//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "spiller"
-
#include "Spiller.h"
-#include "VirtRegMap.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
+#include "llvm/CodeGen/LiveRangeEdit.h"
+#include "llvm/CodeGen/LiveStackAnalysis.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineLoopInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/CodeGen/VirtRegMap.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
-#include <set>
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetMachine.h"
using namespace llvm;
+#define DEBUG_TYPE "spiller"
+
namespace {
- enum SpillerName { trivial, standard, splitting };
+ enum SpillerName { trivial, inline_ };
}
static cl::opt<SpillerName>
cl::desc("Spiller to use: (default: standard)"),
cl::Prefix,
cl::values(clEnumVal(trivial, "trivial spiller"),
- clEnumVal(standard, "default spiller"),
- clEnumVal(splitting, "splitting spiller"),
+ clEnumValN(inline_, "inline", "inline spiller"),
clEnumValEnd),
- cl::init(standard));
+ cl::init(trivial));
// Spiller virtual destructor implementation.
Spiller::~Spiller() {}
/// Utility class for spillers.
class SpillerBase : public Spiller {
protected:
-
+ MachineFunctionPass *pass;
MachineFunction *mf;
+ VirtRegMap *vrm;
LiveIntervals *lis;
MachineFrameInfo *mfi;
MachineRegisterInfo *mri;
const TargetInstrInfo *tii;
- VirtRegMap *vrm;
-
- /// Construct a spiller base.
- SpillerBase(MachineFunction *mf, LiveIntervals *lis, VirtRegMap *vrm)
- : mf(mf), lis(lis), vrm(vrm)
+ const TargetRegisterInfo *tri;
+
+ /// Construct a spiller base.
+ SpillerBase(MachineFunctionPass &pass, MachineFunction &mf, VirtRegMap &vrm)
+ : pass(&pass), mf(&mf), vrm(&vrm)
{
- mfi = mf->getFrameInfo();
- mri = &mf->getRegInfo();
- tii = mf->getTarget().getInstrInfo();
+ lis = &pass.getAnalysis<LiveIntervals>();
+ mfi = mf.getFrameInfo();
+ mri = &mf.getRegInfo();
+ tii = mf.getSubtarget().getInstrInfo();
+ tri = mf.getSubtarget().getRegisterInfo();
}
/// Add spill ranges for every use/def of the live interval, inserting loads
/// immediately before each use, and stores after each def. No folding or
/// remat is attempted.
- std::vector<LiveInterval*> trivialSpillEverywhere(LiveInterval *li) {
- DEBUG(errs() << "Spilling everywhere " << *li << "\n");
+ void trivialSpillEverywhere(LiveRangeEdit& LRE) {
+ LiveInterval* li = &LRE.getParent();
+
+ DEBUG(dbgs() << "Spilling everywhere " << *li << "\n");
- assert(li->weight != HUGE_VALF &&
+ assert(li->weight != llvm::huge_valf &&
"Attempting to spill already spilled value.");
- assert(!li->isStackSlot() &&
+ assert(!TargetRegisterInfo::isStackSlot(li->reg) &&
"Trying to spill a stack slot.");
- DEBUG(errs() << "Trivial spill everywhere of reg" << li->reg << "\n");
+ DEBUG(dbgs() << "Trivial spill everywhere of reg" << li->reg << "\n");
- std::vector<LiveInterval*> added;
-
const TargetRegisterClass *trc = mri->getRegClass(li->reg);
unsigned ss = vrm->assignVirt2StackSlot(li->reg);
// Iterate over reg uses/defs.
- for (MachineRegisterInfo::reg_iterator
- regItr = mri->reg_begin(li->reg); regItr != mri->reg_end();) {
+ for (MachineRegisterInfo::reg_instr_iterator
+ regItr = mri->reg_instr_begin(li->reg);
+ regItr != mri->reg_instr_end();) {
// Grab the use/def instr.
MachineInstr *mi = &*regItr;
- DEBUG(errs() << " Processing " << *mi);
+ DEBUG(dbgs() << " Processing " << *mi);
// Step regItr to the next use/def instr.
- do {
- ++regItr;
- } while (regItr != mri->reg_end() && (&*regItr == mi));
-
+ ++regItr;
+
// Collect uses & defs for this instr.
SmallVector<unsigned, 2> indices;
bool hasUse = false;
indices.push_back(i);
}
- // Create a new vreg & interval for this instr.
- unsigned newVReg = mri->createVirtualRegister(trc);
- vrm->grow();
- vrm->assignVirt2StackSlot(newVReg, ss);
- LiveInterval *newLI = &lis->getOrCreateInterval(newVReg);
- newLI->weight = HUGE_VALF;
-
+ // Create a new virtual register for the load and/or store.
+ unsigned NewVReg = LRE.create();
+
// Update the reg operands & kill flags.
for (unsigned i = 0; i < indices.size(); ++i) {
unsigned mopIdx = indices[i];
MachineOperand &mop = mi->getOperand(mopIdx);
- mop.setReg(newVReg);
+ mop.setReg(NewVReg);
if (mop.isUse() && !mi->isRegTiedToDefOperand(mopIdx)) {
mop.setIsKill(true);
}
// Insert reload if necessary.
MachineBasicBlock::iterator miItr(mi);
if (hasUse) {
- tii->loadRegFromStackSlot(*mi->getParent(), miItr, newVReg, ss, trc);
- MachineInstr *loadInstr(prior(miItr));
- SlotIndex loadIndex =
- lis->InsertMachineInstrInMaps(loadInstr).getDefIndex();
- SlotIndex endIndex = loadIndex.getNextIndex();
- VNInfo *loadVNI =
- newLI->getNextValue(loadIndex, 0, true, lis->getVNInfoAllocator());
- loadVNI->addKill(endIndex);
- newLI->addRange(LiveRange(loadIndex, endIndex, loadVNI));
+ MachineInstrSpan MIS(miItr);
+
+ tii->loadRegFromStackSlot(*mi->getParent(), miItr, NewVReg, ss, trc,
+ tri);
+ lis->InsertMachineInstrRangeInMaps(MIS.begin(), miItr);
}
// Insert store if necessary.
if (hasDef) {
- tii->storeRegToStackSlot(*mi->getParent(), llvm::next(miItr), newVReg, true,
- ss, trc);
- MachineInstr *storeInstr(llvm::next(miItr));
- SlotIndex storeIndex =
- lis->InsertMachineInstrInMaps(storeInstr).getDefIndex();
- SlotIndex beginIndex = storeIndex.getPrevIndex();
- VNInfo *storeVNI =
- newLI->getNextValue(beginIndex, 0, true, lis->getVNInfoAllocator());
- storeVNI->addKill(storeIndex);
- newLI->addRange(LiveRange(beginIndex, storeIndex, storeVNI));
- }
+ MachineInstrSpan MIS(miItr);
- added.push_back(newLI);
+ tii->storeRegToStackSlot(*mi->getParent(), std::next(miItr), NewVReg,
+ true, ss, trc, tri);
+ lis->InsertMachineInstrRangeInMaps(std::next(miItr), MIS.end());
+ }
}
-
- return added;
}
-
};
+} // end anonymous namespace
+
+namespace {
/// Spills any live range using the spill-everywhere method with no attempt at
/// folding.
class TrivialSpiller : public SpillerBase {
public:
- TrivialSpiller(MachineFunction *mf, LiveIntervals *lis, VirtRegMap *vrm)
- : SpillerBase(mf, lis, vrm) {}
+ TrivialSpiller(MachineFunctionPass &pass, MachineFunction &mf,
+ VirtRegMap &vrm)
+ : SpillerBase(pass, mf, vrm) {}
- std::vector<LiveInterval*> spill(LiveInterval *li,
- SmallVectorImpl<LiveInterval*> &spillIs,
- SlotIndex*) {
+ void spill(LiveRangeEdit &LRE) override {
// Ignore spillIs - we don't use it.
- return trivialSpillEverywhere(li);
- }
-
-};
-
-/// Falls back on LiveIntervals::addIntervalsForSpills.
-class StandardSpiller : public Spiller {
-protected:
- LiveIntervals *lis;
- const MachineLoopInfo *loopInfo;
- VirtRegMap *vrm;
-public:
- StandardSpiller(LiveIntervals *lis, const MachineLoopInfo *loopInfo,
- VirtRegMap *vrm)
- : lis(lis), loopInfo(loopInfo), vrm(vrm) {}
-
- /// Falls back on LiveIntervals::addIntervalsForSpills.
- std::vector<LiveInterval*> spill(LiveInterval *li,
- SmallVectorImpl<LiveInterval*> &spillIs,
- SlotIndex*) {
- return lis->addIntervalsForSpills(*li, spillIs, loopInfo, *vrm);
+ trivialSpillEverywhere(LRE);
}
-
};
-/// When a call to spill is placed this spiller will first try to break the
-/// interval up into its component values (one new interval per value).
-/// If this fails, or if a call is placed to spill a previously split interval
-/// then the spiller falls back on the standard spilling mechanism.
-class SplittingSpiller : public StandardSpiller {
-public:
- SplittingSpiller(MachineFunction *mf, LiveIntervals *lis,
- const MachineLoopInfo *loopInfo, VirtRegMap *vrm)
- : StandardSpiller(lis, loopInfo, vrm) {
-
- mri = &mf->getRegInfo();
- tii = mf->getTarget().getInstrInfo();
- tri = mf->getTarget().getRegisterInfo();
- }
-
- std::vector<LiveInterval*> spill(LiveInterval *li,
- SmallVectorImpl<LiveInterval*> &spillIs,
- SlotIndex *earliestStart) {
-
- if (worthTryingToSplit(li)) {
- return tryVNISplit(li, earliestStart);
- }
- // else
- return StandardSpiller::spill(li, spillIs, earliestStart);
- }
-
-private:
-
- MachineRegisterInfo *mri;
- const TargetInstrInfo *tii;
- const TargetRegisterInfo *tri;
- DenseSet<LiveInterval*> alreadySplit;
+} // end anonymous namespace
- bool worthTryingToSplit(LiveInterval *li) const {
- return (!alreadySplit.count(li) && li->getNumValNums() > 1);
- }
-
- /// Try to break a LiveInterval into its component values.
- std::vector<LiveInterval*> tryVNISplit(LiveInterval *li,
- SlotIndex *earliestStart) {
-
- DEBUG(errs() << "Trying VNI split of %reg" << *li << "\n");
-
- std::vector<LiveInterval*> added;
- SmallVector<VNInfo*, 4> vnis;
-
- std::copy(li->vni_begin(), li->vni_end(), std::back_inserter(vnis));
-
- for (SmallVectorImpl<VNInfo*>::iterator vniItr = vnis.begin(),
- vniEnd = vnis.end(); vniItr != vniEnd; ++vniItr) {
- VNInfo *vni = *vniItr;
-
- // Skip unused VNIs, or VNIs with no kills.
- if (vni->isUnused() || vni->kills.empty())
- continue;
-
- DEBUG(errs() << " Extracted Val #" << vni->id << " as ");
- LiveInterval *splitInterval = extractVNI(li, vni);
-
- if (splitInterval != 0) {
- DEBUG(errs() << *splitInterval << "\n");
- added.push_back(splitInterval);
- alreadySplit.insert(splitInterval);
- if (earliestStart != 0) {
- if (splitInterval->beginIndex() < *earliestStart)
- *earliestStart = splitInterval->beginIndex();
- }
- } else {
- DEBUG(errs() << "0\n");
- }
- }
-
- DEBUG(errs() << "Original LI: " << *li << "\n");
-
- // If there original interval still contains some live ranges
- // add it to added and alreadySplit.
- if (!li->empty()) {
- added.push_back(li);
- alreadySplit.insert(li);
- if (earliestStart != 0) {
- if (li->beginIndex() < *earliestStart)
- *earliestStart = li->beginIndex();
- }
- }
-
- return added;
- }
-
- /// Extract the given value number from the interval.
- LiveInterval* extractVNI(LiveInterval *li, VNInfo *vni) const {
- assert(vni->isDefAccurate() || vni->isPHIDef());
- assert(!vni->kills.empty());
-
- // Create a new vreg and live interval, copy VNI kills & ranges over.
- const TargetRegisterClass *trc = mri->getRegClass(li->reg);
- unsigned newVReg = mri->createVirtualRegister(trc);
- vrm->grow();
- LiveInterval *newLI = &lis->getOrCreateInterval(newVReg);
- VNInfo *newVNI = newLI->createValueCopy(vni, lis->getVNInfoAllocator());
-
- // Start by copying all live ranges in the VN to the new interval.
- for (LiveInterval::iterator rItr = li->begin(), rEnd = li->end();
- rItr != rEnd; ++rItr) {
- if (rItr->valno == vni) {
- newLI->addRange(LiveRange(rItr->start, rItr->end, newVNI));
- }
- }
-
- // Erase the old VNI & ranges.
- li->removeValNo(vni);
-
- // Collect all current uses of the register belonging to the given VNI.
- // We'll use this to rename the register after we've dealt with the def.
- std::set<MachineInstr*> uses;
- for (MachineRegisterInfo::use_iterator
- useItr = mri->use_begin(li->reg), useEnd = mri->use_end();
- useItr != useEnd; ++useItr) {
- uses.insert(&*useItr);
- }
-
- // Process the def instruction for this VNI.
- if (newVNI->isPHIDef()) {
- // Insert a copy at the start of the MBB. The range proceeding the
- // copy will be attached to the original LiveInterval.
- MachineBasicBlock *defMBB = lis->getMBBFromIndex(newVNI->def);
- tii->copyRegToReg(*defMBB, defMBB->begin(), newVReg, li->reg, trc, trc);
- MachineInstr *copyMI = defMBB->begin();
- copyMI->addRegisterKilled(li->reg, tri);
- SlotIndex copyIdx = lis->InsertMachineInstrInMaps(copyMI);
- VNInfo *phiDefVNI = li->getNextValue(lis->getMBBStartIdx(defMBB),
- 0, false, lis->getVNInfoAllocator());
- phiDefVNI->setIsPHIDef(true);
- phiDefVNI->addKill(copyIdx.getDefIndex());
- li->addRange(LiveRange(phiDefVNI->def, copyIdx.getDefIndex(), phiDefVNI));
- LiveRange *oldPHIDefRange =
- newLI->getLiveRangeContaining(lis->getMBBStartIdx(defMBB));
-
- // If the old phi def starts in the middle of the range chop it up.
- if (oldPHIDefRange->start < lis->getMBBStartIdx(defMBB)) {
- LiveRange oldPHIDefRange2(copyIdx.getDefIndex(), oldPHIDefRange->end,
- oldPHIDefRange->valno);
- oldPHIDefRange->end = lis->getMBBStartIdx(defMBB);
- newLI->addRange(oldPHIDefRange2);
- } else if (oldPHIDefRange->start == lis->getMBBStartIdx(defMBB)) {
- // Otherwise if it's at the start of the range just trim it.
- oldPHIDefRange->start = copyIdx.getDefIndex();
- } else {
- assert(false && "PHI def range doesn't cover PHI def?");
- }
-
- newVNI->def = copyIdx.getDefIndex();
- newVNI->setCopy(copyMI);
- newVNI->setIsPHIDef(false); // not a PHI def anymore.
- newVNI->setIsDefAccurate(true);
- } else {
- // non-PHI def. Rename the def. If it's two-addr that means renaming the use
- // and inserting a new copy too.
- MachineInstr *defInst = lis->getInstructionFromIndex(newVNI->def);
- // We'll rename this now, so we can remove it from uses.
- uses.erase(defInst);
- unsigned defOpIdx = defInst->findRegisterDefOperandIdx(li->reg);
- bool isTwoAddr = defInst->isRegTiedToUseOperand(defOpIdx),
- twoAddrUseIsUndef = false;
-
- for (unsigned i = 0; i < defInst->getNumOperands(); ++i) {
- MachineOperand &mo = defInst->getOperand(i);
- if (mo.isReg() && (mo.isDef() || isTwoAddr) && (mo.getReg()==li->reg)) {
- mo.setReg(newVReg);
- if (isTwoAddr && mo.isUse() && mo.isUndef())
- twoAddrUseIsUndef = true;
- }
- }
-
- SlotIndex defIdx = lis->getInstructionIndex(defInst);
- newVNI->def = defIdx.getDefIndex();
-
- if (isTwoAddr && !twoAddrUseIsUndef) {
- MachineBasicBlock *defMBB = defInst->getParent();
- tii->copyRegToReg(*defMBB, defInst, newVReg, li->reg, trc, trc);
- MachineInstr *copyMI = prior(MachineBasicBlock::iterator(defInst));
- SlotIndex copyIdx = lis->InsertMachineInstrInMaps(copyMI);
- copyMI->addRegisterKilled(li->reg, tri);
- LiveRange *origUseRange =
- li->getLiveRangeContaining(newVNI->def.getUseIndex());
- VNInfo *origUseVNI = origUseRange->valno;
- origUseRange->end = copyIdx.getDefIndex();
- bool updatedKills = false;
- for (unsigned k = 0; k < origUseVNI->kills.size(); ++k) {
- if (origUseVNI->kills[k] == defIdx.getDefIndex()) {
- origUseVNI->kills[k] = copyIdx.getDefIndex();
- updatedKills = true;
- break;
- }
- }
- assert(updatedKills && "Failed to update VNI kill list.");
- VNInfo *copyVNI = newLI->getNextValue(copyIdx.getDefIndex(), copyMI,
- true, lis->getVNInfoAllocator());
- copyVNI->addKill(defIdx.getDefIndex());
- LiveRange copyRange(copyIdx.getDefIndex(),defIdx.getDefIndex(),copyVNI);
- newLI->addRange(copyRange);
- }
- }
-
- for (std::set<MachineInstr*>::iterator
- usesItr = uses.begin(), usesEnd = uses.end();
- usesItr != usesEnd; ++usesItr) {
- MachineInstr *useInst = *usesItr;
- SlotIndex useIdx = lis->getInstructionIndex(useInst);
- LiveRange *useRange =
- newLI->getLiveRangeContaining(useIdx.getUseIndex());
-
- // If this use doesn't belong to the new interval skip it.
- if (useRange == 0)
- continue;
-
- // This use doesn't belong to the VNI, skip it.
- if (useRange->valno != newVNI)
- continue;
-
- // Check if this instr is two address.
- unsigned useOpIdx = useInst->findRegisterUseOperandIdx(li->reg);
- bool isTwoAddress = useInst->isRegTiedToDefOperand(useOpIdx);
-
- // Rename uses (and defs for two-address instrs).
- for (unsigned i = 0; i < useInst->getNumOperands(); ++i) {
- MachineOperand &mo = useInst->getOperand(i);
- if (mo.isReg() && (mo.isUse() || isTwoAddress) &&
- (mo.getReg() == li->reg)) {
- mo.setReg(newVReg);
- }
- }
-
- // If this is a two address instruction we've got some extra work to do.
- if (isTwoAddress) {
- // We modified the def operand, so we need to copy back to the original
- // reg.
- MachineBasicBlock *useMBB = useInst->getParent();
- MachineBasicBlock::iterator useItr(useInst);
- tii->copyRegToReg(*useMBB, next(useItr), li->reg, newVReg, trc, trc);
- MachineInstr *copyMI = next(useItr);
- copyMI->addRegisterKilled(newVReg, tri);
- SlotIndex copyIdx = lis->InsertMachineInstrInMaps(copyMI);
-
- // Change the old two-address defined range & vni to start at
- // (and be defined by) the copy.
- LiveRange *origDefRange =
- li->getLiveRangeContaining(useIdx.getDefIndex());
- origDefRange->start = copyIdx.getDefIndex();
- origDefRange->valno->def = copyIdx.getDefIndex();
- origDefRange->valno->setCopy(copyMI);
-
- // Insert a new range & vni for the two-address-to-copy value. This
- // will be attached to the new live interval.
- VNInfo *copyVNI =
- newLI->getNextValue(useIdx.getDefIndex(), 0, true,
- lis->getVNInfoAllocator());
- copyVNI->addKill(copyIdx.getDefIndex());
- LiveRange copyRange(useIdx.getDefIndex(),copyIdx.getDefIndex(),copyVNI);
- newLI->addRange(copyRange);
- }
- }
-
- // Iterate over any PHI kills - we'll need to insert new copies for them.
- for (VNInfo::KillSet::iterator
- killItr = newVNI->kills.begin(), killEnd = newVNI->kills.end();
- killItr != killEnd; ++killItr) {
- SlotIndex killIdx(*killItr);
- if (killItr->isPHI()) {
- MachineBasicBlock *killMBB = lis->getMBBFromIndex(killIdx);
- LiveRange *oldKillRange =
- newLI->getLiveRangeContaining(killIdx);
-
- assert(oldKillRange != 0 && "No kill range?");
-
- tii->copyRegToReg(*killMBB, killMBB->getFirstTerminator(),
- li->reg, newVReg, trc, trc);
- MachineInstr *copyMI = prior(killMBB->getFirstTerminator());
- copyMI->addRegisterKilled(newVReg, tri);
- SlotIndex copyIdx = lis->InsertMachineInstrInMaps(copyMI);
-
- // Save the current end. We may need it to add a new range if the
- // current range runs of the end of the MBB.
- SlotIndex newKillRangeEnd = oldKillRange->end;
- oldKillRange->end = copyIdx.getDefIndex();
-
- if (newKillRangeEnd != lis->getMBBEndIdx(killMBB)) {
- assert(newKillRangeEnd > lis->getMBBEndIdx(killMBB) &&
- "PHI kill range doesn't reach kill-block end. Not sane.");
- newLI->addRange(LiveRange(lis->getMBBEndIdx(killMBB),
- newKillRangeEnd, newVNI));
- }
-
- *killItr = oldKillRange->end;
- VNInfo *newKillVNI = li->getNextValue(copyIdx.getDefIndex(),
- copyMI, true,
- lis->getVNInfoAllocator());
- newKillVNI->addKill(lis->getMBBTerminatorGap(killMBB));
- newKillVNI->setHasPHIKill(true);
- li->addRange(LiveRange(copyIdx.getDefIndex(),
- lis->getMBBEndIdx(killMBB),
- newKillVNI));
- }
-
- }
-
- newVNI->setHasPHIKill(false);
-
- return newLI;
- }
-
-};
-
-}
+void Spiller::anchor() { }
-llvm::Spiller* llvm::createSpiller(MachineFunction *mf, LiveIntervals *lis,
- const MachineLoopInfo *loopInfo,
- VirtRegMap *vrm) {
+llvm::Spiller* llvm::createSpiller(MachineFunctionPass &pass,
+ MachineFunction &mf,
+ VirtRegMap &vrm) {
switch (spillerOpt) {
- case trivial: return new TrivialSpiller(mf, lis, vrm); break;
- case standard: return new StandardSpiller(lis, loopInfo, vrm); break;
- case splitting: return new SplittingSpiller(mf, lis, loopInfo, vrm); break;
- default: llvm_unreachable("Unreachable!"); break;
+ case trivial: return new TrivialSpiller(pass, mf, vrm);
+ case inline_: return createInlineSpiller(pass, mf, vrm);
}
+ llvm_unreachable("Invalid spiller optimization");
}