/// HandlePhysRegUse - Turn previous partial def's into read/mod/writes. Add
/// implicit defs to a machine instruction if there was an earlier def of its
/// super-register.
void LiveVariables::HandlePhysRegUse(unsigned Reg, MachineInstr *MI) {
MachineInstr *LastDef = PhysRegDef[Reg];
// If there was a previous use or a "full" def all is well.
if (!LastDef && !PhysRegUse[Reg]) {
// Otherwise, the last sub-register def implicitly defines this register.
// e.g.
// AH =
// AL = ... <imp-def EAX>, <imp-kill AH>
// = AH
// ...
// = EAX
// All of the sub-registers must have been defined before the use of Reg!
SmallSet<unsigned, 4> PartDefRegs;
MachineInstr *LastPartialDef = FindLastPartialDef(Reg, PartDefRegs);
// If LastPartialDef is NULL, it must be using a livein register.
if (LastPartialDef) {
LastPartialDef->addOperand(MachineOperand::CreateReg(Reg, true/*IsDef*/,
true/*IsImp*/));
PhysRegDef[Reg] = LastPartialDef;
SmallSet<unsigned, 8> Processed;
for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
unsigned SubReg = *SubRegs; ++SubRegs) {
if (Processed.count(SubReg))
continue;
if (PartDefRegs.count(SubReg))
continue;
// This part of Reg was defined before the last partial def. It's killed
// here.
LastPartialDef->addOperand(MachineOperand::CreateReg(SubReg,
false/*IsDef*/,
true/*IsImp*/));
PhysRegDef[SubReg] = LastPartialDef;
for (const unsigned *SS = TRI->getSubRegisters(SubReg); *SS; ++SS)
Processed.insert(*SS);
}
}
}
else if (LastDef && !PhysRegUse[Reg] &&
!LastDef->findRegisterDefOperand(Reg))
// Last def defines the super register, add an implicit def of reg.
LastDef->addOperand(MachineOperand::CreateReg(Reg,
true/*IsDef*/, true/*IsImp*/));
// Remember this use.
PhysRegUse[Reg] = MI;
for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
unsigned SubReg = *SubRegs; ++SubRegs)
PhysRegUse[SubReg] = MI;
}
// Get the subreg type that is most likely to be coalesced
// for an SPR register that will be used in VDUP32d pseudo.
unsigned A15SDOptimizer::getPrefSPRLane(unsigned SReg) {
if (!TRI->isVirtualRegister(SReg))
return getDPRLaneFromSPR(SReg);
MachineInstr *MI = MRI->getVRegDef(SReg);
if (!MI) return ARM::ssub_0;
MachineOperand *MO = MI->findRegisterDefOperand(SReg);
assert(MO->isReg() && "Non-register operand found!");
if (!MO) return ARM::ssub_0;
if (MI->isCopy() && usesRegClass(MI->getOperand(1),
&ARM::SPRRegClass)) {
SReg = MI->getOperand(1).getReg();
}
if (TargetRegisterInfo::isVirtualRegister(SReg)) {
if (MO->getSubReg() == ARM::ssub_1) return ARM::ssub_1;
return ARM::ssub_0;
}
return getDPRLaneFromSPR(SReg);
}
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;
}
MachineBasicBlock * R600TargetLowering::EmitInstrWithCustomInserter(
MachineInstr * MI, MachineBasicBlock * BB) const
{
MachineFunction * MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
MachineBasicBlock::iterator I = *MI;
switch (MI->getOpcode()) {
default: return AMDGPUTargetLowering::EmitInstrWithCustomInserter(MI, BB);
case AMDGPU::TGID_X:
addLiveIn(MI, MF, MRI, TII, AMDGPU::T1_X);
break;
case AMDGPU::TGID_Y:
addLiveIn(MI, MF, MRI, TII, AMDGPU::T1_Y);
break;
case AMDGPU::TGID_Z:
addLiveIn(MI, MF, MRI, TII, AMDGPU::T1_Z);
break;
case AMDGPU::TIDIG_X:
addLiveIn(MI, MF, MRI, TII, AMDGPU::T0_X);
break;
case AMDGPU::TIDIG_Y:
addLiveIn(MI, MF, MRI, TII, AMDGPU::T0_Y);
break;
case AMDGPU::TIDIG_Z:
addLiveIn(MI, MF, MRI, TII, AMDGPU::T0_Z);
break;
case AMDGPU::NGROUPS_X:
lowerImplicitParameter(MI, *BB, MRI, 0);
break;
case AMDGPU::NGROUPS_Y:
lowerImplicitParameter(MI, *BB, MRI, 1);
break;
case AMDGPU::NGROUPS_Z:
lowerImplicitParameter(MI, *BB, MRI, 2);
break;
case AMDGPU::GLOBAL_SIZE_X:
lowerImplicitParameter(MI, *BB, MRI, 3);
break;
case AMDGPU::GLOBAL_SIZE_Y:
lowerImplicitParameter(MI, *BB, MRI, 4);
break;
case AMDGPU::GLOBAL_SIZE_Z:
lowerImplicitParameter(MI, *BB, MRI, 5);
break;
case AMDGPU::LOCAL_SIZE_X:
lowerImplicitParameter(MI, *BB, MRI, 6);
break;
case AMDGPU::LOCAL_SIZE_Y:
lowerImplicitParameter(MI, *BB, MRI, 7);
break;
case AMDGPU::LOCAL_SIZE_Z:
lowerImplicitParameter(MI, *BB, MRI, 8);
break;
case AMDGPU::CLAMP_R600:
MI->getOperand(0).addTargetFlag(MO_FLAG_CLAMP);
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::MOV))
.addOperand(MI->getOperand(0))
.addOperand(MI->getOperand(1));
break;
case AMDGPU::FABS_R600:
MI->getOperand(1).addTargetFlag(MO_FLAG_ABS);
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::MOV))
.addOperand(MI->getOperand(0))
.addOperand(MI->getOperand(1));
break;
case AMDGPU::FNEG_R600:
MI->getOperand(1).addTargetFlag(MO_FLAG_NEG);
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::MOV))
.addOperand(MI->getOperand(0))
.addOperand(MI->getOperand(1));
break;
case AMDGPU::R600_LOAD_CONST:
{
int64_t RegIndex = MI->getOperand(1).getImm();
unsigned ConstantReg = AMDGPU::R600_CReg32RegClass.getRegister(RegIndex);
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::COPY))
.addOperand(MI->getOperand(0))
.addReg(ConstantReg);
break;
}
case AMDGPU::LOAD_INPUT:
{
int64_t RegIndex = MI->getOperand(1).getImm();
addLiveIn(MI, MF, MRI, TII,
AMDGPU::R600_TReg32RegClass.getRegister(RegIndex));
break;
}
case AMDGPU::MASK_WRITE:
{
unsigned maskedRegister = MI->getOperand(0).getReg();
assert(TargetRegisterInfo::isVirtualRegister(maskedRegister));
MachineInstr * defInstr = MRI.getVRegDef(maskedRegister);
MachineOperand * def = defInstr->findRegisterDefOperand(maskedRegister);
def->addTargetFlag(MO_FLAG_MASK);
// Return early so the instruction is not erased
return BB;
}
case AMDGPU::RAT_WRITE_CACHELESS_eg:
{
// Convert to DWORD address
unsigned NewAddr = MRI.createVirtualRegister(
AMDGPU::R600_TReg32_XRegisterClass);
unsigned ShiftValue = MRI.createVirtualRegister(
AMDGPU::R600_TReg32RegisterClass);
// XXX In theory, we should be able to pass ShiftValue directly to
// the LSHR_eg instruction as an inline literal, but I tried doing it
// this way and it didn't produce the correct results.
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::MOV), ShiftValue)
.addReg(AMDGPU::ALU_LITERAL_X)
.addImm(2);
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::LSHR_eg), NewAddr)
.addOperand(MI->getOperand(1))
.addReg(ShiftValue);
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(MI->getOpcode()))
.addOperand(MI->getOperand(0))
.addReg(NewAddr);
break;
}
case AMDGPU::STORE_OUTPUT:
{
int64_t OutputIndex = MI->getOperand(1).getImm();
unsigned OutputReg = AMDGPU::R600_TReg32RegClass.getRegister(OutputIndex);
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::COPY), OutputReg)
.addOperand(MI->getOperand(0));
if (!MRI.isLiveOut(OutputReg)) {
MRI.addLiveOut(OutputReg);
}
break;
}
case AMDGPU::RESERVE_REG:
{
R600MachineFunctionInfo * MFI = MF->getInfo<R600MachineFunctionInfo>();
int64_t ReservedIndex = MI->getOperand(0).getImm();
unsigned ReservedReg =
AMDGPU::R600_TReg32RegClass.getRegister(ReservedIndex);
MFI->ReservedRegs.push_back(ReservedReg);
break;
}
case AMDGPU::TXD:
{
unsigned t0 = MRI.createVirtualRegister(AMDGPU::R600_Reg128RegisterClass);
unsigned t1 = MRI.createVirtualRegister(AMDGPU::R600_Reg128RegisterClass);
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::TEX_SET_GRADIENTS_H), t0)
.addOperand(MI->getOperand(3))
.addOperand(MI->getOperand(4))
.addOperand(MI->getOperand(5));
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::TEX_SET_GRADIENTS_V), t1)
.addOperand(MI->getOperand(2))
.addOperand(MI->getOperand(4))
.addOperand(MI->getOperand(5));
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::TEX_SAMPLE_G))
.addOperand(MI->getOperand(0))
.addOperand(MI->getOperand(1))
.addOperand(MI->getOperand(4))
.addOperand(MI->getOperand(5))
.addReg(t0, RegState::Implicit)
.addReg(t1, RegState::Implicit);
break;
}
case AMDGPU::TXD_SHADOW:
{
unsigned t0 = MRI.createVirtualRegister(AMDGPU::R600_Reg128RegisterClass);
unsigned t1 = MRI.createVirtualRegister(AMDGPU::R600_Reg128RegisterClass);
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::TEX_SET_GRADIENTS_H), t0)
.addOperand(MI->getOperand(3))
.addOperand(MI->getOperand(4))
.addOperand(MI->getOperand(5));
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::TEX_SET_GRADIENTS_V), t1)
.addOperand(MI->getOperand(2))
.addOperand(MI->getOperand(4))
.addOperand(MI->getOperand(5));
BuildMI(*BB, I, BB->findDebugLoc(I), TII->get(AMDGPU::TEX_SAMPLE_C_G))
.addOperand(MI->getOperand(0))
.addOperand(MI->getOperand(1))
.addOperand(MI->getOperand(4))
.addOperand(MI->getOperand(5))
.addReg(t0, RegState::Implicit)
.addReg(t1, RegState::Implicit);
break;
}
}
MI->eraseFromParent();
return BB;
}
bool Thumb2SizeReduce::ReduceMBB(MachineBasicBlock &MBB) {
bool Modified = false;
// Yes, CPSR could be livein.
bool LiveCPSR = MBB.isLiveIn(ARM::CPSR);
MachineInstr *BundleMI = 0;
CPSRDef = 0;
HighLatencyCPSR = false;
// Check predecessors for the latest CPSRDef.
for (MachineBasicBlock::pred_iterator
I = MBB.pred_begin(), E = MBB.pred_end(); I != E; ++I) {
const MBBInfo &PInfo = BlockInfo[(*I)->getNumber()];
if (!PInfo.Visited) {
// Since blocks are visited in RPO, this must be a back-edge.
continue;
}
if (PInfo.HighLatencyCPSR) {
HighLatencyCPSR = true;
break;
}
}
// If this BB loops back to itself, conservatively avoid narrowing the
// first instruction that does partial flag update.
bool IsSelfLoop = MBB.isSuccessor(&MBB);
MachineBasicBlock::instr_iterator MII = MBB.instr_begin(),E = MBB.instr_end();
MachineBasicBlock::instr_iterator NextMII;
for (; MII != E; MII = NextMII) {
NextMII = llvm::next(MII);
MachineInstr *MI = &*MII;
if (MI->isBundle()) {
BundleMI = MI;
continue;
}
if (MI->isDebugValue())
continue;
LiveCPSR = UpdateCPSRUse(*MI, LiveCPSR);
// Does NextMII belong to the same bundle as MI?
bool NextInSameBundle = NextMII != E && NextMII->isBundledWithPred();
if (ReduceMI(MBB, MI, LiveCPSR, IsSelfLoop)) {
Modified = true;
MachineBasicBlock::instr_iterator I = prior(NextMII);
MI = &*I;
// Removing and reinserting the first instruction in a bundle will break
// up the bundle. Fix the bundling if it was broken.
if (NextInSameBundle && !NextMII->isBundledWithPred())
NextMII->bundleWithPred();
}
if (!NextInSameBundle && MI->isInsideBundle()) {
// FIXME: Since post-ra scheduler operates on bundles, the CPSR kill
// marker is only on the BUNDLE instruction. Process the BUNDLE
// instruction as we finish with the bundled instruction to work around
// the inconsistency.
if (BundleMI->killsRegister(ARM::CPSR))
LiveCPSR = false;
MachineOperand *MO = BundleMI->findRegisterDefOperand(ARM::CPSR);
if (MO && !MO->isDead())
LiveCPSR = true;
}
bool DefCPSR = false;
LiveCPSR = UpdateCPSRDef(*MI, LiveCPSR, DefCPSR);
if (MI->isCall()) {
// Calls don't really set CPSR.
CPSRDef = 0;
HighLatencyCPSR = false;
IsSelfLoop = false;
} else if (DefCPSR) {
// This is the last CPSR defining instruction.
CPSRDef = MI;
HighLatencyCPSR = isHighLatencyCPSR(CPSRDef);
IsSelfLoop = false;
}
}
MBBInfo &Info = BlockInfo[MBB.getNumber()];
Info.HighLatencyCPSR = HighLatencyCPSR;
Info.Visited = true;
return Modified;
}
bool Thumb2SizeReduce::ReduceMBB(MachineBasicBlock &MBB) {
bool Modified = false;
// Yes, CPSR could be livein.
bool LiveCPSR = MBB.isLiveIn(ARM::CPSR);
MachineInstr *CPSRDef = 0;
MachineInstr *BundleMI = 0;
// If this BB loops back to itself, conservatively avoid narrowing the
// first instruction that does partial flag update.
bool IsSelfLoop = MBB.isSuccessor(&MBB);
MachineBasicBlock::instr_iterator MII = MBB.instr_begin(), E = MBB.instr_end();
MachineBasicBlock::instr_iterator NextMII;
for (; MII != E; MII = NextMII) {
NextMII = llvm::next(MII);
MachineInstr *MI = &*MII;
if (MI->isBundle()) {
BundleMI = MI;
continue;
}
LiveCPSR = UpdateCPSRUse(*MI, LiveCPSR);
unsigned Opcode = MI->getOpcode();
DenseMap<unsigned, unsigned>::iterator OPI = ReduceOpcodeMap.find(Opcode);
if (OPI != ReduceOpcodeMap.end()) {
const ReduceEntry &Entry = ReduceTable[OPI->second];
// Ignore "special" cases for now.
if (Entry.Special) {
if (ReduceSpecial(MBB, MI, Entry, LiveCPSR, CPSRDef, IsSelfLoop)) {
Modified = true;
MachineBasicBlock::instr_iterator I = prior(NextMII);
MI = &*I;
}
goto ProcessNext;
}
// Try to transform to a 16-bit two-address instruction.
if (Entry.NarrowOpc2 &&
ReduceTo2Addr(MBB, MI, Entry, LiveCPSR, CPSRDef, IsSelfLoop)) {
Modified = true;
MachineBasicBlock::instr_iterator I = prior(NextMII);
MI = &*I;
goto ProcessNext;
}
// Try to transform to a 16-bit non-two-address instruction.
if (Entry.NarrowOpc1 &&
ReduceToNarrow(MBB, MI, Entry, LiveCPSR, CPSRDef, IsSelfLoop)) {
Modified = true;
MachineBasicBlock::instr_iterator I = prior(NextMII);
MI = &*I;
}
}
ProcessNext:
if (NextMII != E && MI->isInsideBundle() && !NextMII->isInsideBundle()) {
// FIXME: Since post-ra scheduler operates on bundles, the CPSR kill
// marker is only on the BUNDLE instruction. Process the BUNDLE
// instruction as we finish with the bundled instruction to work around
// the inconsistency.
if (BundleMI->killsRegister(ARM::CPSR))
LiveCPSR = false;
MachineOperand *MO = BundleMI->findRegisterDefOperand(ARM::CPSR);
if (MO && !MO->isDead())
LiveCPSR = true;
}
bool DefCPSR = false;
LiveCPSR = UpdateCPSRDef(*MI, LiveCPSR, DefCPSR);
if (MI->isCall()) {
// Calls don't really set CPSR.
CPSRDef = 0;
IsSelfLoop = false;
} else if (DefCPSR) {
// This is the last CPSR defining instruction.
CPSRDef = MI;
IsSelfLoop = false;
}
}
return Modified;
}
