//===-- ARMBaseInstrInfo.cpp - ARM Instruction Information ----------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file contains the Base ARM implementation of the TargetInstrInfo class. // //===----------------------------------------------------------------------===// #include "ARM.h" #include "ARMBaseInstrInfo.h" #include "ARMBaseRegisterInfo.h" #include "ARMConstantPoolValue.h" #include "ARMFeatures.h" #include "ARMHazardRecognizer.h" #include "ARMMachineFunctionInfo.h" #include "MCTargetDesc/ARMAddressingModes.h" #include "llvm/ADT/STLExtras.h" #include "llvm/CodeGen/LiveVariables.h" #include "llvm/CodeGen/MachineConstantPool.h" #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineJumpTableInfo.h" #include "llvm/CodeGen/MachineMemOperand.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/SelectionDAGNodes.h" #include "llvm/CodeGen/TargetSchedule.h" #include "llvm/IR/Constants.h" #include "llvm/IR/Function.h" #include "llvm/IR/GlobalValue.h" #include "llvm/MC/MCAsmInfo.h" #include "llvm/MC/MCExpr.h" #include "llvm/Support/BranchProbability.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/raw_ostream.h" using namespace llvm; #define DEBUG_TYPE "arm-instrinfo" #define GET_INSTRINFO_CTOR_DTOR #include "ARMGenInstrInfo.inc" static cl::opt EnableARM3Addr("enable-arm-3-addr-conv", cl::Hidden, cl::desc("Enable ARM 2-addr to 3-addr conv")); static cl::opt WidenVMOVS("widen-vmovs", cl::Hidden, cl::init(true), cl::desc("Widen ARM vmovs to vmovd when possible")); static cl::opt SwiftPartialUpdateClearance("swift-partial-update-clearance", cl::Hidden, cl::init(12), cl::desc("Clearance before partial register updates")); /// ARM_MLxEntry - Record information about MLA / MLS instructions. struct ARM_MLxEntry { uint16_t MLxOpc; // MLA / MLS opcode uint16_t MulOpc; // Expanded multiplication opcode uint16_t AddSubOpc; // Expanded add / sub opcode bool NegAcc; // True if the acc is negated before the add / sub. bool HasLane; // True if instruction has an extra "lane" operand. }; static const ARM_MLxEntry ARM_MLxTable[] = { // MLxOpc, MulOpc, AddSubOpc, NegAcc, HasLane // fp scalar ops { ARM::VMLAS, ARM::VMULS, ARM::VADDS, false, false }, { ARM::VMLSS, ARM::VMULS, ARM::VSUBS, false, false }, { ARM::VMLAD, ARM::VMULD, ARM::VADDD, false, false }, { ARM::VMLSD, ARM::VMULD, ARM::VSUBD, false, false }, { ARM::VNMLAS, ARM::VNMULS, ARM::VSUBS, true, false }, { ARM::VNMLSS, ARM::VMULS, ARM::VSUBS, true, false }, { ARM::VNMLAD, ARM::VNMULD, ARM::VSUBD, true, false }, { ARM::VNMLSD, ARM::VMULD, ARM::VSUBD, true, false }, // fp SIMD ops { ARM::VMLAfd, ARM::VMULfd, ARM::VADDfd, false, false }, { ARM::VMLSfd, ARM::VMULfd, ARM::VSUBfd, false, false }, { ARM::VMLAfq, ARM::VMULfq, ARM::VADDfq, false, false }, { ARM::VMLSfq, ARM::VMULfq, ARM::VSUBfq, false, false }, { ARM::VMLAslfd, ARM::VMULslfd, ARM::VADDfd, false, true }, { ARM::VMLSslfd, ARM::VMULslfd, ARM::VSUBfd, false, true }, { ARM::VMLAslfq, ARM::VMULslfq, ARM::VADDfq, false, true }, { ARM::VMLSslfq, ARM::VMULslfq, ARM::VSUBfq, false, true }, }; ARMBaseInstrInfo::ARMBaseInstrInfo(const ARMSubtarget& STI) : ARMGenInstrInfo(ARM::ADJCALLSTACKDOWN, ARM::ADJCALLSTACKUP), Subtarget(STI) { for (unsigned i = 0, e = array_lengthof(ARM_MLxTable); i != e; ++i) { if (!MLxEntryMap.insert(std::make_pair(ARM_MLxTable[i].MLxOpc, i)).second) assert(false && "Duplicated entries?"); MLxHazardOpcodes.insert(ARM_MLxTable[i].AddSubOpc); MLxHazardOpcodes.insert(ARM_MLxTable[i].MulOpc); } } // Use a ScoreboardHazardRecognizer for prepass ARM scheduling. TargetInstrImpl // currently defaults to no prepass hazard recognizer. ScheduleHazardRecognizer * ARMBaseInstrInfo::CreateTargetHazardRecognizer(const TargetSubtargetInfo *STI, const ScheduleDAG *DAG) const { if (usePreRAHazardRecognizer()) { const InstrItineraryData *II = static_cast(STI)->getInstrItineraryData(); return new ScoreboardHazardRecognizer(II, DAG, "pre-RA-sched"); } return TargetInstrInfo::CreateTargetHazardRecognizer(STI, DAG); } ScheduleHazardRecognizer *ARMBaseInstrInfo:: CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II, const ScheduleDAG *DAG) const { if (Subtarget.isThumb2() || Subtarget.hasVFP2()) return (ScheduleHazardRecognizer *)new ARMHazardRecognizer(II, DAG); return TargetInstrInfo::CreateTargetPostRAHazardRecognizer(II, DAG); } MachineInstr * ARMBaseInstrInfo::convertToThreeAddress(MachineFunction::iterator &MFI, MachineBasicBlock::iterator &MBBI, LiveVariables *LV) const { // FIXME: Thumb2 support. if (!EnableARM3Addr) return nullptr; MachineInstr *MI = MBBI; MachineFunction &MF = *MI->getParent()->getParent(); uint64_t TSFlags = MI->getDesc().TSFlags; bool isPre = false; switch ((TSFlags & ARMII::IndexModeMask) >> ARMII::IndexModeShift) { default: return nullptr; case ARMII::IndexModePre: isPre = true; break; case ARMII::IndexModePost: break; } // Try splitting an indexed load/store to an un-indexed one plus an add/sub // operation. unsigned MemOpc = getUnindexedOpcode(MI->getOpcode()); if (MemOpc == 0) return nullptr; MachineInstr *UpdateMI = nullptr; MachineInstr *MemMI = nullptr; unsigned AddrMode = (TSFlags & ARMII::AddrModeMask); const MCInstrDesc &MCID = MI->getDesc(); unsigned NumOps = MCID.getNumOperands(); bool isLoad = !MI->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: llvm_unreachable("Unknown indexed op!"); case ARMII::AddrMode2: { bool isSub = ARM_AM::getAM2Op(OffImm) == ARM_AM::sub; unsigned Amt = ARM_AM::getAM2Offset(OffImm); if (OffReg == 0) { if (ARM_AM::getSOImmVal(Amt) == -1) // Can't encode it in a so_imm operand. This transformation will // add more than 1 instruction. Abandon! return nullptr; UpdateMI = BuildMI(MF, MI->getDebugLoc(), get(isSub ? ARM::SUBri : ARM::ADDri), WBReg) .addReg(BaseReg).addImm(Amt) .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, MI->getDebugLoc(), get(isSub ? ARM::SUBrsi : ARM::ADDrsi), WBReg) .addReg(BaseReg).addReg(OffReg).addReg(0).addImm(SOOpc) .addImm(Pred).addReg(0).addReg(0); } else UpdateMI = BuildMI(MF, MI->getDebugLoc(), 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, MI->getDebugLoc(), get(isSub ? ARM::SUBri : ARM::ADDri), WBReg) .addReg(BaseReg).addImm(Amt) .addImm(Pred).addReg(0).addReg(0); else UpdateMI = BuildMI(MF, MI->getDebugLoc(), get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg) .addReg(BaseReg).addReg(OffReg) .addImm(Pred).addReg(0).addReg(0); break; } } std::vector NewMIs; if (isPre) { if (isLoad) MemMI = BuildMI(MF, MI->getDebugLoc(), get(MemOpc), MI->getOperand(0).getReg()) .addReg(WBReg).addImm(0).addImm(Pred); else MemMI = BuildMI(MF, MI->getDebugLoc(), 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, MI->getDebugLoc(), get(MemOpc), MI->getOperand(0).getReg()) .addReg(BaseReg).addImm(0).addImm(Pred); else MemMI = BuildMI(MF, MI->getDebugLoc(), 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() && 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 ARMBaseInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB, MachineBasicBlock *&FBB, SmallVectorImpl &Cond, bool AllowModify) const { TBB = nullptr; FBB = nullptr; MachineBasicBlock::iterator I = MBB.end(); if (I == MBB.begin()) return false; // Empty blocks are easy. --I; // Walk backwards from the end of the basic block until the branch is // analyzed or we give up. while (isPredicated(I) || I->isTerminator() || I->isDebugValue()) { // Flag to be raised on unanalyzeable instructions. This is useful in cases // where we want to clean up on the end of the basic block before we bail // out. bool CantAnalyze = false; // Skip over DEBUG values and predicated nonterminators. while (I->isDebugValue() || !I->isTerminator()) { if (I == MBB.begin()) return false; --I; } if (isIndirectBranchOpcode(I->getOpcode()) || isJumpTableBranchOpcode(I->getOpcode())) { // Indirect branches and jump tables can't be analyzed, but we still want // to clean up any instructions at the tail of the basic block. CantAnalyze = true; } else if (isUncondBranchOpcode(I->getOpcode())) { TBB = I->getOperand(0).getMBB(); } else if (isCondBranchOpcode(I->getOpcode())) { // Bail out if we encounter multiple conditional branches. if (!Cond.empty()) return true; assert(!FBB && "FBB should have been null."); FBB = TBB; TBB = I->getOperand(0).getMBB(); Cond.push_back(I->getOperand(1)); Cond.push_back(I->getOperand(2)); } else if (I->isReturn()) { // Returns can't be analyzed, but we should run cleanup. CantAnalyze = !isPredicated(I); } else { // We encountered other unrecognized terminator. Bail out immediately. return true; } // Cleanup code - to be run for unpredicated unconditional branches and // returns. if (!isPredicated(I) && (isUncondBranchOpcode(I->getOpcode()) || isIndirectBranchOpcode(I->getOpcode()) || isJumpTableBranchOpcode(I->getOpcode()) || I->isReturn())) { // Forget any previous condition branch information - it no longer applies. Cond.clear(); FBB = nullptr; // If we can modify the function, delete everything below this // unconditional branch. if (AllowModify) { MachineBasicBlock::iterator DI = std::next(I); while (DI != MBB.end()) { MachineInstr *InstToDelete = DI; ++DI; InstToDelete->eraseFromParent(); } } } if (CantAnalyze) return true; if (I == MBB.begin()) return false; --I; } // We made it past the terminators without bailing out - we must have // analyzed this branch successfully. return false; } unsigned ARMBaseInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const { MachineBasicBlock::iterator I = MBB.end(); if (I == MBB.begin()) return 0; --I; while (I->isDebugValue()) { if (I == MBB.begin()) return 0; --I; } if (!isUncondBranchOpcode(I->getOpcode()) && !isCondBranchOpcode(I->getOpcode())) return 0; // Remove the branch. I->eraseFromParent(); I = MBB.end(); if (I == MBB.begin()) return 1; --I; if (!isCondBranchOpcode(I->getOpcode())) return 1; // Remove the branch. I->eraseFromParent(); return 2; } unsigned ARMBaseInstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB, MachineBasicBlock *FBB, ArrayRef Cond, DebugLoc DL) const { ARMFunctionInfo *AFI = MBB.getParent()->getInfo(); int BOpc = !AFI->isThumbFunction() ? ARM::B : (AFI->isThumb2Function() ? ARM::t2B : ARM::tB); int BccOpc = !AFI->isThumbFunction() ? ARM::Bcc : (AFI->isThumb2Function() ? ARM::t2Bcc : ARM::tBcc); bool isThumb = AFI->isThumbFunction() || AFI->isThumb2Function(); // 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!"); // For conditional branches, we use addOperand to preserve CPSR flags. if (!FBB) { if (Cond.empty()) { // Unconditional branch? if (isThumb) BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB).addImm(ARMCC::AL).addReg(0); else BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB); } else BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB) .addImm(Cond[0].getImm()).addOperand(Cond[1]); return 1; } // Two-way conditional branch. BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB) .addImm(Cond[0].getImm()).addOperand(Cond[1]); if (isThumb) BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB).addImm(ARMCC::AL).addReg(0); else BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB); return 2; } bool ARMBaseInstrInfo:: ReverseBranchCondition(SmallVectorImpl &Cond) const { ARMCC::CondCodes CC = (ARMCC::CondCodes)(int)Cond[0].getImm(); Cond[0].setImm(ARMCC::getOppositeCondition(CC)); return false; } bool ARMBaseInstrInfo::isPredicated(const MachineInstr *MI) const { if (MI->isBundle()) { MachineBasicBlock::const_instr_iterator I = MI; MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); while (++I != E && I->isInsideBundle()) { int PIdx = I->findFirstPredOperandIdx(); if (PIdx != -1 && I->getOperand(PIdx).getImm() != ARMCC::AL) return true; } return false; } int PIdx = MI->findFirstPredOperandIdx(); return PIdx != -1 && MI->getOperand(PIdx).getImm() != ARMCC::AL; } bool ARMBaseInstrInfo:: PredicateInstruction(MachineInstr *MI, ArrayRef Pred) const { unsigned Opc = MI->getOpcode(); if (isUncondBranchOpcode(Opc)) { MI->setDesc(get(getMatchingCondBranchOpcode(Opc))); MachineInstrBuilder(*MI->getParent()->getParent(), MI) .addImm(Pred[0].getImm()) .addReg(Pred[1].getReg()); return true; } int PIdx = MI->findFirstPredOperandIdx(); if (PIdx != -1) { MachineOperand &PMO = MI->getOperand(PIdx); PMO.setImm(Pred[0].getImm()); MI->getOperand(PIdx+1).setReg(Pred[1].getReg()); return true; } return false; } bool ARMBaseInstrInfo::SubsumesPredicate(ArrayRef Pred1, ArrayRef Pred2) const { if (Pred1.size() > 2 || Pred2.size() > 2) return false; ARMCC::CondCodes CC1 = (ARMCC::CondCodes)Pred1[0].getImm(); ARMCC::CondCodes CC2 = (ARMCC::CondCodes)Pred2[0].getImm(); if (CC1 == CC2) return true; switch (CC1) { default: return false; case ARMCC::AL: return true; case ARMCC::HS: return CC2 == ARMCC::HI; case ARMCC::LS: return CC2 == ARMCC::LO || CC2 == ARMCC::EQ; case ARMCC::GE: return CC2 == ARMCC::GT; case ARMCC::LE: return CC2 == ARMCC::LT; } } bool ARMBaseInstrInfo::DefinesPredicate(MachineInstr *MI, std::vector &Pred) const { bool Found = false; for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { const MachineOperand &MO = MI->getOperand(i); if ((MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) || (MO.isReg() && MO.isDef() && MO.getReg() == ARM::CPSR)) { Pred.push_back(MO); Found = true; } } return Found; } static bool isCPSRDefined(const MachineInstr *MI) { for (const auto &MO : MI->operands()) if (MO.isReg() && MO.getReg() == ARM::CPSR && MO.isDef()) return true; return false; } static bool isEligibleForITBlock(const MachineInstr *MI) { switch (MI->getOpcode()) { default: return true; case ARM::tADC: // ADC (register) T1 case ARM::tADDi3: // ADD (immediate) T1 case ARM::tADDi8: // ADD (immediate) T2 case ARM::tADDrr: // ADD (register) T1 case ARM::tAND: // AND (register) T1 case ARM::tASRri: // ASR (immediate) T1 case ARM::tASRrr: // ASR (register) T1 case ARM::tBIC: // BIC (register) T1 case ARM::tEOR: // EOR (register) T1 case ARM::tLSLri: // LSL (immediate) T1 case ARM::tLSLrr: // LSL (register) T1 case ARM::tLSRri: // LSR (immediate) T1 case ARM::tLSRrr: // LSR (register) T1 case ARM::tMUL: // MUL T1 case ARM::tMVN: // MVN (register) T1 case ARM::tORR: // ORR (register) T1 case ARM::tROR: // ROR (register) T1 case ARM::tRSB: // RSB (immediate) T1 case ARM::tSBC: // SBC (register) T1 case ARM::tSUBi3: // SUB (immediate) T1 case ARM::tSUBi8: // SUB (immediate) T2 case ARM::tSUBrr: // SUB (register) T1 return !isCPSRDefined(MI); } } /// isPredicable - Return true if the specified instruction can be predicated. /// By default, this returns true for every instruction with a /// PredicateOperand. bool ARMBaseInstrInfo::isPredicable(MachineInstr *MI) const { if (!MI->isPredicable()) return false; if (!isEligibleForITBlock(MI)) return false; ARMFunctionInfo *AFI = MI->getParent()->getParent()->getInfo(); if (AFI->isThumb2Function()) { if (getSubtarget().restrictIT()) return isV8EligibleForIT(MI); } else { // non-Thumb if ((MI->getDesc().TSFlags & ARMII::DomainMask) == ARMII::DomainNEON) return false; } return true; } namespace llvm { template <> bool IsCPSRDead(MachineInstr *MI) { for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { const MachineOperand &MO = MI->getOperand(i); if (!MO.isReg() || MO.isUndef() || MO.isUse()) continue; if (MO.getReg() != ARM::CPSR) continue; if (!MO.isDead()) return false; } // all definitions of CPSR are dead return true; } } /// GetInstSize - Return the size of the specified MachineInstr. /// unsigned ARMBaseInstrInfo::GetInstSizeInBytes(const MachineInstr *MI) const { const MachineBasicBlock &MBB = *MI->getParent(); const MachineFunction *MF = MBB.getParent(); const MCAsmInfo *MAI = MF->getTarget().getMCAsmInfo(); const MCInstrDesc &MCID = MI->getDesc(); if (MCID.getSize()) return MCID.getSize(); // If this machine instr is an inline asm, measure it. if (MI->getOpcode() == ARM::INLINEASM) return getInlineAsmLength(MI->getOperand(0).getSymbolName(), *MAI); unsigned Opc = MI->getOpcode(); switch (Opc) { default: // pseudo-instruction sizes are zero. return 0; case TargetOpcode::BUNDLE: return getInstBundleLength(MI); case ARM::MOVi16_ga_pcrel: case ARM::MOVTi16_ga_pcrel: case ARM::t2MOVi16_ga_pcrel: case ARM::t2MOVTi16_ga_pcrel: return 4; case ARM::MOVi32imm: case ARM::t2MOVi32imm: return 8; case ARM::CONSTPOOL_ENTRY: case ARM::JUMPTABLE_INSTS: case ARM::JUMPTABLE_ADDRS: case ARM::JUMPTABLE_TBB: case ARM::JUMPTABLE_TBH: // If this machine instr is a constant pool entry, its size is recorded as // operand #2. return MI->getOperand(2).getImm(); case ARM::Int_eh_sjlj_longjmp: return 16; case ARM::tInt_eh_sjlj_longjmp: return 10; case ARM::Int_eh_sjlj_setjmp: case ARM::Int_eh_sjlj_setjmp_nofp: return 20; case ARM::tInt_eh_sjlj_setjmp: case ARM::t2Int_eh_sjlj_setjmp: case ARM::t2Int_eh_sjlj_setjmp_nofp: return 12; case ARM::SPACE: return MI->getOperand(1).getImm(); } } unsigned ARMBaseInstrInfo::getInstBundleLength(const MachineInstr *MI) const { unsigned Size = 0; MachineBasicBlock::const_instr_iterator I = MI; MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); while (++I != E && I->isInsideBundle()) { assert(!I->isBundle() && "No nested bundle!"); Size += GetInstSizeInBytes(&*I); } return Size; } void ARMBaseInstrInfo::copyFromCPSR(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, unsigned DestReg, bool KillSrc, const ARMSubtarget &Subtarget) const { unsigned Opc = Subtarget.isThumb() ? (Subtarget.isMClass() ? ARM::t2MRS_M : ARM::t2MRS_AR) : ARM::MRS; MachineInstrBuilder MIB = BuildMI(MBB, I, I->getDebugLoc(), get(Opc), DestReg); // There is only 1 A/R class MRS instruction, and it always refers to // APSR. However, there are lots of other possibilities on M-class cores. if (Subtarget.isMClass()) MIB.addImm(0x800); AddDefaultPred(MIB); MIB.addReg(ARM::CPSR, RegState::Implicit | getKillRegState(KillSrc)); } void ARMBaseInstrInfo::copyToCPSR(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, unsigned SrcReg, bool KillSrc, const ARMSubtarget &Subtarget) const { unsigned Opc = Subtarget.isThumb() ? (Subtarget.isMClass() ? ARM::t2MSR_M : ARM::t2MSR_AR) : ARM::MSR; MachineInstrBuilder MIB = BuildMI(MBB, I, I->getDebugLoc(), get(Opc)); if (Subtarget.isMClass()) MIB.addImm(0x800); else MIB.addImm(8); MIB.addReg(SrcReg, getKillRegState(KillSrc)); AddDefaultPred(MIB); MIB.addReg(ARM::CPSR, RegState::Implicit | RegState::Define); } void ARMBaseInstrInfo::copyPhysReg(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, DebugLoc DL, unsigned DestReg, unsigned SrcReg, bool KillSrc) const { bool GPRDest = ARM::GPRRegClass.contains(DestReg); bool GPRSrc = ARM::GPRRegClass.contains(SrcReg); if (GPRDest && GPRSrc) { AddDefaultCC(AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::MOVr), DestReg) .addReg(SrcReg, getKillRegState(KillSrc)))); return; } bool SPRDest = ARM::SPRRegClass.contains(DestReg); bool SPRSrc = ARM::SPRRegClass.contains(SrcReg); unsigned Opc = 0; if (SPRDest && SPRSrc) Opc = ARM::VMOVS; else if (GPRDest && SPRSrc) Opc = ARM::VMOVRS; else if (SPRDest && GPRSrc) Opc = ARM::VMOVSR; else if (ARM::DPRRegClass.contains(DestReg, SrcReg) && !Subtarget.isFPOnlySP()) Opc = ARM::VMOVD; else if (ARM::QPRRegClass.contains(DestReg, SrcReg)) Opc = ARM::VORRq; if (Opc) { MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(Opc), DestReg); MIB.addReg(SrcReg, getKillRegState(KillSrc)); if (Opc == ARM::VORRq) MIB.addReg(SrcReg, getKillRegState(KillSrc)); AddDefaultPred(MIB); return; } // Handle register classes that require multiple instructions. unsigned BeginIdx = 0; unsigned SubRegs = 0; int Spacing = 1; // Use VORRq when possible. if (ARM::QQPRRegClass.contains(DestReg, SrcReg)) { Opc = ARM::VORRq; BeginIdx = ARM::qsub_0; SubRegs = 2; } else if (ARM::QQQQPRRegClass.contains(DestReg, SrcReg)) { Opc = ARM::VORRq; BeginIdx = ARM::qsub_0; SubRegs = 4; // Fall back to VMOVD. } else if (ARM::DPairRegClass.contains(DestReg, SrcReg)) { Opc = ARM::VMOVD; BeginIdx = ARM::dsub_0; SubRegs = 2; } else if (ARM::DTripleRegClass.contains(DestReg, SrcReg)) { Opc = ARM::VMOVD; BeginIdx = ARM::dsub_0; SubRegs = 3; } else if (ARM::DQuadRegClass.contains(DestReg, SrcReg)) { Opc = ARM::VMOVD; BeginIdx = ARM::dsub_0; SubRegs = 4; } else if (ARM::GPRPairRegClass.contains(DestReg, SrcReg)) { Opc = Subtarget.isThumb2() ? ARM::tMOVr : ARM::MOVr; BeginIdx = ARM::gsub_0; SubRegs = 2; } else if (ARM::DPairSpcRegClass.contains(DestReg, SrcReg)) { Opc = ARM::VMOVD; BeginIdx = ARM::dsub_0; SubRegs = 2; Spacing = 2; } else if (ARM::DTripleSpcRegClass.contains(DestReg, SrcReg)) { Opc = ARM::VMOVD; BeginIdx = ARM::dsub_0; SubRegs = 3; Spacing = 2; } else if (ARM::DQuadSpcRegClass.contains(DestReg, SrcReg)) { Opc = ARM::VMOVD; BeginIdx = ARM::dsub_0; SubRegs = 4; Spacing = 2; } else if (ARM::DPRRegClass.contains(DestReg, SrcReg) && Subtarget.isFPOnlySP()) { Opc = ARM::VMOVS; BeginIdx = ARM::ssub_0; SubRegs = 2; } else if (SrcReg == ARM::CPSR) { copyFromCPSR(MBB, I, DestReg, KillSrc, Subtarget); return; } else if (DestReg == ARM::CPSR) { copyToCPSR(MBB, I, SrcReg, KillSrc, Subtarget); return; } assert(Opc && "Impossible reg-to-reg copy"); const TargetRegisterInfo *TRI = &getRegisterInfo(); MachineInstrBuilder Mov; // Copy register tuples backward when the first Dest reg overlaps with SrcReg. if (TRI->regsOverlap(SrcReg, TRI->getSubReg(DestReg, BeginIdx))) { BeginIdx = BeginIdx + ((SubRegs - 1) * Spacing); Spacing = -Spacing; } #ifndef NDEBUG SmallSet DstRegs; #endif for (unsigned i = 0; i != SubRegs; ++i) { unsigned Dst = TRI->getSubReg(DestReg, BeginIdx + i * Spacing); unsigned Src = TRI->getSubReg(SrcReg, BeginIdx + i * Spacing); assert(Dst && Src && "Bad sub-register"); #ifndef NDEBUG assert(!DstRegs.count(Src) && "destructive vector copy"); DstRegs.insert(Dst); #endif Mov = BuildMI(MBB, I, I->getDebugLoc(), get(Opc), Dst).addReg(Src); // VORR takes two source operands. if (Opc == ARM::VORRq) Mov.addReg(Src); Mov = AddDefaultPred(Mov); // MOVr can set CC. if (Opc == ARM::MOVr) Mov = AddDefaultCC(Mov); } // Add implicit super-register defs and kills to the last instruction. Mov->addRegisterDefined(DestReg, TRI); if (KillSrc) Mov->addRegisterKilled(SrcReg, TRI); } const MachineInstrBuilder & ARMBaseInstrInfo::AddDReg(MachineInstrBuilder &MIB, unsigned Reg, unsigned SubIdx, unsigned State, const TargetRegisterInfo *TRI) const { if (!SubIdx) return MIB.addReg(Reg, State); if (TargetRegisterInfo::isPhysicalRegister(Reg)) return MIB.addReg(TRI->getSubReg(Reg, SubIdx), State); return MIB.addReg(Reg, State, SubIdx); } void ARMBaseInstrInfo:: storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, unsigned SrcReg, bool isKill, int FI, const TargetRegisterClass *RC, const TargetRegisterInfo *TRI) const { DebugLoc DL; if (I != MBB.end()) DL = I->getDebugLoc(); MachineFunction &MF = *MBB.getParent(); MachineFrameInfo &MFI = *MF.getFrameInfo(); unsigned Align = MFI.getObjectAlignment(FI); MachineMemOperand *MMO = MF.getMachineMemOperand(MachinePointerInfo::getFixedStack(FI), MachineMemOperand::MOStore, MFI.getObjectSize(FI), Align); switch (RC->getSize()) { case 4: if (ARM::GPRRegClass.hasSubClassEq(RC)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STRi12)) .addReg(SrcReg, getKillRegState(isKill)) .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); } else if (ARM::SPRRegClass.hasSubClassEq(RC)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRS)) .addReg(SrcReg, getKillRegState(isKill)) .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); } else llvm_unreachable("Unknown reg class!"); break; case 8: if (ARM::DPRRegClass.hasSubClassEq(RC)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRD)) .addReg(SrcReg, getKillRegState(isKill)) .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) { if (Subtarget.hasV5TEOps()) { MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(ARM::STRD)); AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI); AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI); MIB.addFrameIndex(FI).addReg(0).addImm(0).addMemOperand(MMO); AddDefaultPred(MIB); } else { // Fallback to STM instruction, which has existed since the dawn of // time. MachineInstrBuilder MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STMIA)) .addFrameIndex(FI).addMemOperand(MMO)); AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI); AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI); } } else llvm_unreachable("Unknown reg class!"); break; case 16: if (ARM::DPairRegClass.hasSubClassEq(RC)) { // Use aligned spills if the stack can be realigned. if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1q64)) .addFrameIndex(FI).addImm(16) .addReg(SrcReg, getKillRegState(isKill)) .addMemOperand(MMO)); } else { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMQIA)) .addReg(SrcReg, getKillRegState(isKill)) .addFrameIndex(FI) .addMemOperand(MMO)); } } else llvm_unreachable("Unknown reg class!"); break; case 24: if (ARM::DTripleRegClass.hasSubClassEq(RC)) { // Use aligned spills if the stack can be realigned. if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64TPseudo)) .addFrameIndex(FI).addImm(16) .addReg(SrcReg, getKillRegState(isKill)) .addMemOperand(MMO)); } else { MachineInstrBuilder MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) .addFrameIndex(FI)) .addMemOperand(MMO); MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); } } else llvm_unreachable("Unknown reg class!"); break; case 32: if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) { if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { // FIXME: It's possible to only store part of the QQ register if the // spilled def has a sub-register index. AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64QPseudo)) .addFrameIndex(FI).addImm(16) .addReg(SrcReg, getKillRegState(isKill)) .addMemOperand(MMO)); } else { MachineInstrBuilder MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) .addFrameIndex(FI)) .addMemOperand(MMO); MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI); } } else llvm_unreachable("Unknown reg class!"); break; case 64: if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) { MachineInstrBuilder MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) .addFrameIndex(FI)) .addMemOperand(MMO); MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); MIB = AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI); MIB = AddDReg(MIB, SrcReg, ARM::dsub_4, 0, TRI); MIB = AddDReg(MIB, SrcReg, ARM::dsub_5, 0, TRI); MIB = AddDReg(MIB, SrcReg, ARM::dsub_6, 0, TRI); AddDReg(MIB, SrcReg, ARM::dsub_7, 0, TRI); } else llvm_unreachable("Unknown reg class!"); break; default: llvm_unreachable("Unknown reg class!"); } } unsigned ARMBaseInstrInfo::isStoreToStackSlot(const MachineInstr *MI, int &FrameIndex) const { switch (MI->getOpcode()) { default: break; case ARM::STRrs: case ARM::t2STRs: // FIXME: don't use t2STRs to access frame. if (MI->getOperand(1).isFI() && MI->getOperand(2).isReg() && MI->getOperand(3).isImm() && MI->getOperand(2).getReg() == 0 && MI->getOperand(3).getImm() == 0) { FrameIndex = MI->getOperand(1).getIndex(); return MI->getOperand(0).getReg(); } break; case ARM::STRi12: case ARM::t2STRi12: case ARM::tSTRspi: case ARM::VSTRD: case ARM::VSTRS: if (MI->getOperand(1).isFI() && MI->getOperand(2).isImm() && MI->getOperand(2).getImm() == 0) { FrameIndex = MI->getOperand(1).getIndex(); return MI->getOperand(0).getReg(); } break; case ARM::VST1q64: case ARM::VST1d64TPseudo: case ARM::VST1d64QPseudo: if (MI->getOperand(0).isFI() && MI->getOperand(2).getSubReg() == 0) { FrameIndex = MI->getOperand(0).getIndex(); return MI->getOperand(2).getReg(); } break; case ARM::VSTMQIA: if (MI->getOperand(1).isFI() && MI->getOperand(0).getSubReg() == 0) { FrameIndex = MI->getOperand(1).getIndex(); return MI->getOperand(0).getReg(); } break; } return 0; } unsigned ARMBaseInstrInfo::isStoreToStackSlotPostFE(const MachineInstr *MI, int &FrameIndex) const { const MachineMemOperand *Dummy; return MI->mayStore() && hasStoreToStackSlot(MI, Dummy, FrameIndex); } void ARMBaseInstrInfo:: loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, unsigned DestReg, int FI, const TargetRegisterClass *RC, const TargetRegisterInfo *TRI) const { DebugLoc DL; if (I != MBB.end()) DL = I->getDebugLoc(); MachineFunction &MF = *MBB.getParent(); MachineFrameInfo &MFI = *MF.getFrameInfo(); unsigned Align = MFI.getObjectAlignment(FI); MachineMemOperand *MMO = MF.getMachineMemOperand( MachinePointerInfo::getFixedStack(FI), MachineMemOperand::MOLoad, MFI.getObjectSize(FI), Align); switch (RC->getSize()) { case 4: if (ARM::GPRRegClass.hasSubClassEq(RC)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::LDRi12), DestReg) .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); } else if (ARM::SPRRegClass.hasSubClassEq(RC)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRS), DestReg) .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); } else llvm_unreachable("Unknown reg class!"); break; case 8: if (ARM::DPRRegClass.hasSubClassEq(RC)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRD), DestReg) .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) { MachineInstrBuilder MIB; if (Subtarget.hasV5TEOps()) { MIB = BuildMI(MBB, I, DL, get(ARM::LDRD)); AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI); AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI); MIB.addFrameIndex(FI).addReg(0).addImm(0).addMemOperand(MMO); AddDefaultPred(MIB); } else { // Fallback to LDM instruction, which has existed since the dawn of // time. MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::LDMIA)) .addFrameIndex(FI).addMemOperand(MMO)); MIB = AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI); } if (TargetRegisterInfo::isPhysicalRegister(DestReg)) MIB.addReg(DestReg, RegState::ImplicitDefine); } else llvm_unreachable("Unknown reg class!"); break; case 16: if (ARM::DPairRegClass.hasSubClassEq(RC)) { if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1q64), DestReg) .addFrameIndex(FI).addImm(16) .addMemOperand(MMO)); } else { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMQIA), DestReg) .addFrameIndex(FI) .addMemOperand(MMO)); } } else llvm_unreachable("Unknown reg class!"); break; case 24: if (ARM::DTripleRegClass.hasSubClassEq(RC)) { if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64TPseudo), DestReg) .addFrameIndex(FI).addImm(16) .addMemOperand(MMO)); } else { MachineInstrBuilder MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) .addFrameIndex(FI) .addMemOperand(MMO)); MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); if (TargetRegisterInfo::isPhysicalRegister(DestReg)) MIB.addReg(DestReg, RegState::ImplicitDefine); } } else llvm_unreachable("Unknown reg class!"); break; case 32: if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) { if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64QPseudo), DestReg) .addFrameIndex(FI).addImm(16) .addMemOperand(MMO)); } else { MachineInstrBuilder MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) .addFrameIndex(FI)) .addMemOperand(MMO); MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI); if (TargetRegisterInfo::isPhysicalRegister(DestReg)) MIB.addReg(DestReg, RegState::ImplicitDefine); } } else llvm_unreachable("Unknown reg class!"); break; case 64: if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) { MachineInstrBuilder MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) .addFrameIndex(FI)) .addMemOperand(MMO); MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_4, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_5, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_6, RegState::DefineNoRead, TRI); MIB = AddDReg(MIB, DestReg, ARM::dsub_7, RegState::DefineNoRead, TRI); if (TargetRegisterInfo::isPhysicalRegister(DestReg)) MIB.addReg(DestReg, RegState::ImplicitDefine); } else llvm_unreachable("Unknown reg class!"); break; default: llvm_unreachable("Unknown regclass!"); } } unsigned ARMBaseInstrInfo::isLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) const { switch (MI->getOpcode()) { default: break; case ARM::LDRrs: case ARM::t2LDRs: // FIXME: don't use t2LDRs to access frame. if (MI->getOperand(1).isFI() && MI->getOperand(2).isReg() && MI->getOperand(3).isImm() && MI->getOperand(2).getReg() == 0 && MI->getOperand(3).getImm() == 0) { FrameIndex = MI->getOperand(1).getIndex(); return MI->getOperand(0).getReg(); } break; case ARM::LDRi12: case ARM::t2LDRi12: case ARM::tLDRspi: case ARM::VLDRD: case ARM::VLDRS: if (MI->getOperand(1).isFI() && MI->getOperand(2).isImm() && MI->getOperand(2).getImm() == 0) { FrameIndex = MI->getOperand(1).getIndex(); return MI->getOperand(0).getReg(); } break; case ARM::VLD1q64: case ARM::VLD1d64TPseudo: case ARM::VLD1d64QPseudo: if (MI->getOperand(1).isFI() && MI->getOperand(0).getSubReg() == 0) { FrameIndex = MI->getOperand(1).getIndex(); return MI->getOperand(0).getReg(); } break; case ARM::VLDMQIA: if (MI->getOperand(1).isFI() && MI->getOperand(0).getSubReg() == 0) { FrameIndex = MI->getOperand(1).getIndex(); return MI->getOperand(0).getReg(); } break; } return 0; } unsigned ARMBaseInstrInfo::isLoadFromStackSlotPostFE(const MachineInstr *MI, int &FrameIndex) const { const MachineMemOperand *Dummy; return MI->mayLoad() && hasLoadFromStackSlot(MI, Dummy, FrameIndex); } bool ARMBaseInstrInfo::expandPostRAPseudo(MachineBasicBlock::iterator MI) const { MachineFunction &MF = *MI->getParent()->getParent(); Reloc::Model RM = MF.getTarget().getRelocationModel(); if (MI->getOpcode() == TargetOpcode::LOAD_STACK_GUARD) { assert(getSubtarget().getTargetTriple().getObjectFormat() == Triple::MachO && "LOAD_STACK_GUARD currently supported only for MachO."); expandLoadStackGuard(MI, RM); MI->getParent()->erase(MI); return true; } // This hook gets to expand COPY instructions before they become // copyPhysReg() calls. Look for VMOVS instructions that can legally be // widened to VMOVD. We prefer the VMOVD when possible because it may be // changed into a VORR that can go down the NEON pipeline. if (!WidenVMOVS || !MI->isCopy() || Subtarget.isCortexA15() || Subtarget.isFPOnlySP()) return false; // Look for a copy between even S-registers. That is where we keep floats // when using NEON v2f32 instructions for f32 arithmetic. unsigned DstRegS = MI->getOperand(0).getReg(); unsigned SrcRegS = MI->getOperand(1).getReg(); if (!ARM::SPRRegClass.contains(DstRegS, SrcRegS)) return false; const TargetRegisterInfo *TRI = &getRegisterInfo(); unsigned DstRegD = TRI->getMatchingSuperReg(DstRegS, ARM::ssub_0, &ARM::DPRRegClass); unsigned SrcRegD = TRI->getMatchingSuperReg(SrcRegS, ARM::ssub_0, &ARM::DPRRegClass); if (!DstRegD || !SrcRegD) return false; // We want to widen this into a DstRegD = VMOVD SrcRegD copy. This is only // legal if the COPY already defines the full DstRegD, and it isn't a // sub-register insertion. if (!MI->definesRegister(DstRegD, TRI) || MI->readsRegister(DstRegD, TRI)) return false; // A dead copy shouldn't show up here, but reject it just in case. if (MI->getOperand(0).isDead()) return false; // All clear, widen the COPY. DEBUG(dbgs() << "widening: " << *MI); MachineInstrBuilder MIB(*MI->getParent()->getParent(), MI); // Get rid of the old of DstRegD. Leave it if it defines a Q-reg // or some other super-register. int ImpDefIdx = MI->findRegisterDefOperandIdx(DstRegD); if (ImpDefIdx != -1) MI->RemoveOperand(ImpDefIdx); // Change the opcode and operands. MI->setDesc(get(ARM::VMOVD)); MI->getOperand(0).setReg(DstRegD); MI->getOperand(1).setReg(SrcRegD); AddDefaultPred(MIB); // We are now reading SrcRegD instead of SrcRegS. This may upset the // register scavenger and machine verifier, so we need to indicate that we // are reading an undefined value from SrcRegD, but a proper value from // SrcRegS. MI->getOperand(1).setIsUndef(); MIB.addReg(SrcRegS, RegState::Implicit); // SrcRegD may actually contain an unrelated value in the ssub_1 // sub-register. Don't kill it. Only kill the ssub_0 sub-register. if (MI->getOperand(1).isKill()) { MI->getOperand(1).setIsKill(false); MI->addRegisterKilled(SrcRegS, TRI, true); } DEBUG(dbgs() << "replaced by: " << *MI); return true; } /// Create a copy of a const pool value. Update CPI to the new index and return /// the label UID. static unsigned duplicateCPV(MachineFunction &MF, unsigned &CPI) { MachineConstantPool *MCP = MF.getConstantPool(); ARMFunctionInfo *AFI = MF.getInfo(); const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPI]; assert(MCPE.isMachineConstantPoolEntry() && "Expecting a machine constantpool entry!"); ARMConstantPoolValue *ACPV = static_cast(MCPE.Val.MachineCPVal); unsigned PCLabelId = AFI->createPICLabelUId(); ARMConstantPoolValue *NewCPV = nullptr; // FIXME: The below assumes PIC relocation model and that the function // is Thumb mode (t1 or t2). PCAdjustment would be 8 for ARM mode PIC, and // zero for non-PIC in ARM or Thumb. The callers are all of thumb LDR // instructions, so that's probably OK, but is PIC always correct when // we get here? if (ACPV->isGlobalValue()) NewCPV = ARMConstantPoolConstant:: Create(cast(ACPV)->getGV(), PCLabelId, ARMCP::CPValue, 4); else if (ACPV->isExtSymbol()) NewCPV = ARMConstantPoolSymbol:: Create(MF.getFunction()->getContext(), cast(ACPV)->getSymbol(), PCLabelId, 4); else if (ACPV->isBlockAddress()) NewCPV = ARMConstantPoolConstant:: Create(cast(ACPV)->getBlockAddress(), PCLabelId, ARMCP::CPBlockAddress, 4); else if (ACPV->isLSDA()) NewCPV = ARMConstantPoolConstant::Create(MF.getFunction(), PCLabelId, ARMCP::CPLSDA, 4); else if (ACPV->isMachineBasicBlock()) NewCPV = ARMConstantPoolMBB:: Create(MF.getFunction()->getContext(), cast(ACPV)->getMBB(), PCLabelId, 4); else llvm_unreachable("Unexpected ARM constantpool value type!!"); CPI = MCP->getConstantPoolIndex(NewCPV, MCPE.getAlignment()); return PCLabelId; } void ARMBaseInstrInfo:: reMaterialize(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, unsigned DestReg, unsigned SubIdx, const MachineInstr *Orig, const TargetRegisterInfo &TRI) const { unsigned Opcode = Orig->getOpcode(); switch (Opcode) { default: { MachineInstr *MI = MBB.getParent()->CloneMachineInstr(Orig); MI->substituteRegister(Orig->getOperand(0).getReg(), DestReg, SubIdx, TRI); MBB.insert(I, MI); break; } case ARM::tLDRpci_pic: case ARM::t2LDRpci_pic: { MachineFunction &MF = *MBB.getParent(); unsigned CPI = Orig->getOperand(1).getIndex(); unsigned PCLabelId = duplicateCPV(MF, CPI); MachineInstrBuilder MIB = BuildMI(MBB, I, Orig->getDebugLoc(), get(Opcode), DestReg) .addConstantPoolIndex(CPI).addImm(PCLabelId); MIB->setMemRefs(Orig->memoperands_begin(), Orig->memoperands_end()); break; } } } MachineInstr * ARMBaseInstrInfo::duplicate(MachineInstr *Orig, MachineFunction &MF) const { MachineInstr *MI = TargetInstrInfo::duplicate(Orig, MF); switch(Orig->getOpcode()) { case ARM::tLDRpci_pic: case ARM::t2LDRpci_pic: { unsigned CPI = Orig->getOperand(1).getIndex(); unsigned PCLabelId = duplicateCPV(MF, CPI); Orig->getOperand(1).setIndex(CPI); Orig->getOperand(2).setImm(PCLabelId); break; } } return MI; } bool ARMBaseInstrInfo::produceSameValue(const MachineInstr *MI0, const MachineInstr *MI1, const MachineRegisterInfo *MRI) const { unsigned Opcode = MI0->getOpcode(); if (Opcode == ARM::t2LDRpci || Opcode == ARM::t2LDRpci_pic || Opcode == ARM::tLDRpci || Opcode == ARM::tLDRpci_pic || Opcode == ARM::LDRLIT_ga_pcrel || Opcode == ARM::LDRLIT_ga_pcrel_ldr || Opcode == ARM::tLDRLIT_ga_pcrel || Opcode == ARM::MOV_ga_pcrel || Opcode == ARM::MOV_ga_pcrel_ldr || Opcode == ARM::t2MOV_ga_pcrel) { if (MI1->getOpcode() != Opcode) return false; if (MI0->getNumOperands() != MI1->getNumOperands()) return false; const MachineOperand &MO0 = MI0->getOperand(1); const MachineOperand &MO1 = MI1->getOperand(1); if (MO0.getOffset() != MO1.getOffset()) return false; if (Opcode == ARM::LDRLIT_ga_pcrel || Opcode == ARM::LDRLIT_ga_pcrel_ldr || Opcode == ARM::tLDRLIT_ga_pcrel || Opcode == ARM::MOV_ga_pcrel || Opcode == ARM::MOV_ga_pcrel_ldr || Opcode == ARM::t2MOV_ga_pcrel) // Ignore the PC labels. return MO0.getGlobal() == MO1.getGlobal(); const MachineFunction *MF = MI0->getParent()->getParent(); const MachineConstantPool *MCP = MF->getConstantPool(); int CPI0 = MO0.getIndex(); int CPI1 = MO1.getIndex(); const MachineConstantPoolEntry &MCPE0 = MCP->getConstants()[CPI0]; const MachineConstantPoolEntry &MCPE1 = MCP->getConstants()[CPI1]; bool isARMCP0 = MCPE0.isMachineConstantPoolEntry(); bool isARMCP1 = MCPE1.isMachineConstantPoolEntry(); if (isARMCP0 && isARMCP1) { ARMConstantPoolValue *ACPV0 = static_cast(MCPE0.Val.MachineCPVal); ARMConstantPoolValue *ACPV1 = static_cast(MCPE1.Val.MachineCPVal); return ACPV0->hasSameValue(ACPV1); } else if (!isARMCP0 && !isARMCP1) { return MCPE0.Val.ConstVal == MCPE1.Val.ConstVal; } return false; } else if (Opcode == ARM::PICLDR) { if (MI1->getOpcode() != Opcode) return false; if (MI0->getNumOperands() != MI1->getNumOperands()) return false; unsigned Addr0 = MI0->getOperand(1).getReg(); unsigned Addr1 = MI1->getOperand(1).getReg(); if (Addr0 != Addr1) { if (!MRI || !TargetRegisterInfo::isVirtualRegister(Addr0) || !TargetRegisterInfo::isVirtualRegister(Addr1)) return false; // This assumes SSA form. MachineInstr *Def0 = MRI->getVRegDef(Addr0); MachineInstr *Def1 = MRI->getVRegDef(Addr1); // Check if the loaded value, e.g. a constantpool of a global address, are // the same. if (!produceSameValue(Def0, Def1, MRI)) return false; } for (unsigned i = 3, e = MI0->getNumOperands(); i != e; ++i) { // %vreg12 = PICLDR %vreg11, 0, pred:14, pred:%noreg const MachineOperand &MO0 = MI0->getOperand(i); const MachineOperand &MO1 = MI1->getOperand(i); if (!MO0.isIdenticalTo(MO1)) return false; } return true; } return MI0->isIdenticalTo(MI1, MachineInstr::IgnoreVRegDefs); } /// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler to /// determine if two loads are loading from the same base address. It should /// only return true if the base pointers are the same and the only differences /// between the two addresses is the offset. It also returns the offsets by /// reference. /// /// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched /// is permanently disabled. bool ARMBaseInstrInfo::areLoadsFromSameBasePtr(SDNode *Load1, SDNode *Load2, int64_t &Offset1, int64_t &Offset2) const { // Don't worry about Thumb: just ARM and Thumb2. if (Subtarget.isThumb1Only()) return false; if (!Load1->isMachineOpcode() || !Load2->isMachineOpcode()) return false; switch (Load1->getMachineOpcode()) { default: return false; case ARM::LDRi12: case ARM::LDRBi12: case ARM::LDRD: case ARM::LDRH: case ARM::LDRSB: case ARM::LDRSH: case ARM::VLDRD: case ARM::VLDRS: case ARM::t2LDRi8: case ARM::t2LDRBi8: case ARM::t2LDRDi8: case ARM::t2LDRSHi8: case ARM::t2LDRi12: case ARM::t2LDRBi12: case ARM::t2LDRSHi12: break; } switch (Load2->getMachineOpcode()) { default: return false; case ARM::LDRi12: case ARM::LDRBi12: case ARM::LDRD: case ARM::LDRH: case ARM::LDRSB: case ARM::LDRSH: case ARM::VLDRD: case ARM::VLDRS: case ARM::t2LDRi8: case ARM::t2LDRBi8: case ARM::t2LDRSHi8: case ARM::t2LDRi12: case ARM::t2LDRBi12: case ARM::t2LDRSHi12: break; } // Check if base addresses and chain operands match. if (Load1->getOperand(0) != Load2->getOperand(0) || Load1->getOperand(4) != Load2->getOperand(4)) return false; // Index should be Reg0. if (Load1->getOperand(3) != Load2->getOperand(3)) return false; // Determine the offsets. if (isa(Load1->getOperand(1)) && isa(Load2->getOperand(1))) { Offset1 = cast(Load1->getOperand(1))->getSExtValue(); Offset2 = cast(Load2->getOperand(1))->getSExtValue(); return true; } return false; } /// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to /// determine (in conjunction with areLoadsFromSameBasePtr) if two loads should /// be scheduled togther. On some targets if two loads are loading from /// addresses in the same cache line, it's better if they are scheduled /// together. This function takes two integers that represent the load offsets /// from the common base address. It returns true if it decides it's desirable /// to schedule the two loads together. "NumLoads" is the number of loads that /// have already been scheduled after Load1. /// /// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched /// is permanently disabled. bool ARMBaseInstrInfo::shouldScheduleLoadsNear(SDNode *Load1, SDNode *Load2, int64_t Offset1, int64_t Offset2, unsigned NumLoads) const { // Don't worry about Thumb: just ARM and Thumb2. if (Subtarget.isThumb1Only()) return false; assert(Offset2 > Offset1); if ((Offset2 - Offset1) / 8 > 64) return false; // Check if the machine opcodes are different. If they are different // then we consider them to not be of the same base address, // EXCEPT in the case of Thumb2 byte loads where one is LDRBi8 and the other LDRBi12. // In this case, they are considered to be the same because they are different // encoding forms of the same basic instruction. if ((Load1->getMachineOpcode() != Load2->getMachineOpcode()) && !((Load1->getMachineOpcode() == ARM::t2LDRBi8 && Load2->getMachineOpcode() == ARM::t2LDRBi12) || (Load1->getMachineOpcode() == ARM::t2LDRBi12 && Load2->getMachineOpcode() == ARM::t2LDRBi8))) return false; // FIXME: overly conservative? // Four loads in a row should be sufficient. if (NumLoads >= 3) return false; return true; } bool ARMBaseInstrInfo::isSchedulingBoundary(const MachineInstr *MI, const MachineBasicBlock *MBB, const MachineFunction &MF) const { // Debug info is never a scheduling boundary. It's necessary to be explicit // due to the special treatment of IT instructions below, otherwise a // dbg_value followed by an IT will result in the IT instruction being // considered a scheduling hazard, which is wrong. It should be the actual // instruction preceding the dbg_value instruction(s), just like it is // when debug info is not present. if (MI->isDebugValue()) return false; // Terminators and labels can't be scheduled around. if (MI->isTerminator() || MI->isPosition()) return true; // Treat the start of the IT block as a scheduling boundary, but schedule // t2IT along with all instructions following it. // FIXME: This is a big hammer. But the alternative is to add all potential // true and anti dependencies to IT block instructions as implicit operands // to the t2IT instruction. The added compile time and complexity does not // seem worth it. MachineBasicBlock::const_iterator I = MI; // Make sure to skip any dbg_value instructions while (++I != MBB->end() && I->isDebugValue()) ; if (I != MBB->end() && I->getOpcode() == ARM::t2IT) return true; // Don't attempt to schedule around any instruction that defines // a stack-oriented pointer, as it's unlikely to be profitable. This // saves compile time, because it doesn't require every single // stack slot reference to depend on the instruction that does the // modification. // Calls don't actually change the stack pointer, even if they have imp-defs. // No ARM calling conventions change the stack pointer. (X86 calling // conventions sometimes do). if (!MI->isCall() && MI->definesRegister(ARM::SP)) return true; return false; } bool ARMBaseInstrInfo:: isProfitableToIfCvt(MachineBasicBlock &MBB, unsigned NumCycles, unsigned ExtraPredCycles, const BranchProbability &Probability) const { if (!NumCycles) return false; // If we are optimizing for size, see if the branch in the predecessor can be // lowered to cbn?z by the constant island lowering pass, and return false if // so. This results in a shorter instruction sequence. const Function *F = MBB.getParent()->getFunction(); if (F->hasFnAttribute(Attribute::OptimizeForSize) || F->hasFnAttribute(Attribute::MinSize)) { MachineBasicBlock *Pred = *MBB.pred_begin(); if (!Pred->empty()) { MachineInstr *LastMI = &*Pred->rbegin(); if (LastMI->getOpcode() == ARM::t2Bcc) { MachineBasicBlock::iterator CmpMI = LastMI; if (CmpMI != Pred->begin()) { --CmpMI; if (CmpMI->getOpcode() == ARM::tCMPi8 || CmpMI->getOpcode() == ARM::t2CMPri) { unsigned Reg = CmpMI->getOperand(0).getReg(); unsigned PredReg = 0; ARMCC::CondCodes P = getInstrPredicate(CmpMI, PredReg); if (P == ARMCC::AL && CmpMI->getOperand(1).getImm() == 0 && isARMLowRegister(Reg)) return false; } } } } } // Attempt to estimate the relative costs of predication versus branching. unsigned UnpredCost = Probability.getNumerator() * NumCycles; UnpredCost /= Probability.getDenominator(); UnpredCost += 1; // The branch itself UnpredCost += Subtarget.getMispredictionPenalty() / 10; return (NumCycles + ExtraPredCycles) <= UnpredCost; } bool ARMBaseInstrInfo:: isProfitableToIfCvt(MachineBasicBlock &TMBB, unsigned TCycles, unsigned TExtra, MachineBasicBlock &FMBB, unsigned FCycles, unsigned FExtra, const BranchProbability &Probability) const { if (!TCycles || !FCycles) return false; // Attempt to estimate the relative costs of predication versus branching. unsigned TUnpredCost = Probability.getNumerator() * TCycles; TUnpredCost /= Probability.getDenominator(); uint32_t Comp = Probability.getDenominator() - Probability.getNumerator(); unsigned FUnpredCost = Comp * FCycles; FUnpredCost /= Probability.getDenominator(); unsigned UnpredCost = TUnpredCost + FUnpredCost; UnpredCost += 1; // The branch itself UnpredCost += Subtarget.getMispredictionPenalty() / 10; return (TCycles + FCycles + TExtra + FExtra) <= UnpredCost; } bool ARMBaseInstrInfo::isProfitableToUnpredicate(MachineBasicBlock &TMBB, MachineBasicBlock &FMBB) const { // Reduce false anti-dependencies to let Swift's out-of-order execution // engine do its thing. return Subtarget.isSwift(); } /// getInstrPredicate - If instruction is predicated, returns its predicate /// condition, otherwise returns AL. It also returns the condition code /// register by reference. ARMCC::CondCodes llvm::getInstrPredicate(const MachineInstr *MI, unsigned &PredReg) { int PIdx = MI->findFirstPredOperandIdx(); if (PIdx == -1) { PredReg = 0; return ARMCC::AL; } PredReg = MI->getOperand(PIdx+1).getReg(); return (ARMCC::CondCodes)MI->getOperand(PIdx).getImm(); } unsigned llvm::getMatchingCondBranchOpcode(unsigned Opc) { if (Opc == ARM::B) return ARM::Bcc; if (Opc == ARM::tB) return ARM::tBcc; if (Opc == ARM::t2B) return ARM::t2Bcc; llvm_unreachable("Unknown unconditional branch opcode!"); } /// commuteInstruction - Handle commutable instructions. MachineInstr * ARMBaseInstrInfo::commuteInstruction(MachineInstr *MI, bool NewMI) const { switch (MI->getOpcode()) { case ARM::MOVCCr: case ARM::t2MOVCCr: { // MOVCC can be commuted by inverting the condition. unsigned PredReg = 0; ARMCC::CondCodes CC = getInstrPredicate(MI, PredReg); // MOVCC AL can't be inverted. Shouldn't happen. if (CC == ARMCC::AL || PredReg != ARM::CPSR) return nullptr; MI = TargetInstrInfo::commuteInstruction(MI, NewMI); if (!MI) return nullptr; // After swapping the MOVCC operands, also invert the condition. MI->getOperand(MI->findFirstPredOperandIdx()) .setImm(ARMCC::getOppositeCondition(CC)); return MI; } } return TargetInstrInfo::commuteInstruction(MI, NewMI); } /// Identify instructions that can be folded into a MOVCC instruction, and /// return the defining instruction. static MachineInstr *canFoldIntoMOVCC(unsigned Reg, const MachineRegisterInfo &MRI, const TargetInstrInfo *TII) { if (!TargetRegisterInfo::isVirtualRegister(Reg)) return nullptr; if (!MRI.hasOneNonDBGUse(Reg)) return nullptr; MachineInstr *MI = MRI.getVRegDef(Reg); if (!MI) return nullptr; // MI is folded into the MOVCC by predicating it. if (!MI->isPredicable()) return nullptr; // Check if MI has any non-dead defs or physreg uses. This also detects // predicated instructions which will be reading CPSR. for (unsigned i = 1, e = MI->getNumOperands(); i != e; ++i) { const MachineOperand &MO = MI->getOperand(i); // Reject frame index operands, PEI can't handle the predicated pseudos. if (MO.isFI() || MO.isCPI() || MO.isJTI()) return nullptr; if (!MO.isReg()) continue; // MI can't have any tied operands, that would conflict with predication. if (MO.isTied()) return nullptr; if (TargetRegisterInfo::isPhysicalRegister(MO.getReg())) return nullptr; if (MO.isDef() && !MO.isDead()) return nullptr; } bool DontMoveAcrossStores = true; if (!MI->isSafeToMove(/* AliasAnalysis = */ nullptr, DontMoveAcrossStores)) return nullptr; return MI; } bool ARMBaseInstrInfo::analyzeSelect(const MachineInstr *MI, SmallVectorImpl &Cond, unsigned &TrueOp, unsigned &FalseOp, bool &Optimizable) const { assert((MI->getOpcode() == ARM::MOVCCr || MI->getOpcode() == ARM::t2MOVCCr) && "Unknown select instruction"); // MOVCC operands: // 0: Def. // 1: True use. // 2: False use. // 3: Condition code. // 4: CPSR use. TrueOp = 1; FalseOp = 2; Cond.push_back(MI->getOperand(3)); Cond.push_back(MI->getOperand(4)); // We can always fold a def. Optimizable = true; return false; } MachineInstr * ARMBaseInstrInfo::optimizeSelect(MachineInstr *MI, SmallPtrSetImpl &SeenMIs, bool PreferFalse) const { assert((MI->getOpcode() == ARM::MOVCCr || MI->getOpcode() == ARM::t2MOVCCr) && "Unknown select instruction"); MachineRegisterInfo &MRI = MI->getParent()->getParent()->getRegInfo(); MachineInstr *DefMI = canFoldIntoMOVCC(MI->getOperand(2).getReg(), MRI, this); bool Invert = !DefMI; if (!DefMI) DefMI = canFoldIntoMOVCC(MI->getOperand(1).getReg(), MRI, this); if (!DefMI) return nullptr; // Find new register class to use. MachineOperand FalseReg = MI->getOperand(Invert ? 2 : 1); unsigned DestReg = MI->getOperand(0).getReg(); const TargetRegisterClass *PreviousClass = MRI.getRegClass(FalseReg.getReg()); if (!MRI.constrainRegClass(DestReg, PreviousClass)) return nullptr; // Create a new predicated version of DefMI. // Rfalse is the first use. MachineInstrBuilder NewMI = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(), DefMI->getDesc(), DestReg); // Copy all the DefMI operands, excluding its (null) predicate. const MCInstrDesc &DefDesc = DefMI->getDesc(); for (unsigned i = 1, e = DefDesc.getNumOperands(); i != e && !DefDesc.OpInfo[i].isPredicate(); ++i) NewMI.addOperand(DefMI->getOperand(i)); unsigned CondCode = MI->getOperand(3).getImm(); if (Invert) NewMI.addImm(ARMCC::getOppositeCondition(ARMCC::CondCodes(CondCode))); else NewMI.addImm(CondCode); NewMI.addOperand(MI->getOperand(4)); // DefMI is not the -S version that sets CPSR, so add an optional %noreg. if (NewMI->hasOptionalDef()) AddDefaultCC(NewMI); // The output register value when the predicate is false is an implicit // register operand tied to the first def. // The tie makes the register allocator ensure the FalseReg is allocated the // same register as operand 0. FalseReg.setImplicit(); NewMI.addOperand(FalseReg); NewMI->tieOperands(0, NewMI->getNumOperands() - 1); // Update SeenMIs set: register newly created MI and erase removed DefMI. SeenMIs.insert(NewMI); SeenMIs.erase(DefMI); // If MI is inside a loop, and DefMI is outside the loop, then kill flags on // DefMI would be invalid when tranferred inside the loop. Checking for a // loop is expensive, but at least remove kill flags if they are in different // BBs. if (DefMI->getParent() != MI->getParent()) NewMI->clearKillInfo(); // The caller will erase MI, but not DefMI. DefMI->eraseFromParent(); return NewMI; } /// Map pseudo instructions that imply an 'S' bit onto real opcodes. Whether the /// instruction is encoded with an 'S' bit is determined by the optional CPSR /// def operand. /// /// This will go away once we can teach tblgen how to set the optional CPSR def /// operand itself. struct AddSubFlagsOpcodePair { uint16_t PseudoOpc; uint16_t MachineOpc; }; static const AddSubFlagsOpcodePair AddSubFlagsOpcodeMap[] = { {ARM::ADDSri, ARM::ADDri}, {ARM::ADDSrr, ARM::ADDrr}, {ARM::ADDSrsi, ARM::ADDrsi}, {ARM::ADDSrsr, ARM::ADDrsr}, {ARM::SUBSri, ARM::SUBri}, {ARM::SUBSrr, ARM::SUBrr}, {ARM::SUBSrsi, ARM::SUBrsi}, {ARM::SUBSrsr, ARM::SUBrsr}, {ARM::RSBSri, ARM::RSBri}, {ARM::RSBSrsi, ARM::RSBrsi}, {ARM::RSBSrsr, ARM::RSBrsr}, {ARM::t2ADDSri, ARM::t2ADDri}, {ARM::t2ADDSrr, ARM::t2ADDrr}, {ARM::t2ADDSrs, ARM::t2ADDrs}, {ARM::t2SUBSri, ARM::t2SUBri}, {ARM::t2SUBSrr, ARM::t2SUBrr}, {ARM::t2SUBSrs, ARM::t2SUBrs}, {ARM::t2RSBSri, ARM::t2RSBri}, {ARM::t2RSBSrs, ARM::t2RSBrs}, }; unsigned llvm::convertAddSubFlagsOpcode(unsigned OldOpc) { for (unsigned i = 0, e = array_lengthof(AddSubFlagsOpcodeMap); i != e; ++i) if (OldOpc == AddSubFlagsOpcodeMap[i].PseudoOpc) return AddSubFlagsOpcodeMap[i].MachineOpc; return 0; } void llvm::emitARMRegPlusImmediate(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI, DebugLoc dl, unsigned DestReg, unsigned BaseReg, int NumBytes, ARMCC::CondCodes Pred, unsigned PredReg, const ARMBaseInstrInfo &TII, unsigned MIFlags) { if (NumBytes == 0 && DestReg != BaseReg) { BuildMI(MBB, MBBI, dl, TII.get(ARM::MOVr), DestReg) .addReg(BaseReg, RegState::Kill) .addImm((unsigned)Pred).addReg(PredReg).addReg(0) .setMIFlags(MIFlags); return; } bool isSub = NumBytes < 0; if (isSub) NumBytes = -NumBytes; while (NumBytes) { unsigned RotAmt = ARM_AM::getSOImmValRotate(NumBytes); unsigned ThisVal = NumBytes & ARM_AM::rotr32(0xFF, RotAmt); assert(ThisVal && "Didn't extract field correctly"); // We will handle these bits from offset, clear them. NumBytes &= ~ThisVal; assert(ARM_AM::getSOImmVal(ThisVal) != -1 && "Bit extraction didn't work?"); // Build the new ADD / SUB. unsigned Opc = isSub ? ARM::SUBri : ARM::ADDri; BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg) .addReg(BaseReg, RegState::Kill).addImm(ThisVal) .addImm((unsigned)Pred).addReg(PredReg).addReg(0) .setMIFlags(MIFlags); BaseReg = DestReg; } } static bool isAnySubRegLive(unsigned Reg, const TargetRegisterInfo *TRI, MachineInstr *MI) { for (MCSubRegIterator Subreg(Reg, TRI, /* IncludeSelf */ true); Subreg.isValid(); ++Subreg) if (MI->getParent()->computeRegisterLiveness(TRI, *Subreg, MI) != MachineBasicBlock::LQR_Dead) return true; return false; } bool llvm::tryFoldSPUpdateIntoPushPop(const ARMSubtarget &Subtarget, MachineFunction &MF, MachineInstr *MI, unsigned NumBytes) { // This optimisation potentially adds lots of load and store // micro-operations, it's only really a great benefit to code-size. if (!MF.getFunction()->hasFnAttribute(Attribute::MinSize)) return false; // If only one register is pushed/popped, LLVM can use an LDR/STR // instead. We can't modify those so make sure we're dealing with an // instruction we understand. bool IsPop = isPopOpcode(MI->getOpcode()); bool IsPush = isPushOpcode(MI->getOpcode()); if (!IsPush && !IsPop) return false; bool IsVFPPushPop = MI->getOpcode() == ARM::VSTMDDB_UPD || MI->getOpcode() == ARM::VLDMDIA_UPD; bool IsT1PushPop = MI->getOpcode() == ARM::tPUSH || MI->getOpcode() == ARM::tPOP || MI->getOpcode() == ARM::tPOP_RET; assert((IsT1PushPop || (MI->getOperand(0).getReg() == ARM::SP && MI->getOperand(1).getReg() == ARM::SP)) && "trying to fold sp update into non-sp-updating push/pop"); // The VFP push & pop act on D-registers, so we can only fold an adjustment // by a multiple of 8 bytes in correctly. Similarly rN is 4-bytes. Don't try // if this is violated. if (NumBytes % (IsVFPPushPop ? 8 : 4) != 0) return false; // ARM and Thumb2 push/pop insts have explicit "sp, sp" operands (+ // pred) so the list starts at 4. Thumb1 starts after the predicate. int RegListIdx = IsT1PushPop ? 2 : 4; // Calculate the space we'll need in terms of registers. unsigned FirstReg = MI->getOperand(RegListIdx).getReg(); unsigned RD0Reg, RegsNeeded; if (IsVFPPushPop) { RD0Reg = ARM::D0; RegsNeeded = NumBytes / 8; } else { RD0Reg = ARM::R0; RegsNeeded = NumBytes / 4; } // We're going to have to strip all list operands off before // re-adding them since the order matters, so save the existing ones // for later. SmallVector RegList; for (int i = MI->getNumOperands() - 1; i >= RegListIdx; --i) RegList.push_back(MI->getOperand(i)); const TargetRegisterInfo *TRI = MF.getRegInfo().getTargetRegisterInfo(); const MCPhysReg *CSRegs = TRI->getCalleeSavedRegs(&MF); // Now try to find enough space in the reglist to allocate NumBytes. for (unsigned CurReg = FirstReg - 1; CurReg >= RD0Reg && RegsNeeded; --CurReg) { if (!IsPop) { // Pushing any register is completely harmless, mark the // register involved as undef since we don't care about it in // the slightest. RegList.push_back(MachineOperand::CreateReg(CurReg, false, false, false, false, true)); --RegsNeeded; continue; } // However, we can only pop an extra register if it's not live. For // registers live within the function we might clobber a return value // register; the other way a register can be live here is if it's // callee-saved. // TODO: Currently, computeRegisterLiveness() does not report "live" if a // sub reg is live. When computeRegisterLiveness() works for sub reg, it // can replace isAnySubRegLive(). if (isCalleeSavedRegister(CurReg, CSRegs) || isAnySubRegLive(CurReg, TRI, MI)) { // VFP pops don't allow holes in the register list, so any skip is fatal // for our transformation. GPR pops do, so we should just keep looking. if (IsVFPPushPop) return false; else continue; } // Mark the unimportant registers as in the POP. RegList.push_back(MachineOperand::CreateReg(CurReg, true, false, false, true)); --RegsNeeded; } if (RegsNeeded > 0) return false; // Finally we know we can profitably perform the optimisation so go // ahead: strip all existing registers off and add them back again // in the right order. for (int i = MI->getNumOperands() - 1; i >= RegListIdx; --i) MI->RemoveOperand(i); // Add the complete list back in. MachineInstrBuilder MIB(MF, &*MI); for (int i = RegList.size() - 1; i >= 0; --i) MIB.addOperand(RegList[i]); return true; } bool llvm::rewriteARMFrameIndex(MachineInstr &MI, unsigned FrameRegIdx, unsigned FrameReg, int &Offset, const ARMBaseInstrInfo &TII) { unsigned Opcode = MI.getOpcode(); const MCInstrDesc &Desc = MI.getDesc(); unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask); bool isSub = false; // Memory operands in inline assembly always use AddrMode2. if (Opcode == ARM::INLINEASM) AddrMode = ARMII::AddrMode2; if (Opcode == ARM::ADDri) { Offset += MI.getOperand(FrameRegIdx+1).getImm(); if (Offset == 0) { // Turn it into a move. MI.setDesc(TII.get(ARM::MOVr)); MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); MI.RemoveOperand(FrameRegIdx+1); Offset = 0; return true; } else if (Offset < 0) { Offset = -Offset; isSub = true; MI.setDesc(TII.get(ARM::SUBri)); } // Common case: small offset, fits into instruction. if (ARM_AM::getSOImmVal(Offset) != -1) { // Replace the FrameIndex with sp / fp MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset); Offset = 0; return true; } // Otherwise, pull as much of the immedidate into this ADDri/SUBri // as possible. unsigned RotAmt = ARM_AM::getSOImmValRotate(Offset); unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xFF, RotAmt); // We will handle these bits from offset, clear them. Offset &= ~ThisImmVal; // Get the properly encoded SOImmVal field. assert(ARM_AM::getSOImmVal(ThisImmVal) != -1 && "Bit extraction didn't work?"); MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal); } else { unsigned ImmIdx = 0; int InstrOffs = 0; unsigned NumBits = 0; unsigned Scale = 1; switch (AddrMode) { case ARMII::AddrMode_i12: { ImmIdx = FrameRegIdx + 1; InstrOffs = MI.getOperand(ImmIdx).getImm(); NumBits = 12; break; } case ARMII::AddrMode2: { ImmIdx = FrameRegIdx+2; InstrOffs = ARM_AM::getAM2Offset(MI.getOperand(ImmIdx).getImm()); if (ARM_AM::getAM2Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) InstrOffs *= -1; NumBits = 12; break; } case ARMII::AddrMode3: { ImmIdx = FrameRegIdx+2; InstrOffs = ARM_AM::getAM3Offset(MI.getOperand(ImmIdx).getImm()); if (ARM_AM::getAM3Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) InstrOffs *= -1; NumBits = 8; break; } case ARMII::AddrMode4: case ARMII::AddrMode6: // Can't fold any offset even if it's zero. return false; case ARMII::AddrMode5: { ImmIdx = FrameRegIdx+1; InstrOffs = ARM_AM::getAM5Offset(MI.getOperand(ImmIdx).getImm()); if (ARM_AM::getAM5Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) InstrOffs *= -1; NumBits = 8; Scale = 4; break; } default: llvm_unreachable("Unsupported addressing mode!"); } Offset += InstrOffs * Scale; assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!"); if (Offset < 0) { Offset = -Offset; isSub = true; } // Attempt to fold address comp. if opcode has offset bits if (NumBits > 0) { // Common case: small offset, fits into instruction. MachineOperand &ImmOp = MI.getOperand(ImmIdx); int ImmedOffset = Offset / Scale; unsigned Mask = (1 << NumBits) - 1; if ((unsigned)Offset <= Mask * Scale) { // Replace the FrameIndex with sp MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); // FIXME: When addrmode2 goes away, this will simplify (like the // T2 version), as the LDR.i12 versions don't need the encoding // tricks for the offset value. if (isSub) { if (AddrMode == ARMII::AddrMode_i12) ImmedOffset = -ImmedOffset; else ImmedOffset |= 1 << NumBits; } ImmOp.ChangeToImmediate(ImmedOffset); Offset = 0; return true; } // Otherwise, it didn't fit. Pull in what we can to simplify the immed. ImmedOffset = ImmedOffset & Mask; if (isSub) { if (AddrMode == ARMII::AddrMode_i12) ImmedOffset = -ImmedOffset; else ImmedOffset |= 1 << NumBits; } ImmOp.ChangeToImmediate(ImmedOffset); Offset &= ~(Mask*Scale); } } Offset = (isSub) ? -Offset : Offset; return Offset == 0; } /// analyzeCompare - For a comparison instruction, return the source registers /// in SrcReg and SrcReg2 if having two register operands, and the value it /// compares against in CmpValue. Return true if the comparison instruction /// can be analyzed. bool ARMBaseInstrInfo:: analyzeCompare(const MachineInstr *MI, unsigned &SrcReg, unsigned &SrcReg2, int &CmpMask, int &CmpValue) const { switch (MI->getOpcode()) { default: break; case ARM::CMPri: case ARM::t2CMPri: SrcReg = MI->getOperand(0).getReg(); SrcReg2 = 0; CmpMask = ~0; CmpValue = MI->getOperand(1).getImm(); return true; case ARM::CMPrr: case ARM::t2CMPrr: SrcReg = MI->getOperand(0).getReg(); SrcReg2 = MI->getOperand(1).getReg(); CmpMask = ~0; CmpValue = 0; return true; case ARM::TSTri: case ARM::t2TSTri: SrcReg = MI->getOperand(0).getReg(); SrcReg2 = 0; CmpMask = MI->getOperand(1).getImm(); CmpValue = 0; return true; } return false; } /// isSuitableForMask - Identify a suitable 'and' instruction that /// operates on the given source register and applies the same mask /// as a 'tst' instruction. Provide a limited look-through for copies. /// When successful, MI will hold the found instruction. static bool isSuitableForMask(MachineInstr *&MI, unsigned SrcReg, int CmpMask, bool CommonUse) { switch (MI->getOpcode()) { case ARM::ANDri: case ARM::t2ANDri: if (CmpMask != MI->getOperand(2).getImm()) return false; if (SrcReg == MI->getOperand(CommonUse ? 1 : 0).getReg()) return true; break; } return false; } /// getSwappedCondition - assume the flags are set by MI(a,b), return /// the condition code if we modify the instructions such that flags are /// set by MI(b,a). inline static ARMCC::CondCodes getSwappedCondition(ARMCC::CondCodes CC) { switch (CC) { default: return ARMCC::AL; case ARMCC::EQ: return ARMCC::EQ; case ARMCC::NE: return ARMCC::NE; case ARMCC::HS: return ARMCC::LS; case ARMCC::LO: return ARMCC::HI; case ARMCC::HI: return ARMCC::LO; case ARMCC::LS: return ARMCC::HS; case ARMCC::GE: return ARMCC::LE; case ARMCC::LT: return ARMCC::GT; case ARMCC::GT: return ARMCC::LT; case ARMCC::LE: return ARMCC::GE; } } /// isRedundantFlagInstr - check whether the first instruction, whose only /// purpose is to update flags, can be made redundant. /// CMPrr can be made redundant by SUBrr if the operands are the same. /// CMPri can be made redundant by SUBri if the operands are the same. /// This function can be extended later on. inline static bool isRedundantFlagInstr(MachineInstr *CmpI, unsigned SrcReg, unsigned SrcReg2, int ImmValue, MachineInstr *OI) { if ((CmpI->getOpcode() == ARM::CMPrr || CmpI->getOpcode() == ARM::t2CMPrr) && (OI->getOpcode() == ARM::SUBrr || OI->getOpcode() == ARM::t2SUBrr) && ((OI->getOperand(1).getReg() == SrcReg && OI->getOperand(2).getReg() == SrcReg2) || (OI->getOperand(1).getReg() == SrcReg2 && OI->getOperand(2).getReg() == SrcReg))) return true; if ((CmpI->getOpcode() == ARM::CMPri || CmpI->getOpcode() == ARM::t2CMPri) && (OI->getOpcode() == ARM::SUBri || OI->getOpcode() == ARM::t2SUBri) && OI->getOperand(1).getReg() == SrcReg && OI->getOperand(2).getImm() == ImmValue) return true; return false; } /// optimizeCompareInstr - Convert the instruction supplying the argument to the /// comparison into one that sets the zero bit in the flags register; /// Remove a redundant Compare instruction if an earlier instruction can set the /// flags in the same way as Compare. /// E.g. SUBrr(r1,r2) and CMPrr(r1,r2). We also handle the case where two /// operands are swapped: SUBrr(r1,r2) and CMPrr(r2,r1), by updating the /// condition code of instructions which use the flags. bool ARMBaseInstrInfo:: optimizeCompareInstr(MachineInstr *CmpInstr, unsigned SrcReg, unsigned SrcReg2, int CmpMask, int CmpValue, const MachineRegisterInfo *MRI) const { // Get the unique definition of SrcReg. MachineInstr *MI = MRI->getUniqueVRegDef(SrcReg); if (!MI) return false; // Masked compares sometimes use the same register as the corresponding 'and'. if (CmpMask != ~0) { if (!isSuitableForMask(MI, SrcReg, CmpMask, false) || isPredicated(MI)) { MI = nullptr; for (MachineRegisterInfo::use_instr_iterator UI = MRI->use_instr_begin(SrcReg), UE = MRI->use_instr_end(); UI != UE; ++UI) { if (UI->getParent() != CmpInstr->getParent()) continue; MachineInstr *PotentialAND = &*UI; if (!isSuitableForMask(PotentialAND, SrcReg, CmpMask, true) || isPredicated(PotentialAND)) continue; MI = PotentialAND; break; } if (!MI) return false; } } // Get ready to iterate backward from CmpInstr. MachineBasicBlock::iterator I = CmpInstr, E = MI, B = CmpInstr->getParent()->begin(); // Early exit if CmpInstr is at the beginning of the BB. if (I == B) return false; // There are two possible candidates which can be changed to set CPSR: // One is MI, the other is a SUB instruction. // For CMPrr(r1,r2), we are looking for SUB(r1,r2) or SUB(r2,r1). // For CMPri(r1, CmpValue), we are looking for SUBri(r1, CmpValue). MachineInstr *Sub = nullptr; if (SrcReg2 != 0) // MI is not a candidate for CMPrr. MI = nullptr; else if (MI->getParent() != CmpInstr->getParent() || CmpValue != 0) { // Conservatively refuse to convert an instruction which isn't in the same // BB as the comparison. // For CMPri w/ CmpValue != 0, a Sub may still be a candidate. // Thus we cannot return here. if (CmpInstr->getOpcode() == ARM::CMPri || CmpInstr->getOpcode() == ARM::t2CMPri) MI = nullptr; else return false; } // Check that CPSR isn't set between the comparison instruction and the one we // want to change. At the same time, search for Sub. const TargetRegisterInfo *TRI = &getRegisterInfo(); --I; for (; I != E; --I) { const MachineInstr &Instr = *I; if (Instr.modifiesRegister(ARM::CPSR, TRI) || Instr.readsRegister(ARM::CPSR, TRI)) // This instruction modifies or uses CPSR after the one we want to // change. We can't do this transformation. return false; // Check whether CmpInstr can be made redundant by the current instruction. if (isRedundantFlagInstr(CmpInstr, SrcReg, SrcReg2, CmpValue, &*I)) { Sub = &*I; break; } if (I == B) // The 'and' is below the comparison instruction. return false; } // Return false if no candidates exist. if (!MI && !Sub) return false; // The single candidate is called MI. if (!MI) MI = Sub; // We can't use a predicated instruction - it doesn't always write the flags. if (isPredicated(MI)) return false; switch (MI->getOpcode()) { default: break; case ARM::RSBrr: case ARM::RSBri: case ARM::RSCrr: case ARM::RSCri: case ARM::ADDrr: case ARM::ADDri: case ARM::ADCrr: case ARM::ADCri: case ARM::SUBrr: case ARM::SUBri: case ARM::SBCrr: case ARM::SBCri: case ARM::t2RSBri: case ARM::t2ADDrr: case ARM::t2ADDri: case ARM::t2ADCrr: case ARM::t2ADCri: case ARM::t2SUBrr: case ARM::t2SUBri: case ARM::t2SBCrr: case ARM::t2SBCri: case ARM::ANDrr: case ARM::ANDri: case ARM::t2ANDrr: case ARM::t2ANDri: case ARM::ORRrr: case ARM::ORRri: case ARM::t2ORRrr: case ARM::t2ORRri: case ARM::EORrr: case ARM::EORri: case ARM::t2EORrr: case ARM::t2EORri: { // Scan forward for the use of CPSR // When checking against MI: if it's a conditional code that requires // checking of the V bit or C bit, then this is not safe to do. // It is safe to remove CmpInstr if CPSR is redefined or killed. // If we are done with the basic block, we need to check whether CPSR is // live-out. SmallVector, 4> OperandsToUpdate; bool isSafe = false; I = CmpInstr; E = CmpInstr->getParent()->end(); while (!isSafe && ++I != E) { const MachineInstr &Instr = *I; for (unsigned IO = 0, EO = Instr.getNumOperands(); !isSafe && IO != EO; ++IO) { const MachineOperand &MO = Instr.getOperand(IO); if (MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) { isSafe = true; break; } if (!MO.isReg() || MO.getReg() != ARM::CPSR) continue; if (MO.isDef()) { isSafe = true; break; } // Condition code is after the operand before CPSR except for VSELs. ARMCC::CondCodes CC; bool IsInstrVSel = true; switch (Instr.getOpcode()) { default: IsInstrVSel = false; CC = (ARMCC::CondCodes)Instr.getOperand(IO - 1).getImm(); break; case ARM::VSELEQD: case ARM::VSELEQS: CC = ARMCC::EQ; break; case ARM::VSELGTD: case ARM::VSELGTS: CC = ARMCC::GT; break; case ARM::VSELGED: case ARM::VSELGES: CC = ARMCC::GE; break; case ARM::VSELVSS: case ARM::VSELVSD: CC = ARMCC::VS; break; } if (Sub) { ARMCC::CondCodes NewCC = getSwappedCondition(CC); if (NewCC == ARMCC::AL) return false; // If we have SUB(r1, r2) and CMP(r2, r1), the condition code based // on CMP needs to be updated to be based on SUB. // Push the condition code operands to OperandsToUpdate. // If it is safe to remove CmpInstr, the condition code of these // operands will be modified. if (SrcReg2 != 0 && Sub->getOperand(1).getReg() == SrcReg2 && Sub->getOperand(2).getReg() == SrcReg) { // VSel doesn't support condition code update. if (IsInstrVSel) return false; OperandsToUpdate.push_back( std::make_pair(&((*I).getOperand(IO - 1)), NewCC)); } } else { // No Sub, so this is x = y, z; cmp x, 0. switch (CC) { case ARMCC::EQ: // Z case ARMCC::NE: // Z case ARMCC::MI: // N case ARMCC::PL: // N case ARMCC::AL: // none // CPSR can be used multiple times, we should continue. break; case ARMCC::HS: // C case ARMCC::LO: // C case ARMCC::VS: // V case ARMCC::VC: // V case ARMCC::HI: // C Z case ARMCC::LS: // C Z case ARMCC::GE: // N V case ARMCC::LT: // N V case ARMCC::GT: // Z N V case ARMCC::LE: // Z N V // The instruction uses the V bit or C bit which is not safe. return false; } } } } // If CPSR is not killed nor re-defined, we should check whether it is // live-out. If it is live-out, do not optimize. if (!isSafe) { MachineBasicBlock *MBB = CmpInstr->getParent(); for (MachineBasicBlock::succ_iterator SI = MBB->succ_begin(), SE = MBB->succ_end(); SI != SE; ++SI) if ((*SI)->isLiveIn(ARM::CPSR)) return false; } // Toggle the optional operand to CPSR. MI->getOperand(5).setReg(ARM::CPSR); MI->getOperand(5).setIsDef(true); assert(!isPredicated(MI) && "Can't use flags from predicated instruction"); CmpInstr->eraseFromParent(); // Modify the condition code of operands in OperandsToUpdate. // Since we have SUB(r1, r2) and CMP(r2, r1), the condition code needs to // be changed from r2 > r1 to r1 < r2, from r2 < r1 to r1 > r2, etc. for (unsigned i = 0, e = OperandsToUpdate.size(); i < e; i++) OperandsToUpdate[i].first->setImm(OperandsToUpdate[i].second); return true; } } return false; } bool ARMBaseInstrInfo::FoldImmediate(MachineInstr *UseMI, MachineInstr *DefMI, unsigned Reg, MachineRegisterInfo *MRI) const { // Fold large immediates into add, sub, or, xor. unsigned DefOpc = DefMI->getOpcode(); if (DefOpc != ARM::t2MOVi32imm && DefOpc != ARM::MOVi32imm) return false; if (!DefMI->getOperand(1).isImm()) // Could be t2MOVi32imm return false; if (!MRI->hasOneNonDBGUse(Reg)) return false; const MCInstrDesc &DefMCID = DefMI->getDesc(); if (DefMCID.hasOptionalDef()) { unsigned NumOps = DefMCID.getNumOperands(); const MachineOperand &MO = DefMI->getOperand(NumOps-1); if (MO.getReg() == ARM::CPSR && !MO.isDead()) // If DefMI defines CPSR and it is not dead, it's obviously not safe // to delete DefMI. return false; } const MCInstrDesc &UseMCID = UseMI->getDesc(); if (UseMCID.hasOptionalDef()) { unsigned NumOps = UseMCID.getNumOperands(); if (UseMI->getOperand(NumOps-1).getReg() == ARM::CPSR) // If the instruction sets the flag, do not attempt this optimization // since it may change the semantics of the code. return false; } unsigned UseOpc = UseMI->getOpcode(); unsigned NewUseOpc = 0; uint32_t ImmVal = (uint32_t)DefMI->getOperand(1).getImm(); uint32_t SOImmValV1 = 0, SOImmValV2 = 0; bool Commute = false; switch (UseOpc) { default: return false; case ARM::SUBrr: case ARM::ADDrr: case ARM::ORRrr: case ARM::EORrr: case ARM::t2SUBrr: case ARM::t2ADDrr: case ARM::t2ORRrr: case ARM::t2EORrr: { Commute = UseMI->getOperand(2).getReg() != Reg; switch (UseOpc) { default: break; case ARM::SUBrr: { if (Commute) return false; ImmVal = -ImmVal; NewUseOpc = ARM::SUBri; // Fallthrough } case ARM::ADDrr: case ARM::ORRrr: case ARM::EORrr: { if (!ARM_AM::isSOImmTwoPartVal(ImmVal)) return false; SOImmValV1 = (uint32_t)ARM_AM::getSOImmTwoPartFirst(ImmVal); SOImmValV2 = (uint32_t)ARM_AM::getSOImmTwoPartSecond(ImmVal); switch (UseOpc) { default: break; case ARM::ADDrr: NewUseOpc = ARM::ADDri; break; case ARM::ORRrr: NewUseOpc = ARM::ORRri; break; case ARM::EORrr: NewUseOpc = ARM::EORri; break; } break; } case ARM::t2SUBrr: { if (Commute) return false; ImmVal = -ImmVal; NewUseOpc = ARM::t2SUBri; // Fallthrough } case ARM::t2ADDrr: case ARM::t2ORRrr: case ARM::t2EORrr: { if (!ARM_AM::isT2SOImmTwoPartVal(ImmVal)) return false; SOImmValV1 = (uint32_t)ARM_AM::getT2SOImmTwoPartFirst(ImmVal); SOImmValV2 = (uint32_t)ARM_AM::getT2SOImmTwoPartSecond(ImmVal); switch (UseOpc) { default: break; case ARM::t2ADDrr: NewUseOpc = ARM::t2ADDri; break; case ARM::t2ORRrr: NewUseOpc = ARM::t2ORRri; break; case ARM::t2EORrr: NewUseOpc = ARM::t2EORri; break; } break; } } } } unsigned OpIdx = Commute ? 2 : 1; unsigned Reg1 = UseMI->getOperand(OpIdx).getReg(); bool isKill = UseMI->getOperand(OpIdx).isKill(); unsigned NewReg = MRI->createVirtualRegister(MRI->getRegClass(Reg)); AddDefaultCC(AddDefaultPred(BuildMI(*UseMI->getParent(), UseMI, UseMI->getDebugLoc(), get(NewUseOpc), NewReg) .addReg(Reg1, getKillRegState(isKill)) .addImm(SOImmValV1))); UseMI->setDesc(get(NewUseOpc)); UseMI->getOperand(1).setReg(NewReg); UseMI->getOperand(1).setIsKill(); UseMI->getOperand(2).ChangeToImmediate(SOImmValV2); DefMI->eraseFromParent(); return true; } static unsigned getNumMicroOpsSwiftLdSt(const InstrItineraryData *ItinData, const MachineInstr *MI) { switch (MI->getOpcode()) { default: { const MCInstrDesc &Desc = MI->getDesc(); int UOps = ItinData->getNumMicroOps(Desc.getSchedClass()); assert(UOps >= 0 && "bad # UOps"); return UOps; } case ARM::LDRrs: case ARM::LDRBrs: case ARM::STRrs: case ARM::STRBrs: { unsigned ShOpVal = MI->getOperand(3).getImm(); bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); if (!isSub && (ShImm == 0 || ((ShImm == 1 || ShImm == 2 || ShImm == 3) && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) return 1; return 2; } case ARM::LDRH: case ARM::STRH: { if (!MI->getOperand(2).getReg()) return 1; unsigned ShOpVal = MI->getOperand(3).getImm(); bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); if (!isSub && (ShImm == 0 || ((ShImm == 1 || ShImm == 2 || ShImm == 3) && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) return 1; return 2; } case ARM::LDRSB: case ARM::LDRSH: return (ARM_AM::getAM3Op(MI->getOperand(3).getImm()) == ARM_AM::sub) ? 3:2; case ARM::LDRSB_POST: case ARM::LDRSH_POST: { unsigned Rt = MI->getOperand(0).getReg(); unsigned Rm = MI->getOperand(3).getReg(); return (Rt == Rm) ? 4 : 3; } case ARM::LDR_PRE_REG: case ARM::LDRB_PRE_REG: { unsigned Rt = MI->getOperand(0).getReg(); unsigned Rm = MI->getOperand(3).getReg(); if (Rt == Rm) return 3; unsigned ShOpVal = MI->getOperand(4).getImm(); bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); if (!isSub && (ShImm == 0 || ((ShImm == 1 || ShImm == 2 || ShImm == 3) && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) return 2; return 3; } case ARM::STR_PRE_REG: case ARM::STRB_PRE_REG: { unsigned ShOpVal = MI->getOperand(4).getImm(); bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); if (!isSub && (ShImm == 0 || ((ShImm == 1 || ShImm == 2 || ShImm == 3) && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) return 2; return 3; } case ARM::LDRH_PRE: case ARM::STRH_PRE: { unsigned Rt = MI->getOperand(0).getReg(); unsigned Rm = MI->getOperand(3).getReg(); if (!Rm) return 2; if (Rt == Rm) return 3; return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ? 3 : 2; } case ARM::LDR_POST_REG: case ARM::LDRB_POST_REG: case ARM::LDRH_POST: { unsigned Rt = MI->getOperand(0).getReg(); unsigned Rm = MI->getOperand(3).getReg(); return (Rt == Rm) ? 3 : 2; } case ARM::LDR_PRE_IMM: case ARM::LDRB_PRE_IMM: case ARM::LDR_POST_IMM: case ARM::LDRB_POST_IMM: case ARM::STRB_POST_IMM: case ARM::STRB_POST_REG: case ARM::STRB_PRE_IMM: case ARM::STRH_POST: case ARM::STR_POST_IMM: case ARM::STR_POST_REG: case ARM::STR_PRE_IMM: return 2; case ARM::LDRSB_PRE: case ARM::LDRSH_PRE: { unsigned Rm = MI->getOperand(3).getReg(); if (Rm == 0) return 3; unsigned Rt = MI->getOperand(0).getReg(); if (Rt == Rm) return 4; unsigned ShOpVal = MI->getOperand(4).getImm(); bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); if (!isSub && (ShImm == 0 || ((ShImm == 1 || ShImm == 2 || ShImm == 3) && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) return 3; return 4; } case ARM::LDRD: { unsigned Rt = MI->getOperand(0).getReg(); unsigned Rn = MI->getOperand(2).getReg(); unsigned Rm = MI->getOperand(3).getReg(); if (Rm) return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ?4:3; return (Rt == Rn) ? 3 : 2; } case ARM::STRD: { unsigned Rm = MI->getOperand(3).getReg(); if (Rm) return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ?4:3; return 2; } case ARM::LDRD_POST: case ARM::t2LDRD_POST: return 3; case ARM::STRD_POST: case ARM::t2STRD_POST: return 4; case ARM::LDRD_PRE: { unsigned Rt = MI->getOperand(0).getReg(); unsigned Rn = MI->getOperand(3).getReg(); unsigned Rm = MI->getOperand(4).getReg(); if (Rm) return (ARM_AM::getAM3Op(MI->getOperand(5).getImm()) == ARM_AM::sub) ?5:4; return (Rt == Rn) ? 4 : 3; } case ARM::t2LDRD_PRE: { unsigned Rt = MI->getOperand(0).getReg(); unsigned Rn = MI->getOperand(3).getReg(); return (Rt == Rn) ? 4 : 3; } case ARM::STRD_PRE: { unsigned Rm = MI->getOperand(4).getReg(); if (Rm) return (ARM_AM::getAM3Op(MI->getOperand(5).getImm()) == ARM_AM::sub) ?5:4; return 3; } case ARM::t2STRD_PRE: return 3; case ARM::t2LDR_POST: case ARM::t2LDRB_POST: case ARM::t2LDRB_PRE: case ARM::t2LDRSBi12: case ARM::t2LDRSBi8: case ARM::t2LDRSBpci: case ARM::t2LDRSBs: case ARM::t2LDRH_POST: case ARM::t2LDRH_PRE: case ARM::t2LDRSBT: case ARM::t2LDRSB_POST: case ARM::t2LDRSB_PRE: case ARM::t2LDRSH_POST: case ARM::t2LDRSH_PRE: case ARM::t2LDRSHi12: case ARM::t2LDRSHi8: case ARM::t2LDRSHpci: case ARM::t2LDRSHs: return 2; case ARM::t2LDRDi8: { unsigned Rt = MI->getOperand(0).getReg(); unsigned Rn = MI->getOperand(2).getReg(); return (Rt == Rn) ? 3 : 2; } case ARM::t2STRB_POST: case ARM::t2STRB_PRE: case ARM::t2STRBs: case ARM::t2STRDi8: case ARM::t2STRH_POST: case ARM::t2STRH_PRE: case ARM::t2STRHs: case ARM::t2STR_POST: case ARM::t2STR_PRE: case ARM::t2STRs: return 2; } } // Return the number of 32-bit words loaded by LDM or stored by STM. If this // can't be easily determined return 0 (missing MachineMemOperand). // // FIXME: The current MachineInstr design does not support relying on machine // mem operands to determine the width of a memory access. Instead, we expect // the target to provide this information based on the instruction opcode and // operands. However, using MachineMemOperand is the best solution now for // two reasons: // // 1) getNumMicroOps tries to infer LDM memory width from the total number of MI // operands. This is much more dangerous than using the MachineMemOperand // sizes because CodeGen passes can insert/remove optional machine operands. In // fact, it's totally incorrect for preRA passes and appears to be wrong for // postRA passes as well. // // 2) getNumLDMAddresses is only used by the scheduling machine model and any // machine model that calls this should handle the unknown (zero size) case. // // Long term, we should require a target hook that verifies MachineMemOperand // sizes during MC lowering. That target hook should be local to MC lowering // because we can't ensure that it is aware of other MI forms. Doing this will // ensure that MachineMemOperands are correctly propagated through all passes. unsigned ARMBaseInstrInfo::getNumLDMAddresses(const MachineInstr *MI) const { unsigned Size = 0; for (MachineInstr::mmo_iterator I = MI->memoperands_begin(), E = MI->memoperands_end(); I != E; ++I) { Size += (*I)->getSize(); } return Size / 4; } unsigned ARMBaseInstrInfo::getNumMicroOps(const InstrItineraryData *ItinData, const MachineInstr *MI) const { if (!ItinData || ItinData->isEmpty()) return 1; const MCInstrDesc &Desc = MI->getDesc(); unsigned Class = Desc.getSchedClass(); int ItinUOps = ItinData->getNumMicroOps(Class); if (ItinUOps >= 0) { if (Subtarget.isSwift() && (Desc.mayLoad() || Desc.mayStore())) return getNumMicroOpsSwiftLdSt(ItinData, MI); return ItinUOps; } unsigned Opc = MI->getOpcode(); switch (Opc) { default: llvm_unreachable("Unexpected multi-uops instruction!"); case ARM::VLDMQIA: case ARM::VSTMQIA: return 2; // The number of uOps for load / store multiple are determined by the number // registers. // // On Cortex-A8, each pair of register loads / stores can be scheduled on the // same cycle. The scheduling for the first load / store must be done // separately by assuming the address is not 64-bit aligned. // // On Cortex-A9, the formula is simply (#reg / 2) + (#reg % 2). If the address // is not 64-bit aligned, then AGU would take an extra cycle. For VFP / NEON // load / store multiple, the formula is (#reg / 2) + (#reg % 2) + 1. case ARM::VLDMDIA: case ARM::VLDMDIA_UPD: case ARM::VLDMDDB_UPD: case ARM::VLDMSIA: case ARM::VLDMSIA_UPD: case ARM::VLDMSDB_UPD: case ARM::VSTMDIA: case ARM::VSTMDIA_UPD: case ARM::VSTMDDB_UPD: case ARM::VSTMSIA: case ARM::VSTMSIA_UPD: case ARM::VSTMSDB_UPD: { unsigned NumRegs = MI->getNumOperands() - Desc.getNumOperands(); return (NumRegs / 2) + (NumRegs % 2) + 1; } case ARM::LDMIA_RET: case ARM::LDMIA: case ARM::LDMDA: case ARM::LDMDB: case ARM::LDMIB: case ARM::LDMIA_UPD: case ARM::LDMDA_UPD: case ARM::LDMDB_UPD: case ARM::LDMIB_UPD: case ARM::STMIA: case ARM::STMDA: case ARM::STMDB: case ARM::STMIB: case ARM::STMIA_UPD: case ARM::STMDA_UPD: case ARM::STMDB_UPD: case ARM::STMIB_UPD: case ARM::tLDMIA: case ARM::tLDMIA_UPD: case ARM::tSTMIA_UPD: case ARM::tPOP_RET: case ARM::tPOP: case ARM::tPUSH: case ARM::t2LDMIA_RET: case ARM::t2LDMIA: case ARM::t2LDMDB: case ARM::t2LDMIA_UPD: case ARM::t2LDMDB_UPD: case ARM::t2STMIA: case ARM::t2STMDB: case ARM::t2STMIA_UPD: case ARM::t2STMDB_UPD: { unsigned NumRegs = MI->getNumOperands() - Desc.getNumOperands() + 1; if (Subtarget.isSwift()) { int UOps = 1 + NumRegs; // One for address computation, one for each ld / st. switch (Opc) { default: break; case ARM::VLDMDIA_UPD: case ARM::VLDMDDB_UPD: case ARM::VLDMSIA_UPD: case ARM::VLDMSDB_UPD: case ARM::VSTMDIA_UPD: case ARM::VSTMDDB_UPD: case ARM::VSTMSIA_UPD: case ARM::VSTMSDB_UPD: case ARM::LDMIA_UPD: case ARM::LDMDA_UPD: case ARM::LDMDB_UPD: case ARM::LDMIB_UPD: case ARM::STMIA_UPD: case ARM::STMDA_UPD: case ARM::STMDB_UPD: case ARM::STMIB_UPD: case ARM::tLDMIA_UPD: case ARM::tSTMIA_UPD: case ARM::t2LDMIA_UPD: case ARM::t2LDMDB_UPD: case ARM::t2STMIA_UPD: case ARM::t2STMDB_UPD: ++UOps; // One for base register writeback. break; case ARM::LDMIA_RET: case ARM::tPOP_RET: case ARM::t2LDMIA_RET: UOps += 2; // One for base reg wb, one for write to pc. break; } return UOps; } else if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { if (NumRegs < 4) return 2; // 4 registers would be issued: 2, 2. // 5 registers would be issued: 2, 2, 1. int A8UOps = (NumRegs / 2); if (NumRegs % 2) ++A8UOps; return A8UOps; } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { int A9UOps = (NumRegs / 2); // If there are odd number of registers or if it's not 64-bit aligned, // then it takes an extra AGU (Address Generation Unit) cycle. if ((NumRegs % 2) || !MI->hasOneMemOperand() || (*MI->memoperands_begin())->getAlignment() < 8) ++A9UOps; return A9UOps; } else { // Assume the worst. return NumRegs; } } } } int ARMBaseInstrInfo::getVLDMDefCycle(const InstrItineraryData *ItinData, const MCInstrDesc &DefMCID, unsigned DefClass, unsigned DefIdx, unsigned DefAlign) const { int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1; if (RegNo <= 0) // Def is the address writeback. return ItinData->getOperandCycle(DefClass, DefIdx); int DefCycle; if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { // (regno / 2) + (regno % 2) + 1 DefCycle = RegNo / 2 + 1; if (RegNo % 2) ++DefCycle; } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { DefCycle = RegNo; bool isSLoad = false; switch (DefMCID.getOpcode()) { default: break; case ARM::VLDMSIA: case ARM::VLDMSIA_UPD: case ARM::VLDMSDB_UPD: isSLoad = true; break; } // If there are odd number of 'S' registers or if it's not 64-bit aligned, // then it takes an extra cycle. if ((isSLoad && (RegNo % 2)) || DefAlign < 8) ++DefCycle; } else { // Assume the worst. DefCycle = RegNo + 2; } return DefCycle; } int ARMBaseInstrInfo::getLDMDefCycle(const InstrItineraryData *ItinData, const MCInstrDesc &DefMCID, unsigned DefClass, unsigned DefIdx, unsigned DefAlign) const { int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1; if (RegNo <= 0) // Def is the address writeback. return ItinData->getOperandCycle(DefClass, DefIdx); int DefCycle; if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { // 4 registers would be issued: 1, 2, 1. // 5 registers would be issued: 1, 2, 2. DefCycle = RegNo / 2; if (DefCycle < 1) DefCycle = 1; // Result latency is issue cycle + 2: E2. DefCycle += 2; } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { DefCycle = (RegNo / 2); // If there are odd number of registers or if it's not 64-bit aligned, // then it takes an extra AGU (Address Generation Unit) cycle. if ((RegNo % 2) || DefAlign < 8) ++DefCycle; // Result latency is AGU cycles + 2. DefCycle += 2; } else { // Assume the worst. DefCycle = RegNo + 2; } return DefCycle; } int ARMBaseInstrInfo::getVSTMUseCycle(const InstrItineraryData *ItinData, const MCInstrDesc &UseMCID, unsigned UseClass, unsigned UseIdx, unsigned UseAlign) const { int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1; if (RegNo <= 0) return ItinData->getOperandCycle(UseClass, UseIdx); int UseCycle; if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { // (regno / 2) + (regno % 2) + 1 UseCycle = RegNo / 2 + 1; if (RegNo % 2) ++UseCycle; } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { UseCycle = RegNo; bool isSStore = false; switch (UseMCID.getOpcode()) { default: break; case ARM::VSTMSIA: case ARM::VSTMSIA_UPD: case ARM::VSTMSDB_UPD: isSStore = true; break; } // If there are odd number of 'S' registers or if it's not 64-bit aligned, // then it takes an extra cycle. if ((isSStore && (RegNo % 2)) || UseAlign < 8) ++UseCycle; } else { // Assume the worst. UseCycle = RegNo + 2; } return UseCycle; } int ARMBaseInstrInfo::getSTMUseCycle(const InstrItineraryData *ItinData, const MCInstrDesc &UseMCID, unsigned UseClass, unsigned UseIdx, unsigned UseAlign) const { int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1; if (RegNo <= 0) return ItinData->getOperandCycle(UseClass, UseIdx); int UseCycle; if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { UseCycle = RegNo / 2; if (UseCycle < 2) UseCycle = 2; // Read in E3. UseCycle += 2; } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { UseCycle = (RegNo / 2); // If there are odd number of registers or if it's not 64-bit aligned, // then it takes an extra AGU (Address Generation Unit) cycle. if ((RegNo % 2) || UseAlign < 8) ++UseCycle; } else { // Assume the worst. UseCycle = 1; } return UseCycle; } int ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, const MCInstrDesc &DefMCID, unsigned DefIdx, unsigned DefAlign, const MCInstrDesc &UseMCID, unsigned UseIdx, unsigned UseAlign) const { unsigned DefClass = DefMCID.getSchedClass(); unsigned UseClass = UseMCID.getSchedClass(); if (DefIdx < DefMCID.getNumDefs() && UseIdx < UseMCID.getNumOperands()) return ItinData->getOperandLatency(DefClass, DefIdx, UseClass, UseIdx); // This may be a def / use of a variable_ops instruction, the operand // latency might be determinable dynamically. Let the target try to // figure it out. int DefCycle = -1; bool LdmBypass = false; switch (DefMCID.getOpcode()) { default: DefCycle = ItinData->getOperandCycle(DefClass, DefIdx); break; case ARM::VLDMDIA: case ARM::VLDMDIA_UPD: case ARM::VLDMDDB_UPD: case ARM::VLDMSIA: case ARM::VLDMSIA_UPD: case ARM::VLDMSDB_UPD: DefCycle = getVLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign); break; case ARM::LDMIA_RET: case ARM::LDMIA: case ARM::LDMDA: case ARM::LDMDB: case ARM::LDMIB: case ARM::LDMIA_UPD: case ARM::LDMDA_UPD: case ARM::LDMDB_UPD: case ARM::LDMIB_UPD: case ARM::tLDMIA: case ARM::tLDMIA_UPD: case ARM::tPUSH: case ARM::t2LDMIA_RET: case ARM::t2LDMIA: case ARM::t2LDMDB: case ARM::t2LDMIA_UPD: case ARM::t2LDMDB_UPD: LdmBypass = 1; DefCycle = getLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign); break; } if (DefCycle == -1) // We can't seem to determine the result latency of the def, assume it's 2. DefCycle = 2; int UseCycle = -1; switch (UseMCID.getOpcode()) { default: UseCycle = ItinData->getOperandCycle(UseClass, UseIdx); break; case ARM::VSTMDIA: case ARM::VSTMDIA_UPD: case ARM::VSTMDDB_UPD: case ARM::VSTMSIA: case ARM::VSTMSIA_UPD: case ARM::VSTMSDB_UPD: UseCycle = getVSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign); break; case ARM::STMIA: case ARM::STMDA: case ARM::STMDB: case ARM::STMIB: case ARM::STMIA_UPD: case ARM::STMDA_UPD: case ARM::STMDB_UPD: case ARM::STMIB_UPD: case ARM::tSTMIA_UPD: case ARM::tPOP_RET: case ARM::tPOP: case ARM::t2STMIA: case ARM::t2STMDB: case ARM::t2STMIA_UPD: case ARM::t2STMDB_UPD: UseCycle = getSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign); break; } if (UseCycle == -1) // Assume it's read in the first stage. UseCycle = 1; UseCycle = DefCycle - UseCycle + 1; if (UseCycle > 0) { if (LdmBypass) { // It's a variable_ops instruction so we can't use DefIdx here. Just use // first def operand. if (ItinData->hasPipelineForwarding(DefClass, DefMCID.getNumOperands()-1, UseClass, UseIdx)) --UseCycle; } else if (ItinData->hasPipelineForwarding(DefClass, DefIdx, UseClass, UseIdx)) { --UseCycle; } } return UseCycle; } static const MachineInstr *getBundledDefMI(const TargetRegisterInfo *TRI, const MachineInstr *MI, unsigned Reg, unsigned &DefIdx, unsigned &Dist) { Dist = 0; MachineBasicBlock::const_iterator I = MI; ++I; MachineBasicBlock::const_instr_iterator II = std::prev(I.getInstrIterator()); assert(II->isInsideBundle() && "Empty bundle?"); int Idx = -1; while (II->isInsideBundle()) { Idx = II->findRegisterDefOperandIdx(Reg, false, true, TRI); if (Idx != -1) break; --II; ++Dist; } assert(Idx != -1 && "Cannot find bundled definition!"); DefIdx = Idx; return II; } static const MachineInstr *getBundledUseMI(const TargetRegisterInfo *TRI, const MachineInstr *MI, unsigned Reg, unsigned &UseIdx, unsigned &Dist) { Dist = 0; MachineBasicBlock::const_instr_iterator II = MI; ++II; assert(II->isInsideBundle() && "Empty bundle?"); MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); // FIXME: This doesn't properly handle multiple uses. int Idx = -1; while (II != E && II->isInsideBundle()) { Idx = II->findRegisterUseOperandIdx(Reg, false, TRI); if (Idx != -1) break; if (II->getOpcode() != ARM::t2IT) ++Dist; ++II; } if (Idx == -1) { Dist = 0; return nullptr; } UseIdx = Idx; return II; } /// Return the number of cycles to add to (or subtract from) the static /// itinerary based on the def opcode and alignment. The caller will ensure that /// adjusted latency is at least one cycle. static int adjustDefLatency(const ARMSubtarget &Subtarget, const MachineInstr *DefMI, const MCInstrDesc *DefMCID, unsigned DefAlign) { int Adjust = 0; if (Subtarget.isCortexA8() || Subtarget.isLikeA9() || Subtarget.isCortexA7()) { // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2] // variants are one cycle cheaper. switch (DefMCID->getOpcode()) { default: break; case ARM::LDRrs: case ARM::LDRBrs: { unsigned ShOpVal = DefMI->getOperand(3).getImm(); unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); if (ShImm == 0 || (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) --Adjust; break; } case ARM::t2LDRs: case ARM::t2LDRBs: case ARM::t2LDRHs: case ARM::t2LDRSHs: { // Thumb2 mode: lsl only. unsigned ShAmt = DefMI->getOperand(3).getImm(); if (ShAmt == 0 || ShAmt == 2) --Adjust; break; } } } else if (Subtarget.isSwift()) { // FIXME: Properly handle all of the latency adjustments for address // writeback. switch (DefMCID->getOpcode()) { default: break; case ARM::LDRrs: case ARM::LDRBrs: { unsigned ShOpVal = DefMI->getOperand(3).getImm(); bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); if (!isSub && (ShImm == 0 || ((ShImm == 1 || ShImm == 2 || ShImm == 3) && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) Adjust -= 2; else if (!isSub && ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr) --Adjust; break; } case ARM::t2LDRs: case ARM::t2LDRBs: case ARM::t2LDRHs: case ARM::t2LDRSHs: { // Thumb2 mode: lsl only. unsigned ShAmt = DefMI->getOperand(3).getImm(); if (ShAmt == 0 || ShAmt == 1 || ShAmt == 2 || ShAmt == 3) Adjust -= 2; break; } } } if (DefAlign < 8 && Subtarget.isLikeA9()) { switch (DefMCID->getOpcode()) { default: break; case ARM::VLD1q8: case ARM::VLD1q16: case ARM::VLD1q32: case ARM::VLD1q64: case ARM::VLD1q8wb_fixed: case ARM::VLD1q16wb_fixed: case ARM::VLD1q32wb_fixed: case ARM::VLD1q64wb_fixed: case ARM::VLD1q8wb_register: case ARM::VLD1q16wb_register: case ARM::VLD1q32wb_register: case ARM::VLD1q64wb_register: case ARM::VLD2d8: case ARM::VLD2d16: case ARM::VLD2d32: case ARM::VLD2q8: case ARM::VLD2q16: case ARM::VLD2q32: case ARM::VLD2d8wb_fixed: case ARM::VLD2d16wb_fixed: case ARM::VLD2d32wb_fixed: case ARM::VLD2q8wb_fixed: case ARM::VLD2q16wb_fixed: case ARM::VLD2q32wb_fixed: case ARM::VLD2d8wb_register: case ARM::VLD2d16wb_register: case ARM::VLD2d32wb_register: case ARM::VLD2q8wb_register: case ARM::VLD2q16wb_register: case ARM::VLD2q32wb_register: case ARM::VLD3d8: case ARM::VLD3d16: case ARM::VLD3d32: case ARM::VLD1d64T: case ARM::VLD3d8_UPD: case ARM::VLD3d16_UPD: case ARM::VLD3d32_UPD: case ARM::VLD1d64Twb_fixed: case ARM::VLD1d64Twb_register: case ARM::VLD3q8_UPD: case ARM::VLD3q16_UPD: case ARM::VLD3q32_UPD: case ARM::VLD4d8: case ARM::VLD4d16: case ARM::VLD4d32: case ARM::VLD1d64Q: case ARM::VLD4d8_UPD: case ARM::VLD4d16_UPD: case ARM::VLD4d32_UPD: case ARM::VLD1d64Qwb_fixed: case ARM::VLD1d64Qwb_register: case ARM::VLD4q8_UPD: case ARM::VLD4q16_UPD: case ARM::VLD4q32_UPD: case ARM::VLD1DUPq8: case ARM::VLD1DUPq16: case ARM::VLD1DUPq32: case ARM::VLD1DUPq8wb_fixed: case ARM::VLD1DUPq16wb_fixed: case ARM::VLD1DUPq32wb_fixed: case ARM::VLD1DUPq8wb_register: case ARM::VLD1DUPq16wb_register: case ARM::VLD1DUPq32wb_register: case ARM::VLD2DUPd8: case ARM::VLD2DUPd16: case ARM::VLD2DUPd32: case ARM::VLD2DUPd8wb_fixed: case ARM::VLD2DUPd16wb_fixed: case ARM::VLD2DUPd32wb_fixed: case ARM::VLD2DUPd8wb_register: case ARM::VLD2DUPd16wb_register: case ARM::VLD2DUPd32wb_register: case ARM::VLD4DUPd8: case ARM::VLD4DUPd16: case ARM::VLD4DUPd32: case ARM::VLD4DUPd8_UPD: case ARM::VLD4DUPd16_UPD: case ARM::VLD4DUPd32_UPD: case ARM::VLD1LNd8: case ARM::VLD1LNd16: case ARM::VLD1LNd32: case ARM::VLD1LNd8_UPD: case ARM::VLD1LNd16_UPD: case ARM::VLD1LNd32_UPD: case ARM::VLD2LNd8: case ARM::VLD2LNd16: case ARM::VLD2LNd32: case ARM::VLD2LNq16: case ARM::VLD2LNq32: case ARM::VLD2LNd8_UPD: case ARM::VLD2LNd16_UPD: case ARM::VLD2LNd32_UPD: case ARM::VLD2LNq16_UPD: case ARM::VLD2LNq32_UPD: case ARM::VLD4LNd8: case ARM::VLD4LNd16: case ARM::VLD4LNd32: case ARM::VLD4LNq16: case ARM::VLD4LNq32: case ARM::VLD4LNd8_UPD: case ARM::VLD4LNd16_UPD: case ARM::VLD4LNd32_UPD: case ARM::VLD4LNq16_UPD: case ARM::VLD4LNq32_UPD: // If the address is not 64-bit aligned, the latencies of these // instructions increases by one. ++Adjust; break; } } return Adjust; } int ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, const MachineInstr *DefMI, unsigned DefIdx, const MachineInstr *UseMI, unsigned UseIdx) const { // No operand latency. The caller may fall back to getInstrLatency. if (!ItinData || ItinData->isEmpty()) return -1; const MachineOperand &DefMO = DefMI->getOperand(DefIdx); unsigned Reg = DefMO.getReg(); const MCInstrDesc *DefMCID = &DefMI->getDesc(); const MCInstrDesc *UseMCID = &UseMI->getDesc(); unsigned DefAdj = 0; if (DefMI->isBundle()) { DefMI = getBundledDefMI(&getRegisterInfo(), DefMI, Reg, DefIdx, DefAdj); DefMCID = &DefMI->getDesc(); } if (DefMI->isCopyLike() || DefMI->isInsertSubreg() || DefMI->isRegSequence() || DefMI->isImplicitDef()) { return 1; } unsigned UseAdj = 0; if (UseMI->isBundle()) { unsigned NewUseIdx; const MachineInstr *NewUseMI = getBundledUseMI(&getRegisterInfo(), UseMI, Reg, NewUseIdx, UseAdj); if (!NewUseMI) return -1; UseMI = NewUseMI; UseIdx = NewUseIdx; UseMCID = &UseMI->getDesc(); } if (Reg == ARM::CPSR) { if (DefMI->getOpcode() == ARM::FMSTAT) { // fpscr -> cpsr stalls over 20 cycles on A8 (and earlier?) return Subtarget.isLikeA9() ? 1 : 20; } // CPSR set and branch can be paired in the same cycle. if (UseMI->isBranch()) return 0; // Otherwise it takes the instruction latency (generally one). unsigned Latency = getInstrLatency(ItinData, DefMI); // For Thumb2 and -Os, prefer scheduling CPSR setting instruction close to // its uses. Instructions which are otherwise scheduled between them may // incur a code size penalty (not able to use the CPSR setting 16-bit // instructions). if (Latency > 0 && Subtarget.isThumb2()) { const MachineFunction *MF = DefMI->getParent()->getParent(); if (MF->getFunction()->hasFnAttribute(Attribute::OptimizeForSize)) --Latency; } return Latency; } if (DefMO.isImplicit() || UseMI->getOperand(UseIdx).isImplicit()) return -1; unsigned DefAlign = DefMI->hasOneMemOperand() ? (*DefMI->memoperands_begin())->getAlignment() : 0; unsigned UseAlign = UseMI->hasOneMemOperand() ? (*UseMI->memoperands_begin())->getAlignment() : 0; // Get the itinerary's latency if possible, and handle variable_ops. int Latency = getOperandLatency(ItinData, *DefMCID, DefIdx, DefAlign, *UseMCID, UseIdx, UseAlign); // Unable to find operand latency. The caller may resort to getInstrLatency. if (Latency < 0) return Latency; // Adjust for IT block position. int Adj = DefAdj + UseAdj; // Adjust for dynamic def-side opcode variants not captured by the itinerary. Adj += adjustDefLatency(Subtarget, DefMI, DefMCID, DefAlign); if (Adj >= 0 || (int)Latency > -Adj) { return Latency + Adj; } // Return the itinerary latency, which may be zero but not less than zero. return Latency; } int ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, SDNode *DefNode, unsigned DefIdx, SDNode *UseNode, unsigned UseIdx) const { if (!DefNode->isMachineOpcode()) return 1; const MCInstrDesc &DefMCID = get(DefNode->getMachineOpcode()); if (isZeroCost(DefMCID.Opcode)) return 0; if (!ItinData || ItinData->isEmpty()) return DefMCID.mayLoad() ? 3 : 1; if (!UseNode->isMachineOpcode()) { int Latency = ItinData->getOperandCycle(DefMCID.getSchedClass(), DefIdx); if (Subtarget.isLikeA9() || Subtarget.isSwift()) return Latency <= 2 ? 1 : Latency - 1; else return Latency <= 3 ? 1 : Latency - 2; } const MCInstrDesc &UseMCID = get(UseNode->getMachineOpcode()); const MachineSDNode *DefMN = dyn_cast(DefNode); unsigned DefAlign = !DefMN->memoperands_empty() ? (*DefMN->memoperands_begin())->getAlignment() : 0; const MachineSDNode *UseMN = dyn_cast(UseNode); unsigned UseAlign = !UseMN->memoperands_empty() ? (*UseMN->memoperands_begin())->getAlignment() : 0; int Latency = getOperandLatency(ItinData, DefMCID, DefIdx, DefAlign, UseMCID, UseIdx, UseAlign); if (Latency > 1 && (Subtarget.isCortexA8() || Subtarget.isLikeA9() || Subtarget.isCortexA7())) { // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2] // variants are one cycle cheaper. switch (DefMCID.getOpcode()) { default: break; case ARM::LDRrs: case ARM::LDRBrs: { unsigned ShOpVal = cast(DefNode->getOperand(2))->getZExtValue(); unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); if (ShImm == 0 || (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) --Latency; break; } case ARM::t2LDRs: case ARM::t2LDRBs: case ARM::t2LDRHs: case ARM::t2LDRSHs: { // Thumb2 mode: lsl only. unsigned ShAmt = cast(DefNode->getOperand(2))->getZExtValue(); if (ShAmt == 0 || ShAmt == 2) --Latency; break; } } } else if (DefIdx == 0 && Latency > 2 && Subtarget.isSwift()) { // FIXME: Properly handle all of the latency adjustments for address // writeback. switch (DefMCID.getOpcode()) { default: break; case ARM::LDRrs: case ARM::LDRBrs: { unsigned ShOpVal = cast(DefNode->getOperand(2))->getZExtValue(); unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); if (ShImm == 0 || ((ShImm == 1 || ShImm == 2 || ShImm == 3) && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) Latency -= 2; else if (ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr) --Latency; break; } case ARM::t2LDRs: case ARM::t2LDRBs: case ARM::t2LDRHs: case ARM::t2LDRSHs: { // Thumb2 mode: lsl 0-3 only. Latency -= 2; break; } } } if (DefAlign < 8 && Subtarget.isLikeA9()) switch (DefMCID.getOpcode()) { default: break; case ARM::VLD1q8: case ARM::VLD1q16: case ARM::VLD1q32: case ARM::VLD1q64: case ARM::VLD1q8wb_register: case ARM::VLD1q16wb_register: case ARM::VLD1q32wb_register: case ARM::VLD1q64wb_register: case ARM::VLD1q8wb_fixed: case ARM::VLD1q16wb_fixed: case ARM::VLD1q32wb_fixed: case ARM::VLD1q64wb_fixed: case ARM::VLD2d8: case ARM::VLD2d16: case ARM::VLD2d32: case ARM::VLD2q8Pseudo: case ARM::VLD2q16Pseudo: case ARM::VLD2q32Pseudo: case ARM::VLD2d8wb_fixed: case ARM::VLD2d16wb_fixed: case ARM::VLD2d32wb_fixed: case ARM::VLD2q8PseudoWB_fixed: case ARM::VLD2q16PseudoWB_fixed: case ARM::VLD2q32PseudoWB_fixed: case ARM::VLD2d8wb_register: case ARM::VLD2d16wb_register: case ARM::VLD2d32wb_register: case ARM::VLD2q8PseudoWB_register: case ARM::VLD2q16PseudoWB_register: case ARM::VLD2q32PseudoWB_register: case ARM::VLD3d8Pseudo: case ARM::VLD3d16Pseudo: case ARM::VLD3d32Pseudo: case ARM::VLD1d64TPseudo: case ARM::VLD1d64TPseudoWB_fixed: case ARM::VLD3d8Pseudo_UPD: case ARM::VLD3d16Pseudo_UPD: case ARM::VLD3d32Pseudo_UPD: case ARM::VLD3q8Pseudo_UPD: case ARM::VLD3q16Pseudo_UPD: case ARM::VLD3q32Pseudo_UPD: case ARM::VLD3q8oddPseudo: case ARM::VLD3q16oddPseudo: case ARM::VLD3q32oddPseudo: case ARM::VLD3q8oddPseudo_UPD: case ARM::VLD3q16oddPseudo_UPD: case ARM::VLD3q32oddPseudo_UPD: case ARM::VLD4d8Pseudo: case ARM::VLD4d16Pseudo: case ARM::VLD4d32Pseudo: case ARM::VLD1d64QPseudo: case ARM::VLD1d64QPseudoWB_fixed: case ARM::VLD4d8Pseudo_UPD: case ARM::VLD4d16Pseudo_UPD: case ARM::VLD4d32Pseudo_UPD: case ARM::VLD4q8Pseudo_UPD: case ARM::VLD4q16Pseudo_UPD: case ARM::VLD4q32Pseudo_UPD: case ARM::VLD4q8oddPseudo: case ARM::VLD4q16oddPseudo: case ARM::VLD4q32oddPseudo: case ARM::VLD4q8oddPseudo_UPD: case ARM::VLD4q16oddPseudo_UPD: case ARM::VLD4q32oddPseudo_UPD: case ARM::VLD1DUPq8: case ARM::VLD1DUPq16: case ARM::VLD1DUPq32: case ARM::VLD1DUPq8wb_fixed: case ARM::VLD1DUPq16wb_fixed: case ARM::VLD1DUPq32wb_fixed: case ARM::VLD1DUPq8wb_register: case ARM::VLD1DUPq16wb_register: case ARM::VLD1DUPq32wb_register: case ARM::VLD2DUPd8: case ARM::VLD2DUPd16: case ARM::VLD2DUPd32: case ARM::VLD2DUPd8wb_fixed: case ARM::VLD2DUPd16wb_fixed: case ARM::VLD2DUPd32wb_fixed: case ARM::VLD2DUPd8wb_register: case ARM::VLD2DUPd16wb_register: case ARM::VLD2DUPd32wb_register: case ARM::VLD4DUPd8Pseudo: case ARM::VLD4DUPd16Pseudo: case ARM::VLD4DUPd32Pseudo: case ARM::VLD4DUPd8Pseudo_UPD: case ARM::VLD4DUPd16Pseudo_UPD: case ARM::VLD4DUPd32Pseudo_UPD: case ARM::VLD1LNq8Pseudo: case ARM::VLD1LNq16Pseudo: case ARM::VLD1LNq32Pseudo: case ARM::VLD1LNq8Pseudo_UPD: case ARM::VLD1LNq16Pseudo_UPD: case ARM::VLD1LNq32Pseudo_UPD: case ARM::VLD2LNd8Pseudo: case ARM::VLD2LNd16Pseudo: case ARM::VLD2LNd32Pseudo: case ARM::VLD2LNq16Pseudo: case ARM::VLD2LNq32Pseudo: case ARM::VLD2LNd8Pseudo_UPD: case ARM::VLD2LNd16Pseudo_UPD: case ARM::VLD2LNd32Pseudo_UPD: case ARM::VLD2LNq16Pseudo_UPD: case ARM::VLD2LNq32Pseudo_UPD: case ARM::VLD4LNd8Pseudo: case ARM::VLD4LNd16Pseudo: case ARM::VLD4LNd32Pseudo: case ARM::VLD4LNq16Pseudo: case ARM::VLD4LNq32Pseudo: case ARM::VLD4LNd8Pseudo_UPD: case ARM::VLD4LNd16Pseudo_UPD: case ARM::VLD4LNd32Pseudo_UPD: case ARM::VLD4LNq16Pseudo_UPD: case ARM::VLD4LNq32Pseudo_UPD: // If the address is not 64-bit aligned, the latencies of these // instructions increases by one. ++Latency; break; } return Latency; } unsigned ARMBaseInstrInfo::getPredicationCost(const MachineInstr *MI) const { if (MI->isCopyLike() || MI->isInsertSubreg() || MI->isRegSequence() || MI->isImplicitDef()) return 0; if (MI->isBundle()) return 0; const MCInstrDesc &MCID = MI->getDesc(); if (MCID.isCall() || MCID.hasImplicitDefOfPhysReg(ARM::CPSR)) { // When predicated, CPSR is an additional source operand for CPSR updating // instructions, this apparently increases their latencies. return 1; } return 0; } unsigned ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData, const MachineInstr *MI, unsigned *PredCost) const { if (MI->isCopyLike() || MI->isInsertSubreg() || MI->isRegSequence() || MI->isImplicitDef()) return 1; // An instruction scheduler typically runs on unbundled instructions, however // other passes may query the latency of a bundled instruction. if (MI->isBundle()) { unsigned Latency = 0; MachineBasicBlock::const_instr_iterator I = MI; MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); while (++I != E && I->isInsideBundle()) { if (I->getOpcode() != ARM::t2IT) Latency += getInstrLatency(ItinData, I, PredCost); } return Latency; } const MCInstrDesc &MCID = MI->getDesc(); if (PredCost && (MCID.isCall() || MCID.hasImplicitDefOfPhysReg(ARM::CPSR))) { // When predicated, CPSR is an additional source operand for CPSR updating // instructions, this apparently increases their latencies. *PredCost = 1; } // Be sure to call getStageLatency for an empty itinerary in case it has a // valid MinLatency property. if (!ItinData) return MI->mayLoad() ? 3 : 1; unsigned Class = MCID.getSchedClass(); // For instructions with variable uops, use uops as latency. if (!ItinData->isEmpty() && ItinData->getNumMicroOps(Class) < 0) return getNumMicroOps(ItinData, MI); // For the common case, fall back on the itinerary's latency. unsigned Latency = ItinData->getStageLatency(Class); // Adjust for dynamic def-side opcode variants not captured by the itinerary. unsigned DefAlign = MI->hasOneMemOperand() ? (*MI->memoperands_begin())->getAlignment() : 0; int Adj = adjustDefLatency(Subtarget, MI, &MCID, DefAlign); if (Adj >= 0 || (int)Latency > -Adj) { return Latency + Adj; } return Latency; } int ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData, SDNode *Node) const { if (!Node->isMachineOpcode()) return 1; if (!ItinData || ItinData->isEmpty()) return 1; unsigned Opcode = Node->getMachineOpcode(); switch (Opcode) { default: return ItinData->getStageLatency(get(Opcode).getSchedClass()); case ARM::VLDMQIA: case ARM::VSTMQIA: return 2; } } bool ARMBaseInstrInfo:: hasHighOperandLatency(const TargetSchedModel &SchedModel, const MachineRegisterInfo *MRI, const MachineInstr *DefMI, unsigned DefIdx, const MachineInstr *UseMI, unsigned UseIdx) const { unsigned DDomain = DefMI->getDesc().TSFlags & ARMII::DomainMask; unsigned UDomain = UseMI->getDesc().TSFlags & ARMII::DomainMask; if (Subtarget.isCortexA8() && (DDomain == ARMII::DomainVFP || UDomain == ARMII::DomainVFP)) // CortexA8 VFP instructions are not pipelined. return true; // Hoist VFP / NEON instructions with 4 or higher latency. unsigned Latency = SchedModel.computeOperandLatency(DefMI, DefIdx, UseMI, UseIdx); if (Latency <= 3) return false; return DDomain == ARMII::DomainVFP || DDomain == ARMII::DomainNEON || UDomain == ARMII::DomainVFP || UDomain == ARMII::DomainNEON; } bool ARMBaseInstrInfo:: hasLowDefLatency(const TargetSchedModel &SchedModel, const MachineInstr *DefMI, unsigned DefIdx) const { const InstrItineraryData *ItinData = SchedModel.getInstrItineraries(); if (!ItinData || ItinData->isEmpty()) return false; unsigned DDomain = DefMI->getDesc().TSFlags & ARMII::DomainMask; if (DDomain == ARMII::DomainGeneral) { unsigned DefClass = DefMI->getDesc().getSchedClass(); int DefCycle = ItinData->getOperandCycle(DefClass, DefIdx); return (DefCycle != -1 && DefCycle <= 2); } return false; } bool ARMBaseInstrInfo::verifyInstruction(const MachineInstr *MI, StringRef &ErrInfo) const { if (convertAddSubFlagsOpcode(MI->getOpcode())) { ErrInfo = "Pseudo flag setting opcodes only exist in Selection DAG"; return false; } return true; } // LoadStackGuard has so far only been implemented for MachO. Different code // sequence is needed for other targets. void ARMBaseInstrInfo::expandLoadStackGuardBase(MachineBasicBlock::iterator MI, unsigned LoadImmOpc, unsigned LoadOpc, Reloc::Model RM) const { MachineBasicBlock &MBB = *MI->getParent(); DebugLoc DL = MI->getDebugLoc(); unsigned Reg = MI->getOperand(0).getReg(); const GlobalValue *GV = cast((*MI->memoperands_begin())->getValue()); MachineInstrBuilder MIB; BuildMI(MBB, MI, DL, get(LoadImmOpc), Reg) .addGlobalAddress(GV, 0, ARMII::MO_NONLAZY); if (Subtarget.GVIsIndirectSymbol(GV, RM)) { MIB = BuildMI(MBB, MI, DL, get(LoadOpc), Reg); MIB.addReg(Reg, RegState::Kill).addImm(0); unsigned Flag = MachineMemOperand::MOLoad | MachineMemOperand::MOInvariant; MachineMemOperand *MMO = MBB.getParent()-> getMachineMemOperand(MachinePointerInfo::getGOT(), Flag, 4, 4); MIB.addMemOperand(MMO); AddDefaultPred(MIB); } MIB = BuildMI(MBB, MI, DL, get(LoadOpc), Reg); MIB.addReg(Reg, RegState::Kill).addImm(0); MIB.setMemRefs(MI->memoperands_begin(), MI->memoperands_end()); AddDefaultPred(MIB); } bool ARMBaseInstrInfo::isFpMLxInstruction(unsigned Opcode, unsigned &MulOpc, unsigned &AddSubOpc, bool &NegAcc, bool &HasLane) const { DenseMap::const_iterator I = MLxEntryMap.find(Opcode); if (I == MLxEntryMap.end()) return false; const ARM_MLxEntry &Entry = ARM_MLxTable[I->second]; MulOpc = Entry.MulOpc; AddSubOpc = Entry.AddSubOpc; NegAcc = Entry.NegAcc; HasLane = Entry.HasLane; return true; } //===----------------------------------------------------------------------===// // Execution domains. //===----------------------------------------------------------------------===// // // Some instructions go down the NEON pipeline, some go down the VFP pipeline, // and some can go down both. The vmov instructions go down the VFP pipeline, // but they can be changed to vorr equivalents that are executed by the NEON // pipeline. // // We use the following execution domain numbering: // enum ARMExeDomain { ExeGeneric = 0, ExeVFP = 1, ExeNEON = 2 }; // // Also see ARMInstrFormats.td and Domain* enums in ARMBaseInfo.h // std::pair ARMBaseInstrInfo::getExecutionDomain(const MachineInstr *MI) const { // If we don't have access to NEON instructions then we won't be able // to swizzle anything to the NEON domain. Check to make sure. if (Subtarget.hasNEON()) { // VMOVD, VMOVRS and VMOVSR are VFP instructions, but can be changed to NEON // if they are not predicated. if (MI->getOpcode() == ARM::VMOVD && !isPredicated(MI)) return std::make_pair(ExeVFP, (1 << ExeVFP) | (1 << ExeNEON)); // CortexA9 is particularly picky about mixing the two and wants these // converted. if (Subtarget.isCortexA9() && !isPredicated(MI) && (MI->getOpcode() == ARM::VMOVRS || MI->getOpcode() == ARM::VMOVSR || MI->getOpcode() == ARM::VMOVS)) return std::make_pair(ExeVFP, (1 << ExeVFP) | (1 << ExeNEON)); } // No other instructions can be swizzled, so just determine their domain. unsigned Domain = MI->getDesc().TSFlags & ARMII::DomainMask; if (Domain & ARMII::DomainNEON) return std::make_pair(ExeNEON, 0); // Certain instructions can go either way on Cortex-A8. // Treat them as NEON instructions. if ((Domain & ARMII::DomainNEONA8) && Subtarget.isCortexA8()) return std::make_pair(ExeNEON, 0); if (Domain & ARMII::DomainVFP) return std::make_pair(ExeVFP, 0); return std::make_pair(ExeGeneric, 0); } static unsigned getCorrespondingDRegAndLane(const TargetRegisterInfo *TRI, unsigned SReg, unsigned &Lane) { unsigned DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_0, &ARM::DPRRegClass); Lane = 0; if (DReg != ARM::NoRegister) return DReg; Lane = 1; DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_1, &ARM::DPRRegClass); assert(DReg && "S-register with no D super-register?"); return DReg; } /// getImplicitSPRUseForDPRUse - Given a use of a DPR register and lane, /// set ImplicitSReg to a register number that must be marked as implicit-use or /// zero if no register needs to be defined as implicit-use. /// /// If the function cannot determine if an SPR should be marked implicit use or /// not, it returns false. /// /// This function handles cases where an instruction is being modified from taking /// an SPR to a DPR[Lane]. A use of the DPR is being added, which may conflict /// with an earlier def of an SPR corresponding to DPR[Lane^1] (i.e. the other /// lane of the DPR). /// /// If the other SPR is defined, an implicit-use of it should be added. Else, /// (including the case where the DPR itself is defined), it should not. /// static bool getImplicitSPRUseForDPRUse(const TargetRegisterInfo *TRI, MachineInstr *MI, unsigned DReg, unsigned Lane, unsigned &ImplicitSReg) { // If the DPR is defined or used already, the other SPR lane will be chained // correctly, so there is nothing to be done. if (MI->definesRegister(DReg, TRI) || MI->readsRegister(DReg, TRI)) { ImplicitSReg = 0; return true; } // Otherwise we need to go searching to see if the SPR is set explicitly. ImplicitSReg = TRI->getSubReg(DReg, (Lane & 1) ? ARM::ssub_0 : ARM::ssub_1); MachineBasicBlock::LivenessQueryResult LQR = MI->getParent()->computeRegisterLiveness(TRI, ImplicitSReg, MI); if (LQR == MachineBasicBlock::LQR_Live) return true; else if (LQR == MachineBasicBlock::LQR_Unknown) return false; // If the register is known not to be live, there is no need to add an // implicit-use. ImplicitSReg = 0; return true; } void ARMBaseInstrInfo::setExecutionDomain(MachineInstr *MI, unsigned Domain) const { unsigned DstReg, SrcReg, DReg; unsigned Lane; MachineInstrBuilder MIB(*MI->getParent()->getParent(), MI); const TargetRegisterInfo *TRI = &getRegisterInfo(); switch (MI->getOpcode()) { default: llvm_unreachable("cannot handle opcode!"); break; case ARM::VMOVD: if (Domain != ExeNEON) break; // Zap the predicate operands. assert(!isPredicated(MI) && "Cannot predicate a VORRd"); // Make sure we've got NEON instructions. assert(Subtarget.hasNEON() && "VORRd requires NEON"); // Source instruction is %DDst = VMOVD %DSrc, 14, %noreg (; implicits) DstReg = MI->getOperand(0).getReg(); SrcReg = MI->getOperand(1).getReg(); for (unsigned i = MI->getDesc().getNumOperands(); i; --i) MI->RemoveOperand(i-1); // Change to a %DDst = VORRd %DSrc, %DSrc, 14, %noreg (; implicits) MI->setDesc(get(ARM::VORRd)); AddDefaultPred(MIB.addReg(DstReg, RegState::Define) .addReg(SrcReg) .addReg(SrcReg)); break; case ARM::VMOVRS: if (Domain != ExeNEON) break; assert(!isPredicated(MI) && "Cannot predicate a VGETLN"); // Source instruction is %RDst = VMOVRS %SSrc, 14, %noreg (; implicits) DstReg = MI->getOperand(0).getReg(); SrcReg = MI->getOperand(1).getReg(); for (unsigned i = MI->getDesc().getNumOperands(); i; --i) MI->RemoveOperand(i-1); DReg = getCorrespondingDRegAndLane(TRI, SrcReg, Lane); // Convert to %RDst = VGETLNi32 %DSrc, Lane, 14, %noreg (; imps) // Note that DSrc has been widened and the other lane may be undef, which // contaminates the entire register. MI->setDesc(get(ARM::VGETLNi32)); AddDefaultPred(MIB.addReg(DstReg, RegState::Define) .addReg(DReg, RegState::Undef) .addImm(Lane)); // The old source should be an implicit use, otherwise we might think it // was dead before here. MIB.addReg(SrcReg, RegState::Implicit); break; case ARM::VMOVSR: { if (Domain != ExeNEON) break; assert(!isPredicated(MI) && "Cannot predicate a VSETLN"); // Source instruction is %SDst = VMOVSR %RSrc, 14, %noreg (; implicits) DstReg = MI->getOperand(0).getReg(); SrcReg = MI->getOperand(1).getReg(); DReg = getCorrespondingDRegAndLane(TRI, DstReg, Lane); unsigned ImplicitSReg; if (!getImplicitSPRUseForDPRUse(TRI, MI, DReg, Lane, ImplicitSReg)) break; for (unsigned i = MI->getDesc().getNumOperands(); i; --i) MI->RemoveOperand(i-1); // Convert to %DDst = VSETLNi32 %DDst, %RSrc, Lane, 14, %noreg (; imps) // Again DDst may be undefined at the beginning of this instruction. MI->setDesc(get(ARM::VSETLNi32)); MIB.addReg(DReg, RegState::Define) .addReg(DReg, getUndefRegState(!MI->readsRegister(DReg, TRI))) .addReg(SrcReg) .addImm(Lane); AddDefaultPred(MIB); // The narrower destination must be marked as set to keep previous chains // in place. MIB.addReg(DstReg, RegState::Define | RegState::Implicit); if (ImplicitSReg != 0) MIB.addReg(ImplicitSReg, RegState::Implicit); break; } case ARM::VMOVS: { if (Domain != ExeNEON) break; // Source instruction is %SDst = VMOVS %SSrc, 14, %noreg (; implicits) DstReg = MI->getOperand(0).getReg(); SrcReg = MI->getOperand(1).getReg(); unsigned DstLane = 0, SrcLane = 0, DDst, DSrc; DDst = getCorrespondingDRegAndLane(TRI, DstReg, DstLane); DSrc = getCorrespondingDRegAndLane(TRI, SrcReg, SrcLane); unsigned ImplicitSReg; if (!getImplicitSPRUseForDPRUse(TRI, MI, DSrc, SrcLane, ImplicitSReg)) break; for (unsigned i = MI->getDesc().getNumOperands(); i; --i) MI->RemoveOperand(i-1); if (DSrc == DDst) { // Destination can be: // %DDst = VDUPLN32d %DDst, Lane, 14, %noreg (; implicits) MI->setDesc(get(ARM::VDUPLN32d)); MIB.addReg(DDst, RegState::Define) .addReg(DDst, getUndefRegState(!MI->readsRegister(DDst, TRI))) .addImm(SrcLane); AddDefaultPred(MIB); // Neither the source or the destination are naturally represented any // more, so add them in manually. MIB.addReg(DstReg, RegState::Implicit | RegState::Define); MIB.addReg(SrcReg, RegState::Implicit); if (ImplicitSReg != 0) MIB.addReg(ImplicitSReg, RegState::Implicit); break; } // In general there's no single instruction that can perform an S <-> S // move in NEON space, but a pair of VEXT instructions *can* do the // job. It turns out that the VEXTs needed will only use DSrc once, with // the position based purely on the combination of lane-0 and lane-1 // involved. For example // vmov s0, s2 -> vext.32 d0, d0, d1, #1 vext.32 d0, d0, d0, #1 // vmov s1, s3 -> vext.32 d0, d1, d0, #1 vext.32 d0, d0, d0, #1 // vmov s0, s3 -> vext.32 d0, d0, d0, #1 vext.32 d0, d1, d0, #1 // vmov s1, s2 -> vext.32 d0, d0, d0, #1 vext.32 d0, d0, d1, #1 // // Pattern of the MachineInstrs is: // %DDst = VEXTd32 %DSrc1, %DSrc2, Lane, 14, %noreg (;implicits) MachineInstrBuilder NewMIB; NewMIB = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(), get(ARM::VEXTd32), DDst); // On the first instruction, both DSrc and DDst may be if present. // Specifically when the original instruction didn't have them as an // . unsigned CurReg = SrcLane == 1 && DstLane == 1 ? DSrc : DDst; bool CurUndef = !MI->readsRegister(CurReg, TRI); NewMIB.addReg(CurReg, getUndefRegState(CurUndef)); CurReg = SrcLane == 0 && DstLane == 0 ? DSrc : DDst; CurUndef = !MI->readsRegister(CurReg, TRI); NewMIB.addReg(CurReg, getUndefRegState(CurUndef)); NewMIB.addImm(1); AddDefaultPred(NewMIB); if (SrcLane == DstLane) NewMIB.addReg(SrcReg, RegState::Implicit); MI->setDesc(get(ARM::VEXTd32)); MIB.addReg(DDst, RegState::Define); // On the second instruction, DDst has definitely been defined above, so // it is not . DSrc, if present, can be as above. CurReg = SrcLane == 1 && DstLane == 0 ? DSrc : DDst; CurUndef = CurReg == DSrc && !MI->readsRegister(CurReg, TRI); MIB.addReg(CurReg, getUndefRegState(CurUndef)); CurReg = SrcLane == 0 && DstLane == 1 ? DSrc : DDst; CurUndef = CurReg == DSrc && !MI->readsRegister(CurReg, TRI); MIB.addReg(CurReg, getUndefRegState(CurUndef)); MIB.addImm(1); AddDefaultPred(MIB); if (SrcLane != DstLane) MIB.addReg(SrcReg, RegState::Implicit); // As before, the original destination is no longer represented, add it // implicitly. MIB.addReg(DstReg, RegState::Define | RegState::Implicit); if (ImplicitSReg != 0) MIB.addReg(ImplicitSReg, RegState::Implicit); break; } } } //===----------------------------------------------------------------------===// // Partial register updates //===----------------------------------------------------------------------===// // // Swift renames NEON registers with 64-bit granularity. That means any // instruction writing an S-reg implicitly reads the containing D-reg. The // problem is mostly avoided by translating f32 operations to v2f32 operations // on D-registers, but f32 loads are still a problem. // // These instructions can load an f32 into a NEON register: // // VLDRS - Only writes S, partial D update. // VLD1LNd32 - Writes all D-regs, explicit partial D update, 2 uops. // VLD1DUPd32 - Writes all D-regs, no partial reg update, 2 uops. // // FCONSTD can be used as a dependency-breaking instruction. unsigned ARMBaseInstrInfo:: getPartialRegUpdateClearance(const MachineInstr *MI, unsigned OpNum, const TargetRegisterInfo *TRI) const { if (!SwiftPartialUpdateClearance || !(Subtarget.isSwift() || Subtarget.isCortexA15())) return 0; assert(TRI && "Need TRI instance"); const MachineOperand &MO = MI->getOperand(OpNum); if (MO.readsReg()) return 0; unsigned Reg = MO.getReg(); int UseOp = -1; switch(MI->getOpcode()) { // Normal instructions writing only an S-register. case ARM::VLDRS: case ARM::FCONSTS: case ARM::VMOVSR: case ARM::VMOVv8i8: case ARM::VMOVv4i16: case ARM::VMOVv2i32: case ARM::VMOVv2f32: case ARM::VMOVv1i64: UseOp = MI->findRegisterUseOperandIdx(Reg, false, TRI); break; // Explicitly reads the dependency. case ARM::VLD1LNd32: UseOp = 3; break; default: return 0; } // If this instruction actually reads a value from Reg, there is no unwanted // dependency. if (UseOp != -1 && MI->getOperand(UseOp).readsReg()) return 0; // We must be able to clobber the whole D-reg. if (TargetRegisterInfo::isVirtualRegister(Reg)) { // Virtual register must be a foo:ssub_0 operand. if (!MO.getSubReg() || MI->readsVirtualRegister(Reg)) return 0; } else if (ARM::SPRRegClass.contains(Reg)) { // Physical register: MI must define the full D-reg. unsigned DReg = TRI->getMatchingSuperReg(Reg, ARM::ssub_0, &ARM::DPRRegClass); if (!DReg || !MI->definesRegister(DReg, TRI)) return 0; } // MI has an unwanted D-register dependency. // Avoid defs in the previous N instructrions. return SwiftPartialUpdateClearance; } // Break a partial register dependency after getPartialRegUpdateClearance // returned non-zero. void ARMBaseInstrInfo:: breakPartialRegDependency(MachineBasicBlock::iterator MI, unsigned OpNum, const TargetRegisterInfo *TRI) const { assert(MI && OpNum < MI->getDesc().getNumDefs() && "OpNum is not a def"); assert(TRI && "Need TRI instance"); const MachineOperand &MO = MI->getOperand(OpNum); unsigned Reg = MO.getReg(); assert(TargetRegisterInfo::isPhysicalRegister(Reg) && "Can't break virtual register dependencies."); unsigned DReg = Reg; // If MI defines an S-reg, find the corresponding D super-register. if (ARM::SPRRegClass.contains(Reg)) { DReg = ARM::D0 + (Reg - ARM::S0) / 2; assert(TRI->isSuperRegister(Reg, DReg) && "Register enums broken"); } assert(ARM::DPRRegClass.contains(DReg) && "Can only break D-reg deps"); assert(MI->definesRegister(DReg, TRI) && "MI doesn't clobber full D-reg"); // FIXME: In some cases, VLDRS can be changed to a VLD1DUPd32 which defines // the full D-register by loading the same value to both lanes. The // instruction is micro-coded with 2 uops, so don't do this until we can // properly schedule micro-coded instructions. The dispatcher stalls cause // too big regressions. // Insert the dependency-breaking FCONSTD before MI. // 96 is the encoding of 0.5, but the actual value doesn't matter here. AddDefaultPred(BuildMI(*MI->getParent(), MI, MI->getDebugLoc(), get(ARM::FCONSTD), DReg).addImm(96)); MI->addRegisterKilled(DReg, TRI, true); } bool ARMBaseInstrInfo::hasNOP() const { return Subtarget.getFeatureBits()[ARM::HasV6KOps]; } bool ARMBaseInstrInfo::isSwiftFastImmShift(const MachineInstr *MI) const { if (MI->getNumOperands() < 4) return true; unsigned ShOpVal = MI->getOperand(3).getImm(); unsigned ShImm = ARM_AM::getSORegOffset(ShOpVal); // Swift supports faster shifts for: lsl 2, lsl 1, and lsr 1. if ((ShImm == 1 && ARM_AM::getSORegShOp(ShOpVal) == ARM_AM::lsr) || ((ShImm == 1 || ShImm == 2) && ARM_AM::getSORegShOp(ShOpVal) == ARM_AM::lsl)) return true; return false; } bool ARMBaseInstrInfo::getRegSequenceLikeInputs( const MachineInstr &MI, unsigned DefIdx, SmallVectorImpl &InputRegs) const { assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index"); assert(MI.isRegSequenceLike() && "Invalid kind of instruction"); switch (MI.getOpcode()) { case ARM::VMOVDRR: // dX = VMOVDRR rY, rZ // is the same as: // dX = REG_SEQUENCE rY, ssub_0, rZ, ssub_1 // Populate the InputRegs accordingly. // rY const MachineOperand *MOReg = &MI.getOperand(1); InputRegs.push_back( RegSubRegPairAndIdx(MOReg->getReg(), MOReg->getSubReg(), ARM::ssub_0)); // rZ MOReg = &MI.getOperand(2); InputRegs.push_back( RegSubRegPairAndIdx(MOReg->getReg(), MOReg->getSubReg(), ARM::ssub_1)); return true; } llvm_unreachable("Target dependent opcode missing"); } bool ARMBaseInstrInfo::getExtractSubregLikeInputs( const MachineInstr &MI, unsigned DefIdx, RegSubRegPairAndIdx &InputReg) const { assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index"); assert(MI.isExtractSubregLike() && "Invalid kind of instruction"); switch (MI.getOpcode()) { case ARM::VMOVRRD: // rX, rY = VMOVRRD dZ // is the same as: // rX = EXTRACT_SUBREG dZ, ssub_0 // rY = EXTRACT_SUBREG dZ, ssub_1 const MachineOperand &MOReg = MI.getOperand(2); InputReg.Reg = MOReg.getReg(); InputReg.SubReg = MOReg.getSubReg(); InputReg.SubIdx = DefIdx == 0 ? ARM::ssub_0 : ARM::ssub_1; return true; } llvm_unreachable("Target dependent opcode missing"); } bool ARMBaseInstrInfo::getInsertSubregLikeInputs( const MachineInstr &MI, unsigned DefIdx, RegSubRegPair &BaseReg, RegSubRegPairAndIdx &InsertedReg) const { assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index"); assert(MI.isInsertSubregLike() && "Invalid kind of instruction"); switch (MI.getOpcode()) { case ARM::VSETLNi32: // dX = VSETLNi32 dY, rZ, imm const MachineOperand &MOBaseReg = MI.getOperand(1); const MachineOperand &MOInsertedReg = MI.getOperand(2); const MachineOperand &MOIndex = MI.getOperand(3); BaseReg.Reg = MOBaseReg.getReg(); BaseReg.SubReg = MOBaseReg.getSubReg(); InsertedReg.Reg = MOInsertedReg.getReg(); InsertedReg.SubReg = MOInsertedReg.getSubReg(); InsertedReg.SubIdx = MOIndex.getImm() == 0 ? ARM::ssub_0 : ARM::ssub_1; return true; } llvm_unreachable("Target dependent opcode missing"); }