unsigned LembergInstrInfo::InsertBranch(MachineBasicBlock &MBB,
MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
const SmallVectorImpl<MachineOperand> &Cond,
DebugLoc DL) const {
// Shouldn't be a fall through.
assert(TBB && "InsertBranch must not be told to insert a fallthrough");
assert((Cond.size() == 2 || Cond.size() == 0) &&
"Lemberg branch conditions can only have two components!");
if (FBB == 0) { // One way branch.
if (Cond.empty()) {
// Unconditional branch?
BuildMI(&MBB, DL, get(Lemberg::JUMP)).addMBB(TBB);
} else if (Cond[1].getImm() == LembergCC::FALSE
|| Cond[1].getImm() == LembergCC::TRUE) {
BuildMI(&MBB, DL, get(Lemberg::JUMPpred))
.addOperand(Cond[1]).addOperand(Cond[0]).addMBB(TBB);
} else {
unsigned Opcode;
switch (Cond[1].getImm()) {
case LembergCC::EQZ: Opcode = Lemberg::JUMPeqz; break;
case LembergCC::NEZ: Opcode = Lemberg::JUMPnez; break;
case LembergCC::LTZ: Opcode = Lemberg::JUMPltz; break;
case LembergCC::GEZ: Opcode = Lemberg::JUMPgez; break;
case LembergCC::GTZ: Opcode = Lemberg::JUMPgtz; break;
case LembergCC::LEZ: Opcode = Lemberg::JUMPlez; break;
}
MachineInstr *MI =
BuildMI(&MBB, DL, get(Opcode)).addOperand(Cond[0]).addMBB(TBB);
MI->addRegisterDead(Lemberg::C3, &RI);
}
return 1;
} else {
// Two-way conditional branch.
if (Cond[1].getImm() == LembergCC::FALSE
|| Cond[1].getImm() == LembergCC::TRUE) {
BuildMI(&MBB, DL, get(Lemberg::JUMPpred))
.addOperand(Cond[1]).addOperand(Cond[0]).addMBB(TBB);
} else {
unsigned Opcode;
switch (Cond[1].getImm()) {
case LembergCC::EQZ: Opcode = Lemberg::JUMPeqz; break;
case LembergCC::NEZ: Opcode = Lemberg::JUMPnez; break;
case LembergCC::LTZ: Opcode = Lemberg::JUMPltz; break;
case LembergCC::GEZ: Opcode = Lemberg::JUMPgez; break;
case LembergCC::GTZ: Opcode = Lemberg::JUMPgtz; break;
case LembergCC::LEZ: Opcode = Lemberg::JUMPlez; break;
}
MachineInstr *MI =
BuildMI(&MBB, DL, get(Opcode)).addOperand(Cond[0]).addMBB(TBB);
MI->addRegisterDead(Lemberg::C3, &RI);
}
BuildMI(&MBB, DL, get(Lemberg::JUMP)).addMBB(FBB);
return 2;
}
}
void SplitEditor::deleteRematVictims() {
SmallVector<MachineInstr*, 8> Dead;
for (LiveRangeEdit::iterator I = Edit->begin(), E = Edit->end(); I != E; ++I){
LiveInterval *LI = *I;
for (LiveInterval::const_iterator LII = LI->begin(), LIE = LI->end();
LII != LIE; ++LII) {
// Dead defs end at the store slot.
if (LII->end != LII->valno->def.getNextSlot())
continue;
MachineInstr *MI = LIS.getInstructionFromIndex(LII->valno->def);
assert(MI && "Missing instruction for dead def");
MI->addRegisterDead(LI->reg, &TRI);
if (!MI->allDefsAreDead())
continue;
DEBUG(dbgs() << "All defs dead: " << *MI);
Dead.push_back(MI);
}
}
if (Dead.empty())
return;
Edit->eliminateDeadDefs(Dead, LIS, VRM, TII);
}
bool LiveRangeEdit::foldAsLoad(LiveInterval *LI,
SmallVectorImpl<MachineInstr*> &Dead) {
MachineInstr *DefMI = 0, *UseMI = 0;
// Check that there is a single def and a single use.
for (MachineRegisterInfo::reg_nodbg_iterator I = MRI.reg_nodbg_begin(LI->reg),
E = MRI.reg_nodbg_end(); I != E; ++I) {
MachineOperand &MO = I.getOperand();
MachineInstr *MI = MO.getParent();
if (MO.isDef()) {
if (DefMI && DefMI != MI)
return false;
if (!MI->canFoldAsLoad())
return false;
DefMI = MI;
} else if (!MO.isUndef()) {
if (UseMI && UseMI != MI)
return false;
// FIXME: Targets don't know how to fold subreg uses.
if (MO.getSubReg())
return false;
UseMI = MI;
}
}
if (!DefMI || !UseMI)
return false;
// Since we're moving the DefMI load, make sure we're not extending any live
// ranges.
if (!allUsesAvailableAt(DefMI,
LIS.getInstructionIndex(DefMI),
LIS.getInstructionIndex(UseMI)))
return false;
// We also need to make sure it is safe to move the load.
// Assume there are stores between DefMI and UseMI.
bool SawStore = true;
if (!DefMI->isSafeToMove(&TII, 0, SawStore))
return false;
DEBUG(dbgs() << "Try to fold single def: " << *DefMI
<< " into single use: " << *UseMI);
SmallVector<unsigned, 8> Ops;
if (UseMI->readsWritesVirtualRegister(LI->reg, &Ops).second)
return false;
MachineInstr *FoldMI = TII.foldMemoryOperand(UseMI, Ops, DefMI);
if (!FoldMI)
return false;
DEBUG(dbgs() << " folded: " << *FoldMI);
LIS.ReplaceMachineInstrInMaps(UseMI, FoldMI);
UseMI->eraseFromParent();
DefMI->addRegisterDead(LI->reg, 0);
Dead.push_back(DefMI);
++NumDCEFoldedLoads;
return true;
}
bool LiveRangeEdit::foldAsLoad(LiveInterval *LI,
SmallVectorImpl<MachineInstr*> &Dead,
MachineRegisterInfo &MRI,
LiveIntervals &LIS,
const TargetInstrInfo &TII) {
MachineInstr *DefMI = 0, *UseMI = 0;
// Check that there is a single def and a single use.
for (MachineRegisterInfo::reg_nodbg_iterator I = MRI.reg_nodbg_begin(LI->reg),
E = MRI.reg_nodbg_end(); I != E; ++I) {
MachineOperand &MO = I.getOperand();
MachineInstr *MI = MO.getParent();
if (MO.isDef()) {
if (DefMI && DefMI != MI)
return false;
if (!MI->getDesc().canFoldAsLoad())
return false;
DefMI = MI;
} else if (!MO.isUndef()) {
if (UseMI && UseMI != MI)
return false;
// FIXME: Targets don't know how to fold subreg uses.
if (MO.getSubReg())
return false;
UseMI = MI;
}
}
if (!DefMI || !UseMI)
return false;
DEBUG(dbgs() << "Try to fold single def: " << *DefMI
<< " into single use: " << *UseMI);
SmallVector<unsigned, 8> Ops;
if (UseMI->readsWritesVirtualRegister(LI->reg, &Ops).second)
return false;
MachineInstr *FoldMI = TII.foldMemoryOperand(UseMI, Ops, DefMI);
if (!FoldMI)
return false;
DEBUG(dbgs() << " folded: " << *FoldMI);
LIS.ReplaceMachineInstrInMaps(UseMI, FoldMI);
UseMI->eraseFromParent();
DefMI->addRegisterDead(LI->reg, 0);
Dead.push_back(DefMI);
++NumDCEFoldedLoads;
return true;
}
bool LiveIntervals::computeDeadValues(LiveInterval &LI,
SmallVectorImpl<MachineInstr*> *dead) {
bool PHIRemoved = false;
for (auto VNI : LI.valnos) {
if (VNI->isUnused())
continue;
SlotIndex Def = VNI->def;
LiveRange::iterator I = LI.FindSegmentContaining(Def);
assert(I != LI.end() && "Missing segment for VNI");
// Is the register live before? Otherwise we may have to add a read-undef
// flag for subregister defs.
if (MRI->tracksSubRegLiveness()) {
if ((I == LI.begin() || std::prev(I)->end < Def) && !VNI->isPHIDef()) {
MachineInstr *MI = getInstructionFromIndex(Def);
MI->addRegisterDefReadUndef(LI.reg);
}
}
if (I->end != Def.getDeadSlot())
continue;
if (VNI->isPHIDef()) {
// This is a dead PHI. Remove it.
VNI->markUnused();
LI.removeSegment(I);
DEBUG(dbgs() << "Dead PHI at " << Def << " may separate interval\n");
PHIRemoved = true;
} else {
// This is a dead def. Make sure the instruction knows.
MachineInstr *MI = getInstructionFromIndex(Def);
assert(MI && "No instruction defining live value");
MI->addRegisterDead(LI.reg, TRI);
if (dead && MI->allDefsAreDead()) {
DEBUG(dbgs() << "All defs dead: " << Def << '\t' << *MI);
dead->push_back(MI);
}
}
}
return PHIRemoved;
}
/// reMaterializeAll - Try to rematerialize as many uses as possible,
/// and trim the live ranges after.
void InlineSpiller::reMaterializeAll() {
// analyzeSiblingValues has already tested all relevant defining instructions.
if (!Edit->anyRematerializable(AA))
return;
UsedValues.clear();
// Try to remat before all uses of snippets.
bool anyRemat = false;
for (unsigned i = 0, e = RegsToSpill.size(); i != e; ++i) {
unsigned Reg = RegsToSpill[i];
LiveInterval &LI = LIS.getInterval(Reg);
for (MachineRegisterInfo::use_nodbg_iterator
RI = MRI.use_nodbg_begin(Reg);
MachineInstr *MI = RI.skipBundle();)
anyRemat |= reMaterializeFor(LI, MI);
}
if (!anyRemat)
return;
// Remove any values that were completely rematted.
for (unsigned i = 0, e = RegsToSpill.size(); i != e; ++i) {
unsigned Reg = RegsToSpill[i];
LiveInterval &LI = LIS.getInterval(Reg);
for (LiveInterval::vni_iterator I = LI.vni_begin(), E = LI.vni_end();
I != E; ++I) {
VNInfo *VNI = *I;
if (VNI->isUnused() || VNI->isPHIDef() || UsedValues.count(VNI))
continue;
MachineInstr *MI = LIS.getInstructionFromIndex(VNI->def);
MI->addRegisterDead(Reg, &TRI);
if (!MI->allDefsAreDead())
continue;
DEBUG(dbgs() << "All defs dead: " << *MI);
DeadDefs.push_back(MI);
}
}
// Eliminate dead code after remat. Note that some snippet copies may be
// deleted here.
if (DeadDefs.empty())
return;
DEBUG(dbgs() << "Remat created " << DeadDefs.size() << " dead defs.\n");
Edit->eliminateDeadDefs(DeadDefs, RegsToSpill);
// Get rid of deleted and empty intervals.
unsigned ResultPos = 0;
for (unsigned i = 0, e = RegsToSpill.size(); i != e; ++i) {
unsigned Reg = RegsToSpill[i];
if (!LIS.hasInterval(Reg))
continue;
LiveInterval &LI = LIS.getInterval(Reg);
if (LI.empty()) {
Edit->eraseVirtReg(Reg);
continue;
}
RegsToSpill[ResultPos++] = Reg;
}
RegsToSpill.erase(RegsToSpill.begin() + ResultPos, RegsToSpill.end());
DEBUG(dbgs() << RegsToSpill.size() << " registers to spill after remat.\n");
}
void VirtRegRewriter::rewrite() {
bool NoSubRegLiveness = !MRI->subRegLivenessEnabled();
SmallVector<unsigned, 8> SuperDeads;
SmallVector<unsigned, 8> SuperDefs;
SmallVector<unsigned, 8> SuperKills;
for (MachineFunction::iterator MBBI = MF->begin(), MBBE = MF->end();
MBBI != MBBE; ++MBBI) {
DEBUG(MBBI->print(dbgs(), Indexes));
for (MachineBasicBlock::instr_iterator
MII = MBBI->instr_begin(), MIE = MBBI->instr_end(); MII != MIE;) {
MachineInstr *MI = &*MII;
++MII;
for (MachineInstr::mop_iterator MOI = MI->operands_begin(),
MOE = MI->operands_end(); MOI != MOE; ++MOI) {
MachineOperand &MO = *MOI;
// Make sure MRI knows about registers clobbered by regmasks.
if (MO.isRegMask())
MRI->addPhysRegsUsedFromRegMask(MO.getRegMask());
if (!MO.isReg() || !TargetRegisterInfo::isVirtualRegister(MO.getReg()))
continue;
unsigned VirtReg = MO.getReg();
unsigned PhysReg = VRM->getPhys(VirtReg);
assert(PhysReg != VirtRegMap::NO_PHYS_REG &&
"Instruction uses unmapped VirtReg");
assert(!MRI->isReserved(PhysReg) && "Reserved register assignment");
// Preserve semantics of sub-register operands.
unsigned SubReg = MO.getSubReg();
if (SubReg != 0) {
if (NoSubRegLiveness) {
// A virtual register kill refers to the whole register, so we may
// have to add <imp-use,kill> operands for the super-register. A
// partial redef always kills and redefines the super-register.
if (MO.readsReg() && (MO.isDef() || MO.isKill()))
SuperKills.push_back(PhysReg);
if (MO.isDef()) {
// Also add implicit defs for the super-register.
if (MO.isDead())
SuperDeads.push_back(PhysReg);
else
SuperDefs.push_back(PhysReg);
}
} else {
if (MO.isUse()) {
if (readsUndefSubreg(MO))
// We need to add an <undef> flag if the subregister is
// completely undefined (and we are not adding super-register
// defs).
MO.setIsUndef(true);
} else if (!MO.isDead()) {
assert(MO.isDef());
}
}
// The <def,undef> flag only makes sense for sub-register defs, and
// we are substituting a full physreg. An <imp-use,kill> operand
// from the SuperKills list will represent the partial read of the
// super-register.
if (MO.isDef())
MO.setIsUndef(false);
// PhysReg operands cannot have subregister indexes.
PhysReg = TRI->getSubReg(PhysReg, SubReg);
assert(PhysReg && "Invalid SubReg for physical register");
MO.setSubReg(0);
}
// Rewrite. Note we could have used MachineOperand::substPhysReg(), but
// we need the inlining here.
MO.setReg(PhysReg);
}
// Add any missing super-register kills after rewriting the whole
// instruction.
while (!SuperKills.empty())
MI->addRegisterKilled(SuperKills.pop_back_val(), TRI, true);
while (!SuperDeads.empty())
MI->addRegisterDead(SuperDeads.pop_back_val(), TRI, true);
while (!SuperDefs.empty())
MI->addRegisterDefined(SuperDefs.pop_back_val(), TRI);
DEBUG(dbgs() << "> " << *MI);
// Finally, remove any identity copies.
if (MI->isIdentityCopy()) {
++NumIdCopies;
DEBUG(dbgs() << "Deleting identity copy.\n");
if (Indexes)
Indexes->removeMachineInstrFromMaps(*MI);
// It's safe to erase MI because MII has already been incremented.
MI->eraseFromParent();
}
}
}
}
void VirtRegRewriter::rewrite() {
SmallVector<unsigned, 8> SuperDeads;
SmallVector<unsigned, 8> SuperDefs;
SmallVector<unsigned, 8> SuperKills;
SmallPtrSet<const MachineInstr *, 4> NoReturnInsts;
// Here we have a SparseSet to hold which PhysRegs are actually encountered
// in the MF we are about to iterate over so that later when we call
// setPhysRegUsed, we are only doing it for physRegs that were actually found
// in the program and not for all of the possible physRegs for the given
// target architecture. If the target has a lot of physRegs, then for a small
// program there will be a significant compile time reduction here.
PhysRegs.clear();
PhysRegs.setUniverse(TRI->getNumRegs());
// The function with uwtable should guarantee that the stack unwinder
// can unwind the stack to the previous frame. Thus, we can't apply the
// noreturn optimization if the caller function has uwtable attribute.
bool HasUWTable = MF->getFunction()->hasFnAttribute(Attribute::UWTable);
for (MachineFunction::iterator MBBI = MF->begin(), MBBE = MF->end();
MBBI != MBBE; ++MBBI) {
DEBUG(MBBI->print(dbgs(), Indexes));
bool IsExitBB = MBBI->succ_empty();
for (MachineBasicBlock::instr_iterator
MII = MBBI->instr_begin(), MIE = MBBI->instr_end(); MII != MIE;) {
MachineInstr *MI = MII;
++MII;
// Check if this instruction is a call to a noreturn function. If this
// is a call to noreturn function and we don't need the stack unwinding
// functionality (i.e. this function does not have uwtable attribute and
// the callee function has the nounwind attribute), then we can ignore
// the definitions set by this instruction.
if (!HasUWTable && IsExitBB && MI->isCall()) {
for (MachineInstr::mop_iterator MOI = MI->operands_begin(),
MOE = MI->operands_end(); MOI != MOE; ++MOI) {
MachineOperand &MO = *MOI;
if (!MO.isGlobal())
continue;
const Function *Func = dyn_cast<Function>(MO.getGlobal());
if (!Func || !Func->hasFnAttribute(Attribute::NoReturn) ||
// We need to keep correct unwind information
// even if the function will not return, since the
// runtime may need it.
!Func->hasFnAttribute(Attribute::NoUnwind))
continue;
NoReturnInsts.insert(MI);
break;
}
}
for (MachineInstr::mop_iterator MOI = MI->operands_begin(),
MOE = MI->operands_end(); MOI != MOE; ++MOI) {
MachineOperand &MO = *MOI;
// Make sure MRI knows about registers clobbered by regmasks.
if (MO.isRegMask())
MRI->addPhysRegsUsedFromRegMask(MO.getRegMask());
// If we encounter a VirtReg or PhysReg then get at the PhysReg and add
// it to the physreg bitset. Later we use only the PhysRegs that were
// actually encountered in the MF to populate the MRI's used physregs.
if (MO.isReg() && MO.getReg())
PhysRegs.insert(
TargetRegisterInfo::isVirtualRegister(MO.getReg()) ?
VRM->getPhys(MO.getReg()) :
MO.getReg());
if (!MO.isReg() || !TargetRegisterInfo::isVirtualRegister(MO.getReg()))
continue;
unsigned VirtReg = MO.getReg();
unsigned PhysReg = VRM->getPhys(VirtReg);
assert(PhysReg != VirtRegMap::NO_PHYS_REG &&
"Instruction uses unmapped VirtReg");
assert(!MRI->isReserved(PhysReg) && "Reserved register assignment");
// Preserve semantics of sub-register operands.
if (MO.getSubReg()) {
// A virtual register kill refers to the whole register, so we may
// have to add <imp-use,kill> operands for the super-register. A
// partial redef always kills and redefines the super-register.
if (MO.readsReg() && (MO.isDef() || MO.isKill()))
SuperKills.push_back(PhysReg);
if (MO.isDef()) {
// The <def,undef> flag only makes sense for sub-register defs, and
// we are substituting a full physreg. An <imp-use,kill> operand
// from the SuperKills list will represent the partial read of the
// super-register.
MO.setIsUndef(false);
// Also add implicit defs for the super-register.
if (MO.isDead())
SuperDeads.push_back(PhysReg);
else
SuperDefs.push_back(PhysReg);
}
// PhysReg operands cannot have subregister indexes.
PhysReg = TRI->getSubReg(PhysReg, MO.getSubReg());
assert(PhysReg && "Invalid SubReg for physical register");
MO.setSubReg(0);
}
// Rewrite. Note we could have used MachineOperand::substPhysReg(), but
// we need the inlining here.
MO.setReg(PhysReg);
}
// Add any missing super-register kills after rewriting the whole
// instruction.
while (!SuperKills.empty())
MI->addRegisterKilled(SuperKills.pop_back_val(), TRI, true);
while (!SuperDeads.empty())
MI->addRegisterDead(SuperDeads.pop_back_val(), TRI, true);
while (!SuperDefs.empty())
MI->addRegisterDefined(SuperDefs.pop_back_val(), TRI);
DEBUG(dbgs() << "> " << *MI);
// Finally, remove any identity copies.
if (MI->isIdentityCopy()) {
++NumIdCopies;
if (MI->getNumOperands() == 2) {
DEBUG(dbgs() << "Deleting identity copy.\n");
if (Indexes)
Indexes->removeMachineInstrFromMaps(MI);
// It's safe to erase MI because MII has already been incremented.
MI->eraseFromParent();
} else {
// Transform identity copy to a KILL to deal with subregisters.
MI->setDesc(TII->get(TargetOpcode::KILL));
DEBUG(dbgs() << "Identity copy: " << *MI);
}
}
}
}
// Tell MRI about physical registers in use.
if (NoReturnInsts.empty()) {
for (SparseSet<unsigned>::iterator
RegI = PhysRegs.begin(), E = PhysRegs.end(); RegI != E; ++RegI)
if (!MRI->reg_nodbg_empty(*RegI))
MRI->setPhysRegUsed(*RegI);
} else {
for (SparseSet<unsigned>::iterator
I = PhysRegs.begin(), E = PhysRegs.end(); I != E; ++I) {
unsigned Reg = *I;
if (MRI->reg_nodbg_empty(Reg))
continue;
// Check if this register has a use that will impact the rest of the
// code. Uses in debug and noreturn instructions do not impact the
// generated code.
for (MachineInstr &It : MRI->reg_nodbg_instructions(Reg)) {
if (!NoReturnInsts.count(&It)) {
MRI->setPhysRegUsed(Reg);
break;
}
}
}
}
}
bool LiveVariables::HandlePhysRegKill(unsigned Reg, MachineInstr *MI) {
MachineInstr *LastDef = PhysRegDef[Reg];
MachineInstr *LastUse = PhysRegUse[Reg];
if (!LastDef && !LastUse)
return false;
MachineInstr *LastRefOrPartRef = LastUse ? LastUse : LastDef;
unsigned LastRefOrPartRefDist = DistanceMap[LastRefOrPartRef];
// The whole register is used.
// AL =
// AH =
//
// = AX
// = AL, AX<imp-use, kill>
// AX =
//
// Or whole register is defined, but not used at all.
// AX<dead> =
// ...
// AX =
//
// Or whole register is defined, but only partly used.
// AX<dead> = AL<imp-def>
// = AL<kill>
// AX =
MachineInstr *LastPartDef = nullptr;
unsigned LastPartDefDist = 0;
SmallSet<unsigned, 8> PartUses;
for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs) {
unsigned SubReg = *SubRegs;
MachineInstr *Def = PhysRegDef[SubReg];
if (Def && Def != LastDef) {
// There was a def of this sub-register in between. This is a partial
// def, keep track of the last one.
unsigned Dist = DistanceMap[Def];
if (Dist > LastPartDefDist) {
LastPartDefDist = Dist;
LastPartDef = Def;
}
continue;
}
if (MachineInstr *Use = PhysRegUse[SubReg]) {
for (MCSubRegIterator SS(SubReg, TRI, /*IncludeSelf=*/true); SS.isValid();
++SS)
PartUses.insert(*SS);
unsigned Dist = DistanceMap[Use];
if (Dist > LastRefOrPartRefDist) {
LastRefOrPartRefDist = Dist;
LastRefOrPartRef = Use;
}
}
}
if (!PhysRegUse[Reg]) {
// Partial uses. Mark register def dead and add implicit def of
// sub-registers which are used.
// EAX<dead> = op AL<imp-def>
// That is, EAX def is dead but AL def extends pass it.
PhysRegDef[Reg]->addRegisterDead(Reg, TRI, true);
for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs) {
unsigned SubReg = *SubRegs;
if (!PartUses.count(SubReg))
continue;
bool NeedDef = true;
if (PhysRegDef[Reg] == PhysRegDef[SubReg]) {
MachineOperand *MO = PhysRegDef[Reg]->findRegisterDefOperand(SubReg);
if (MO) {
NeedDef = false;
assert(!MO->isDead());
}
}
if (NeedDef)
PhysRegDef[Reg]->addOperand(MachineOperand::CreateReg(SubReg,
true/*IsDef*/, true/*IsImp*/));
MachineInstr *LastSubRef = FindLastRefOrPartRef(SubReg);
if (LastSubRef)
LastSubRef->addRegisterKilled(SubReg, TRI, true);
else {
LastRefOrPartRef->addRegisterKilled(SubReg, TRI, true);
for (MCSubRegIterator SS(SubReg, TRI, /*IncludeSelf=*/true);
SS.isValid(); ++SS)
PhysRegUse[*SS] = LastRefOrPartRef;
}
for (MCSubRegIterator SS(SubReg, TRI); SS.isValid(); ++SS)
PartUses.erase(*SS);
}
} else if (LastRefOrPartRef == PhysRegDef[Reg] && LastRefOrPartRef != MI) {
if (LastPartDef)
// The last partial def kills the register.
LastPartDef->addOperand(MachineOperand::CreateReg(Reg, false/*IsDef*/,
true/*IsImp*/, true/*IsKill*/));
else {
MachineOperand *MO =
LastRefOrPartRef->findRegisterDefOperand(Reg, false, TRI);
bool NeedEC = MO->isEarlyClobber() && MO->getReg() != Reg;
// If the last reference is the last def, then it's not used at all.
// That is, unless we are currently processing the last reference itself.
LastRefOrPartRef->addRegisterDead(Reg, TRI, true);
if (NeedEC) {
// If we are adding a subreg def and the superreg def is marked early
// clobber, add an early clobber marker to the subreg def.
MO = LastRefOrPartRef->findRegisterDefOperand(Reg);
if (MO)
MO->setIsEarlyClobber();
}
}
} else
LastRefOrPartRef->addRegisterKilled(Reg, TRI, true);
return true;
}
/// shrinkToUses - After removing some uses of a register, shrink its live
/// range to just the remaining uses. This method does not compute reaching
/// defs for new uses, and it doesn't remove dead defs.
bool LiveIntervals::shrinkToUses(LiveInterval *li,
SmallVectorImpl<MachineInstr*> *dead) {
DEBUG(dbgs() << "Shrink: " << *li << '\n');
assert(TargetRegisterInfo::isVirtualRegister(li->reg)
&& "Can only shrink virtual registers");
// Find all the values used, including PHI kills.
SmallVector<std::pair<SlotIndex, VNInfo*>, 16> WorkList;
// Blocks that have already been added to WorkList as live-out.
SmallPtrSet<MachineBasicBlock*, 16> LiveOut;
// Visit all instructions reading li->reg.
for (MachineRegisterInfo::reg_iterator I = MRI->reg_begin(li->reg);
MachineInstr *UseMI = I.skipInstruction();) {
if (UseMI->isDebugValue() || !UseMI->readsVirtualRegister(li->reg))
continue;
SlotIndex Idx = getInstructionIndex(UseMI).getRegSlot();
LiveRangeQuery LRQ(*li, Idx);
VNInfo *VNI = LRQ.valueIn();
if (!VNI) {
// This shouldn't happen: readsVirtualRegister returns true, but there is
// no live value. It is likely caused by a target getting <undef> flags
// wrong.
DEBUG(dbgs() << Idx << '\t' << *UseMI
<< "Warning: Instr claims to read non-existent value in "
<< *li << '\n');
continue;
}
// Special case: An early-clobber tied operand reads and writes the
// register one slot early.
if (VNInfo *DefVNI = LRQ.valueDefined())
Idx = DefVNI->def;
WorkList.push_back(std::make_pair(Idx, VNI));
}
// Create a new live interval with only minimal live segments per def.
LiveInterval NewLI(li->reg, 0);
for (LiveInterval::vni_iterator I = li->vni_begin(), E = li->vni_end();
I != E; ++I) {
VNInfo *VNI = *I;
if (VNI->isUnused())
continue;
NewLI.addRange(LiveRange(VNI->def, VNI->def.getDeadSlot(), VNI));
}
// Keep track of the PHIs that are in use.
SmallPtrSet<VNInfo*, 8> UsedPHIs;
// Extend intervals to reach all uses in WorkList.
while (!WorkList.empty()) {
SlotIndex Idx = WorkList.back().first;
VNInfo *VNI = WorkList.back().second;
WorkList.pop_back();
const MachineBasicBlock *MBB = getMBBFromIndex(Idx.getPrevSlot());
SlotIndex BlockStart = getMBBStartIdx(MBB);
// Extend the live range for VNI to be live at Idx.
if (VNInfo *ExtVNI = NewLI.extendInBlock(BlockStart, Idx)) {
(void)ExtVNI;
assert(ExtVNI == VNI && "Unexpected existing value number");
// Is this a PHIDef we haven't seen before?
if (!VNI->isPHIDef() || VNI->def != BlockStart || !UsedPHIs.insert(VNI))
continue;
// The PHI is live, make sure the predecessors are live-out.
for (MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(),
PE = MBB->pred_end(); PI != PE; ++PI) {
if (!LiveOut.insert(*PI))
continue;
SlotIndex Stop = getMBBEndIdx(*PI);
// A predecessor is not required to have a live-out value for a PHI.
if (VNInfo *PVNI = li->getVNInfoBefore(Stop))
WorkList.push_back(std::make_pair(Stop, PVNI));
}
continue;
}
// VNI is live-in to MBB.
DEBUG(dbgs() << " live-in at " << BlockStart << '\n');
NewLI.addRange(LiveRange(BlockStart, Idx, VNI));
// Make sure VNI is live-out from the predecessors.
for (MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(),
PE = MBB->pred_end(); PI != PE; ++PI) {
if (!LiveOut.insert(*PI))
continue;
SlotIndex Stop = getMBBEndIdx(*PI);
assert(li->getVNInfoBefore(Stop) == VNI &&
"Wrong value out of predecessor");
WorkList.push_back(std::make_pair(Stop, VNI));
}
}
// Handle dead values.
bool CanSeparate = false;
for (LiveInterval::vni_iterator I = li->vni_begin(), E = li->vni_end();
I != E; ++I) {
VNInfo *VNI = *I;
if (VNI->isUnused())
continue;
LiveInterval::iterator LII = NewLI.FindLiveRangeContaining(VNI->def);
assert(LII != NewLI.end() && "Missing live range for PHI");
if (LII->end != VNI->def.getDeadSlot())
continue;
if (VNI->isPHIDef()) {
// This is a dead PHI. Remove it.
VNI->markUnused();
NewLI.removeRange(*LII);
DEBUG(dbgs() << "Dead PHI at " << VNI->def << " may separate interval\n");
CanSeparate = true;
} else {
// This is a dead def. Make sure the instruction knows.
MachineInstr *MI = getInstructionFromIndex(VNI->def);
assert(MI && "No instruction defining live value");
MI->addRegisterDead(li->reg, TRI);
if (dead && MI->allDefsAreDead()) {
DEBUG(dbgs() << "All defs dead: " << VNI->def << '\t' << *MI);
dead->push_back(MI);
}
}
}
// Move the trimmed ranges back.
li->ranges.swap(NewLI.ranges);
DEBUG(dbgs() << "Shrunk: " << *li << '\n');
return CanSeparate;
}
bool LiveVariables::HandlePhysRegKill(unsigned Reg, MachineInstr *MI) {
if (!PhysRegUse[Reg] && !PhysRegDef[Reg])
return false;
MachineInstr *LastRefOrPartRef = PhysRegUse[Reg]
? PhysRegUse[Reg] : PhysRegDef[Reg];
unsigned LastRefOrPartRefDist = DistanceMap[LastRefOrPartRef];
// The whole register is used.
// AL =
// AH =
//
// = AX
// = AL, AX<imp-use, kill>
// AX =
//
// Or whole register is defined, but not used at all.
// AX<dead> =
// ...
// AX =
//
// Or whole register is defined, but only partly used.
// AX<dead> = AL<imp-def>
// = AL<kill>
// AX =
SmallSet<unsigned, 8> PartUses;
for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
unsigned SubReg = *SubRegs; ++SubRegs) {
if (MachineInstr *Use = PhysRegUse[SubReg]) {
PartUses.insert(SubReg);
for (const unsigned *SS = TRI->getSubRegisters(SubReg); *SS; ++SS)
PartUses.insert(*SS);
unsigned Dist = DistanceMap[Use];
if (Dist > LastRefOrPartRefDist) {
LastRefOrPartRefDist = Dist;
LastRefOrPartRef = Use;
}
}
}
if (LastRefOrPartRef == PhysRegDef[Reg] && LastRefOrPartRef != MI)
// If the last reference is the last def, then it's not used at all.
// That is, unless we are currently processing the last reference itself.
LastRefOrPartRef->addRegisterDead(Reg, TRI, true);
/* Partial uses. Mark register def dead and add implicit def of
sub-registers which are used.
FIXME: LiveIntervalAnalysis can't handle this yet!
EAX<dead> = op AL<imp-def>
That is, EAX def is dead but AL def extends pass it.
Enable this after live interval analysis is fixed to improve codegen!
else if (!PhysRegUse[Reg]) {
PhysRegDef[Reg]->addRegisterDead(Reg, TRI, true);
for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
unsigned SubReg = *SubRegs; ++SubRegs) {
if (PartUses.count(SubReg)) {
PhysRegDef[Reg]->addOperand(MachineOperand::CreateReg(SubReg,
true, true));
LastRefOrPartRef->addRegisterKilled(SubReg, TRI, true);
for (const unsigned *SS = TRI->getSubRegisters(SubReg); *SS; ++SS)
PartUses.erase(*SS);
}
}
} */
else
LastRefOrPartRef->addRegisterKilled(Reg, TRI, true);
return true;
}
/// EmitMachineNode - Generate machine code for a target-specific node and
/// needed dependencies.
///
void InstrEmitter::
EmitMachineNode(SDNode *Node, bool IsClone, bool IsCloned,
DenseMap<SDValue, unsigned> &VRBaseMap) {
unsigned Opc = Node->getMachineOpcode();
// Handle subreg insert/extract specially
if (Opc == TargetOpcode::EXTRACT_SUBREG ||
Opc == TargetOpcode::INSERT_SUBREG ||
Opc == TargetOpcode::SUBREG_TO_REG) {
EmitSubregNode(Node, VRBaseMap, IsClone, IsCloned);
return;
}
// Handle COPY_TO_REGCLASS specially.
if (Opc == TargetOpcode::COPY_TO_REGCLASS) {
EmitCopyToRegClassNode(Node, VRBaseMap);
return;
}
// Handle REG_SEQUENCE specially.
if (Opc == TargetOpcode::REG_SEQUENCE) {
EmitRegSequence(Node, VRBaseMap, IsClone, IsCloned);
return;
}
if (Opc == TargetOpcode::IMPLICIT_DEF)
// We want a unique VR for each IMPLICIT_DEF use.
return;
const TargetInstrDesc &II = TII->get(Opc);
unsigned NumResults = CountResults(Node);
unsigned NodeOperands = CountOperands(Node);
bool HasPhysRegOuts = NumResults > II.getNumDefs() && II.getImplicitDefs()!=0;
#ifndef NDEBUG
unsigned NumMIOperands = NodeOperands + NumResults;
if (II.isVariadic())
assert(NumMIOperands >= II.getNumOperands() &&
"Too few operands for a variadic node!");
else
assert(NumMIOperands >= II.getNumOperands() &&
NumMIOperands <= II.getNumOperands()+II.getNumImplicitDefs() &&
"#operands for dag node doesn't match .td file!");
#endif
// Create the new machine instruction.
MachineInstr *MI = BuildMI(*MF, Node->getDebugLoc(), II);
// The MachineInstr constructor adds implicit-def operands. Scan through
// these to determine which are dead.
if (MI->getNumOperands() != 0 &&
Node->getValueType(Node->getNumValues()-1) == MVT::Glue) {
// First, collect all used registers.
SmallVector<unsigned, 8> UsedRegs;
for (SDNode *F = Node->getGluedUser(); F; F = F->getGluedUser())
if (F->getOpcode() == ISD::CopyFromReg)
UsedRegs.push_back(cast<RegisterSDNode>(F->getOperand(1))->getReg());
else {
// Collect declared implicit uses.
const TargetInstrDesc &TID = TII->get(F->getMachineOpcode());
UsedRegs.append(TID.getImplicitUses(),
TID.getImplicitUses() + TID.getNumImplicitUses());
// In addition to declared implicit uses, we must also check for
// direct RegisterSDNode operands.
for (unsigned i = 0, e = F->getNumOperands(); i != e; ++i)
if (RegisterSDNode *R = dyn_cast<RegisterSDNode>(F->getOperand(i))) {
unsigned Reg = R->getReg();
if (TargetRegisterInfo::isPhysicalRegister(Reg))
UsedRegs.push_back(Reg);
}
}
// Then mark unused registers as dead.
MI->setPhysRegsDeadExcept(UsedRegs, *TRI);
}
// Add result register values for things that are defined by this
// instruction.
if (NumResults)
CreateVirtualRegisters(Node, MI, II, IsClone, IsCloned, VRBaseMap);
// Emit all of the actual operands of this instruction, adding them to the
// instruction as appropriate.
bool HasOptPRefs = II.getNumDefs() > NumResults;
assert((!HasOptPRefs || !HasPhysRegOuts) &&
"Unable to cope with optional defs and phys regs defs!");
unsigned NumSkip = HasOptPRefs ? II.getNumDefs() - NumResults : 0;
for (unsigned i = NumSkip; i != NodeOperands; ++i)
AddOperand(MI, Node->getOperand(i), i-NumSkip+II.getNumDefs(), &II,
VRBaseMap, /*IsDebug=*/false, IsClone, IsCloned);
// Transfer all of the memory reference descriptions of this instruction.
MI->setMemRefs(cast<MachineSDNode>(Node)->memoperands_begin(),
cast<MachineSDNode>(Node)->memoperands_end());
// Insert the instruction into position in the block. This needs to
// happen before any custom inserter hook is called so that the
// hook knows where in the block to insert the replacement code.
MBB->insert(InsertPos, MI);
// Additional results must be physical register defs.
if (HasPhysRegOuts) {
for (unsigned i = II.getNumDefs(); i < NumResults; ++i) {
unsigned Reg = II.getImplicitDefs()[i - II.getNumDefs()];
if (Node->hasAnyUseOfValue(i))
EmitCopyFromReg(Node, i, IsClone, IsCloned, Reg, VRBaseMap);
// If there are no uses, mark the register as dead now, so that
// MachineLICM/Sink can see that it's dead. Don't do this if the
// node has a Glue value, for the benefit of targets still using
// Glue for values in physregs.
else if (Node->getValueType(Node->getNumValues()-1) != MVT::Glue)
MI->addRegisterDead(Reg, TRI);
}
}
// If the instruction has implicit defs and the node doesn't, mark the
// implicit def as dead. If the node has any glue outputs, we don't do this
// because we don't know what implicit defs are being used by glued nodes.
if (Node->getValueType(Node->getNumValues()-1) != MVT::Glue)
if (const unsigned *IDList = II.getImplicitDefs()) {
for (unsigned i = NumResults, e = II.getNumDefs()+II.getNumImplicitDefs();
i != e; ++i)
MI->addRegisterDead(IDList[i-II.getNumDefs()], TRI);
}
}
void VirtRegMap::rewrite(SlotIndexes *Indexes) {
DEBUG(dbgs() << "********** REWRITE VIRTUAL REGISTERS **********\n"
<< "********** Function: "
<< MF->getFunction()->getName() << '\n');
DEBUG(dump());
SmallVector<unsigned, 8> SuperDeads;
SmallVector<unsigned, 8> SuperDefs;
SmallVector<unsigned, 8> SuperKills;
for (MachineFunction::iterator MBBI = MF->begin(), MBBE = MF->end();
MBBI != MBBE; ++MBBI) {
DEBUG(MBBI->print(dbgs(), Indexes));
for (MachineBasicBlock::iterator MII = MBBI->begin(), MIE = MBBI->end();
MII != MIE;) {
MachineInstr *MI = MII;
++MII;
for (MachineInstr::mop_iterator MOI = MI->operands_begin(),
MOE = MI->operands_end(); MOI != MOE; ++MOI) {
MachineOperand &MO = *MOI;
if (!MO.isReg() || !TargetRegisterInfo::isVirtualRegister(MO.getReg()))
continue;
unsigned VirtReg = MO.getReg();
unsigned PhysReg = getPhys(VirtReg);
assert(PhysReg != NO_PHYS_REG && "Instruction uses unmapped VirtReg");
// Preserve semantics of sub-register operands.
if (MO.getSubReg()) {
// A virtual register kill refers to the whole register, so we may
// have to add <imp-use,kill> operands for the super-register. A
// partial redef always kills and redefines the super-register.
if (MO.readsReg() && (MO.isDef() || MO.isKill()))
SuperKills.push_back(PhysReg);
if (MO.isDef()) {
// The <def,undef> flag only makes sense for sub-register defs, and
// we are substituting a full physreg. An <imp-use,kill> operand
// from the SuperKills list will represent the partial read of the
// super-register.
MO.setIsUndef(false);
// Also add implicit defs for the super-register.
if (MO.isDead())
SuperDeads.push_back(PhysReg);
else
SuperDefs.push_back(PhysReg);
}
// PhysReg operands cannot have subregister indexes.
PhysReg = TRI->getSubReg(PhysReg, MO.getSubReg());
assert(PhysReg && "Invalid SubReg for physical register");
MO.setSubReg(0);
}
// Rewrite. Note we could have used MachineOperand::substPhysReg(), but
// we need the inlining here.
MO.setReg(PhysReg);
}
// Add any missing super-register kills after rewriting the whole
// instruction.
while (!SuperKills.empty())
MI->addRegisterKilled(SuperKills.pop_back_val(), TRI, true);
while (!SuperDeads.empty())
MI->addRegisterDead(SuperDeads.pop_back_val(), TRI, true);
while (!SuperDefs.empty())
MI->addRegisterDefined(SuperDefs.pop_back_val(), TRI);
DEBUG(dbgs() << "> " << *MI);
// Finally, remove any identity copies.
if (MI->isIdentityCopy()) {
++NumIdCopies;
if (MI->getNumOperands() == 2) {
DEBUG(dbgs() << "Deleting identity copy.\n");
RemoveMachineInstrFromMaps(MI);
if (Indexes)
Indexes->removeMachineInstrFromMaps(MI);
// It's safe to erase MI because MII has already been incremented.
MI->eraseFromParent();
} else {
// Transform identity copy to a KILL to deal with subregisters.
MI->setDesc(TII->get(TargetOpcode::KILL));
DEBUG(dbgs() << "Identity copy: " << *MI);
}
}
}
}
// Tell MRI about physical registers in use.
for (unsigned Reg = 1, RegE = TRI->getNumRegs(); Reg != RegE; ++Reg)
if (!MRI->reg_nodbg_empty(Reg))
MRI->setPhysRegUsed(Reg);
}
/// EmitNode - Generate machine code for a node and needed dependencies.
///
void InstrEmitter::EmitNode(SDNode *Node, bool IsClone, bool IsCloned,
DenseMap<SDValue, unsigned> &VRBaseMap,
DenseMap<MachineBasicBlock*, MachineBasicBlock*> *EM) {
// If machine instruction
if (Node->isMachineOpcode()) {
unsigned Opc = Node->getMachineOpcode();
// Handle subreg insert/extract specially
if (Opc == TargetOpcode::EXTRACT_SUBREG ||
Opc == TargetOpcode::INSERT_SUBREG ||
Opc == TargetOpcode::SUBREG_TO_REG) {
EmitSubregNode(Node, VRBaseMap);
return;
}
// Handle COPY_TO_REGCLASS specially.
if (Opc == TargetOpcode::COPY_TO_REGCLASS) {
EmitCopyToRegClassNode(Node, VRBaseMap);
return;
}
if (Opc == TargetOpcode::IMPLICIT_DEF)
// We want a unique VR for each IMPLICIT_DEF use.
return;
const TargetInstrDesc &II = TII->get(Opc);
unsigned NumResults = CountResults(Node);
unsigned NodeOperands = CountOperands(Node);
bool HasPhysRegOuts = (NumResults > II.getNumDefs()) &&
II.getImplicitDefs() != 0;
#ifndef NDEBUG
unsigned NumMIOperands = NodeOperands + NumResults;
assert((II.getNumOperands() == NumMIOperands ||
HasPhysRegOuts || II.isVariadic()) &&
"#operands for dag node doesn't match .td file!");
#endif
// Create the new machine instruction.
MachineInstr *MI = BuildMI(*MF, Node->getDebugLoc(), II);
// Add result register values for things that are defined by this
// instruction.
if (NumResults)
CreateVirtualRegisters(Node, MI, II, IsClone, IsCloned, VRBaseMap);
// Emit all of the actual operands of this instruction, adding them to the
// instruction as appropriate.
bool HasOptPRefs = II.getNumDefs() > NumResults;
assert((!HasOptPRefs || !HasPhysRegOuts) &&
"Unable to cope with optional defs and phys regs defs!");
unsigned NumSkip = HasOptPRefs ? II.getNumDefs() - NumResults : 0;
for (unsigned i = NumSkip; i != NodeOperands; ++i)
AddOperand(MI, Node->getOperand(i), i-NumSkip+II.getNumDefs(), &II,
VRBaseMap);
// Transfer all of the memory reference descriptions of this instruction.
MI->setMemRefs(cast<MachineSDNode>(Node)->memoperands_begin(),
cast<MachineSDNode>(Node)->memoperands_end());
if (II.usesCustomInsertionHook()) {
// Insert this instruction into the basic block using a target
// specific inserter which may returns a new basic block.
MBB = TLI->EmitInstrWithCustomInserter(MI, MBB, EM);
InsertPos = MBB->end();
} else {
MBB->insert(InsertPos, MI);
}
// Additional results must be an physical register def.
if (HasPhysRegOuts) {
for (unsigned i = II.getNumDefs(); i < NumResults; ++i) {
unsigned Reg = II.getImplicitDefs()[i - II.getNumDefs()];
if (Node->hasAnyUseOfValue(i))
EmitCopyFromReg(Node, i, IsClone, IsCloned, Reg, VRBaseMap);
// If there are no uses, mark the register as dead now, so that
// MachineLICM/Sink can see that it's dead. Don't do this if the
// node has a Flag value, for the benefit of targets still using
// Flag for values in physregs.
else if (Node->getValueType(Node->getNumValues()-1) != MVT::Flag)
MI->addRegisterDead(Reg, TRI);
}
}
return;
}
switch (Node->getOpcode()) {
default:
#ifndef NDEBUG
Node->dump();
#endif
llvm_unreachable("This target-independent node should have been selected!");
break;
case ISD::EntryToken:
llvm_unreachable("EntryToken should have been excluded from the schedule!");
break;
case ISD::MERGE_VALUES:
case ISD::TokenFactor: // fall thru
break;
case ISD::CopyToReg: {
unsigned SrcReg;
SDValue SrcVal = Node->getOperand(2);
if (RegisterSDNode *R = dyn_cast<RegisterSDNode>(SrcVal))
SrcReg = R->getReg();
else
SrcReg = getVR(SrcVal, VRBaseMap);
unsigned DestReg = cast<RegisterSDNode>(Node->getOperand(1))->getReg();
if (SrcReg == DestReg) // Coalesced away the copy? Ignore.
break;
const TargetRegisterClass *SrcTRC = 0, *DstTRC = 0;
// Get the register classes of the src/dst.
if (TargetRegisterInfo::isVirtualRegister(SrcReg))
SrcTRC = MRI->getRegClass(SrcReg);
else
SrcTRC = TRI->getPhysicalRegisterRegClass(SrcReg,SrcVal.getValueType());
if (TargetRegisterInfo::isVirtualRegister(DestReg))
DstTRC = MRI->getRegClass(DestReg);
else
DstTRC = TRI->getPhysicalRegisterRegClass(DestReg,
Node->getOperand(1).getValueType());
bool Emitted = TII->copyRegToReg(*MBB, InsertPos, DestReg, SrcReg,
DstTRC, SrcTRC);
assert(Emitted && "Unable to issue a copy instruction!\n");
(void) Emitted;
break;
}
case ISD::CopyFromReg: {
unsigned SrcReg = cast<RegisterSDNode>(Node->getOperand(1))->getReg();
EmitCopyFromReg(Node, 0, IsClone, IsCloned, SrcReg, VRBaseMap);
break;
}
case ISD::INLINEASM: {
unsigned NumOps = Node->getNumOperands();
if (Node->getOperand(NumOps-1).getValueType() == MVT::Flag)
--NumOps; // Ignore the flag operand.
// Create the inline asm machine instruction.
MachineInstr *MI = BuildMI(*MF, Node->getDebugLoc(),
TII->get(TargetOpcode::INLINEASM));
// Add the asm string as an external symbol operand.
const char *AsmStr =
cast<ExternalSymbolSDNode>(Node->getOperand(1))->getSymbol();
MI->addOperand(MachineOperand::CreateES(AsmStr));
// Add all of the operand registers to the instruction.
for (unsigned i = 2; i != NumOps;) {
unsigned Flags =
cast<ConstantSDNode>(Node->getOperand(i))->getZExtValue();
unsigned NumVals = InlineAsm::getNumOperandRegisters(Flags);
MI->addOperand(MachineOperand::CreateImm(Flags));
++i; // Skip the ID value.
switch (Flags & 7) {
default: llvm_unreachable("Bad flags!");
case 2: // Def of register.
for (; NumVals; --NumVals, ++i) {
unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
MI->addOperand(MachineOperand::CreateReg(Reg, true));
}
break;
case 6: // Def of earlyclobber register.
for (; NumVals; --NumVals, ++i) {
unsigned Reg = cast<RegisterSDNode>(Node->getOperand(i))->getReg();
MI->addOperand(MachineOperand::CreateReg(Reg, true, false, false,
false, false, true));
}
break;
case 1: // Use of register.
case 3: // Immediate.
case 4: // Addressing mode.
// The addressing mode has been selected, just add all of the
// operands to the machine instruction.
for (; NumVals; --NumVals, ++i)
AddOperand(MI, Node->getOperand(i), 0, 0, VRBaseMap);
break;
}
}
MBB->insert(InsertPos, MI);
break;
}
}
}
