X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FLiveIntervalAnalysis.cpp;h=3563f8eab0237005ae23edbaffd93bbf0d7c6285;hb=f6e00376e7dc6d84f53efaf7cef9089021fac609;hp=18abe41174b5eab287189f004d215f50f135a6d4;hpb=e25dde550baec1f79caf2fc06edd74e7ae6ffa33;p=oota-llvm.git diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp index 18abe41174b..3563f8eab02 100644 --- a/lib/CodeGen/LiveIntervalAnalysis.cpp +++ b/lib/CodeGen/LiveIntervalAnalysis.cpp @@ -15,13 +15,13 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "regalloc" #include "llvm/CodeGen/LiveIntervalAnalysis.h" #include "LiveRangeCalc.h" #include "llvm/ADT/DenseSet.h" #include "llvm/ADT/STLExtras.h" #include "llvm/Analysis/AliasAnalysis.h" #include "llvm/CodeGen/LiveVariables.h" +#include "llvm/CodeGen/MachineBlockFrequencyInfo.h" #include "llvm/CodeGen/MachineDominators.h" #include "llvm/CodeGen/MachineInstr.h" #include "llvm/CodeGen/MachineRegisterInfo.h" @@ -41,6 +41,8 @@ #include using namespace llvm; +#define DEBUG_TYPE "regalloc" + char LiveIntervals::ID = 0; char &llvm::LiveIntervalsID = LiveIntervals::ID; INITIALIZE_PASS_BEGIN(LiveIntervals, "liveintervals", @@ -78,7 +80,7 @@ void LiveIntervals::getAnalysisUsage(AnalysisUsage &AU) const { } LiveIntervals::LiveIntervals() : MachineFunctionPass(ID), - DomTree(0), LRCalc(0) { + DomTree(nullptr), LRCalc(nullptr) { initializeLiveIntervalsPass(*PassRegistry::getPassRegistry()); } @@ -95,9 +97,9 @@ void LiveIntervals::releaseMemory() { RegMaskBits.clear(); RegMaskBlocks.clear(); - for (unsigned i = 0, e = RegUnitIntervals.size(); i != e; ++i) - delete RegUnitIntervals[i]; - RegUnitIntervals.clear(); + for (unsigned i = 0, e = RegUnitRanges.size(); i != e; ++i) + delete RegUnitRanges[i]; + RegUnitRanges.clear(); // Release VNInfo memory regions, VNInfo objects don't need to be dtor'd. VNInfoAllocator.Reset(); @@ -139,15 +141,15 @@ void LiveIntervals::print(raw_ostream &OS, const Module* ) const { OS << "********** INTERVALS **********\n"; // Dump the regunits. - for (unsigned i = 0, e = RegUnitIntervals.size(); i != e; ++i) - if (LiveInterval *LI = RegUnitIntervals[i]) - OS << PrintRegUnit(i, TRI) << " = " << *LI << '\n'; + for (unsigned i = 0, e = RegUnitRanges.size(); i != e; ++i) + if (LiveRange *LR = RegUnitRanges[i]) + OS << PrintRegUnit(i, TRI) << ' ' << *LR << '\n'; // Dump the virtregs. for (unsigned i = 0, e = MRI->getNumVirtRegs(); i != e; ++i) { unsigned Reg = TargetRegisterInfo::index2VirtReg(i); if (hasInterval(Reg)) - OS << PrintReg(Reg) << " = " << getInterval(Reg) << '\n'; + OS << getInterval(Reg) << '\n'; } OS << "RegMasks:"; @@ -170,7 +172,8 @@ void LiveIntervals::dumpInstrs() const { #endif LiveInterval* LiveIntervals::createInterval(unsigned reg) { - float Weight = TargetRegisterInfo::isPhysicalRegister(reg) ? HUGE_VALF : 0.0F; + float Weight = TargetRegisterInfo::isPhysicalRegister(reg) ? + llvm::huge_valf : 0.0F; return new LiveInterval(reg, Weight); } @@ -227,12 +230,10 @@ void LiveIntervals::computeRegMasks() { // interference. // -/// computeRegUnitInterval - Compute the live interval of a register unit, based -/// on the uses and defs of aliasing registers. The interval should be empty, +/// computeRegUnitInterval - Compute the live range of a register unit, based +/// on the uses and defs of aliasing registers. The range should be empty, /// or contain only dead phi-defs from ABI blocks. -void LiveIntervals::computeRegUnitInterval(LiveInterval &LI) { - unsigned Unit = LI.reg; - +void LiveIntervals::computeRegUnitRange(LiveRange &LR, unsigned Unit) { assert(LRCalc && "LRCalc not initialized."); LRCalc->reset(MF, getSlotIndexes(), DomTree, &getVNInfoAllocator()); @@ -245,18 +246,18 @@ void LiveIntervals::computeRegUnitInterval(LiveInterval &LI) { for (MCSuperRegIterator Supers(*Roots, TRI, /*IncludeSelf=*/true); Supers.isValid(); ++Supers) { if (!MRI->reg_empty(*Supers)) - LRCalc->createDeadDefs(LI, *Supers); + LRCalc->createDeadDefs(LR, *Supers); } } - // Now extend LI to reach all uses. + // Now extend LR to reach all uses. // Ignore uses of reserved registers. We only track defs of those. for (MCRegUnitRootIterator Roots(Unit, TRI); Roots.isValid(); ++Roots) { for (MCSuperRegIterator Supers(*Roots, TRI, /*IncludeSelf=*/true); Supers.isValid(); ++Supers) { unsigned Reg = *Supers; if (!MRI->isReserved(Reg) && !MRI->reg_empty(Reg)) - LRCalc->extendToUses(LI, Reg); + LRCalc->extendToUses(LR, Reg); } } } @@ -267,11 +268,11 @@ void LiveIntervals::computeRegUnitInterval(LiveInterval &LI) { /// without a corresponding def when entering the entry block or a landing pad. /// void LiveIntervals::computeLiveInRegUnits() { - RegUnitIntervals.resize(TRI->getNumRegUnits()); + RegUnitRanges.resize(TRI->getNumRegUnits()); DEBUG(dbgs() << "Computing live-in reg-units in ABI blocks.\n"); - // Keep track of the intervals allocated. - SmallVector NewIntvs; + // Keep track of the live range sets allocated. + SmallVector NewRanges; // Check all basic blocks for live-ins. for (MachineFunction::const_iterator MFI = MF->begin(), MFE = MF->end(); @@ -289,23 +290,25 @@ void LiveIntervals::computeLiveInRegUnits() { LIE = MBB->livein_end(); LII != LIE; ++LII) { for (MCRegUnitIterator Units(*LII, TRI); Units.isValid(); ++Units) { unsigned Unit = *Units; - LiveInterval *Intv = RegUnitIntervals[Unit]; - if (!Intv) { - Intv = RegUnitIntervals[Unit] = new LiveInterval(Unit, HUGE_VALF); - NewIntvs.push_back(Intv); + LiveRange *LR = RegUnitRanges[Unit]; + if (!LR) { + LR = RegUnitRanges[Unit] = new LiveRange(); + NewRanges.push_back(Unit); } - VNInfo *VNI = Intv->createDeadDef(Begin, getVNInfoAllocator()); + VNInfo *VNI = LR->createDeadDef(Begin, getVNInfoAllocator()); (void)VNI; DEBUG(dbgs() << ' ' << PrintRegUnit(Unit, TRI) << '#' << VNI->id); } } DEBUG(dbgs() << '\n'); } - DEBUG(dbgs() << "Created " << NewIntvs.size() << " new intervals.\n"); + DEBUG(dbgs() << "Created " << NewRanges.size() << " new intervals.\n"); - // Compute the 'normal' part of the intervals. - for (unsigned i = 0, e = NewIntvs.size(); i != e; ++i) - computeRegUnitInterval(*NewIntvs[i]); + // Compute the 'normal' part of the ranges. + for (unsigned i = 0, e = NewRanges.size(); i != e; ++i) { + unsigned Unit = NewRanges[i]; + computeRegUnitRange(*RegUnitRanges[Unit], Unit); + } } @@ -324,8 +327,10 @@ bool LiveIntervals::shrinkToUses(LiveInterval *li, SmallPtrSet LiveOut; // Visit all instructions reading li->reg. - for (MachineRegisterInfo::reg_iterator I = MRI->reg_begin(li->reg); - MachineInstr *UseMI = I.skipInstruction();) { + for (MachineRegisterInfo::reg_instr_iterator + I = MRI->reg_instr_begin(li->reg), E = MRI->reg_instr_end(); + I != E; ) { + MachineInstr *UseMI = &*(I++); if (UseMI->isDebugValue() || !UseMI->readsVirtualRegister(li->reg)) continue; SlotIndex Idx = getInstructionIndex(UseMI).getRegSlot(); @@ -457,7 +462,7 @@ void LiveIntervals::pruneValue(LiveInterval *LI, SlotIndex Kill, MachineBasicBlock *KillMBB = Indexes->getMBBFromIndex(Kill); SlotIndex MBBStart, MBBEnd; - tie(MBBStart, MBBEnd) = Indexes->getMBBRange(KillMBB); + std::tie(MBBStart, MBBEnd) = Indexes->getMBBRange(KillMBB); // If VNI isn't live out from KillMBB, the value is trivially pruned. if (LRQ.endPoint() < MBBEnd) { @@ -484,7 +489,7 @@ void LiveIntervals::pruneValue(LiveInterval *LI, SlotIndex Kill, MachineBasicBlock *MBB = *I; // Check if VNI is live in to MBB. - tie(MBBStart, MBBEnd) = Indexes->getMBBRange(MBB); + std::tie(MBBStart, MBBEnd) = Indexes->getMBBRange(MBB); LiveQueryResult LRQ = LI->Query(MBBStart); if (LRQ.valueIn() != VNI) { // This block isn't part of the VNI segment. Prune the search. @@ -514,7 +519,7 @@ void LiveIntervals::pruneValue(LiveInterval *LI, SlotIndex Kill, void LiveIntervals::addKillFlags(const VirtRegMap *VRM) { // Keep track of regunit ranges. - SmallVector, 8> RU; + SmallVector, 8> RU; for (unsigned i = 0, e = MRI->getNumVirtRegs(); i != e; ++i) { unsigned Reg = TargetRegisterInfo::index2VirtReg(i); @@ -529,10 +534,10 @@ void LiveIntervals::addKillFlags(const VirtRegMap *VRM) { RU.clear(); for (MCRegUnitIterator Units(VRM->getPhys(Reg), TRI); Units.isValid(); ++Units) { - LiveInterval *RUInt = &getRegUnit(*Units); - if (RUInt->empty()) + LiveRange &RURanges = getRegUnit(*Units); + if (RURanges.empty()) continue; - RU.push_back(std::make_pair(RUInt, RUInt->find(LI->begin()->end))); + RU.push_back(std::make_pair(&RURanges, RURanges.find(LI->begin()->end))); } // Every instruction that kills Reg corresponds to a segment range end @@ -556,21 +561,21 @@ void LiveIntervals::addKillFlags(const VirtRegMap *VRM) { // There should be no kill flag on FOO when %vreg5 is rewritten as %EAX. bool CancelKill = false; for (unsigned u = 0, e = RU.size(); u != e; ++u) { - LiveInterval *RInt = RU[u].first; - LiveInterval::iterator &I = RU[u].second; - if (I == RInt->end()) + LiveRange &RRanges = *RU[u].first; + LiveRange::iterator &I = RU[u].second; + if (I == RRanges.end()) continue; - I = RInt->advanceTo(I, RI->end); - if (I == RInt->end() || I->start >= RI->end) + I = RRanges.advanceTo(I, RI->end); + if (I == RRanges.end() || I->start >= RI->end) continue; // I is overlapping RI. CancelKill = true; break; } if (CancelKill) - MI->clearRegisterKills(Reg, NULL); + MI->clearRegisterKills(Reg, nullptr); else - MI->addRegisterKilled(Reg, NULL); + MI->addRegisterKilled(Reg, nullptr); } } } @@ -586,17 +591,17 @@ LiveIntervals::intervalIsInOneMBB(const LiveInterval &LI) const { SlotIndex Start = LI.beginIndex(); if (Start.isBlock()) - return NULL; + return nullptr; SlotIndex Stop = LI.endIndex(); if (Stop.isBlock()) - return NULL; + return nullptr; // getMBBFromIndex doesn't need to search the MBB table when both indexes // belong to proper instructions. MachineBasicBlock *MBB1 = Indexes->getMBBFromIndex(Start); MachineBasicBlock *MBB2 = Indexes->getMBBFromIndex(Stop); - return MBB1 == MBB2 ? MBB1 : NULL; + return MBB1 == MBB2 ? MBB1 : nullptr; } bool @@ -619,9 +624,12 @@ LiveIntervals::hasPHIKill(const LiveInterval &LI, const VNInfo *VNI) const { } float -LiveIntervals::getSpillWeight(bool isDef, bool isUse, BlockFrequency freq) { - const float Scale = 1.0f / BlockFrequency::getEntryFrequency(); - return (isDef + isUse) * (freq.getFrequency() * Scale); +LiveIntervals::getSpillWeight(bool isDef, bool isUse, + const MachineBlockFrequencyInfo *MBFI, + const MachineInstr *MI) { + BlockFrequency Freq = MBFI->getBlockFreq(MI->getParent()); + const float Scale = 1.0f / MBFI->getEntryFreq(); + return (isDef + isUse) * (Freq.getFrequency() * Scale); } LiveRange::Segment @@ -710,7 +718,7 @@ private: const TargetRegisterInfo& TRI; SlotIndex OldIdx; SlotIndex NewIdx; - SmallPtrSet Updated; + SmallPtrSet Updated; bool UpdateFlags; public: @@ -724,7 +732,7 @@ public: // physregs, even those that aren't needed for regalloc, in order to update // kill flags. This is wasteful. Eventually, LiveVariables will strip all kill // flags, and postRA passes will use a live register utility instead. - LiveInterval *getRegUnitLI(unsigned Unit) { + LiveRange *getRegUnitLI(unsigned Unit) { if (UpdateFlags) return &LIS.getRegUnit(Unit); return LIS.getCachedRegUnit(Unit); @@ -749,15 +757,16 @@ public: if (!Reg) continue; if (TargetRegisterInfo::isVirtualRegister(Reg)) { - updateRange(LIS.getInterval(Reg)); + LiveInterval &LI = LIS.getInterval(Reg); + updateRange(LI, Reg); continue; } // For physregs, only update the regunits that actually have a // precomputed live range. for (MCRegUnitIterator Units(Reg, &TRI); Units.isValid(); ++Units) - if (LiveInterval *LI = getRegUnitLI(*Units)) - updateRange(*LI); + if (LiveRange *LR = getRegUnitLI(*Units)) + updateRange(*LR, *Units); } if (hasRegMask) updateRegMaskSlots(); @@ -766,26 +775,26 @@ public: private: /// Update a single live range, assuming an instruction has been moved from /// OldIdx to NewIdx. - void updateRange(LiveInterval &LI) { - if (!Updated.insert(&LI)) + void updateRange(LiveRange &LR, unsigned Reg) { + if (!Updated.insert(&LR)) return; DEBUG({ dbgs() << " "; - if (TargetRegisterInfo::isVirtualRegister(LI.reg)) - dbgs() << PrintReg(LI.reg); + if (TargetRegisterInfo::isVirtualRegister(Reg)) + dbgs() << PrintReg(Reg); else - dbgs() << PrintRegUnit(LI.reg, &TRI); - dbgs() << ":\t" << LI << '\n'; + dbgs() << PrintRegUnit(Reg, &TRI); + dbgs() << ":\t" << LR << '\n'; }); if (SlotIndex::isEarlierInstr(OldIdx, NewIdx)) - handleMoveDown(LI); + handleMoveDown(LR); else - handleMoveUp(LI); - DEBUG(dbgs() << " -->\t" << LI << '\n'); - LI.verify(); + handleMoveUp(LR, Reg); + DEBUG(dbgs() << " -->\t" << LR << '\n'); + LR.verify(); } - /// Update LI to reflect an instruction has been moved downwards from OldIdx + /// Update LR to reflect an instruction has been moved downwards from OldIdx /// to NewIdx. /// /// 1. Live def at OldIdx: @@ -805,11 +814,11 @@ private: /// 5. Value read at OldIdx, killed before NewIdx: /// Extend kill to NewIdx. /// - void handleMoveDown(LiveInterval &LI) { + void handleMoveDown(LiveRange &LR) { // First look for a kill at OldIdx. - LiveInterval::iterator I = LI.find(OldIdx.getBaseIndex()); - LiveInterval::iterator E = LI.end(); - // Is LI even live at OldIdx? + LiveRange::iterator I = LR.find(OldIdx.getBaseIndex()); + LiveRange::iterator E = LR.end(); + // Is LR even live at OldIdx? if (I == E || SlotIndex::isEarlierInstr(OldIdx, I->start)) return; @@ -826,7 +835,7 @@ private: for (MIBundleOperands MO(KillMI); MO.isValid(); ++MO) if (MO->isReg() && MO->isUse()) MO->setIsKill(false); - // Adjust I->end to reach NewIdx. This may temporarily make LI invalid by + // Adjust I->end to reach NewIdx. This may temporarily make LR invalid by // overlapping ranges. Case 5 above. I->end = NewIdx.getRegSlot(I->end.isEarlyClobber()); // If this was a kill, there may also be a def. Otherwise we're done. @@ -855,25 +864,25 @@ private: assert((I->end == OldIdx.getDeadSlot() || SlotIndex::isSameInstr(I->end, NewIdx)) && "Cannot move def below kill"); - LiveInterval::iterator NewI = LI.advanceTo(I, NewIdx.getRegSlot()); + LiveRange::iterator NewI = LR.advanceTo(I, NewIdx.getRegSlot()); if (NewI != E && SlotIndex::isSameInstr(NewI->start, NewIdx)) { // There is an existing def at NewIdx, case 4 above. The def at OldIdx is // coalesced into that value. assert(NewI->valno != DefVNI && "Multiple defs of value?"); - LI.removeValNo(DefVNI); + LR.removeValNo(DefVNI); return; } // There was no existing def at NewIdx. Turn *I into a dead def at NewIdx. - // If the def at OldIdx was dead, we allow it to be moved across other LI + // If the def at OldIdx was dead, we allow it to be moved across other LR // values. The new range should be placed immediately before NewI, move any // intermediate ranges up. assert(NewI != I && "Inconsistent iterators"); - std::copy(llvm::next(I), NewI, I); - *llvm::prior(NewI) + std::copy(std::next(I), NewI, I); + *std::prev(NewI) = LiveRange::Segment(DefVNI->def, NewIdx.getDeadSlot(), DefVNI); } - /// Update LI to reflect an instruction has been moved upwards from OldIdx + /// Update LR to reflect an instruction has been moved upwards from OldIdx /// to NewIdx. /// /// 1. Live def at OldIdx: @@ -893,11 +902,11 @@ private: /// Hoist kill to NewIdx, then scan for last kill between NewIdx and /// OldIdx. /// - void handleMoveUp(LiveInterval &LI) { + void handleMoveUp(LiveRange &LR, unsigned Reg) { // First look for a kill at OldIdx. - LiveInterval::iterator I = LI.find(OldIdx.getBaseIndex()); - LiveInterval::iterator E = LI.end(); - // Is LI even live at OldIdx? + LiveRange::iterator I = LR.find(OldIdx.getBaseIndex()); + LiveRange::iterator E = LR.end(); + // Is LR even live at OldIdx? if (I == E || SlotIndex::isEarlierInstr(OldIdx, I->start)) return; @@ -914,7 +923,7 @@ private: if (I == E || !SlotIndex::isSameInstr(I->start, OldIdx)) { // No def, search for the new kill. // This can never be an early clobber kill since there is no def. - llvm::prior(I)->end = findLastUseBefore(LI.reg).getRegSlot(); + std::prev(I)->end = findLastUseBefore(Reg).getRegSlot(); return; } } @@ -926,18 +935,18 @@ private: DefVNI->def = NewIdx.getRegSlot(I->start.isEarlyClobber()); // Check for an existing def at NewIdx. - LiveInterval::iterator NewI = LI.find(NewIdx.getRegSlot()); + LiveRange::iterator NewI = LR.find(NewIdx.getRegSlot()); if (SlotIndex::isSameInstr(NewI->start, NewIdx)) { assert(NewI->valno != DefVNI && "Same value defined more than once?"); // There is an existing def at NewIdx. if (I->end.isDead()) { // Case 3: Remove the dead def at OldIdx. - LI.removeValNo(DefVNI); + LR.removeValNo(DefVNI); return; } // Case 4: Replace def at NewIdx with live def at OldIdx. I->start = DefVNI->def; - LI.removeValNo(NewI->valno); + LR.removeValNo(NewI->valno); return; } @@ -948,9 +957,9 @@ private: return; } - // DefVNI is a dead def. It may have been moved across other values in LI, + // DefVNI is a dead def. It may have been moved across other values in LR, // so move I up to NewI. Slide [NewI;I) down one position. - std::copy_backward(NewI, I, llvm::next(I)); + std::copy_backward(NewI, I, std::next(I)); *NewI = LiveRange::Segment(DefVNI->def, NewIdx.getDeadSlot(), DefVNI); } @@ -962,11 +971,11 @@ private: "No RegMask at OldIdx."); *RI = NewIdx.getRegSlot(); assert((RI == LIS.RegMaskSlots.begin() || - SlotIndex::isEarlierInstr(*llvm::prior(RI), *RI)) && - "Cannot move regmask instruction above another call"); - assert((llvm::next(RI) == LIS.RegMaskSlots.end() || - SlotIndex::isEarlierInstr(*RI, *llvm::next(RI))) && - "Cannot move regmask instruction below another call"); + SlotIndex::isEarlierInstr(*std::prev(RI), *RI)) && + "Cannot move regmask instruction above another call"); + assert((std::next(RI) == LIS.RegMaskSlots.end() || + SlotIndex::isEarlierInstr(*RI, *std::next(RI))) && + "Cannot move regmask instruction below another call"); } // Return the last use of reg between NewIdx and OldIdx. @@ -974,10 +983,10 @@ private: if (TargetRegisterInfo::isVirtualRegister(Reg)) { SlotIndex LastUse = NewIdx; - for (MachineRegisterInfo::use_nodbg_iterator - UI = MRI.use_nodbg_begin(Reg), - UE = MRI.use_nodbg_end(); - UI != UE; UI.skipInstruction()) { + for (MachineRegisterInfo::use_instr_nodbg_iterator + UI = MRI.use_instr_nodbg_begin(Reg), + UE = MRI.use_instr_nodbg_end(); + UI != UE; ++UI) { const MachineInstr* MI = &*UI; SlotIndex InstSlot = LIS.getSlotIndexes()->getInstructionIndex(MI); if (InstSlot > LastUse && InstSlot < OldIdx) @@ -1119,7 +1128,7 @@ LiveIntervals::repairIntervalsInRange(MachineBasicBlock *MBB, if (LII->end.isDead()) { SlotIndex prevStart; if (LII != LI.begin()) - prevStart = llvm::prior(LII)->start; + prevStart = std::prev(LII)->start; // FIXME: This could be more efficient if there was a // removeSegment method that returned an iterator.