// the two operands returned by findCommutedOpIndices.
MachineInstr *TargetInstrInfoImpl::commuteInstruction(MachineInstr *MI,
bool NewMI) const {
- const TargetInstrDesc &TID = MI->getDesc();
- bool HasDef = TID.getNumDefs();
+ const MCInstrDesc &MCID = MI->getDesc();
+ bool HasDef = MCID.getNumDefs();
if (HasDef && !MI->getOperand(0).isReg())
// No idea how to commute this instruction. Target should implement its own.
return 0;
assert(MI->getOperand(Idx1).isReg() && MI->getOperand(Idx2).isReg() &&
"This only knows how to commute register operands so far");
+ unsigned Reg0 = HasDef ? MI->getOperand(0).getReg() : 0;
unsigned Reg1 = MI->getOperand(Idx1).getReg();
unsigned Reg2 = MI->getOperand(Idx2).getReg();
bool Reg1IsKill = MI->getOperand(Idx1).isKill();
bool Reg2IsKill = MI->getOperand(Idx2).isKill();
- bool ChangeReg0 = false;
- if (HasDef && MI->getOperand(0).getReg() == Reg1) {
- // Must be two address instruction!
- assert(MI->getDesc().getOperandConstraint(0, TOI::TIED_TO) &&
- "Expecting a two-address instruction!");
+ // If destination is tied to either of the commuted source register, then
+ // it must be updated.
+ if (HasDef && Reg0 == Reg1 &&
+ MI->getDesc().getOperandConstraint(Idx1, MCOI::TIED_TO) == 0) {
Reg2IsKill = false;
- ChangeReg0 = true;
+ Reg0 = Reg2;
+ } else if (HasDef && Reg0 == Reg2 &&
+ MI->getDesc().getOperandConstraint(Idx2, MCOI::TIED_TO) == 0) {
+ Reg1IsKill = false;
+ Reg0 = Reg1;
}
if (NewMI) {
// Create a new instruction.
- unsigned Reg0 = HasDef
- ? (ChangeReg0 ? Reg2 : MI->getOperand(0).getReg()) : 0;
bool Reg0IsDead = HasDef ? MI->getOperand(0).isDead() : false;
MachineFunction &MF = *MI->getParent()->getParent();
if (HasDef)
.addReg(Reg1, getKillRegState(Reg2IsKill));
}
- if (ChangeReg0)
- MI->getOperand(0).setReg(Reg2);
+ if (HasDef)
+ MI->getOperand(0).setReg(Reg0);
MI->getOperand(Idx2).setReg(Reg1);
MI->getOperand(Idx1).setReg(Reg2);
MI->getOperand(Idx2).setIsKill(Reg1IsKill);
bool TargetInstrInfoImpl::findCommutedOpIndices(MachineInstr *MI,
unsigned &SrcOpIdx1,
unsigned &SrcOpIdx2) const {
- const TargetInstrDesc &TID = MI->getDesc();
- if (!TID.isCommutable())
+ const MCInstrDesc &MCID = MI->getDesc();
+ if (!MCID.isCommutable())
return false;
// This assumes v0 = op v1, v2 and commuting would swap v1 and v2. If this
// is not true, then the target must implement this.
- SrcOpIdx1 = TID.getNumDefs();
+ SrcOpIdx1 = MCID.getNumDefs();
SrcOpIdx2 = SrcOpIdx1 + 1;
if (!MI->getOperand(SrcOpIdx1).isReg() ||
!MI->getOperand(SrcOpIdx2).isReg())
bool TargetInstrInfoImpl::PredicateInstruction(MachineInstr *MI,
const SmallVectorImpl<MachineOperand> &Pred) const {
bool MadeChange = false;
- const TargetInstrDesc &TID = MI->getDesc();
- if (!TID.isPredicable())
+ const MCInstrDesc &MCID = MI->getDesc();
+ if (!MCID.isPredicable())
return false;
for (unsigned j = 0, i = 0, e = MI->getNumOperands(); i != e; ++i) {
- if (TID.OpInfo[i].isPredicate()) {
+ if (MCID.OpInfo[i].isPredicate()) {
MachineOperand &MO = MI->getOperand(i);
if (MO.isReg()) {
MO.setReg(Pred[j].getReg());
return MadeChange;
}
+bool TargetInstrInfoImpl::hasLoadFromStackSlot(const MachineInstr *MI,
+ const MachineMemOperand *&MMO,
+ int &FrameIndex) const {
+ for (MachineInstr::mmo_iterator o = MI->memoperands_begin(),
+ oe = MI->memoperands_end();
+ o != oe;
+ ++o) {
+ if ((*o)->isLoad() && (*o)->getValue())
+ if (const FixedStackPseudoSourceValue *Value =
+ dyn_cast<const FixedStackPseudoSourceValue>((*o)->getValue())) {
+ FrameIndex = Value->getFrameIndex();
+ MMO = *o;
+ return true;
+ }
+ }
+ return false;
+}
+
+bool TargetInstrInfoImpl::hasStoreToStackSlot(const MachineInstr *MI,
+ const MachineMemOperand *&MMO,
+ int &FrameIndex) const {
+ for (MachineInstr::mmo_iterator o = MI->memoperands_begin(),
+ oe = MI->memoperands_end();
+ o != oe;
+ ++o) {
+ if ((*o)->isStore() && (*o)->getValue())
+ if (const FixedStackPseudoSourceValue *Value =
+ dyn_cast<const FixedStackPseudoSourceValue>((*o)->getValue())) {
+ FrameIndex = Value->getFrameIndex();
+ MMO = *o;
+ return true;
+ }
+ }
+ return false;
+}
+
void TargetInstrInfoImpl::reMaterialize(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned DestReg,
const TargetInstrInfo &TII = *TM.getInstrInfo();
const TargetRegisterInfo &TRI = *TM.getRegisterInfo();
+ // Remat clients assume operand 0 is the defined register.
+ if (!MI->getNumOperands() || !MI->getOperand(0).isReg())
+ return false;
+ unsigned DefReg = MI->getOperand(0).getReg();
+
+ // A sub-register definition can only be rematerialized if the instruction
+ // doesn't read the other parts of the register. Otherwise it is really a
+ // read-modify-write operation on the full virtual register which cannot be
+ // moved safely.
+ if (TargetRegisterInfo::isVirtualRegister(DefReg) &&
+ MI->getOperand(0).getSubReg() && MI->readsVirtualRegister(DefReg))
+ return false;
+
// A load from a fixed stack slot can be rematerialized. This may be
// redundant with subsequent checks, but it's target-independent,
// simple, and a common case.
MF.getFrameInfo()->isImmutableObjectIndex(FrameIdx))
return true;
- const TargetInstrDesc &TID = MI->getDesc();
+ const MCInstrDesc &MCID = MI->getDesc();
// Avoid instructions obviously unsafe for remat.
- if (TID.isNotDuplicable() || TID.mayStore() ||
+ if (MCID.isNotDuplicable() || MCID.mayStore() ||
MI->hasUnmodeledSideEffects())
return false;
return false;
// Avoid instructions which load from potentially varying memory.
- if (TID.mayLoad() && !MI->isInvariantLoad(AA))
+ if (MCID.mayLoad() && !MI->isInvariantLoad(AA))
return false;
// If any of the registers accessed are non-constant, conservatively assume
continue;
}
- // Only allow one virtual-register def, and that in the first operand.
- if (MO.isDef() != (i == 0))
+ // Only allow one virtual-register def. There may be multiple defs of the
+ // same virtual register, though.
+ if (MO.isDef() && Reg != DefReg)
return false;
// Don't allow any virtual-register uses. Rematting an instruction with