aboutsummaryrefslogtreecommitdiff
path: root/lib/CodeGen/TwoAddressInstructionPass.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'lib/CodeGen/TwoAddressInstructionPass.cpp')
-rw-r--r--lib/CodeGen/TwoAddressInstructionPass.cpp324
1 files changed, 243 insertions, 81 deletions
diff --git a/lib/CodeGen/TwoAddressInstructionPass.cpp b/lib/CodeGen/TwoAddressInstructionPass.cpp
index 8e6f809747..26c5fe4dcb 100644
--- a/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -67,7 +67,6 @@ class TwoAddressInstructionPass : public MachineFunctionPass {
const InstrItineraryData *InstrItins;
MachineRegisterInfo *MRI;
LiveVariables *LV;
- SlotIndexes *Indexes;
LiveIntervals *LIS;
AliasAnalysis *AA;
CodeGenOpt::Level OptLevel;
@@ -121,7 +120,7 @@ class TwoAddressInstructionPass : public MachineFunctionPass {
bool tryInstructionTransform(MachineBasicBlock::iterator &mi,
MachineBasicBlock::iterator &nmi,
unsigned SrcIdx, unsigned DstIdx,
- unsigned Dist);
+ unsigned Dist, bool shouldOnlyCommute);
void scanUses(unsigned DstReg);
@@ -164,6 +163,8 @@ INITIALIZE_PASS_END(TwoAddressInstructionPass, "twoaddressinstruction",
char &llvm::TwoAddressInstructionPassID = TwoAddressInstructionPass::ID;
+static bool isPlainlyKilled(MachineInstr *MI, unsigned Reg, LiveIntervals *LIS);
+
/// sink3AddrInstruction - A two-address instruction has been converted to a
/// three-address instruction to avoid clobbering a register. Try to sink it
/// past the instruction that would kill the above mentioned register to reduce
@@ -205,14 +206,29 @@ sink3AddrInstruction(MachineInstr *MI, unsigned SavedReg,
// Find the instruction that kills SavedReg.
MachineInstr *KillMI = NULL;
- for (MachineRegisterInfo::use_nodbg_iterator
- UI = MRI->use_nodbg_begin(SavedReg),
- UE = MRI->use_nodbg_end(); UI != UE; ++UI) {
- MachineOperand &UseMO = UI.getOperand();
- if (!UseMO.isKill())
- continue;
- KillMI = UseMO.getParent();
- break;
+ if (LIS) {
+ LiveInterval &LI = LIS->getInterval(SavedReg);
+ assert(LI.end() != LI.begin() &&
+ "Reg should not have empty live interval.");
+
+ SlotIndex MBBEndIdx = LIS->getMBBEndIdx(MBB).getPrevSlot();
+ LiveInterval::const_iterator I = LI.find(MBBEndIdx);
+ if (I != LI.end() && I->start < MBBEndIdx)
+ return false;
+
+ --I;
+ KillMI = LIS->getInstructionFromIndex(I->end);
+ }
+ if (!KillMI) {
+ for (MachineRegisterInfo::use_nodbg_iterator
+ UI = MRI->use_nodbg_begin(SavedReg),
+ UE = MRI->use_nodbg_end(); UI != UE; ++UI) {
+ MachineOperand &UseMO = UI.getOperand();
+ if (!UseMO.isKill())
+ continue;
+ KillMI = UseMO.getParent();
+ break;
+ }
}
// If we find the instruction that kills SavedReg, and it is in an
@@ -251,7 +267,7 @@ sink3AddrInstruction(MachineInstr *MI, unsigned SavedReg,
if (DefReg == MOReg)
return false;
- if (MO.isKill()) {
+ if (MO.isKill() || (LIS && isPlainlyKilled(OtherMI, MOReg, LIS))) {
if (OtherMI == KillMI && MOReg == SavedReg)
// Save the operand that kills the register. We want to unset the kill
// marker if we can sink MI past it.
@@ -264,13 +280,15 @@ sink3AddrInstruction(MachineInstr *MI, unsigned SavedReg,
}
assert(KillMO && "Didn't find kill");
- // Update kill and LV information.
- KillMO->setIsKill(false);
- KillMO = MI->findRegisterUseOperand(SavedReg, false, TRI);
- KillMO->setIsKill(true);
+ if (!LIS) {
+ // Update kill and LV information.
+ KillMO->setIsKill(false);
+ KillMO = MI->findRegisterUseOperand(SavedReg, false, TRI);
+ KillMO->setIsKill(true);
- if (LV)
- LV->replaceKillInstruction(SavedReg, KillMI, MI);
+ if (LV)
+ LV->replaceKillInstruction(SavedReg, KillMI, MI);
+ }
// Move instruction to its destination.
MBB->remove(MI);
@@ -331,6 +349,33 @@ static bool isCopyToReg(MachineInstr &MI, const TargetInstrInfo *TII,
return true;
}
+/// isPLainlyKilled - Test if the given register value, which is used by the
+// given instruction, is killed by the given instruction.
+static bool isPlainlyKilled(MachineInstr *MI, unsigned Reg,
+ LiveIntervals *LIS) {
+ if (LIS && TargetRegisterInfo::isVirtualRegister(Reg) &&
+ !LIS->isNotInMIMap(MI)) {
+ // FIXME: Sometimes tryInstructionTransform() will add instructions and
+ // test whether they can be folded before keeping them. In this case it
+ // sets a kill before recursively calling tryInstructionTransform() again.
+ // If there is no interval available, we assume that this instruction is
+ // one of those. A kill flag is manually inserted on the operand so the
+ // check below will handle it.
+ LiveInterval &LI = LIS->getInterval(Reg);
+ // This is to match the kill flag version where undefs don't have kill
+ // flags.
+ if (!LI.hasAtLeastOneValue())
+ return false;
+
+ SlotIndex useIdx = LIS->getInstructionIndex(MI);
+ LiveInterval::const_iterator I = LI.find(useIdx);
+ assert(I != LI.end() && "Reg must be live-in to use.");
+ return !I->end.isBlock() && SlotIndex::isSameInstr(I->end, useIdx);
+ }
+
+ return MI->killsRegister(Reg);
+}
+
/// isKilled - Test if the given register value, which is used by the given
/// instruction, is killed by the given instruction. This looks through
/// coalescable copies to see if the original value is potentially not killed.
@@ -346,12 +391,20 @@ static bool isCopyToReg(MachineInstr &MI, const TargetInstrInfo *TII,
/// normal heuristics commute the (two-address) add, which lets
/// coalescing eliminate the extra copy.
///
+/// If allowFalsePositives is true then likely kills are treated as kills even
+/// if it can't be proven that they are kills.
static bool isKilled(MachineInstr &MI, unsigned Reg,
const MachineRegisterInfo *MRI,
- const TargetInstrInfo *TII) {
+ const TargetInstrInfo *TII,
+ LiveIntervals *LIS,
+ bool allowFalsePositives) {
MachineInstr *DefMI = &MI;
for (;;) {
- if (!DefMI->killsRegister(Reg))
+ // All uses of physical registers are likely to be kills.
+ if (TargetRegisterInfo::isPhysicalRegister(Reg) &&
+ (allowFalsePositives || MRI->hasOneUse(Reg)))
+ return true;
+ if (!isPlainlyKilled(DefMI, Reg, LIS))
return false;
if (TargetRegisterInfo::isPhysicalRegister(Reg))
return true;
@@ -472,7 +525,7 @@ isProfitableToCommute(unsigned regA, unsigned regB, unsigned regC,
// insert => %reg1030<def> = MOV8rr %reg1029
// %reg1030<def> = ADD8rr %reg1029<kill>, %reg1028<kill>, %EFLAGS<imp-def,dead>
- if (!MI->killsRegister(regC))
+ if (!isPlainlyKilled(MI, regC, LIS))
return false;
// Ok, we have something like:
@@ -528,19 +581,9 @@ commuteInstruction(MachineBasicBlock::iterator &mi,
}
DEBUG(dbgs() << "2addr: COMMUTED TO: " << *NewMI);
- // If the instruction changed to commute it, update livevar.
- if (NewMI != MI) {
- if (LV)
- // Update live variables
- LV->replaceKillInstruction(RegC, MI, NewMI);
- if (Indexes)
- Indexes->replaceMachineInstrInMaps(MI, NewMI);
-
- MBB->insert(mi, NewMI); // Insert the new inst
- MBB->erase(mi); // Nuke the old inst.
- mi = NewMI;
- DistanceMap.insert(std::make_pair(NewMI, Dist));
- }
+ assert(NewMI == MI &&
+ "TargetInstrInfo::commuteInstruction() should not return a new "
+ "instruction unless it was requested.");
// Update source register map.
unsigned FromRegC = getMappedReg(RegC, SrcRegMap);
@@ -587,8 +630,8 @@ TwoAddressInstructionPass::convertInstTo3Addr(MachineBasicBlock::iterator &mi,
DEBUG(dbgs() << "2addr: TO 3-ADDR: " << *NewMI);
bool Sunk = false;
- if (Indexes)
- Indexes->replaceMachineInstrInMaps(mi, NewMI);
+ if (LIS)
+ LIS->ReplaceMachineInstrInMaps(mi, NewMI);
if (NewMI->findRegisterUseOperand(RegB, false, TRI))
// FIXME: Temporary workaround. If the new instruction doesn't
@@ -700,9 +743,9 @@ bool TwoAddressInstructionPass::
rescheduleMIBelowKill(MachineBasicBlock::iterator &mi,
MachineBasicBlock::iterator &nmi,
unsigned Reg) {
- // Bail immediately if we don't have LV available. We use it to find kills
- // efficiently.
- if (!LV)
+ // Bail immediately if we don't have LV or LIS available. We use them to find
+ // kills efficiently.
+ if (!LV && !LIS)
return false;
MachineInstr *MI = &*mi;
@@ -711,7 +754,22 @@ rescheduleMIBelowKill(MachineBasicBlock::iterator &mi,
// Must be created from unfolded load. Don't waste time trying this.
return false;
- MachineInstr *KillMI = LV->getVarInfo(Reg).findKill(MBB);
+ MachineInstr *KillMI = 0;
+ if (LIS) {
+ LiveInterval &LI = LIS->getInterval(Reg);
+ assert(LI.end() != LI.begin() &&
+ "Reg should not have empty live interval.");
+
+ SlotIndex MBBEndIdx = LIS->getMBBEndIdx(MBB).getPrevSlot();
+ LiveInterval::const_iterator I = LI.find(MBBEndIdx);
+ if (I != LI.end() && I->start < MBBEndIdx)
+ return false;
+
+ --I;
+ KillMI = LIS->getInstructionFromIndex(I->end);
+ } else {
+ KillMI = LV->getVarInfo(Reg).findKill(MBB);
+ }
if (!KillMI || MI == KillMI || KillMI->isCopy() || KillMI->isCopyLike())
// Don't mess with copies, they may be coalesced later.
return false;
@@ -747,24 +805,27 @@ rescheduleMIBelowKill(MachineBasicBlock::iterator &mi,
Defs.insert(MOReg);
else {
Uses.insert(MOReg);
- if (MO.isKill() && MOReg != Reg)
+ if (MOReg != Reg && (MO.isKill() ||
+ (LIS && isPlainlyKilled(MI, MOReg, LIS))))
Kills.insert(MOReg);
}
}
// Move the copies connected to MI down as well.
- MachineBasicBlock::iterator From = MI;
- MachineBasicBlock::iterator To = llvm::next(From);
- while (To->isCopy() && Defs.count(To->getOperand(1).getReg())) {
- Defs.insert(To->getOperand(0).getReg());
- ++To;
+ MachineBasicBlock::iterator Begin = MI;
+ MachineBasicBlock::iterator AfterMI = llvm::next(Begin);
+
+ MachineBasicBlock::iterator End = AfterMI;
+ while (End->isCopy() && Defs.count(End->getOperand(1).getReg())) {
+ Defs.insert(End->getOperand(0).getReg());
+ ++End;
}
// Check if the reschedule will not break depedencies.
unsigned NumVisited = 0;
MachineBasicBlock::iterator KillPos = KillMI;
++KillPos;
- for (MachineBasicBlock::iterator I = To; I != KillPos; ++I) {
+ for (MachineBasicBlock::iterator I = End; I != KillPos; ++I) {
MachineInstr *OtherMI = I;
// DBG_VALUE cannot be counted against the limit.
if (OtherMI->isDebugValue())
@@ -795,11 +856,13 @@ rescheduleMIBelowKill(MachineBasicBlock::iterator &mi,
} else {
if (Defs.count(MOReg))
return false;
+ bool isKill = MO.isKill() ||
+ (LIS && isPlainlyKilled(OtherMI, MOReg, LIS));
if (MOReg != Reg &&
- ((MO.isKill() && Uses.count(MOReg)) || Kills.count(MOReg)))
+ ((isKill && Uses.count(MOReg)) || Kills.count(MOReg)))
// Don't want to extend other live ranges and update kills.
return false;
- if (MOReg == Reg && !MO.isKill())
+ if (MOReg == Reg && !isKill)
// We can't schedule across a use of the register in question.
return false;
// Ensure that if this is register in question, its the kill we expect.
@@ -810,19 +873,35 @@ rescheduleMIBelowKill(MachineBasicBlock::iterator &mi,
}
// Move debug info as well.
- while (From != MBB->begin() && llvm::prior(From)->isDebugValue())
- --From;
+ while (Begin != MBB->begin() && llvm::prior(Begin)->isDebugValue())
+ --Begin;
+
+ nmi = End;
+ MachineBasicBlock::iterator InsertPos = KillPos;
+ if (LIS) {
+ // We have to move the copies first so that the MBB is still well-formed
+ // when calling handleMove().
+ for (MachineBasicBlock::iterator MBBI = AfterMI; MBBI != End;) {
+ MachineInstr *CopyMI = MBBI;
+ ++MBBI;
+ MBB->splice(InsertPos, MBB, CopyMI);
+ LIS->handleMove(CopyMI);
+ InsertPos = CopyMI;
+ }
+ End = llvm::next(MachineBasicBlock::iterator(MI));
+ }
// Copies following MI may have been moved as well.
- nmi = To;
- MBB->splice(KillPos, MBB, From, To);
+ MBB->splice(InsertPos, MBB, Begin, End);
DistanceMap.erase(DI);
// Update live variables
- LV->removeVirtualRegisterKilled(Reg, KillMI);
- LV->addVirtualRegisterKilled(Reg, MI);
- if (LIS)
+ if (LIS) {
LIS->handleMove(MI);
+ } else {
+ LV->removeVirtualRegisterKilled(Reg, KillMI);
+ LV->addVirtualRegisterKilled(Reg, MI);
+ }
DEBUG(dbgs() << "\trescheduled below kill: " << *KillMI);
return true;
@@ -858,9 +937,9 @@ bool TwoAddressInstructionPass::
rescheduleKillAboveMI(MachineBasicBlock::iterator &mi,
MachineBasicBlock::iterator &nmi,
unsigned Reg) {
- // Bail immediately if we don't have LV available. We use it to find kills
- // efficiently.
- if (!LV)
+ // Bail immediately if we don't have LV or LIS available. We use them to find
+ // kills efficiently.
+ if (!LV && !LIS)
return false;
MachineInstr *MI = &*mi;
@@ -869,7 +948,22 @@ rescheduleKillAboveMI(MachineBasicBlock::iterator &mi,
// Must be created from unfolded load. Don't waste time trying this.
return false;
- MachineInstr *KillMI = LV->getVarInfo(Reg).findKill(MBB);
+ MachineInstr *KillMI = 0;
+ if (LIS) {
+ LiveInterval &LI = LIS->getInterval(Reg);
+ assert(LI.end() != LI.begin() &&
+ "Reg should not have empty live interval.");
+
+ SlotIndex MBBEndIdx = LIS->getMBBEndIdx(MBB).getPrevSlot();
+ LiveInterval::const_iterator I = LI.find(MBBEndIdx);
+ if (I != LI.end() && I->start < MBBEndIdx)
+ return false;
+
+ --I;
+ KillMI = LIS->getInstructionFromIndex(I->end);
+ } else {
+ KillMI = LV->getVarInfo(Reg).findKill(MBB);
+ }
if (!KillMI || MI == KillMI || KillMI->isCopy() || KillMI->isCopyLike())
// Don't mess with copies, they may be coalesced later.
return false;
@@ -896,10 +990,11 @@ rescheduleKillAboveMI(MachineBasicBlock::iterator &mi,
continue;
if (isDefTooClose(MOReg, DI->second, MI))
return false;
- if (MOReg == Reg && !MO.isKill())
+ bool isKill = MO.isKill() || (LIS && isPlainlyKilled(KillMI, MOReg, LIS));
+ if (MOReg == Reg && !isKill)
return false;
Uses.insert(MOReg);
- if (MO.isKill() && MOReg != Reg)
+ if (isKill && MOReg != Reg)
Kills.insert(MOReg);
} else if (TargetRegisterInfo::isPhysicalRegister(MOReg)) {
Defs.insert(MOReg);
@@ -939,7 +1034,8 @@ rescheduleKillAboveMI(MachineBasicBlock::iterator &mi,
if (Kills.count(MOReg))
// Don't want to extend other live ranges and update kills.
return false;
- if (OtherMI != MI && MOReg == Reg && !MO.isKill())
+ if (OtherMI != MI && MOReg == Reg &&
+ !(MO.isKill() || (LIS && isPlainlyKilled(OtherMI, MOReg, LIS))))
// We can't schedule across a use of the register in question.
return false;
} else {
@@ -973,10 +1069,12 @@ rescheduleKillAboveMI(MachineBasicBlock::iterator &mi,
DistanceMap.erase(DI);
// Update live variables
- LV->removeVirtualRegisterKilled(Reg, KillMI);
- LV->addVirtualRegisterKilled(Reg, MI);
- if (LIS)
+ if (LIS) {
LIS->handleMove(KillMI);
+ } else {
+ LV->removeVirtualRegisterKilled(Reg, KillMI);
+ LV->addVirtualRegisterKilled(Reg, MI);
+ }
DEBUG(dbgs() << "\trescheduled kill: " << *KillMI);
return true;
@@ -987,11 +1085,13 @@ rescheduleKillAboveMI(MachineBasicBlock::iterator &mi,
/// either eliminate the tied operands or improve the opportunities for
/// coalescing away the register copy. Returns true if no copy needs to be
/// inserted to untie mi's operands (either because they were untied, or
-/// because mi was rescheduled, and will be visited again later).
+/// because mi was rescheduled, and will be visited again later). If the
+/// shouldOnlyCommute flag is true, only instruction commutation is attempted.
bool TwoAddressInstructionPass::
tryInstructionTransform(MachineBasicBlock::iterator &mi,
MachineBasicBlock::iterator &nmi,
- unsigned SrcIdx, unsigned DstIdx, unsigned Dist) {
+ unsigned SrcIdx, unsigned DstIdx,
+ unsigned Dist, bool shouldOnlyCommute) {
if (OptLevel == CodeGenOpt::None)
return false;
@@ -1001,7 +1101,7 @@ tryInstructionTransform(MachineBasicBlock::iterator &mi,
assert(TargetRegisterInfo::isVirtualRegister(regB) &&
"cannot make instruction into two-address form");
- bool regBKilled = isKilled(MI, regB, MRI, TII);
+ bool regBKilled = isKilled(MI, regB, MRI, TII, LIS, true);
if (TargetRegisterInfo::isVirtualRegister(regA))
scanUses(regA);
@@ -1021,7 +1121,7 @@ tryInstructionTransform(MachineBasicBlock::iterator &mi,
if (regCIdx != ~0U) {
regC = MI.getOperand(regCIdx).getReg();
- if (!regBKilled && isKilled(MI, regC, MRI, TII))
+ if (!regBKilled && isKilled(MI, regC, MRI, TII, LIS, false))
// If C dies but B does not, swap the B and C operands.
// This makes the live ranges of A and C joinable.
TryCommute = true;
@@ -1040,6 +1140,9 @@ tryInstructionTransform(MachineBasicBlock::iterator &mi,
return false;
}
+ if (shouldOnlyCommute)
+ return false;
+
// If there is one more use of regB later in the same MBB, consider
// re-schedule this MI below it.
if (rescheduleMIBelowKill(mi, nmi, regB)) {
@@ -1115,10 +1218,12 @@ tryInstructionTransform(MachineBasicBlock::iterator &mi,
unsigned NewDstIdx = NewMIs[1]->findRegisterDefOperandIdx(regA);
unsigned NewSrcIdx = NewMIs[1]->findRegisterUseOperandIdx(regB);
MachineBasicBlock::iterator NewMI = NewMIs[1];
- bool TransformSuccess =
- tryInstructionTransform(NewMI, mi, NewSrcIdx, NewDstIdx, Dist);
- if (TransformSuccess ||
- NewMIs[1]->getOperand(NewSrcIdx).isKill()) {
+ bool TransformResult =
+ tryInstructionTransform(NewMI, mi, NewSrcIdx, NewDstIdx, Dist, true);
+ (void)TransformResult;
+ assert(!TransformResult &&
+ "tryInstructionTransform() should return false.");
+ if (NewMIs[1]->getOperand(NewSrcIdx).isKill()) {
// Success, or at least we made an improvement. Keep the unfolded
// instructions and discard the original.
if (LV) {
@@ -1149,10 +1254,26 @@ tryInstructionTransform(MachineBasicBlock::iterator &mi,
}
LV->addVirtualRegisterKilled(Reg, NewMIs[1]);
}
+
+ SmallVector<unsigned, 4> OrigRegs;
+ if (LIS) {
+ for (MachineInstr::const_mop_iterator MOI = MI.operands_begin(),
+ MOE = MI.operands_end(); MOI != MOE; ++MOI) {
+ if (MOI->isReg())
+ OrigRegs.push_back(MOI->getReg());
+ }
+ }
+
MI.eraseFromParent();
+
+ // Update LiveIntervals.
+ if (LIS) {
+ MachineBasicBlock::iterator Begin(NewMIs[0]);
+ MachineBasicBlock::iterator End(NewMIs[1]);
+ LIS->repairIntervalsInRange(MBB, Begin, End, OrigRegs);
+ }
+
mi = NewMIs[1];
- if (TransformSuccess)
- return true;
} else {
// Transforming didn't eliminate the tie and didn't lead to an
// improvement. Clean up the unfolded instructions and keep the
@@ -1215,9 +1336,15 @@ TwoAddressInstructionPass::processTiedPairs(MachineInstr *MI,
TiedPairList &TiedPairs,
unsigned &Dist) {
bool IsEarlyClobber = false;
+ for (unsigned tpi = 0, tpe = TiedPairs.size(); tpi != tpe; ++tpi) {
+ const MachineOperand &DstMO = MI->getOperand(TiedPairs[tpi].second);
+ IsEarlyClobber |= DstMO.isEarlyClobber();
+ }
+
bool RemovedKillFlag = false;
bool AllUsesCopied = true;
unsigned LastCopiedReg = 0;
+ SlotIndex LastCopyIdx;
unsigned RegB = 0;
for (unsigned tpi = 0, tpe = TiedPairs.size(); tpi != tpe; ++tpi) {
unsigned SrcIdx = TiedPairs[tpi].first;
@@ -1225,7 +1352,6 @@ TwoAddressInstructionPass::processTiedPairs(MachineInstr *MI,
const MachineOperand &DstMO = MI->getOperand(DstIdx);
unsigned RegA = DstMO.getReg();
- IsEarlyClobber |= DstMO.isEarlyClobber();
// Grab RegB from the instruction because it may have changed if the
// instruction was commuted.
@@ -1263,9 +1389,17 @@ TwoAddressInstructionPass::processTiedPairs(MachineInstr *MI,
DistanceMap.insert(std::make_pair(PrevMI, Dist));
DistanceMap[MI] = ++Dist;
- SlotIndex CopyIdx;
- if (Indexes)
- CopyIdx = Indexes->insertMachineInstrInMaps(PrevMI).getRegSlot();
+ if (LIS) {
+ LastCopyIdx = LIS->InsertMachineInstrInMaps(PrevMI).getRegSlot();
+
+ if (TargetRegisterInfo::isVirtualRegister(RegA)) {
+ LiveInterval &LI = LIS->getInterval(RegA);
+ VNInfo *VNI = LI.getNextValue(LastCopyIdx, LIS->getVNInfoAllocator());
+ SlotIndex endIdx =
+ LIS->getInstructionIndex(MI).getRegSlot(IsEarlyClobber);
+ LI.addRange(LiveRange(LastCopyIdx, endIdx, VNI));
+ }
+ }
DEBUG(dbgs() << "\t\tprepend:\t" << *PrevMI);
@@ -1311,6 +1445,18 @@ TwoAddressInstructionPass::processTiedPairs(MachineInstr *MI,
LV->addVirtualRegisterKilled(RegB, PrevMI);
}
+ // Update LiveIntervals.
+ if (LIS) {
+ LiveInterval &LI = LIS->getInterval(RegB);
+ SlotIndex MIIdx = LIS->getInstructionIndex(MI);
+ LiveInterval::const_iterator I = LI.find(MIIdx);
+ assert(I != LI.end() && "RegB must be live-in to use.");
+
+ SlotIndex UseIdx = MIIdx.getRegSlot(IsEarlyClobber);
+ if (I->end == UseIdx)
+ LI.removeRange(LastCopyIdx, UseIdx);
+ }
+
} else if (RemovedKillFlag) {
// Some tied uses of regB matched their destination registers, so
// regB is still used in this instruction, but a kill flag was
@@ -1335,7 +1481,6 @@ bool TwoAddressInstructionPass::runOnMachineFunction(MachineFunction &Func) {
TII = TM.getInstrInfo();
TRI = TM.getRegisterInfo();
InstrItins = TM.getInstrItineraryData();
- Indexes = getAnalysisIfAvailable<SlotIndexes>();
LV = getAnalysisIfAvailable<LiveVariables>();
LIS = getAnalysisIfAvailable<LiveIntervals>();
AA = &getAnalysis<AliasAnalysis>();
@@ -1399,7 +1544,7 @@ bool TwoAddressInstructionPass::runOnMachineFunction(MachineFunction &Func) {
unsigned SrcReg = mi->getOperand(SrcIdx).getReg();
unsigned DstReg = mi->getOperand(DstIdx).getReg();
if (SrcReg != DstReg &&
- tryInstructionTransform(mi, nmi, SrcIdx, DstIdx, Dist)) {
+ tryInstructionTransform(mi, nmi, SrcIdx, DstIdx, Dist, false)) {
// The tied operands have been eliminated or shifted further down the
// block to ease elimination. Continue processing with 'nmi'.
TiedOperands.clear();
@@ -1437,6 +1582,9 @@ bool TwoAddressInstructionPass::runOnMachineFunction(MachineFunction &Func) {
}
}
+ if (LIS)
+ MF->verify(this, "After two-address instruction pass");
+
return MadeChange;
}
@@ -1462,6 +1610,13 @@ eliminateRegSequence(MachineBasicBlock::iterator &MBBI) {
llvm_unreachable(0);
}
+ SmallVector<unsigned, 4> OrigRegs;
+ if (LIS) {
+ OrigRegs.push_back(MI->getOperand(0).getReg());
+ for (unsigned i = 1, e = MI->getNumOperands(); i < e; i += 2)
+ OrigRegs.push_back(MI->getOperand(i).getReg());
+ }
+
bool DefEmitted = false;
for (unsigned i = 1, e = MI->getNumOperands(); i < e; i += 2) {
MachineOperand &UseMO = MI->getOperand(i);
@@ -1505,6 +1660,9 @@ eliminateRegSequence(MachineBasicBlock::iterator &MBBI) {
DEBUG(dbgs() << "Inserted: " << *CopyMI);
}
+ MachineBasicBlock::iterator EndMBBI =
+ llvm::next(MachineBasicBlock::iterator(MI));
+
if (!DefEmitted) {
DEBUG(dbgs() << "Turned: " << *MI << " into an IMPLICIT_DEF");
MI->setDesc(TII->get(TargetOpcode::IMPLICIT_DEF));
@@ -1514,4 +1672,8 @@ eliminateRegSequence(MachineBasicBlock::iterator &MBBI) {
DEBUG(dbgs() << "Eliminated: " << *MI);
MI->eraseFromParent();
}
+
+ // Udpate LiveIntervals.
+ if (LIS)
+ LIS->repairIntervalsInRange(MBB, MBBI, EndMBBI, OrigRegs);
}
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2025-04-28 00:09:56 +0000