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      1 //===-- ARMBaseInstrInfo.cpp - ARM Instruction Information ----------------===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // This file contains the Base ARM implementation of the TargetInstrInfo class.
     11 //
     12 //===----------------------------------------------------------------------===//
     13 
     14 #include "ARM.h"
     15 #include "ARMBaseInstrInfo.h"
     16 #include "ARMBaseRegisterInfo.h"
     17 #include "ARMConstantPoolValue.h"
     18 #include "ARMFeatures.h"
     19 #include "ARMHazardRecognizer.h"
     20 #include "ARMMachineFunctionInfo.h"
     21 #include "MCTargetDesc/ARMAddressingModes.h"
     22 #include "llvm/ADT/STLExtras.h"
     23 #include "llvm/CodeGen/LiveVariables.h"
     24 #include "llvm/CodeGen/MachineConstantPool.h"
     25 #include "llvm/CodeGen/MachineFrameInfo.h"
     26 #include "llvm/CodeGen/MachineInstrBuilder.h"
     27 #include "llvm/CodeGen/MachineJumpTableInfo.h"
     28 #include "llvm/CodeGen/MachineMemOperand.h"
     29 #include "llvm/CodeGen/MachineRegisterInfo.h"
     30 #include "llvm/CodeGen/SelectionDAGNodes.h"
     31 #include "llvm/CodeGen/TargetSchedule.h"
     32 #include "llvm/IR/Constants.h"
     33 #include "llvm/IR/Function.h"
     34 #include "llvm/IR/GlobalValue.h"
     35 #include "llvm/MC/MCAsmInfo.h"
     36 #include "llvm/MC/MCExpr.h"
     37 #include "llvm/Support/BranchProbability.h"
     38 #include "llvm/Support/CommandLine.h"
     39 #include "llvm/Support/Debug.h"
     40 #include "llvm/Support/ErrorHandling.h"
     41 #include "llvm/Support/raw_ostream.h"
     42 
     43 using namespace llvm;
     44 
     45 #define DEBUG_TYPE "arm-instrinfo"
     46 
     47 #define GET_INSTRINFO_CTOR_DTOR
     48 #include "ARMGenInstrInfo.inc"
     49 
     50 static cl::opt<bool>
     51 EnableARM3Addr("enable-arm-3-addr-conv", cl::Hidden,
     52                cl::desc("Enable ARM 2-addr to 3-addr conv"));
     53 
     54 static cl::opt<bool>
     55 WidenVMOVS("widen-vmovs", cl::Hidden, cl::init(true),
     56            cl::desc("Widen ARM vmovs to vmovd when possible"));
     57 
     58 static cl::opt<unsigned>
     59 SwiftPartialUpdateClearance("swift-partial-update-clearance",
     60      cl::Hidden, cl::init(12),
     61      cl::desc("Clearance before partial register updates"));
     62 
     63 /// ARM_MLxEntry - Record information about MLA / MLS instructions.
     64 struct ARM_MLxEntry {
     65   uint16_t MLxOpc;     // MLA / MLS opcode
     66   uint16_t MulOpc;     // Expanded multiplication opcode
     67   uint16_t AddSubOpc;  // Expanded add / sub opcode
     68   bool NegAcc;         // True if the acc is negated before the add / sub.
     69   bool HasLane;        // True if instruction has an extra "lane" operand.
     70 };
     71 
     72 static const ARM_MLxEntry ARM_MLxTable[] = {
     73   // MLxOpc,          MulOpc,           AddSubOpc,       NegAcc, HasLane
     74   // fp scalar ops
     75   { ARM::VMLAS,       ARM::VMULS,       ARM::VADDS,      false,  false },
     76   { ARM::VMLSS,       ARM::VMULS,       ARM::VSUBS,      false,  false },
     77   { ARM::VMLAD,       ARM::VMULD,       ARM::VADDD,      false,  false },
     78   { ARM::VMLSD,       ARM::VMULD,       ARM::VSUBD,      false,  false },
     79   { ARM::VNMLAS,      ARM::VNMULS,      ARM::VSUBS,      true,   false },
     80   { ARM::VNMLSS,      ARM::VMULS,       ARM::VSUBS,      true,   false },
     81   { ARM::VNMLAD,      ARM::VNMULD,      ARM::VSUBD,      true,   false },
     82   { ARM::VNMLSD,      ARM::VMULD,       ARM::VSUBD,      true,   false },
     83 
     84   // fp SIMD ops
     85   { ARM::VMLAfd,      ARM::VMULfd,      ARM::VADDfd,     false,  false },
     86   { ARM::VMLSfd,      ARM::VMULfd,      ARM::VSUBfd,     false,  false },
     87   { ARM::VMLAfq,      ARM::VMULfq,      ARM::VADDfq,     false,  false },
     88   { ARM::VMLSfq,      ARM::VMULfq,      ARM::VSUBfq,     false,  false },
     89   { ARM::VMLAslfd,    ARM::VMULslfd,    ARM::VADDfd,     false,  true  },
     90   { ARM::VMLSslfd,    ARM::VMULslfd,    ARM::VSUBfd,     false,  true  },
     91   { ARM::VMLAslfq,    ARM::VMULslfq,    ARM::VADDfq,     false,  true  },
     92   { ARM::VMLSslfq,    ARM::VMULslfq,    ARM::VSUBfq,     false,  true  },
     93 };
     94 
     95 ARMBaseInstrInfo::ARMBaseInstrInfo(const ARMSubtarget& STI)
     96   : ARMGenInstrInfo(ARM::ADJCALLSTACKDOWN, ARM::ADJCALLSTACKUP),
     97     Subtarget(STI) {
     98   for (unsigned i = 0, e = array_lengthof(ARM_MLxTable); i != e; ++i) {
     99     if (!MLxEntryMap.insert(std::make_pair(ARM_MLxTable[i].MLxOpc, i)).second)
    100       llvm_unreachable("Duplicated entries?");
    101     MLxHazardOpcodes.insert(ARM_MLxTable[i].AddSubOpc);
    102     MLxHazardOpcodes.insert(ARM_MLxTable[i].MulOpc);
    103   }
    104 }
    105 
    106 // Use a ScoreboardHazardRecognizer for prepass ARM scheduling. TargetInstrImpl
    107 // currently defaults to no prepass hazard recognizer.
    108 ScheduleHazardRecognizer *
    109 ARMBaseInstrInfo::CreateTargetHazardRecognizer(const TargetSubtargetInfo *STI,
    110                                                const ScheduleDAG *DAG) const {
    111   if (usePreRAHazardRecognizer()) {
    112     const InstrItineraryData *II =
    113         static_cast<const ARMSubtarget *>(STI)->getInstrItineraryData();
    114     return new ScoreboardHazardRecognizer(II, DAG, "pre-RA-sched");
    115   }
    116   return TargetInstrInfo::CreateTargetHazardRecognizer(STI, DAG);
    117 }
    118 
    119 ScheduleHazardRecognizer *ARMBaseInstrInfo::
    120 CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II,
    121                                    const ScheduleDAG *DAG) const {
    122   if (Subtarget.isThumb2() || Subtarget.hasVFP2())
    123     return (ScheduleHazardRecognizer *)new ARMHazardRecognizer(II, DAG);
    124   return TargetInstrInfo::CreateTargetPostRAHazardRecognizer(II, DAG);
    125 }
    126 
    127 MachineInstr *
    128 ARMBaseInstrInfo::convertToThreeAddress(MachineFunction::iterator &MFI,
    129                                         MachineBasicBlock::iterator &MBBI,
    130                                         LiveVariables *LV) const {
    131   // FIXME: Thumb2 support.
    132 
    133   if (!EnableARM3Addr)
    134     return nullptr;
    135 
    136   MachineInstr *MI = MBBI;
    137   MachineFunction &MF = *MI->getParent()->getParent();
    138   uint64_t TSFlags = MI->getDesc().TSFlags;
    139   bool isPre = false;
    140   switch ((TSFlags & ARMII::IndexModeMask) >> ARMII::IndexModeShift) {
    141   default: return nullptr;
    142   case ARMII::IndexModePre:
    143     isPre = true;
    144     break;
    145   case ARMII::IndexModePost:
    146     break;
    147   }
    148 
    149   // Try splitting an indexed load/store to an un-indexed one plus an add/sub
    150   // operation.
    151   unsigned MemOpc = getUnindexedOpcode(MI->getOpcode());
    152   if (MemOpc == 0)
    153     return nullptr;
    154 
    155   MachineInstr *UpdateMI = nullptr;
    156   MachineInstr *MemMI = nullptr;
    157   unsigned AddrMode = (TSFlags & ARMII::AddrModeMask);
    158   const MCInstrDesc &MCID = MI->getDesc();
    159   unsigned NumOps = MCID.getNumOperands();
    160   bool isLoad = !MI->mayStore();
    161   const MachineOperand &WB = isLoad ? MI->getOperand(1) : MI->getOperand(0);
    162   const MachineOperand &Base = MI->getOperand(2);
    163   const MachineOperand &Offset = MI->getOperand(NumOps-3);
    164   unsigned WBReg = WB.getReg();
    165   unsigned BaseReg = Base.getReg();
    166   unsigned OffReg = Offset.getReg();
    167   unsigned OffImm = MI->getOperand(NumOps-2).getImm();
    168   ARMCC::CondCodes Pred = (ARMCC::CondCodes)MI->getOperand(NumOps-1).getImm();
    169   switch (AddrMode) {
    170   default: llvm_unreachable("Unknown indexed op!");
    171   case ARMII::AddrMode2: {
    172     bool isSub = ARM_AM::getAM2Op(OffImm) == ARM_AM::sub;
    173     unsigned Amt = ARM_AM::getAM2Offset(OffImm);
    174     if (OffReg == 0) {
    175       if (ARM_AM::getSOImmVal(Amt) == -1)
    176         // Can't encode it in a so_imm operand. This transformation will
    177         // add more than 1 instruction. Abandon!
    178         return nullptr;
    179       UpdateMI = BuildMI(MF, MI->getDebugLoc(),
    180                          get(isSub ? ARM::SUBri : ARM::ADDri), WBReg)
    181         .addReg(BaseReg).addImm(Amt)
    182         .addImm(Pred).addReg(0).addReg(0);
    183     } else if (Amt != 0) {
    184       ARM_AM::ShiftOpc ShOpc = ARM_AM::getAM2ShiftOpc(OffImm);
    185       unsigned SOOpc = ARM_AM::getSORegOpc(ShOpc, Amt);
    186       UpdateMI = BuildMI(MF, MI->getDebugLoc(),
    187                          get(isSub ? ARM::SUBrsi : ARM::ADDrsi), WBReg)
    188         .addReg(BaseReg).addReg(OffReg).addReg(0).addImm(SOOpc)
    189         .addImm(Pred).addReg(0).addReg(0);
    190     } else
    191       UpdateMI = BuildMI(MF, MI->getDebugLoc(),
    192                          get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg)
    193         .addReg(BaseReg).addReg(OffReg)
    194         .addImm(Pred).addReg(0).addReg(0);
    195     break;
    196   }
    197   case ARMII::AddrMode3 : {
    198     bool isSub = ARM_AM::getAM3Op(OffImm) == ARM_AM::sub;
    199     unsigned Amt = ARM_AM::getAM3Offset(OffImm);
    200     if (OffReg == 0)
    201       // Immediate is 8-bits. It's guaranteed to fit in a so_imm operand.
    202       UpdateMI = BuildMI(MF, MI->getDebugLoc(),
    203                          get(isSub ? ARM::SUBri : ARM::ADDri), WBReg)
    204         .addReg(BaseReg).addImm(Amt)
    205         .addImm(Pred).addReg(0).addReg(0);
    206     else
    207       UpdateMI = BuildMI(MF, MI->getDebugLoc(),
    208                          get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg)
    209         .addReg(BaseReg).addReg(OffReg)
    210         .addImm(Pred).addReg(0).addReg(0);
    211     break;
    212   }
    213   }
    214 
    215   std::vector<MachineInstr*> NewMIs;
    216   if (isPre) {
    217     if (isLoad)
    218       MemMI = BuildMI(MF, MI->getDebugLoc(),
    219                       get(MemOpc), MI->getOperand(0).getReg())
    220         .addReg(WBReg).addImm(0).addImm(Pred);
    221     else
    222       MemMI = BuildMI(MF, MI->getDebugLoc(),
    223                       get(MemOpc)).addReg(MI->getOperand(1).getReg())
    224         .addReg(WBReg).addReg(0).addImm(0).addImm(Pred);
    225     NewMIs.push_back(MemMI);
    226     NewMIs.push_back(UpdateMI);
    227   } else {
    228     if (isLoad)
    229       MemMI = BuildMI(MF, MI->getDebugLoc(),
    230                       get(MemOpc), MI->getOperand(0).getReg())
    231         .addReg(BaseReg).addImm(0).addImm(Pred);
    232     else
    233       MemMI = BuildMI(MF, MI->getDebugLoc(),
    234                       get(MemOpc)).addReg(MI->getOperand(1).getReg())
    235         .addReg(BaseReg).addReg(0).addImm(0).addImm(Pred);
    236     if (WB.isDead())
    237       UpdateMI->getOperand(0).setIsDead();
    238     NewMIs.push_back(UpdateMI);
    239     NewMIs.push_back(MemMI);
    240   }
    241 
    242   // Transfer LiveVariables states, kill / dead info.
    243   if (LV) {
    244     for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
    245       MachineOperand &MO = MI->getOperand(i);
    246       if (MO.isReg() && TargetRegisterInfo::isVirtualRegister(MO.getReg())) {
    247         unsigned Reg = MO.getReg();
    248 
    249         LiveVariables::VarInfo &VI = LV->getVarInfo(Reg);
    250         if (MO.isDef()) {
    251           MachineInstr *NewMI = (Reg == WBReg) ? UpdateMI : MemMI;
    252           if (MO.isDead())
    253             LV->addVirtualRegisterDead(Reg, NewMI);
    254         }
    255         if (MO.isUse() && MO.isKill()) {
    256           for (unsigned j = 0; j < 2; ++j) {
    257             // Look at the two new MI's in reverse order.
    258             MachineInstr *NewMI = NewMIs[j];
    259             if (!NewMI->readsRegister(Reg))
    260               continue;
    261             LV->addVirtualRegisterKilled(Reg, NewMI);
    262             if (VI.removeKill(MI))
    263               VI.Kills.push_back(NewMI);
    264             break;
    265           }
    266         }
    267       }
    268     }
    269   }
    270 
    271   MFI->insert(MBBI, NewMIs[1]);
    272   MFI->insert(MBBI, NewMIs[0]);
    273   return NewMIs[0];
    274 }
    275 
    276 // Branch analysis.
    277 bool
    278 ARMBaseInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB,
    279                                 MachineBasicBlock *&FBB,
    280                                 SmallVectorImpl<MachineOperand> &Cond,
    281                                 bool AllowModify) const {
    282   TBB = nullptr;
    283   FBB = nullptr;
    284 
    285   MachineBasicBlock::iterator I = MBB.end();
    286   if (I == MBB.begin())
    287     return false; // Empty blocks are easy.
    288   --I;
    289 
    290   // Walk backwards from the end of the basic block until the branch is
    291   // analyzed or we give up.
    292   while (isPredicated(I) || I->isTerminator() || I->isDebugValue()) {
    293 
    294     // Flag to be raised on unanalyzeable instructions. This is useful in cases
    295     // where we want to clean up on the end of the basic block before we bail
    296     // out.
    297     bool CantAnalyze = false;
    298 
    299     // Skip over DEBUG values and predicated nonterminators.
    300     while (I->isDebugValue() || !I->isTerminator()) {
    301       if (I == MBB.begin())
    302         return false;
    303       --I;
    304     }
    305 
    306     if (isIndirectBranchOpcode(I->getOpcode()) ||
    307         isJumpTableBranchOpcode(I->getOpcode())) {
    308       // Indirect branches and jump tables can't be analyzed, but we still want
    309       // to clean up any instructions at the tail of the basic block.
    310       CantAnalyze = true;
    311     } else if (isUncondBranchOpcode(I->getOpcode())) {
    312       TBB = I->getOperand(0).getMBB();
    313     } else if (isCondBranchOpcode(I->getOpcode())) {
    314       // Bail out if we encounter multiple conditional branches.
    315       if (!Cond.empty())
    316         return true;
    317 
    318       assert(!FBB && "FBB should have been null.");
    319       FBB = TBB;
    320       TBB = I->getOperand(0).getMBB();
    321       Cond.push_back(I->getOperand(1));
    322       Cond.push_back(I->getOperand(2));
    323     } else if (I->isReturn()) {
    324       // Returns can't be analyzed, but we should run cleanup.
    325       CantAnalyze = !isPredicated(I);
    326     } else {
    327       // We encountered other unrecognized terminator. Bail out immediately.
    328       return true;
    329     }
    330 
    331     // Cleanup code - to be run for unpredicated unconditional branches and
    332     //                returns.
    333     if (!isPredicated(I) &&
    334           (isUncondBranchOpcode(I->getOpcode()) ||
    335            isIndirectBranchOpcode(I->getOpcode()) ||
    336            isJumpTableBranchOpcode(I->getOpcode()) ||
    337            I->isReturn())) {
    338       // Forget any previous condition branch information - it no longer applies.
    339       Cond.clear();
    340       FBB = nullptr;
    341 
    342       // If we can modify the function, delete everything below this
    343       // unconditional branch.
    344       if (AllowModify) {
    345         MachineBasicBlock::iterator DI = std::next(I);
    346         while (DI != MBB.end()) {
    347           MachineInstr *InstToDelete = DI;
    348           ++DI;
    349           InstToDelete->eraseFromParent();
    350         }
    351       }
    352     }
    353 
    354     if (CantAnalyze)
    355       return true;
    356 
    357     if (I == MBB.begin())
    358       return false;
    359 
    360     --I;
    361   }
    362 
    363   // We made it past the terminators without bailing out - we must have
    364   // analyzed this branch successfully.
    365   return false;
    366 }
    367 
    368 
    369 unsigned ARMBaseInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const {
    370   MachineBasicBlock::iterator I = MBB.getLastNonDebugInstr();
    371   if (I == MBB.end())
    372     return 0;
    373 
    374   if (!isUncondBranchOpcode(I->getOpcode()) &&
    375       !isCondBranchOpcode(I->getOpcode()))
    376     return 0;
    377 
    378   // Remove the branch.
    379   I->eraseFromParent();
    380 
    381   I = MBB.end();
    382 
    383   if (I == MBB.begin()) return 1;
    384   --I;
    385   if (!isCondBranchOpcode(I->getOpcode()))
    386     return 1;
    387 
    388   // Remove the branch.
    389   I->eraseFromParent();
    390   return 2;
    391 }
    392 
    393 unsigned
    394 ARMBaseInstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
    395                                MachineBasicBlock *FBB,
    396                                ArrayRef<MachineOperand> Cond,
    397                                DebugLoc DL) const {
    398   ARMFunctionInfo *AFI = MBB.getParent()->getInfo<ARMFunctionInfo>();
    399   int BOpc   = !AFI->isThumbFunction()
    400     ? ARM::B : (AFI->isThumb2Function() ? ARM::t2B : ARM::tB);
    401   int BccOpc = !AFI->isThumbFunction()
    402     ? ARM::Bcc : (AFI->isThumb2Function() ? ARM::t2Bcc : ARM::tBcc);
    403   bool isThumb = AFI->isThumbFunction() || AFI->isThumb2Function();
    404 
    405   // Shouldn't be a fall through.
    406   assert(TBB && "InsertBranch must not be told to insert a fallthrough");
    407   assert((Cond.size() == 2 || Cond.size() == 0) &&
    408          "ARM branch conditions have two components!");
    409 
    410   // For conditional branches, we use addOperand to preserve CPSR flags.
    411 
    412   if (!FBB) {
    413     if (Cond.empty()) { // Unconditional branch?
    414       if (isThumb)
    415         BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB).addImm(ARMCC::AL).addReg(0);
    416       else
    417         BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB);
    418     } else
    419       BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB)
    420         .addImm(Cond[0].getImm()).addOperand(Cond[1]);
    421     return 1;
    422   }
    423 
    424   // Two-way conditional branch.
    425   BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB)
    426     .addImm(Cond[0].getImm()).addOperand(Cond[1]);
    427   if (isThumb)
    428     BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB).addImm(ARMCC::AL).addReg(0);
    429   else
    430     BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB);
    431   return 2;
    432 }
    433 
    434 bool ARMBaseInstrInfo::
    435 ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const {
    436   ARMCC::CondCodes CC = (ARMCC::CondCodes)(int)Cond[0].getImm();
    437   Cond[0].setImm(ARMCC::getOppositeCondition(CC));
    438   return false;
    439 }
    440 
    441 bool ARMBaseInstrInfo::isPredicated(const MachineInstr *MI) const {
    442   if (MI->isBundle()) {
    443     MachineBasicBlock::const_instr_iterator I = MI->getIterator();
    444     MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
    445     while (++I != E && I->isInsideBundle()) {
    446       int PIdx = I->findFirstPredOperandIdx();
    447       if (PIdx != -1 && I->getOperand(PIdx).getImm() != ARMCC::AL)
    448         return true;
    449     }
    450     return false;
    451   }
    452 
    453   int PIdx = MI->findFirstPredOperandIdx();
    454   return PIdx != -1 && MI->getOperand(PIdx).getImm() != ARMCC::AL;
    455 }
    456 
    457 bool ARMBaseInstrInfo::
    458 PredicateInstruction(MachineInstr *MI, ArrayRef<MachineOperand> Pred) const {
    459   unsigned Opc = MI->getOpcode();
    460   if (isUncondBranchOpcode(Opc)) {
    461     MI->setDesc(get(getMatchingCondBranchOpcode(Opc)));
    462     MachineInstrBuilder(*MI->getParent()->getParent(), MI)
    463       .addImm(Pred[0].getImm())
    464       .addReg(Pred[1].getReg());
    465     return true;
    466   }
    467 
    468   int PIdx = MI->findFirstPredOperandIdx();
    469   if (PIdx != -1) {
    470     MachineOperand &PMO = MI->getOperand(PIdx);
    471     PMO.setImm(Pred[0].getImm());
    472     MI->getOperand(PIdx+1).setReg(Pred[1].getReg());
    473     return true;
    474   }
    475   return false;
    476 }
    477 
    478 bool ARMBaseInstrInfo::SubsumesPredicate(ArrayRef<MachineOperand> Pred1,
    479                                          ArrayRef<MachineOperand> Pred2) const {
    480   if (Pred1.size() > 2 || Pred2.size() > 2)
    481     return false;
    482 
    483   ARMCC::CondCodes CC1 = (ARMCC::CondCodes)Pred1[0].getImm();
    484   ARMCC::CondCodes CC2 = (ARMCC::CondCodes)Pred2[0].getImm();
    485   if (CC1 == CC2)
    486     return true;
    487 
    488   switch (CC1) {
    489   default:
    490     return false;
    491   case ARMCC::AL:
    492     return true;
    493   case ARMCC::HS:
    494     return CC2 == ARMCC::HI;
    495   case ARMCC::LS:
    496     return CC2 == ARMCC::LO || CC2 == ARMCC::EQ;
    497   case ARMCC::GE:
    498     return CC2 == ARMCC::GT;
    499   case ARMCC::LE:
    500     return CC2 == ARMCC::LT;
    501   }
    502 }
    503 
    504 bool ARMBaseInstrInfo::DefinesPredicate(MachineInstr *MI,
    505                                     std::vector<MachineOperand> &Pred) const {
    506   bool Found = false;
    507   for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
    508     const MachineOperand &MO = MI->getOperand(i);
    509     if ((MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) ||
    510         (MO.isReg() && MO.isDef() && MO.getReg() == ARM::CPSR)) {
    511       Pred.push_back(MO);
    512       Found = true;
    513     }
    514   }
    515 
    516   return Found;
    517 }
    518 
    519 static bool isCPSRDefined(const MachineInstr *MI) {
    520   for (const auto &MO : MI->operands())
    521     if (MO.isReg() && MO.getReg() == ARM::CPSR && MO.isDef() && !MO.isDead())
    522       return true;
    523   return false;
    524 }
    525 
    526 static bool isEligibleForITBlock(const MachineInstr *MI) {
    527   switch (MI->getOpcode()) {
    528   default: return true;
    529   case ARM::tADC:   // ADC (register) T1
    530   case ARM::tADDi3: // ADD (immediate) T1
    531   case ARM::tADDi8: // ADD (immediate) T2
    532   case ARM::tADDrr: // ADD (register) T1
    533   case ARM::tAND:   // AND (register) T1
    534   case ARM::tASRri: // ASR (immediate) T1
    535   case ARM::tASRrr: // ASR (register) T1
    536   case ARM::tBIC:   // BIC (register) T1
    537   case ARM::tEOR:   // EOR (register) T1
    538   case ARM::tLSLri: // LSL (immediate) T1
    539   case ARM::tLSLrr: // LSL (register) T1
    540   case ARM::tLSRri: // LSR (immediate) T1
    541   case ARM::tLSRrr: // LSR (register) T1
    542   case ARM::tMUL:   // MUL T1
    543   case ARM::tMVN:   // MVN (register) T1
    544   case ARM::tORR:   // ORR (register) T1
    545   case ARM::tROR:   // ROR (register) T1
    546   case ARM::tRSB:   // RSB (immediate) T1
    547   case ARM::tSBC:   // SBC (register) T1
    548   case ARM::tSUBi3: // SUB (immediate) T1
    549   case ARM::tSUBi8: // SUB (immediate) T2
    550   case ARM::tSUBrr: // SUB (register) T1
    551     return !isCPSRDefined(MI);
    552   }
    553 }
    554 
    555 /// isPredicable - Return true if the specified instruction can be predicated.
    556 /// By default, this returns true for every instruction with a
    557 /// PredicateOperand.
    558 bool ARMBaseInstrInfo::isPredicable(MachineInstr *MI) const {
    559   if (!MI->isPredicable())
    560     return false;
    561 
    562   if (!isEligibleForITBlock(MI))
    563     return false;
    564 
    565   ARMFunctionInfo *AFI =
    566     MI->getParent()->getParent()->getInfo<ARMFunctionInfo>();
    567 
    568   if (AFI->isThumb2Function()) {
    569     if (getSubtarget().restrictIT())
    570       return isV8EligibleForIT(MI);
    571   } else { // non-Thumb
    572     if ((MI->getDesc().TSFlags & ARMII::DomainMask) == ARMII::DomainNEON)
    573       return false;
    574   }
    575 
    576   return true;
    577 }
    578 
    579 namespace llvm {
    580 template <> bool IsCPSRDead<MachineInstr>(MachineInstr *MI) {
    581   for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
    582     const MachineOperand &MO = MI->getOperand(i);
    583     if (!MO.isReg() || MO.isUndef() || MO.isUse())
    584       continue;
    585     if (MO.getReg() != ARM::CPSR)
    586       continue;
    587     if (!MO.isDead())
    588       return false;
    589   }
    590   // all definitions of CPSR are dead
    591   return true;
    592 }
    593 }
    594 
    595 /// GetInstSize - Return the size of the specified MachineInstr.
    596 ///
    597 unsigned ARMBaseInstrInfo::GetInstSizeInBytes(const MachineInstr *MI) const {
    598   const MachineBasicBlock &MBB = *MI->getParent();
    599   const MachineFunction *MF = MBB.getParent();
    600   const MCAsmInfo *MAI = MF->getTarget().getMCAsmInfo();
    601 
    602   const MCInstrDesc &MCID = MI->getDesc();
    603   if (MCID.getSize())
    604     return MCID.getSize();
    605 
    606   // If this machine instr is an inline asm, measure it.
    607   if (MI->getOpcode() == ARM::INLINEASM)
    608     return getInlineAsmLength(MI->getOperand(0).getSymbolName(), *MAI);
    609   unsigned Opc = MI->getOpcode();
    610   switch (Opc) {
    611   default:
    612     // pseudo-instruction sizes are zero.
    613     return 0;
    614   case TargetOpcode::BUNDLE:
    615     return getInstBundleLength(MI);
    616   case ARM::MOVi16_ga_pcrel:
    617   case ARM::MOVTi16_ga_pcrel:
    618   case ARM::t2MOVi16_ga_pcrel:
    619   case ARM::t2MOVTi16_ga_pcrel:
    620     return 4;
    621   case ARM::MOVi32imm:
    622   case ARM::t2MOVi32imm:
    623     return 8;
    624   case ARM::CONSTPOOL_ENTRY:
    625   case ARM::JUMPTABLE_INSTS:
    626   case ARM::JUMPTABLE_ADDRS:
    627   case ARM::JUMPTABLE_TBB:
    628   case ARM::JUMPTABLE_TBH:
    629     // If this machine instr is a constant pool entry, its size is recorded as
    630     // operand #2.
    631     return MI->getOperand(2).getImm();
    632   case ARM::Int_eh_sjlj_longjmp:
    633     return 16;
    634   case ARM::tInt_eh_sjlj_longjmp:
    635     return 10;
    636   case ARM::Int_eh_sjlj_setjmp:
    637   case ARM::Int_eh_sjlj_setjmp_nofp:
    638     return 20;
    639   case ARM::tInt_eh_sjlj_setjmp:
    640   case ARM::t2Int_eh_sjlj_setjmp:
    641   case ARM::t2Int_eh_sjlj_setjmp_nofp:
    642     return 12;
    643   case ARM::SPACE:
    644     return MI->getOperand(1).getImm();
    645   }
    646 }
    647 
    648 unsigned ARMBaseInstrInfo::getInstBundleLength(const MachineInstr *MI) const {
    649   unsigned Size = 0;
    650   MachineBasicBlock::const_instr_iterator I = MI->getIterator();
    651   MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
    652   while (++I != E && I->isInsideBundle()) {
    653     assert(!I->isBundle() && "No nested bundle!");
    654     Size += GetInstSizeInBytes(&*I);
    655   }
    656   return Size;
    657 }
    658 
    659 void ARMBaseInstrInfo::copyFromCPSR(MachineBasicBlock &MBB,
    660                                     MachineBasicBlock::iterator I,
    661                                     unsigned DestReg, bool KillSrc,
    662                                     const ARMSubtarget &Subtarget) const {
    663   unsigned Opc = Subtarget.isThumb()
    664                      ? (Subtarget.isMClass() ? ARM::t2MRS_M : ARM::t2MRS_AR)
    665                      : ARM::MRS;
    666 
    667   MachineInstrBuilder MIB =
    668       BuildMI(MBB, I, I->getDebugLoc(), get(Opc), DestReg);
    669 
    670   // There is only 1 A/R class MRS instruction, and it always refers to
    671   // APSR. However, there are lots of other possibilities on M-class cores.
    672   if (Subtarget.isMClass())
    673     MIB.addImm(0x800);
    674 
    675   AddDefaultPred(MIB);
    676 
    677   MIB.addReg(ARM::CPSR, RegState::Implicit | getKillRegState(KillSrc));
    678 }
    679 
    680 void ARMBaseInstrInfo::copyToCPSR(MachineBasicBlock &MBB,
    681                                   MachineBasicBlock::iterator I,
    682                                   unsigned SrcReg, bool KillSrc,
    683                                   const ARMSubtarget &Subtarget) const {
    684   unsigned Opc = Subtarget.isThumb()
    685                      ? (Subtarget.isMClass() ? ARM::t2MSR_M : ARM::t2MSR_AR)
    686                      : ARM::MSR;
    687 
    688   MachineInstrBuilder MIB = BuildMI(MBB, I, I->getDebugLoc(), get(Opc));
    689 
    690   if (Subtarget.isMClass())
    691     MIB.addImm(0x800);
    692   else
    693     MIB.addImm(8);
    694 
    695   MIB.addReg(SrcReg, getKillRegState(KillSrc));
    696 
    697   AddDefaultPred(MIB);
    698 
    699   MIB.addReg(ARM::CPSR, RegState::Implicit | RegState::Define);
    700 }
    701 
    702 void ARMBaseInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
    703                                    MachineBasicBlock::iterator I, DebugLoc DL,
    704                                    unsigned DestReg, unsigned SrcReg,
    705                                    bool KillSrc) const {
    706   bool GPRDest = ARM::GPRRegClass.contains(DestReg);
    707   bool GPRSrc = ARM::GPRRegClass.contains(SrcReg);
    708 
    709   if (GPRDest && GPRSrc) {
    710     AddDefaultCC(AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::MOVr), DestReg)
    711                                     .addReg(SrcReg, getKillRegState(KillSrc))));
    712     return;
    713   }
    714 
    715   bool SPRDest = ARM::SPRRegClass.contains(DestReg);
    716   bool SPRSrc = ARM::SPRRegClass.contains(SrcReg);
    717 
    718   unsigned Opc = 0;
    719   if (SPRDest && SPRSrc)
    720     Opc = ARM::VMOVS;
    721   else if (GPRDest && SPRSrc)
    722     Opc = ARM::VMOVRS;
    723   else if (SPRDest && GPRSrc)
    724     Opc = ARM::VMOVSR;
    725   else if (ARM::DPRRegClass.contains(DestReg, SrcReg) && !Subtarget.isFPOnlySP())
    726     Opc = ARM::VMOVD;
    727   else if (ARM::QPRRegClass.contains(DestReg, SrcReg))
    728     Opc = ARM::VORRq;
    729 
    730   if (Opc) {
    731     MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(Opc), DestReg);
    732     MIB.addReg(SrcReg, getKillRegState(KillSrc));
    733     if (Opc == ARM::VORRq)
    734       MIB.addReg(SrcReg, getKillRegState(KillSrc));
    735     AddDefaultPred(MIB);
    736     return;
    737   }
    738 
    739   // Handle register classes that require multiple instructions.
    740   unsigned BeginIdx = 0;
    741   unsigned SubRegs = 0;
    742   int Spacing = 1;
    743 
    744   // Use VORRq when possible.
    745   if (ARM::QQPRRegClass.contains(DestReg, SrcReg)) {
    746     Opc = ARM::VORRq;
    747     BeginIdx = ARM::qsub_0;
    748     SubRegs = 2;
    749   } else if (ARM::QQQQPRRegClass.contains(DestReg, SrcReg)) {
    750     Opc = ARM::VORRq;
    751     BeginIdx = ARM::qsub_0;
    752     SubRegs = 4;
    753   // Fall back to VMOVD.
    754   } else if (ARM::DPairRegClass.contains(DestReg, SrcReg)) {
    755     Opc = ARM::VMOVD;
    756     BeginIdx = ARM::dsub_0;
    757     SubRegs = 2;
    758   } else if (ARM::DTripleRegClass.contains(DestReg, SrcReg)) {
    759     Opc = ARM::VMOVD;
    760     BeginIdx = ARM::dsub_0;
    761     SubRegs = 3;
    762   } else if (ARM::DQuadRegClass.contains(DestReg, SrcReg)) {
    763     Opc = ARM::VMOVD;
    764     BeginIdx = ARM::dsub_0;
    765     SubRegs = 4;
    766   } else if (ARM::GPRPairRegClass.contains(DestReg, SrcReg)) {
    767     Opc = Subtarget.isThumb2() ? ARM::tMOVr : ARM::MOVr;
    768     BeginIdx = ARM::gsub_0;
    769     SubRegs = 2;
    770   } else if (ARM::DPairSpcRegClass.contains(DestReg, SrcReg)) {
    771     Opc = ARM::VMOVD;
    772     BeginIdx = ARM::dsub_0;
    773     SubRegs = 2;
    774     Spacing = 2;
    775   } else if (ARM::DTripleSpcRegClass.contains(DestReg, SrcReg)) {
    776     Opc = ARM::VMOVD;
    777     BeginIdx = ARM::dsub_0;
    778     SubRegs = 3;
    779     Spacing = 2;
    780   } else if (ARM::DQuadSpcRegClass.contains(DestReg, SrcReg)) {
    781     Opc = ARM::VMOVD;
    782     BeginIdx = ARM::dsub_0;
    783     SubRegs = 4;
    784     Spacing = 2;
    785   } else if (ARM::DPRRegClass.contains(DestReg, SrcReg) && Subtarget.isFPOnlySP()) {
    786     Opc = ARM::VMOVS;
    787     BeginIdx = ARM::ssub_0;
    788     SubRegs = 2;
    789   } else if (SrcReg == ARM::CPSR) {
    790     copyFromCPSR(MBB, I, DestReg, KillSrc, Subtarget);
    791     return;
    792   } else if (DestReg == ARM::CPSR) {
    793     copyToCPSR(MBB, I, SrcReg, KillSrc, Subtarget);
    794     return;
    795   }
    796 
    797   assert(Opc && "Impossible reg-to-reg copy");
    798 
    799   const TargetRegisterInfo *TRI = &getRegisterInfo();
    800   MachineInstrBuilder Mov;
    801 
    802   // Copy register tuples backward when the first Dest reg overlaps with SrcReg.
    803   if (TRI->regsOverlap(SrcReg, TRI->getSubReg(DestReg, BeginIdx))) {
    804     BeginIdx = BeginIdx + ((SubRegs - 1) * Spacing);
    805     Spacing = -Spacing;
    806   }
    807 #ifndef NDEBUG
    808   SmallSet<unsigned, 4> DstRegs;
    809 #endif
    810   for (unsigned i = 0; i != SubRegs; ++i) {
    811     unsigned Dst = TRI->getSubReg(DestReg, BeginIdx + i * Spacing);
    812     unsigned Src = TRI->getSubReg(SrcReg, BeginIdx + i * Spacing);
    813     assert(Dst && Src && "Bad sub-register");
    814 #ifndef NDEBUG
    815     assert(!DstRegs.count(Src) && "destructive vector copy");
    816     DstRegs.insert(Dst);
    817 #endif
    818     Mov = BuildMI(MBB, I, I->getDebugLoc(), get(Opc), Dst).addReg(Src);
    819     // VORR takes two source operands.
    820     if (Opc == ARM::VORRq)
    821       Mov.addReg(Src);
    822     Mov = AddDefaultPred(Mov);
    823     // MOVr can set CC.
    824     if (Opc == ARM::MOVr)
    825       Mov = AddDefaultCC(Mov);
    826   }
    827   // Add implicit super-register defs and kills to the last instruction.
    828   Mov->addRegisterDefined(DestReg, TRI);
    829   if (KillSrc)
    830     Mov->addRegisterKilled(SrcReg, TRI);
    831 }
    832 
    833 const MachineInstrBuilder &
    834 ARMBaseInstrInfo::AddDReg(MachineInstrBuilder &MIB, unsigned Reg,
    835                           unsigned SubIdx, unsigned State,
    836                           const TargetRegisterInfo *TRI) const {
    837   if (!SubIdx)
    838     return MIB.addReg(Reg, State);
    839 
    840   if (TargetRegisterInfo::isPhysicalRegister(Reg))
    841     return MIB.addReg(TRI->getSubReg(Reg, SubIdx), State);
    842   return MIB.addReg(Reg, State, SubIdx);
    843 }
    844 
    845 void ARMBaseInstrInfo::
    846 storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
    847                     unsigned SrcReg, bool isKill, int FI,
    848                     const TargetRegisterClass *RC,
    849                     const TargetRegisterInfo *TRI) const {
    850   DebugLoc DL;
    851   if (I != MBB.end()) DL = I->getDebugLoc();
    852   MachineFunction &MF = *MBB.getParent();
    853   MachineFrameInfo &MFI = *MF.getFrameInfo();
    854   unsigned Align = MFI.getObjectAlignment(FI);
    855 
    856   MachineMemOperand *MMO = MF.getMachineMemOperand(
    857       MachinePointerInfo::getFixedStack(MF, FI), MachineMemOperand::MOStore,
    858       MFI.getObjectSize(FI), Align);
    859 
    860   switch (RC->getSize()) {
    861     case 4:
    862       if (ARM::GPRRegClass.hasSubClassEq(RC)) {
    863         AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STRi12))
    864                    .addReg(SrcReg, getKillRegState(isKill))
    865                    .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
    866       } else if (ARM::SPRRegClass.hasSubClassEq(RC)) {
    867         AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRS))
    868                    .addReg(SrcReg, getKillRegState(isKill))
    869                    .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
    870       } else
    871         llvm_unreachable("Unknown reg class!");
    872       break;
    873     case 8:
    874       if (ARM::DPRRegClass.hasSubClassEq(RC)) {
    875         AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRD))
    876                    .addReg(SrcReg, getKillRegState(isKill))
    877                    .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
    878       } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) {
    879         if (Subtarget.hasV5TEOps()) {
    880           MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(ARM::STRD));
    881           AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI);
    882           AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI);
    883           MIB.addFrameIndex(FI).addReg(0).addImm(0).addMemOperand(MMO);
    884 
    885           AddDefaultPred(MIB);
    886         } else {
    887           // Fallback to STM instruction, which has existed since the dawn of
    888           // time.
    889           MachineInstrBuilder MIB =
    890             AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STMIA))
    891                              .addFrameIndex(FI).addMemOperand(MMO));
    892           AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI);
    893           AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI);
    894         }
    895       } else
    896         llvm_unreachable("Unknown reg class!");
    897       break;
    898     case 16:
    899       if (ARM::DPairRegClass.hasSubClassEq(RC)) {
    900         // Use aligned spills if the stack can be realigned.
    901         if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
    902           AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1q64))
    903                      .addFrameIndex(FI).addImm(16)
    904                      .addReg(SrcReg, getKillRegState(isKill))
    905                      .addMemOperand(MMO));
    906         } else {
    907           AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMQIA))
    908                      .addReg(SrcReg, getKillRegState(isKill))
    909                      .addFrameIndex(FI)
    910                      .addMemOperand(MMO));
    911         }
    912       } else
    913         llvm_unreachable("Unknown reg class!");
    914       break;
    915     case 24:
    916       if (ARM::DTripleRegClass.hasSubClassEq(RC)) {
    917         // Use aligned spills if the stack can be realigned.
    918         if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
    919           AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64TPseudo))
    920                      .addFrameIndex(FI).addImm(16)
    921                      .addReg(SrcReg, getKillRegState(isKill))
    922                      .addMemOperand(MMO));
    923         } else {
    924           MachineInstrBuilder MIB =
    925           AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA))
    926                        .addFrameIndex(FI))
    927                        .addMemOperand(MMO);
    928           MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI);
    929           MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI);
    930           AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI);
    931         }
    932       } else
    933         llvm_unreachable("Unknown reg class!");
    934       break;
    935     case 32:
    936       if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) {
    937         if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
    938           // FIXME: It's possible to only store part of the QQ register if the
    939           // spilled def has a sub-register index.
    940           AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64QPseudo))
    941                      .addFrameIndex(FI).addImm(16)
    942                      .addReg(SrcReg, getKillRegState(isKill))
    943                      .addMemOperand(MMO));
    944         } else {
    945           MachineInstrBuilder MIB =
    946           AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA))
    947                        .addFrameIndex(FI))
    948                        .addMemOperand(MMO);
    949           MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI);
    950           MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI);
    951           MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI);
    952                 AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI);
    953         }
    954       } else
    955         llvm_unreachable("Unknown reg class!");
    956       break;
    957     case 64:
    958       if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) {
    959         MachineInstrBuilder MIB =
    960           AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA))
    961                          .addFrameIndex(FI))
    962                          .addMemOperand(MMO);
    963         MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI);
    964         MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI);
    965         MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI);
    966         MIB = AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI);
    967         MIB = AddDReg(MIB, SrcReg, ARM::dsub_4, 0, TRI);
    968         MIB = AddDReg(MIB, SrcReg, ARM::dsub_5, 0, TRI);
    969         MIB = AddDReg(MIB, SrcReg, ARM::dsub_6, 0, TRI);
    970               AddDReg(MIB, SrcReg, ARM::dsub_7, 0, TRI);
    971       } else
    972         llvm_unreachable("Unknown reg class!");
    973       break;
    974     default:
    975       llvm_unreachable("Unknown reg class!");
    976   }
    977 }
    978 
    979 unsigned
    980 ARMBaseInstrInfo::isStoreToStackSlot(const MachineInstr *MI,
    981                                      int &FrameIndex) const {
    982   switch (MI->getOpcode()) {
    983   default: break;
    984   case ARM::STRrs:
    985   case ARM::t2STRs: // FIXME: don't use t2STRs to access frame.
    986     if (MI->getOperand(1).isFI() &&
    987         MI->getOperand(2).isReg() &&
    988         MI->getOperand(3).isImm() &&
    989         MI->getOperand(2).getReg() == 0 &&
    990         MI->getOperand(3).getImm() == 0) {
    991       FrameIndex = MI->getOperand(1).getIndex();
    992       return MI->getOperand(0).getReg();
    993     }
    994     break;
    995   case ARM::STRi12:
    996   case ARM::t2STRi12:
    997   case ARM::tSTRspi:
    998   case ARM::VSTRD:
    999   case ARM::VSTRS:
   1000     if (MI->getOperand(1).isFI() &&
   1001         MI->getOperand(2).isImm() &&
   1002         MI->getOperand(2).getImm() == 0) {
   1003       FrameIndex = MI->getOperand(1).getIndex();
   1004       return MI->getOperand(0).getReg();
   1005     }
   1006     break;
   1007   case ARM::VST1q64:
   1008   case ARM::VST1d64TPseudo:
   1009   case ARM::VST1d64QPseudo:
   1010     if (MI->getOperand(0).isFI() &&
   1011         MI->getOperand(2).getSubReg() == 0) {
   1012       FrameIndex = MI->getOperand(0).getIndex();
   1013       return MI->getOperand(2).getReg();
   1014     }
   1015     break;
   1016   case ARM::VSTMQIA:
   1017     if (MI->getOperand(1).isFI() &&
   1018         MI->getOperand(0).getSubReg() == 0) {
   1019       FrameIndex = MI->getOperand(1).getIndex();
   1020       return MI->getOperand(0).getReg();
   1021     }
   1022     break;
   1023   }
   1024 
   1025   return 0;
   1026 }
   1027 
   1028 unsigned ARMBaseInstrInfo::isStoreToStackSlotPostFE(const MachineInstr *MI,
   1029                                                     int &FrameIndex) const {
   1030   const MachineMemOperand *Dummy;
   1031   return MI->mayStore() && hasStoreToStackSlot(MI, Dummy, FrameIndex);
   1032 }
   1033 
   1034 void ARMBaseInstrInfo::
   1035 loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
   1036                      unsigned DestReg, int FI,
   1037                      const TargetRegisterClass *RC,
   1038                      const TargetRegisterInfo *TRI) const {
   1039   DebugLoc DL;
   1040   if (I != MBB.end()) DL = I->getDebugLoc();
   1041   MachineFunction &MF = *MBB.getParent();
   1042   MachineFrameInfo &MFI = *MF.getFrameInfo();
   1043   unsigned Align = MFI.getObjectAlignment(FI);
   1044   MachineMemOperand *MMO = MF.getMachineMemOperand(
   1045       MachinePointerInfo::getFixedStack(MF, FI), MachineMemOperand::MOLoad,
   1046       MFI.getObjectSize(FI), Align);
   1047 
   1048   switch (RC->getSize()) {
   1049   case 4:
   1050     if (ARM::GPRRegClass.hasSubClassEq(RC)) {
   1051       AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::LDRi12), DestReg)
   1052                    .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
   1053 
   1054     } else if (ARM::SPRRegClass.hasSubClassEq(RC)) {
   1055       AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRS), DestReg)
   1056                    .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
   1057     } else
   1058       llvm_unreachable("Unknown reg class!");
   1059     break;
   1060   case 8:
   1061     if (ARM::DPRRegClass.hasSubClassEq(RC)) {
   1062       AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRD), DestReg)
   1063                    .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
   1064     } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) {
   1065       MachineInstrBuilder MIB;
   1066 
   1067       if (Subtarget.hasV5TEOps()) {
   1068         MIB = BuildMI(MBB, I, DL, get(ARM::LDRD));
   1069         AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI);
   1070         AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI);
   1071         MIB.addFrameIndex(FI).addReg(0).addImm(0).addMemOperand(MMO);
   1072 
   1073         AddDefaultPred(MIB);
   1074       } else {
   1075         // Fallback to LDM instruction, which has existed since the dawn of
   1076         // time.
   1077         MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::LDMIA))
   1078                                  .addFrameIndex(FI).addMemOperand(MMO));
   1079         MIB = AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI);
   1080         MIB = AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI);
   1081       }
   1082 
   1083       if (TargetRegisterInfo::isPhysicalRegister(DestReg))
   1084         MIB.addReg(DestReg, RegState::ImplicitDefine);
   1085     } else
   1086       llvm_unreachable("Unknown reg class!");
   1087     break;
   1088   case 16:
   1089     if (ARM::DPairRegClass.hasSubClassEq(RC)) {
   1090       if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
   1091         AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1q64), DestReg)
   1092                      .addFrameIndex(FI).addImm(16)
   1093                      .addMemOperand(MMO));
   1094       } else {
   1095         AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMQIA), DestReg)
   1096                        .addFrameIndex(FI)
   1097                        .addMemOperand(MMO));
   1098       }
   1099     } else
   1100       llvm_unreachable("Unknown reg class!");
   1101     break;
   1102   case 24:
   1103     if (ARM::DTripleRegClass.hasSubClassEq(RC)) {
   1104       if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
   1105         AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64TPseudo), DestReg)
   1106                      .addFrameIndex(FI).addImm(16)
   1107                      .addMemOperand(MMO));
   1108       } else {
   1109         MachineInstrBuilder MIB =
   1110           AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA))
   1111                          .addFrameIndex(FI)
   1112                          .addMemOperand(MMO));
   1113         MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI);
   1114         MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI);
   1115         MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI);
   1116         if (TargetRegisterInfo::isPhysicalRegister(DestReg))
   1117           MIB.addReg(DestReg, RegState::ImplicitDefine);
   1118       }
   1119     } else
   1120       llvm_unreachable("Unknown reg class!");
   1121     break;
   1122    case 32:
   1123     if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) {
   1124       if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
   1125         AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64QPseudo), DestReg)
   1126                      .addFrameIndex(FI).addImm(16)
   1127                      .addMemOperand(MMO));
   1128       } else {
   1129         MachineInstrBuilder MIB =
   1130         AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA))
   1131                        .addFrameIndex(FI))
   1132                        .addMemOperand(MMO);
   1133         MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI);
   1134         MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI);
   1135         MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI);
   1136         MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI);
   1137         if (TargetRegisterInfo::isPhysicalRegister(DestReg))
   1138           MIB.addReg(DestReg, RegState::ImplicitDefine);
   1139       }
   1140     } else
   1141       llvm_unreachable("Unknown reg class!");
   1142     break;
   1143   case 64:
   1144     if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) {
   1145       MachineInstrBuilder MIB =
   1146       AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA))
   1147                      .addFrameIndex(FI))
   1148                      .addMemOperand(MMO);
   1149       MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI);
   1150       MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI);
   1151       MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI);
   1152       MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI);
   1153       MIB = AddDReg(MIB, DestReg, ARM::dsub_4, RegState::DefineNoRead, TRI);
   1154       MIB = AddDReg(MIB, DestReg, ARM::dsub_5, RegState::DefineNoRead, TRI);
   1155       MIB = AddDReg(MIB, DestReg, ARM::dsub_6, RegState::DefineNoRead, TRI);
   1156       MIB = AddDReg(MIB, DestReg, ARM::dsub_7, RegState::DefineNoRead, TRI);
   1157       if (TargetRegisterInfo::isPhysicalRegister(DestReg))
   1158         MIB.addReg(DestReg, RegState::ImplicitDefine);
   1159     } else
   1160       llvm_unreachable("Unknown reg class!");
   1161     break;
   1162   default:
   1163     llvm_unreachable("Unknown regclass!");
   1164   }
   1165 }
   1166 
   1167 unsigned
   1168 ARMBaseInstrInfo::isLoadFromStackSlot(const MachineInstr *MI,
   1169                                       int &FrameIndex) const {
   1170   switch (MI->getOpcode()) {
   1171   default: break;
   1172   case ARM::LDRrs:
   1173   case ARM::t2LDRs:  // FIXME: don't use t2LDRs to access frame.
   1174     if (MI->getOperand(1).isFI() &&
   1175         MI->getOperand(2).isReg() &&
   1176         MI->getOperand(3).isImm() &&
   1177         MI->getOperand(2).getReg() == 0 &&
   1178         MI->getOperand(3).getImm() == 0) {
   1179       FrameIndex = MI->getOperand(1).getIndex();
   1180       return MI->getOperand(0).getReg();
   1181     }
   1182     break;
   1183   case ARM::LDRi12:
   1184   case ARM::t2LDRi12:
   1185   case ARM::tLDRspi:
   1186   case ARM::VLDRD:
   1187   case ARM::VLDRS:
   1188     if (MI->getOperand(1).isFI() &&
   1189         MI->getOperand(2).isImm() &&
   1190         MI->getOperand(2).getImm() == 0) {
   1191       FrameIndex = MI->getOperand(1).getIndex();
   1192       return MI->getOperand(0).getReg();
   1193     }
   1194     break;
   1195   case ARM::VLD1q64:
   1196   case ARM::VLD1d64TPseudo:
   1197   case ARM::VLD1d64QPseudo:
   1198     if (MI->getOperand(1).isFI() &&
   1199         MI->getOperand(0).getSubReg() == 0) {
   1200       FrameIndex = MI->getOperand(1).getIndex();
   1201       return MI->getOperand(0).getReg();
   1202     }
   1203     break;
   1204   case ARM::VLDMQIA:
   1205     if (MI->getOperand(1).isFI() &&
   1206         MI->getOperand(0).getSubReg() == 0) {
   1207       FrameIndex = MI->getOperand(1).getIndex();
   1208       return MI->getOperand(0).getReg();
   1209     }
   1210     break;
   1211   }
   1212 
   1213   return 0;
   1214 }
   1215 
   1216 unsigned ARMBaseInstrInfo::isLoadFromStackSlotPostFE(const MachineInstr *MI,
   1217                                              int &FrameIndex) const {
   1218   const MachineMemOperand *Dummy;
   1219   return MI->mayLoad() && hasLoadFromStackSlot(MI, Dummy, FrameIndex);
   1220 }
   1221 
   1222 /// \brief Expands MEMCPY to either LDMIA/STMIA or LDMIA_UPD/STMID_UPD
   1223 /// depending on whether the result is used.
   1224 void ARMBaseInstrInfo::expandMEMCPY(MachineBasicBlock::iterator MBBI) const {
   1225   bool isThumb1 = Subtarget.isThumb1Only();
   1226   bool isThumb2 = Subtarget.isThumb2();
   1227   const ARMBaseInstrInfo *TII = Subtarget.getInstrInfo();
   1228 
   1229   MachineInstr *MI = MBBI;
   1230   DebugLoc dl = MI->getDebugLoc();
   1231   MachineBasicBlock *BB = MI->getParent();
   1232 
   1233   MachineInstrBuilder LDM, STM;
   1234   if (isThumb1 || !MI->getOperand(1).isDead()) {
   1235     LDM = BuildMI(*BB, MI, dl, TII->get(isThumb2 ? ARM::t2LDMIA_UPD
   1236                                                  : isThumb1 ? ARM::tLDMIA_UPD
   1237                                                             : ARM::LDMIA_UPD))
   1238              .addOperand(MI->getOperand(1));
   1239   } else {
   1240     LDM = BuildMI(*BB, MI, dl, TII->get(isThumb2 ? ARM::t2LDMIA : ARM::LDMIA));
   1241   }
   1242 
   1243   if (isThumb1 || !MI->getOperand(0).isDead()) {
   1244     STM = BuildMI(*BB, MI, dl, TII->get(isThumb2 ? ARM::t2STMIA_UPD
   1245                                                  : isThumb1 ? ARM::tSTMIA_UPD
   1246                                                             : ARM::STMIA_UPD))
   1247              .addOperand(MI->getOperand(0));
   1248   } else {
   1249     STM = BuildMI(*BB, MI, dl, TII->get(isThumb2 ? ARM::t2STMIA : ARM::STMIA));
   1250   }
   1251 
   1252   AddDefaultPred(LDM.addOperand(MI->getOperand(3)));
   1253   AddDefaultPred(STM.addOperand(MI->getOperand(2)));
   1254 
   1255   // Sort the scratch registers into ascending order.
   1256   const TargetRegisterInfo &TRI = getRegisterInfo();
   1257   llvm::SmallVector<unsigned, 6> ScratchRegs;
   1258   for(unsigned I = 5; I < MI->getNumOperands(); ++I)
   1259     ScratchRegs.push_back(MI->getOperand(I).getReg());
   1260   std::sort(ScratchRegs.begin(), ScratchRegs.end(),
   1261             [&TRI](const unsigned &Reg1,
   1262                    const unsigned &Reg2) -> bool {
   1263               return TRI.getEncodingValue(Reg1) <
   1264                      TRI.getEncodingValue(Reg2);
   1265             });
   1266 
   1267   for (const auto &Reg : ScratchRegs) {
   1268     LDM.addReg(Reg, RegState::Define);
   1269     STM.addReg(Reg, RegState::Kill);
   1270   }
   1271 
   1272   BB->erase(MBBI);
   1273 }
   1274 
   1275 
   1276 bool
   1277 ARMBaseInstrInfo::expandPostRAPseudo(MachineBasicBlock::iterator MI) const {
   1278   MachineFunction &MF = *MI->getParent()->getParent();
   1279   Reloc::Model RM = MF.getTarget().getRelocationModel();
   1280 
   1281   if (MI->getOpcode() == TargetOpcode::LOAD_STACK_GUARD) {
   1282     assert(getSubtarget().getTargetTriple().isOSBinFormatMachO() &&
   1283            "LOAD_STACK_GUARD currently supported only for MachO.");
   1284     expandLoadStackGuard(MI, RM);
   1285     MI->getParent()->erase(MI);
   1286     return true;
   1287   }
   1288 
   1289   if (MI->getOpcode() == ARM::MEMCPY) {
   1290     expandMEMCPY(MI);
   1291     return true;
   1292   }
   1293 
   1294   // This hook gets to expand COPY instructions before they become
   1295   // copyPhysReg() calls.  Look for VMOVS instructions that can legally be
   1296   // widened to VMOVD.  We prefer the VMOVD when possible because it may be
   1297   // changed into a VORR that can go down the NEON pipeline.
   1298   if (!WidenVMOVS || !MI->isCopy() || Subtarget.isCortexA15() ||
   1299       Subtarget.isFPOnlySP())
   1300     return false;
   1301 
   1302   // Look for a copy between even S-registers.  That is where we keep floats
   1303   // when using NEON v2f32 instructions for f32 arithmetic.
   1304   unsigned DstRegS = MI->getOperand(0).getReg();
   1305   unsigned SrcRegS = MI->getOperand(1).getReg();
   1306   if (!ARM::SPRRegClass.contains(DstRegS, SrcRegS))
   1307     return false;
   1308 
   1309   const TargetRegisterInfo *TRI = &getRegisterInfo();
   1310   unsigned DstRegD = TRI->getMatchingSuperReg(DstRegS, ARM::ssub_0,
   1311                                               &ARM::DPRRegClass);
   1312   unsigned SrcRegD = TRI->getMatchingSuperReg(SrcRegS, ARM::ssub_0,
   1313                                               &ARM::DPRRegClass);
   1314   if (!DstRegD || !SrcRegD)
   1315     return false;
   1316 
   1317   // We want to widen this into a DstRegD = VMOVD SrcRegD copy.  This is only
   1318   // legal if the COPY already defines the full DstRegD, and it isn't a
   1319   // sub-register insertion.
   1320   if (!MI->definesRegister(DstRegD, TRI) || MI->readsRegister(DstRegD, TRI))
   1321     return false;
   1322 
   1323   // A dead copy shouldn't show up here, but reject it just in case.
   1324   if (MI->getOperand(0).isDead())
   1325     return false;
   1326 
   1327   // All clear, widen the COPY.
   1328   DEBUG(dbgs() << "widening:    " << *MI);
   1329   MachineInstrBuilder MIB(*MI->getParent()->getParent(), MI);
   1330 
   1331   // Get rid of the old <imp-def> of DstRegD.  Leave it if it defines a Q-reg
   1332   // or some other super-register.
   1333   int ImpDefIdx = MI->findRegisterDefOperandIdx(DstRegD);
   1334   if (ImpDefIdx != -1)
   1335     MI->RemoveOperand(ImpDefIdx);
   1336 
   1337   // Change the opcode and operands.
   1338   MI->setDesc(get(ARM::VMOVD));
   1339   MI->getOperand(0).setReg(DstRegD);
   1340   MI->getOperand(1).setReg(SrcRegD);
   1341   AddDefaultPred(MIB);
   1342 
   1343   // We are now reading SrcRegD instead of SrcRegS.  This may upset the
   1344   // register scavenger and machine verifier, so we need to indicate that we
   1345   // are reading an undefined value from SrcRegD, but a proper value from
   1346   // SrcRegS.
   1347   MI->getOperand(1).setIsUndef();
   1348   MIB.addReg(SrcRegS, RegState::Implicit);
   1349 
   1350   // SrcRegD may actually contain an unrelated value in the ssub_1
   1351   // sub-register.  Don't kill it.  Only kill the ssub_0 sub-register.
   1352   if (MI->getOperand(1).isKill()) {
   1353     MI->getOperand(1).setIsKill(false);
   1354     MI->addRegisterKilled(SrcRegS, TRI, true);
   1355   }
   1356 
   1357   DEBUG(dbgs() << "replaced by: " << *MI);
   1358   return true;
   1359 }
   1360 
   1361 /// Create a copy of a const pool value. Update CPI to the new index and return
   1362 /// the label UID.
   1363 static unsigned duplicateCPV(MachineFunction &MF, unsigned &CPI) {
   1364   MachineConstantPool *MCP = MF.getConstantPool();
   1365   ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
   1366 
   1367   const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPI];
   1368   assert(MCPE.isMachineConstantPoolEntry() &&
   1369          "Expecting a machine constantpool entry!");
   1370   ARMConstantPoolValue *ACPV =
   1371     static_cast<ARMConstantPoolValue*>(MCPE.Val.MachineCPVal);
   1372 
   1373   unsigned PCLabelId = AFI->createPICLabelUId();
   1374   ARMConstantPoolValue *NewCPV = nullptr;
   1375 
   1376   // FIXME: The below assumes PIC relocation model and that the function
   1377   // is Thumb mode (t1 or t2). PCAdjustment would be 8 for ARM mode PIC, and
   1378   // zero for non-PIC in ARM or Thumb. The callers are all of thumb LDR
   1379   // instructions, so that's probably OK, but is PIC always correct when
   1380   // we get here?
   1381   if (ACPV->isGlobalValue())
   1382     NewCPV = ARMConstantPoolConstant::Create(
   1383         cast<ARMConstantPoolConstant>(ACPV)->getGV(), PCLabelId, ARMCP::CPValue,
   1384         4, ACPV->getModifier(), ACPV->mustAddCurrentAddress());
   1385   else if (ACPV->isExtSymbol())
   1386     NewCPV = ARMConstantPoolSymbol::
   1387       Create(MF.getFunction()->getContext(),
   1388              cast<ARMConstantPoolSymbol>(ACPV)->getSymbol(), PCLabelId, 4);
   1389   else if (ACPV->isBlockAddress())
   1390     NewCPV = ARMConstantPoolConstant::
   1391       Create(cast<ARMConstantPoolConstant>(ACPV)->getBlockAddress(), PCLabelId,
   1392              ARMCP::CPBlockAddress, 4);
   1393   else if (ACPV->isLSDA())
   1394     NewCPV = ARMConstantPoolConstant::Create(MF.getFunction(), PCLabelId,
   1395                                              ARMCP::CPLSDA, 4);
   1396   else if (ACPV->isMachineBasicBlock())
   1397     NewCPV = ARMConstantPoolMBB::
   1398       Create(MF.getFunction()->getContext(),
   1399              cast<ARMConstantPoolMBB>(ACPV)->getMBB(), PCLabelId, 4);
   1400   else
   1401     llvm_unreachable("Unexpected ARM constantpool value type!!");
   1402   CPI = MCP->getConstantPoolIndex(NewCPV, MCPE.getAlignment());
   1403   return PCLabelId;
   1404 }
   1405 
   1406 void ARMBaseInstrInfo::
   1407 reMaterialize(MachineBasicBlock &MBB,
   1408               MachineBasicBlock::iterator I,
   1409               unsigned DestReg, unsigned SubIdx,
   1410               const MachineInstr *Orig,
   1411               const TargetRegisterInfo &TRI) const {
   1412   unsigned Opcode = Orig->getOpcode();
   1413   switch (Opcode) {
   1414   default: {
   1415     MachineInstr *MI = MBB.getParent()->CloneMachineInstr(Orig);
   1416     MI->substituteRegister(Orig->getOperand(0).getReg(), DestReg, SubIdx, TRI);
   1417     MBB.insert(I, MI);
   1418     break;
   1419   }
   1420   case ARM::tLDRpci_pic:
   1421   case ARM::t2LDRpci_pic: {
   1422     MachineFunction &MF = *MBB.getParent();
   1423     unsigned CPI = Orig->getOperand(1).getIndex();
   1424     unsigned PCLabelId = duplicateCPV(MF, CPI);
   1425     MachineInstrBuilder MIB = BuildMI(MBB, I, Orig->getDebugLoc(), get(Opcode),
   1426                                       DestReg)
   1427       .addConstantPoolIndex(CPI).addImm(PCLabelId);
   1428     MIB->setMemRefs(Orig->memoperands_begin(), Orig->memoperands_end());
   1429     break;
   1430   }
   1431   }
   1432 }
   1433 
   1434 MachineInstr *
   1435 ARMBaseInstrInfo::duplicate(MachineInstr *Orig, MachineFunction &MF) const {
   1436   MachineInstr *MI = TargetInstrInfo::duplicate(Orig, MF);
   1437   switch(Orig->getOpcode()) {
   1438   case ARM::tLDRpci_pic:
   1439   case ARM::t2LDRpci_pic: {
   1440     unsigned CPI = Orig->getOperand(1).getIndex();
   1441     unsigned PCLabelId = duplicateCPV(MF, CPI);
   1442     Orig->getOperand(1).setIndex(CPI);
   1443     Orig->getOperand(2).setImm(PCLabelId);
   1444     break;
   1445   }
   1446   }
   1447   return MI;
   1448 }
   1449 
   1450 bool ARMBaseInstrInfo::produceSameValue(const MachineInstr *MI0,
   1451                                         const MachineInstr *MI1,
   1452                                         const MachineRegisterInfo *MRI) const {
   1453   unsigned Opcode = MI0->getOpcode();
   1454   if (Opcode == ARM::t2LDRpci ||
   1455       Opcode == ARM::t2LDRpci_pic ||
   1456       Opcode == ARM::tLDRpci ||
   1457       Opcode == ARM::tLDRpci_pic ||
   1458       Opcode == ARM::LDRLIT_ga_pcrel ||
   1459       Opcode == ARM::LDRLIT_ga_pcrel_ldr ||
   1460       Opcode == ARM::tLDRLIT_ga_pcrel ||
   1461       Opcode == ARM::MOV_ga_pcrel ||
   1462       Opcode == ARM::MOV_ga_pcrel_ldr ||
   1463       Opcode == ARM::t2MOV_ga_pcrel) {
   1464     if (MI1->getOpcode() != Opcode)
   1465       return false;
   1466     if (MI0->getNumOperands() != MI1->getNumOperands())
   1467       return false;
   1468 
   1469     const MachineOperand &MO0 = MI0->getOperand(1);
   1470     const MachineOperand &MO1 = MI1->getOperand(1);
   1471     if (MO0.getOffset() != MO1.getOffset())
   1472       return false;
   1473 
   1474     if (Opcode == ARM::LDRLIT_ga_pcrel ||
   1475         Opcode == ARM::LDRLIT_ga_pcrel_ldr ||
   1476         Opcode == ARM::tLDRLIT_ga_pcrel ||
   1477         Opcode == ARM::MOV_ga_pcrel ||
   1478         Opcode == ARM::MOV_ga_pcrel_ldr ||
   1479         Opcode == ARM::t2MOV_ga_pcrel)
   1480       // Ignore the PC labels.
   1481       return MO0.getGlobal() == MO1.getGlobal();
   1482 
   1483     const MachineFunction *MF = MI0->getParent()->getParent();
   1484     const MachineConstantPool *MCP = MF->getConstantPool();
   1485     int CPI0 = MO0.getIndex();
   1486     int CPI1 = MO1.getIndex();
   1487     const MachineConstantPoolEntry &MCPE0 = MCP->getConstants()[CPI0];
   1488     const MachineConstantPoolEntry &MCPE1 = MCP->getConstants()[CPI1];
   1489     bool isARMCP0 = MCPE0.isMachineConstantPoolEntry();
   1490     bool isARMCP1 = MCPE1.isMachineConstantPoolEntry();
   1491     if (isARMCP0 && isARMCP1) {
   1492       ARMConstantPoolValue *ACPV0 =
   1493         static_cast<ARMConstantPoolValue*>(MCPE0.Val.MachineCPVal);
   1494       ARMConstantPoolValue *ACPV1 =
   1495         static_cast<ARMConstantPoolValue*>(MCPE1.Val.MachineCPVal);
   1496       return ACPV0->hasSameValue(ACPV1);
   1497     } else if (!isARMCP0 && !isARMCP1) {
   1498       return MCPE0.Val.ConstVal == MCPE1.Val.ConstVal;
   1499     }
   1500     return false;
   1501   } else if (Opcode == ARM::PICLDR) {
   1502     if (MI1->getOpcode() != Opcode)
   1503       return false;
   1504     if (MI0->getNumOperands() != MI1->getNumOperands())
   1505       return false;
   1506 
   1507     unsigned Addr0 = MI0->getOperand(1).getReg();
   1508     unsigned Addr1 = MI1->getOperand(1).getReg();
   1509     if (Addr0 != Addr1) {
   1510       if (!MRI ||
   1511           !TargetRegisterInfo::isVirtualRegister(Addr0) ||
   1512           !TargetRegisterInfo::isVirtualRegister(Addr1))
   1513         return false;
   1514 
   1515       // This assumes SSA form.
   1516       MachineInstr *Def0 = MRI->getVRegDef(Addr0);
   1517       MachineInstr *Def1 = MRI->getVRegDef(Addr1);
   1518       // Check if the loaded value, e.g. a constantpool of a global address, are
   1519       // the same.
   1520       if (!produceSameValue(Def0, Def1, MRI))
   1521         return false;
   1522     }
   1523 
   1524     for (unsigned i = 3, e = MI0->getNumOperands(); i != e; ++i) {
   1525       // %vreg12<def> = PICLDR %vreg11, 0, pred:14, pred:%noreg
   1526       const MachineOperand &MO0 = MI0->getOperand(i);
   1527       const MachineOperand &MO1 = MI1->getOperand(i);
   1528       if (!MO0.isIdenticalTo(MO1))
   1529         return false;
   1530     }
   1531     return true;
   1532   }
   1533 
   1534   return MI0->isIdenticalTo(MI1, MachineInstr::IgnoreVRegDefs);
   1535 }
   1536 
   1537 /// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler to
   1538 /// determine if two loads are loading from the same base address. It should
   1539 /// only return true if the base pointers are the same and the only differences
   1540 /// between the two addresses is the offset. It also returns the offsets by
   1541 /// reference.
   1542 ///
   1543 /// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched
   1544 /// is permanently disabled.
   1545 bool ARMBaseInstrInfo::areLoadsFromSameBasePtr(SDNode *Load1, SDNode *Load2,
   1546                                                int64_t &Offset1,
   1547                                                int64_t &Offset2) const {
   1548   // Don't worry about Thumb: just ARM and Thumb2.
   1549   if (Subtarget.isThumb1Only()) return false;
   1550 
   1551   if (!Load1->isMachineOpcode() || !Load2->isMachineOpcode())
   1552     return false;
   1553 
   1554   switch (Load1->getMachineOpcode()) {
   1555   default:
   1556     return false;
   1557   case ARM::LDRi12:
   1558   case ARM::LDRBi12:
   1559   case ARM::LDRD:
   1560   case ARM::LDRH:
   1561   case ARM::LDRSB:
   1562   case ARM::LDRSH:
   1563   case ARM::VLDRD:
   1564   case ARM::VLDRS:
   1565   case ARM::t2LDRi8:
   1566   case ARM::t2LDRBi8:
   1567   case ARM::t2LDRDi8:
   1568   case ARM::t2LDRSHi8:
   1569   case ARM::t2LDRi12:
   1570   case ARM::t2LDRBi12:
   1571   case ARM::t2LDRSHi12:
   1572     break;
   1573   }
   1574 
   1575   switch (Load2->getMachineOpcode()) {
   1576   default:
   1577     return false;
   1578   case ARM::LDRi12:
   1579   case ARM::LDRBi12:
   1580   case ARM::LDRD:
   1581   case ARM::LDRH:
   1582   case ARM::LDRSB:
   1583   case ARM::LDRSH:
   1584   case ARM::VLDRD:
   1585   case ARM::VLDRS:
   1586   case ARM::t2LDRi8:
   1587   case ARM::t2LDRBi8:
   1588   case ARM::t2LDRSHi8:
   1589   case ARM::t2LDRi12:
   1590   case ARM::t2LDRBi12:
   1591   case ARM::t2LDRSHi12:
   1592     break;
   1593   }
   1594 
   1595   // Check if base addresses and chain operands match.
   1596   if (Load1->getOperand(0) != Load2->getOperand(0) ||
   1597       Load1->getOperand(4) != Load2->getOperand(4))
   1598     return false;
   1599 
   1600   // Index should be Reg0.
   1601   if (Load1->getOperand(3) != Load2->getOperand(3))
   1602     return false;
   1603 
   1604   // Determine the offsets.
   1605   if (isa<ConstantSDNode>(Load1->getOperand(1)) &&
   1606       isa<ConstantSDNode>(Load2->getOperand(1))) {
   1607     Offset1 = cast<ConstantSDNode>(Load1->getOperand(1))->getSExtValue();
   1608     Offset2 = cast<ConstantSDNode>(Load2->getOperand(1))->getSExtValue();
   1609     return true;
   1610   }
   1611 
   1612   return false;
   1613 }
   1614 
   1615 /// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to
   1616 /// determine (in conjunction with areLoadsFromSameBasePtr) if two loads should
   1617 /// be scheduled togther. On some targets if two loads are loading from
   1618 /// addresses in the same cache line, it's better if they are scheduled
   1619 /// together. This function takes two integers that represent the load offsets
   1620 /// from the common base address. It returns true if it decides it's desirable
   1621 /// to schedule the two loads together. "NumLoads" is the number of loads that
   1622 /// have already been scheduled after Load1.
   1623 ///
   1624 /// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched
   1625 /// is permanently disabled.
   1626 bool ARMBaseInstrInfo::shouldScheduleLoadsNear(SDNode *Load1, SDNode *Load2,
   1627                                                int64_t Offset1, int64_t Offset2,
   1628                                                unsigned NumLoads) const {
   1629   // Don't worry about Thumb: just ARM and Thumb2.
   1630   if (Subtarget.isThumb1Only()) return false;
   1631 
   1632   assert(Offset2 > Offset1);
   1633 
   1634   if ((Offset2 - Offset1) / 8 > 64)
   1635     return false;
   1636 
   1637   // Check if the machine opcodes are different. If they are different
   1638   // then we consider them to not be of the same base address,
   1639   // EXCEPT in the case of Thumb2 byte loads where one is LDRBi8 and the other LDRBi12.
   1640   // In this case, they are considered to be the same because they are different
   1641   // encoding forms of the same basic instruction.
   1642   if ((Load1->getMachineOpcode() != Load2->getMachineOpcode()) &&
   1643       !((Load1->getMachineOpcode() == ARM::t2LDRBi8 &&
   1644          Load2->getMachineOpcode() == ARM::t2LDRBi12) ||
   1645         (Load1->getMachineOpcode() == ARM::t2LDRBi12 &&
   1646          Load2->getMachineOpcode() == ARM::t2LDRBi8)))
   1647     return false;  // FIXME: overly conservative?
   1648 
   1649   // Four loads in a row should be sufficient.
   1650   if (NumLoads >= 3)
   1651     return false;
   1652 
   1653   return true;
   1654 }
   1655 
   1656 bool ARMBaseInstrInfo::isSchedulingBoundary(const MachineInstr *MI,
   1657                                             const MachineBasicBlock *MBB,
   1658                                             const MachineFunction &MF) const {
   1659   // Debug info is never a scheduling boundary. It's necessary to be explicit
   1660   // due to the special treatment of IT instructions below, otherwise a
   1661   // dbg_value followed by an IT will result in the IT instruction being
   1662   // considered a scheduling hazard, which is wrong. It should be the actual
   1663   // instruction preceding the dbg_value instruction(s), just like it is
   1664   // when debug info is not present.
   1665   if (MI->isDebugValue())
   1666     return false;
   1667 
   1668   // Terminators and labels can't be scheduled around.
   1669   if (MI->isTerminator() || MI->isPosition())
   1670     return true;
   1671 
   1672   // Treat the start of the IT block as a scheduling boundary, but schedule
   1673   // t2IT along with all instructions following it.
   1674   // FIXME: This is a big hammer. But the alternative is to add all potential
   1675   // true and anti dependencies to IT block instructions as implicit operands
   1676   // to the t2IT instruction. The added compile time and complexity does not
   1677   // seem worth it.
   1678   MachineBasicBlock::const_iterator I = MI;
   1679   // Make sure to skip any dbg_value instructions
   1680   while (++I != MBB->end() && I->isDebugValue())
   1681     ;
   1682   if (I != MBB->end() && I->getOpcode() == ARM::t2IT)
   1683     return true;
   1684 
   1685   // Don't attempt to schedule around any instruction that defines
   1686   // a stack-oriented pointer, as it's unlikely to be profitable. This
   1687   // saves compile time, because it doesn't require every single
   1688   // stack slot reference to depend on the instruction that does the
   1689   // modification.
   1690   // Calls don't actually change the stack pointer, even if they have imp-defs.
   1691   // No ARM calling conventions change the stack pointer. (X86 calling
   1692   // conventions sometimes do).
   1693   if (!MI->isCall() && MI->definesRegister(ARM::SP))
   1694     return true;
   1695 
   1696   return false;
   1697 }
   1698 
   1699 bool ARMBaseInstrInfo::
   1700 isProfitableToIfCvt(MachineBasicBlock &MBB,
   1701                     unsigned NumCycles, unsigned ExtraPredCycles,
   1702                     BranchProbability Probability) const {
   1703   if (!NumCycles)
   1704     return false;
   1705 
   1706   // If we are optimizing for size, see if the branch in the predecessor can be
   1707   // lowered to cbn?z by the constant island lowering pass, and return false if
   1708   // so. This results in a shorter instruction sequence.
   1709   if (MBB.getParent()->getFunction()->optForSize()) {
   1710     MachineBasicBlock *Pred = *MBB.pred_begin();
   1711     if (!Pred->empty()) {
   1712       MachineInstr *LastMI = &*Pred->rbegin();
   1713       if (LastMI->getOpcode() == ARM::t2Bcc) {
   1714         MachineBasicBlock::iterator CmpMI = LastMI;
   1715         if (CmpMI != Pred->begin()) {
   1716           --CmpMI;
   1717           if (CmpMI->getOpcode() == ARM::tCMPi8 ||
   1718               CmpMI->getOpcode() == ARM::t2CMPri) {
   1719             unsigned Reg = CmpMI->getOperand(0).getReg();
   1720             unsigned PredReg = 0;
   1721             ARMCC::CondCodes P = getInstrPredicate(CmpMI, PredReg);
   1722             if (P == ARMCC::AL && CmpMI->getOperand(1).getImm() == 0 &&
   1723                 isARMLowRegister(Reg))
   1724               return false;
   1725           }
   1726         }
   1727       }
   1728     }
   1729   }
   1730 
   1731   // Attempt to estimate the relative costs of predication versus branching.
   1732   // Here we scale up each component of UnpredCost to avoid precision issue when
   1733   // scaling NumCycles by Probability.
   1734   const unsigned ScalingUpFactor = 1024;
   1735   unsigned UnpredCost = Probability.scale(NumCycles * ScalingUpFactor);
   1736   UnpredCost += ScalingUpFactor; // The branch itself
   1737   UnpredCost += Subtarget.getMispredictionPenalty() * ScalingUpFactor / 10;
   1738 
   1739   return (NumCycles + ExtraPredCycles) * ScalingUpFactor <= UnpredCost;
   1740 }
   1741 
   1742 bool ARMBaseInstrInfo::
   1743 isProfitableToIfCvt(MachineBasicBlock &TMBB,
   1744                     unsigned TCycles, unsigned TExtra,
   1745                     MachineBasicBlock &FMBB,
   1746                     unsigned FCycles, unsigned FExtra,
   1747                     BranchProbability Probability) const {
   1748   if (!TCycles || !FCycles)
   1749     return false;
   1750 
   1751   // Attempt to estimate the relative costs of predication versus branching.
   1752   // Here we scale up each component of UnpredCost to avoid precision issue when
   1753   // scaling TCycles/FCycles by Probability.
   1754   const unsigned ScalingUpFactor = 1024;
   1755   unsigned TUnpredCost = Probability.scale(TCycles * ScalingUpFactor);
   1756   unsigned FUnpredCost =
   1757       Probability.getCompl().scale(FCycles * ScalingUpFactor);
   1758   unsigned UnpredCost = TUnpredCost + FUnpredCost;
   1759   UnpredCost += 1 * ScalingUpFactor; // The branch itself
   1760   UnpredCost += Subtarget.getMispredictionPenalty() * ScalingUpFactor / 10;
   1761 
   1762   return (TCycles + FCycles + TExtra + FExtra) * ScalingUpFactor <= UnpredCost;
   1763 }
   1764 
   1765 bool
   1766 ARMBaseInstrInfo::isProfitableToUnpredicate(MachineBasicBlock &TMBB,
   1767                                             MachineBasicBlock &FMBB) const {
   1768   // Reduce false anti-dependencies to let Swift's out-of-order execution
   1769   // engine do its thing.
   1770   return Subtarget.isSwift();
   1771 }
   1772 
   1773 /// getInstrPredicate - If instruction is predicated, returns its predicate
   1774 /// condition, otherwise returns AL. It also returns the condition code
   1775 /// register by reference.
   1776 ARMCC::CondCodes
   1777 llvm::getInstrPredicate(const MachineInstr *MI, unsigned &PredReg) {
   1778   int PIdx = MI->findFirstPredOperandIdx();
   1779   if (PIdx == -1) {
   1780     PredReg = 0;
   1781     return ARMCC::AL;
   1782   }
   1783 
   1784   PredReg = MI->getOperand(PIdx+1).getReg();
   1785   return (ARMCC::CondCodes)MI->getOperand(PIdx).getImm();
   1786 }
   1787 
   1788 
   1789 unsigned llvm::getMatchingCondBranchOpcode(unsigned Opc) {
   1790   if (Opc == ARM::B)
   1791     return ARM::Bcc;
   1792   if (Opc == ARM::tB)
   1793     return ARM::tBcc;
   1794   if (Opc == ARM::t2B)
   1795     return ARM::t2Bcc;
   1796 
   1797   llvm_unreachable("Unknown unconditional branch opcode!");
   1798 }
   1799 
   1800 MachineInstr *ARMBaseInstrInfo::commuteInstructionImpl(MachineInstr *MI,
   1801                                                        bool NewMI,
   1802                                                        unsigned OpIdx1,
   1803                                                        unsigned OpIdx2) const {
   1804   switch (MI->getOpcode()) {
   1805   case ARM::MOVCCr:
   1806   case ARM::t2MOVCCr: {
   1807     // MOVCC can be commuted by inverting the condition.
   1808     unsigned PredReg = 0;
   1809     ARMCC::CondCodes CC = getInstrPredicate(MI, PredReg);
   1810     // MOVCC AL can't be inverted. Shouldn't happen.
   1811     if (CC == ARMCC::AL || PredReg != ARM::CPSR)
   1812       return nullptr;
   1813     MI = TargetInstrInfo::commuteInstructionImpl(MI, NewMI, OpIdx1, OpIdx2);
   1814     if (!MI)
   1815       return nullptr;
   1816     // After swapping the MOVCC operands, also invert the condition.
   1817     MI->getOperand(MI->findFirstPredOperandIdx())
   1818       .setImm(ARMCC::getOppositeCondition(CC));
   1819     return MI;
   1820   }
   1821   }
   1822   return TargetInstrInfo::commuteInstructionImpl(MI, NewMI, OpIdx1, OpIdx2);
   1823 }
   1824 
   1825 /// Identify instructions that can be folded into a MOVCC instruction, and
   1826 /// return the defining instruction.
   1827 static MachineInstr *canFoldIntoMOVCC(unsigned Reg,
   1828                                       const MachineRegisterInfo &MRI,
   1829                                       const TargetInstrInfo *TII) {
   1830   if (!TargetRegisterInfo::isVirtualRegister(Reg))
   1831     return nullptr;
   1832   if (!MRI.hasOneNonDBGUse(Reg))
   1833     return nullptr;
   1834   MachineInstr *MI = MRI.getVRegDef(Reg);
   1835   if (!MI)
   1836     return nullptr;
   1837   // MI is folded into the MOVCC by predicating it.
   1838   if (!MI->isPredicable())
   1839     return nullptr;
   1840   // Check if MI has any non-dead defs or physreg uses. This also detects
   1841   // predicated instructions which will be reading CPSR.
   1842   for (unsigned i = 1, e = MI->getNumOperands(); i != e; ++i) {
   1843     const MachineOperand &MO = MI->getOperand(i);
   1844     // Reject frame index operands, PEI can't handle the predicated pseudos.
   1845     if (MO.isFI() || MO.isCPI() || MO.isJTI())
   1846       return nullptr;
   1847     if (!MO.isReg())
   1848       continue;
   1849     // MI can't have any tied operands, that would conflict with predication.
   1850     if (MO.isTied())
   1851       return nullptr;
   1852     if (TargetRegisterInfo::isPhysicalRegister(MO.getReg()))
   1853       return nullptr;
   1854     if (MO.isDef() && !MO.isDead())
   1855       return nullptr;
   1856   }
   1857   bool DontMoveAcrossStores = true;
   1858   if (!MI->isSafeToMove(/* AliasAnalysis = */ nullptr, DontMoveAcrossStores))
   1859     return nullptr;
   1860   return MI;
   1861 }
   1862 
   1863 bool ARMBaseInstrInfo::analyzeSelect(const MachineInstr *MI,
   1864                                      SmallVectorImpl<MachineOperand> &Cond,
   1865                                      unsigned &TrueOp, unsigned &FalseOp,
   1866                                      bool &Optimizable) const {
   1867   assert((MI->getOpcode() == ARM::MOVCCr || MI->getOpcode() == ARM::t2MOVCCr) &&
   1868          "Unknown select instruction");
   1869   // MOVCC operands:
   1870   // 0: Def.
   1871   // 1: True use.
   1872   // 2: False use.
   1873   // 3: Condition code.
   1874   // 4: CPSR use.
   1875   TrueOp = 1;
   1876   FalseOp = 2;
   1877   Cond.push_back(MI->getOperand(3));
   1878   Cond.push_back(MI->getOperand(4));
   1879   // We can always fold a def.
   1880   Optimizable = true;
   1881   return false;
   1882 }
   1883 
   1884 MachineInstr *
   1885 ARMBaseInstrInfo::optimizeSelect(MachineInstr *MI,
   1886                                  SmallPtrSetImpl<MachineInstr *> &SeenMIs,
   1887                                  bool PreferFalse) const {
   1888   assert((MI->getOpcode() == ARM::MOVCCr || MI->getOpcode() == ARM::t2MOVCCr) &&
   1889          "Unknown select instruction");
   1890   MachineRegisterInfo &MRI = MI->getParent()->getParent()->getRegInfo();
   1891   MachineInstr *DefMI = canFoldIntoMOVCC(MI->getOperand(2).getReg(), MRI, this);
   1892   bool Invert = !DefMI;
   1893   if (!DefMI)
   1894     DefMI = canFoldIntoMOVCC(MI->getOperand(1).getReg(), MRI, this);
   1895   if (!DefMI)
   1896     return nullptr;
   1897 
   1898   // Find new register class to use.
   1899   MachineOperand FalseReg = MI->getOperand(Invert ? 2 : 1);
   1900   unsigned       DestReg  = MI->getOperand(0).getReg();
   1901   const TargetRegisterClass *PreviousClass = MRI.getRegClass(FalseReg.getReg());
   1902   if (!MRI.constrainRegClass(DestReg, PreviousClass))
   1903     return nullptr;
   1904 
   1905   // Create a new predicated version of DefMI.
   1906   // Rfalse is the first use.
   1907   MachineInstrBuilder NewMI = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(),
   1908                                       DefMI->getDesc(), DestReg);
   1909 
   1910   // Copy all the DefMI operands, excluding its (null) predicate.
   1911   const MCInstrDesc &DefDesc = DefMI->getDesc();
   1912   for (unsigned i = 1, e = DefDesc.getNumOperands();
   1913        i != e && !DefDesc.OpInfo[i].isPredicate(); ++i)
   1914     NewMI.addOperand(DefMI->getOperand(i));
   1915 
   1916   unsigned CondCode = MI->getOperand(3).getImm();
   1917   if (Invert)
   1918     NewMI.addImm(ARMCC::getOppositeCondition(ARMCC::CondCodes(CondCode)));
   1919   else
   1920     NewMI.addImm(CondCode);
   1921   NewMI.addOperand(MI->getOperand(4));
   1922 
   1923   // DefMI is not the -S version that sets CPSR, so add an optional %noreg.
   1924   if (NewMI->hasOptionalDef())
   1925     AddDefaultCC(NewMI);
   1926 
   1927   // The output register value when the predicate is false is an implicit
   1928   // register operand tied to the first def.
   1929   // The tie makes the register allocator ensure the FalseReg is allocated the
   1930   // same register as operand 0.
   1931   FalseReg.setImplicit();
   1932   NewMI.addOperand(FalseReg);
   1933   NewMI->tieOperands(0, NewMI->getNumOperands() - 1);
   1934 
   1935   // Update SeenMIs set: register newly created MI and erase removed DefMI.
   1936   SeenMIs.insert(NewMI);
   1937   SeenMIs.erase(DefMI);
   1938 
   1939   // If MI is inside a loop, and DefMI is outside the loop, then kill flags on
   1940   // DefMI would be invalid when tranferred inside the loop.  Checking for a
   1941   // loop is expensive, but at least remove kill flags if they are in different
   1942   // BBs.
   1943   if (DefMI->getParent() != MI->getParent())
   1944     NewMI->clearKillInfo();
   1945 
   1946   // The caller will erase MI, but not DefMI.
   1947   DefMI->eraseFromParent();
   1948   return NewMI;
   1949 }
   1950 
   1951 /// Map pseudo instructions that imply an 'S' bit onto real opcodes. Whether the
   1952 /// instruction is encoded with an 'S' bit is determined by the optional CPSR
   1953 /// def operand.
   1954 ///
   1955 /// This will go away once we can teach tblgen how to set the optional CPSR def
   1956 /// operand itself.
   1957 struct AddSubFlagsOpcodePair {
   1958   uint16_t PseudoOpc;
   1959   uint16_t MachineOpc;
   1960 };
   1961 
   1962 static const AddSubFlagsOpcodePair AddSubFlagsOpcodeMap[] = {
   1963   {ARM::ADDSri, ARM::ADDri},
   1964   {ARM::ADDSrr, ARM::ADDrr},
   1965   {ARM::ADDSrsi, ARM::ADDrsi},
   1966   {ARM::ADDSrsr, ARM::ADDrsr},
   1967 
   1968   {ARM::SUBSri, ARM::SUBri},
   1969   {ARM::SUBSrr, ARM::SUBrr},
   1970   {ARM::SUBSrsi, ARM::SUBrsi},
   1971   {ARM::SUBSrsr, ARM::SUBrsr},
   1972 
   1973   {ARM::RSBSri, ARM::RSBri},
   1974   {ARM::RSBSrsi, ARM::RSBrsi},
   1975   {ARM::RSBSrsr, ARM::RSBrsr},
   1976 
   1977   {ARM::t2ADDSri, ARM::t2ADDri},
   1978   {ARM::t2ADDSrr, ARM::t2ADDrr},
   1979   {ARM::t2ADDSrs, ARM::t2ADDrs},
   1980 
   1981   {ARM::t2SUBSri, ARM::t2SUBri},
   1982   {ARM::t2SUBSrr, ARM::t2SUBrr},
   1983   {ARM::t2SUBSrs, ARM::t2SUBrs},
   1984 
   1985   {ARM::t2RSBSri, ARM::t2RSBri},
   1986   {ARM::t2RSBSrs, ARM::t2RSBrs},
   1987 };
   1988 
   1989 unsigned llvm::convertAddSubFlagsOpcode(unsigned OldOpc) {
   1990   for (unsigned i = 0, e = array_lengthof(AddSubFlagsOpcodeMap); i != e; ++i)
   1991     if (OldOpc == AddSubFlagsOpcodeMap[i].PseudoOpc)
   1992       return AddSubFlagsOpcodeMap[i].MachineOpc;
   1993   return 0;
   1994 }
   1995 
   1996 void llvm::emitARMRegPlusImmediate(MachineBasicBlock &MBB,
   1997                                MachineBasicBlock::iterator &MBBI, DebugLoc dl,
   1998                                unsigned DestReg, unsigned BaseReg, int NumBytes,
   1999                                ARMCC::CondCodes Pred, unsigned PredReg,
   2000                                const ARMBaseInstrInfo &TII, unsigned MIFlags) {
   2001   if (NumBytes == 0 && DestReg != BaseReg) {
   2002     BuildMI(MBB, MBBI, dl, TII.get(ARM::MOVr), DestReg)
   2003       .addReg(BaseReg, RegState::Kill)
   2004       .addImm((unsigned)Pred).addReg(PredReg).addReg(0)
   2005       .setMIFlags(MIFlags);
   2006     return;
   2007   }
   2008 
   2009   bool isSub = NumBytes < 0;
   2010   if (isSub) NumBytes = -NumBytes;
   2011 
   2012   while (NumBytes) {
   2013     unsigned RotAmt = ARM_AM::getSOImmValRotate(NumBytes);
   2014     unsigned ThisVal = NumBytes & ARM_AM::rotr32(0xFF, RotAmt);
   2015     assert(ThisVal && "Didn't extract field correctly");
   2016 
   2017     // We will handle these bits from offset, clear them.
   2018     NumBytes &= ~ThisVal;
   2019 
   2020     assert(ARM_AM::getSOImmVal(ThisVal) != -1 && "Bit extraction didn't work?");
   2021 
   2022     // Build the new ADD / SUB.
   2023     unsigned Opc = isSub ? ARM::SUBri : ARM::ADDri;
   2024     BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
   2025       .addReg(BaseReg, RegState::Kill).addImm(ThisVal)
   2026       .addImm((unsigned)Pred).addReg(PredReg).addReg(0)
   2027       .setMIFlags(MIFlags);
   2028     BaseReg = DestReg;
   2029   }
   2030 }
   2031 
   2032 bool llvm::tryFoldSPUpdateIntoPushPop(const ARMSubtarget &Subtarget,
   2033                                       MachineFunction &MF, MachineInstr *MI,
   2034                                       unsigned NumBytes) {
   2035   // This optimisation potentially adds lots of load and store
   2036   // micro-operations, it's only really a great benefit to code-size.
   2037   if (!MF.getFunction()->optForMinSize())
   2038     return false;
   2039 
   2040   // If only one register is pushed/popped, LLVM can use an LDR/STR
   2041   // instead. We can't modify those so make sure we're dealing with an
   2042   // instruction we understand.
   2043   bool IsPop = isPopOpcode(MI->getOpcode());
   2044   bool IsPush = isPushOpcode(MI->getOpcode());
   2045   if (!IsPush && !IsPop)
   2046     return false;
   2047 
   2048   bool IsVFPPushPop = MI->getOpcode() == ARM::VSTMDDB_UPD ||
   2049                       MI->getOpcode() == ARM::VLDMDIA_UPD;
   2050   bool IsT1PushPop = MI->getOpcode() == ARM::tPUSH ||
   2051                      MI->getOpcode() == ARM::tPOP ||
   2052                      MI->getOpcode() == ARM::tPOP_RET;
   2053 
   2054   assert((IsT1PushPop || (MI->getOperand(0).getReg() == ARM::SP &&
   2055                           MI->getOperand(1).getReg() == ARM::SP)) &&
   2056          "trying to fold sp update into non-sp-updating push/pop");
   2057 
   2058   // The VFP push & pop act on D-registers, so we can only fold an adjustment
   2059   // by a multiple of 8 bytes in correctly. Similarly rN is 4-bytes. Don't try
   2060   // if this is violated.
   2061   if (NumBytes % (IsVFPPushPop ? 8 : 4) != 0)
   2062     return false;
   2063 
   2064   // ARM and Thumb2 push/pop insts have explicit "sp, sp" operands (+
   2065   // pred) so the list starts at 4. Thumb1 starts after the predicate.
   2066   int RegListIdx = IsT1PushPop ? 2 : 4;
   2067 
   2068   // Calculate the space we'll need in terms of registers.
   2069   unsigned FirstReg = MI->getOperand(RegListIdx).getReg();
   2070   unsigned RD0Reg, RegsNeeded;
   2071   if (IsVFPPushPop) {
   2072     RD0Reg = ARM::D0;
   2073     RegsNeeded = NumBytes / 8;
   2074   } else {
   2075     RD0Reg = ARM::R0;
   2076     RegsNeeded = NumBytes / 4;
   2077   }
   2078 
   2079   // We're going to have to strip all list operands off before
   2080   // re-adding them since the order matters, so save the existing ones
   2081   // for later.
   2082   SmallVector<MachineOperand, 4> RegList;
   2083   for (int i = MI->getNumOperands() - 1; i >= RegListIdx; --i)
   2084     RegList.push_back(MI->getOperand(i));
   2085 
   2086   const TargetRegisterInfo *TRI = MF.getRegInfo().getTargetRegisterInfo();
   2087   const MCPhysReg *CSRegs = TRI->getCalleeSavedRegs(&MF);
   2088 
   2089   // Now try to find enough space in the reglist to allocate NumBytes.
   2090   for (unsigned CurReg = FirstReg - 1; CurReg >= RD0Reg && RegsNeeded;
   2091        --CurReg) {
   2092     if (!IsPop) {
   2093       // Pushing any register is completely harmless, mark the
   2094       // register involved as undef since we don't care about it in
   2095       // the slightest.
   2096       RegList.push_back(MachineOperand::CreateReg(CurReg, false, false,
   2097                                                   false, false, true));
   2098       --RegsNeeded;
   2099       continue;
   2100     }
   2101 
   2102     // However, we can only pop an extra register if it's not live. For
   2103     // registers live within the function we might clobber a return value
   2104     // register; the other way a register can be live here is if it's
   2105     // callee-saved.
   2106     if (isCalleeSavedRegister(CurReg, CSRegs) ||
   2107         MI->getParent()->computeRegisterLiveness(TRI, CurReg, MI) !=
   2108         MachineBasicBlock::LQR_Dead) {
   2109       // VFP pops don't allow holes in the register list, so any skip is fatal
   2110       // for our transformation. GPR pops do, so we should just keep looking.
   2111       if (IsVFPPushPop)
   2112         return false;
   2113       else
   2114         continue;
   2115     }
   2116 
   2117     // Mark the unimportant registers as <def,dead> in the POP.
   2118     RegList.push_back(MachineOperand::CreateReg(CurReg, true, false, false,
   2119                                                 true));
   2120     --RegsNeeded;
   2121   }
   2122 
   2123   if (RegsNeeded > 0)
   2124     return false;
   2125 
   2126   // Finally we know we can profitably perform the optimisation so go
   2127   // ahead: strip all existing registers off and add them back again
   2128   // in the right order.
   2129   for (int i = MI->getNumOperands() - 1; i >= RegListIdx; --i)
   2130     MI->RemoveOperand(i);
   2131 
   2132   // Add the complete list back in.
   2133   MachineInstrBuilder MIB(MF, &*MI);
   2134   for (int i = RegList.size() - 1; i >= 0; --i)
   2135     MIB.addOperand(RegList[i]);
   2136 
   2137   return true;
   2138 }
   2139 
   2140 bool llvm::rewriteARMFrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
   2141                                 unsigned FrameReg, int &Offset,
   2142                                 const ARMBaseInstrInfo &TII) {
   2143   unsigned Opcode = MI.getOpcode();
   2144   const MCInstrDesc &Desc = MI.getDesc();
   2145   unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
   2146   bool isSub = false;
   2147 
   2148   // Memory operands in inline assembly always use AddrMode2.
   2149   if (Opcode == ARM::INLINEASM)
   2150     AddrMode = ARMII::AddrMode2;
   2151 
   2152   if (Opcode == ARM::ADDri) {
   2153     Offset += MI.getOperand(FrameRegIdx+1).getImm();
   2154     if (Offset == 0) {
   2155       // Turn it into a move.
   2156       MI.setDesc(TII.get(ARM::MOVr));
   2157       MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
   2158       MI.RemoveOperand(FrameRegIdx+1);
   2159       Offset = 0;
   2160       return true;
   2161     } else if (Offset < 0) {
   2162       Offset = -Offset;
   2163       isSub = true;
   2164       MI.setDesc(TII.get(ARM::SUBri));
   2165     }
   2166 
   2167     // Common case: small offset, fits into instruction.
   2168     if (ARM_AM::getSOImmVal(Offset) != -1) {
   2169       // Replace the FrameIndex with sp / fp
   2170       MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
   2171       MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
   2172       Offset = 0;
   2173       return true;
   2174     }
   2175 
   2176     // Otherwise, pull as much of the immedidate into this ADDri/SUBri
   2177     // as possible.
   2178     unsigned RotAmt = ARM_AM::getSOImmValRotate(Offset);
   2179     unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xFF, RotAmt);
   2180 
   2181     // We will handle these bits from offset, clear them.
   2182     Offset &= ~ThisImmVal;
   2183 
   2184     // Get the properly encoded SOImmVal field.
   2185     assert(ARM_AM::getSOImmVal(ThisImmVal) != -1 &&
   2186            "Bit extraction didn't work?");
   2187     MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal);
   2188  } else {
   2189     unsigned ImmIdx = 0;
   2190     int InstrOffs = 0;
   2191     unsigned NumBits = 0;
   2192     unsigned Scale = 1;
   2193     switch (AddrMode) {
   2194     case ARMII::AddrMode_i12: {
   2195       ImmIdx = FrameRegIdx + 1;
   2196       InstrOffs = MI.getOperand(ImmIdx).getImm();
   2197       NumBits = 12;
   2198       break;
   2199     }
   2200     case ARMII::AddrMode2: {
   2201       ImmIdx = FrameRegIdx+2;
   2202       InstrOffs = ARM_AM::getAM2Offset(MI.getOperand(ImmIdx).getImm());
   2203       if (ARM_AM::getAM2Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub)
   2204         InstrOffs *= -1;
   2205       NumBits = 12;
   2206       break;
   2207     }
   2208     case ARMII::AddrMode3: {
   2209       ImmIdx = FrameRegIdx+2;
   2210       InstrOffs = ARM_AM::getAM3Offset(MI.getOperand(ImmIdx).getImm());
   2211       if (ARM_AM::getAM3Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub)
   2212         InstrOffs *= -1;
   2213       NumBits = 8;
   2214       break;
   2215     }
   2216     case ARMII::AddrMode4:
   2217     case ARMII::AddrMode6:
   2218       // Can't fold any offset even if it's zero.
   2219       return false;
   2220     case ARMII::AddrMode5: {
   2221       ImmIdx = FrameRegIdx+1;
   2222       InstrOffs = ARM_AM::getAM5Offset(MI.getOperand(ImmIdx).getImm());
   2223       if (ARM_AM::getAM5Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub)
   2224         InstrOffs *= -1;
   2225       NumBits = 8;
   2226       Scale = 4;
   2227       break;
   2228     }
   2229     default:
   2230       llvm_unreachable("Unsupported addressing mode!");
   2231     }
   2232 
   2233     Offset += InstrOffs * Scale;
   2234     assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!");
   2235     if (Offset < 0) {
   2236       Offset = -Offset;
   2237       isSub = true;
   2238     }
   2239 
   2240     // Attempt to fold address comp. if opcode has offset bits
   2241     if (NumBits > 0) {
   2242       // Common case: small offset, fits into instruction.
   2243       MachineOperand &ImmOp = MI.getOperand(ImmIdx);
   2244       int ImmedOffset = Offset / Scale;
   2245       unsigned Mask = (1 << NumBits) - 1;
   2246       if ((unsigned)Offset <= Mask * Scale) {
   2247         // Replace the FrameIndex with sp
   2248         MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
   2249         // FIXME: When addrmode2 goes away, this will simplify (like the
   2250         // T2 version), as the LDR.i12 versions don't need the encoding
   2251         // tricks for the offset value.
   2252         if (isSub) {
   2253           if (AddrMode == ARMII::AddrMode_i12)
   2254             ImmedOffset = -ImmedOffset;
   2255           else
   2256             ImmedOffset |= 1 << NumBits;
   2257         }
   2258         ImmOp.ChangeToImmediate(ImmedOffset);
   2259         Offset = 0;
   2260         return true;
   2261       }
   2262 
   2263       // Otherwise, it didn't fit. Pull in what we can to simplify the immed.
   2264       ImmedOffset = ImmedOffset & Mask;
   2265       if (isSub) {
   2266         if (AddrMode == ARMII::AddrMode_i12)
   2267           ImmedOffset = -ImmedOffset;
   2268         else
   2269           ImmedOffset |= 1 << NumBits;
   2270       }
   2271       ImmOp.ChangeToImmediate(ImmedOffset);
   2272       Offset &= ~(Mask*Scale);
   2273     }
   2274   }
   2275 
   2276   Offset = (isSub) ? -Offset : Offset;
   2277   return Offset == 0;
   2278 }
   2279 
   2280 /// analyzeCompare - For a comparison instruction, return the source registers
   2281 /// in SrcReg and SrcReg2 if having two register operands, and the value it
   2282 /// compares against in CmpValue. Return true if the comparison instruction
   2283 /// can be analyzed.
   2284 bool ARMBaseInstrInfo::
   2285 analyzeCompare(const MachineInstr *MI, unsigned &SrcReg, unsigned &SrcReg2,
   2286                int &CmpMask, int &CmpValue) const {
   2287   switch (MI->getOpcode()) {
   2288   default: break;
   2289   case ARM::CMPri:
   2290   case ARM::t2CMPri:
   2291     SrcReg = MI->getOperand(0).getReg();
   2292     SrcReg2 = 0;
   2293     CmpMask = ~0;
   2294     CmpValue = MI->getOperand(1).getImm();
   2295     return true;
   2296   case ARM::CMPrr:
   2297   case ARM::t2CMPrr:
   2298     SrcReg = MI->getOperand(0).getReg();
   2299     SrcReg2 = MI->getOperand(1).getReg();
   2300     CmpMask = ~0;
   2301     CmpValue = 0;
   2302     return true;
   2303   case ARM::TSTri:
   2304   case ARM::t2TSTri:
   2305     SrcReg = MI->getOperand(0).getReg();
   2306     SrcReg2 = 0;
   2307     CmpMask = MI->getOperand(1).getImm();
   2308     CmpValue = 0;
   2309     return true;
   2310   }
   2311 
   2312   return false;
   2313 }
   2314 
   2315 /// isSuitableForMask - Identify a suitable 'and' instruction that
   2316 /// operates on the given source register and applies the same mask
   2317 /// as a 'tst' instruction. Provide a limited look-through for copies.
   2318 /// When successful, MI will hold the found instruction.
   2319 static bool isSuitableForMask(MachineInstr *&MI, unsigned SrcReg,
   2320                               int CmpMask, bool CommonUse) {
   2321   switch (MI->getOpcode()) {
   2322     case ARM::ANDri:
   2323     case ARM::t2ANDri:
   2324       if (CmpMask != MI->getOperand(2).getImm())
   2325         return false;
   2326       if (SrcReg == MI->getOperand(CommonUse ? 1 : 0).getReg())
   2327         return true;
   2328       break;
   2329   }
   2330 
   2331   return false;
   2332 }
   2333 
   2334 /// getSwappedCondition - assume the flags are set by MI(a,b), return
   2335 /// the condition code if we modify the instructions such that flags are
   2336 /// set by MI(b,a).
   2337 inline static ARMCC::CondCodes getSwappedCondition(ARMCC::CondCodes CC) {
   2338   switch (CC) {
   2339   default: return ARMCC::AL;
   2340   case ARMCC::EQ: return ARMCC::EQ;
   2341   case ARMCC::NE: return ARMCC::NE;
   2342   case ARMCC::HS: return ARMCC::LS;
   2343   case ARMCC::LO: return ARMCC::HI;
   2344   case ARMCC::HI: return ARMCC::LO;
   2345   case ARMCC::LS: return ARMCC::HS;
   2346   case ARMCC::GE: return ARMCC::LE;
   2347   case ARMCC::LT: return ARMCC::GT;
   2348   case ARMCC::GT: return ARMCC::LT;
   2349   case ARMCC::LE: return ARMCC::GE;
   2350   }
   2351 }
   2352 
   2353 /// isRedundantFlagInstr - check whether the first instruction, whose only
   2354 /// purpose is to update flags, can be made redundant.
   2355 /// CMPrr can be made redundant by SUBrr if the operands are the same.
   2356 /// CMPri can be made redundant by SUBri if the operands are the same.
   2357 /// This function can be extended later on.
   2358 inline static bool isRedundantFlagInstr(MachineInstr *CmpI, unsigned SrcReg,
   2359                                         unsigned SrcReg2, int ImmValue,
   2360                                         MachineInstr *OI) {
   2361   if ((CmpI->getOpcode() == ARM::CMPrr ||
   2362        CmpI->getOpcode() == ARM::t2CMPrr) &&
   2363       (OI->getOpcode() == ARM::SUBrr ||
   2364        OI->getOpcode() == ARM::t2SUBrr) &&
   2365       ((OI->getOperand(1).getReg() == SrcReg &&
   2366         OI->getOperand(2).getReg() == SrcReg2) ||
   2367        (OI->getOperand(1).getReg() == SrcReg2 &&
   2368         OI->getOperand(2).getReg() == SrcReg)))
   2369     return true;
   2370 
   2371   if ((CmpI->getOpcode() == ARM::CMPri ||
   2372        CmpI->getOpcode() == ARM::t2CMPri) &&
   2373       (OI->getOpcode() == ARM::SUBri ||
   2374        OI->getOpcode() == ARM::t2SUBri) &&
   2375       OI->getOperand(1).getReg() == SrcReg &&
   2376       OI->getOperand(2).getImm() == ImmValue)
   2377     return true;
   2378   return false;
   2379 }
   2380 
   2381 /// optimizeCompareInstr - Convert the instruction supplying the argument to the
   2382 /// comparison into one that sets the zero bit in the flags register;
   2383 /// Remove a redundant Compare instruction if an earlier instruction can set the
   2384 /// flags in the same way as Compare.
   2385 /// E.g. SUBrr(r1,r2) and CMPrr(r1,r2). We also handle the case where two
   2386 /// operands are swapped: SUBrr(r1,r2) and CMPrr(r2,r1), by updating the
   2387 /// condition code of instructions which use the flags.
   2388 bool ARMBaseInstrInfo::
   2389 optimizeCompareInstr(MachineInstr *CmpInstr, unsigned SrcReg, unsigned SrcReg2,
   2390                      int CmpMask, int CmpValue,
   2391                      const MachineRegisterInfo *MRI) const {
   2392   // Get the unique definition of SrcReg.
   2393   MachineInstr *MI = MRI->getUniqueVRegDef(SrcReg);
   2394   if (!MI) return false;
   2395 
   2396   // Masked compares sometimes use the same register as the corresponding 'and'.
   2397   if (CmpMask != ~0) {
   2398     if (!isSuitableForMask(MI, SrcReg, CmpMask, false) || isPredicated(MI)) {
   2399       MI = nullptr;
   2400       for (MachineRegisterInfo::use_instr_iterator
   2401            UI = MRI->use_instr_begin(SrcReg), UE = MRI->use_instr_end();
   2402            UI != UE; ++UI) {
   2403         if (UI->getParent() != CmpInstr->getParent()) continue;
   2404         MachineInstr *PotentialAND = &*UI;
   2405         if (!isSuitableForMask(PotentialAND, SrcReg, CmpMask, true) ||
   2406             isPredicated(PotentialAND))
   2407           continue;
   2408         MI = PotentialAND;
   2409         break;
   2410       }
   2411       if (!MI) return false;
   2412     }
   2413   }
   2414 
   2415   // Get ready to iterate backward from CmpInstr.
   2416   MachineBasicBlock::iterator I = CmpInstr, E = MI,
   2417                               B = CmpInstr->getParent()->begin();
   2418 
   2419   // Early exit if CmpInstr is at the beginning of the BB.
   2420   if (I == B) return false;
   2421 
   2422   // There are two possible candidates which can be changed to set CPSR:
   2423   // One is MI, the other is a SUB instruction.
   2424   // For CMPrr(r1,r2), we are looking for SUB(r1,r2) or SUB(r2,r1).
   2425   // For CMPri(r1, CmpValue), we are looking for SUBri(r1, CmpValue).
   2426   MachineInstr *Sub = nullptr;
   2427   if (SrcReg2 != 0)
   2428     // MI is not a candidate for CMPrr.
   2429     MI = nullptr;
   2430   else if (MI->getParent() != CmpInstr->getParent() || CmpValue != 0) {
   2431     // Conservatively refuse to convert an instruction which isn't in the same
   2432     // BB as the comparison.
   2433     // For CMPri w/ CmpValue != 0, a Sub may still be a candidate.
   2434     // Thus we cannot return here.
   2435     if (CmpInstr->getOpcode() == ARM::CMPri ||
   2436        CmpInstr->getOpcode() == ARM::t2CMPri)
   2437       MI = nullptr;
   2438     else
   2439       return false;
   2440   }
   2441 
   2442   // Check that CPSR isn't set between the comparison instruction and the one we
   2443   // want to change. At the same time, search for Sub.
   2444   const TargetRegisterInfo *TRI = &getRegisterInfo();
   2445   --I;
   2446   for (; I != E; --I) {
   2447     const MachineInstr &Instr = *I;
   2448 
   2449     if (Instr.modifiesRegister(ARM::CPSR, TRI) ||
   2450         Instr.readsRegister(ARM::CPSR, TRI))
   2451       // This instruction modifies or uses CPSR after the one we want to
   2452       // change. We can't do this transformation.
   2453       return false;
   2454 
   2455     // Check whether CmpInstr can be made redundant by the current instruction.
   2456     if (isRedundantFlagInstr(CmpInstr, SrcReg, SrcReg2, CmpValue, &*I)) {
   2457       Sub = &*I;
   2458       break;
   2459     }
   2460 
   2461     if (I == B)
   2462       // The 'and' is below the comparison instruction.
   2463       return false;
   2464   }
   2465 
   2466   // Return false if no candidates exist.
   2467   if (!MI && !Sub)
   2468     return false;
   2469 
   2470   // The single candidate is called MI.
   2471   if (!MI) MI = Sub;
   2472 
   2473   // We can't use a predicated instruction - it doesn't always write the flags.
   2474   if (isPredicated(MI))
   2475     return false;
   2476 
   2477   switch (MI->getOpcode()) {
   2478   default: break;
   2479   case ARM::RSBrr:
   2480   case ARM::RSBri:
   2481   case ARM::RSCrr:
   2482   case ARM::RSCri:
   2483   case ARM::ADDrr:
   2484   case ARM::ADDri:
   2485   case ARM::ADCrr:
   2486   case ARM::ADCri:
   2487   case ARM::SUBrr:
   2488   case ARM::SUBri:
   2489   case ARM::SBCrr:
   2490   case ARM::SBCri:
   2491   case ARM::t2RSBri:
   2492   case ARM::t2ADDrr:
   2493   case ARM::t2ADDri:
   2494   case ARM::t2ADCrr:
   2495   case ARM::t2ADCri:
   2496   case ARM::t2SUBrr:
   2497   case ARM::t2SUBri:
   2498   case ARM::t2SBCrr:
   2499   case ARM::t2SBCri:
   2500   case ARM::ANDrr:
   2501   case ARM::ANDri:
   2502   case ARM::t2ANDrr:
   2503   case ARM::t2ANDri:
   2504   case ARM::ORRrr:
   2505   case ARM::ORRri:
   2506   case ARM::t2ORRrr:
   2507   case ARM::t2ORRri:
   2508   case ARM::EORrr:
   2509   case ARM::EORri:
   2510   case ARM::t2EORrr:
   2511   case ARM::t2EORri: {
   2512     // Scan forward for the use of CPSR
   2513     // When checking against MI: if it's a conditional code that requires
   2514     // checking of the V bit or C bit, then this is not safe to do.
   2515     // It is safe to remove CmpInstr if CPSR is redefined or killed.
   2516     // If we are done with the basic block, we need to check whether CPSR is
   2517     // live-out.
   2518     SmallVector<std::pair<MachineOperand*, ARMCC::CondCodes>, 4>
   2519         OperandsToUpdate;
   2520     bool isSafe = false;
   2521     I = CmpInstr;
   2522     E = CmpInstr->getParent()->end();
   2523     while (!isSafe && ++I != E) {
   2524       const MachineInstr &Instr = *I;
   2525       for (unsigned IO = 0, EO = Instr.getNumOperands();
   2526            !isSafe && IO != EO; ++IO) {
   2527         const MachineOperand &MO = Instr.getOperand(IO);
   2528         if (MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) {
   2529           isSafe = true;
   2530           break;
   2531         }
   2532         if (!MO.isReg() || MO.getReg() != ARM::CPSR)
   2533           continue;
   2534         if (MO.isDef()) {
   2535           isSafe = true;
   2536           break;
   2537         }
   2538         // Condition code is after the operand before CPSR except for VSELs.
   2539         ARMCC::CondCodes CC;
   2540         bool IsInstrVSel = true;
   2541         switch (Instr.getOpcode()) {
   2542         default:
   2543           IsInstrVSel = false;
   2544           CC = (ARMCC::CondCodes)Instr.getOperand(IO - 1).getImm();
   2545           break;
   2546         case ARM::VSELEQD:
   2547         case ARM::VSELEQS:
   2548           CC = ARMCC::EQ;
   2549           break;
   2550         case ARM::VSELGTD:
   2551         case ARM::VSELGTS:
   2552           CC = ARMCC::GT;
   2553           break;
   2554         case ARM::VSELGED:
   2555         case ARM::VSELGES:
   2556           CC = ARMCC::GE;
   2557           break;
   2558         case ARM::VSELVSS:
   2559         case ARM::VSELVSD:
   2560           CC = ARMCC::VS;
   2561           break;
   2562         }
   2563 
   2564         if (Sub) {
   2565           ARMCC::CondCodes NewCC = getSwappedCondition(CC);
   2566           if (NewCC == ARMCC::AL)
   2567             return false;
   2568           // If we have SUB(r1, r2) and CMP(r2, r1), the condition code based
   2569           // on CMP needs to be updated to be based on SUB.
   2570           // Push the condition code operands to OperandsToUpdate.
   2571           // If it is safe to remove CmpInstr, the condition code of these
   2572           // operands will be modified.
   2573           if (SrcReg2 != 0 && Sub->getOperand(1).getReg() == SrcReg2 &&
   2574               Sub->getOperand(2).getReg() == SrcReg) {
   2575             // VSel doesn't support condition code update.
   2576             if (IsInstrVSel)
   2577               return false;
   2578             OperandsToUpdate.push_back(
   2579                 std::make_pair(&((*I).getOperand(IO - 1)), NewCC));
   2580           }
   2581         } else {
   2582           // No Sub, so this is x = <op> y, z; cmp x, 0.
   2583           switch (CC) {
   2584           case ARMCC::EQ: // Z
   2585           case ARMCC::NE: // Z
   2586           case ARMCC::MI: // N
   2587           case ARMCC::PL: // N
   2588           case ARMCC::AL: // none
   2589             // CPSR can be used multiple times, we should continue.
   2590             break;
   2591           case ARMCC::HS: // C
   2592           case ARMCC::LO: // C
   2593           case ARMCC::VS: // V
   2594           case ARMCC::VC: // V
   2595           case ARMCC::HI: // C Z
   2596           case ARMCC::LS: // C Z
   2597           case ARMCC::GE: // N V
   2598           case ARMCC::LT: // N V
   2599           case ARMCC::GT: // Z N V
   2600           case ARMCC::LE: // Z N V
   2601             // The instruction uses the V bit or C bit which is not safe.
   2602             return false;
   2603           }
   2604         }
   2605       }
   2606     }
   2607 
   2608     // If CPSR is not killed nor re-defined, we should check whether it is
   2609     // live-out. If it is live-out, do not optimize.
   2610     if (!isSafe) {
   2611       MachineBasicBlock *MBB = CmpInstr->getParent();
   2612       for (MachineBasicBlock::succ_iterator SI = MBB->succ_begin(),
   2613                SE = MBB->succ_end(); SI != SE; ++SI)
   2614         if ((*SI)->isLiveIn(ARM::CPSR))
   2615           return false;
   2616     }
   2617 
   2618     // Toggle the optional operand to CPSR.
   2619     MI->getOperand(5).setReg(ARM::CPSR);
   2620     MI->getOperand(5).setIsDef(true);
   2621     assert(!isPredicated(MI) && "Can't use flags from predicated instruction");
   2622     CmpInstr->eraseFromParent();
   2623 
   2624     // Modify the condition code of operands in OperandsToUpdate.
   2625     // Since we have SUB(r1, r2) and CMP(r2, r1), the condition code needs to
   2626     // be changed from r2 > r1 to r1 < r2, from r2 < r1 to r1 > r2, etc.
   2627     for (unsigned i = 0, e = OperandsToUpdate.size(); i < e; i++)
   2628       OperandsToUpdate[i].first->setImm(OperandsToUpdate[i].second);
   2629     return true;
   2630   }
   2631   }
   2632 
   2633   return false;
   2634 }
   2635 
   2636 bool ARMBaseInstrInfo::FoldImmediate(MachineInstr *UseMI,
   2637                                      MachineInstr *DefMI, unsigned Reg,
   2638                                      MachineRegisterInfo *MRI) const {
   2639   // Fold large immediates into add, sub, or, xor.
   2640   unsigned DefOpc = DefMI->getOpcode();
   2641   if (DefOpc != ARM::t2MOVi32imm && DefOpc != ARM::MOVi32imm)
   2642     return false;
   2643   if (!DefMI->getOperand(1).isImm())
   2644     // Could be t2MOVi32imm <ga:xx>
   2645     return false;
   2646 
   2647   if (!MRI->hasOneNonDBGUse(Reg))
   2648     return false;
   2649 
   2650   const MCInstrDesc &DefMCID = DefMI->getDesc();
   2651   if (DefMCID.hasOptionalDef()) {
   2652     unsigned NumOps = DefMCID.getNumOperands();
   2653     const MachineOperand &MO = DefMI->getOperand(NumOps-1);
   2654     if (MO.getReg() == ARM::CPSR && !MO.isDead())
   2655       // If DefMI defines CPSR and it is not dead, it's obviously not safe
   2656       // to delete DefMI.
   2657       return false;
   2658   }
   2659 
   2660   const MCInstrDesc &UseMCID = UseMI->getDesc();
   2661   if (UseMCID.hasOptionalDef()) {
   2662     unsigned NumOps = UseMCID.getNumOperands();
   2663     if (UseMI->getOperand(NumOps-1).getReg() == ARM::CPSR)
   2664       // If the instruction sets the flag, do not attempt this optimization
   2665       // since it may change the semantics of the code.
   2666       return false;
   2667   }
   2668 
   2669   unsigned UseOpc = UseMI->getOpcode();
   2670   unsigned NewUseOpc = 0;
   2671   uint32_t ImmVal = (uint32_t)DefMI->getOperand(1).getImm();
   2672   uint32_t SOImmValV1 = 0, SOImmValV2 = 0;
   2673   bool Commute = false;
   2674   switch (UseOpc) {
   2675   default: return false;
   2676   case ARM::SUBrr:
   2677   case ARM::ADDrr:
   2678   case ARM::ORRrr:
   2679   case ARM::EORrr:
   2680   case ARM::t2SUBrr:
   2681   case ARM::t2ADDrr:
   2682   case ARM::t2ORRrr:
   2683   case ARM::t2EORrr: {
   2684     Commute = UseMI->getOperand(2).getReg() != Reg;
   2685     switch (UseOpc) {
   2686     default: break;
   2687     case ARM::SUBrr: {
   2688       if (Commute)
   2689         return false;
   2690       ImmVal = -ImmVal;
   2691       NewUseOpc = ARM::SUBri;
   2692       // Fallthrough
   2693     }
   2694     case ARM::ADDrr:
   2695     case ARM::ORRrr:
   2696     case ARM::EORrr: {
   2697       if (!ARM_AM::isSOImmTwoPartVal(ImmVal))
   2698         return false;
   2699       SOImmValV1 = (uint32_t)ARM_AM::getSOImmTwoPartFirst(ImmVal);
   2700       SOImmValV2 = (uint32_t)ARM_AM::getSOImmTwoPartSecond(ImmVal);
   2701       switch (UseOpc) {
   2702       default: break;
   2703       case ARM::ADDrr: NewUseOpc = ARM::ADDri; break;
   2704       case ARM::ORRrr: NewUseOpc = ARM::ORRri; break;
   2705       case ARM::EORrr: NewUseOpc = ARM::EORri; break;
   2706       }
   2707       break;
   2708     }
   2709     case ARM::t2SUBrr: {
   2710       if (Commute)
   2711         return false;
   2712       ImmVal = -ImmVal;
   2713       NewUseOpc = ARM::t2SUBri;
   2714       // Fallthrough
   2715     }
   2716     case ARM::t2ADDrr:
   2717     case ARM::t2ORRrr:
   2718     case ARM::t2EORrr: {
   2719       if (!ARM_AM::isT2SOImmTwoPartVal(ImmVal))
   2720         return false;
   2721       SOImmValV1 = (uint32_t)ARM_AM::getT2SOImmTwoPartFirst(ImmVal);
   2722       SOImmValV2 = (uint32_t)ARM_AM::getT2SOImmTwoPartSecond(ImmVal);
   2723       switch (UseOpc) {
   2724       default: break;
   2725       case ARM::t2ADDrr: NewUseOpc = ARM::t2ADDri; break;
   2726       case ARM::t2ORRrr: NewUseOpc = ARM::t2ORRri; break;
   2727       case ARM::t2EORrr: NewUseOpc = ARM::t2EORri; break;
   2728       }
   2729       break;
   2730     }
   2731     }
   2732   }
   2733   }
   2734 
   2735   unsigned OpIdx = Commute ? 2 : 1;
   2736   unsigned Reg1 = UseMI->getOperand(OpIdx).getReg();
   2737   bool isKill = UseMI->getOperand(OpIdx).isKill();
   2738   unsigned NewReg = MRI->createVirtualRegister(MRI->getRegClass(Reg));
   2739   AddDefaultCC(AddDefaultPred(BuildMI(*UseMI->getParent(),
   2740                                       UseMI, UseMI->getDebugLoc(),
   2741                                       get(NewUseOpc), NewReg)
   2742                               .addReg(Reg1, getKillRegState(isKill))
   2743                               .addImm(SOImmValV1)));
   2744   UseMI->setDesc(get(NewUseOpc));
   2745   UseMI->getOperand(1).setReg(NewReg);
   2746   UseMI->getOperand(1).setIsKill();
   2747   UseMI->getOperand(2).ChangeToImmediate(SOImmValV2);
   2748   DefMI->eraseFromParent();
   2749   return true;
   2750 }
   2751 
   2752 static unsigned getNumMicroOpsSwiftLdSt(const InstrItineraryData *ItinData,
   2753                                         const MachineInstr *MI) {
   2754   switch (MI->getOpcode()) {
   2755   default: {
   2756     const MCInstrDesc &Desc = MI->getDesc();
   2757     int UOps = ItinData->getNumMicroOps(Desc.getSchedClass());
   2758     assert(UOps >= 0 && "bad # UOps");
   2759     return UOps;
   2760   }
   2761 
   2762   case ARM::LDRrs:
   2763   case ARM::LDRBrs:
   2764   case ARM::STRrs:
   2765   case ARM::STRBrs: {
   2766     unsigned ShOpVal = MI->getOperand(3).getImm();
   2767     bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
   2768     unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
   2769     if (!isSub &&
   2770         (ShImm == 0 ||
   2771          ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
   2772           ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
   2773       return 1;
   2774     return 2;
   2775   }
   2776 
   2777   case ARM::LDRH:
   2778   case ARM::STRH: {
   2779     if (!MI->getOperand(2).getReg())
   2780       return 1;
   2781 
   2782     unsigned ShOpVal = MI->getOperand(3).getImm();
   2783     bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
   2784     unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
   2785     if (!isSub &&
   2786         (ShImm == 0 ||
   2787          ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
   2788           ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
   2789       return 1;
   2790     return 2;
   2791   }
   2792 
   2793   case ARM::LDRSB:
   2794   case ARM::LDRSH:
   2795     return (ARM_AM::getAM3Op(MI->getOperand(3).getImm()) == ARM_AM::sub) ? 3:2;
   2796 
   2797   case ARM::LDRSB_POST:
   2798   case ARM::LDRSH_POST: {
   2799     unsigned Rt = MI->getOperand(0).getReg();
   2800     unsigned Rm = MI->getOperand(3).getReg();
   2801     return (Rt == Rm) ? 4 : 3;
   2802   }
   2803 
   2804   case ARM::LDR_PRE_REG:
   2805   case ARM::LDRB_PRE_REG: {
   2806     unsigned Rt = MI->getOperand(0).getReg();
   2807     unsigned Rm = MI->getOperand(3).getReg();
   2808     if (Rt == Rm)
   2809       return 3;
   2810     unsigned ShOpVal = MI->getOperand(4).getImm();
   2811     bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
   2812     unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
   2813     if (!isSub &&
   2814         (ShImm == 0 ||
   2815          ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
   2816           ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
   2817       return 2;
   2818     return 3;
   2819   }
   2820 
   2821   case ARM::STR_PRE_REG:
   2822   case ARM::STRB_PRE_REG: {
   2823     unsigned ShOpVal = MI->getOperand(4).getImm();
   2824     bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
   2825     unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
   2826     if (!isSub &&
   2827         (ShImm == 0 ||
   2828          ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
   2829           ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
   2830       return 2;
   2831     return 3;
   2832   }
   2833 
   2834   case ARM::LDRH_PRE:
   2835   case ARM::STRH_PRE: {
   2836     unsigned Rt = MI->getOperand(0).getReg();
   2837     unsigned Rm = MI->getOperand(3).getReg();
   2838     if (!Rm)
   2839       return 2;
   2840     if (Rt == Rm)
   2841       return 3;
   2842     return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub)
   2843       ? 3 : 2;
   2844   }
   2845 
   2846   case ARM::LDR_POST_REG:
   2847   case ARM::LDRB_POST_REG:
   2848   case ARM::LDRH_POST: {
   2849     unsigned Rt = MI->getOperand(0).getReg();
   2850     unsigned Rm = MI->getOperand(3).getReg();
   2851     return (Rt == Rm) ? 3 : 2;
   2852   }
   2853 
   2854   case ARM::LDR_PRE_IMM:
   2855   case ARM::LDRB_PRE_IMM:
   2856   case ARM::LDR_POST_IMM:
   2857   case ARM::LDRB_POST_IMM:
   2858   case ARM::STRB_POST_IMM:
   2859   case ARM::STRB_POST_REG:
   2860   case ARM::STRB_PRE_IMM:
   2861   case ARM::STRH_POST:
   2862   case ARM::STR_POST_IMM:
   2863   case ARM::STR_POST_REG:
   2864   case ARM::STR_PRE_IMM:
   2865     return 2;
   2866 
   2867   case ARM::LDRSB_PRE:
   2868   case ARM::LDRSH_PRE: {
   2869     unsigned Rm = MI->getOperand(3).getReg();
   2870     if (Rm == 0)
   2871       return 3;
   2872     unsigned Rt = MI->getOperand(0).getReg();
   2873     if (Rt == Rm)
   2874       return 4;
   2875     unsigned ShOpVal = MI->getOperand(4).getImm();
   2876     bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
   2877     unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
   2878     if (!isSub &&
   2879         (ShImm == 0 ||
   2880          ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
   2881           ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
   2882       return 3;
   2883     return 4;
   2884   }
   2885 
   2886   case ARM::LDRD: {
   2887     unsigned Rt = MI->getOperand(0).getReg();
   2888     unsigned Rn = MI->getOperand(2).getReg();
   2889     unsigned Rm = MI->getOperand(3).getReg();
   2890     if (Rm)
   2891       return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ?4:3;
   2892     return (Rt == Rn) ? 3 : 2;
   2893   }
   2894 
   2895   case ARM::STRD: {
   2896     unsigned Rm = MI->getOperand(3).getReg();
   2897     if (Rm)
   2898       return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ?4:3;
   2899     return 2;
   2900   }
   2901 
   2902   case ARM::LDRD_POST:
   2903   case ARM::t2LDRD_POST:
   2904     return 3;
   2905 
   2906   case ARM::STRD_POST:
   2907   case ARM::t2STRD_POST:
   2908     return 4;
   2909 
   2910   case ARM::LDRD_PRE: {
   2911     unsigned Rt = MI->getOperand(0).getReg();
   2912     unsigned Rn = MI->getOperand(3).getReg();
   2913     unsigned Rm = MI->getOperand(4).getReg();
   2914     if (Rm)
   2915       return (ARM_AM::getAM3Op(MI->getOperand(5).getImm()) == ARM_AM::sub) ?5:4;
   2916     return (Rt == Rn) ? 4 : 3;
   2917   }
   2918 
   2919   case ARM::t2LDRD_PRE: {
   2920     unsigned Rt = MI->getOperand(0).getReg();
   2921     unsigned Rn = MI->getOperand(3).getReg();
   2922     return (Rt == Rn) ? 4 : 3;
   2923   }
   2924 
   2925   case ARM::STRD_PRE: {
   2926     unsigned Rm = MI->getOperand(4).getReg();
   2927     if (Rm)
   2928       return (ARM_AM::getAM3Op(MI->getOperand(5).getImm()) == ARM_AM::sub) ?5:4;
   2929     return 3;
   2930   }
   2931 
   2932   case ARM::t2STRD_PRE:
   2933     return 3;
   2934 
   2935   case ARM::t2LDR_POST:
   2936   case ARM::t2LDRB_POST:
   2937   case ARM::t2LDRB_PRE:
   2938   case ARM::t2LDRSBi12:
   2939   case ARM::t2LDRSBi8:
   2940   case ARM::t2LDRSBpci:
   2941   case ARM::t2LDRSBs:
   2942   case ARM::t2LDRH_POST:
   2943   case ARM::t2LDRH_PRE:
   2944   case ARM::t2LDRSBT:
   2945   case ARM::t2LDRSB_POST:
   2946   case ARM::t2LDRSB_PRE:
   2947   case ARM::t2LDRSH_POST:
   2948   case ARM::t2LDRSH_PRE:
   2949   case ARM::t2LDRSHi12:
   2950   case ARM::t2LDRSHi8:
   2951   case ARM::t2LDRSHpci:
   2952   case ARM::t2LDRSHs:
   2953     return 2;
   2954 
   2955   case ARM::t2LDRDi8: {
   2956     unsigned Rt = MI->getOperand(0).getReg();
   2957     unsigned Rn = MI->getOperand(2).getReg();
   2958     return (Rt == Rn) ? 3 : 2;
   2959   }
   2960 
   2961   case ARM::t2STRB_POST:
   2962   case ARM::t2STRB_PRE:
   2963   case ARM::t2STRBs:
   2964   case ARM::t2STRDi8:
   2965   case ARM::t2STRH_POST:
   2966   case ARM::t2STRH_PRE:
   2967   case ARM::t2STRHs:
   2968   case ARM::t2STR_POST:
   2969   case ARM::t2STR_PRE:
   2970   case ARM::t2STRs:
   2971     return 2;
   2972   }
   2973 }
   2974 
   2975 // Return the number of 32-bit words loaded by LDM or stored by STM. If this
   2976 // can't be easily determined return 0 (missing MachineMemOperand).
   2977 //
   2978 // FIXME: The current MachineInstr design does not support relying on machine
   2979 // mem operands to determine the width of a memory access. Instead, we expect
   2980 // the target to provide this information based on the instruction opcode and
   2981 // operands. However, using MachineMemOperand is the best solution now for
   2982 // two reasons:
   2983 //
   2984 // 1) getNumMicroOps tries to infer LDM memory width from the total number of MI
   2985 // operands. This is much more dangerous than using the MachineMemOperand
   2986 // sizes because CodeGen passes can insert/remove optional machine operands. In
   2987 // fact, it's totally incorrect for preRA passes and appears to be wrong for
   2988 // postRA passes as well.
   2989 //
   2990 // 2) getNumLDMAddresses is only used by the scheduling machine model and any
   2991 // machine model that calls this should handle the unknown (zero size) case.
   2992 //
   2993 // Long term, we should require a target hook that verifies MachineMemOperand
   2994 // sizes during MC lowering. That target hook should be local to MC lowering
   2995 // because we can't ensure that it is aware of other MI forms. Doing this will
   2996 // ensure that MachineMemOperands are correctly propagated through all passes.
   2997 unsigned ARMBaseInstrInfo::getNumLDMAddresses(const MachineInstr *MI) const {
   2998   unsigned Size = 0;
   2999   for (MachineInstr::mmo_iterator I = MI->memoperands_begin(),
   3000          E = MI->memoperands_end(); I != E; ++I) {
   3001     Size += (*I)->getSize();
   3002   }
   3003   return Size / 4;
   3004 }
   3005 
   3006 unsigned
   3007 ARMBaseInstrInfo::getNumMicroOps(const InstrItineraryData *ItinData,
   3008                                  const MachineInstr *MI) const {
   3009   if (!ItinData || ItinData->isEmpty())
   3010     return 1;
   3011 
   3012   const MCInstrDesc &Desc = MI->getDesc();
   3013   unsigned Class = Desc.getSchedClass();
   3014   int ItinUOps = ItinData->getNumMicroOps(Class);
   3015   if (ItinUOps >= 0) {
   3016     if (Subtarget.isSwift() && (Desc.mayLoad() || Desc.mayStore()))
   3017       return getNumMicroOpsSwiftLdSt(ItinData, MI);
   3018 
   3019     return ItinUOps;
   3020   }
   3021 
   3022   unsigned Opc = MI->getOpcode();
   3023   switch (Opc) {
   3024   default:
   3025     llvm_unreachable("Unexpected multi-uops instruction!");
   3026   case ARM::VLDMQIA:
   3027   case ARM::VSTMQIA:
   3028     return 2;
   3029 
   3030   // The number of uOps for load / store multiple are determined by the number
   3031   // registers.
   3032   //
   3033   // On Cortex-A8, each pair of register loads / stores can be scheduled on the
   3034   // same cycle. The scheduling for the first load / store must be done
   3035   // separately by assuming the address is not 64-bit aligned.
   3036   //
   3037   // On Cortex-A9, the formula is simply (#reg / 2) + (#reg % 2). If the address
   3038   // is not 64-bit aligned, then AGU would take an extra cycle.  For VFP / NEON
   3039   // load / store multiple, the formula is (#reg / 2) + (#reg % 2) + 1.
   3040   case ARM::VLDMDIA:
   3041   case ARM::VLDMDIA_UPD:
   3042   case ARM::VLDMDDB_UPD:
   3043   case ARM::VLDMSIA:
   3044   case ARM::VLDMSIA_UPD:
   3045   case ARM::VLDMSDB_UPD:
   3046   case ARM::VSTMDIA:
   3047   case ARM::VSTMDIA_UPD:
   3048   case ARM::VSTMDDB_UPD:
   3049   case ARM::VSTMSIA:
   3050   case ARM::VSTMSIA_UPD:
   3051   case ARM::VSTMSDB_UPD: {
   3052     unsigned NumRegs = MI->getNumOperands() - Desc.getNumOperands();
   3053     return (NumRegs / 2) + (NumRegs % 2) + 1;
   3054   }
   3055 
   3056   case ARM::LDMIA_RET:
   3057   case ARM::LDMIA:
   3058   case ARM::LDMDA:
   3059   case ARM::LDMDB:
   3060   case ARM::LDMIB:
   3061   case ARM::LDMIA_UPD:
   3062   case ARM::LDMDA_UPD:
   3063   case ARM::LDMDB_UPD:
   3064   case ARM::LDMIB_UPD:
   3065   case ARM::STMIA:
   3066   case ARM::STMDA:
   3067   case ARM::STMDB:
   3068   case ARM::STMIB:
   3069   case ARM::STMIA_UPD:
   3070   case ARM::STMDA_UPD:
   3071   case ARM::STMDB_UPD:
   3072   case ARM::STMIB_UPD:
   3073   case ARM::tLDMIA:
   3074   case ARM::tLDMIA_UPD:
   3075   case ARM::tSTMIA_UPD:
   3076   case ARM::tPOP_RET:
   3077   case ARM::tPOP:
   3078   case ARM::tPUSH:
   3079   case ARM::t2LDMIA_RET:
   3080   case ARM::t2LDMIA:
   3081   case ARM::t2LDMDB:
   3082   case ARM::t2LDMIA_UPD:
   3083   case ARM::t2LDMDB_UPD:
   3084   case ARM::t2STMIA:
   3085   case ARM::t2STMDB:
   3086   case ARM::t2STMIA_UPD:
   3087   case ARM::t2STMDB_UPD: {
   3088     unsigned NumRegs = MI->getNumOperands() - Desc.getNumOperands() + 1;
   3089     if (Subtarget.isSwift()) {
   3090       int UOps = 1 + NumRegs;  // One for address computation, one for each ld / st.
   3091       switch (Opc) {
   3092       default: break;
   3093       case ARM::VLDMDIA_UPD:
   3094       case ARM::VLDMDDB_UPD:
   3095       case ARM::VLDMSIA_UPD:
   3096       case ARM::VLDMSDB_UPD:
   3097       case ARM::VSTMDIA_UPD:
   3098       case ARM::VSTMDDB_UPD:
   3099       case ARM::VSTMSIA_UPD:
   3100       case ARM::VSTMSDB_UPD:
   3101       case ARM::LDMIA_UPD:
   3102       case ARM::LDMDA_UPD:
   3103       case ARM::LDMDB_UPD:
   3104       case ARM::LDMIB_UPD:
   3105       case ARM::STMIA_UPD:
   3106       case ARM::STMDA_UPD:
   3107       case ARM::STMDB_UPD:
   3108       case ARM::STMIB_UPD:
   3109       case ARM::tLDMIA_UPD:
   3110       case ARM::tSTMIA_UPD:
   3111       case ARM::t2LDMIA_UPD:
   3112       case ARM::t2LDMDB_UPD:
   3113       case ARM::t2STMIA_UPD:
   3114       case ARM::t2STMDB_UPD:
   3115         ++UOps; // One for base register writeback.
   3116         break;
   3117       case ARM::LDMIA_RET:
   3118       case ARM::tPOP_RET:
   3119       case ARM::t2LDMIA_RET:
   3120         UOps += 2; // One for base reg wb, one for write to pc.
   3121         break;
   3122       }
   3123       return UOps;
   3124     } else if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) {
   3125       if (NumRegs < 4)
   3126         return 2;
   3127       // 4 registers would be issued: 2, 2.
   3128       // 5 registers would be issued: 2, 2, 1.
   3129       int A8UOps = (NumRegs / 2);
   3130       if (NumRegs % 2)
   3131         ++A8UOps;
   3132       return A8UOps;
   3133     } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) {
   3134       int A9UOps = (NumRegs / 2);
   3135       // If there are odd number of registers or if it's not 64-bit aligned,
   3136       // then it takes an extra AGU (Address Generation Unit) cycle.
   3137       if ((NumRegs % 2) ||
   3138           !MI->hasOneMemOperand() ||
   3139           (*MI->memoperands_begin())->getAlignment() < 8)
   3140         ++A9UOps;
   3141       return A9UOps;
   3142     } else {
   3143       // Assume the worst.
   3144       return NumRegs;
   3145     }
   3146   }
   3147   }
   3148 }
   3149 
   3150 int
   3151 ARMBaseInstrInfo::getVLDMDefCycle(const InstrItineraryData *ItinData,
   3152                                   const MCInstrDesc &DefMCID,
   3153                                   unsigned DefClass,
   3154                                   unsigned DefIdx, unsigned DefAlign) const {
   3155   int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1;
   3156   if (RegNo <= 0)
   3157     // Def is the address writeback.
   3158     return ItinData->getOperandCycle(DefClass, DefIdx);
   3159 
   3160   int DefCycle;
   3161   if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) {
   3162     // (regno / 2) + (regno % 2) + 1
   3163     DefCycle = RegNo / 2 + 1;
   3164     if (RegNo % 2)
   3165       ++DefCycle;
   3166   } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) {
   3167     DefCycle = RegNo;
   3168     bool isSLoad = false;
   3169 
   3170     switch (DefMCID.getOpcode()) {
   3171     default: break;
   3172     case ARM::VLDMSIA:
   3173     case ARM::VLDMSIA_UPD:
   3174     case ARM::VLDMSDB_UPD:
   3175       isSLoad = true;
   3176       break;
   3177     }
   3178 
   3179     // If there are odd number of 'S' registers or if it's not 64-bit aligned,
   3180     // then it takes an extra cycle.
   3181     if ((isSLoad && (RegNo % 2)) || DefAlign < 8)
   3182       ++DefCycle;
   3183   } else {
   3184     // Assume the worst.
   3185     DefCycle = RegNo + 2;
   3186   }
   3187 
   3188   return DefCycle;
   3189 }
   3190 
   3191 int
   3192 ARMBaseInstrInfo::getLDMDefCycle(const InstrItineraryData *ItinData,
   3193                                  const MCInstrDesc &DefMCID,
   3194                                  unsigned DefClass,
   3195                                  unsigned DefIdx, unsigned DefAlign) const {
   3196   int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1;
   3197   if (RegNo <= 0)
   3198     // Def is the address writeback.
   3199     return ItinData->getOperandCycle(DefClass, DefIdx);
   3200 
   3201   int DefCycle;
   3202   if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) {
   3203     // 4 registers would be issued: 1, 2, 1.
   3204     // 5 registers would be issued: 1, 2, 2.
   3205     DefCycle = RegNo / 2;
   3206     if (DefCycle < 1)
   3207       DefCycle = 1;
   3208     // Result latency is issue cycle + 2: E2.
   3209     DefCycle += 2;
   3210   } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) {
   3211     DefCycle = (RegNo / 2);
   3212     // If there are odd number of registers or if it's not 64-bit aligned,
   3213     // then it takes an extra AGU (Address Generation Unit) cycle.
   3214     if ((RegNo % 2) || DefAlign < 8)
   3215       ++DefCycle;
   3216     // Result latency is AGU cycles + 2.
   3217     DefCycle += 2;
   3218   } else {
   3219     // Assume the worst.
   3220     DefCycle = RegNo + 2;
   3221   }
   3222 
   3223   return DefCycle;
   3224 }
   3225 
   3226 int
   3227 ARMBaseInstrInfo::getVSTMUseCycle(const InstrItineraryData *ItinData,
   3228                                   const MCInstrDesc &UseMCID,
   3229                                   unsigned UseClass,
   3230                                   unsigned UseIdx, unsigned UseAlign) const {
   3231   int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1;
   3232   if (RegNo <= 0)
   3233     return ItinData->getOperandCycle(UseClass, UseIdx);
   3234 
   3235   int UseCycle;
   3236   if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) {
   3237     // (regno / 2) + (regno % 2) + 1
   3238     UseCycle = RegNo / 2 + 1;
   3239     if (RegNo % 2)
   3240       ++UseCycle;
   3241   } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) {
   3242     UseCycle = RegNo;
   3243     bool isSStore = false;
   3244 
   3245     switch (UseMCID.getOpcode()) {
   3246     default: break;
   3247     case ARM::VSTMSIA:
   3248     case ARM::VSTMSIA_UPD:
   3249     case ARM::VSTMSDB_UPD:
   3250       isSStore = true;
   3251       break;
   3252     }
   3253 
   3254     // If there are odd number of 'S' registers or if it's not 64-bit aligned,
   3255     // then it takes an extra cycle.
   3256     if ((isSStore && (RegNo % 2)) || UseAlign < 8)
   3257       ++UseCycle;
   3258   } else {
   3259     // Assume the worst.
   3260     UseCycle = RegNo + 2;
   3261   }
   3262 
   3263   return UseCycle;
   3264 }
   3265 
   3266 int
   3267 ARMBaseInstrInfo::getSTMUseCycle(const InstrItineraryData *ItinData,
   3268                                  const MCInstrDesc &UseMCID,
   3269                                  unsigned UseClass,
   3270                                  unsigned UseIdx, unsigned UseAlign) const {
   3271   int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1;
   3272   if (RegNo <= 0)
   3273     return ItinData->getOperandCycle(UseClass, UseIdx);
   3274 
   3275   int UseCycle;
   3276   if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) {
   3277     UseCycle = RegNo / 2;
   3278     if (UseCycle < 2)
   3279       UseCycle = 2;
   3280     // Read in E3.
   3281     UseCycle += 2;
   3282   } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) {
   3283     UseCycle = (RegNo / 2);
   3284     // If there are odd number of registers or if it's not 64-bit aligned,
   3285     // then it takes an extra AGU (Address Generation Unit) cycle.
   3286     if ((RegNo % 2) || UseAlign < 8)
   3287       ++UseCycle;
   3288   } else {
   3289     // Assume the worst.
   3290     UseCycle = 1;
   3291   }
   3292   return UseCycle;
   3293 }
   3294 
   3295 int
   3296 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData,
   3297                                     const MCInstrDesc &DefMCID,
   3298                                     unsigned DefIdx, unsigned DefAlign,
   3299                                     const MCInstrDesc &UseMCID,
   3300                                     unsigned UseIdx, unsigned UseAlign) const {
   3301   unsigned DefClass = DefMCID.getSchedClass();
   3302   unsigned UseClass = UseMCID.getSchedClass();
   3303 
   3304   if (DefIdx < DefMCID.getNumDefs() && UseIdx < UseMCID.getNumOperands())
   3305     return ItinData->getOperandLatency(DefClass, DefIdx, UseClass, UseIdx);
   3306 
   3307   // This may be a def / use of a variable_ops instruction, the operand
   3308   // latency might be determinable dynamically. Let the target try to
   3309   // figure it out.
   3310   int DefCycle = -1;
   3311   bool LdmBypass = false;
   3312   switch (DefMCID.getOpcode()) {
   3313   default:
   3314     DefCycle = ItinData->getOperandCycle(DefClass, DefIdx);
   3315     break;
   3316 
   3317   case ARM::VLDMDIA:
   3318   case ARM::VLDMDIA_UPD:
   3319   case ARM::VLDMDDB_UPD:
   3320   case ARM::VLDMSIA:
   3321   case ARM::VLDMSIA_UPD:
   3322   case ARM::VLDMSDB_UPD:
   3323     DefCycle = getVLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign);
   3324     break;
   3325 
   3326   case ARM::LDMIA_RET:
   3327   case ARM::LDMIA:
   3328   case ARM::LDMDA:
   3329   case ARM::LDMDB:
   3330   case ARM::LDMIB:
   3331   case ARM::LDMIA_UPD:
   3332   case ARM::LDMDA_UPD:
   3333   case ARM::LDMDB_UPD:
   3334   case ARM::LDMIB_UPD:
   3335   case ARM::tLDMIA:
   3336   case ARM::tLDMIA_UPD:
   3337   case ARM::tPUSH:
   3338   case ARM::t2LDMIA_RET:
   3339   case ARM::t2LDMIA:
   3340   case ARM::t2LDMDB:
   3341   case ARM::t2LDMIA_UPD:
   3342   case ARM::t2LDMDB_UPD:
   3343     LdmBypass = 1;
   3344     DefCycle = getLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign);
   3345     break;
   3346   }
   3347 
   3348   if (DefCycle == -1)
   3349     // We can't seem to determine the result latency of the def, assume it's 2.
   3350     DefCycle = 2;
   3351 
   3352   int UseCycle = -1;
   3353   switch (UseMCID.getOpcode()) {
   3354   default:
   3355     UseCycle = ItinData->getOperandCycle(UseClass, UseIdx);
   3356     break;
   3357 
   3358   case ARM::VSTMDIA:
   3359   case ARM::VSTMDIA_UPD:
   3360   case ARM::VSTMDDB_UPD:
   3361   case ARM::VSTMSIA:
   3362   case ARM::VSTMSIA_UPD:
   3363   case ARM::VSTMSDB_UPD:
   3364     UseCycle = getVSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign);
   3365     break;
   3366 
   3367   case ARM::STMIA:
   3368   case ARM::STMDA:
   3369   case ARM::STMDB:
   3370   case ARM::STMIB:
   3371   case ARM::STMIA_UPD:
   3372   case ARM::STMDA_UPD:
   3373   case ARM::STMDB_UPD:
   3374   case ARM::STMIB_UPD:
   3375   case ARM::tSTMIA_UPD:
   3376   case ARM::tPOP_RET:
   3377   case ARM::tPOP:
   3378   case ARM::t2STMIA:
   3379   case ARM::t2STMDB:
   3380   case ARM::t2STMIA_UPD:
   3381   case ARM::t2STMDB_UPD:
   3382     UseCycle = getSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign);
   3383     break;
   3384   }
   3385 
   3386   if (UseCycle == -1)
   3387     // Assume it's read in the first stage.
   3388     UseCycle = 1;
   3389 
   3390   UseCycle = DefCycle - UseCycle + 1;
   3391   if (UseCycle > 0) {
   3392     if (LdmBypass) {
   3393       // It's a variable_ops instruction so we can't use DefIdx here. Just use
   3394       // first def operand.
   3395       if (ItinData->hasPipelineForwarding(DefClass, DefMCID.getNumOperands()-1,
   3396                                           UseClass, UseIdx))
   3397         --UseCycle;
   3398     } else if (ItinData->hasPipelineForwarding(DefClass, DefIdx,
   3399                                                UseClass, UseIdx)) {
   3400       --UseCycle;
   3401     }
   3402   }
   3403 
   3404   return UseCycle;
   3405 }
   3406 
   3407 static const MachineInstr *getBundledDefMI(const TargetRegisterInfo *TRI,
   3408                                            const MachineInstr *MI, unsigned Reg,
   3409                                            unsigned &DefIdx, unsigned &Dist) {
   3410   Dist = 0;
   3411 
   3412   MachineBasicBlock::const_iterator I = MI; ++I;
   3413   MachineBasicBlock::const_instr_iterator II = std::prev(I.getInstrIterator());
   3414   assert(II->isInsideBundle() && "Empty bundle?");
   3415 
   3416   int Idx = -1;
   3417   while (II->isInsideBundle()) {
   3418     Idx = II->findRegisterDefOperandIdx(Reg, false, true, TRI);
   3419     if (Idx != -1)
   3420       break;
   3421     --II;
   3422     ++Dist;
   3423   }
   3424 
   3425   assert(Idx != -1 && "Cannot find bundled definition!");
   3426   DefIdx = Idx;
   3427   return &*II;
   3428 }
   3429 
   3430 static const MachineInstr *getBundledUseMI(const TargetRegisterInfo *TRI,
   3431                                            const MachineInstr *MI, unsigned Reg,
   3432                                            unsigned &UseIdx, unsigned &Dist) {
   3433   Dist = 0;
   3434 
   3435   MachineBasicBlock::const_instr_iterator II = ++MI->getIterator();
   3436   assert(II->isInsideBundle() && "Empty bundle?");
   3437   MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
   3438 
   3439   // FIXME: This doesn't properly handle multiple uses.
   3440   int Idx = -1;
   3441   while (II != E && II->isInsideBundle()) {
   3442     Idx = II->findRegisterUseOperandIdx(Reg, false, TRI);
   3443     if (Idx != -1)
   3444       break;
   3445     if (II->getOpcode() != ARM::t2IT)
   3446       ++Dist;
   3447     ++II;
   3448   }
   3449 
   3450   if (Idx == -1) {
   3451     Dist = 0;
   3452     return nullptr;
   3453   }
   3454 
   3455   UseIdx = Idx;
   3456   return &*II;
   3457 }
   3458 
   3459 /// Return the number of cycles to add to (or subtract from) the static
   3460 /// itinerary based on the def opcode and alignment. The caller will ensure that
   3461 /// adjusted latency is at least one cycle.
   3462 static int adjustDefLatency(const ARMSubtarget &Subtarget,
   3463                             const MachineInstr *DefMI,
   3464                             const MCInstrDesc *DefMCID, unsigned DefAlign) {
   3465   int Adjust = 0;
   3466   if (Subtarget.isCortexA8() || Subtarget.isLikeA9() || Subtarget.isCortexA7()) {
   3467     // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2]
   3468     // variants are one cycle cheaper.
   3469     switch (DefMCID->getOpcode()) {
   3470     default: break;
   3471     case ARM::LDRrs:
   3472     case ARM::LDRBrs: {
   3473       unsigned ShOpVal = DefMI->getOperand(3).getImm();
   3474       unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
   3475       if (ShImm == 0 ||
   3476           (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))
   3477         --Adjust;
   3478       break;
   3479     }
   3480     case ARM::t2LDRs:
   3481     case ARM::t2LDRBs:
   3482     case ARM::t2LDRHs:
   3483     case ARM::t2LDRSHs: {
   3484       // Thumb2 mode: lsl only.
   3485       unsigned ShAmt = DefMI->getOperand(3).getImm();
   3486       if (ShAmt == 0 || ShAmt == 2)
   3487         --Adjust;
   3488       break;
   3489     }
   3490     }
   3491   } else if (Subtarget.isSwift()) {
   3492     // FIXME: Properly handle all of the latency adjustments for address
   3493     // writeback.
   3494     switch (DefMCID->getOpcode()) {
   3495     default: break;
   3496     case ARM::LDRrs:
   3497     case ARM::LDRBrs: {
   3498       unsigned ShOpVal = DefMI->getOperand(3).getImm();
   3499       bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
   3500       unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
   3501       if (!isSub &&
   3502           (ShImm == 0 ||
   3503            ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
   3504             ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
   3505         Adjust -= 2;
   3506       else if (!isSub &&
   3507                ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr)
   3508         --Adjust;
   3509       break;
   3510     }
   3511     case ARM::t2LDRs:
   3512     case ARM::t2LDRBs:
   3513     case ARM::t2LDRHs:
   3514     case ARM::t2LDRSHs: {
   3515       // Thumb2 mode: lsl only.
   3516       unsigned ShAmt = DefMI->getOperand(3).getImm();
   3517       if (ShAmt == 0 || ShAmt == 1 || ShAmt == 2 || ShAmt == 3)
   3518         Adjust -= 2;
   3519       break;
   3520     }
   3521     }
   3522   }
   3523 
   3524   if (DefAlign < 8 && Subtarget.isLikeA9()) {
   3525     switch (DefMCID->getOpcode()) {
   3526     default: break;
   3527     case ARM::VLD1q8:
   3528     case ARM::VLD1q16:
   3529     case ARM::VLD1q32:
   3530     case ARM::VLD1q64:
   3531     case ARM::VLD1q8wb_fixed:
   3532     case ARM::VLD1q16wb_fixed:
   3533     case ARM::VLD1q32wb_fixed:
   3534     case ARM::VLD1q64wb_fixed:
   3535     case ARM::VLD1q8wb_register:
   3536     case ARM::VLD1q16wb_register:
   3537     case ARM::VLD1q32wb_register:
   3538     case ARM::VLD1q64wb_register:
   3539     case ARM::VLD2d8:
   3540     case ARM::VLD2d16:
   3541     case ARM::VLD2d32:
   3542     case ARM::VLD2q8:
   3543     case ARM::VLD2q16:
   3544     case ARM::VLD2q32:
   3545     case ARM::VLD2d8wb_fixed:
   3546     case ARM::VLD2d16wb_fixed:
   3547     case ARM::VLD2d32wb_fixed:
   3548     case ARM::VLD2q8wb_fixed:
   3549     case ARM::VLD2q16wb_fixed:
   3550     case ARM::VLD2q32wb_fixed:
   3551     case ARM::VLD2d8wb_register:
   3552     case ARM::VLD2d16wb_register:
   3553     case ARM::VLD2d32wb_register:
   3554     case ARM::VLD2q8wb_register:
   3555     case ARM::VLD2q16wb_register:
   3556     case ARM::VLD2q32wb_register:
   3557     case ARM::VLD3d8:
   3558     case ARM::VLD3d16:
   3559     case ARM::VLD3d32:
   3560     case ARM::VLD1d64T:
   3561     case ARM::VLD3d8_UPD:
   3562     case ARM::VLD3d16_UPD:
   3563     case ARM::VLD3d32_UPD:
   3564     case ARM::VLD1d64Twb_fixed:
   3565     case ARM::VLD1d64Twb_register:
   3566     case ARM::VLD3q8_UPD:
   3567     case ARM::VLD3q16_UPD:
   3568     case ARM::VLD3q32_UPD:
   3569     case ARM::VLD4d8:
   3570     case ARM::VLD4d16:
   3571     case ARM::VLD4d32:
   3572     case ARM::VLD1d64Q:
   3573     case ARM::VLD4d8_UPD:
   3574     case ARM::VLD4d16_UPD:
   3575     case ARM::VLD4d32_UPD:
   3576     case ARM::VLD1d64Qwb_fixed:
   3577     case ARM::VLD1d64Qwb_register:
   3578     case ARM::VLD4q8_UPD:
   3579     case ARM::VLD4q16_UPD:
   3580     case ARM::VLD4q32_UPD:
   3581     case ARM::VLD1DUPq8:
   3582     case ARM::VLD1DUPq16:
   3583     case ARM::VLD1DUPq32:
   3584     case ARM::VLD1DUPq8wb_fixed:
   3585     case ARM::VLD1DUPq16wb_fixed:
   3586     case ARM::VLD1DUPq32wb_fixed:
   3587     case ARM::VLD1DUPq8wb_register:
   3588     case ARM::VLD1DUPq16wb_register:
   3589     case ARM::VLD1DUPq32wb_register:
   3590     case ARM::VLD2DUPd8:
   3591     case ARM::VLD2DUPd16:
   3592     case ARM::VLD2DUPd32:
   3593     case ARM::VLD2DUPd8wb_fixed:
   3594     case ARM::VLD2DUPd16wb_fixed:
   3595     case ARM::VLD2DUPd32wb_fixed:
   3596     case ARM::VLD2DUPd8wb_register:
   3597     case ARM::VLD2DUPd16wb_register:
   3598     case ARM::VLD2DUPd32wb_register:
   3599     case ARM::VLD4DUPd8:
   3600     case ARM::VLD4DUPd16:
   3601     case ARM::VLD4DUPd32:
   3602     case ARM::VLD4DUPd8_UPD:
   3603     case ARM::VLD4DUPd16_UPD:
   3604     case ARM::VLD4DUPd32_UPD:
   3605     case ARM::VLD1LNd8:
   3606     case ARM::VLD1LNd16:
   3607     case ARM::VLD1LNd32:
   3608     case ARM::VLD1LNd8_UPD:
   3609     case ARM::VLD1LNd16_UPD:
   3610     case ARM::VLD1LNd32_UPD:
   3611     case ARM::VLD2LNd8:
   3612     case ARM::VLD2LNd16:
   3613     case ARM::VLD2LNd32:
   3614     case ARM::VLD2LNq16:
   3615     case ARM::VLD2LNq32:
   3616     case ARM::VLD2LNd8_UPD:
   3617     case ARM::VLD2LNd16_UPD:
   3618     case ARM::VLD2LNd32_UPD:
   3619     case ARM::VLD2LNq16_UPD:
   3620     case ARM::VLD2LNq32_UPD:
   3621     case ARM::VLD4LNd8:
   3622     case ARM::VLD4LNd16:
   3623     case ARM::VLD4LNd32:
   3624     case ARM::VLD4LNq16:
   3625     case ARM::VLD4LNq32:
   3626     case ARM::VLD4LNd8_UPD:
   3627     case ARM::VLD4LNd16_UPD:
   3628     case ARM::VLD4LNd32_UPD:
   3629     case ARM::VLD4LNq16_UPD:
   3630     case ARM::VLD4LNq32_UPD:
   3631       // If the address is not 64-bit aligned, the latencies of these
   3632       // instructions increases by one.
   3633       ++Adjust;
   3634       break;
   3635     }
   3636   }
   3637   return Adjust;
   3638 }
   3639 
   3640 
   3641 
   3642 int
   3643 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData,
   3644                                     const MachineInstr *DefMI, unsigned DefIdx,
   3645                                     const MachineInstr *UseMI,
   3646                                     unsigned UseIdx) const {
   3647   // No operand latency. The caller may fall back to getInstrLatency.
   3648   if (!ItinData || ItinData->isEmpty())
   3649     return -1;
   3650 
   3651   const MachineOperand &DefMO = DefMI->getOperand(DefIdx);
   3652   unsigned Reg = DefMO.getReg();
   3653   const MCInstrDesc *DefMCID = &DefMI->getDesc();
   3654   const MCInstrDesc *UseMCID = &UseMI->getDesc();
   3655 
   3656   unsigned DefAdj = 0;
   3657   if (DefMI->isBundle()) {
   3658     DefMI = getBundledDefMI(&getRegisterInfo(), DefMI, Reg, DefIdx, DefAdj);
   3659     DefMCID = &DefMI->getDesc();
   3660   }
   3661   if (DefMI->isCopyLike() || DefMI->isInsertSubreg() ||
   3662       DefMI->isRegSequence() || DefMI->isImplicitDef()) {
   3663     return 1;
   3664   }
   3665 
   3666   unsigned UseAdj = 0;
   3667   if (UseMI->isBundle()) {
   3668     unsigned NewUseIdx;
   3669     const MachineInstr *NewUseMI = getBundledUseMI(&getRegisterInfo(), UseMI,
   3670                                                    Reg, NewUseIdx, UseAdj);
   3671     if (!NewUseMI)
   3672       return -1;
   3673 
   3674     UseMI = NewUseMI;
   3675     UseIdx = NewUseIdx;
   3676     UseMCID = &UseMI->getDesc();
   3677   }
   3678 
   3679   if (Reg == ARM::CPSR) {
   3680     if (DefMI->getOpcode() == ARM::FMSTAT) {
   3681       // fpscr -> cpsr stalls over 20 cycles on A8 (and earlier?)
   3682       return Subtarget.isLikeA9() ? 1 : 20;
   3683     }
   3684 
   3685     // CPSR set and branch can be paired in the same cycle.
   3686     if (UseMI->isBranch())
   3687       return 0;
   3688 
   3689     // Otherwise it takes the instruction latency (generally one).
   3690     unsigned Latency = getInstrLatency(ItinData, DefMI);
   3691 
   3692     // For Thumb2 and -Os, prefer scheduling CPSR setting instruction close to
   3693     // its uses. Instructions which are otherwise scheduled between them may
   3694     // incur a code size penalty (not able to use the CPSR setting 16-bit
   3695     // instructions).
   3696     if (Latency > 0 && Subtarget.isThumb2()) {
   3697       const MachineFunction *MF = DefMI->getParent()->getParent();
   3698       // FIXME: Use Function::optForSize().
   3699       if (MF->getFunction()->hasFnAttribute(Attribute::OptimizeForSize))
   3700         --Latency;
   3701     }
   3702     return Latency;
   3703   }
   3704 
   3705   if (DefMO.isImplicit() || UseMI->getOperand(UseIdx).isImplicit())
   3706     return -1;
   3707 
   3708   unsigned DefAlign = DefMI->hasOneMemOperand()
   3709     ? (*DefMI->memoperands_begin())->getAlignment() : 0;
   3710   unsigned UseAlign = UseMI->hasOneMemOperand()
   3711     ? (*UseMI->memoperands_begin())->getAlignment() : 0;
   3712 
   3713   // Get the itinerary's latency if possible, and handle variable_ops.
   3714   int Latency = getOperandLatency(ItinData, *DefMCID, DefIdx, DefAlign,
   3715                                   *UseMCID, UseIdx, UseAlign);
   3716   // Unable to find operand latency. The caller may resort to getInstrLatency.
   3717   if (Latency < 0)
   3718     return Latency;
   3719 
   3720   // Adjust for IT block position.
   3721   int Adj = DefAdj + UseAdj;
   3722 
   3723   // Adjust for dynamic def-side opcode variants not captured by the itinerary.
   3724   Adj += adjustDefLatency(Subtarget, DefMI, DefMCID, DefAlign);
   3725   if (Adj >= 0 || (int)Latency > -Adj) {
   3726     return Latency + Adj;
   3727   }
   3728   // Return the itinerary latency, which may be zero but not less than zero.
   3729   return Latency;
   3730 }
   3731 
   3732 int
   3733 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData,
   3734                                     SDNode *DefNode, unsigned DefIdx,
   3735                                     SDNode *UseNode, unsigned UseIdx) const {
   3736   if (!DefNode->isMachineOpcode())
   3737     return 1;
   3738 
   3739   const MCInstrDesc &DefMCID = get(DefNode->getMachineOpcode());
   3740 
   3741   if (isZeroCost(DefMCID.Opcode))
   3742     return 0;
   3743 
   3744   if (!ItinData || ItinData->isEmpty())
   3745     return DefMCID.mayLoad() ? 3 : 1;
   3746 
   3747   if (!UseNode->isMachineOpcode()) {
   3748     int Latency = ItinData->getOperandCycle(DefMCID.getSchedClass(), DefIdx);
   3749     if (Subtarget.isLikeA9() || Subtarget.isSwift())
   3750       return Latency <= 2 ? 1 : Latency - 1;
   3751     else
   3752       return Latency <= 3 ? 1 : Latency - 2;
   3753   }
   3754 
   3755   const MCInstrDesc &UseMCID = get(UseNode->getMachineOpcode());
   3756   const MachineSDNode *DefMN = dyn_cast<MachineSDNode>(DefNode);
   3757   unsigned DefAlign = !DefMN->memoperands_empty()
   3758     ? (*DefMN->memoperands_begin())->getAlignment() : 0;
   3759   const MachineSDNode *UseMN = dyn_cast<MachineSDNode>(UseNode);
   3760   unsigned UseAlign = !UseMN->memoperands_empty()
   3761     ? (*UseMN->memoperands_begin())->getAlignment() : 0;
   3762   int Latency = getOperandLatency(ItinData, DefMCID, DefIdx, DefAlign,
   3763                                   UseMCID, UseIdx, UseAlign);
   3764 
   3765   if (Latency > 1 &&
   3766       (Subtarget.isCortexA8() || Subtarget.isLikeA9() ||
   3767        Subtarget.isCortexA7())) {
   3768     // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2]
   3769     // variants are one cycle cheaper.
   3770     switch (DefMCID.getOpcode()) {
   3771     default: break;
   3772     case ARM::LDRrs:
   3773     case ARM::LDRBrs: {
   3774       unsigned ShOpVal =
   3775         cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue();
   3776       unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
   3777       if (ShImm == 0 ||
   3778           (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))
   3779         --Latency;
   3780       break;
   3781     }
   3782     case ARM::t2LDRs:
   3783     case ARM::t2LDRBs:
   3784     case ARM::t2LDRHs:
   3785     case ARM::t2LDRSHs: {
   3786       // Thumb2 mode: lsl only.
   3787       unsigned ShAmt =
   3788         cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue();
   3789       if (ShAmt == 0 || ShAmt == 2)
   3790         --Latency;
   3791       break;
   3792     }
   3793     }
   3794   } else if (DefIdx == 0 && Latency > 2 && Subtarget.isSwift()) {
   3795     // FIXME: Properly handle all of the latency adjustments for address
   3796     // writeback.
   3797     switch (DefMCID.getOpcode()) {
   3798     default: break;
   3799     case ARM::LDRrs:
   3800     case ARM::LDRBrs: {
   3801       unsigned ShOpVal =
   3802         cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue();
   3803       unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
   3804       if (ShImm == 0 ||
   3805           ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
   3806            ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))
   3807         Latency -= 2;
   3808       else if (ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr)
   3809         --Latency;
   3810       break;
   3811     }
   3812     case ARM::t2LDRs:
   3813     case ARM::t2LDRBs:
   3814     case ARM::t2LDRHs:
   3815     case ARM::t2LDRSHs: {
   3816       // Thumb2 mode: lsl 0-3 only.
   3817       Latency -= 2;
   3818       break;
   3819     }
   3820     }
   3821   }
   3822 
   3823   if (DefAlign < 8 && Subtarget.isLikeA9())
   3824     switch (DefMCID.getOpcode()) {
   3825     default: break;
   3826     case ARM::VLD1q8:
   3827     case ARM::VLD1q16:
   3828     case ARM::VLD1q32:
   3829     case ARM::VLD1q64:
   3830     case ARM::VLD1q8wb_register:
   3831     case ARM::VLD1q16wb_register:
   3832     case ARM::VLD1q32wb_register:
   3833     case ARM::VLD1q64wb_register:
   3834     case ARM::VLD1q8wb_fixed:
   3835     case ARM::VLD1q16wb_fixed:
   3836     case ARM::VLD1q32wb_fixed:
   3837     case ARM::VLD1q64wb_fixed:
   3838     case ARM::VLD2d8:
   3839     case ARM::VLD2d16:
   3840     case ARM::VLD2d32:
   3841     case ARM::VLD2q8Pseudo:
   3842     case ARM::VLD2q16Pseudo:
   3843     case ARM::VLD2q32Pseudo:
   3844     case ARM::VLD2d8wb_fixed:
   3845     case ARM::VLD2d16wb_fixed:
   3846     case ARM::VLD2d32wb_fixed:
   3847     case ARM::VLD2q8PseudoWB_fixed:
   3848     case ARM::VLD2q16PseudoWB_fixed:
   3849     case ARM::VLD2q32PseudoWB_fixed:
   3850     case ARM::VLD2d8wb_register:
   3851     case ARM::VLD2d16wb_register:
   3852     case ARM::VLD2d32wb_register:
   3853     case ARM::VLD2q8PseudoWB_register:
   3854     case ARM::VLD2q16PseudoWB_register:
   3855     case ARM::VLD2q32PseudoWB_register:
   3856     case ARM::VLD3d8Pseudo:
   3857     case ARM::VLD3d16Pseudo:
   3858     case ARM::VLD3d32Pseudo:
   3859     case ARM::VLD1d64TPseudo:
   3860     case ARM::VLD1d64TPseudoWB_fixed:
   3861     case ARM::VLD3d8Pseudo_UPD:
   3862     case ARM::VLD3d16Pseudo_UPD:
   3863     case ARM::VLD3d32Pseudo_UPD:
   3864     case ARM::VLD3q8Pseudo_UPD:
   3865     case ARM::VLD3q16Pseudo_UPD:
   3866     case ARM::VLD3q32Pseudo_UPD:
   3867     case ARM::VLD3q8oddPseudo:
   3868     case ARM::VLD3q16oddPseudo:
   3869     case ARM::VLD3q32oddPseudo:
   3870     case ARM::VLD3q8oddPseudo_UPD:
   3871     case ARM::VLD3q16oddPseudo_UPD:
   3872     case ARM::VLD3q32oddPseudo_UPD:
   3873     case ARM::VLD4d8Pseudo:
   3874     case ARM::VLD4d16Pseudo:
   3875     case ARM::VLD4d32Pseudo:
   3876     case ARM::VLD1d64QPseudo:
   3877     case ARM::VLD1d64QPseudoWB_fixed:
   3878     case ARM::VLD4d8Pseudo_UPD:
   3879     case ARM::VLD4d16Pseudo_UPD:
   3880     case ARM::VLD4d32Pseudo_UPD:
   3881     case ARM::VLD4q8Pseudo_UPD:
   3882     case ARM::VLD4q16Pseudo_UPD:
   3883     case ARM::VLD4q32Pseudo_UPD:
   3884     case ARM::VLD4q8oddPseudo:
   3885     case ARM::VLD4q16oddPseudo:
   3886     case ARM::VLD4q32oddPseudo:
   3887     case ARM::VLD4q8oddPseudo_UPD:
   3888     case ARM::VLD4q16oddPseudo_UPD:
   3889     case ARM::VLD4q32oddPseudo_UPD:
   3890     case ARM::VLD1DUPq8:
   3891     case ARM::VLD1DUPq16:
   3892     case ARM::VLD1DUPq32:
   3893     case ARM::VLD1DUPq8wb_fixed:
   3894     case ARM::VLD1DUPq16wb_fixed:
   3895     case ARM::VLD1DUPq32wb_fixed:
   3896     case ARM::VLD1DUPq8wb_register:
   3897     case ARM::VLD1DUPq16wb_register:
   3898     case ARM::VLD1DUPq32wb_register:
   3899     case ARM::VLD2DUPd8:
   3900     case ARM::VLD2DUPd16:
   3901     case ARM::VLD2DUPd32:
   3902     case ARM::VLD2DUPd8wb_fixed:
   3903     case ARM::VLD2DUPd16wb_fixed:
   3904     case ARM::VLD2DUPd32wb_fixed:
   3905     case ARM::VLD2DUPd8wb_register:
   3906     case ARM::VLD2DUPd16wb_register:
   3907     case ARM::VLD2DUPd32wb_register:
   3908     case ARM::VLD4DUPd8Pseudo:
   3909     case ARM::VLD4DUPd16Pseudo:
   3910     case ARM::VLD4DUPd32Pseudo:
   3911     case ARM::VLD4DUPd8Pseudo_UPD:
   3912     case ARM::VLD4DUPd16Pseudo_UPD:
   3913     case ARM::VLD4DUPd32Pseudo_UPD:
   3914     case ARM::VLD1LNq8Pseudo:
   3915     case ARM::VLD1LNq16Pseudo:
   3916     case ARM::VLD1LNq32Pseudo:
   3917     case ARM::VLD1LNq8Pseudo_UPD:
   3918     case ARM::VLD1LNq16Pseudo_UPD:
   3919     case ARM::VLD1LNq32Pseudo_UPD:
   3920     case ARM::VLD2LNd8Pseudo:
   3921     case ARM::VLD2LNd16Pseudo:
   3922     case ARM::VLD2LNd32Pseudo:
   3923     case ARM::VLD2LNq16Pseudo:
   3924     case ARM::VLD2LNq32Pseudo:
   3925     case ARM::VLD2LNd8Pseudo_UPD:
   3926     case ARM::VLD2LNd16Pseudo_UPD:
   3927     case ARM::VLD2LNd32Pseudo_UPD:
   3928     case ARM::VLD2LNq16Pseudo_UPD:
   3929     case ARM::VLD2LNq32Pseudo_UPD:
   3930     case ARM::VLD4LNd8Pseudo:
   3931     case ARM::VLD4LNd16Pseudo:
   3932     case ARM::VLD4LNd32Pseudo:
   3933     case ARM::VLD4LNq16Pseudo:
   3934     case ARM::VLD4LNq32Pseudo:
   3935     case ARM::VLD4LNd8Pseudo_UPD:
   3936     case ARM::VLD4LNd16Pseudo_UPD:
   3937     case ARM::VLD4LNd32Pseudo_UPD:
   3938     case ARM::VLD4LNq16Pseudo_UPD:
   3939     case ARM::VLD4LNq32Pseudo_UPD:
   3940       // If the address is not 64-bit aligned, the latencies of these
   3941       // instructions increases by one.
   3942       ++Latency;
   3943       break;
   3944     }
   3945 
   3946   return Latency;
   3947 }
   3948 
   3949 unsigned ARMBaseInstrInfo::getPredicationCost(const MachineInstr *MI) const {
   3950    if (MI->isCopyLike() || MI->isInsertSubreg() ||
   3951       MI->isRegSequence() || MI->isImplicitDef())
   3952     return 0;
   3953 
   3954   if (MI->isBundle())
   3955     return 0;
   3956 
   3957   const MCInstrDesc &MCID = MI->getDesc();
   3958 
   3959   if (MCID.isCall() || MCID.hasImplicitDefOfPhysReg(ARM::CPSR)) {
   3960     // When predicated, CPSR is an additional source operand for CPSR updating
   3961     // instructions, this apparently increases their latencies.
   3962     return 1;
   3963   }
   3964   return 0;
   3965 }
   3966 
   3967 unsigned ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData,
   3968                                            const MachineInstr *MI,
   3969                                            unsigned *PredCost) const {
   3970   if (MI->isCopyLike() || MI->isInsertSubreg() ||
   3971       MI->isRegSequence() || MI->isImplicitDef())
   3972     return 1;
   3973 
   3974   // An instruction scheduler typically runs on unbundled instructions, however
   3975   // other passes may query the latency of a bundled instruction.
   3976   if (MI->isBundle()) {
   3977     unsigned Latency = 0;
   3978     MachineBasicBlock::const_instr_iterator I = MI->getIterator();
   3979     MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
   3980     while (++I != E && I->isInsideBundle()) {
   3981       if (I->getOpcode() != ARM::t2IT)
   3982         Latency += getInstrLatency(ItinData, &*I, PredCost);
   3983     }
   3984     return Latency;
   3985   }
   3986 
   3987   const MCInstrDesc &MCID = MI->getDesc();
   3988   if (PredCost && (MCID.isCall() || MCID.hasImplicitDefOfPhysReg(ARM::CPSR))) {
   3989     // When predicated, CPSR is an additional source operand for CPSR updating
   3990     // instructions, this apparently increases their latencies.
   3991     *PredCost = 1;
   3992   }
   3993   // Be sure to call getStageLatency for an empty itinerary in case it has a
   3994   // valid MinLatency property.
   3995   if (!ItinData)
   3996     return MI->mayLoad() ? 3 : 1;
   3997 
   3998   unsigned Class = MCID.getSchedClass();
   3999 
   4000   // For instructions with variable uops, use uops as latency.
   4001   if (!ItinData->isEmpty() && ItinData->getNumMicroOps(Class) < 0)
   4002     return getNumMicroOps(ItinData, MI);
   4003 
   4004   // For the common case, fall back on the itinerary's latency.
   4005   unsigned Latency = ItinData->getStageLatency(Class);
   4006 
   4007   // Adjust for dynamic def-side opcode variants not captured by the itinerary.
   4008   unsigned DefAlign = MI->hasOneMemOperand()
   4009     ? (*MI->memoperands_begin())->getAlignment() : 0;
   4010   int Adj = adjustDefLatency(Subtarget, MI, &MCID, DefAlign);
   4011   if (Adj >= 0 || (int)Latency > -Adj) {
   4012     return Latency + Adj;
   4013   }
   4014   return Latency;
   4015 }
   4016 
   4017 int ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData,
   4018                                       SDNode *Node) const {
   4019   if (!Node->isMachineOpcode())
   4020     return 1;
   4021 
   4022   if (!ItinData || ItinData->isEmpty())
   4023     return 1;
   4024 
   4025   unsigned Opcode = Node->getMachineOpcode();
   4026   switch (Opcode) {
   4027   default:
   4028     return ItinData->getStageLatency(get(Opcode).getSchedClass());
   4029   case ARM::VLDMQIA:
   4030   case ARM::VSTMQIA:
   4031     return 2;
   4032   }
   4033 }
   4034 
   4035 bool ARMBaseInstrInfo::
   4036 hasHighOperandLatency(const TargetSchedModel &SchedModel,
   4037                       const MachineRegisterInfo *MRI,
   4038                       const MachineInstr *DefMI, unsigned DefIdx,
   4039                       const MachineInstr *UseMI, unsigned UseIdx) const {
   4040   unsigned DDomain = DefMI->getDesc().TSFlags & ARMII::DomainMask;
   4041   unsigned UDomain = UseMI->getDesc().TSFlags & ARMII::DomainMask;
   4042   if (Subtarget.isCortexA8() &&
   4043       (DDomain == ARMII::DomainVFP || UDomain == ARMII::DomainVFP))
   4044     // CortexA8 VFP instructions are not pipelined.
   4045     return true;
   4046 
   4047   // Hoist VFP / NEON instructions with 4 or higher latency.
   4048   unsigned Latency
   4049     = SchedModel.computeOperandLatency(DefMI, DefIdx, UseMI, UseIdx);
   4050   if (Latency <= 3)
   4051     return false;
   4052   return DDomain == ARMII::DomainVFP || DDomain == ARMII::DomainNEON ||
   4053          UDomain == ARMII::DomainVFP || UDomain == ARMII::DomainNEON;
   4054 }
   4055 
   4056 bool ARMBaseInstrInfo::
   4057 hasLowDefLatency(const TargetSchedModel &SchedModel,
   4058                  const MachineInstr *DefMI, unsigned DefIdx) const {
   4059   const InstrItineraryData *ItinData = SchedModel.getInstrItineraries();
   4060   if (!ItinData || ItinData->isEmpty())
   4061     return false;
   4062 
   4063   unsigned DDomain = DefMI->getDesc().TSFlags & ARMII::DomainMask;
   4064   if (DDomain == ARMII::DomainGeneral) {
   4065     unsigned DefClass = DefMI->getDesc().getSchedClass();
   4066     int DefCycle = ItinData->getOperandCycle(DefClass, DefIdx);
   4067     return (DefCycle != -1 && DefCycle <= 2);
   4068   }
   4069   return false;
   4070 }
   4071 
   4072 bool ARMBaseInstrInfo::verifyInstruction(const MachineInstr *MI,
   4073                                          StringRef &ErrInfo) const {
   4074   if (convertAddSubFlagsOpcode(MI->getOpcode())) {
   4075     ErrInfo = "Pseudo flag setting opcodes only exist in Selection DAG";
   4076     return false;
   4077   }
   4078   return true;
   4079 }
   4080 
   4081 // LoadStackGuard has so far only been implemented for MachO. Different code
   4082 // sequence is needed for other targets.
   4083 void ARMBaseInstrInfo::expandLoadStackGuardBase(MachineBasicBlock::iterator MI,
   4084                                                 unsigned LoadImmOpc,
   4085                                                 unsigned LoadOpc,
   4086                                                 Reloc::Model RM) const {
   4087   MachineBasicBlock &MBB = *MI->getParent();
   4088   DebugLoc DL = MI->getDebugLoc();
   4089   unsigned Reg = MI->getOperand(0).getReg();
   4090   const GlobalValue *GV =
   4091       cast<GlobalValue>((*MI->memoperands_begin())->getValue());
   4092   MachineInstrBuilder MIB;
   4093 
   4094   BuildMI(MBB, MI, DL, get(LoadImmOpc), Reg)
   4095       .addGlobalAddress(GV, 0, ARMII::MO_NONLAZY);
   4096 
   4097   if (Subtarget.GVIsIndirectSymbol(GV, RM)) {
   4098     MIB = BuildMI(MBB, MI, DL, get(LoadOpc), Reg);
   4099     MIB.addReg(Reg, RegState::Kill).addImm(0);
   4100     unsigned Flag = MachineMemOperand::MOLoad | MachineMemOperand::MOInvariant;
   4101     MachineMemOperand *MMO = MBB.getParent()->getMachineMemOperand(
   4102         MachinePointerInfo::getGOT(*MBB.getParent()), Flag, 4, 4);
   4103     MIB.addMemOperand(MMO);
   4104     AddDefaultPred(MIB);
   4105   }
   4106 
   4107   MIB = BuildMI(MBB, MI, DL, get(LoadOpc), Reg);
   4108   MIB.addReg(Reg, RegState::Kill).addImm(0);
   4109   MIB.setMemRefs(MI->memoperands_begin(), MI->memoperands_end());
   4110   AddDefaultPred(MIB);
   4111 }
   4112 
   4113 bool
   4114 ARMBaseInstrInfo::isFpMLxInstruction(unsigned Opcode, unsigned &MulOpc,
   4115                                      unsigned &AddSubOpc,
   4116                                      bool &NegAcc, bool &HasLane) const {
   4117   DenseMap<unsigned, unsigned>::const_iterator I = MLxEntryMap.find(Opcode);
   4118   if (I == MLxEntryMap.end())
   4119     return false;
   4120 
   4121   const ARM_MLxEntry &Entry = ARM_MLxTable[I->second];
   4122   MulOpc = Entry.MulOpc;
   4123   AddSubOpc = Entry.AddSubOpc;
   4124   NegAcc = Entry.NegAcc;
   4125   HasLane = Entry.HasLane;
   4126   return true;
   4127 }
   4128 
   4129 //===----------------------------------------------------------------------===//
   4130 // Execution domains.
   4131 //===----------------------------------------------------------------------===//
   4132 //
   4133 // Some instructions go down the NEON pipeline, some go down the VFP pipeline,
   4134 // and some can go down both.  The vmov instructions go down the VFP pipeline,
   4135 // but they can be changed to vorr equivalents that are executed by the NEON
   4136 // pipeline.
   4137 //
   4138 // We use the following execution domain numbering:
   4139 //
   4140 enum ARMExeDomain {
   4141   ExeGeneric = 0,
   4142   ExeVFP = 1,
   4143   ExeNEON = 2
   4144 };
   4145 //
   4146 // Also see ARMInstrFormats.td and Domain* enums in ARMBaseInfo.h
   4147 //
   4148 std::pair<uint16_t, uint16_t>
   4149 ARMBaseInstrInfo::getExecutionDomain(const MachineInstr *MI) const {
   4150   // If we don't have access to NEON instructions then we won't be able
   4151   // to swizzle anything to the NEON domain. Check to make sure.
   4152   if (Subtarget.hasNEON()) {
   4153     // VMOVD, VMOVRS and VMOVSR are VFP instructions, but can be changed to NEON
   4154     // if they are not predicated.
   4155     if (MI->getOpcode() == ARM::VMOVD && !isPredicated(MI))
   4156       return std::make_pair(ExeVFP, (1 << ExeVFP) | (1 << ExeNEON));
   4157 
   4158     // CortexA9 is particularly picky about mixing the two and wants these
   4159     // converted.
   4160     if (Subtarget.isCortexA9() && !isPredicated(MI) &&
   4161         (MI->getOpcode() == ARM::VMOVRS || MI->getOpcode() == ARM::VMOVSR ||
   4162          MI->getOpcode() == ARM::VMOVS))
   4163       return std::make_pair(ExeVFP, (1 << ExeVFP) | (1 << ExeNEON));
   4164   }
   4165   // No other instructions can be swizzled, so just determine their domain.
   4166   unsigned Domain = MI->getDesc().TSFlags & ARMII::DomainMask;
   4167 
   4168   if (Domain & ARMII::DomainNEON)
   4169     return std::make_pair(ExeNEON, 0);
   4170 
   4171   // Certain instructions can go either way on Cortex-A8.
   4172   // Treat them as NEON instructions.
   4173   if ((Domain & ARMII::DomainNEONA8) && Subtarget.isCortexA8())
   4174     return std::make_pair(ExeNEON, 0);
   4175 
   4176   if (Domain & ARMII::DomainVFP)
   4177     return std::make_pair(ExeVFP, 0);
   4178 
   4179   return std::make_pair(ExeGeneric, 0);
   4180 }
   4181 
   4182 static unsigned getCorrespondingDRegAndLane(const TargetRegisterInfo *TRI,
   4183                                             unsigned SReg, unsigned &Lane) {
   4184   unsigned DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_0, &ARM::DPRRegClass);
   4185   Lane = 0;
   4186 
   4187   if (DReg != ARM::NoRegister)
   4188    return DReg;
   4189 
   4190   Lane = 1;
   4191   DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_1, &ARM::DPRRegClass);
   4192 
   4193   assert(DReg && "S-register with no D super-register?");
   4194   return DReg;
   4195 }
   4196 
   4197 /// getImplicitSPRUseForDPRUse - Given a use of a DPR register and lane,
   4198 /// set ImplicitSReg to a register number that must be marked as implicit-use or
   4199 /// zero if no register needs to be defined as implicit-use.
   4200 ///
   4201 /// If the function cannot determine if an SPR should be marked implicit use or
   4202 /// not, it returns false.
   4203 ///
   4204 /// This function handles cases where an instruction is being modified from taking
   4205 /// an SPR to a DPR[Lane]. A use of the DPR is being added, which may conflict
   4206 /// with an earlier def of an SPR corresponding to DPR[Lane^1] (i.e. the other
   4207 /// lane of the DPR).
   4208 ///
   4209 /// If the other SPR is defined, an implicit-use of it should be added. Else,
   4210 /// (including the case where the DPR itself is defined), it should not.
   4211 ///
   4212 static bool getImplicitSPRUseForDPRUse(const TargetRegisterInfo *TRI,
   4213                                        MachineInstr *MI,
   4214                                        unsigned DReg, unsigned Lane,
   4215                                        unsigned &ImplicitSReg) {
   4216   // If the DPR is defined or used already, the other SPR lane will be chained
   4217   // correctly, so there is nothing to be done.
   4218   if (MI->definesRegister(DReg, TRI) || MI->readsRegister(DReg, TRI)) {
   4219     ImplicitSReg = 0;
   4220     return true;
   4221   }
   4222 
   4223   // Otherwise we need to go searching to see if the SPR is set explicitly.
   4224   ImplicitSReg = TRI->getSubReg(DReg,
   4225                                 (Lane & 1) ? ARM::ssub_0 : ARM::ssub_1);
   4226   MachineBasicBlock::LivenessQueryResult LQR =
   4227     MI->getParent()->computeRegisterLiveness(TRI, ImplicitSReg, MI);
   4228 
   4229   if (LQR == MachineBasicBlock::LQR_Live)
   4230     return true;
   4231   else if (LQR == MachineBasicBlock::LQR_Unknown)
   4232     return false;
   4233 
   4234   // If the register is known not to be live, there is no need to add an
   4235   // implicit-use.
   4236   ImplicitSReg = 0;
   4237   return true;
   4238 }
   4239 
   4240 void
   4241 ARMBaseInstrInfo::setExecutionDomain(MachineInstr *MI, unsigned Domain) const {
   4242   unsigned DstReg, SrcReg, DReg;
   4243   unsigned Lane;
   4244   MachineInstrBuilder MIB(*MI->getParent()->getParent(), MI);
   4245   const TargetRegisterInfo *TRI = &getRegisterInfo();
   4246   switch (MI->getOpcode()) {
   4247     default:
   4248       llvm_unreachable("cannot handle opcode!");
   4249       break;
   4250     case ARM::VMOVD:
   4251       if (Domain != ExeNEON)
   4252         break;
   4253 
   4254       // Zap the predicate operands.
   4255       assert(!isPredicated(MI) && "Cannot predicate a VORRd");
   4256 
   4257       // Make sure we've got NEON instructions.
   4258       assert(Subtarget.hasNEON() && "VORRd requires NEON");
   4259 
   4260       // Source instruction is %DDst = VMOVD %DSrc, 14, %noreg (; implicits)
   4261       DstReg = MI->getOperand(0).getReg();
   4262       SrcReg = MI->getOperand(1).getReg();
   4263 
   4264       for (unsigned i = MI->getDesc().getNumOperands(); i; --i)
   4265         MI->RemoveOperand(i-1);
   4266 
   4267       // Change to a %DDst = VORRd %DSrc, %DSrc, 14, %noreg (; implicits)
   4268       MI->setDesc(get(ARM::VORRd));
   4269       AddDefaultPred(MIB.addReg(DstReg, RegState::Define)
   4270                         .addReg(SrcReg)
   4271                         .addReg(SrcReg));
   4272       break;
   4273     case ARM::VMOVRS:
   4274       if (Domain != ExeNEON)
   4275         break;
   4276       assert(!isPredicated(MI) && "Cannot predicate a VGETLN");
   4277 
   4278       // Source instruction is %RDst = VMOVRS %SSrc, 14, %noreg (; implicits)
   4279       DstReg = MI->getOperand(0).getReg();
   4280       SrcReg = MI->getOperand(1).getReg();
   4281 
   4282       for (unsigned i = MI->getDesc().getNumOperands(); i; --i)
   4283         MI->RemoveOperand(i-1);
   4284 
   4285       DReg = getCorrespondingDRegAndLane(TRI, SrcReg, Lane);
   4286 
   4287       // Convert to %RDst = VGETLNi32 %DSrc, Lane, 14, %noreg (; imps)
   4288       // Note that DSrc has been widened and the other lane may be undef, which
   4289       // contaminates the entire register.
   4290       MI->setDesc(get(ARM::VGETLNi32));
   4291       AddDefaultPred(MIB.addReg(DstReg, RegState::Define)
   4292                         .addReg(DReg, RegState::Undef)
   4293                         .addImm(Lane));
   4294 
   4295       // The old source should be an implicit use, otherwise we might think it
   4296       // was dead before here.
   4297       MIB.addReg(SrcReg, RegState::Implicit);
   4298       break;
   4299     case ARM::VMOVSR: {
   4300       if (Domain != ExeNEON)
   4301         break;
   4302       assert(!isPredicated(MI) && "Cannot predicate a VSETLN");
   4303 
   4304       // Source instruction is %SDst = VMOVSR %RSrc, 14, %noreg (; implicits)
   4305       DstReg = MI->getOperand(0).getReg();
   4306       SrcReg = MI->getOperand(1).getReg();
   4307 
   4308       DReg = getCorrespondingDRegAndLane(TRI, DstReg, Lane);
   4309 
   4310       unsigned ImplicitSReg;
   4311       if (!getImplicitSPRUseForDPRUse(TRI, MI, DReg, Lane, ImplicitSReg))
   4312         break;
   4313 
   4314       for (unsigned i = MI->getDesc().getNumOperands(); i; --i)
   4315         MI->RemoveOperand(i-1);
   4316 
   4317       // Convert to %DDst = VSETLNi32 %DDst, %RSrc, Lane, 14, %noreg (; imps)
   4318       // Again DDst may be undefined at the beginning of this instruction.
   4319       MI->setDesc(get(ARM::VSETLNi32));
   4320       MIB.addReg(DReg, RegState::Define)
   4321          .addReg(DReg, getUndefRegState(!MI->readsRegister(DReg, TRI)))
   4322          .addReg(SrcReg)
   4323          .addImm(Lane);
   4324       AddDefaultPred(MIB);
   4325 
   4326       // The narrower destination must be marked as set to keep previous chains
   4327       // in place.
   4328       MIB.addReg(DstReg, RegState::Define | RegState::Implicit);
   4329       if (ImplicitSReg != 0)
   4330         MIB.addReg(ImplicitSReg, RegState::Implicit);
   4331       break;
   4332     }
   4333     case ARM::VMOVS: {
   4334       if (Domain != ExeNEON)
   4335         break;
   4336 
   4337       // Source instruction is %SDst = VMOVS %SSrc, 14, %noreg (; implicits)
   4338       DstReg = MI->getOperand(0).getReg();
   4339       SrcReg = MI->getOperand(1).getReg();
   4340 
   4341       unsigned DstLane = 0, SrcLane = 0, DDst, DSrc;
   4342       DDst = getCorrespondingDRegAndLane(TRI, DstReg, DstLane);
   4343       DSrc = getCorrespondingDRegAndLane(TRI, SrcReg, SrcLane);
   4344 
   4345       unsigned ImplicitSReg;
   4346       if (!getImplicitSPRUseForDPRUse(TRI, MI, DSrc, SrcLane, ImplicitSReg))
   4347         break;
   4348 
   4349       for (unsigned i = MI->getDesc().getNumOperands(); i; --i)
   4350         MI->RemoveOperand(i-1);
   4351 
   4352       if (DSrc == DDst) {
   4353         // Destination can be:
   4354         //     %DDst = VDUPLN32d %DDst, Lane, 14, %noreg (; implicits)
   4355         MI->setDesc(get(ARM::VDUPLN32d));
   4356         MIB.addReg(DDst, RegState::Define)
   4357            .addReg(DDst, getUndefRegState(!MI->readsRegister(DDst, TRI)))
   4358            .addImm(SrcLane);
   4359         AddDefaultPred(MIB);
   4360 
   4361         // Neither the source or the destination are naturally represented any
   4362         // more, so add them in manually.
   4363         MIB.addReg(DstReg, RegState::Implicit | RegState::Define);
   4364         MIB.addReg(SrcReg, RegState::Implicit);
   4365         if (ImplicitSReg != 0)
   4366           MIB.addReg(ImplicitSReg, RegState::Implicit);
   4367         break;
   4368       }
   4369 
   4370       // In general there's no single instruction that can perform an S <-> S
   4371       // move in NEON space, but a pair of VEXT instructions *can* do the
   4372       // job. It turns out that the VEXTs needed will only use DSrc once, with
   4373       // the position based purely on the combination of lane-0 and lane-1
   4374       // involved. For example
   4375       //     vmov s0, s2 -> vext.32 d0, d0, d1, #1  vext.32 d0, d0, d0, #1
   4376       //     vmov s1, s3 -> vext.32 d0, d1, d0, #1  vext.32 d0, d0, d0, #1
   4377       //     vmov s0, s3 -> vext.32 d0, d0, d0, #1  vext.32 d0, d1, d0, #1
   4378       //     vmov s1, s2 -> vext.32 d0, d0, d0, #1  vext.32 d0, d0, d1, #1
   4379       //
   4380       // Pattern of the MachineInstrs is:
   4381       //     %DDst = VEXTd32 %DSrc1, %DSrc2, Lane, 14, %noreg (;implicits)
   4382       MachineInstrBuilder NewMIB;
   4383       NewMIB = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(),
   4384                        get(ARM::VEXTd32), DDst);
   4385 
   4386       // On the first instruction, both DSrc and DDst may be <undef> if present.
   4387       // Specifically when the original instruction didn't have them as an
   4388       // <imp-use>.
   4389       unsigned CurReg = SrcLane == 1 && DstLane == 1 ? DSrc : DDst;
   4390       bool CurUndef = !MI->readsRegister(CurReg, TRI);
   4391       NewMIB.addReg(CurReg, getUndefRegState(CurUndef));
   4392 
   4393       CurReg = SrcLane == 0 && DstLane == 0 ? DSrc : DDst;
   4394       CurUndef = !MI->readsRegister(CurReg, TRI);
   4395       NewMIB.addReg(CurReg, getUndefRegState(CurUndef));
   4396 
   4397       NewMIB.addImm(1);
   4398       AddDefaultPred(NewMIB);
   4399 
   4400       if (SrcLane == DstLane)
   4401         NewMIB.addReg(SrcReg, RegState::Implicit);
   4402 
   4403       MI->setDesc(get(ARM::VEXTd32));
   4404       MIB.addReg(DDst, RegState::Define);
   4405 
   4406       // On the second instruction, DDst has definitely been defined above, so
   4407       // it is not <undef>. DSrc, if present, can be <undef> as above.
   4408       CurReg = SrcLane == 1 && DstLane == 0 ? DSrc : DDst;
   4409       CurUndef = CurReg == DSrc && !MI->readsRegister(CurReg, TRI);
   4410       MIB.addReg(CurReg, getUndefRegState(CurUndef));
   4411 
   4412       CurReg = SrcLane == 0 && DstLane == 1 ? DSrc : DDst;
   4413       CurUndef = CurReg == DSrc && !MI->readsRegister(CurReg, TRI);
   4414       MIB.addReg(CurReg, getUndefRegState(CurUndef));
   4415 
   4416       MIB.addImm(1);
   4417       AddDefaultPred(MIB);
   4418 
   4419       if (SrcLane != DstLane)
   4420         MIB.addReg(SrcReg, RegState::Implicit);
   4421 
   4422       // As before, the original destination is no longer represented, add it
   4423       // implicitly.
   4424       MIB.addReg(DstReg, RegState::Define | RegState::Implicit);
   4425       if (ImplicitSReg != 0)
   4426         MIB.addReg(ImplicitSReg, RegState::Implicit);
   4427       break;
   4428     }
   4429   }
   4430 
   4431 }
   4432 
   4433 //===----------------------------------------------------------------------===//
   4434 // Partial register updates
   4435 //===----------------------------------------------------------------------===//
   4436 //
   4437 // Swift renames NEON registers with 64-bit granularity.  That means any
   4438 // instruction writing an S-reg implicitly reads the containing D-reg.  The
   4439 // problem is mostly avoided by translating f32 operations to v2f32 operations
   4440 // on D-registers, but f32 loads are still a problem.
   4441 //
   4442 // These instructions can load an f32 into a NEON register:
   4443 //
   4444 // VLDRS - Only writes S, partial D update.
   4445 // VLD1LNd32 - Writes all D-regs, explicit partial D update, 2 uops.
   4446 // VLD1DUPd32 - Writes all D-regs, no partial reg update, 2 uops.
   4447 //
   4448 // FCONSTD can be used as a dependency-breaking instruction.
   4449 unsigned ARMBaseInstrInfo::
   4450 getPartialRegUpdateClearance(const MachineInstr *MI,
   4451                              unsigned OpNum,
   4452                              const TargetRegisterInfo *TRI) const {
   4453   if (!SwiftPartialUpdateClearance ||
   4454       !(Subtarget.isSwift() || Subtarget.isCortexA15()))
   4455     return 0;
   4456 
   4457   assert(TRI && "Need TRI instance");
   4458 
   4459   const MachineOperand &MO = MI->getOperand(OpNum);
   4460   if (MO.readsReg())
   4461     return 0;
   4462   unsigned Reg = MO.getReg();
   4463   int UseOp = -1;
   4464 
   4465   switch(MI->getOpcode()) {
   4466     // Normal instructions writing only an S-register.
   4467   case ARM::VLDRS:
   4468   case ARM::FCONSTS:
   4469   case ARM::VMOVSR:
   4470   case ARM::VMOVv8i8:
   4471   case ARM::VMOVv4i16:
   4472   case ARM::VMOVv2i32:
   4473   case ARM::VMOVv2f32:
   4474   case ARM::VMOVv1i64:
   4475     UseOp = MI->findRegisterUseOperandIdx(Reg, false, TRI);
   4476     break;
   4477 
   4478     // Explicitly reads the dependency.
   4479   case ARM::VLD1LNd32:
   4480     UseOp = 3;
   4481     break;
   4482   default:
   4483     return 0;
   4484   }
   4485 
   4486   // If this instruction actually reads a value from Reg, there is no unwanted
   4487   // dependency.
   4488   if (UseOp != -1 && MI->getOperand(UseOp).readsReg())
   4489     return 0;
   4490 
   4491   // We must be able to clobber the whole D-reg.
   4492   if (TargetRegisterInfo::isVirtualRegister(Reg)) {
   4493     // Virtual register must be a foo:ssub_0<def,undef> operand.
   4494     if (!MO.getSubReg() || MI->readsVirtualRegister(Reg))
   4495       return 0;
   4496   } else if (ARM::SPRRegClass.contains(Reg)) {
   4497     // Physical register: MI must define the full D-reg.
   4498     unsigned DReg = TRI->getMatchingSuperReg(Reg, ARM::ssub_0,
   4499                                              &ARM::DPRRegClass);
   4500     if (!DReg || !MI->definesRegister(DReg, TRI))
   4501       return 0;
   4502   }
   4503 
   4504   // MI has an unwanted D-register dependency.
   4505   // Avoid defs in the previous N instructrions.
   4506   return SwiftPartialUpdateClearance;
   4507 }
   4508 
   4509 // Break a partial register dependency after getPartialRegUpdateClearance
   4510 // returned non-zero.
   4511 void ARMBaseInstrInfo::
   4512 breakPartialRegDependency(MachineBasicBlock::iterator MI,
   4513                           unsigned OpNum,
   4514                           const TargetRegisterInfo *TRI) const {
   4515   assert(MI && OpNum < MI->getDesc().getNumDefs() && "OpNum is not a def");
   4516   assert(TRI && "Need TRI instance");
   4517 
   4518   const MachineOperand &MO = MI->getOperand(OpNum);
   4519   unsigned Reg = MO.getReg();
   4520   assert(TargetRegisterInfo::isPhysicalRegister(Reg) &&
   4521          "Can't break virtual register dependencies.");
   4522   unsigned DReg = Reg;
   4523 
   4524   // If MI defines an S-reg, find the corresponding D super-register.
   4525   if (ARM::SPRRegClass.contains(Reg)) {
   4526     DReg = ARM::D0 + (Reg - ARM::S0) / 2;
   4527     assert(TRI->isSuperRegister(Reg, DReg) && "Register enums broken");
   4528   }
   4529 
   4530   assert(ARM::DPRRegClass.contains(DReg) && "Can only break D-reg deps");
   4531   assert(MI->definesRegister(DReg, TRI) && "MI doesn't clobber full D-reg");
   4532 
   4533   // FIXME: In some cases, VLDRS can be changed to a VLD1DUPd32 which defines
   4534   // the full D-register by loading the same value to both lanes.  The
   4535   // instruction is micro-coded with 2 uops, so don't do this until we can
   4536   // properly schedule micro-coded instructions.  The dispatcher stalls cause
   4537   // too big regressions.
   4538 
   4539   // Insert the dependency-breaking FCONSTD before MI.
   4540   // 96 is the encoding of 0.5, but the actual value doesn't matter here.
   4541   AddDefaultPred(BuildMI(*MI->getParent(), MI, MI->getDebugLoc(),
   4542                          get(ARM::FCONSTD), DReg).addImm(96));
   4543   MI->addRegisterKilled(DReg, TRI, true);
   4544 }
   4545 
   4546 bool ARMBaseInstrInfo::hasNOP() const {
   4547   return Subtarget.getFeatureBits()[ARM::HasV6KOps];
   4548 }
   4549 
   4550 bool ARMBaseInstrInfo::isSwiftFastImmShift(const MachineInstr *MI) const {
   4551   if (MI->getNumOperands() < 4)
   4552     return true;
   4553   unsigned ShOpVal = MI->getOperand(3).getImm();
   4554   unsigned ShImm = ARM_AM::getSORegOffset(ShOpVal);
   4555   // Swift supports faster shifts for: lsl 2, lsl 1, and lsr 1.
   4556   if ((ShImm == 1 && ARM_AM::getSORegShOp(ShOpVal) == ARM_AM::lsr) ||
   4557       ((ShImm == 1 || ShImm == 2) &&
   4558        ARM_AM::getSORegShOp(ShOpVal) == ARM_AM::lsl))
   4559     return true;
   4560 
   4561   return false;
   4562 }
   4563 
   4564 bool ARMBaseInstrInfo::getRegSequenceLikeInputs(
   4565     const MachineInstr &MI, unsigned DefIdx,
   4566     SmallVectorImpl<RegSubRegPairAndIdx> &InputRegs) const {
   4567   assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index");
   4568   assert(MI.isRegSequenceLike() && "Invalid kind of instruction");
   4569 
   4570   switch (MI.getOpcode()) {
   4571   case ARM::VMOVDRR:
   4572     // dX = VMOVDRR rY, rZ
   4573     // is the same as:
   4574     // dX = REG_SEQUENCE rY, ssub_0, rZ, ssub_1
   4575     // Populate the InputRegs accordingly.
   4576     // rY
   4577     const MachineOperand *MOReg = &MI.getOperand(1);
   4578     InputRegs.push_back(
   4579         RegSubRegPairAndIdx(MOReg->getReg(), MOReg->getSubReg(), ARM::ssub_0));
   4580     // rZ
   4581     MOReg = &MI.getOperand(2);
   4582     InputRegs.push_back(
   4583         RegSubRegPairAndIdx(MOReg->getReg(), MOReg->getSubReg(), ARM::ssub_1));
   4584     return true;
   4585   }
   4586   llvm_unreachable("Target dependent opcode missing");
   4587 }
   4588 
   4589 bool ARMBaseInstrInfo::getExtractSubregLikeInputs(
   4590     const MachineInstr &MI, unsigned DefIdx,
   4591     RegSubRegPairAndIdx &InputReg) const {
   4592   assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index");
   4593   assert(MI.isExtractSubregLike() && "Invalid kind of instruction");
   4594 
   4595   switch (MI.getOpcode()) {
   4596   case ARM::VMOVRRD:
   4597     // rX, rY = VMOVRRD dZ
   4598     // is the same as:
   4599     // rX = EXTRACT_SUBREG dZ, ssub_0
   4600     // rY = EXTRACT_SUBREG dZ, ssub_1
   4601     const MachineOperand &MOReg = MI.getOperand(2);
   4602     InputReg.Reg = MOReg.getReg();
   4603     InputReg.SubReg = MOReg.getSubReg();
   4604     InputReg.SubIdx = DefIdx == 0 ? ARM::ssub_0 : ARM::ssub_1;
   4605     return true;
   4606   }
   4607   llvm_unreachable("Target dependent opcode missing");
   4608 }
   4609 
   4610 bool ARMBaseInstrInfo::getInsertSubregLikeInputs(
   4611     const MachineInstr &MI, unsigned DefIdx, RegSubRegPair &BaseReg,
   4612     RegSubRegPairAndIdx &InsertedReg) const {
   4613   assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index");
   4614   assert(MI.isInsertSubregLike() && "Invalid kind of instruction");
   4615 
   4616   switch (MI.getOpcode()) {
   4617   case ARM::VSETLNi32:
   4618     // dX = VSETLNi32 dY, rZ, imm
   4619     const MachineOperand &MOBaseReg = MI.getOperand(1);
   4620     const MachineOperand &MOInsertedReg = MI.getOperand(2);
   4621     const MachineOperand &MOIndex = MI.getOperand(3);
   4622     BaseReg.Reg = MOBaseReg.getReg();
   4623     BaseReg.SubReg = MOBaseReg.getSubReg();
   4624 
   4625     InsertedReg.Reg = MOInsertedReg.getReg();
   4626     InsertedReg.SubReg = MOInsertedReg.getSubReg();
   4627     InsertedReg.SubIdx = MOIndex.getImm() == 0 ? ARM::ssub_0 : ARM::ssub_1;
   4628     return true;
   4629   }
   4630   llvm_unreachable("Target dependent opcode missing");
   4631 }
   4632