Delete SplittingSpiller. It was not being used by anyone, and it is being

superceded by SplitKit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118754 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen 2010-11-11 00:52:44 +00:00
parent 8a66a202f6
commit a05f60b241

View File

@ -29,7 +29,7 @@
using namespace llvm;
namespace {
enum SpillerName { trivial, standard, splitting, inline_ };
enum SpillerName { trivial, standard, inline_ };
}
static cl::opt<SpillerName>
@ -38,7 +38,6 @@ spillerOpt("spiller",
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));
@ -232,289 +231,6 @@ public:
} // end anonymous namespace
namespace {
/// 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(MachineFunctionPass &pass, MachineFunction &mf,
VirtRegMap &vrm)
: StandardSpiller(pass, mf, vrm) {
mri = &mf.getRegInfo();
tii = mf.getTarget().getInstrInfo();
tri = mf.getTarget().getRegisterInfo();
}
void spill(LiveInterval *li,
SmallVectorImpl<LiveInterval*> &newIntervals,
const SmallVectorImpl<LiveInterval*> &spillIs) {
if (worthTryingToSplit(li))
tryVNISplit(li);
else
StandardSpiller::spill(li, newIntervals, spillIs);
}
private:
MachineRegisterInfo *mri;
const TargetInstrInfo *tii;
const TargetRegisterInfo *tri;
DenseSet<LiveInterval*> alreadySplit;
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) {
DEBUG(dbgs() << "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.
if (vni->isUnused())
continue;
DEBUG(dbgs() << " Extracted Val #" << vni->id << " as ");
LiveInterval *splitInterval = extractVNI(li, vni);
if (splitInterval != 0) {
DEBUG(dbgs() << *splitInterval << "\n");
added.push_back(splitInterval);
alreadySplit.insert(splitInterval);
} else {
DEBUG(dbgs() << "0\n");
}
}
DEBUG(dbgs() << "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);
}
return added;
}
/// Extract the given value number from the interval.
LiveInterval* extractVNI(LiveInterval *li, VNInfo *vni) const {
assert((lis->getInstructionFromIndex(vni->def) != 0 || vni->isPHIDef()) &&
"Def index not sane?");
// Create a new vreg and live interval, copy VNI 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);
MachineInstr *copyMI = BuildMI(*defMBB, defMBB->begin(), DebugLoc(),
tii->get(TargetOpcode::COPY), newVReg)
.addReg(li->reg, RegState::Kill);
SlotIndex copyIdx = lis->InsertMachineInstrInMaps(copyMI);
SlotIndex phiDefIdx = lis->getMBBStartIdx(defMBB);
assert(lis->getInstructionFromIndex(phiDefIdx) == 0 &&
"PHI def index points at actual instruction.");
VNInfo *phiDefVNI = li->getNextValue(phiDefIdx,
0, lis->getVNInfoAllocator());
phiDefVNI->setIsPHIDef(true);
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.
} 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();
MachineInstr *copyMI = BuildMI(*defMBB, defInst, DebugLoc(),
tii->get(TargetOpcode::COPY), newVReg)
.addReg(li->reg, RegState::Kill);
SlotIndex copyIdx = lis->InsertMachineInstrInMaps(copyMI);
LiveRange *origUseRange =
li->getLiveRangeContaining(newVNI->def.getUseIndex());
origUseRange->end = copyIdx.getDefIndex();
VNInfo *copyVNI = newLI->getNextValue(copyIdx.getDefIndex(), copyMI,
lis->getVNInfoAllocator());
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);
MachineInstr *copyMI = BuildMI(*useMBB, llvm::next(useItr), DebugLoc(),
tii->get(TargetOpcode::COPY), newVReg)
.addReg(li->reg, RegState::Kill);
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,
lis->getVNInfoAllocator());
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 (LiveInterval::iterator LRI = newLI->begin(), LRE = newLI->end();
LRI != LRE; ++LRI) {
if (LRI->valno != newVNI)
continue;
SlotIndex killIdx = LRI->end;
MachineBasicBlock *killMBB = lis->getMBBFromIndex(killIdx);
MachineInstr *copyMI = BuildMI(*killMBB, killMBB->getFirstTerminator(),
DebugLoc(), tii->get(TargetOpcode::COPY),
li->reg)
.addReg(newVReg, RegState::Kill);
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 = LRI->end;
LRI->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));
}
VNInfo *newKillVNI = li->getNextValue(copyIdx.getDefIndex(),
copyMI, lis->getVNInfoAllocator());
newKillVNI->setHasPHIKill(true);
li->addRange(LiveRange(copyIdx.getDefIndex(),
lis->getMBBEndIdx(killMBB),
newKillVNI));
}
newVNI->setHasPHIKill(false);
return newLI;
}
};
} // end anonymous namespace
namespace llvm {
Spiller *createInlineSpiller(MachineFunctionPass &pass,
MachineFunction &mf,
@ -528,7 +244,6 @@ llvm::Spiller* llvm::createSpiller(MachineFunctionPass &pass,
default: assert(0 && "unknown spiller");
case trivial: return new TrivialSpiller(pass, mf, vrm);
case standard: return new StandardSpiller(pass, mf, vrm);
case splitting: return new SplittingSpiller(pass, mf, vrm);
case inline_: return createInlineSpiller(pass, mf, vrm);
}
}