Recover compile time regression.

llvm-svn: 44386
This commit is contained in:
Evan Cheng 2007-11-28 01:28:46 +00:00
parent 2b9b50b985
commit 05d30e7236
4 changed files with 76 additions and 89 deletions

View File

@ -292,7 +292,7 @@ namespace llvm {
VirtRegMap &vrm, SSARegMap *RegMap, const TargetRegisterClass* rc,
SmallVector<int, 4> &ReMatIds,
unsigned &NewVReg, bool &HasDef, bool &HasUse, const LoopInfo *loopInfo,
std::vector<unsigned> &NewVRegs,
std::map<unsigned,unsigned> &NewVRegs,
std::vector<LiveInterval*> &NewLIs);
void rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit,
LiveInterval::Ranges::const_iterator &I,
@ -301,8 +301,8 @@ namespace llvm {
VirtRegMap &vrm, SSARegMap *RegMap, const TargetRegisterClass* rc,
SmallVector<int, 4> &ReMatIds, const LoopInfo *loopInfo,
BitVector &SpillMBBs,
std::vector<std::pair<int, unsigned> > &SpillIdxes,
std::vector<unsigned> &NewVRegs,
std::map<unsigned, std::pair<int, unsigned> > &SpillIdxes,
std::map<unsigned,unsigned> &NewVRegs,
std::vector<LiveInterval*> &NewLIs);
static LiveInterval createInterval(unsigned Reg);

View File

@ -707,7 +707,8 @@ rewriteInstructionForSpills(const LiveInterval &li, bool TrySplit,
const TargetRegisterClass* rc,
SmallVector<int, 4> &ReMatIds,
unsigned &NewVReg, bool &HasDef, bool &HasUse,
const LoopInfo *loopInfo, std::vector<unsigned> &NewVRegs,
const LoopInfo *loopInfo,
std::map<unsigned,unsigned> &NewVRegs,
std::vector<LiveInterval*> &NewLIs) {
RestartInstruction:
for (unsigned i = 0; i != MI->getNumOperands(); ++i) {
@ -731,6 +732,7 @@ rewriteInstructionForSpills(const LiveInterval &li, bool TrySplit,
// all of its uses are rematerialized, simply delete it.
if (MI == ReMatOrigDefMI && CanDelete) {
RemoveMachineInstrFromMaps(MI);
vrm.RemoveMachineInstrFromMaps(MI);
MI->eraseFromParent();
break;
}
@ -823,7 +825,7 @@ rewriteInstructionForSpills(const LiveInterval &li, bool TrySplit,
LiveInterval &nI = getOrCreateInterval(NewVReg);
if (CreatedNewVReg) {
NewLIs.push_back(&nI);
NewVRegs[MI->getParent()->getNumber()] = NewVReg;
NewVRegs.insert(std::make_pair(MI->getParent()->getNumber(), NewVReg));
if (TrySplit)
vrm.setIsSplitFromReg(NewVReg, li.reg);
}
@ -893,8 +895,8 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit,
SmallVector<int, 4> &ReMatIds,
const LoopInfo *loopInfo,
BitVector &SpillMBBs,
std::vector<std::pair<int, unsigned> > &SpillIdxes,
std::vector<unsigned> &NewVRegs,
std::map<unsigned, std::pair<int, unsigned> > &SpillIdxes,
std::map<unsigned,unsigned> &NewVRegs,
std::vector<LiveInterval*> &NewLIs) {
unsigned NewVReg = 0;
unsigned index = getBaseIndex(I->start);
@ -908,7 +910,13 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit,
MachineInstr *MI = getInstructionFromIndex(index);
MachineBasicBlock *MBB = MI->getParent();
NewVReg = !TrySplitMI ? 0 : NewVRegs[MBB->getNumber()];
NewVReg = 0;
if (TrySplitMI) {
std::map<unsigned,unsigned>::const_iterator NVI =
NewVRegs.find(MBB->getNumber());
if (NVI != NewVRegs.end())
NewVReg = NVI->second;
}
bool IsNew = NewVReg == 0;
bool HasDef = false;
bool HasUse = false;
@ -936,9 +944,11 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit,
: anyKillInMBBAfterIdx(li, MBB, getDefIndex(index), I->valno);
if (!HasKill) {
unsigned MBBId = MBB->getNumber();
if ((int)index > SpillIdxes[MBBId].first)
// High bit specify whether this spill ought to be folded if
// possible.
// High bit specify whether this spill ought to be folded if
// possible.
std::map<unsigned, std::pair<int,unsigned> >::iterator SII =
SpillIdxes.find(MBBId);
if (SII == SpillIdxes.end() || (int)index > SII->second.first)
SpillIdxes[MBBId] = std::make_pair(index, NewVReg | (1 << 31));
SpillMBBs.set(MBBId);
}
@ -955,8 +965,11 @@ rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit,
} else if (HasUse) {
// Use(s) following the last def, it's not safe to fold the spill.
unsigned MBBId = MBB->getNumber();
if ((SpillIdxes[MBBId].second & ((1<<31)-1)) == NewVReg &&
(int)getUseIndex(index) > SpillIdxes[MBBId].first)
std::map<unsigned, std::pair<int,unsigned> >::iterator SII =
SpillIdxes.find(MBBId);
if (SII != SpillIdxes.end() &&
(SII->second.second & ((1<<31)-1)) == NewVReg &&
(int)getUseIndex(index) > SII->second.first)
SpillIdxes[MBBId].second &= (1<<31)-1;
}
@ -985,9 +998,8 @@ addIntervalsForSpills(const LiveInterval &li,
// Each bit specify whether it a spill is required in the MBB.
BitVector SpillMBBs(mf_->getNumBlockIDs());
std::vector<std::pair<int, unsigned> > SpillIdxes(mf_->getNumBlockIDs(),
std::make_pair(-1,0));
std::vector<unsigned> NewVRegs(mf_->getNumBlockIDs(), 0);
std::map<unsigned, std::pair<int, unsigned> > SpillIdxes;
std::map<unsigned,unsigned> NewVRegs;
std::vector<LiveInterval*> NewLIs;
SSARegMap *RegMap = mf_->getSSARegMap();
const TargetRegisterClass* rc = RegMap->getRegClass(li.reg);
@ -1015,7 +1027,6 @@ addIntervalsForSpills(const LiveInterval &li,
bool isLoadSS = DefIsReMat && tii_->isLoadFromStackSlot(ReMatDefMI, LdSlot);
bool isLoad = isLoadSS ||
(DefIsReMat && (ReMatDefMI->getInstrDescriptor()->Flags & M_LOAD_FLAG));
vrm.removeAllSpillPtsForReg(li.reg);
bool IsFirstRange = true;
for (LiveInterval::Ranges::const_iterator
I = li.ranges.begin(), E = li.ranges.end(); I != E; ++I) {
@ -1087,7 +1098,6 @@ addIntervalsForSpills(const LiveInterval &li,
if (NeedStackSlot && vrm.getPreSplitReg(li.reg) == 0)
Slot = vrm.assignVirt2StackSlot(li.reg);
// Create new intervals and rewrite defs and uses.
for (LiveInterval::Ranges::const_iterator
I = li.ranges.begin(), E = li.ranges.end(); I != E; ++I) {

View File

@ -74,7 +74,6 @@ void VirtRegMap::grow() {
Virt2StackSlotMap.grow(LastVirtReg);
Virt2ReMatIdMap.grow(LastVirtReg);
Virt2SplitMap.grow(LastVirtReg);
Virt2SpillPtsMap.grow(LastVirtReg);
ReMatMap.grow(LastVirtReg);
}
@ -837,7 +836,7 @@ bool LocalSpiller::PrepForUnfoldOpti(MachineBasicBlock &MBB,
VRM.assignVirt2Phys(UnfoldVR, UnfoldPR);
VRM.virtFolded(VirtReg, FoldedMI, VirtRegMap::isRef);
MII = MBB.insert(MII, FoldedMI);
VRM.RemoveFromFoldedVirtMap(&MI);
VRM.RemoveMachineInstrFromMaps(&MI);
MBB.erase(&MI);
return true;
}
@ -886,7 +885,7 @@ void LocalSpiller::SpillRegToStackSlot(MachineBasicBlock &MBB,
if (CheckDef)
--PrevMII;
MBB.erase(LastStore);
VRM.RemoveFromFoldedVirtMap(LastStore);
VRM.RemoveMachineInstrFromMaps(LastStore);
if (CheckDef) {
// Look at defs of killed registers on the store. Mark the defs
// as dead since the store has been deleted and they aren't
@ -899,7 +898,7 @@ void LocalSpiller::SpillRegToStackSlot(MachineBasicBlock &MBB,
// FIXME: This assumes a remat def does not have side
// effects.
MBB.erase(DeadDef);
VRM.RemoveFromFoldedVirtMap(DeadDef);
VRM.RemoveMachineInstrFromMaps(DeadDef);
++NumDRM;
}
}
@ -965,15 +964,19 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
const TargetInstrDescriptor *TID = MI.getInstrDescriptor();
// Insert spills here if asked to.
std::vector<unsigned> SpillRegs = VRM.getSpillPtSpills(&MI);
for (unsigned i = 0, e = SpillRegs.size(); i != e; ++i) {
unsigned VirtReg = SpillRegs[i];
const TargetRegisterClass *RC = RegMap->getRegClass(VirtReg);
unsigned Phys = VRM.getPhys(VirtReg);
int StackSlot = VRM.getStackSlot(VirtReg);
MachineInstr *&LastStore = MaybeDeadStores[StackSlot];
SpillRegToStackSlot(MBB, MII, i, Phys, StackSlot, RC,
LastStore, Spills, ReMatDefs, RegKills, KillOps, VRM);
if (VRM.isSpillPt(&MI)) {
std::vector<unsigned> &SpillRegs = VRM.getSpillPtSpills(&MI);
for (unsigned i = 0, e = SpillRegs.size(); i != e; ++i) {
unsigned VirtReg = SpillRegs[i];
if (!VRM.getPreSplitReg(VirtReg))
continue; // Split interval spilled again.
const TargetRegisterClass *RC = RegMap->getRegClass(VirtReg);
unsigned Phys = VRM.getPhys(VirtReg);
int StackSlot = VRM.getStackSlot(VirtReg);
MachineInstr *&LastStore = MaybeDeadStores[StackSlot];
SpillRegToStackSlot(MBB, MII, i, Phys, StackSlot, RC,
LastStore, Spills, ReMatDefs, RegKills, KillOps, VRM);
}
}
/// ReusedOperands - Keep track of operand reuse in case we need to undo
@ -1142,7 +1145,7 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
if (DeadStore) {
DOUT << "Removed dead store:\t" << *DeadStore;
InvalidateKills(*DeadStore, RegKills, KillOps);
VRM.RemoveFromFoldedVirtMap(DeadStore);
VRM.RemoveMachineInstrFromMaps(DeadStore);
MBB.erase(DeadStore);
MaybeDeadStores[ReuseSlot] = NULL;
++NumDSE;
@ -1295,7 +1298,7 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
} else
DOUT << "Removing now-noop copy: " << MI;
VRM.RemoveFromFoldedVirtMap(&MI);
VRM.RemoveMachineInstrFromMaps(&MI);
MBB.erase(&MI);
Erased = true;
goto ProcessNextInst;
@ -1306,7 +1309,7 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
if (PhysReg &&
MRI->unfoldMemoryOperand(MF, &MI, PhysReg, false, false, NewMIs)) {
MBB.insert(MII, NewMIs[0]);
VRM.RemoveFromFoldedVirtMap(&MI);
VRM.RemoveMachineInstrFromMaps(&MI);
MBB.erase(&MI);
Erased = true;
--NextMII; // backtrack to the unfolded instruction.
@ -1331,7 +1334,7 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
MBB.insert(MII, NewMIs[0]);
NewStore = NewMIs[1];
MBB.insert(MII, NewStore);
VRM.RemoveFromFoldedVirtMap(&MI);
VRM.RemoveMachineInstrFromMaps(&MI);
MBB.erase(&MI);
Erased = true;
--NextMII;
@ -1345,7 +1348,7 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
// If we get here, the store is dead, nuke it now.
DOUT << "Removed dead store:\t" << *DeadStore;
InvalidateKills(*DeadStore, RegKills, KillOps);
VRM.RemoveFromFoldedVirtMap(DeadStore);
VRM.RemoveMachineInstrFromMaps(DeadStore);
MBB.erase(DeadStore);
if (!NewStore)
++NumDSE;
@ -1405,7 +1408,7 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
DOUT << "Removing now-noop copy: " << MI;
MBB.erase(&MI);
Erased = true;
VRM.RemoveFromFoldedVirtMap(&MI);
VRM.RemoveMachineInstrFromMaps(&MI);
Spills.disallowClobberPhysReg(VirtReg);
goto ProcessNextInst;
}
@ -1480,7 +1483,7 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
DOUT << "Removing now-noop copy: " << MI;
MBB.erase(&MI);
Erased = true;
VRM.RemoveFromFoldedVirtMap(&MI);
VRM.RemoveMachineInstrFromMaps(&MI);
UpdateKills(*LastStore, RegKills, KillOps);
goto ProcessNextInst;
}
@ -1495,7 +1498,6 @@ void LocalSpiller::RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM) {
}
}
llvm::Spiller* llvm::createSpiller() {
switch (SpillerOpt) {
default: assert(0 && "Unreachable!");

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@ -80,12 +80,7 @@ namespace llvm {
/// SpillPt2VirtMap - This records the virtual registers which should
/// be spilled right after the MachineInstr due to live interval
/// splitting.
DenseMap<MachineInstr*, std::vector<unsigned> > SpillPt2VirtMap;
/// Virt2SplitMap - This records the MachineInstrs where a virtual
/// register should be spilled due to live interval splitting.
IndexedMap<std::vector<MachineInstr*>, VirtReg2IndexFunctor>
Virt2SpillPtsMap;
std::map<MachineInstr*, std::vector<unsigned> > SpillPt2VirtMap;
/// ReMatId - Instead of assigning a stack slot to a to be rematerialized
/// virtual register, an unique id is being assigned. This keeps track of
@ -209,6 +204,11 @@ namespace llvm {
ReMatMap[virtReg] = def;
}
/// @brief returns true if the specified MachineInstr is a spill point.
bool isSpillPt(MachineInstr *Pt) const {
return SpillPt2VirtMap.find(Pt) != SpillPt2VirtMap.end();
}
/// @brief returns the virtual registers that should be spilled due to
/// splitting right after the specified MachineInstr.
std::vector<unsigned> &getSpillPtSpills(MachineInstr *Pt) {
@ -217,52 +217,26 @@ namespace llvm {
/// @brief records the specified MachineInstr as a spill point for virtReg.
void addSpillPoint(unsigned virtReg, MachineInstr *Pt) {
SpillPt2VirtMap[Pt].push_back(virtReg);
Virt2SpillPtsMap[virtReg].push_back(Pt);
}
/// @brief remove the virtReg from the list of registers that should be
/// spilled (due to splitting) right after the specified MachineInstr.
void removeRegFromSpillPt(MachineInstr *Pt, unsigned virtReg) {
std::vector<unsigned> &Regs = SpillPt2VirtMap[Pt];
if (Regs.back() == virtReg) // Most common case.
Regs.pop_back();
for (unsigned i = 0, e = Regs.size(); i != e; ++i)
if (Regs[i] == virtReg) {
Regs.erase(Regs.begin()+i-1);
break;
}
}
/// @brief specify virtReg is no longer being spilled due to splitting.
void removeAllSpillPtsForReg(unsigned virtReg) {
std::vector<MachineInstr*> &SpillPts = Virt2SpillPtsMap[virtReg];
for (unsigned i = 0, e = SpillPts.size(); i != e; ++i)
removeRegFromSpillPt(SpillPts[i], virtReg);
Virt2SpillPtsMap[virtReg].clear();
}
/// @brief remove the specified MachineInstr as a spill point for the
/// specified register.
void removeRegSpillPt(unsigned virtReg, MachineInstr *Pt) {
std::vector<MachineInstr*> &SpillPts = Virt2SpillPtsMap[virtReg];
if (SpillPts.back() == Pt) // Most common case.
SpillPts.pop_back();
for (unsigned i = 0, e = SpillPts.size(); i != e; ++i)
if (SpillPts[i] == Pt) {
SpillPts.erase(SpillPts.begin()+i-1);
break;
}
if (SpillPt2VirtMap.find(Pt) != SpillPt2VirtMap.end())
SpillPt2VirtMap[Pt].push_back(virtReg);
else {
std::vector<unsigned> Virts;
Virts.push_back(virtReg);
SpillPt2VirtMap.insert(std::make_pair(Pt, Virts));
}
}
void transferSpillPts(MachineInstr *Old, MachineInstr *New) {
std::vector<unsigned> &OldRegs = SpillPt2VirtMap[Old];
while (!OldRegs.empty()) {
unsigned virtReg = OldRegs.back();
OldRegs.pop_back();
removeRegSpillPt(virtReg, Old);
std::map<MachineInstr*,std::vector<unsigned> >::iterator I =
SpillPt2VirtMap.find(Old);
if (I == SpillPt2VirtMap.end())
return;
while (!I->second.empty()) {
unsigned virtReg = I->second.back();
I->second.pop_back();
addSpillPoint(virtReg, New);
}
SpillPt2VirtMap.erase(I);
}
/// @brief Updates information about the specified virtual register's value
@ -282,10 +256,11 @@ namespace llvm {
return MI2VirtMap.equal_range(MI);
}
/// RemoveFromFoldedVirtMap - If the specified machine instruction is in
/// the folded instruction map, remove its entry from the map.
void RemoveFromFoldedVirtMap(MachineInstr *MI) {
/// RemoveMachineInstrFromMaps - MI is being erased, remove it from the
/// the folded instruction map and spill point map.
void RemoveMachineInstrFromMaps(MachineInstr *MI) {
MI2VirtMap.erase(MI);
SpillPt2VirtMap.erase(MI);
}
void print(std::ostream &OS) const;