avoid calling the virtual isMoveInstr method endlessly by caching its results.

llvm-svn: 29994
This commit is contained in:
Chris Lattner 2006-08-31 05:54:43 +00:00
parent b096190f29
commit aa36808fd3
4 changed files with 107 additions and 94 deletions

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@ -78,10 +78,12 @@ namespace llvm {
float weight; // weight of this interval
Ranges ranges; // the ranges in which this register is live
private:
/// InstDefiningValue - This tracks the def index of the instruction that
/// defines a particular value number in the interval. This may be ~0,
/// which is treated as unknown, or ~1, which is a deleted value number.
SmallVector<unsigned, 4> InstDefiningValue;
/// ValueNumberInfo - If this value number is not defined by a copy, this
/// holds ~0,x. If the value number is not in use, it contains ~1,x to
/// indicate that the value # is not used. If the val# is defined by a
/// copy, the first entry is the instruction # of the copy, and the second
/// is the register number copied from.
SmallVector<std::pair<unsigned,unsigned>, 4> ValueNumberInfo;
public:
LiveInterval(unsigned Reg, float Weight)
@ -113,31 +115,44 @@ namespace llvm {
std::swap(reg, other.reg);
std::swap(weight, other.weight);
std::swap(ranges, other.ranges);
std::swap(InstDefiningValue, other.InstDefiningValue);
std::swap(ValueNumberInfo, other.ValueNumberInfo);
}
bool containsOneValue() const { return InstDefiningValue.size() == 1; }
bool containsOneValue() const { return ValueNumberInfo.size() == 1; }
unsigned getNumValNums() const { return InstDefiningValue.size(); }
unsigned getNumValNums() const { return ValueNumberInfo.size(); }
/// getNextValue - Create a new value number and return it. MIIdx specifies
/// the instruction that defines the value number.
unsigned getNextValue(unsigned MIIdx) {
InstDefiningValue.push_back(MIIdx);
return InstDefiningValue.size()-1;
unsigned getNextValue(unsigned MIIdx, unsigned SrcReg) {
ValueNumberInfo.push_back(std::make_pair(MIIdx, SrcReg));
return ValueNumberInfo.size()-1;
}
/// getInstForValNum - Return the machine instruction index that defines the
/// specified value number.
unsigned getInstForValNum(unsigned ValNo) const {
assert(ValNo < InstDefiningValue.size());
return InstDefiningValue[ValNo];
assert(ValNo < ValueNumberInfo.size());
return ValueNumberInfo[ValNo].first;
}
/// setInstDefiningValNum - Change the instruction defining the specified
/// value number to the specified instruction.
void setInstDefiningValNum(unsigned ValNo, unsigned MIIdx) {
InstDefiningValue[ValNo] = MIIdx;
unsigned getSrcRegForValNum(unsigned ValNo) const {
assert(ValNo < ValueNumberInfo.size());
if (ValueNumberInfo[ValNo].first < ~2U)
return ValueNumberInfo[ValNo].second;
return 0;
}
std::pair<unsigned, unsigned> getValNumInfo(unsigned ValNo) const {
assert(ValNo < ValueNumberInfo.size());
return ValueNumberInfo[ValNo];
}
/// setValueNumberInfo - Change the value number info for the specified
/// value number.
void setValueNumberInfo(unsigned ValNo,
const std::pair<unsigned, unsigned> &I){
ValueNumberInfo[ValNo] = I;
}
/// MergeValueNumberInto - This method is called when two value nubmers
@ -216,7 +231,7 @@ namespace llvm {
/// the intervals are not joinable, this aborts.
void join(LiveInterval &Other, int *ValNoAssignments,
int *RHSValNoAssignments,
SmallVector<unsigned, 16> &NewInstDefiningValue);
SmallVector<std::pair<unsigned,unsigned>,16> &NewValueNumberInfo);
/// removeRange - Remove the specified range from this interval. Note that

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@ -198,8 +198,8 @@ namespace llvm {
/// def.
void handlePhysicalRegisterDef(MachineBasicBlock* mbb,
MachineBasicBlock::iterator mi,
LiveInterval& interval,
bool isLiveIn = false);
LiveInterval &interval,
unsigned SrcReg);
/// Return true if the two specified registers belong to different
/// register classes. The registers may be either phys or virt regs.

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@ -280,7 +280,8 @@ LiveInterval::FindLiveRangeContaining(unsigned Idx) {
/// the intervals are not joinable, this aborts.
void LiveInterval::join(LiveInterval &Other, int *LHSValNoAssignments,
int *RHSValNoAssignments,
SmallVector<unsigned, 16> &NewInstDefiningValue) {
SmallVector<std::pair<unsigned,
unsigned>, 16> &NewValueNumberInfo) {
// Try to do the least amount of work possible. In particular, if there are
// more liverange chunks in the other set than there are in the 'this' set,
@ -300,7 +301,7 @@ void LiveInterval::join(LiveInterval &Other, int *LHSValNoAssignments,
// we want to avoid the interval scan if not.
bool MustMapCurValNos = false;
for (unsigned i = 0, e = getNumValNums(); i != e; ++i) {
if (InstDefiningValue[i] == ~2U) continue; // tombstone value #
if (ValueNumberInfo[i].first == ~2U) continue; // tombstone value #
if (i != (unsigned)LHSValNoAssignments[i]) {
MustMapCurValNos = true;
break;
@ -345,9 +346,8 @@ void LiveInterval::join(LiveInterval &Other, int *LHSValNoAssignments,
InsertPos = addRangeFrom(*I, InsertPos);
}
InstDefiningValue.clear();
InstDefiningValue.append(NewInstDefiningValue.begin(),
NewInstDefiningValue.end());
ValueNumberInfo.clear();
ValueNumberInfo.append(NewValueNumberInfo.begin(), NewValueNumberInfo.end());
weight += Other.weight;
}
@ -360,7 +360,7 @@ void LiveInterval::MergeInClobberRanges(const LiveInterval &Clobbers) {
// Find a value # to use for the clobber ranges. If there is already a value#
// for unknown values, use it.
// FIXME: Use a single sentinal number for these!
unsigned ClobberValNo = getNextValue(~0U);
unsigned ClobberValNo = getNextValue(~0U, 0);
iterator IP = begin();
for (const_iterator I = Clobbers.begin(), E = Clobbers.end(); I != E; ++I) {
@ -399,7 +399,7 @@ void LiveInterval::MergeValueNumberInto(unsigned V1, unsigned V2) {
// Make sure V2 is smaller than V1.
if (V1 < V2) {
setInstDefiningValNum(V1, getInstForValNum(V2));
setValueNumberInfo(V1, getValNumInfo(V2));
std::swap(V1, V2);
}
@ -443,10 +443,10 @@ void LiveInterval::MergeValueNumberInto(unsigned V1, unsigned V2) {
// ~1U so it can be nuked later.
if (V1 == getNumValNums()-1) {
do {
InstDefiningValue.pop_back();
} while (InstDefiningValue.back() == ~1U);
ValueNumberInfo.pop_back();
} while (ValueNumberInfo.back().first == ~1U);
} else {
InstDefiningValue[V1] = ~1U;
ValueNumberInfo[V1].first = ~1U;
}
}
@ -482,10 +482,10 @@ void LiveInterval::print(std::ostream &OS, const MRegisterInfo *MRI) const {
for (unsigned i = 0; i != getNumValNums(); ++i) {
if (i) OS << " ";
OS << i << "@";
if (InstDefiningValue[i] == ~0U) {
if (ValueNumberInfo[i].first == ~0U) {
OS << "?";
} else {
OS << InstDefiningValue[i];
OS << ValueNumberInfo[i].first;
}
}
}

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@ -138,10 +138,10 @@ bool LiveIntervals::runOnMachineFunction(MachineFunction &fn) {
for (MachineFunction::livein_iterator I = fn.livein_begin(),
E = fn.livein_end(); I != E; ++I) {
handlePhysicalRegisterDef(Entry, Entry->begin(),
getOrCreateInterval(I->first), true);
getOrCreateInterval(I->first), 0);
for (const unsigned* AS = mri_->getAliasSet(I->first); *AS; ++AS)
handlePhysicalRegisterDef(Entry, Entry->begin(),
getOrCreateInterval(*AS), true);
getOrCreateInterval(*AS), 0);
}
}
@ -321,7 +321,7 @@ addIntervalsForSpills(const LiveInterval &li, VirtRegMap &vrm, int slot) {
// the spill weight is now infinity as it
// cannot be spilled again
nI.weight = float(HUGE_VAL);
LiveRange LR(start, end, nI.getNextValue(~0U));
LiveRange LR(start, end, nI.getNextValue(~0U, 0));
DEBUG(std::cerr << " +" << LR);
nI.addRange(LR);
added.push_back(&nI);
@ -366,7 +366,13 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb,
// Get the Idx of the defining instructions.
unsigned defIndex = getDefIndex(getInstructionIndex(mi));
unsigned ValNum = interval.getNextValue(defIndex);
unsigned ValNum;
unsigned SrcReg, DstReg;
if (!tii_->isMoveInstr(*mi, SrcReg, DstReg))
ValNum = interval.getNextValue(~0U, 0);
else
ValNum = interval.getNextValue(defIndex, SrcReg);
assert(ValNum == 0 && "First value in interval is not 0?");
ValNum = 0; // Clue in the optimizer.
@ -455,12 +461,13 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb,
// that at this point, there should be exactly one value number in it.
assert(interval.containsOneValue() && "Unexpected 2-addr liveint!");
// The new value number is defined by the instruction we claimed defined
// value #0.
unsigned ValNo = interval.getNextValue(DefIndex);
// The new value number (#1) is defined by the instruction we claimed
// defined value #0.
unsigned ValNo = interval.getNextValue(0, 0);
interval.setValueNumberInfo(1, interval.getValNumInfo(0));
// Value#1 is now defined by the 2-addr instruction.
interval.setInstDefiningValNum(0, RedefIndex);
// Value#0 is now defined by the 2-addr instruction.
interval.setValueNumberInfo(0, std::make_pair(~0U, 0U));
// Add the new live interval which replaces the range for the input copy.
LiveRange LR(DefIndex, RedefIndex, ValNo);
@ -493,7 +500,7 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb,
// 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(~0U));
LiveRange LR(Start, End, interval.getNextValue(~0U, 0));
DEBUG(std::cerr << " replace range with " << LR);
interval.addRange(LR);
DEBUG(std::cerr << "RESULT: "; interval.print(std::cerr, mri_));
@ -503,9 +510,16 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb,
// live until the end of the block. We've already taken care of the
// rest of the live range.
unsigned defIndex = getDefIndex(getInstructionIndex(mi));
unsigned ValNum;
unsigned SrcReg, DstReg;
if (!tii_->isMoveInstr(*mi, SrcReg, DstReg))
ValNum = interval.getNextValue(~0U, 0);
else
ValNum = interval.getNextValue(defIndex, SrcReg);
LiveRange LR(defIndex,
getInstructionIndex(&mbb->back()) + InstrSlots::NUM,
interval.getNextValue(defIndex));
getInstructionIndex(&mbb->back()) + InstrSlots::NUM, ValNum);
interval.addRange(LR);
DEBUG(std::cerr << " +" << LR);
}
@ -516,8 +530,8 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock *mbb,
void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock *MBB,
MachineBasicBlock::iterator mi,
LiveInterval& interval,
bool isLiveIn) {
LiveInterval &interval,
unsigned SrcReg) {
// A physical register cannot be live across basic block, so its
// lifetime must end somewhere in its defining basic block.
DEBUG(std::cerr << "\t\tregister: "; printRegName(interval.reg));
@ -551,13 +565,14 @@ void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock *MBB,
// 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(isLiveIn && "physreg was not killed in defining block!");
assert(!SrcReg && "physreg was not killed in defining block!");
end = getDefIndex(start) + 1; // It's dead.
exit:
assert(start < end && "did not find end of interval?");
LiveRange LR(start, end, interval.getNextValue(isLiveIn ? ~0U : start));
LiveRange LR(start, end, interval.getNextValue(SrcReg != 0 ? start : ~0U,
SrcReg));
interval.addRange(LR);
DEBUG(std::cerr << " +" << LR << '\n');
}
@ -568,9 +583,12 @@ void LiveIntervals::handleRegisterDef(MachineBasicBlock *MBB,
if (MRegisterInfo::isVirtualRegister(reg))
handleVirtualRegisterDef(MBB, MI, getOrCreateInterval(reg));
else if (allocatableRegs_[reg]) {
handlePhysicalRegisterDef(MBB, MI, getOrCreateInterval(reg));
unsigned SrcReg, DstReg;
if (!tii_->isMoveInstr(*MI, SrcReg, DstReg))
SrcReg = 0;
handlePhysicalRegisterDef(MBB, MI, getOrCreateInterval(reg), SrcReg);
for (const unsigned* AS = mri_->getAliasSet(reg); *AS; ++AS)
handlePhysicalRegisterDef(MBB, MI, getOrCreateInterval(*AS), true);
handlePhysicalRegisterDef(MBB, MI, getOrCreateInterval(*AS), 0);
}
}
@ -652,24 +670,17 @@ bool LiveIntervals::AdjustCopiesBackFrom(LiveInterval &IntA, LiveInterval &IntB,
// If AValNo is defined as a copy from IntB, we can potentially process this.
// Get the instruction that defines this value number.
unsigned AValNoInstIdx = IntA.getInstForValNum(AValNo);
// If it's unknown, ignore it.
if (AValNoInstIdx == ~0U || AValNoInstIdx == ~1U) return false;
// Otherwise, get the instruction for it.
MachineInstr *AValNoInstMI = getInstructionFromIndex(AValNoInstIdx);
unsigned SrcReg = IntA.getSrcRegForValNum(AValNo);
if (!SrcReg) return false; // Not defined by a copy.
// If the value number is not defined by a copy instruction, ignore it.
unsigned SrcReg, DstReg;
if (!tii_->isMoveInstr(*AValNoInstMI, SrcReg, DstReg))
return false;
// If the source register comes from an interval other than IntB, we can't
// handle this.
assert(rep(DstReg) == IntA.reg && "Not defining a reg in IntA?");
if (rep(SrcReg) != IntB.reg) return false;
// Get the LiveRange in IntB that this value number starts with.
unsigned AValNoInstIdx = IntA.getInstForValNum(AValNo);
LiveInterval::iterator ValLR = IntB.FindLiveRangeContaining(AValNoInstIdx-1);
// Make sure that the end of the live range is inside the same block as
@ -687,7 +698,7 @@ bool LiveIntervals::AdjustCopiesBackFrom(LiveInterval &IntA, LiveInterval &IntB,
// We are about to delete CopyMI, so need to remove it as the 'instruction
// that defines this value #'.
IntB.setInstDefiningValNum(BValNo, ~0U);
IntB.setValueNumberInfo(BValNo, std::make_pair(~0U, 0));
// Okay, we can merge them. We need to insert a new liverange:
// [ValLR.end, BLR.begin) of either value number, then we merge the
@ -701,7 +712,7 @@ bool LiveIntervals::AdjustCopiesBackFrom(LiveInterval &IntA, LiveInterval &IntB,
for (const unsigned *AS = mri_->getAliasSet(IntB.reg); *AS; ++AS) {
LiveInterval &AliasLI = getInterval(*AS);
AliasLI.addRange(LiveRange(FillerStart, FillerEnd,
AliasLI.getNextValue(~0U)));
AliasLI.getNextValue(~0U, 0)));
}
}
@ -832,7 +843,8 @@ bool LiveIntervals::JoinCopy(MachineInstr *CopyMI,
/// contains the value number the copy is from.
///
static unsigned ComputeUltimateVN(unsigned VN,
SmallVector<unsigned, 16> &InstDefiningValue,
SmallVector<std::pair<unsigned,
unsigned>, 16> &ValueNumberInfo,
SmallVector<int, 16> &ThisFromOther,
SmallVector<int, 16> &OtherFromThis,
SmallVector<int, 16> &ThisValNoAssignments,
@ -847,8 +859,8 @@ static unsigned ComputeUltimateVN(unsigned VN,
// number in the destination.
int OtherValNo = ThisFromOther[VN];
if (OtherValNo == -1) {
InstDefiningValue.push_back(ThisLI.getInstForValNum(VN));
return ThisValNoAssignments[VN] = InstDefiningValue.size()-1;
ValueNumberInfo.push_back(ThisLI.getValNumInfo(VN));
return ThisValNoAssignments[VN] = ValueNumberInfo.size()-1;
}
// Otherwise, this *is* a copy from the RHS. Mark this value number as
@ -856,7 +868,7 @@ static unsigned ComputeUltimateVN(unsigned VN,
// value is.
ThisValNoAssignments[VN] = -2;
unsigned UltimateVN =
ComputeUltimateVN(OtherValNo, InstDefiningValue,
ComputeUltimateVN(OtherValNo, ValueNumberInfo,
OtherFromThis, ThisFromOther,
OtherValNoAssignments, ThisValNoAssignments,
OtherLI, ThisLI);
@ -875,24 +887,17 @@ bool LiveIntervals::JoinIntervals(LiveInterval &LHS, LiveInterval &RHS) {
SmallVector<int, 16> LHSValsDefinedFromRHS;
LHSValsDefinedFromRHS.resize(LHS.getNumValNums(), -1);
for (unsigned VN = 0, e = LHS.getNumValNums(); VN != e; ++VN) {
unsigned ValInst = LHS.getInstForValNum(VN);
if (ValInst == ~0U || ValInst == ~1U)
unsigned ValSrcReg = LHS.getSrcRegForValNum(VN);
if (ValSrcReg == 0) // Src not defined by a copy?
continue;
// If the instruction defining the LHS's value is a copy.
MachineInstr *ValInstMI = getInstructionFromIndex(ValInst);
// If the value number is not defined by a copy instruction, ignore it.
unsigned SrcReg, DstReg;
if (!tii_->isMoveInstr(*ValInstMI, SrcReg, DstReg))
continue;
// DstReg is known to be a register in the LHS interval. If the src is from
// the RHS interval, we can use its value #.
if (rep(SrcReg) != RHS.reg)
if (rep(ValSrcReg) != RHS.reg)
continue;
// Figure out the value # from the RHS.
unsigned ValInst = LHS.getInstForValNum(VN);
LHSValsDefinedFromRHS[VN] = RHS.getLiveRangeContaining(ValInst-1)->ValId;
}
@ -901,24 +906,17 @@ bool LiveIntervals::JoinIntervals(LiveInterval &LHS, LiveInterval &RHS) {
SmallVector<int, 16> RHSValsDefinedFromLHS;
RHSValsDefinedFromLHS.resize(RHS.getNumValNums(), -1);
for (unsigned VN = 0, e = RHS.getNumValNums(); VN != e; ++VN) {
unsigned ValInst = RHS.getInstForValNum(VN);
if (ValInst == ~0U || ValInst == ~1U)
continue;
// If the instruction defining the RHS's value is a copy.
MachineInstr *ValInstMI = getInstructionFromIndex(ValInst);
// If the value number is not defined by a copy instruction, ignore it.
unsigned SrcReg, DstReg;
if (!tii_->isMoveInstr(*ValInstMI, SrcReg, DstReg))
unsigned ValSrcReg = RHS.getSrcRegForValNum(VN);
if (ValSrcReg == 0) // Src not defined by a copy?
continue;
// DstReg is known to be a register in the RHS interval. If the src is from
// the LHS interval, we can use its value #.
if (rep(SrcReg) != LHS.reg)
if (rep(ValSrcReg) != LHS.reg)
continue;
// Figure out the value # from the LHS.
unsigned ValInst = RHS.getInstForValNum(VN);
RHSValsDefinedFromLHS[VN] = LHS.getLiveRangeContaining(ValInst-1)->ValId;
}
@ -926,20 +924,20 @@ bool LiveIntervals::JoinIntervals(LiveInterval &LHS, LiveInterval &RHS) {
// assuming that the live ranges can be coallesced.
SmallVector<int, 16> LHSValNoAssignments;
SmallVector<int, 16> RHSValNoAssignments;
SmallVector<unsigned, 16> InstDefiningValue;
SmallVector<std::pair<unsigned,unsigned>, 16> ValueNumberInfo;
LHSValNoAssignments.resize(LHS.getNumValNums(), -1);
RHSValNoAssignments.resize(RHS.getNumValNums(), -1);
// Compute ultimate value numbers for the LHS and RHS values.
for (unsigned VN = 0, e = LHS.getNumValNums(); VN != e; ++VN) {
if (LHS.getInstForValNum(VN) == ~2U) continue;
ComputeUltimateVN(VN, InstDefiningValue,
ComputeUltimateVN(VN, ValueNumberInfo,
LHSValsDefinedFromRHS, RHSValsDefinedFromLHS,
LHSValNoAssignments, RHSValNoAssignments, LHS, RHS);
}
for (unsigned VN = 0, e = RHS.getNumValNums(); VN != e; ++VN) {
if (RHS.getInstForValNum(VN) == ~2U) continue;
ComputeUltimateVN(VN, InstDefiningValue,
ComputeUltimateVN(VN, ValueNumberInfo,
RHSValsDefinedFromLHS, LHSValsDefinedFromRHS,
RHSValNoAssignments, LHSValNoAssignments, RHS, LHS);
}
@ -989,7 +987,7 @@ bool LiveIntervals::JoinIntervals(LiveInterval &LHS, LiveInterval &RHS) {
// If we get here, we know that we can coallesce the live ranges. Ask the
// intervals to coallesce themselves now.
LHS.join(RHS, &LHSValNoAssignments[0], &RHSValNoAssignments[0],
InstDefiningValue);
ValueNumberInfo);
return true;
}