void LiveIntervals::computeNumbering() { - Index2MiMap OldI2MI = i2miMap_; - std::vector OldI2MBB = Idx2MBBMap; - - Idx2MBBMap.clear(); - MBB2IdxMap.clear(); - mi2iMap_.clear(); - i2miMap_.clear(); - - FunctionSize = 0; - - // Number MachineInstrs and MachineBasicBlocks. - // Initialize MBB indexes to a sentinal. - MBB2IdxMap.resize(mf_->getNumBlockIDs(), std::make_pair(~0U,~0U)); - - unsigned MIIndex = 0; - for (MachineFunction::iterator MBB = mf_->begin(), E = mf_->end(); - MBB != E; ++MBB) { - unsigned StartIdx = MIIndex; - - // Insert an empty slot at the beginning of each block. - MIIndex += InstrSlots::NUM; - i2miMap_.push_back(0); - - for (MachineBasicBlock::iterator I = MBB->begin(), E = MBB->end(); - I != E; ++I) { - bool inserted = mi2iMap_.insert(std::make_pair(I, MIIndex)).second; - assert(inserted && "multiple MachineInstr -> index mappings"); - inserted = true; - i2miMap_.push_back(I); - MIIndex += InstrSlots::NUM; - FunctionSize++; - - // Insert max(1, numdefs) empty slots after every instruction. - unsigned Slots = I->getDesc().getNumDefs(); - if (Slots == 0) - Slots = 1; - MIIndex += InstrSlots::NUM * Slots; - while (Slots--) - i2miMap_.push_back(0); - } - - // Set the MBB2IdxMap entry for this MBB. - MBB2IdxMap[MBB->getNumber()] = std::make_pair(StartIdx, MIIndex - 1); - Idx2MBBMap.push_back(std::make_pair(StartIdx, MBB)); - } - std::sort(Idx2MBBMap.begin(), Idx2MBBMap.end(), Idx2MBBCompare()); - - if (!OldI2MI.empty()) - for (iterator OI = begin(), OE = end(); OI != OE; ++OI) { - for (LiveInterval::iterator LI = OI->second->begin(), - LE = OI->second->end(); LI != LE; ++LI) { - - // Remap the start index of the live range to the corresponding new - // number, or our best guess at what it _should_ correspond to if the - // original instruction has been erased. This is either the following - // instruction or its predecessor. - unsigned index = LI->start / InstrSlots::NUM; - unsigned offset = LI->start % InstrSlots::NUM; - if (offset == InstrSlots::LOAD) { - std::vector::const_iterator I = - std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), LI->start); - // Take the pair containing the index - std::vector::const_iterator J = - (I == OldI2MBB.end() && OldI2MBB.size()>0) ? (I-1): I; - - LI->start = getMBBStartIdx(J->second); - } else { - LI->start = mi2iMap_[OldI2MI[index]] + offset; - } - - // Remap the ending index in the same way that we remapped the start, - // except for the final step where we always map to the immediately - // following instruction. - index = (LI->end - 1) / InstrSlots::NUM; - offset = LI->end % InstrSlots::NUM; - if (offset == InstrSlots::LOAD) { - // VReg dies at end of block. - std::vector::const_iterator I = - std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), LI->end); - --I; - - LI->end = getMBBEndIdx(I->second) + 1; - } else { - unsigned idx = index; - while (index < OldI2MI.size() && !OldI2MI[index]) ++index; - - if (index != OldI2MI.size()) - LI->end = mi2iMap_[OldI2MI[index]] + (idx == index ? offset : 0); - else - LI->end = InstrSlots::NUM * i2miMap_.size(); - } - } - - for (LiveInterval::vni_iterator VNI = OI->second->vni_begin(), - VNE = OI->second->vni_end(); VNI != VNE; ++VNI) { - VNInfo* vni = *VNI; - - // Remap the VNInfo def index, which works the same as the - // start indices above. VN's with special sentinel defs - // don't need to be remapped. - if (vni->def != ~0U && vni->def != ~1U) { - unsigned index = vni->def / InstrSlots::NUM; - unsigned offset = vni->def % InstrSlots::NUM; - if (offset == InstrSlots::LOAD) { - std::vector::const_iterator I = - std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), vni->def); - // Take the pair containing the index - std::vector::const_iterator J = - (I == OldI2MBB.end() && OldI2MBB.size()>0) ? (I-1): I; - - vni->def = getMBBStartIdx(J->second); - } else { - vni->def = mi2iMap_[OldI2MI[index]] + offset; - } - } - - // Remap the VNInfo kill indices, which works the same as - // the end indices above. - for (size_t i = 0; i < vni->kills.size(); ++i) { - // PHI kills don't need to be remapped. - if (!vni->kills[i]) continue; - - unsigned index = (vni->kills[i]-1) / InstrSlots::NUM; - unsigned offset = vni->kills[i] % InstrSlots::NUM; - if (offset == InstrSlots::LOAD) { - std::vector::const_iterator I = - std::lower_bound(OldI2MBB.begin(), OldI2MBB.end(), vni->kills[i]); - --I; - - vni->kills[i] = getMBBEndIdx(I->second); - } else { - unsigned idx = index; - while (index < OldI2MI.size() && !OldI2MI[index]) ++index; - - if (index != OldI2MI.size()) - vni->kills[i] = mi2iMap_[OldI2MI[index]] + - (idx == index ? offset : 0); - else - vni->kills[i] = InstrSlots::NUM * i2miMap_.size(); - } - } - } - } -} - /// runOnMachineFunction - Register allocate the whole function /// bool LiveIntervals::runOnMachineFunction(MachineFunction &fn) { @@ -253,9 +114,9 @@ bool LiveIntervals::runOnMachineFunction(MachineFunction &fn) { tii_ = tm_->getInstrInfo(); aa_ = &getAnalysis(); lv_ = &getAnalysis(); + indexes_ = &getAnalysis(); allocatableRegs_ = tri_->getAllocatableSet(fn); - computeNumbering(); computeIntervals(); numIntervals += getNumIntervals(); @@ -265,83 +126,117 @@ bool LiveIntervals::runOnMachineFunction(MachineFunction &fn) { } /// print - Implement the dump method. -void LiveIntervals::print(std::ostream &O, const Module* ) const { - O << "********** INTERVALS **********\n"; +void LiveIntervals::print(raw_ostream &OS, const Module* ) const { + OS << "********** INTERVALS **********\n"; for (const_iterator I = begin(), E = end(); I != E; ++I) { - I->second->print(O, tri_); - O << "\n"; + I->second->print(OS, tri_); + OS << "\n"; } - O << "********** MACHINEINSTRS **********\n"; + printInstrs(OS); +} + +void LiveIntervals::printInstrs(raw_ostream &OS) const { + OS << "********** MACHINEINSTRS **********\n"; + for (MachineFunction::iterator mbbi = mf_->begin(), mbbe = mf_->end(); mbbi != mbbe; ++mbbi) { - O << ((Value*)mbbi->getBasicBlock())->getName() << ":\n"; + OS << "BB#" << mbbi->getNumber() + << ":\t\t# derived from " << mbbi->getName() << "\n"; for (MachineBasicBlock::iterator mii = mbbi->begin(), mie = mbbi->end(); mii != mie; ++mii) { - O << getInstructionIndex(mii) << '\t' << *mii; + if (mii->isDebugValue()) + OS << " \t" << *mii; + else + OS << getInstructionIndex(mii) << '\t' << *mii; } } } -/// conflictsWithPhysRegDef - Returns true if the specified register -/// is defined during the duration of the specified interval. -bool LiveIntervals::conflictsWithPhysRegDef(const LiveInterval &li, - VirtRegMap &vrm, unsigned reg) { - for (LiveInterval::Ranges::const_iterator - I = li.ranges.begin(), E = li.ranges.end(); I != E; ++I) { - for (unsigned index = getBaseIndex(I->start), - end = getBaseIndex(I->end-1) + InstrSlots::NUM; index != end; - index += InstrSlots::NUM) { - // skip deleted instructions - while (index != end && !getInstructionFromIndex(index)) - index += InstrSlots::NUM; - if (index == end) break; +void LiveIntervals::dumpInstrs() const { + printInstrs(dbgs()); +} - MachineInstr *MI = getInstructionFromIndex(index); - unsigned SrcReg, DstReg, SrcSubReg, DstSubReg; - if (tii_->isMoveInstr(*MI, SrcReg, DstReg, SrcSubReg, DstSubReg)) - if (SrcReg == li.reg || DstReg == li.reg) - continue; - for (unsigned i = 0; i != MI->getNumOperands(); ++i) { - MachineOperand& mop = MI->getOperand(i); - if (!mop.isReg()) - continue; - unsigned PhysReg = mop.getReg(); - if (PhysReg == 0 || PhysReg == li.reg) +bool LiveIntervals::conflictsWithPhysReg(const LiveInterval &li, + VirtRegMap &vrm, unsigned reg) { + // We don't handle fancy stuff crossing basic block boundaries + if (li.ranges.size() != 1) + return true; + const LiveRange &range = li.ranges.front(); + SlotIndex idx = range.start.getBaseIndex(); + SlotIndex end = range.end.getPrevSlot().getBaseIndex().getNextIndex(); + + // Skip deleted instructions + MachineInstr *firstMI = getInstructionFromIndex(idx); + while (!firstMI && idx != end) { + idx = idx.getNextIndex(); + firstMI = getInstructionFromIndex(idx); + } + if (!firstMI) + return false; + + // Find last instruction in range + SlotIndex lastIdx = end.getPrevIndex(); + MachineInstr *lastMI = getInstructionFromIndex(lastIdx); + while (!lastMI && lastIdx != idx) { + lastIdx = lastIdx.getPrevIndex(); + lastMI = getInstructionFromIndex(lastIdx); + } + if (!lastMI) + return false; + + // Range cannot cross basic block boundaries or terminators + MachineBasicBlock *MBB = firstMI->getParent(); + if (MBB != lastMI->getParent() || lastMI->getDesc().isTerminator()) + return true; + + MachineBasicBlock::const_iterator E = lastMI; + ++E; + for (MachineBasicBlock::const_iterator I = firstMI; I != E; ++I) { + const MachineInstr &MI = *I; + + // Allow copies to and from li.reg + unsigned SrcReg, DstReg, SrcSubReg, DstSubReg; + if (tii_->isMoveInstr(MI, SrcReg, DstReg, SrcSubReg, DstSubReg)) + if (SrcReg == li.reg || DstReg == li.reg) + continue; + + // Check for operands using reg + for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) { + const MachineOperand& mop = MI.getOperand(i); + if (!mop.isReg()) + continue; + unsigned PhysReg = mop.getReg(); + if (PhysReg == 0 || PhysReg == li.reg) + continue; + if (TargetRegisterInfo::isVirtualRegister(PhysReg)) { + if (!vrm.hasPhys(PhysReg)) continue; - if (TargetRegisterInfo::isVirtualRegister(PhysReg)) { - if (!vrm.hasPhys(PhysReg)) - continue; - PhysReg = vrm.getPhys(PhysReg); - } - if (PhysReg && tri_->regsOverlap(PhysReg, reg)) - return true; + PhysReg = vrm.getPhys(PhysReg); } + if (PhysReg && tri_->regsOverlap(PhysReg, reg)) + return true; } } + // No conflicts found. return false; } -/// conflictsWithPhysRegRef - Similar to conflictsWithPhysRegRef except -/// it can check use as well. -bool LiveIntervals::conflictsWithPhysRegRef(LiveInterval &li, +/// conflictsWithSubPhysRegRef - Similar to conflictsWithPhysRegRef except +/// it checks for sub-register reference and it can check use as well. +bool LiveIntervals::conflictsWithSubPhysRegRef(LiveInterval &li, unsigned Reg, bool CheckUse, SmallPtrSet &JoinedCopies) { for (LiveInterval::Ranges::const_iterator I = li.ranges.begin(), E = li.ranges.end(); I != E; ++I) { - for (unsigned index = getBaseIndex(I->start), - end = getBaseIndex(I->end-1) + InstrSlots::NUM; index != end; - index += InstrSlots::NUM) { - // Skip deleted instructions. - MachineInstr *MI = 0; - while (index != end) { - MI = getInstructionFromIndex(index); - if (MI) - break; - index += InstrSlots::NUM; - } - if (index == end) break; + for (SlotIndex index = I->start.getBaseIndex(), + end = I->end.getPrevSlot().getBaseIndex().getNextIndex(); + index != end; + index = index.getNextIndex()) { + MachineInstr *MI = getInstructionFromIndex(index); + if (!MI) + continue; // skip deleted instructions if (JoinedCopies.count(MI)) continue; @@ -363,46 +258,46 @@ bool LiveIntervals::conflictsWithPhysRegRef(LiveInterval &li, return false; } - -void LiveIntervals::printRegName(unsigned reg) const { +#ifndef NDEBUG +static void printRegName(unsigned reg, const TargetRegisterInfo* tri_) { if (TargetRegisterInfo::isPhysicalRegister(reg)) - cerr << tri_->getName(reg); + dbgs() << tri_->getName(reg); else - cerr << "%reg" << reg; + dbgs() << "%reg" << reg; } +#endif void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb, MachineBasicBlock::iterator mi, - unsigned MIIdx, MachineOperand& MO, + SlotIndex MIIdx, + MachineOperand& MO, unsigned MOIdx, LiveInterval &interval) { - DOUT << "\t\tregister: "; DEBUG(printRegName(interval.reg)); - LiveVariables::VarInfo& vi = lv_->getVarInfo(interval.reg); - - if (mi->getOpcode() == TargetInstrInfo::IMPLICIT_DEF) { - DOUT << "is a implicit_def\n"; - return; - } + DEBUG({ + dbgs() << "\t\tregister: "; + printRegName(interval.reg, tri_); + }); // Virtual registers may be defined multiple times (due to phi // elimination and 2-addr elimination). Much of what we do only has to be // done once for the vreg. We use an empty interval to detect the first // time we see a vreg. + LiveVariables::VarInfo& vi = lv_->getVarInfo(interval.reg); if (interval.empty()) { // Get the Idx of the defining instructions. - unsigned defIndex = getDefIndex(MIIdx); - // Earlyclobbers move back one. + SlotIndex defIndex = MIIdx.getDefIndex(); + // Earlyclobbers move back one, so that they overlap the live range + // of inputs. if (MO.isEarlyClobber()) - defIndex = getUseIndex(MIIdx); + defIndex = MIIdx.getUseIndex(); VNInfo *ValNo; MachineInstr *CopyMI = NULL; unsigned SrcReg, DstReg, SrcSubReg, DstSubReg; - if (mi->getOpcode() == TargetInstrInfo::EXTRACT_SUBREG || - mi->getOpcode() == TargetInstrInfo::INSERT_SUBREG || + if (mi->isExtractSubreg() || mi->isInsertSubreg() || mi->isSubregToReg() || tii_->isMoveInstr(*mi, SrcReg, DstReg, SrcSubReg, DstSubReg)) CopyMI = mi; // Earlyclobbers move back one. - ValNo = interval.getNextValue(defIndex, CopyMI, VNInfoAllocator); + ValNo = interval.getNextValue(defIndex, CopyMI, true, VNInfoAllocator); assert(ValNo->id == 0 && "First value in interval is not 0?"); @@ -412,21 +307,21 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb, // will be a single kill, in MBB, which comes after the definition. if (vi.Kills.size() == 1 && vi.Kills[0]->getParent() == mbb) { // FIXME: what about dead vars? - unsigned killIdx; + SlotIndex killIdx; if (vi.Kills[0] != mi) - killIdx = getUseIndex(getInstructionIndex(vi.Kills[0]))+1; + killIdx = getInstructionIndex(vi.Kills[0]).getDefIndex(); else - killIdx = defIndex+1; + killIdx = defIndex.getStoreIndex(); // If the kill happens after the definition, we have an intra-block // live range. if (killIdx > defIndex) { - assert(vi.AliveBlocks.none() && + assert(vi.AliveBlocks.empty() && "Shouldn't be alive across any blocks!"); LiveRange LR(defIndex, killIdx, ValNo); interval.addRange(LR); - DOUT << " +" << LR << "\n"; - interval.addKill(ValNo, killIdx); + DEBUG(dbgs() << " +" << LR << "\n"); + ValNo->addKill(killIdx); return; } } @@ -435,32 +330,50 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb, // of the defining block, potentially live across some blocks, then is // live into some number of blocks, but gets killed. Start by adding a // range that goes from this definition to the end of the defining block. - LiveRange NewLR(defIndex, getMBBEndIdx(mbb)+1, ValNo); - DOUT << " +" << NewLR; + LiveRange NewLR(defIndex, getMBBEndIdx(mbb), ValNo); + DEBUG(dbgs() << " +" << NewLR); interval.addRange(NewLR); - // Iterate over all of the blocks that the variable is completely - // live in, adding [insrtIndex(begin), instrIndex(end)+4) to the - // live interval. - for (int i = vi.AliveBlocks.find_first(); i != -1; - i = vi.AliveBlocks.find_next(i)) { - LiveRange LR(getMBBStartIdx(i), - getMBBEndIdx(i)+1, // MBB ends at -1. - ValNo); - interval.addRange(LR); - DOUT << " +" << LR; + bool PHIJoin = lv_->isPHIJoin(interval.reg); + + if (PHIJoin) { + // A phi join register is killed at the end of the MBB and revived as a new + // valno in the killing blocks. + assert(vi.AliveBlocks.empty() && "Phi join can't pass through blocks"); + DEBUG(dbgs() << " phi-join"); + ValNo->addKill(indexes_->getTerminatorGap(mbb)); + ValNo->setHasPHIKill(true); + } else { + // Iterate over all of the blocks that the variable is completely + // live in, adding [insrtIndex(begin), instrIndex(end)+4) to the + // live interval. + for (SparseBitVector<>::iterator I = vi.AliveBlocks.begin(), + E = vi.AliveBlocks.end(); I != E; ++I) { + MachineBasicBlock *aliveBlock = mf_->getBlockNumbered(*I); + LiveRange LR(getMBBStartIdx(aliveBlock), getMBBEndIdx(aliveBlock), ValNo); + interval.addRange(LR); + DEBUG(dbgs() << " +" << LR); + } } // Finally, this virtual register is live from the start of any killing // block to the 'use' slot of the killing instruction. for (unsigned i = 0, e = vi.Kills.size(); i != e; ++i) { MachineInstr *Kill = vi.Kills[i]; - unsigned killIdx = getUseIndex(getInstructionIndex(Kill))+1; - LiveRange LR(getMBBStartIdx(Kill->getParent()), - killIdx, ValNo); + SlotIndex Start = getMBBStartIdx(Kill->getParent()); + SlotIndex killIdx = getInstructionIndex(Kill).getDefIndex(); + + // Create interval with one of a NEW value number. Note that this value + // number isn't actually defined by an instruction, weird huh? :) + if (PHIJoin) { + ValNo = interval.getNextValue(SlotIndex(Start, true), 0, false, + VNInfoAllocator); + ValNo->setIsPHIDef(true); + } + LiveRange LR(Start, killIdx, ValNo); interval.addRange(LR); - interval.addKill(ValNo, killIdx); - DOUT << " +" << LR; + ValNo->addKill(killIdx); + DEBUG(dbgs() << " +" << LR); } } else { @@ -468,19 +381,20 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb, // must be due to phi elimination or two addr elimination. If this is // the result of two address elimination, then the vreg is one of the // def-and-use register operand. - if (mi->isRegReDefinedByTwoAddr(MOIdx)) { + if (mi->isRegTiedToUseOperand(MOIdx)) { // If this is a two-address definition, then we have already processed // the live range. The only problem is that we didn't realize there // are actually two values in the live interval. Because of this we // need to take the LiveRegion that defines this register and split it // into two values. assert(interval.containsOneValue()); - unsigned DefIndex = getDefIndex(interval.getValNumInfo(0)->def); - unsigned RedefIndex = getDefIndex(MIIdx); + SlotIndex DefIndex = interval.getValNumInfo(0)->def.getDefIndex(); + SlotIndex RedefIndex = MIIdx.getDefIndex(); if (MO.isEarlyClobber()) - RedefIndex = getUseIndex(MIIdx); + RedefIndex = MIIdx.getUseIndex(); - const LiveRange *OldLR = interval.getLiveRangeContaining(RedefIndex-1); + const LiveRange *OldLR = + interval.getLiveRangeContaining(RedefIndex.getUseIndex()); VNInfo *OldValNo = OldLR->valno; // Delete the initial value, which should be short and continuous, @@ -493,141 +407,133 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb, // The new value number (#1) is defined by the instruction we claimed // defined value #0. - VNInfo *ValNo = interval.getNextValue(OldValNo->def, OldValNo->copy, + VNInfo *ValNo = interval.getNextValue(OldValNo->def, OldValNo->getCopy(), + false, // update at * VNInfoAllocator); - + ValNo->setFlags(OldValNo->getFlags()); // * <- updating here + // Value#0 is now defined by the 2-addr instruction. OldValNo->def = RedefIndex; - OldValNo->copy = 0; - if (MO.isEarlyClobber()) - OldValNo->redefByEC = true; + OldValNo->setCopy(0); // Add the new live interval which replaces the range for the input copy. LiveRange LR(DefIndex, RedefIndex, ValNo); - DOUT << " replace range with " << LR; + DEBUG(dbgs() << " replace range with " << LR); interval.addRange(LR); - interval.addKill(ValNo, RedefIndex); + ValNo->addKill(RedefIndex); // If this redefinition is dead, we need to add a dummy unit live // range covering the def slot. if (MO.isDead()) - interval.addRange(LiveRange(RedefIndex, RedefIndex+1, OldValNo)); - - DOUT << " RESULT: "; - interval.print(DOUT, tri_); + interval.addRange(LiveRange(RedefIndex, RedefIndex.getStoreIndex(), + OldValNo)); + DEBUG({ + dbgs() << " RESULT: "; + interval.print(dbgs(), tri_); + }); } else { - // Otherwise, this must be because of phi elimination. If this is the - // first redefinition of the vreg that we have seen, go back and change - // the live range in the PHI block to be a different value number. - if (interval.containsOneValue()) { - assert(vi.Kills.size() == 1 && - "PHI elimination vreg should have one kill, the PHI itself!"); - - // Remove the old range that we now know has an incorrect number. - VNInfo *VNI = interval.getValNumInfo(0); - MachineInstr *Killer = vi.Kills[0]; - unsigned Start = getMBBStartIdx(Killer->getParent()); - unsigned End = getUseIndex(getInstructionIndex(Killer))+1; - DOUT << " Removing [" << Start << "," << End << "] from: "; - interval.print(DOUT, tri_); DOUT << "\n"; - interval.removeRange(Start, End); - VNI->hasPHIKill = true; - DOUT << " RESULT: "; interval.print(DOUT, tri_); - - // Replace the interval with one of a NEW value number. Note that this - // value number isn't actually defined by an instruction, weird huh? :) - LiveRange LR(Start, End, interval.getNextValue(~0, 0, VNInfoAllocator)); - DOUT << " replace range with " << LR; - interval.addRange(LR); - interval.addKill(LR.valno, End); - DOUT << " RESULT: "; interval.print(DOUT, tri_); - } - + assert(lv_->isPHIJoin(interval.reg) && "Multiply defined register"); // In the case of PHI elimination, each variable definition is only // live until the end of the block. We've already taken care of the // rest of the live range. - unsigned defIndex = getDefIndex(MIIdx); + + SlotIndex defIndex = MIIdx.getDefIndex(); if (MO.isEarlyClobber()) - defIndex = getUseIndex(MIIdx); - + defIndex = MIIdx.getUseIndex(); + VNInfo *ValNo; MachineInstr *CopyMI = NULL; unsigned SrcReg, DstReg, SrcSubReg, DstSubReg; - if (mi->getOpcode() == TargetInstrInfo::EXTRACT_SUBREG || - mi->getOpcode() == TargetInstrInfo::INSERT_SUBREG || + if (mi->isExtractSubreg() || mi->isInsertSubreg() || mi->isSubregToReg()|| tii_->isMoveInstr(*mi, SrcReg, DstReg, SrcSubReg, DstSubReg)) CopyMI = mi; - ValNo = interval.getNextValue(defIndex, CopyMI, VNInfoAllocator); + ValNo = interval.getNextValue(defIndex, CopyMI, true, VNInfoAllocator); - unsigned killIndex = getMBBEndIdx(mbb) + 1; + SlotIndex killIndex = getMBBEndIdx(mbb); LiveRange LR(defIndex, killIndex, ValNo); interval.addRange(LR); - interval.addKill(ValNo, killIndex); - ValNo->hasPHIKill = true; - DOUT << " +" << LR; + ValNo->addKill(indexes_->getTerminatorGap(mbb)); + ValNo->setHasPHIKill(true); + DEBUG(dbgs() << " phi-join +" << LR); } } - DOUT << '\n'; + DEBUG(dbgs() << '\n'); } void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock *MBB, MachineBasicBlock::iterator mi, - unsigned MIIdx, + SlotIndex MIIdx, MachineOperand& MO, LiveInterval &interval, MachineInstr *CopyMI) { // A physical register cannot be live across basic block, so its // lifetime must end somewhere in its defining basic block. - DOUT << "\t\tregister: "; DEBUG(printRegName(interval.reg)); + DEBUG({ + dbgs() << "\t\tregister: "; + printRegName(interval.reg, tri_); + }); - unsigned baseIndex = MIIdx; - unsigned start = getDefIndex(baseIndex); + SlotIndex baseIndex = MIIdx; + SlotIndex start = baseIndex.getDefIndex(); // Earlyclobbers move back one. if (MO.isEarlyClobber()) - start = getUseIndex(MIIdx); - unsigned end = start; + start = MIIdx.getUseIndex(); + SlotIndex end = start; // If it is not used after definition, it is considered dead at // the instruction defining it. Hence its interval is: // [defSlot(def), defSlot(def)+1) + // For earlyclobbers, the defSlot was pushed back one; the extra + // advance below compensates. if (MO.isDead()) { - DOUT << " dead"; - end = start + 1; + DEBUG(dbgs() << " dead"); + end = start.getStoreIndex(); goto exit; } // If it is not dead on definition, it must be killed by a // subsequent instruction. Hence its interval is: // [defSlot(def), useSlot(kill)+1) - baseIndex += InstrSlots::NUM; + baseIndex = baseIndex.getNextIndex(); while (++mi != MBB->end()) { - while (baseIndex / InstrSlots::NUM < i2miMap_.size() && - getInstructionFromIndex(baseIndex) == 0) - baseIndex += InstrSlots::NUM; + + if (mi->isDebugValue()) + continue; + if (getInstructionFromIndex(baseIndex) == 0) + baseIndex = indexes_->getNextNonNullIndex(baseIndex); + if (mi->killsRegister(interval.reg, tri_)) { - DOUT << " killed"; - end = getUseIndex(baseIndex) + 1; - goto exit; - } 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) - DOUT << " dead"; - end = start + 1; + DEBUG(dbgs() << " killed"); + end = baseIndex.getDefIndex(); goto exit; + } else { + int DefIdx = mi->findRegisterDefOperandIdx(interval.reg, false, tri_); + if (DefIdx != -1) { + if (mi->isRegTiedToUseOperand(DefIdx)) { + // Two-address instruction. + 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: + // [defSlot(def), defSlot(def)+1) + DEBUG(dbgs() << " dead"); + end = start.getStoreIndex(); + } + goto exit; + } } - baseIndex += InstrSlots::NUM; + baseIndex = baseIndex.getNextIndex(); } // The only case we should have a dead physreg here without a killing or // instruction where we know it's dead is if it is live-in to the function - // and never used. - assert(!CopyMI && "physreg was not killed in defining block!"); - end = start + 1; + // and never used. Another possible case is the implicit use of the + // physical register has been deleted by two-address pass. + end = start.getStoreIndex(); exit: assert(start < end && "did not find end of interval?"); @@ -636,18 +542,18 @@ exit: LiveInterval::iterator OldLR = interval.FindLiveRangeContaining(start); bool Extend = OldLR != interval.end(); VNInfo *ValNo = Extend - ? OldLR->valno : interval.getNextValue(start, CopyMI, VNInfoAllocator); + ? OldLR->valno : interval.getNextValue(start, CopyMI, true, VNInfoAllocator); if (MO.isEarlyClobber() && Extend) - ValNo->redefByEC = true; + ValNo->setHasRedefByEC(true); LiveRange LR(start, end, ValNo); interval.addRange(LR); - interval.addKill(LR.valno, end); - DOUT << " +" << LR << '\n'; + LR.valno->addKill(end); + DEBUG(dbgs() << " +" << LR << '\n'); } void LiveIntervals::handleRegisterDef(MachineBasicBlock *MBB, MachineBasicBlock::iterator MI, - unsigned MIIdx, + SlotIndex MIIdx, MachineOperand& MO, unsigned MOIdx) { if (TargetRegisterInfo::isVirtualRegister(MO.getReg())) @@ -656,80 +562,94 @@ void LiveIntervals::handleRegisterDef(MachineBasicBlock *MBB, else if (allocatableRegs_[MO.getReg()]) { MachineInstr *CopyMI = NULL; unsigned SrcReg, DstReg, SrcSubReg, DstSubReg; - if (MI->getOpcode() == TargetInstrInfo::EXTRACT_SUBREG || - MI->getOpcode() == TargetInstrInfo::INSERT_SUBREG || + if (MI->isExtractSubreg() || MI->isInsertSubreg() || MI->isSubregToReg() || tii_->isMoveInstr(*MI, SrcReg, DstReg, SrcSubReg, DstSubReg)) CopyMI = MI; - handlePhysicalRegisterDef(MBB, MI, MIIdx, MO, + handlePhysicalRegisterDef(MBB, MI, MIIdx, MO, getOrCreateInterval(MO.getReg()), CopyMI); // Def of a register also defines its sub-registers. for (const unsigned* AS = tri_->getSubRegisters(MO.getReg()); *AS; ++AS) // If MI also modifies the sub-register explicitly, avoid processing it // more than once. Do not pass in TRI here so it checks for exact match. if (!MI->modifiesRegister(*AS)) - handlePhysicalRegisterDef(MBB, MI, MIIdx, MO, + handlePhysicalRegisterDef(MBB, MI, MIIdx, MO, getOrCreateInterval(*AS), 0); } } void LiveIntervals::handleLiveInRegister(MachineBasicBlock *MBB, - unsigned MIIdx, + SlotIndex MIIdx, LiveInterval &interval, bool isAlias) { - DOUT << "\t\tlivein register: "; DEBUG(printRegName(interval.reg)); + DEBUG({ + dbgs() << "\t\tlivein register: "; + printRegName(interval.reg, tri_); + }); // Look for kills, if it reaches a def before it's killed, then it shouldn't // be considered a livein. MachineBasicBlock::iterator mi = MBB->begin(); - unsigned baseIndex = MIIdx; - unsigned start = baseIndex; - while (baseIndex / InstrSlots::NUM < i2miMap_.size() && - getInstructionFromIndex(baseIndex) == 0) - baseIndex += InstrSlots::NUM; - unsigned end = baseIndex; + MachineBasicBlock::iterator E = MBB->end(); + // Skip over DBG_VALUE at the start of the MBB. + if (mi != E && mi->isDebugValue()) { + while (++mi != E && mi->isDebugValue()) + ; + if (mi == E) + // MBB is empty except for DBG_VALUE's. + return; + } + + SlotIndex baseIndex = MIIdx; + SlotIndex start = baseIndex; + if (getInstructionFromIndex(baseIndex) == 0) + baseIndex = indexes_->getNextNonNullIndex(baseIndex); + + SlotIndex end = baseIndex; bool SeenDefUse = false; - - while (mi != MBB->end()) { + + while (mi != E) { if (mi->killsRegister(interval.reg, tri_)) { - DOUT << " killed"; - end = getUseIndex(baseIndex) + 1; + DEBUG(dbgs() << " killed"); + end = baseIndex.getDefIndex(); SeenDefUse = true; - goto exit; + 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) - DOUT << " dead"; - end = getDefIndex(start) + 1; + DEBUG(dbgs() << " dead"); + end = start.getStoreIndex(); SeenDefUse = true; - goto exit; + break; } - baseIndex += InstrSlots::NUM; - ++mi; - if (mi != MBB->end()) { - while (baseIndex / InstrSlots::NUM < i2miMap_.size() && - getInstructionFromIndex(baseIndex) == 0) - baseIndex += InstrSlots::NUM; - } + while (++mi != E && mi->isDebugValue()) + // Skip over DBG_VALUE. + ; + if (mi != E) + baseIndex = indexes_->getNextNonNullIndex(baseIndex); } -exit: // Live-in register might not be used at all. if (!SeenDefUse) { if (isAlias) { - DOUT << " dead"; - end = getDefIndex(MIIdx) + 1; + DEBUG(dbgs() << " dead"); + end = MIIdx.getStoreIndex(); } else { - DOUT << " live through"; + DEBUG(dbgs() << " live through"); end = baseIndex; } } - LiveRange LR(start, end, interval.getNextValue(~0U, 0, VNInfoAllocator)); + VNInfo *vni = + interval.getNextValue(SlotIndex(getMBBStartIdx(MBB), true), + 0, false, VNInfoAllocator); + vni->setIsPHIDef(true); + LiveRange LR(start, end, vni); + interval.addRange(LR); - interval.addKill(LR.valno, end); - DOUT << " +" << LR << '\n'; + LR.valno->addKill(end); + DEBUG(dbgs() << " +" << LR << '\n'); } /// computeIntervals - computes the live intervals for virtual @@ -737,19 +657,20 @@ exit: /// live interval is an interval [i, j) where 1 <= i <= j < N for /// which a variable is live void LiveIntervals::computeIntervals() { + DEBUG(dbgs() << "********** COMPUTING LIVE INTERVALS **********\n" + << "********** Function: " + << ((Value*)mf_->getFunction())->getName() << '\n'); - DOUT << "********** COMPUTING LIVE INTERVALS **********\n" - << "********** Function: " - << ((Value*)mf_->getFunction())->getName() << '\n'; - + SmallVector UndefUses; for (MachineFunction::iterator MBBI = mf_->begin(), E = mf_->end(); MBBI != E; ++MBBI) { MachineBasicBlock *MBB = MBBI; - // Track the index of the current machine instr. - unsigned MIIndex = getMBBStartIdx(MBB); - DOUT << ((Value*)MBB->getBasicBlock())->getName() << ":\n"; + if (MBB->empty()) + continue; - MachineBasicBlock::iterator MI = MBB->begin(), miEnd = MBB->end(); + // Track the index of the current machine instr. + SlotIndex MIIndex = getMBBStartIdx(MBB); + DEBUG(dbgs() << MBB->getName() << ":\n"); // Create intervals for live-ins to this BB first. for (MachineBasicBlock::const_livein_iterator LI = MBB->livein_begin(), @@ -763,71 +684,40 @@ void LiveIntervals::computeIntervals() { } // Skip over empty initial indices. - while (MIIndex / InstrSlots::NUM < i2miMap_.size() && - getInstructionFromIndex(MIIndex) == 0) - MIIndex += InstrSlots::NUM; + if (getInstructionFromIndex(MIIndex) == 0) + MIIndex = indexes_->getNextNonNullIndex(MIIndex); - for (; MI != miEnd; ++MI) { - DOUT << MIIndex << "\t" << *MI; + for (MachineBasicBlock::iterator MI = MBB->begin(), miEnd = MBB->end(); + MI != miEnd; ++MI) { + DEBUG(dbgs() << MIIndex << "\t" << *MI); + if (MI->isDebugValue()) + continue; // Handle defs. for (int i = MI->getNumOperands() - 1; i >= 0; --i) { MachineOperand &MO = MI->getOperand(i); + if (!MO.isReg() || !MO.getReg()) + continue; + // handle register defs - build intervals - if (MO.isReg() && MO.getReg() && MO.isDef()) { + if (MO.isDef()) handleRegisterDef(MBB, MI, MIIndex, MO, i); - } + else if (MO.isUndef()) + UndefUses.push_back(MO.getReg()); } - - // Skip over the empty slots after each instruction. - unsigned Slots = MI->getDesc().getNumDefs(); - if (Slots == 0) - Slots = 1; - MIIndex += InstrSlots::NUM * Slots; - // Skip over empty indices. - while (MIIndex / InstrSlots::NUM < i2miMap_.size() && - getInstructionFromIndex(MIIndex) == 0) - MIIndex += InstrSlots::NUM; + // Move to the next instr slot. + MIIndex = indexes_->getNextNonNullIndex(MIIndex); } } -} - -bool LiveIntervals::findLiveInMBBs(unsigned Start, unsigned End, - SmallVectorImpl &MBBs) const { - std::vector::const_iterator I = - std::lower_bound(Idx2MBBMap.begin(), Idx2MBBMap.end(), Start); - bool ResVal = false; - while (I != Idx2MBBMap.end()) { - if (I->first >= End) - break; - MBBs.push_back(I->second); - ResVal = true; - ++I; + // Create empty intervals for registers defined by implicit_def's (except + // for those implicit_def that define values which are liveout of their + // blocks. + for (unsigned i = 0, e = UndefUses.size(); i != e; ++i) { + unsigned UndefReg = UndefUses[i]; + (void)getOrCreateInterval(UndefReg); } - return ResVal; -} - -bool LiveIntervals::findReachableMBBs(unsigned Start, unsigned End, - SmallVectorImpl &MBBs) const { - std::vector::const_iterator I = - std::lower_bound(Idx2MBBMap.begin(), Idx2MBBMap.end(), Start); - - bool ResVal = false; - while (I != Idx2MBBMap.end()) { - if (I->first > End) - break; - MachineBasicBlock *MBB = I->second; - if (getMBBEndIdx(MBB) > End) - break; - for (MachineBasicBlock::succ_iterator SI = MBB->succ_begin(), - SE = MBB->succ_end(); SI != SE; ++SI) - MBBs.push_back(*SI); - ResVal = true; - ++I; - } - return ResVal; } LiveInterval* LiveIntervals::createInterval(unsigned reg) { @@ -839,29 +729,38 @@ LiveInterval* LiveIntervals::createInterval(unsigned reg) { /// managing the allocated memory. LiveInterval* LiveIntervals::dupInterval(LiveInterval *li) { LiveInterval *NewLI = createInterval(li->reg); - NewLI->Copy(*li, getVNInfoAllocator()); + NewLI->Copy(*li, mri_, getVNInfoAllocator()); return NewLI; } /// getVNInfoSourceReg - Helper function that parses the specified VNInfo /// copy field and returns the source register that defines it. unsigned LiveIntervals::getVNInfoSourceReg(const VNInfo *VNI) const { - if (!VNI->copy) + if (!VNI->getCopy()) return 0; - if (VNI->copy->getOpcode() == TargetInstrInfo::EXTRACT_SUBREG) { + if (VNI->getCopy()->isExtractSubreg()) { // If it's extracting out of a physical register, return the sub-register. - unsigned Reg = VNI->copy->getOperand(1).getReg(); - if (TargetRegisterInfo::isPhysicalRegister(Reg)) - Reg = tri_->getSubReg(Reg, VNI->copy->getOperand(2).getImm()); + unsigned Reg = VNI->getCopy()->getOperand(1).getReg(); + if (TargetRegisterInfo::isPhysicalRegister(Reg)) { + unsigned SrcSubReg = VNI->getCopy()->getOperand(2).getImm(); + unsigned DstSubReg = VNI->getCopy()->getOperand(0).getSubReg(); + if (SrcSubReg == DstSubReg) + // %reg1034:3 = EXTRACT_SUBREG %EDX, 3 + // reg1034 can still be coalesced to EDX. + return Reg; + assert(DstSubReg == 0); + Reg = tri_->getSubReg(Reg, VNI->getCopy()->getOperand(2).getImm()); + } return Reg; - } else if (VNI->copy->getOpcode() == TargetInstrInfo::INSERT_SUBREG) - return VNI->copy->getOperand(2).getReg(); + } else if (VNI->getCopy()->isInsertSubreg() || + VNI->getCopy()->isSubregToReg()) + return VNI->getCopy()->getOperand(2).getReg(); unsigned SrcReg, DstReg, SrcSubReg, DstSubReg; - if (tii_->isMoveInstr(*VNI->copy, SrcReg, DstReg, SrcSubReg, DstSubReg)) + if (tii_->isMoveInstr(*VNI->getCopy(), SrcReg, DstReg, SrcSubReg, DstSubReg)) return SrcReg; - assert(0 && "Unrecognized copy instruction!"); + llvm_unreachable("Unrecognized copy instruction!"); return 0; } @@ -882,6 +781,10 @@ unsigned LiveIntervals::getReMatImplicitUse(const LiveInterval &li, unsigned Reg = MO.getReg(); if (Reg == 0 || Reg == li.reg) continue; + + if (TargetRegisterInfo::isPhysicalRegister(Reg) && + !allocatableRegs_[Reg]) + continue; // FIXME: For now, only remat MI with at most one register operand. assert(!RegOp && "Can't rematerialize instruction with multiple register operand!"); @@ -896,8 +799,8 @@ unsigned LiveIntervals::getReMatImplicitUse(const LiveInterval &li, /// isValNoAvailableAt - Return true if the val# of the specified interval /// which reaches the given instruction also reaches the specified use index. bool LiveIntervals::isValNoAvailableAt(const LiveInterval &li, MachineInstr *MI, - unsigned UseIdx) const { - unsigned Index = getInstructionIndex(MI); + SlotIndex UseIdx) const { + SlotIndex Index = getInstructionIndex(MI); VNInfo *ValNo = li.FindLiveRangeContaining(Index)->valno; LiveInterval::const_iterator UI = li.FindLiveRangeContaining(UseIdx); return UI != li.end() && UI->valno == ValNo; @@ -912,102 +815,20 @@ bool LiveIntervals::isReMaterializable(const LiveInterval &li, if (DisableReMat) return false; - if (MI->getOpcode() == TargetInstrInfo::IMPLICIT_DEF) - return true; - - int FrameIdx = 0; - if (tii_->isLoadFromStackSlot(MI, FrameIdx) && - mf_->getFrameInfo()->isImmutableObjectIndex(FrameIdx)) - // FIXME: Let target specific isReallyTriviallyReMaterializable determines - // this but remember this is not safe to fold into a two-address - // instruction. - // This is a load from fixed stack slot. It can be rematerialized. - return true; - - // If the target-specific rules don't identify an instruction as - // being trivially rematerializable, use some target-independent - // rules. - if (!MI->getDesc().isRematerializable() || - !tii_->isTriviallyReMaterializable(MI)) { - if (!EnableAggressiveRemat) - return false; - - // If the instruction accesses memory but the memoperands have been lost, - // we can't analyze it. - const TargetInstrDesc &TID = MI->getDesc(); - if ((TID.mayLoad() || TID.mayStore()) && MI->memoperands_empty()) - return false; - - // Avoid instructions obviously unsafe for remat. - if (TID.hasUnmodeledSideEffects() || TID.isNotDuplicable()) - return false; - - // If the instruction accesses memory and the memory could be non-constant, - // assume the instruction is not rematerializable. - for (std::list::const_iterator - I = MI->memoperands_begin(), E = MI->memoperands_end(); I != E; ++I){ - const MachineMemOperand &MMO = *I; - if (MMO.isVolatile() || MMO.isStore()) - return false; - const Value *V = MMO.getValue(); - if (!V) - return false; - if (const PseudoSourceValue *PSV = dyn_cast(V)) { - if (!PSV->isConstant(mf_->getFrameInfo())) - return false; - } else if (!aa_->pointsToConstantMemory(V)) - return false; - } - - // If any of the registers accessed are non-constant, conservatively assume - // the instruction is not rematerializable. - unsigned ImpUse = 0; - for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { - const MachineOperand &MO = MI->getOperand(i); - if (MO.isReg()) { - unsigned Reg = MO.getReg(); - if (Reg == 0) - continue; - if (TargetRegisterInfo::isPhysicalRegister(Reg)) - return false; - - // Only allow one def, and that in the first operand. - if (MO.isDef() != (i == 0)) - return false; - - // Only allow constant-valued registers. - bool IsLiveIn = mri_->isLiveIn(Reg); - MachineRegisterInfo::def_iterator I = mri_->def_begin(Reg), - E = mri_->def_end(); - - // For the def, it should be the only def of that register. - if (MO.isDef() && (next(I) != E || IsLiveIn)) - return false; - - if (MO.isUse()) { - // Only allow one use other register use, as that's all the - // remat mechanisms support currently. - if (Reg != li.reg) { - if (ImpUse == 0) - ImpUse = Reg; - else if (Reg != ImpUse) - return false; - } - // For the use, there should be only one associated def. - if (I != E && (next(I) != E || IsLiveIn)) - return false; - } - } - } - } + if (!tii_->isTriviallyReMaterializable(MI, aa_)) + return false; + // Target-specific code can mark an instruction as being rematerializable + // if it has one virtual reg use, though it had better be something like + // a PIC base register which is likely to be live everywhere. unsigned ImpUse = getReMatImplicitUse(li, MI); if (ImpUse) { const LiveInterval &ImpLi = getInterval(ImpUse); - for (MachineRegisterInfo::use_iterator ri = mri_->use_begin(li.reg), - re = mri_->use_end(); ri != re; ++ri) { + for (MachineRegisterInfo::use_nodbg_iterator + ri = mri_->use_nodbg_begin(li.reg), re = mri_->use_nodbg_end(); + ri != re; ++ri) { MachineInstr *UseMI = &*ri; - unsigned UseIdx = getInstructionIndex(UseMI); + SlotIndex UseIdx = getInstructionIndex(UseMI); if (li.FindLiveRangeContaining(UseIdx)->valno != ValNo) continue; if (!isValNoAvailableAt(ImpLi, MI, UseIdx)) @@ -1041,13 +862,12 @@ bool LiveIntervals::isReMaterializable(const LiveInterval &li, for (LiveInterval::const_vni_iterator i = li.vni_begin(), e = li.vni_end(); i != e; ++i) { const VNInfo *VNI = *i; - unsigned DefIdx = VNI->def; - if (DefIdx == ~1U) + if (VNI->isUnused()) continue; // Dead val#. // Is the def for the val# rematerializable? - if (DefIdx == ~0u) + if (!VNI->isDefAccurate()) return false; - MachineInstr *ReMatDefMI = getInstructionFromIndex(DefIdx); + MachineInstr *ReMatDefMI = getInstructionFromIndex(VNI->def); bool DefIsLoad = false; if (!ReMatDefMI || !isReMaterializable(li, VNI, ReMatDefMI, SpillIs, DefIsLoad)) @@ -1093,11 +913,11 @@ static bool FilterFoldedOps(MachineInstr *MI, /// returns true. bool LiveIntervals::tryFoldMemoryOperand(MachineInstr* &MI, VirtRegMap &vrm, MachineInstr *DefMI, - unsigned InstrIdx, + SlotIndex InstrIdx, SmallVector &Ops, bool isSS, int Slot, unsigned Reg) { // If it is an implicit def instruction, just delete it. - if (MI->getOpcode() == TargetInstrInfo::IMPLICIT_DEF) { + if (MI->isImplicitDef()) { RemoveMachineInstrFromMaps(MI); vrm.RemoveMachineInstrFromMaps(MI); MI->eraseFromParent(); @@ -1131,9 +951,7 @@ bool LiveIntervals::tryFoldMemoryOperand(MachineInstr* &MI, vrm.transferSpillPts(MI, fmi); vrm.transferRestorePts(MI, fmi); vrm.transferEmergencySpills(MI, fmi); - mi2iMap_.erase(MI); - i2miMap_[InstrIdx /InstrSlots::NUM] = fmi; - mi2iMap_[fmi] = InstrIdx; + ReplaceMachineInstrInMaps(MI, fmi); MI = MBB.insert(MBB.erase(MI), fmi); ++numFolds; return true; @@ -1161,19 +979,21 @@ bool LiveIntervals::canFoldMemoryOperand(MachineInstr *MI, } bool LiveIntervals::intervalIsInOneMBB(const LiveInterval &li) const { - SmallPtrSet MBBs; - for (LiveInterval::Ranges::const_iterator - I = li.ranges.begin(), E = li.ranges.end(); I != E; ++I) { - std::vector::const_iterator II = - std::lower_bound(Idx2MBBMap.begin(), Idx2MBBMap.end(), I->start); - if (II == Idx2MBBMap.end()) - continue; - if (I->end > II->first) // crossing a MBB. - return false; - MBBs.insert(II->second); - if (MBBs.size() > 1) + LiveInterval::Ranges::const_iterator itr = li.ranges.begin(); + + MachineBasicBlock *mbb = indexes_->getMBBCoveringRange(itr->start, itr->end); + + if (mbb == 0) + return false; + + for (++itr; itr != li.ranges.end(); ++itr) { + MachineBasicBlock *mbb2 = + indexes_->getMBBCoveringRange(itr->start, itr->end); + + if (mbb2 != mbb) return false; } + return true; } @@ -1205,7 +1025,8 @@ void LiveIntervals::rewriteImplicitOps(const LiveInterval &li, /// for addIntervalsForSpills to rewrite uses / defs for the given live range. bool LiveIntervals:: rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI, - bool TrySplit, unsigned index, unsigned end, MachineInstr *MI, + bool TrySplit, SlotIndex index, SlotIndex end, + MachineInstr *MI, MachineInstr *ReMatOrigDefMI, MachineInstr *ReMatDefMI, unsigned Slot, int LdSlot, bool isLoad, bool isLoadSS, bool DefIsReMat, bool CanDelete, @@ -1215,9 +1036,7 @@ rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI, const MachineLoopInfo *loopInfo, unsigned &NewVReg, unsigned ImpUse, bool &HasDef, bool &HasUse, DenseMap &MBBVRegsMap, - std::vector &NewLIs, float &SSWeight) { - MachineBasicBlock *MBB = MI->getParent(); - unsigned loopDepth = loopInfo->getLoopDepth(MBB); + std::vector &NewLIs) { bool CanFold = false; RestartInstruction: for (unsigned i = 0; i != MI->getNumOperands(); ++i) { @@ -1238,8 +1057,8 @@ 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) { - DOUT << "\t\t\t\tErasing re-materlizable def: "; - DOUT << MI << '\n'; + DEBUG(dbgs() << "\t\t\t\tErasing re-materializable def: " + << *MI << '\n'); RemoveMachineInstrFromMaps(MI); vrm.RemoveMachineInstrFromMaps(MI); MI->eraseFromParent(); @@ -1281,28 +1100,13 @@ rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI, continue; if (RegJ == RegI) { Ops.push_back(j); - HasUse |= MOj.isUse(); - HasDef |= MOj.isDef(); + if (!MOj.isUndef()) { + HasUse |= MOj.isUse(); + HasDef |= MOj.isDef(); + } } } - if (HasUse && !li.liveAt(getUseIndex(index))) - // Must be defined by an implicit def. It should not be spilled. Note, - // this is for correctness reason. e.g. - // 8 %reg1024 = IMPLICIT_DEF - // 12 %reg1024 = INSERT_SUBREG %reg1024, %reg1025, 2 - // The live range [12, 14) are not part of the r1024 live interval since - // it's defined by an implicit def. It will not conflicts with live - // interval of r1025. Now suppose both registers are spilled, you can - // easily see a situation where both registers are reloaded before - // the INSERT_SUBREG and both target registers that would overlap. - HasUse = false; - - // Update stack slot spill weight if we are splitting. - float Weight = getSpillWeight(HasDef, HasUse, loopDepth); - if (!TrySplit) - SSWeight += Weight; - // Create a new virtual register for the spill interval. // Create the new register now so we can map the fold instruction // to the new register so when it is unfolded we get the correct @@ -1312,6 +1116,12 @@ rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI, NewVReg = mri_->createVirtualRegister(rc); vrm.grow(); CreatedNewVReg = true; + + // The new virtual register should get the same allocation hints as the + // old one. + std::pair Hint = mri_->getRegAllocationHint(Reg); + if (Hint.first || Hint.second) + mri_->setRegAllocationHint(NewVReg, Hint.first, Hint.second); } if (!TryFold) @@ -1334,10 +1144,8 @@ rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI, HasUse = false; HasDef = false; CanFold = false; - if (isRemoved(MI)) { - SSWeight -= Weight; + if (isNotInMIMap(MI)) break; - } goto RestartInstruction; } } else { @@ -1360,7 +1168,7 @@ rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI, if (CreatedNewVReg) { if (DefIsReMat) { - vrm.setVirtIsReMaterialized(NewVReg, ReMatDefMI/*, CanDelete*/); + vrm.setVirtIsReMaterialized(NewVReg, ReMatDefMI); if (ReMatIds[VNI->id] == VirtRegMap::MAX_STACK_SLOT) { // Each valnum may have its own remat id. ReMatIds[VNI->id] = vrm.assignVirtReMatId(NewVReg); @@ -1389,7 +1197,7 @@ rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI, if (DefIsReMat && ImpUse) MI->addOperand(MachineOperand::CreateReg(ImpUse, false, true)); - // create a new register interval for this spill / remat. + // Create a new register interval for this spill / remat. LiveInterval &nI = getOrCreateInterval(NewVReg); if (CreatedNewVReg) { NewLIs.push_back(&nI); @@ -1400,39 +1208,45 @@ rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI, if (HasUse) { if (CreatedNewVReg) { - LiveRange LR(getLoadIndex(index), getUseIndex(index)+1, - nI.getNextValue(~0U, 0, VNInfoAllocator)); - DOUT << " +" << LR; + LiveRange LR(index.getLoadIndex(), index.getDefIndex(), + nI.getNextValue(SlotIndex(), 0, false, VNInfoAllocator)); + DEBUG(dbgs() << " +" << LR); nI.addRange(LR); } else { // Extend the split live interval to this def / use. - unsigned End = getUseIndex(index)+1; + SlotIndex End = index.getDefIndex(); LiveRange LR(nI.ranges[nI.ranges.size()-1].end, End, nI.getValNumInfo(nI.getNumValNums()-1)); - DOUT << " +" << LR; + DEBUG(dbgs() << " +" << LR); nI.addRange(LR); } } if (HasDef) { - LiveRange LR(getDefIndex(index), getStoreIndex(index), - nI.getNextValue(~0U, 0, VNInfoAllocator)); - DOUT << " +" << LR; + LiveRange LR(index.getDefIndex(), index.getStoreIndex(), + nI.getNextValue(SlotIndex(), 0, false, VNInfoAllocator)); + DEBUG(dbgs() << " +" << LR); nI.addRange(LR); } - DOUT << "\t\t\t\tAdded new interval: "; - nI.print(DOUT, tri_); - DOUT << '\n'; + DEBUG({ + dbgs() << "\t\t\t\tAdded new interval: "; + nI.print(dbgs(), tri_); + dbgs() << '\n'; + }); } return CanFold; } bool LiveIntervals::anyKillInMBBAfterIdx(const LiveInterval &li, const VNInfo *VNI, - MachineBasicBlock *MBB, unsigned Idx) const { - unsigned End = getMBBEndIdx(MBB); + MachineBasicBlock *MBB, + SlotIndex Idx) const { + SlotIndex End = getMBBEndIdx(MBB); for (unsigned j = 0, ee = VNI->kills.size(); j != ee; ++j) { - unsigned KillIdx = VNI->kills[j]; - if (KillIdx > Idx && KillIdx < End) + if (VNI->kills[j].isPHI()) + continue; + + SlotIndex KillIdx = VNI->kills[j]; + if (KillIdx > Idx && KillIdx <= End) return true; } return false; @@ -1442,11 +1256,11 @@ bool LiveIntervals::anyKillInMBBAfterIdx(const LiveInterval &li, /// during spilling. namespace { struct RewriteInfo { - unsigned Index; + SlotIndex Index; MachineInstr *MI; bool HasUse; bool HasDef; - RewriteInfo(unsigned i, MachineInstr *mi, bool u, bool d) + RewriteInfo(SlotIndex i, MachineInstr *mi, bool u, bool d) : Index(i), MI(mi), HasUse(u), HasDef(d) {} }; @@ -1472,11 +1286,11 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, BitVector &RestoreMBBs, DenseMap > &RestoreIdxes, DenseMap &MBBVRegsMap, - std::vector &NewLIs, float &SSWeight) { + std::vector &NewLIs) { bool AllCanFold = true; unsigned NewVReg = 0; - unsigned start = getBaseIndex(I->start); - unsigned end = getBaseIndex(I->end-1) + InstrSlots::NUM; + SlotIndex start = I->start.getBaseIndex(); + SlotIndex end = I->end.getPrevSlot().getBaseIndex().getNextIndex(); // First collect all the def / use in this live range that will be rewritten. // Make sure they are sorted according to instruction index. @@ -1486,11 +1300,18 @@ 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?"); - unsigned index = getInstructionIndex(MI); + SlotIndex index = getInstructionIndex(MI); if (index < start || index >= end) continue; - if (O.isUse() && !li.liveAt(getUseIndex(index))) + + if (O.isUndef()) // Must be defined by an implicit def. It should not be spilled. Note, // this is for correctness reason. e.g. // 8 %reg1024 = IMPLICIT_DEF @@ -1510,7 +1331,7 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, for (unsigned i = 0, e = RewriteMIs.size(); i != e; ) { RewriteInfo &rwi = RewriteMIs[i]; ++i; - unsigned index = rwi.Index; + SlotIndex index = rwi.Index; bool MIHasUse = rwi.HasUse; bool MIHasDef = rwi.HasDef; MachineInstr *MI = rwi.MI; @@ -1528,11 +1349,9 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, MachineBasicBlock *MBB = MI->getParent(); if (ImpUse && MI != ReMatDefMI) { - // Re-matting an instruction with virtual register use. Update the - // register interval's spill weight to HUGE_VALF to prevent it from - // being spilled. - LiveInterval &ImpLi = getInterval(ImpUse); - ImpLi.weight = HUGE_VALF; + // Re-matting an instruction with virtual register use. Prevent interval + // from being spilled. + getInterval(ImpUse).markNotSpillable(); } unsigned MBBId = MBB->getNumber(); @@ -1574,7 +1393,7 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, index, end, MI, ReMatOrigDefMI, ReMatDefMI, Slot, LdSlot, isLoad, isLoadSS, DefIsReMat, CanDelete, vrm, rc, ReMatIds, loopInfo, NewVReg, - ImpUse, HasDef, HasUse, MBBVRegsMap, NewLIs, SSWeight); + ImpUse, HasDef, HasUse, MBBVRegsMap, NewLIs); if (!HasDef && !HasUse) continue; @@ -1584,7 +1403,7 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, LiveInterval &nI = getOrCreateInterval(NewVReg); if (!TrySplit) { // The spill weight is now infinity as it cannot be spilled again. - nI.weight = HUGE_VALF; + nI.markNotSpillable(); continue; } @@ -1593,12 +1412,12 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, if (MI != ReMatOrigDefMI || !CanDelete) { bool HasKill = false; if (!HasUse) - HasKill = anyKillInMBBAfterIdx(li, I->valno, MBB, getDefIndex(index)); + HasKill = anyKillInMBBAfterIdx(li, I->valno, MBB, index.getDefIndex()); else { // If this is a two-address code, then this index starts a new VNInfo. - const VNInfo *VNI = li.findDefinedVNInfo(getDefIndex(index)); + const VNInfo *VNI = li.findDefinedVNInfoForRegInt(index.getDefIndex()); if (VNI) - HasKill = anyKillInMBBAfterIdx(li, VNI, MBB, getDefIndex(index)); + HasKill = anyKillInMBBAfterIdx(li, VNI, MBB, index.getDefIndex()); } DenseMap >::iterator SII = SpillIdxes.find(MBBId); @@ -1609,7 +1428,7 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, SpillIdxes.insert(std::make_pair(MBBId, S)); } else if (SII->second.back().vreg != NewVReg) { SII->second.push_back(SRInfo(index, NewVReg, true)); - } else if ((int)index > SII->second.back().index) { + } else if (index > SII->second.back().index) { // If there is an earlier def and this is a two-address // instruction, then it's not possible to fold the store (which // would also fold the load). @@ -1620,7 +1439,7 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, SpillMBBs.set(MBBId); } else if (SII != SpillIdxes.end() && SII->second.back().vreg == NewVReg && - (int)index > SII->second.back().index) { + index > SII->second.back().index) { // There is an earlier def that's not killed (must be two-address). // The spill is no longer needed. SII->second.pop_back(); @@ -1637,7 +1456,7 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, SpillIdxes.find(MBBId); if (SII != SpillIdxes.end() && SII->second.back().vreg == NewVReg && - (int)index > SII->second.back().index) + index > SII->second.back().index) // Use(s) following the last def, it's not safe to fold the spill. SII->second.back().canFold = false; DenseMap >::iterator RII = @@ -1671,8 +1490,8 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit, } } -bool LiveIntervals::alsoFoldARestore(int Id, int index, unsigned vr, - BitVector &RestoreMBBs, +bool LiveIntervals::alsoFoldARestore(int Id, SlotIndex index, + unsigned vr, BitVector &RestoreMBBs, DenseMap > &RestoreIdxes) { if (!RestoreMBBs[Id]) return false; @@ -1685,15 +1504,15 @@ bool LiveIntervals::alsoFoldARestore(int Id, int index, unsigned vr, return false; } -void LiveIntervals::eraseRestoreInfo(int Id, int index, unsigned vr, - BitVector &RestoreMBBs, +void LiveIntervals::eraseRestoreInfo(int Id, SlotIndex index, + unsigned vr, BitVector &RestoreMBBs, DenseMap > &RestoreIdxes) { if (!RestoreMBBs[Id]) return; std::vector &Restores = RestoreIdxes[Id]; for (unsigned i = 0, e = Restores.size(); i != e; ++i) if (Restores[i].index == index && Restores[i].vreg) - Restores[i].index = -1; + Restores[i].index = SlotIndex(); } /// handleSpilledImpDefs - Remove IMPLICIT_DEF instructions which are being @@ -1707,8 +1526,14 @@ LiveIntervals::handleSpilledImpDefs(const LiveInterval &li, VirtRegMap &vrm, MachineOperand &O = ri.getOperand(); MachineInstr *MI = &*ri; ++ri; + if (MI->isDebugValue()) { + // Remove debug info for now. + O.setReg(0U); + DEBUG(dbgs() << "Removing debug info due to spill:" << "\t" << *MI); + continue; + } if (O.isDef()) { - assert(MI->getOpcode() == TargetInstrInfo::IMPLICIT_DEF && + assert(MI->isImplicitDef() && "Register def was not rewritten?"); RemoveMachineInstrFromMaps(MI); vrm.RemoveMachineInstrFromMaps(MI); @@ -1723,40 +1548,55 @@ LiveIntervals::handleSpilledImpDefs(const LiveInterval &li, VirtRegMap &vrm, NewLIs.push_back(&getOrCreateInterval(NewVReg)); for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { MachineOperand &MO = MI->getOperand(i); - if (MO.isReg() && MO.getReg() == li.reg) + if (MO.isReg() && MO.getReg() == li.reg) { MO.setReg(NewVReg); + MO.setIsUndef(); + } } } } } -namespace { - struct LISorter { - bool operator()(LiveInterval* A, LiveInterval* B) { - return A->beginNumber() < B->beginNumber(); - } - }; +float +LiveIntervals::getSpillWeight(bool isDef, bool isUse, unsigned loopDepth) { + // Limit the loop depth ridiculousness. + if (loopDepth > 200) + loopDepth = 200; + + // The loop depth is used to roughly estimate the number of times the + // instruction is executed. Something like 10^d is simple, but will quickly + // overflow a float. This expression behaves like 10^d for small d, but is + // more tempered for large d. At d=200 we get 6.7e33 which leaves a bit of + // headroom before overflow. + float lc = powf(1 + (100.0f / (loopDepth+10)), (float)loopDepth); + + return (isDef + isUse) * lc; +} + +void +LiveIntervals::normalizeSpillWeights(std::vector &NewLIs) { + for (unsigned i = 0, e = NewLIs.size(); i != e; ++i) + normalizeSpillWeight(*NewLIs[i]); } std::vector LiveIntervals:: addIntervalsForSpillsFast(const LiveInterval &li, const MachineLoopInfo *loopInfo, - VirtRegMap &vrm, float& SSWeight) { + VirtRegMap &vrm) { unsigned slot = vrm.assignVirt2StackSlot(li.reg); std::vector added; - assert(li.weight != HUGE_VALF && - "attempt to spill already spilled interval!"); + assert(li.isSpillable() && "attempt to spill already spilled interval!"); - DOUT << "\t\t\t\tadding intervals for spills for interval: "; - DEBUG(li.dump()); - DOUT << '\n'; + DEBUG({ + dbgs() << "\t\t\t\tadding intervals for spills for interval: "; + li.dump(); + dbgs() << '\n'; + }); const TargetRegisterClass* rc = mri_->getRegClass(li.reg); - SSWeight = 0.0f; - MachineRegisterInfo::reg_iterator RI = mri_->reg_begin(li.reg); while (RI != mri_->reg_end()) { MachineInstr* MI = &*RI; @@ -1783,10 +1623,7 @@ addIntervalsForSpillsFast(const LiveInterval &li, // create a new register for this spill LiveInterval &nI = getOrCreateInterval(NewVReg); - - // the spill weight is now infinity as it - // cannot be spilled again - nI.weight = HUGE_VALF; + nI.markNotSpillable(); // Rewrite register operands to use the new vreg. for (SmallVectorImpl::iterator I = Indices.begin(), @@ -1798,66 +1635,55 @@ addIntervalsForSpillsFast(const LiveInterval &li, } // Fill in the new live interval. - unsigned index = getInstructionIndex(MI); + SlotIndex index = getInstructionIndex(MI); if (HasUse) { - LiveRange LR(getLoadIndex(index), getUseIndex(index), - nI.getNextValue(~0U, 0, getVNInfoAllocator())); - DOUT << " +" << LR; + LiveRange LR(index.getLoadIndex(), index.getUseIndex(), + nI.getNextValue(SlotIndex(), 0, false, + getVNInfoAllocator())); + DEBUG(dbgs() << " +" << LR); nI.addRange(LR); vrm.addRestorePoint(NewVReg, MI); } if (HasDef) { - LiveRange LR(getDefIndex(index), getStoreIndex(index), - nI.getNextValue(~0U, 0, getVNInfoAllocator())); - DOUT << " +" << LR; + LiveRange LR(index.getDefIndex(), index.getStoreIndex(), + nI.getNextValue(SlotIndex(), 0, false, + getVNInfoAllocator())); + DEBUG(dbgs() << " +" << LR); nI.addRange(LR); vrm.addSpillPoint(NewVReg, true, MI); } added.push_back(&nI); - DOUT << "\t\t\t\tadded new interval: "; - DEBUG(nI.dump()); - DOUT << '\n'; - - unsigned loopDepth = loopInfo->getLoopDepth(MI->getParent()); - if (HasUse) { - if (HasDef) - SSWeight += getSpillWeight(true, true, loopDepth); - else - SSWeight += getSpillWeight(false, true, loopDepth); - } else - SSWeight += getSpillWeight(true, false, loopDepth); + DEBUG({ + dbgs() << "\t\t\t\tadded new interval: "; + nI.dump(); + dbgs() << '\n'; + }); } RI = mri_->reg_begin(li.reg); } - // Clients expect the new intervals to be returned in sorted order. - std::sort(added.begin(), added.end(), LISorter()); - return added; } std::vector LiveIntervals:: addIntervalsForSpills(const LiveInterval &li, SmallVectorImpl &SpillIs, - const MachineLoopInfo *loopInfo, VirtRegMap &vrm, - float &SSWeight) { + const MachineLoopInfo *loopInfo, VirtRegMap &vrm) { if (EnableFastSpilling) - return addIntervalsForSpillsFast(li, loopInfo, vrm, SSWeight); + return addIntervalsForSpillsFast(li, loopInfo, vrm); - assert(li.weight != HUGE_VALF && - "attempt to spill already spilled interval!"); - - DOUT << "\t\t\t\tadding intervals for spills for interval: "; - li.print(DOUT, tri_); - DOUT << '\n'; + assert(li.isSpillable() && "attempt to spill already spilled interval!"); - // Spill slot weight. - SSWeight = 0.0f; + DEBUG({ + dbgs() << "\t\t\t\tadding intervals for spills for interval: "; + li.print(dbgs(), tri_); + dbgs() << '\n'; + }); // Each bit specify whether a spill is required in the MBB. BitVector SpillMBBs(mf_->getNumBlockIDs()); @@ -1883,8 +1709,8 @@ addIntervalsForSpills(const LiveInterval &li, if (vrm.getPreSplitReg(li.reg)) { vrm.setIsSplitFromReg(li.reg, 0); // Unset the split kill marker on the last use. - unsigned KillIdx = vrm.getKillPoint(li.reg); - if (KillIdx) { + SlotIndex KillIdx = vrm.getKillPoint(li.reg); + if (KillIdx != SlotIndex()) { MachineInstr *KillMI = getInstructionFromIndex(KillIdx); assert(KillMI && "Last use disappeared?"); int KillOp = KillMI->findRegisterUseOperandIdx(li.reg, true); @@ -1913,25 +1739,23 @@ addIntervalsForSpills(const LiveInterval &li, Slot, LdSlot, isLoad, isLoadSS, DefIsReMat, false, vrm, rc, ReMatIds, loopInfo, SpillMBBs, SpillIdxes, RestoreMBBs, RestoreIdxes, - MBBVRegsMap, NewLIs, SSWeight); + MBBVRegsMap, NewLIs); } else { rewriteInstructionsForSpills(li, false, I, NULL, 0, Slot, 0, false, false, false, false, vrm, rc, ReMatIds, loopInfo, SpillMBBs, SpillIdxes, RestoreMBBs, RestoreIdxes, - MBBVRegsMap, NewLIs, SSWeight); + MBBVRegsMap, NewLIs); } IsFirstRange = false; } - SSWeight = 0.0f; // Already accounted for when split. handleSpilledImpDefs(li, vrm, rc, NewLIs); + normalizeSpillWeights(NewLIs); return NewLIs; } - bool TrySplit = SplitAtBB && !intervalIsInOneMBB(li); - if (SplitLimit != -1 && (int)numSplits >= SplitLimit) - TrySplit = false; + bool TrySplit = !intervalIsInOneMBB(li); if (TrySplit) ++numSplits; bool NeedStackSlot = false; @@ -1939,23 +1763,22 @@ addIntervalsForSpills(const LiveInterval &li, i != e; ++i) { const VNInfo *VNI = *i; unsigned VN = VNI->id; - unsigned DefIdx = VNI->def; - if (DefIdx == ~1U) + if (VNI->isUnused()) continue; // Dead val#. // Is the def for the val# rematerializable? - MachineInstr *ReMatDefMI = (DefIdx == ~0u) - ? 0 : getInstructionFromIndex(DefIdx); + MachineInstr *ReMatDefMI = VNI->isDefAccurate() + ? getInstructionFromIndex(VNI->def) : 0; bool dummy; if (ReMatDefMI && isReMaterializable(li, VNI, ReMatDefMI, SpillIs, dummy)) { // Remember how to remat the def of this val#. ReMatOrigDefs[VN] = ReMatDefMI; // Original def may be modified so we have to make a copy here. MachineInstr *Clone = mf_->CloneMachineInstr(ReMatDefMI); - ClonedMIs.push_back(Clone); + CloneMIs.push_back(Clone); ReMatDefs[VN] = Clone; bool CanDelete = true; - if (VNI->hasPHIKill) { + if (VNI->hasPHIKill()) { // A kill is a phi node, not all of its uses can be rematerialized. // It must not be deleted. CanDelete = false; @@ -1973,8 +1796,15 @@ addIntervalsForSpills(const LiveInterval &li, } // One stack slot per live interval. - if (NeedStackSlot && vrm.getPreSplitReg(li.reg) == 0) - Slot = vrm.assignVirt2StackSlot(li.reg); + if (NeedStackSlot && vrm.getPreSplitReg(li.reg) == 0) { + if (vrm.getStackSlot(li.reg) == VirtRegMap::NO_STACK_SLOT) + Slot = vrm.assignVirt2StackSlot(li.reg); + + // This case only occurs when the prealloc splitter has already assigned + // a stack slot to this vreg. + else + Slot = vrm.getStackSlot(li.reg); + } // Create new intervals and rewrite defs and uses. for (LiveInterval::Ranges::const_iterator @@ -1991,12 +1821,13 @@ addIntervalsForSpills(const LiveInterval &li, Slot, LdSlot, isLoad, isLoadSS, DefIsReMat, CanDelete, vrm, rc, ReMatIds, loopInfo, SpillMBBs, SpillIdxes, RestoreMBBs, RestoreIdxes, - MBBVRegsMap, NewLIs, SSWeight); + MBBVRegsMap, NewLIs); } // Insert spills / restores if we are splitting. if (!TrySplit) { handleSpilledImpDefs(li, vrm, rc, NewLIs); + normalizeSpillWeights(NewLIs); return NewLIs; } @@ -2005,11 +1836,9 @@ addIntervalsForSpills(const LiveInterval &li, if (NeedStackSlot) { int Id = SpillMBBs.find_first(); while (Id != -1) { - MachineBasicBlock *MBB = mf_->getBlockNumbered(Id); - unsigned loopDepth = loopInfo->getLoopDepth(MBB); std::vector &spills = SpillIdxes[Id]; for (unsigned i = 0, e = spills.size(); i != e; ++i) { - int index = spills[i].index; + SlotIndex index = spills[i].index; unsigned VReg = spills[i].vreg; LiveInterval &nI = getOrCreateInterval(VReg); bool isReMat = vrm.isReMaterialized(VReg); @@ -2047,26 +1876,22 @@ addIntervalsForSpills(const LiveInterval &li, if (FoundUse) { // Also folded uses, do not issue a load. eraseRestoreInfo(Id, index, VReg, RestoreMBBs, RestoreIdxes); - nI.removeRange(getLoadIndex(index), getUseIndex(index)+1); + nI.removeRange(index.getLoadIndex(), index.getDefIndex()); } - nI.removeRange(getDefIndex(index), getStoreIndex(index)); + nI.removeRange(index.getDefIndex(), index.getStoreIndex()); } } // Otherwise tell the spiller to issue a spill. if (!Folded) { LiveRange *LR = &nI.ranges[nI.ranges.size()-1]; - bool isKill = LR->end == getStoreIndex(index); + bool isKill = LR->end == index.getStoreIndex(); if (!MI->registerDefIsDead(nI.reg)) // No need to spill a dead def. vrm.addSpillPoint(VReg, isKill, MI); if (isKill) AddedKill.insert(&nI); } - - // Update spill slot weight. - if (!isReMat) - SSWeight += getSpillWeight(true, false, loopDepth); } Id = SpillMBBs.find_next(Id); } @@ -2074,13 +1899,10 @@ addIntervalsForSpills(const LiveInterval &li, int Id = RestoreMBBs.find_first(); while (Id != -1) { - MachineBasicBlock *MBB = mf_->getBlockNumbered(Id); - unsigned loopDepth = loopInfo->getLoopDepth(MBB); - std::vector &restores = RestoreIdxes[Id]; for (unsigned i = 0, e = restores.size(); i != e; ++i) { - int index = restores[i].index; - if (index == -1) + SlotIndex index = restores[i].index; + if (index == SlotIndex()) continue; unsigned VReg = restores[i].vreg; LiveInterval &nI = getOrCreateInterval(VReg); @@ -2122,11 +1944,10 @@ addIntervalsForSpills(const LiveInterval &li, unsigned ImpUse = getReMatImplicitUse(li, ReMatDefMI); if (ImpUse) { // Re-matting an instruction with virtual register use. Add the - // register as an implicit use on the use MI and update the register - // interval's spill weight to HUGE_VALF to prevent it from being - // spilled. + // register as an implicit use on the use MI and mark the register + // interval as unspillable. LiveInterval &ImpLi = getInterval(ImpUse); - ImpLi.weight = HUGE_VALF; + ImpLi.markNotSpillable(); MI->addOperand(MachineOperand::CreateReg(ImpUse, false, true)); } } @@ -2135,13 +1956,9 @@ addIntervalsForSpills(const LiveInterval &li, // If folding is not possible / failed, then tell the spiller to issue a // load / rematerialization for us. if (Folded) - nI.removeRange(getLoadIndex(index), getUseIndex(index)+1); + nI.removeRange(index.getLoadIndex(), index.getDefIndex()); else vrm.addRestorePoint(VReg, MI); - - // Update spill slot weight. - if (!isReMat) - SSWeight += getSpillWeight(false, true, loopDepth); } Id = RestoreMBBs.find_next(Id); } @@ -2152,10 +1969,10 @@ addIntervalsForSpills(const LiveInterval &li, for (unsigned i = 0, e = NewLIs.size(); i != e; ++i) { LiveInterval *LI = NewLIs[i]; if (!LI->empty()) { - LI->weight /= InstrSlots::NUM * getApproximateInstructionCount(*LI); + LI->weight /= SlotIndex::NUM * getApproximateInstructionCount(*LI); if (!AddedKill.count(LI)) { LiveRange *LR = &LI->ranges[LI->ranges.size()-1]; - unsigned LastUseIdx = getBaseIndex(LR->end); + SlotIndex LastUseIdx = LR->end.getBaseIndex(); MachineInstr *LastUse = getInstructionFromIndex(LastUseIdx); int UseIdx = LastUse->findRegisterUseOperandIdx(LI->reg, false); assert(UseIdx != -1); @@ -2169,6 +1986,7 @@ addIntervalsForSpills(const LiveInterval &li, } handleSpilledImpDefs(li, vrm, rc, RetNewLIs); + normalizeSpillWeights(RetNewLIs); return RetNewLIs; } @@ -2206,7 +2024,9 @@ unsigned LiveIntervals::getNumConflictsWithPhysReg(const LiveInterval &li, E = mri_->reg_end(); I != E; ++I) { MachineOperand &O = I.getOperand(); MachineInstr *MI = O.getParent(); - unsigned Index = getInstructionIndex(MI); + if (MI->isDebugValue()) + continue; + SlotIndex Index = getInstructionIndex(MI); if (pli.liveAt(Index)) ++NumConflicts; } @@ -2214,8 +2034,9 @@ unsigned LiveIntervals::getNumConflictsWithPhysReg(const LiveInterval &li, } /// spillPhysRegAroundRegDefsUses - Spill the specified physical register -/// around all defs and uses of the specified interval. -void LiveIntervals::spillPhysRegAroundRegDefsUses(const LiveInterval &li, +/// around all defs and uses of the specified interval. Return true if it +/// was able to cut its interval. +bool LiveIntervals::spillPhysRegAroundRegDefsUses(const LiveInterval &li, unsigned PhysReg, VirtRegMap &vrm) { unsigned SpillReg = getRepresentativeReg(PhysReg); @@ -2223,56 +2044,80 @@ void LiveIntervals::spillPhysRegAroundRegDefsUses(const LiveInterval &li, // If there are registers which alias PhysReg, but which are not a // sub-register of the chosen representative super register. Assert // since we can't handle it yet. - assert(*AS == SpillReg || !allocatableRegs_[*AS] || + assert(*AS == SpillReg || !allocatableRegs_[*AS] || !hasInterval(*AS) || tri_->isSuperRegister(*AS, SpillReg)); - LiveInterval &pli = getInterval(SpillReg); + bool Cut = false; + SmallVector PRegs; + if (hasInterval(SpillReg)) + PRegs.push_back(SpillReg); + else { + SmallSet Added; + for (const unsigned* AS = tri_->getSubRegisters(SpillReg); *AS; ++AS) + if (Added.insert(*AS) && hasInterval(*AS)) { + PRegs.push_back(*AS); + for (const unsigned* ASS = tri_->getSubRegisters(*AS); *ASS; ++ASS) + Added.insert(*ASS); + } + } + SmallPtrSet SeenMIs; for (MachineRegisterInfo::reg_iterator I = mri_->reg_begin(li.reg), E = mri_->reg_end(); I != E; ++I) { MachineOperand &O = I.getOperand(); MachineInstr *MI = O.getParent(); - if (SeenMIs.count(MI)) + if (MI->isDebugValue() || SeenMIs.count(MI)) continue; SeenMIs.insert(MI); - unsigned Index = getInstructionIndex(MI); - if (pli.liveAt(Index)) { - vrm.addEmergencySpill(SpillReg, MI); - unsigned StartIdx = getLoadIndex(Index); - unsigned EndIdx = getStoreIndex(Index)+1; - if (pli.isInOneLiveRange(StartIdx, EndIdx)) + SlotIndex Index = getInstructionIndex(MI); + for (unsigned i = 0, e = PRegs.size(); i != e; ++i) { + unsigned PReg = PRegs[i]; + LiveInterval &pli = getInterval(PReg); + if (!pli.liveAt(Index)) + continue; + vrm.addEmergencySpill(PReg, MI); + SlotIndex StartIdx = Index.getLoadIndex(); + SlotIndex EndIdx = Index.getNextIndex().getBaseIndex(); + if (pli.isInOneLiveRange(StartIdx, EndIdx)) { pli.removeRange(StartIdx, EndIdx); - else { - cerr << "Ran out of registers during register allocation!\n"; - if (MI->getOpcode() == TargetInstrInfo::INLINEASM) { - cerr << "Please check your inline asm statement for invalid " - << "constraints:\n"; - MI->print(cerr.stream(), tm_); + Cut = true; + } else { + std::string msg; + raw_string_ostream Msg(msg); + Msg << "Ran out of registers during register allocation!"; + if (MI->isInlineAsm()) { + Msg << "\nPlease check your inline asm statement for invalid " + << "constraints:\n"; + MI->print(Msg, tm_); } - exit(1); + llvm_report_error(Msg.str()); } - for (const unsigned* AS = tri_->getSubRegisters(SpillReg); *AS; ++AS) { + for (const unsigned* AS = tri_->getSubRegisters(PReg); *AS; ++AS) { if (!hasInterval(*AS)) continue; LiveInterval &spli = getInterval(*AS); if (spli.liveAt(Index)) - spli.removeRange(getLoadIndex(Index), getStoreIndex(Index)+1); + spli.removeRange(Index.getLoadIndex(), + Index.getNextIndex().getBaseIndex()); } } } + return Cut; } LiveRange LiveIntervals::addLiveRangeToEndOfBlock(unsigned reg, - MachineInstr* startInst) { + MachineInstr* startInst) { LiveInterval& Interval = getOrCreateInterval(reg); VNInfo* VN = Interval.getNextValue( - getInstructionIndex(startInst) + InstrSlots::DEF, - startInst, getVNInfoAllocator()); - VN->hasPHIKill = true; - VN->kills.push_back(getMBBEndIdx(startInst->getParent())); - LiveRange LR(getInstructionIndex(startInst) + InstrSlots::DEF, - getMBBEndIdx(startInst->getParent()) + 1, VN); + SlotIndex(getInstructionIndex(startInst).getDefIndex()), + startInst, true, getVNInfoAllocator()); + VN->setHasPHIKill(true); + VN->kills.push_back(indexes_->getTerminatorGap(startInst->getParent())); + LiveRange LR( + SlotIndex(getInstructionIndex(startInst).getDefIndex()), + getMBBEndIdx(startInst->getParent()), VN); Interval.addRange(LR); return LR; } +