- // Try spliting an indexed load / store to a un-indexed one plus an add/sub
- // operation.
- unsigned MemOpc = getUnindexedOpcode(MI->getOpcode());
- if (MemOpc == 0)
- return NULL;
-
- MachineInstr *UpdateMI = NULL;
- MachineInstr *MemMI = NULL;
- unsigned AddrMode = (TSFlags & ARMII::AddrModeMask);
- const TargetInstrDesc &TID = MI->getDesc();
- unsigned NumOps = TID.getNumOperands();
- bool isLoad = !TID.mayStore();
- const MachineOperand &WB = isLoad ? MI->getOperand(1) : MI->getOperand(0);
- const MachineOperand &Base = MI->getOperand(2);
- const MachineOperand &Offset = MI->getOperand(NumOps-3);
- unsigned WBReg = WB.getReg();
- unsigned BaseReg = Base.getReg();
- unsigned OffReg = Offset.getReg();
- unsigned OffImm = MI->getOperand(NumOps-2).getImm();
- ARMCC::CondCodes Pred = (ARMCC::CondCodes)MI->getOperand(NumOps-1).getImm();
- switch (AddrMode) {
- default:
- assert(false && "Unknown indexed op!");
- return NULL;
- case ARMII::AddrMode2: {
- bool isSub = ARM_AM::getAM2Op(OffImm) == ARM_AM::sub;
- unsigned Amt = ARM_AM::getAM2Offset(OffImm);
- if (OffReg == 0) {
- int SOImmVal = ARM_AM::getSOImmVal(Amt);
- if (SOImmVal == -1)
- // Can't encode it in a so_imm operand. This transformation will
- // add more than 1 instruction. Abandon!
- return NULL;
- UpdateMI = BuildMI(MF, get(isSub ? ARM::SUBri : ARM::ADDri), WBReg)
- .addReg(BaseReg).addImm(SOImmVal)
- .addImm(Pred).addReg(0).addReg(0);
- } else if (Amt != 0) {
- ARM_AM::ShiftOpc ShOpc = ARM_AM::getAM2ShiftOpc(OffImm);
- unsigned SOOpc = ARM_AM::getSORegOpc(ShOpc, Amt);
- UpdateMI = BuildMI(MF, get(isSub ? ARM::SUBrs : ARM::ADDrs), WBReg)
- .addReg(BaseReg).addReg(OffReg).addReg(0).addImm(SOOpc)
- .addImm(Pred).addReg(0).addReg(0);
- } else
- UpdateMI = BuildMI(MF, get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg)
- .addReg(BaseReg).addReg(OffReg)
- .addImm(Pred).addReg(0).addReg(0);
- break;
- }
- case ARMII::AddrMode3 : {
- bool isSub = ARM_AM::getAM3Op(OffImm) == ARM_AM::sub;
- unsigned Amt = ARM_AM::getAM3Offset(OffImm);
- if (OffReg == 0)
- // Immediate is 8-bits. It's guaranteed to fit in a so_imm operand.
- UpdateMI = BuildMI(MF, get(isSub ? ARM::SUBri : ARM::ADDri), WBReg)
- .addReg(BaseReg).addImm(Amt)
- .addImm(Pred).addReg(0).addReg(0);
- else
- UpdateMI = BuildMI(MF, get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg)
- .addReg(BaseReg).addReg(OffReg)
- .addImm(Pred).addReg(0).addReg(0);
- break;
- }
- }
-
- std::vector<MachineInstr*> NewMIs;
- if (isPre) {
- if (isLoad)
- MemMI = BuildMI(MF, get(MemOpc), MI->getOperand(0).getReg())
- .addReg(WBReg).addReg(0).addImm(0).addImm(Pred);
- else
- MemMI = BuildMI(MF, get(MemOpc)).addReg(MI->getOperand(1).getReg())
- .addReg(WBReg).addReg(0).addImm(0).addImm(Pred);
- NewMIs.push_back(MemMI);
- NewMIs.push_back(UpdateMI);
- } else {
- if (isLoad)
- MemMI = BuildMI(MF, get(MemOpc), MI->getOperand(0).getReg())
- .addReg(BaseReg).addReg(0).addImm(0).addImm(Pred);
- else
- MemMI = BuildMI(MF, get(MemOpc)).addReg(MI->getOperand(1).getReg())
- .addReg(BaseReg).addReg(0).addImm(0).addImm(Pred);
- if (WB.isDead())
- UpdateMI->getOperand(0).setIsDead();
- NewMIs.push_back(UpdateMI);
- NewMIs.push_back(MemMI);
- }
-
- // Transfer LiveVariables states, kill / dead info.
- if (LV) {
- for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
- MachineOperand &MO = MI->getOperand(i);
- if (MO.isReg() && MO.getReg() &&
- TargetRegisterInfo::isVirtualRegister(MO.getReg())) {
- unsigned Reg = MO.getReg();
-
- LiveVariables::VarInfo &VI = LV->getVarInfo(Reg);
- if (MO.isDef()) {
- MachineInstr *NewMI = (Reg == WBReg) ? UpdateMI : MemMI;
- if (MO.isDead())
- LV->addVirtualRegisterDead(Reg, NewMI);
- }
- if (MO.isUse() && MO.isKill()) {
- for (unsigned j = 0; j < 2; ++j) {
- // Look at the two new MI's in reverse order.
- MachineInstr *NewMI = NewMIs[j];
- if (!NewMI->readsRegister(Reg))
- continue;
- LV->addVirtualRegisterKilled(Reg, NewMI);
- if (VI.removeKill(MI))
- VI.Kills.push_back(NewMI);
- break;
- }
- }
- }
- }
- }
-
- MFI->insert(MBBI, NewMIs[1]);
- MFI->insert(MBBI, NewMIs[0]);
- return NewMIs[0];
-}
-
-// Branch analysis.
-bool ARMInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB,
- MachineBasicBlock *&FBB,
- SmallVectorImpl<MachineOperand> &Cond) const {
- // If the block has no terminators, it just falls into the block after it.
- MachineBasicBlock::iterator I = MBB.end();
- if (I == MBB.begin() || !isUnpredicatedTerminator(--I))
- return false;
-
- // Get the last instruction in the block.
- MachineInstr *LastInst = I;
-
- // If there is only one terminator instruction, process it.
- unsigned LastOpc = LastInst->getOpcode();
- if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) {
- if (LastOpc == ARM::B || LastOpc == ARM::tB) {
- TBB = LastInst->getOperand(0).getMBB();
- return false;
- }
- if (LastOpc == ARM::Bcc || LastOpc == ARM::tBcc) {
- // Block ends with fall-through condbranch.
- TBB = LastInst->getOperand(0).getMBB();
- Cond.push_back(LastInst->getOperand(1));
- Cond.push_back(LastInst->getOperand(2));
- return false;
- }
- return true; // Can't handle indirect branch.
- }
-
- // Get the instruction before it if it is a terminator.
- MachineInstr *SecondLastInst = I;
-
- // If there are three terminators, we don't know what sort of block this is.
- if (SecondLastInst && I != MBB.begin() && isUnpredicatedTerminator(--I))
- return true;
-
- // If the block ends with ARM::B/ARM::tB and a ARM::Bcc/ARM::tBcc, handle it.
- unsigned SecondLastOpc = SecondLastInst->getOpcode();
- if ((SecondLastOpc == ARM::Bcc && LastOpc == ARM::B) ||
- (SecondLastOpc == ARM::tBcc && LastOpc == ARM::tB)) {
- TBB = SecondLastInst->getOperand(0).getMBB();
- Cond.push_back(SecondLastInst->getOperand(1));
- Cond.push_back(SecondLastInst->getOperand(2));
- FBB = LastInst->getOperand(0).getMBB();
- return false;
- }
-
- // If the block ends with two unconditional branches, handle it. The second
- // one is not executed, so remove it.
- if ((SecondLastOpc == ARM::B || SecondLastOpc==ARM::tB) &&
- (LastOpc == ARM::B || LastOpc == ARM::tB)) {
- TBB = SecondLastInst->getOperand(0).getMBB();
- I = LastInst;
- I->eraseFromParent();
- return false;
- }
-
- // Likewise if it ends with a branch table followed by an unconditional branch.
- // The branch folder can create these, and we must get rid of them for
- // correctness of Thumb constant islands.
- if ((SecondLastOpc == ARM::BR_JTr || SecondLastOpc==ARM::BR_JTm ||
- SecondLastOpc == ARM::BR_JTadd || SecondLastOpc==ARM::tBR_JTr) &&
- (LastOpc == ARM::B || LastOpc == ARM::tB)) {
- I = LastInst;
- I->eraseFromParent();
- return true;
- }
-
- // Otherwise, can't handle this.
- return true;
-}
-
-
-unsigned ARMInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const {
- MachineFunction &MF = *MBB.getParent();
- ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
- int BOpc = AFI->isThumbFunction() ? ARM::tB : ARM::B;
- int BccOpc = AFI->isThumbFunction() ? ARM::tBcc : ARM::Bcc;
-
- MachineBasicBlock::iterator I = MBB.end();
- if (I == MBB.begin()) return 0;
- --I;
- if (I->getOpcode() != BOpc && I->getOpcode() != BccOpc)
- return 0;
-
- // Remove the branch.
- I->eraseFromParent();
-
- I = MBB.end();
-
- if (I == MBB.begin()) return 1;
- --I;
- if (I->getOpcode() != BccOpc)
- return 1;
-
- // Remove the branch.
- I->eraseFromParent();
- return 2;
-}
-
-unsigned ARMInstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
- MachineBasicBlock *FBB,
- const SmallVectorImpl<MachineOperand> &Cond) const {
- MachineFunction &MF = *MBB.getParent();
- ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
- int BOpc = AFI->isThumbFunction() ? ARM::tB : ARM::B;
- int BccOpc = AFI->isThumbFunction() ? ARM::tBcc : ARM::Bcc;
-
- // Shouldn't be a fall through.
- assert(TBB && "InsertBranch must not be told to insert a fallthrough");
- assert((Cond.size() == 2 || Cond.size() == 0) &&
- "ARM branch conditions have two components!");
-
- if (FBB == 0) {
- if (Cond.empty()) // Unconditional branch?
- BuildMI(&MBB, get(BOpc)).addMBB(TBB);