ARMBaseInstrInfo.cpp revision a9fa4fd9736f7d1066223f32fa54efbe86c0fceb
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 "ARMBaseInstrInfo.h"
15#include "ARM.h"
16#include "ARMBaseRegisterInfo.h"
17#include "ARMConstantPoolValue.h"
18#include "ARMHazardRecognizer.h"
19#include "ARMMachineFunctionInfo.h"
20#include "MCTargetDesc/ARMAddressingModes.h"
21#include "llvm/Constants.h"
22#include "llvm/Function.h"
23#include "llvm/GlobalValue.h"
24#include "llvm/CodeGen/LiveVariables.h"
25#include "llvm/CodeGen/MachineConstantPool.h"
26#include "llvm/CodeGen/MachineFrameInfo.h"
27#include "llvm/CodeGen/MachineInstrBuilder.h"
28#include "llvm/CodeGen/MachineJumpTableInfo.h"
29#include "llvm/CodeGen/MachineMemOperand.h"
30#include "llvm/CodeGen/MachineRegisterInfo.h"
31#include "llvm/CodeGen/SelectionDAGNodes.h"
32#include "llvm/MC/MCAsmInfo.h"
33#include "llvm/Support/BranchProbability.h"
34#include "llvm/Support/CommandLine.h"
35#include "llvm/Support/Debug.h"
36#include "llvm/Support/ErrorHandling.h"
37#include "llvm/ADT/STLExtras.h"
38
39#define GET_INSTRINFO_CTOR
40#include "ARMGenInstrInfo.inc"
41
42using namespace llvm;
43
44static cl::opt<bool>
45EnableARM3Addr("enable-arm-3-addr-conv", cl::Hidden,
46               cl::desc("Enable ARM 2-addr to 3-addr conv"));
47
48static cl::opt<bool>
49WidenVMOVS("widen-vmovs", cl::Hidden, cl::init(true),
50           cl::desc("Widen ARM vmovs to vmovd when possible"));
51
52static cl::opt<unsigned>
53SwiftPartialUpdateClearance("swift-partial-update-clearance",
54     cl::Hidden, cl::init(12),
55     cl::desc("Clearance before partial register updates"));
56
57/// ARM_MLxEntry - Record information about MLA / MLS instructions.
58struct ARM_MLxEntry {
59  uint16_t MLxOpc;     // MLA / MLS opcode
60  uint16_t MulOpc;     // Expanded multiplication opcode
61  uint16_t AddSubOpc;  // Expanded add / sub opcode
62  bool NegAcc;         // True if the acc is negated before the add / sub.
63  bool HasLane;        // True if instruction has an extra "lane" operand.
64};
65
66static const ARM_MLxEntry ARM_MLxTable[] = {
67  // MLxOpc,          MulOpc,           AddSubOpc,       NegAcc, HasLane
68  // fp scalar ops
69  { ARM::VMLAS,       ARM::VMULS,       ARM::VADDS,      false,  false },
70  { ARM::VMLSS,       ARM::VMULS,       ARM::VSUBS,      false,  false },
71  { ARM::VMLAD,       ARM::VMULD,       ARM::VADDD,      false,  false },
72  { ARM::VMLSD,       ARM::VMULD,       ARM::VSUBD,      false,  false },
73  { ARM::VNMLAS,      ARM::VNMULS,      ARM::VSUBS,      true,   false },
74  { ARM::VNMLSS,      ARM::VMULS,       ARM::VSUBS,      true,   false },
75  { ARM::VNMLAD,      ARM::VNMULD,      ARM::VSUBD,      true,   false },
76  { ARM::VNMLSD,      ARM::VMULD,       ARM::VSUBD,      true,   false },
77
78  // fp SIMD ops
79  { ARM::VMLAfd,      ARM::VMULfd,      ARM::VADDfd,     false,  false },
80  { ARM::VMLSfd,      ARM::VMULfd,      ARM::VSUBfd,     false,  false },
81  { ARM::VMLAfq,      ARM::VMULfq,      ARM::VADDfq,     false,  false },
82  { ARM::VMLSfq,      ARM::VMULfq,      ARM::VSUBfq,     false,  false },
83  { ARM::VMLAslfd,    ARM::VMULslfd,    ARM::VADDfd,     false,  true  },
84  { ARM::VMLSslfd,    ARM::VMULslfd,    ARM::VSUBfd,     false,  true  },
85  { ARM::VMLAslfq,    ARM::VMULslfq,    ARM::VADDfq,     false,  true  },
86  { ARM::VMLSslfq,    ARM::VMULslfq,    ARM::VSUBfq,     false,  true  },
87};
88
89ARMBaseInstrInfo::ARMBaseInstrInfo(const ARMSubtarget& STI)
90  : ARMGenInstrInfo(ARM::ADJCALLSTACKDOWN, ARM::ADJCALLSTACKUP),
91    Subtarget(STI) {
92  for (unsigned i = 0, e = array_lengthof(ARM_MLxTable); i != e; ++i) {
93    if (!MLxEntryMap.insert(std::make_pair(ARM_MLxTable[i].MLxOpc, i)).second)
94      assert(false && "Duplicated entries?");
95    MLxHazardOpcodes.insert(ARM_MLxTable[i].AddSubOpc);
96    MLxHazardOpcodes.insert(ARM_MLxTable[i].MulOpc);
97  }
98}
99
100// Use a ScoreboardHazardRecognizer for prepass ARM scheduling. TargetInstrImpl
101// currently defaults to no prepass hazard recognizer.
102ScheduleHazardRecognizer *ARMBaseInstrInfo::
103CreateTargetHazardRecognizer(const TargetMachine *TM,
104                             const ScheduleDAG *DAG) const {
105  if (usePreRAHazardRecognizer()) {
106    const InstrItineraryData *II = TM->getInstrItineraryData();
107    return new ScoreboardHazardRecognizer(II, DAG, "pre-RA-sched");
108  }
109  return TargetInstrInfo::CreateTargetHazardRecognizer(TM, DAG);
110}
111
112ScheduleHazardRecognizer *ARMBaseInstrInfo::
113CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II,
114                                   const ScheduleDAG *DAG) const {
115  if (Subtarget.isThumb2() || Subtarget.hasVFP2())
116    return (ScheduleHazardRecognizer *)
117      new ARMHazardRecognizer(II, *this, getRegisterInfo(), Subtarget, DAG);
118  return TargetInstrInfo::CreateTargetPostRAHazardRecognizer(II, DAG);
119}
120
121MachineInstr *
122ARMBaseInstrInfo::convertToThreeAddress(MachineFunction::iterator &MFI,
123                                        MachineBasicBlock::iterator &MBBI,
124                                        LiveVariables *LV) const {
125  // FIXME: Thumb2 support.
126
127  if (!EnableARM3Addr)
128    return NULL;
129
130  MachineInstr *MI = MBBI;
131  MachineFunction &MF = *MI->getParent()->getParent();
132  uint64_t TSFlags = MI->getDesc().TSFlags;
133  bool isPre = false;
134  switch ((TSFlags & ARMII::IndexModeMask) >> ARMII::IndexModeShift) {
135  default: return NULL;
136  case ARMII::IndexModePre:
137    isPre = true;
138    break;
139  case ARMII::IndexModePost:
140    break;
141  }
142
143  // Try splitting an indexed load/store to an un-indexed one plus an add/sub
144  // operation.
145  unsigned MemOpc = getUnindexedOpcode(MI->getOpcode());
146  if (MemOpc == 0)
147    return NULL;
148
149  MachineInstr *UpdateMI = NULL;
150  MachineInstr *MemMI = NULL;
151  unsigned AddrMode = (TSFlags & ARMII::AddrModeMask);
152  const MCInstrDesc &MCID = MI->getDesc();
153  unsigned NumOps = MCID.getNumOperands();
154  bool isLoad = !MI->mayStore();
155  const MachineOperand &WB = isLoad ? MI->getOperand(1) : MI->getOperand(0);
156  const MachineOperand &Base = MI->getOperand(2);
157  const MachineOperand &Offset = MI->getOperand(NumOps-3);
158  unsigned WBReg = WB.getReg();
159  unsigned BaseReg = Base.getReg();
160  unsigned OffReg = Offset.getReg();
161  unsigned OffImm = MI->getOperand(NumOps-2).getImm();
162  ARMCC::CondCodes Pred = (ARMCC::CondCodes)MI->getOperand(NumOps-1).getImm();
163  switch (AddrMode) {
164  default: llvm_unreachable("Unknown indexed op!");
165  case ARMII::AddrMode2: {
166    bool isSub = ARM_AM::getAM2Op(OffImm) == ARM_AM::sub;
167    unsigned Amt = ARM_AM::getAM2Offset(OffImm);
168    if (OffReg == 0) {
169      if (ARM_AM::getSOImmVal(Amt) == -1)
170        // Can't encode it in a so_imm operand. This transformation will
171        // add more than 1 instruction. Abandon!
172        return NULL;
173      UpdateMI = BuildMI(MF, MI->getDebugLoc(),
174                         get(isSub ? ARM::SUBri : ARM::ADDri), WBReg)
175        .addReg(BaseReg).addImm(Amt)
176        .addImm(Pred).addReg(0).addReg(0);
177    } else if (Amt != 0) {
178      ARM_AM::ShiftOpc ShOpc = ARM_AM::getAM2ShiftOpc(OffImm);
179      unsigned SOOpc = ARM_AM::getSORegOpc(ShOpc, Amt);
180      UpdateMI = BuildMI(MF, MI->getDebugLoc(),
181                         get(isSub ? ARM::SUBrsi : ARM::ADDrsi), WBReg)
182        .addReg(BaseReg).addReg(OffReg).addReg(0).addImm(SOOpc)
183        .addImm(Pred).addReg(0).addReg(0);
184    } else
185      UpdateMI = BuildMI(MF, MI->getDebugLoc(),
186                         get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg)
187        .addReg(BaseReg).addReg(OffReg)
188        .addImm(Pred).addReg(0).addReg(0);
189    break;
190  }
191  case ARMII::AddrMode3 : {
192    bool isSub = ARM_AM::getAM3Op(OffImm) == ARM_AM::sub;
193    unsigned Amt = ARM_AM::getAM3Offset(OffImm);
194    if (OffReg == 0)
195      // Immediate is 8-bits. It's guaranteed to fit in a so_imm operand.
196      UpdateMI = BuildMI(MF, MI->getDebugLoc(),
197                         get(isSub ? ARM::SUBri : ARM::ADDri), WBReg)
198        .addReg(BaseReg).addImm(Amt)
199        .addImm(Pred).addReg(0).addReg(0);
200    else
201      UpdateMI = BuildMI(MF, MI->getDebugLoc(),
202                         get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg)
203        .addReg(BaseReg).addReg(OffReg)
204        .addImm(Pred).addReg(0).addReg(0);
205    break;
206  }
207  }
208
209  std::vector<MachineInstr*> NewMIs;
210  if (isPre) {
211    if (isLoad)
212      MemMI = BuildMI(MF, MI->getDebugLoc(),
213                      get(MemOpc), MI->getOperand(0).getReg())
214        .addReg(WBReg).addImm(0).addImm(Pred);
215    else
216      MemMI = BuildMI(MF, MI->getDebugLoc(),
217                      get(MemOpc)).addReg(MI->getOperand(1).getReg())
218        .addReg(WBReg).addReg(0).addImm(0).addImm(Pred);
219    NewMIs.push_back(MemMI);
220    NewMIs.push_back(UpdateMI);
221  } else {
222    if (isLoad)
223      MemMI = BuildMI(MF, MI->getDebugLoc(),
224                      get(MemOpc), MI->getOperand(0).getReg())
225        .addReg(BaseReg).addImm(0).addImm(Pred);
226    else
227      MemMI = BuildMI(MF, MI->getDebugLoc(),
228                      get(MemOpc)).addReg(MI->getOperand(1).getReg())
229        .addReg(BaseReg).addReg(0).addImm(0).addImm(Pred);
230    if (WB.isDead())
231      UpdateMI->getOperand(0).setIsDead();
232    NewMIs.push_back(UpdateMI);
233    NewMIs.push_back(MemMI);
234  }
235
236  // Transfer LiveVariables states, kill / dead info.
237  if (LV) {
238    for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
239      MachineOperand &MO = MI->getOperand(i);
240      if (MO.isReg() && TargetRegisterInfo::isVirtualRegister(MO.getReg())) {
241        unsigned Reg = MO.getReg();
242
243        LiveVariables::VarInfo &VI = LV->getVarInfo(Reg);
244        if (MO.isDef()) {
245          MachineInstr *NewMI = (Reg == WBReg) ? UpdateMI : MemMI;
246          if (MO.isDead())
247            LV->addVirtualRegisterDead(Reg, NewMI);
248        }
249        if (MO.isUse() && MO.isKill()) {
250          for (unsigned j = 0; j < 2; ++j) {
251            // Look at the two new MI's in reverse order.
252            MachineInstr *NewMI = NewMIs[j];
253            if (!NewMI->readsRegister(Reg))
254              continue;
255            LV->addVirtualRegisterKilled(Reg, NewMI);
256            if (VI.removeKill(MI))
257              VI.Kills.push_back(NewMI);
258            break;
259          }
260        }
261      }
262    }
263  }
264
265  MFI->insert(MBBI, NewMIs[1]);
266  MFI->insert(MBBI, NewMIs[0]);
267  return NewMIs[0];
268}
269
270// Branch analysis.
271bool
272ARMBaseInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB,
273                                MachineBasicBlock *&FBB,
274                                SmallVectorImpl<MachineOperand> &Cond,
275                                bool AllowModify) const {
276  // If the block has no terminators, it just falls into the block after it.
277  MachineBasicBlock::iterator I = MBB.end();
278  if (I == MBB.begin())
279    return false;
280  --I;
281  while (I->isDebugValue()) {
282    if (I == MBB.begin())
283      return false;
284    --I;
285  }
286  if (!isUnpredicatedTerminator(I))
287    return false;
288
289  // Get the last instruction in the block.
290  MachineInstr *LastInst = I;
291
292  // If there is only one terminator instruction, process it.
293  unsigned LastOpc = LastInst->getOpcode();
294  if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) {
295    if (isUncondBranchOpcode(LastOpc)) {
296      TBB = LastInst->getOperand(0).getMBB();
297      return false;
298    }
299    if (isCondBranchOpcode(LastOpc)) {
300      // Block ends with fall-through condbranch.
301      TBB = LastInst->getOperand(0).getMBB();
302      Cond.push_back(LastInst->getOperand(1));
303      Cond.push_back(LastInst->getOperand(2));
304      return false;
305    }
306    return true;  // Can't handle indirect branch.
307  }
308
309  // Get the instruction before it if it is a terminator.
310  MachineInstr *SecondLastInst = I;
311  unsigned SecondLastOpc = SecondLastInst->getOpcode();
312
313  // If AllowModify is true and the block ends with two or more unconditional
314  // branches, delete all but the first unconditional branch.
315  if (AllowModify && isUncondBranchOpcode(LastOpc)) {
316    while (isUncondBranchOpcode(SecondLastOpc)) {
317      LastInst->eraseFromParent();
318      LastInst = SecondLastInst;
319      LastOpc = LastInst->getOpcode();
320      if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) {
321        // Return now the only terminator is an unconditional branch.
322        TBB = LastInst->getOperand(0).getMBB();
323        return false;
324      } else {
325        SecondLastInst = I;
326        SecondLastOpc = SecondLastInst->getOpcode();
327      }
328    }
329  }
330
331  // If there are three terminators, we don't know what sort of block this is.
332  if (SecondLastInst && I != MBB.begin() && isUnpredicatedTerminator(--I))
333    return true;
334
335  // If the block ends with a B and a Bcc, handle it.
336  if (isCondBranchOpcode(SecondLastOpc) && isUncondBranchOpcode(LastOpc)) {
337    TBB =  SecondLastInst->getOperand(0).getMBB();
338    Cond.push_back(SecondLastInst->getOperand(1));
339    Cond.push_back(SecondLastInst->getOperand(2));
340    FBB = LastInst->getOperand(0).getMBB();
341    return false;
342  }
343
344  // If the block ends with two unconditional branches, handle it.  The second
345  // one is not executed, so remove it.
346  if (isUncondBranchOpcode(SecondLastOpc) && isUncondBranchOpcode(LastOpc)) {
347    TBB = SecondLastInst->getOperand(0).getMBB();
348    I = LastInst;
349    if (AllowModify)
350      I->eraseFromParent();
351    return false;
352  }
353
354  // ...likewise if it ends with a branch table followed by an unconditional
355  // branch. The branch folder can create these, and we must get rid of them for
356  // correctness of Thumb constant islands.
357  if ((isJumpTableBranchOpcode(SecondLastOpc) ||
358       isIndirectBranchOpcode(SecondLastOpc)) &&
359      isUncondBranchOpcode(LastOpc)) {
360    I = LastInst;
361    if (AllowModify)
362      I->eraseFromParent();
363    return true;
364  }
365
366  // Otherwise, can't handle this.
367  return true;
368}
369
370
371unsigned ARMBaseInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const {
372  MachineBasicBlock::iterator I = MBB.end();
373  if (I == MBB.begin()) return 0;
374  --I;
375  while (I->isDebugValue()) {
376    if (I == MBB.begin())
377      return 0;
378    --I;
379  }
380  if (!isUncondBranchOpcode(I->getOpcode()) &&
381      !isCondBranchOpcode(I->getOpcode()))
382    return 0;
383
384  // Remove the branch.
385  I->eraseFromParent();
386
387  I = MBB.end();
388
389  if (I == MBB.begin()) return 1;
390  --I;
391  if (!isCondBranchOpcode(I->getOpcode()))
392    return 1;
393
394  // Remove the branch.
395  I->eraseFromParent();
396  return 2;
397}
398
399unsigned
400ARMBaseInstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
401                               MachineBasicBlock *FBB,
402                               const SmallVectorImpl<MachineOperand> &Cond,
403                               DebugLoc DL) const {
404  ARMFunctionInfo *AFI = MBB.getParent()->getInfo<ARMFunctionInfo>();
405  int BOpc   = !AFI->isThumbFunction()
406    ? ARM::B : (AFI->isThumb2Function() ? ARM::t2B : ARM::tB);
407  int BccOpc = !AFI->isThumbFunction()
408    ? ARM::Bcc : (AFI->isThumb2Function() ? ARM::t2Bcc : ARM::tBcc);
409  bool isThumb = AFI->isThumbFunction() || AFI->isThumb2Function();
410
411  // Shouldn't be a fall through.
412  assert(TBB && "InsertBranch must not be told to insert a fallthrough");
413  assert((Cond.size() == 2 || Cond.size() == 0) &&
414         "ARM branch conditions have two components!");
415
416  if (FBB == 0) {
417    if (Cond.empty()) { // Unconditional branch?
418      if (isThumb)
419        BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB).addImm(ARMCC::AL).addReg(0);
420      else
421        BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB);
422    } else
423      BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB)
424        .addImm(Cond[0].getImm()).addReg(Cond[1].getReg());
425    return 1;
426  }
427
428  // Two-way conditional branch.
429  BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB)
430    .addImm(Cond[0].getImm()).addReg(Cond[1].getReg());
431  if (isThumb)
432    BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB).addImm(ARMCC::AL).addReg(0);
433  else
434    BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB);
435  return 2;
436}
437
438bool ARMBaseInstrInfo::
439ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const {
440  ARMCC::CondCodes CC = (ARMCC::CondCodes)(int)Cond[0].getImm();
441  Cond[0].setImm(ARMCC::getOppositeCondition(CC));
442  return false;
443}
444
445bool ARMBaseInstrInfo::isPredicated(const MachineInstr *MI) const {
446  if (MI->isBundle()) {
447    MachineBasicBlock::const_instr_iterator I = MI;
448    MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
449    while (++I != E && I->isInsideBundle()) {
450      int PIdx = I->findFirstPredOperandIdx();
451      if (PIdx != -1 && I->getOperand(PIdx).getImm() != ARMCC::AL)
452        return true;
453    }
454    return false;
455  }
456
457  int PIdx = MI->findFirstPredOperandIdx();
458  return PIdx != -1 && MI->getOperand(PIdx).getImm() != ARMCC::AL;
459}
460
461bool ARMBaseInstrInfo::
462PredicateInstruction(MachineInstr *MI,
463                     const SmallVectorImpl<MachineOperand> &Pred) const {
464  unsigned Opc = MI->getOpcode();
465  if (isUncondBranchOpcode(Opc)) {
466    MI->setDesc(get(getMatchingCondBranchOpcode(Opc)));
467    MI->addOperand(MachineOperand::CreateImm(Pred[0].getImm()));
468    MI->addOperand(MachineOperand::CreateReg(Pred[1].getReg(), false));
469    return true;
470  }
471
472  int PIdx = MI->findFirstPredOperandIdx();
473  if (PIdx != -1) {
474    MachineOperand &PMO = MI->getOperand(PIdx);
475    PMO.setImm(Pred[0].getImm());
476    MI->getOperand(PIdx+1).setReg(Pred[1].getReg());
477    return true;
478  }
479  return false;
480}
481
482bool ARMBaseInstrInfo::
483SubsumesPredicate(const SmallVectorImpl<MachineOperand> &Pred1,
484                  const SmallVectorImpl<MachineOperand> &Pred2) const {
485  if (Pred1.size() > 2 || Pred2.size() > 2)
486    return false;
487
488  ARMCC::CondCodes CC1 = (ARMCC::CondCodes)Pred1[0].getImm();
489  ARMCC::CondCodes CC2 = (ARMCC::CondCodes)Pred2[0].getImm();
490  if (CC1 == CC2)
491    return true;
492
493  switch (CC1) {
494  default:
495    return false;
496  case ARMCC::AL:
497    return true;
498  case ARMCC::HS:
499    return CC2 == ARMCC::HI;
500  case ARMCC::LS:
501    return CC2 == ARMCC::LO || CC2 == ARMCC::EQ;
502  case ARMCC::GE:
503    return CC2 == ARMCC::GT;
504  case ARMCC::LE:
505    return CC2 == ARMCC::LT;
506  }
507}
508
509bool ARMBaseInstrInfo::DefinesPredicate(MachineInstr *MI,
510                                    std::vector<MachineOperand> &Pred) const {
511  bool Found = false;
512  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
513    const MachineOperand &MO = MI->getOperand(i);
514    if ((MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) ||
515        (MO.isReg() && MO.isDef() && MO.getReg() == ARM::CPSR)) {
516      Pred.push_back(MO);
517      Found = true;
518    }
519  }
520
521  return Found;
522}
523
524/// isPredicable - Return true if the specified instruction can be predicated.
525/// By default, this returns true for every instruction with a
526/// PredicateOperand.
527bool ARMBaseInstrInfo::isPredicable(MachineInstr *MI) const {
528  if (!MI->isPredicable())
529    return false;
530
531  if ((MI->getDesc().TSFlags & ARMII::DomainMask) == ARMII::DomainNEON) {
532    ARMFunctionInfo *AFI =
533      MI->getParent()->getParent()->getInfo<ARMFunctionInfo>();
534    return AFI->isThumb2Function();
535  }
536  return true;
537}
538
539/// FIXME: Works around a gcc miscompilation with -fstrict-aliasing.
540LLVM_ATTRIBUTE_NOINLINE
541static unsigned getNumJTEntries(const std::vector<MachineJumpTableEntry> &JT,
542                                unsigned JTI);
543static unsigned getNumJTEntries(const std::vector<MachineJumpTableEntry> &JT,
544                                unsigned JTI) {
545  assert(JTI < JT.size());
546  return JT[JTI].MBBs.size();
547}
548
549/// GetInstSize - Return the size of the specified MachineInstr.
550///
551unsigned ARMBaseInstrInfo::GetInstSizeInBytes(const MachineInstr *MI) const {
552  const MachineBasicBlock &MBB = *MI->getParent();
553  const MachineFunction *MF = MBB.getParent();
554  const MCAsmInfo *MAI = MF->getTarget().getMCAsmInfo();
555
556  const MCInstrDesc &MCID = MI->getDesc();
557  if (MCID.getSize())
558    return MCID.getSize();
559
560  // If this machine instr is an inline asm, measure it.
561  if (MI->getOpcode() == ARM::INLINEASM)
562    return getInlineAsmLength(MI->getOperand(0).getSymbolName(), *MAI);
563  if (MI->isLabel())
564    return 0;
565  unsigned Opc = MI->getOpcode();
566  switch (Opc) {
567  case TargetOpcode::IMPLICIT_DEF:
568  case TargetOpcode::KILL:
569  case TargetOpcode::PROLOG_LABEL:
570  case TargetOpcode::EH_LABEL:
571  case TargetOpcode::DBG_VALUE:
572    return 0;
573  case TargetOpcode::BUNDLE:
574    return getInstBundleLength(MI);
575  case ARM::MOVi16_ga_pcrel:
576  case ARM::MOVTi16_ga_pcrel:
577  case ARM::t2MOVi16_ga_pcrel:
578  case ARM::t2MOVTi16_ga_pcrel:
579    return 4;
580  case ARM::MOVi32imm:
581  case ARM::t2MOVi32imm:
582    return 8;
583  case ARM::CONSTPOOL_ENTRY:
584    // If this machine instr is a constant pool entry, its size is recorded as
585    // operand #2.
586    return MI->getOperand(2).getImm();
587  case ARM::Int_eh_sjlj_longjmp:
588    return 16;
589  case ARM::tInt_eh_sjlj_longjmp:
590    return 10;
591  case ARM::Int_eh_sjlj_setjmp:
592  case ARM::Int_eh_sjlj_setjmp_nofp:
593    return 20;
594  case ARM::tInt_eh_sjlj_setjmp:
595  case ARM::t2Int_eh_sjlj_setjmp:
596  case ARM::t2Int_eh_sjlj_setjmp_nofp:
597    return 12;
598  case ARM::BR_JTr:
599  case ARM::BR_JTm:
600  case ARM::BR_JTadd:
601  case ARM::tBR_JTr:
602  case ARM::t2BR_JT:
603  case ARM::t2TBB_JT:
604  case ARM::t2TBH_JT: {
605    // These are jumptable branches, i.e. a branch followed by an inlined
606    // jumptable. The size is 4 + 4 * number of entries. For TBB, each
607    // entry is one byte; TBH two byte each.
608    unsigned EntrySize = (Opc == ARM::t2TBB_JT)
609      ? 1 : ((Opc == ARM::t2TBH_JT) ? 2 : 4);
610    unsigned NumOps = MCID.getNumOperands();
611    MachineOperand JTOP =
612      MI->getOperand(NumOps - (MI->isPredicable() ? 3 : 2));
613    unsigned JTI = JTOP.getIndex();
614    const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
615    assert(MJTI != 0);
616    const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
617    assert(JTI < JT.size());
618    // Thumb instructions are 2 byte aligned, but JT entries are 4 byte
619    // 4 aligned. The assembler / linker may add 2 byte padding just before
620    // the JT entries.  The size does not include this padding; the
621    // constant islands pass does separate bookkeeping for it.
622    // FIXME: If we know the size of the function is less than (1 << 16) *2
623    // bytes, we can use 16-bit entries instead. Then there won't be an
624    // alignment issue.
625    unsigned InstSize = (Opc == ARM::tBR_JTr || Opc == ARM::t2BR_JT) ? 2 : 4;
626    unsigned NumEntries = getNumJTEntries(JT, JTI);
627    if (Opc == ARM::t2TBB_JT && (NumEntries & 1))
628      // Make sure the instruction that follows TBB is 2-byte aligned.
629      // FIXME: Constant island pass should insert an "ALIGN" instruction
630      // instead.
631      ++NumEntries;
632    return NumEntries * EntrySize + InstSize;
633  }
634  default:
635    // Otherwise, pseudo-instruction sizes are zero.
636    return 0;
637  }
638}
639
640unsigned ARMBaseInstrInfo::getInstBundleLength(const MachineInstr *MI) const {
641  unsigned Size = 0;
642  MachineBasicBlock::const_instr_iterator I = MI;
643  MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
644  while (++I != E && I->isInsideBundle()) {
645    assert(!I->isBundle() && "No nested bundle!");
646    Size += GetInstSizeInBytes(&*I);
647  }
648  return Size;
649}
650
651void ARMBaseInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
652                                   MachineBasicBlock::iterator I, DebugLoc DL,
653                                   unsigned DestReg, unsigned SrcReg,
654                                   bool KillSrc) const {
655  bool GPRDest = ARM::GPRRegClass.contains(DestReg);
656  bool GPRSrc  = ARM::GPRRegClass.contains(SrcReg);
657
658  if (GPRDest && GPRSrc) {
659    AddDefaultCC(AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::MOVr), DestReg)
660                                  .addReg(SrcReg, getKillRegState(KillSrc))));
661    return;
662  }
663
664  bool SPRDest = ARM::SPRRegClass.contains(DestReg);
665  bool SPRSrc  = ARM::SPRRegClass.contains(SrcReg);
666
667  unsigned Opc = 0;
668  if (SPRDest && SPRSrc)
669    Opc = ARM::VMOVS;
670  else if (GPRDest && SPRSrc)
671    Opc = ARM::VMOVRS;
672  else if (SPRDest && GPRSrc)
673    Opc = ARM::VMOVSR;
674  else if (ARM::DPRRegClass.contains(DestReg, SrcReg))
675    Opc = ARM::VMOVD;
676  else if (ARM::QPRRegClass.contains(DestReg, SrcReg))
677    Opc = ARM::VORRq;
678
679  if (Opc) {
680    MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(Opc), DestReg);
681    MIB.addReg(SrcReg, getKillRegState(KillSrc));
682    if (Opc == ARM::VORRq)
683      MIB.addReg(SrcReg, getKillRegState(KillSrc));
684    AddDefaultPred(MIB);
685    return;
686  }
687
688  // Handle register classes that require multiple instructions.
689  unsigned BeginIdx = 0;
690  unsigned SubRegs = 0;
691  int Spacing = 1;
692
693  // Use VORRq when possible.
694  if (ARM::QQPRRegClass.contains(DestReg, SrcReg))
695    Opc = ARM::VORRq, BeginIdx = ARM::qsub_0, SubRegs = 2;
696  else if (ARM::QQQQPRRegClass.contains(DestReg, SrcReg))
697    Opc = ARM::VORRq, BeginIdx = ARM::qsub_0, SubRegs = 4;
698  // Fall back to VMOVD.
699  else if (ARM::DPairRegClass.contains(DestReg, SrcReg))
700    Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 2;
701  else if (ARM::DTripleRegClass.contains(DestReg, SrcReg))
702    Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 3;
703  else if (ARM::DQuadRegClass.contains(DestReg, SrcReg))
704    Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 4;
705  else if (ARM::GPRPairRegClass.contains(DestReg, SrcReg))
706    Opc = ARM::MOVr, BeginIdx = ARM::gsub_0, SubRegs = 2;
707
708  else if (ARM::DPairSpcRegClass.contains(DestReg, SrcReg))
709    Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 2, Spacing = 2;
710  else if (ARM::DTripleSpcRegClass.contains(DestReg, SrcReg))
711    Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 3, Spacing = 2;
712  else if (ARM::DQuadSpcRegClass.contains(DestReg, SrcReg))
713    Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 4, Spacing = 2;
714
715  assert(Opc && "Impossible reg-to-reg copy");
716
717  const TargetRegisterInfo *TRI = &getRegisterInfo();
718  MachineInstrBuilder Mov;
719
720  // Copy register tuples backward when the first Dest reg overlaps with SrcReg.
721  if (TRI->regsOverlap(SrcReg, TRI->getSubReg(DestReg, BeginIdx))) {
722    BeginIdx = BeginIdx + ((SubRegs-1)*Spacing);
723    Spacing = -Spacing;
724  }
725#ifndef NDEBUG
726  SmallSet<unsigned, 4> DstRegs;
727#endif
728  for (unsigned i = 0; i != SubRegs; ++i) {
729    unsigned Dst = TRI->getSubReg(DestReg, BeginIdx + i*Spacing);
730    unsigned Src = TRI->getSubReg(SrcReg,  BeginIdx + i*Spacing);
731    assert(Dst && Src && "Bad sub-register");
732#ifndef NDEBUG
733    assert(!DstRegs.count(Src) && "destructive vector copy");
734    DstRegs.insert(Dst);
735#endif
736    Mov = BuildMI(MBB, I, I->getDebugLoc(), get(Opc), Dst)
737      .addReg(Src);
738    // VORR takes two source operands.
739    if (Opc == ARM::VORRq)
740      Mov.addReg(Src);
741    Mov = AddDefaultPred(Mov);
742  }
743  // Add implicit super-register defs and kills to the last instruction.
744  Mov->addRegisterDefined(DestReg, TRI);
745  if (KillSrc)
746    Mov->addRegisterKilled(SrcReg, TRI);
747}
748
749static const
750MachineInstrBuilder &AddDReg(MachineInstrBuilder &MIB,
751                             unsigned Reg, unsigned SubIdx, unsigned State,
752                             const TargetRegisterInfo *TRI) {
753  if (!SubIdx)
754    return MIB.addReg(Reg, State);
755
756  if (TargetRegisterInfo::isPhysicalRegister(Reg))
757    return MIB.addReg(TRI->getSubReg(Reg, SubIdx), State);
758  return MIB.addReg(Reg, State, SubIdx);
759}
760
761void ARMBaseInstrInfo::
762storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
763                    unsigned SrcReg, bool isKill, int FI,
764                    const TargetRegisterClass *RC,
765                    const TargetRegisterInfo *TRI) const {
766  DebugLoc DL;
767  if (I != MBB.end()) DL = I->getDebugLoc();
768  MachineFunction &MF = *MBB.getParent();
769  MachineFrameInfo &MFI = *MF.getFrameInfo();
770  unsigned Align = MFI.getObjectAlignment(FI);
771
772  MachineMemOperand *MMO =
773    MF.getMachineMemOperand(MachinePointerInfo::getFixedStack(FI),
774                            MachineMemOperand::MOStore,
775                            MFI.getObjectSize(FI),
776                            Align);
777
778  switch (RC->getSize()) {
779    case 4:
780      if (ARM::GPRRegClass.hasSubClassEq(RC)) {
781        AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STRi12))
782                   .addReg(SrcReg, getKillRegState(isKill))
783                   .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
784      } else if (ARM::SPRRegClass.hasSubClassEq(RC)) {
785        AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRS))
786                   .addReg(SrcReg, getKillRegState(isKill))
787                   .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
788      } else
789        llvm_unreachable("Unknown reg class!");
790      break;
791    case 8:
792      if (ARM::DPRRegClass.hasSubClassEq(RC)) {
793        AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRD))
794                   .addReg(SrcReg, getKillRegState(isKill))
795                   .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
796      } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) {
797        MachineInstrBuilder MIB =
798          AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STMIA))
799                       .addFrameIndex(FI))
800                       .addMemOperand(MMO);
801          MIB = AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI);
802                AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI);
803      } else
804        llvm_unreachable("Unknown reg class!");
805      break;
806    case 16:
807      if (ARM::DPairRegClass.hasSubClassEq(RC)) {
808        // Use aligned spills if the stack can be realigned.
809        if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
810          AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1q64))
811                     .addFrameIndex(FI).addImm(16)
812                     .addReg(SrcReg, getKillRegState(isKill))
813                     .addMemOperand(MMO));
814        } else {
815          AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMQIA))
816                     .addReg(SrcReg, getKillRegState(isKill))
817                     .addFrameIndex(FI)
818                     .addMemOperand(MMO));
819        }
820      } else
821        llvm_unreachable("Unknown reg class!");
822      break;
823    case 24:
824      if (ARM::DTripleRegClass.hasSubClassEq(RC)) {
825        // Use aligned spills if the stack can be realigned.
826        if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
827          AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64TPseudo))
828                     .addFrameIndex(FI).addImm(16)
829                     .addReg(SrcReg, getKillRegState(isKill))
830                     .addMemOperand(MMO));
831        } else {
832          MachineInstrBuilder MIB =
833          AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA))
834                       .addFrameIndex(FI))
835                       .addMemOperand(MMO);
836          MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI);
837          MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI);
838          AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI);
839        }
840      } else
841        llvm_unreachable("Unknown reg class!");
842      break;
843    case 32:
844      if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) {
845        if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
846          // FIXME: It's possible to only store part of the QQ register if the
847          // spilled def has a sub-register index.
848          AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64QPseudo))
849                     .addFrameIndex(FI).addImm(16)
850                     .addReg(SrcReg, getKillRegState(isKill))
851                     .addMemOperand(MMO));
852        } else {
853          MachineInstrBuilder MIB =
854          AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA))
855                       .addFrameIndex(FI))
856                       .addMemOperand(MMO);
857          MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI);
858          MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI);
859          MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI);
860                AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI);
861        }
862      } else
863        llvm_unreachable("Unknown reg class!");
864      break;
865    case 64:
866      if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) {
867        MachineInstrBuilder MIB =
868          AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA))
869                         .addFrameIndex(FI))
870                         .addMemOperand(MMO);
871        MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI);
872        MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI);
873        MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI);
874        MIB = AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI);
875        MIB = AddDReg(MIB, SrcReg, ARM::dsub_4, 0, TRI);
876        MIB = AddDReg(MIB, SrcReg, ARM::dsub_5, 0, TRI);
877        MIB = AddDReg(MIB, SrcReg, ARM::dsub_6, 0, TRI);
878              AddDReg(MIB, SrcReg, ARM::dsub_7, 0, TRI);
879      } else
880        llvm_unreachable("Unknown reg class!");
881      break;
882    default:
883      llvm_unreachable("Unknown reg class!");
884  }
885}
886
887unsigned
888ARMBaseInstrInfo::isStoreToStackSlot(const MachineInstr *MI,
889                                     int &FrameIndex) const {
890  switch (MI->getOpcode()) {
891  default: break;
892  case ARM::STRrs:
893  case ARM::t2STRs: // FIXME: don't use t2STRs to access frame.
894    if (MI->getOperand(1).isFI() &&
895        MI->getOperand(2).isReg() &&
896        MI->getOperand(3).isImm() &&
897        MI->getOperand(2).getReg() == 0 &&
898        MI->getOperand(3).getImm() == 0) {
899      FrameIndex = MI->getOperand(1).getIndex();
900      return MI->getOperand(0).getReg();
901    }
902    break;
903  case ARM::STRi12:
904  case ARM::t2STRi12:
905  case ARM::tSTRspi:
906  case ARM::VSTRD:
907  case ARM::VSTRS:
908    if (MI->getOperand(1).isFI() &&
909        MI->getOperand(2).isImm() &&
910        MI->getOperand(2).getImm() == 0) {
911      FrameIndex = MI->getOperand(1).getIndex();
912      return MI->getOperand(0).getReg();
913    }
914    break;
915  case ARM::VST1q64:
916  case ARM::VST1d64TPseudo:
917  case ARM::VST1d64QPseudo:
918    if (MI->getOperand(0).isFI() &&
919        MI->getOperand(2).getSubReg() == 0) {
920      FrameIndex = MI->getOperand(0).getIndex();
921      return MI->getOperand(2).getReg();
922    }
923    break;
924  case ARM::VSTMQIA:
925    if (MI->getOperand(1).isFI() &&
926        MI->getOperand(0).getSubReg() == 0) {
927      FrameIndex = MI->getOperand(1).getIndex();
928      return MI->getOperand(0).getReg();
929    }
930    break;
931  }
932
933  return 0;
934}
935
936unsigned ARMBaseInstrInfo::isStoreToStackSlotPostFE(const MachineInstr *MI,
937                                                    int &FrameIndex) const {
938  const MachineMemOperand *Dummy;
939  return MI->mayStore() && hasStoreToStackSlot(MI, Dummy, FrameIndex);
940}
941
942void ARMBaseInstrInfo::
943loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
944                     unsigned DestReg, int FI,
945                     const TargetRegisterClass *RC,
946                     const TargetRegisterInfo *TRI) const {
947  DebugLoc DL;
948  if (I != MBB.end()) DL = I->getDebugLoc();
949  MachineFunction &MF = *MBB.getParent();
950  ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
951  MachineFrameInfo &MFI = *MF.getFrameInfo();
952  unsigned Align = MFI.getObjectAlignment(FI);
953  MachineMemOperand *MMO =
954    MF.getMachineMemOperand(
955                    MachinePointerInfo::getFixedStack(FI),
956                            MachineMemOperand::MOLoad,
957                            MFI.getObjectSize(FI),
958                            Align);
959
960  switch (RC->getSize()) {
961  case 4:
962    if (ARM::GPRRegClass.hasSubClassEq(RC)) {
963      AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::LDRi12), DestReg)
964                   .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
965
966    } else if (ARM::SPRRegClass.hasSubClassEq(RC)) {
967      AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRS), DestReg)
968                   .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
969    } else
970      llvm_unreachable("Unknown reg class!");
971    break;
972  case 8:
973    if (ARM::DPRRegClass.hasSubClassEq(RC)) {
974      AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRD), DestReg)
975                   .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
976    } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) {
977      unsigned LdmOpc = AFI->isThumbFunction() ? ARM::t2LDMIA : ARM::LDMIA;
978      MachineInstrBuilder MIB =
979        AddDefaultPred(BuildMI(MBB, I, DL, get(LdmOpc))
980                    .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
981      MIB = AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI);
982      MIB = AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI);
983      if (TargetRegisterInfo::isPhysicalRegister(DestReg))
984        MIB.addReg(DestReg, RegState::ImplicitDefine);
985    } else
986      llvm_unreachable("Unknown reg class!");
987    break;
988  case 16:
989    if (ARM::DPairRegClass.hasSubClassEq(RC)) {
990      if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
991        AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1q64), DestReg)
992                     .addFrameIndex(FI).addImm(16)
993                     .addMemOperand(MMO));
994      } else {
995        AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMQIA), DestReg)
996                       .addFrameIndex(FI)
997                       .addMemOperand(MMO));
998      }
999    } else
1000      llvm_unreachable("Unknown reg class!");
1001    break;
1002  case 24:
1003    if (ARM::DTripleRegClass.hasSubClassEq(RC)) {
1004      if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
1005        AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64TPseudo), DestReg)
1006                     .addFrameIndex(FI).addImm(16)
1007                     .addMemOperand(MMO));
1008      } else {
1009        MachineInstrBuilder MIB =
1010          AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA))
1011                         .addFrameIndex(FI)
1012                         .addMemOperand(MMO));
1013        MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI);
1014        MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI);
1015        MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI);
1016        if (TargetRegisterInfo::isPhysicalRegister(DestReg))
1017          MIB.addReg(DestReg, RegState::ImplicitDefine);
1018      }
1019    } else
1020      llvm_unreachable("Unknown reg class!");
1021    break;
1022   case 32:
1023    if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) {
1024      if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) {
1025        AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64QPseudo), DestReg)
1026                     .addFrameIndex(FI).addImm(16)
1027                     .addMemOperand(MMO));
1028      } else {
1029        MachineInstrBuilder MIB =
1030        AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA))
1031                       .addFrameIndex(FI))
1032                       .addMemOperand(MMO);
1033        MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI);
1034        MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI);
1035        MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI);
1036        MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI);
1037        if (TargetRegisterInfo::isPhysicalRegister(DestReg))
1038          MIB.addReg(DestReg, RegState::ImplicitDefine);
1039      }
1040    } else
1041      llvm_unreachable("Unknown reg class!");
1042    break;
1043  case 64:
1044    if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) {
1045      MachineInstrBuilder MIB =
1046      AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA))
1047                     .addFrameIndex(FI))
1048                     .addMemOperand(MMO);
1049      MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI);
1050      MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI);
1051      MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI);
1052      MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI);
1053      MIB = AddDReg(MIB, DestReg, ARM::dsub_4, RegState::DefineNoRead, TRI);
1054      MIB = AddDReg(MIB, DestReg, ARM::dsub_5, RegState::DefineNoRead, TRI);
1055      MIB = AddDReg(MIB, DestReg, ARM::dsub_6, RegState::DefineNoRead, TRI);
1056      MIB = AddDReg(MIB, DestReg, ARM::dsub_7, RegState::DefineNoRead, TRI);
1057      if (TargetRegisterInfo::isPhysicalRegister(DestReg))
1058        MIB.addReg(DestReg, RegState::ImplicitDefine);
1059    } else
1060      llvm_unreachable("Unknown reg class!");
1061    break;
1062  default:
1063    llvm_unreachable("Unknown regclass!");
1064  }
1065}
1066
1067unsigned
1068ARMBaseInstrInfo::isLoadFromStackSlot(const MachineInstr *MI,
1069                                      int &FrameIndex) const {
1070  switch (MI->getOpcode()) {
1071  default: break;
1072  case ARM::LDRrs:
1073  case ARM::t2LDRs:  // FIXME: don't use t2LDRs to access frame.
1074    if (MI->getOperand(1).isFI() &&
1075        MI->getOperand(2).isReg() &&
1076        MI->getOperand(3).isImm() &&
1077        MI->getOperand(2).getReg() == 0 &&
1078        MI->getOperand(3).getImm() == 0) {
1079      FrameIndex = MI->getOperand(1).getIndex();
1080      return MI->getOperand(0).getReg();
1081    }
1082    break;
1083  case ARM::LDRi12:
1084  case ARM::t2LDRi12:
1085  case ARM::tLDRspi:
1086  case ARM::VLDRD:
1087  case ARM::VLDRS:
1088    if (MI->getOperand(1).isFI() &&
1089        MI->getOperand(2).isImm() &&
1090        MI->getOperand(2).getImm() == 0) {
1091      FrameIndex = MI->getOperand(1).getIndex();
1092      return MI->getOperand(0).getReg();
1093    }
1094    break;
1095  case ARM::VLD1q64:
1096  case ARM::VLD1d64TPseudo:
1097  case ARM::VLD1d64QPseudo:
1098    if (MI->getOperand(1).isFI() &&
1099        MI->getOperand(0).getSubReg() == 0) {
1100      FrameIndex = MI->getOperand(1).getIndex();
1101      return MI->getOperand(0).getReg();
1102    }
1103    break;
1104  case ARM::VLDMQIA:
1105    if (MI->getOperand(1).isFI() &&
1106        MI->getOperand(0).getSubReg() == 0) {
1107      FrameIndex = MI->getOperand(1).getIndex();
1108      return MI->getOperand(0).getReg();
1109    }
1110    break;
1111  }
1112
1113  return 0;
1114}
1115
1116unsigned ARMBaseInstrInfo::isLoadFromStackSlotPostFE(const MachineInstr *MI,
1117                                             int &FrameIndex) const {
1118  const MachineMemOperand *Dummy;
1119  return MI->mayLoad() && hasLoadFromStackSlot(MI, Dummy, FrameIndex);
1120}
1121
1122bool ARMBaseInstrInfo::expandPostRAPseudo(MachineBasicBlock::iterator MI) const{
1123  // This hook gets to expand COPY instructions before they become
1124  // copyPhysReg() calls.  Look for VMOVS instructions that can legally be
1125  // widened to VMOVD.  We prefer the VMOVD when possible because it may be
1126  // changed into a VORR that can go down the NEON pipeline.
1127  if (!WidenVMOVS || !MI->isCopy())
1128    return false;
1129
1130  // Look for a copy between even S-registers.  That is where we keep floats
1131  // when using NEON v2f32 instructions for f32 arithmetic.
1132  unsigned DstRegS = MI->getOperand(0).getReg();
1133  unsigned SrcRegS = MI->getOperand(1).getReg();
1134  if (!ARM::SPRRegClass.contains(DstRegS, SrcRegS))
1135    return false;
1136
1137  const TargetRegisterInfo *TRI = &getRegisterInfo();
1138  unsigned DstRegD = TRI->getMatchingSuperReg(DstRegS, ARM::ssub_0,
1139                                              &ARM::DPRRegClass);
1140  unsigned SrcRegD = TRI->getMatchingSuperReg(SrcRegS, ARM::ssub_0,
1141                                              &ARM::DPRRegClass);
1142  if (!DstRegD || !SrcRegD)
1143    return false;
1144
1145  // We want to widen this into a DstRegD = VMOVD SrcRegD copy.  This is only
1146  // legal if the COPY already defines the full DstRegD, and it isn't a
1147  // sub-register insertion.
1148  if (!MI->definesRegister(DstRegD, TRI) || MI->readsRegister(DstRegD, TRI))
1149    return false;
1150
1151  // A dead copy shouldn't show up here, but reject it just in case.
1152  if (MI->getOperand(0).isDead())
1153    return false;
1154
1155  // All clear, widen the COPY.
1156  DEBUG(dbgs() << "widening:    " << *MI);
1157
1158  // Get rid of the old <imp-def> of DstRegD.  Leave it if it defines a Q-reg
1159  // or some other super-register.
1160  int ImpDefIdx = MI->findRegisterDefOperandIdx(DstRegD);
1161  if (ImpDefIdx != -1)
1162    MI->RemoveOperand(ImpDefIdx);
1163
1164  // Change the opcode and operands.
1165  MI->setDesc(get(ARM::VMOVD));
1166  MI->getOperand(0).setReg(DstRegD);
1167  MI->getOperand(1).setReg(SrcRegD);
1168  AddDefaultPred(MachineInstrBuilder(MI));
1169
1170  // We are now reading SrcRegD instead of SrcRegS.  This may upset the
1171  // register scavenger and machine verifier, so we need to indicate that we
1172  // are reading an undefined value from SrcRegD, but a proper value from
1173  // SrcRegS.
1174  MI->getOperand(1).setIsUndef();
1175  MachineInstrBuilder(MI).addReg(SrcRegS, RegState::Implicit);
1176
1177  // SrcRegD may actually contain an unrelated value in the ssub_1
1178  // sub-register.  Don't kill it.  Only kill the ssub_0 sub-register.
1179  if (MI->getOperand(1).isKill()) {
1180    MI->getOperand(1).setIsKill(false);
1181    MI->addRegisterKilled(SrcRegS, TRI, true);
1182  }
1183
1184  DEBUG(dbgs() << "replaced by: " << *MI);
1185  return true;
1186}
1187
1188MachineInstr*
1189ARMBaseInstrInfo::emitFrameIndexDebugValue(MachineFunction &MF,
1190                                           int FrameIx, uint64_t Offset,
1191                                           const MDNode *MDPtr,
1192                                           DebugLoc DL) const {
1193  MachineInstrBuilder MIB = BuildMI(MF, DL, get(ARM::DBG_VALUE))
1194    .addFrameIndex(FrameIx).addImm(0).addImm(Offset).addMetadata(MDPtr);
1195  return &*MIB;
1196}
1197
1198/// Create a copy of a const pool value. Update CPI to the new index and return
1199/// the label UID.
1200static unsigned duplicateCPV(MachineFunction &MF, unsigned &CPI) {
1201  MachineConstantPool *MCP = MF.getConstantPool();
1202  ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
1203
1204  const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPI];
1205  assert(MCPE.isMachineConstantPoolEntry() &&
1206         "Expecting a machine constantpool entry!");
1207  ARMConstantPoolValue *ACPV =
1208    static_cast<ARMConstantPoolValue*>(MCPE.Val.MachineCPVal);
1209
1210  unsigned PCLabelId = AFI->createPICLabelUId();
1211  ARMConstantPoolValue *NewCPV = 0;
1212  // FIXME: The below assumes PIC relocation model and that the function
1213  // is Thumb mode (t1 or t2). PCAdjustment would be 8 for ARM mode PIC, and
1214  // zero for non-PIC in ARM or Thumb. The callers are all of thumb LDR
1215  // instructions, so that's probably OK, but is PIC always correct when
1216  // we get here?
1217  if (ACPV->isGlobalValue())
1218    NewCPV = ARMConstantPoolConstant::
1219      Create(cast<ARMConstantPoolConstant>(ACPV)->getGV(), PCLabelId,
1220             ARMCP::CPValue, 4);
1221  else if (ACPV->isExtSymbol())
1222    NewCPV = ARMConstantPoolSymbol::
1223      Create(MF.getFunction()->getContext(),
1224             cast<ARMConstantPoolSymbol>(ACPV)->getSymbol(), PCLabelId, 4);
1225  else if (ACPV->isBlockAddress())
1226    NewCPV = ARMConstantPoolConstant::
1227      Create(cast<ARMConstantPoolConstant>(ACPV)->getBlockAddress(), PCLabelId,
1228             ARMCP::CPBlockAddress, 4);
1229  else if (ACPV->isLSDA())
1230    NewCPV = ARMConstantPoolConstant::Create(MF.getFunction(), PCLabelId,
1231                                             ARMCP::CPLSDA, 4);
1232  else if (ACPV->isMachineBasicBlock())
1233    NewCPV = ARMConstantPoolMBB::
1234      Create(MF.getFunction()->getContext(),
1235             cast<ARMConstantPoolMBB>(ACPV)->getMBB(), PCLabelId, 4);
1236  else
1237    llvm_unreachable("Unexpected ARM constantpool value type!!");
1238  CPI = MCP->getConstantPoolIndex(NewCPV, MCPE.getAlignment());
1239  return PCLabelId;
1240}
1241
1242void ARMBaseInstrInfo::
1243reMaterialize(MachineBasicBlock &MBB,
1244              MachineBasicBlock::iterator I,
1245              unsigned DestReg, unsigned SubIdx,
1246              const MachineInstr *Orig,
1247              const TargetRegisterInfo &TRI) const {
1248  unsigned Opcode = Orig->getOpcode();
1249  switch (Opcode) {
1250  default: {
1251    MachineInstr *MI = MBB.getParent()->CloneMachineInstr(Orig);
1252    MI->substituteRegister(Orig->getOperand(0).getReg(), DestReg, SubIdx, TRI);
1253    MBB.insert(I, MI);
1254    break;
1255  }
1256  case ARM::tLDRpci_pic:
1257  case ARM::t2LDRpci_pic: {
1258    MachineFunction &MF = *MBB.getParent();
1259    unsigned CPI = Orig->getOperand(1).getIndex();
1260    unsigned PCLabelId = duplicateCPV(MF, CPI);
1261    MachineInstrBuilder MIB = BuildMI(MBB, I, Orig->getDebugLoc(), get(Opcode),
1262                                      DestReg)
1263      .addConstantPoolIndex(CPI).addImm(PCLabelId);
1264    MIB->setMemRefs(Orig->memoperands_begin(), Orig->memoperands_end());
1265    break;
1266  }
1267  }
1268}
1269
1270MachineInstr *
1271ARMBaseInstrInfo::duplicate(MachineInstr *Orig, MachineFunction &MF) const {
1272  MachineInstr *MI = TargetInstrInfo::duplicate(Orig, MF);
1273  switch(Orig->getOpcode()) {
1274  case ARM::tLDRpci_pic:
1275  case ARM::t2LDRpci_pic: {
1276    unsigned CPI = Orig->getOperand(1).getIndex();
1277    unsigned PCLabelId = duplicateCPV(MF, CPI);
1278    Orig->getOperand(1).setIndex(CPI);
1279    Orig->getOperand(2).setImm(PCLabelId);
1280    break;
1281  }
1282  }
1283  return MI;
1284}
1285
1286bool ARMBaseInstrInfo::produceSameValue(const MachineInstr *MI0,
1287                                        const MachineInstr *MI1,
1288                                        const MachineRegisterInfo *MRI) const {
1289  int Opcode = MI0->getOpcode();
1290  if (Opcode == ARM::t2LDRpci ||
1291      Opcode == ARM::t2LDRpci_pic ||
1292      Opcode == ARM::tLDRpci ||
1293      Opcode == ARM::tLDRpci_pic ||
1294      Opcode == ARM::MOV_ga_dyn ||
1295      Opcode == ARM::MOV_ga_pcrel ||
1296      Opcode == ARM::MOV_ga_pcrel_ldr ||
1297      Opcode == ARM::t2MOV_ga_dyn ||
1298      Opcode == ARM::t2MOV_ga_pcrel) {
1299    if (MI1->getOpcode() != Opcode)
1300      return false;
1301    if (MI0->getNumOperands() != MI1->getNumOperands())
1302      return false;
1303
1304    const MachineOperand &MO0 = MI0->getOperand(1);
1305    const MachineOperand &MO1 = MI1->getOperand(1);
1306    if (MO0.getOffset() != MO1.getOffset())
1307      return false;
1308
1309    if (Opcode == ARM::MOV_ga_dyn ||
1310        Opcode == ARM::MOV_ga_pcrel ||
1311        Opcode == ARM::MOV_ga_pcrel_ldr ||
1312        Opcode == ARM::t2MOV_ga_dyn ||
1313        Opcode == ARM::t2MOV_ga_pcrel)
1314      // Ignore the PC labels.
1315      return MO0.getGlobal() == MO1.getGlobal();
1316
1317    const MachineFunction *MF = MI0->getParent()->getParent();
1318    const MachineConstantPool *MCP = MF->getConstantPool();
1319    int CPI0 = MO0.getIndex();
1320    int CPI1 = MO1.getIndex();
1321    const MachineConstantPoolEntry &MCPE0 = MCP->getConstants()[CPI0];
1322    const MachineConstantPoolEntry &MCPE1 = MCP->getConstants()[CPI1];
1323    bool isARMCP0 = MCPE0.isMachineConstantPoolEntry();
1324    bool isARMCP1 = MCPE1.isMachineConstantPoolEntry();
1325    if (isARMCP0 && isARMCP1) {
1326      ARMConstantPoolValue *ACPV0 =
1327        static_cast<ARMConstantPoolValue*>(MCPE0.Val.MachineCPVal);
1328      ARMConstantPoolValue *ACPV1 =
1329        static_cast<ARMConstantPoolValue*>(MCPE1.Val.MachineCPVal);
1330      return ACPV0->hasSameValue(ACPV1);
1331    } else if (!isARMCP0 && !isARMCP1) {
1332      return MCPE0.Val.ConstVal == MCPE1.Val.ConstVal;
1333    }
1334    return false;
1335  } else if (Opcode == ARM::PICLDR) {
1336    if (MI1->getOpcode() != Opcode)
1337      return false;
1338    if (MI0->getNumOperands() != MI1->getNumOperands())
1339      return false;
1340
1341    unsigned Addr0 = MI0->getOperand(1).getReg();
1342    unsigned Addr1 = MI1->getOperand(1).getReg();
1343    if (Addr0 != Addr1) {
1344      if (!MRI ||
1345          !TargetRegisterInfo::isVirtualRegister(Addr0) ||
1346          !TargetRegisterInfo::isVirtualRegister(Addr1))
1347        return false;
1348
1349      // This assumes SSA form.
1350      MachineInstr *Def0 = MRI->getVRegDef(Addr0);
1351      MachineInstr *Def1 = MRI->getVRegDef(Addr1);
1352      // Check if the loaded value, e.g. a constantpool of a global address, are
1353      // the same.
1354      if (!produceSameValue(Def0, Def1, MRI))
1355        return false;
1356    }
1357
1358    for (unsigned i = 3, e = MI0->getNumOperands(); i != e; ++i) {
1359      // %vreg12<def> = PICLDR %vreg11, 0, pred:14, pred:%noreg
1360      const MachineOperand &MO0 = MI0->getOperand(i);
1361      const MachineOperand &MO1 = MI1->getOperand(i);
1362      if (!MO0.isIdenticalTo(MO1))
1363        return false;
1364    }
1365    return true;
1366  }
1367
1368  return MI0->isIdenticalTo(MI1, MachineInstr::IgnoreVRegDefs);
1369}
1370
1371/// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler to
1372/// determine if two loads are loading from the same base address. It should
1373/// only return true if the base pointers are the same and the only differences
1374/// between the two addresses is the offset. It also returns the offsets by
1375/// reference.
1376///
1377/// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched
1378/// is permanently disabled.
1379bool ARMBaseInstrInfo::areLoadsFromSameBasePtr(SDNode *Load1, SDNode *Load2,
1380                                               int64_t &Offset1,
1381                                               int64_t &Offset2) const {
1382  // Don't worry about Thumb: just ARM and Thumb2.
1383  if (Subtarget.isThumb1Only()) return false;
1384
1385  if (!Load1->isMachineOpcode() || !Load2->isMachineOpcode())
1386    return false;
1387
1388  switch (Load1->getMachineOpcode()) {
1389  default:
1390    return false;
1391  case ARM::LDRi12:
1392  case ARM::LDRBi12:
1393  case ARM::LDRD:
1394  case ARM::LDRH:
1395  case ARM::LDRSB:
1396  case ARM::LDRSH:
1397  case ARM::VLDRD:
1398  case ARM::VLDRS:
1399  case ARM::t2LDRi8:
1400  case ARM::t2LDRDi8:
1401  case ARM::t2LDRSHi8:
1402  case ARM::t2LDRi12:
1403  case ARM::t2LDRSHi12:
1404    break;
1405  }
1406
1407  switch (Load2->getMachineOpcode()) {
1408  default:
1409    return false;
1410  case ARM::LDRi12:
1411  case ARM::LDRBi12:
1412  case ARM::LDRD:
1413  case ARM::LDRH:
1414  case ARM::LDRSB:
1415  case ARM::LDRSH:
1416  case ARM::VLDRD:
1417  case ARM::VLDRS:
1418  case ARM::t2LDRi8:
1419  case ARM::t2LDRSHi8:
1420  case ARM::t2LDRi12:
1421  case ARM::t2LDRSHi12:
1422    break;
1423  }
1424
1425  // Check if base addresses and chain operands match.
1426  if (Load1->getOperand(0) != Load2->getOperand(0) ||
1427      Load1->getOperand(4) != Load2->getOperand(4))
1428    return false;
1429
1430  // Index should be Reg0.
1431  if (Load1->getOperand(3) != Load2->getOperand(3))
1432    return false;
1433
1434  // Determine the offsets.
1435  if (isa<ConstantSDNode>(Load1->getOperand(1)) &&
1436      isa<ConstantSDNode>(Load2->getOperand(1))) {
1437    Offset1 = cast<ConstantSDNode>(Load1->getOperand(1))->getSExtValue();
1438    Offset2 = cast<ConstantSDNode>(Load2->getOperand(1))->getSExtValue();
1439    return true;
1440  }
1441
1442  return false;
1443}
1444
1445/// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to
1446/// determine (in conjunction with areLoadsFromSameBasePtr) if two loads should
1447/// be scheduled togther. On some targets if two loads are loading from
1448/// addresses in the same cache line, it's better if they are scheduled
1449/// together. This function takes two integers that represent the load offsets
1450/// from the common base address. It returns true if it decides it's desirable
1451/// to schedule the two loads together. "NumLoads" is the number of loads that
1452/// have already been scheduled after Load1.
1453///
1454/// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched
1455/// is permanently disabled.
1456bool ARMBaseInstrInfo::shouldScheduleLoadsNear(SDNode *Load1, SDNode *Load2,
1457                                               int64_t Offset1, int64_t Offset2,
1458                                               unsigned NumLoads) const {
1459  // Don't worry about Thumb: just ARM and Thumb2.
1460  if (Subtarget.isThumb1Only()) return false;
1461
1462  assert(Offset2 > Offset1);
1463
1464  if ((Offset2 - Offset1) / 8 > 64)
1465    return false;
1466
1467  if (Load1->getMachineOpcode() != Load2->getMachineOpcode())
1468    return false;  // FIXME: overly conservative?
1469
1470  // Four loads in a row should be sufficient.
1471  if (NumLoads >= 3)
1472    return false;
1473
1474  return true;
1475}
1476
1477bool ARMBaseInstrInfo::isSchedulingBoundary(const MachineInstr *MI,
1478                                            const MachineBasicBlock *MBB,
1479                                            const MachineFunction &MF) const {
1480  // Debug info is never a scheduling boundary. It's necessary to be explicit
1481  // due to the special treatment of IT instructions below, otherwise a
1482  // dbg_value followed by an IT will result in the IT instruction being
1483  // considered a scheduling hazard, which is wrong. It should be the actual
1484  // instruction preceding the dbg_value instruction(s), just like it is
1485  // when debug info is not present.
1486  if (MI->isDebugValue())
1487    return false;
1488
1489  // Terminators and labels can't be scheduled around.
1490  if (MI->isTerminator() || MI->isLabel())
1491    return true;
1492
1493  // Treat the start of the IT block as a scheduling boundary, but schedule
1494  // t2IT along with all instructions following it.
1495  // FIXME: This is a big hammer. But the alternative is to add all potential
1496  // true and anti dependencies to IT block instructions as implicit operands
1497  // to the t2IT instruction. The added compile time and complexity does not
1498  // seem worth it.
1499  MachineBasicBlock::const_iterator I = MI;
1500  // Make sure to skip any dbg_value instructions
1501  while (++I != MBB->end() && I->isDebugValue())
1502    ;
1503  if (I != MBB->end() && I->getOpcode() == ARM::t2IT)
1504    return true;
1505
1506  // Don't attempt to schedule around any instruction that defines
1507  // a stack-oriented pointer, as it's unlikely to be profitable. This
1508  // saves compile time, because it doesn't require every single
1509  // stack slot reference to depend on the instruction that does the
1510  // modification.
1511  // Calls don't actually change the stack pointer, even if they have imp-defs.
1512  // No ARM calling conventions change the stack pointer. (X86 calling
1513  // conventions sometimes do).
1514  if (!MI->isCall() && MI->definesRegister(ARM::SP))
1515    return true;
1516
1517  return false;
1518}
1519
1520bool ARMBaseInstrInfo::
1521isProfitableToIfCvt(MachineBasicBlock &MBB,
1522                    unsigned NumCycles, unsigned ExtraPredCycles,
1523                    const BranchProbability &Probability) const {
1524  if (!NumCycles)
1525    return false;
1526
1527  // Attempt to estimate the relative costs of predication versus branching.
1528  unsigned UnpredCost = Probability.getNumerator() * NumCycles;
1529  UnpredCost /= Probability.getDenominator();
1530  UnpredCost += 1; // The branch itself
1531  UnpredCost += Subtarget.getMispredictionPenalty() / 10;
1532
1533  return (NumCycles + ExtraPredCycles) <= UnpredCost;
1534}
1535
1536bool ARMBaseInstrInfo::
1537isProfitableToIfCvt(MachineBasicBlock &TMBB,
1538                    unsigned TCycles, unsigned TExtra,
1539                    MachineBasicBlock &FMBB,
1540                    unsigned FCycles, unsigned FExtra,
1541                    const BranchProbability &Probability) const {
1542  if (!TCycles || !FCycles)
1543    return false;
1544
1545  // Attempt to estimate the relative costs of predication versus branching.
1546  unsigned TUnpredCost = Probability.getNumerator() * TCycles;
1547  TUnpredCost /= Probability.getDenominator();
1548
1549  uint32_t Comp = Probability.getDenominator() - Probability.getNumerator();
1550  unsigned FUnpredCost = Comp * FCycles;
1551  FUnpredCost /= Probability.getDenominator();
1552
1553  unsigned UnpredCost = TUnpredCost + FUnpredCost;
1554  UnpredCost += 1; // The branch itself
1555  UnpredCost += Subtarget.getMispredictionPenalty() / 10;
1556
1557  return (TCycles + FCycles + TExtra + FExtra) <= UnpredCost;
1558}
1559
1560bool
1561ARMBaseInstrInfo::isProfitableToUnpredicate(MachineBasicBlock &TMBB,
1562                                            MachineBasicBlock &FMBB) const {
1563  // Reduce false anti-dependencies to let Swift's out-of-order execution
1564  // engine do its thing.
1565  return Subtarget.isSwift();
1566}
1567
1568/// getInstrPredicate - If instruction is predicated, returns its predicate
1569/// condition, otherwise returns AL. It also returns the condition code
1570/// register by reference.
1571ARMCC::CondCodes
1572llvm::getInstrPredicate(const MachineInstr *MI, unsigned &PredReg) {
1573  int PIdx = MI->findFirstPredOperandIdx();
1574  if (PIdx == -1) {
1575    PredReg = 0;
1576    return ARMCC::AL;
1577  }
1578
1579  PredReg = MI->getOperand(PIdx+1).getReg();
1580  return (ARMCC::CondCodes)MI->getOperand(PIdx).getImm();
1581}
1582
1583
1584int llvm::getMatchingCondBranchOpcode(int Opc) {
1585  if (Opc == ARM::B)
1586    return ARM::Bcc;
1587  if (Opc == ARM::tB)
1588    return ARM::tBcc;
1589  if (Opc == ARM::t2B)
1590    return ARM::t2Bcc;
1591
1592  llvm_unreachable("Unknown unconditional branch opcode!");
1593}
1594
1595/// commuteInstruction - Handle commutable instructions.
1596MachineInstr *
1597ARMBaseInstrInfo::commuteInstruction(MachineInstr *MI, bool NewMI) const {
1598  switch (MI->getOpcode()) {
1599  case ARM::MOVCCr:
1600  case ARM::t2MOVCCr: {
1601    // MOVCC can be commuted by inverting the condition.
1602    unsigned PredReg = 0;
1603    ARMCC::CondCodes CC = getInstrPredicate(MI, PredReg);
1604    // MOVCC AL can't be inverted. Shouldn't happen.
1605    if (CC == ARMCC::AL || PredReg != ARM::CPSR)
1606      return NULL;
1607    MI = TargetInstrInfo::commuteInstruction(MI, NewMI);
1608    if (!MI)
1609      return NULL;
1610    // After swapping the MOVCC operands, also invert the condition.
1611    MI->getOperand(MI->findFirstPredOperandIdx())
1612      .setImm(ARMCC::getOppositeCondition(CC));
1613    return MI;
1614  }
1615  }
1616  return TargetInstrInfo::commuteInstruction(MI, NewMI);
1617}
1618
1619/// Identify instructions that can be folded into a MOVCC instruction, and
1620/// return the defining instruction.
1621static MachineInstr *canFoldIntoMOVCC(unsigned Reg,
1622                                      const MachineRegisterInfo &MRI,
1623                                      const TargetInstrInfo *TII) {
1624  if (!TargetRegisterInfo::isVirtualRegister(Reg))
1625    return 0;
1626  if (!MRI.hasOneNonDBGUse(Reg))
1627    return 0;
1628  MachineInstr *MI = MRI.getVRegDef(Reg);
1629  if (!MI)
1630    return 0;
1631  // MI is folded into the MOVCC by predicating it.
1632  if (!MI->isPredicable())
1633    return 0;
1634  // Check if MI has any non-dead defs or physreg uses. This also detects
1635  // predicated instructions which will be reading CPSR.
1636  for (unsigned i = 1, e = MI->getNumOperands(); i != e; ++i) {
1637    const MachineOperand &MO = MI->getOperand(i);
1638    // Reject frame index operands, PEI can't handle the predicated pseudos.
1639    if (MO.isFI() || MO.isCPI() || MO.isJTI())
1640      return 0;
1641    if (!MO.isReg())
1642      continue;
1643    // MI can't have any tied operands, that would conflict with predication.
1644    if (MO.isTied())
1645      return 0;
1646    if (TargetRegisterInfo::isPhysicalRegister(MO.getReg()))
1647      return 0;
1648    if (MO.isDef() && !MO.isDead())
1649      return 0;
1650  }
1651  bool DontMoveAcrossStores = true;
1652  if (!MI->isSafeToMove(TII, /* AliasAnalysis = */ 0, DontMoveAcrossStores))
1653    return 0;
1654  return MI;
1655}
1656
1657bool ARMBaseInstrInfo::analyzeSelect(const MachineInstr *MI,
1658                                     SmallVectorImpl<MachineOperand> &Cond,
1659                                     unsigned &TrueOp, unsigned &FalseOp,
1660                                     bool &Optimizable) const {
1661  assert((MI->getOpcode() == ARM::MOVCCr || MI->getOpcode() == ARM::t2MOVCCr) &&
1662         "Unknown select instruction");
1663  // MOVCC operands:
1664  // 0: Def.
1665  // 1: True use.
1666  // 2: False use.
1667  // 3: Condition code.
1668  // 4: CPSR use.
1669  TrueOp = 1;
1670  FalseOp = 2;
1671  Cond.push_back(MI->getOperand(3));
1672  Cond.push_back(MI->getOperand(4));
1673  // We can always fold a def.
1674  Optimizable = true;
1675  return false;
1676}
1677
1678MachineInstr *ARMBaseInstrInfo::optimizeSelect(MachineInstr *MI,
1679                                               bool PreferFalse) const {
1680  assert((MI->getOpcode() == ARM::MOVCCr || MI->getOpcode() == ARM::t2MOVCCr) &&
1681         "Unknown select instruction");
1682  const MachineRegisterInfo &MRI = MI->getParent()->getParent()->getRegInfo();
1683  MachineInstr *DefMI = canFoldIntoMOVCC(MI->getOperand(2).getReg(), MRI, this);
1684  bool Invert = !DefMI;
1685  if (!DefMI)
1686    DefMI = canFoldIntoMOVCC(MI->getOperand(1).getReg(), MRI, this);
1687  if (!DefMI)
1688    return 0;
1689
1690  // Create a new predicated version of DefMI.
1691  // Rfalse is the first use.
1692  MachineInstrBuilder NewMI = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(),
1693                                      DefMI->getDesc(),
1694                                      MI->getOperand(0).getReg());
1695
1696  // Copy all the DefMI operands, excluding its (null) predicate.
1697  const MCInstrDesc &DefDesc = DefMI->getDesc();
1698  for (unsigned i = 1, e = DefDesc.getNumOperands();
1699       i != e && !DefDesc.OpInfo[i].isPredicate(); ++i)
1700    NewMI.addOperand(DefMI->getOperand(i));
1701
1702  unsigned CondCode = MI->getOperand(3).getImm();
1703  if (Invert)
1704    NewMI.addImm(ARMCC::getOppositeCondition(ARMCC::CondCodes(CondCode)));
1705  else
1706    NewMI.addImm(CondCode);
1707  NewMI.addOperand(MI->getOperand(4));
1708
1709  // DefMI is not the -S version that sets CPSR, so add an optional %noreg.
1710  if (NewMI->hasOptionalDef())
1711    AddDefaultCC(NewMI);
1712
1713  // The output register value when the predicate is false is an implicit
1714  // register operand tied to the first def.
1715  // The tie makes the register allocator ensure the FalseReg is allocated the
1716  // same register as operand 0.
1717  MachineOperand FalseReg = MI->getOperand(Invert ? 2 : 1);
1718  FalseReg.setImplicit();
1719  NewMI->addOperand(FalseReg);
1720  NewMI->tieOperands(0, NewMI->getNumOperands() - 1);
1721
1722  // The caller will erase MI, but not DefMI.
1723  DefMI->eraseFromParent();
1724  return NewMI;
1725}
1726
1727/// Map pseudo instructions that imply an 'S' bit onto real opcodes. Whether the
1728/// instruction is encoded with an 'S' bit is determined by the optional CPSR
1729/// def operand.
1730///
1731/// This will go away once we can teach tblgen how to set the optional CPSR def
1732/// operand itself.
1733struct AddSubFlagsOpcodePair {
1734  uint16_t PseudoOpc;
1735  uint16_t MachineOpc;
1736};
1737
1738static const AddSubFlagsOpcodePair AddSubFlagsOpcodeMap[] = {
1739  {ARM::ADDSri, ARM::ADDri},
1740  {ARM::ADDSrr, ARM::ADDrr},
1741  {ARM::ADDSrsi, ARM::ADDrsi},
1742  {ARM::ADDSrsr, ARM::ADDrsr},
1743
1744  {ARM::SUBSri, ARM::SUBri},
1745  {ARM::SUBSrr, ARM::SUBrr},
1746  {ARM::SUBSrsi, ARM::SUBrsi},
1747  {ARM::SUBSrsr, ARM::SUBrsr},
1748
1749  {ARM::RSBSri, ARM::RSBri},
1750  {ARM::RSBSrsi, ARM::RSBrsi},
1751  {ARM::RSBSrsr, ARM::RSBrsr},
1752
1753  {ARM::t2ADDSri, ARM::t2ADDri},
1754  {ARM::t2ADDSrr, ARM::t2ADDrr},
1755  {ARM::t2ADDSrs, ARM::t2ADDrs},
1756
1757  {ARM::t2SUBSri, ARM::t2SUBri},
1758  {ARM::t2SUBSrr, ARM::t2SUBrr},
1759  {ARM::t2SUBSrs, ARM::t2SUBrs},
1760
1761  {ARM::t2RSBSri, ARM::t2RSBri},
1762  {ARM::t2RSBSrs, ARM::t2RSBrs},
1763};
1764
1765unsigned llvm::convertAddSubFlagsOpcode(unsigned OldOpc) {
1766  for (unsigned i = 0, e = array_lengthof(AddSubFlagsOpcodeMap); i != e; ++i)
1767    if (OldOpc == AddSubFlagsOpcodeMap[i].PseudoOpc)
1768      return AddSubFlagsOpcodeMap[i].MachineOpc;
1769  return 0;
1770}
1771
1772void llvm::emitARMRegPlusImmediate(MachineBasicBlock &MBB,
1773                               MachineBasicBlock::iterator &MBBI, DebugLoc dl,
1774                               unsigned DestReg, unsigned BaseReg, int NumBytes,
1775                               ARMCC::CondCodes Pred, unsigned PredReg,
1776                               const ARMBaseInstrInfo &TII, unsigned MIFlags) {
1777  bool isSub = NumBytes < 0;
1778  if (isSub) NumBytes = -NumBytes;
1779
1780  while (NumBytes) {
1781    unsigned RotAmt = ARM_AM::getSOImmValRotate(NumBytes);
1782    unsigned ThisVal = NumBytes & ARM_AM::rotr32(0xFF, RotAmt);
1783    assert(ThisVal && "Didn't extract field correctly");
1784
1785    // We will handle these bits from offset, clear them.
1786    NumBytes &= ~ThisVal;
1787
1788    assert(ARM_AM::getSOImmVal(ThisVal) != -1 && "Bit extraction didn't work?");
1789
1790    // Build the new ADD / SUB.
1791    unsigned Opc = isSub ? ARM::SUBri : ARM::ADDri;
1792    BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
1793      .addReg(BaseReg, RegState::Kill).addImm(ThisVal)
1794      .addImm((unsigned)Pred).addReg(PredReg).addReg(0)
1795      .setMIFlags(MIFlags);
1796    BaseReg = DestReg;
1797  }
1798}
1799
1800bool llvm::rewriteARMFrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
1801                                unsigned FrameReg, int &Offset,
1802                                const ARMBaseInstrInfo &TII) {
1803  unsigned Opcode = MI.getOpcode();
1804  const MCInstrDesc &Desc = MI.getDesc();
1805  unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
1806  bool isSub = false;
1807
1808  // Memory operands in inline assembly always use AddrMode2.
1809  if (Opcode == ARM::INLINEASM)
1810    AddrMode = ARMII::AddrMode2;
1811
1812  if (Opcode == ARM::ADDri) {
1813    Offset += MI.getOperand(FrameRegIdx+1).getImm();
1814    if (Offset == 0) {
1815      // Turn it into a move.
1816      MI.setDesc(TII.get(ARM::MOVr));
1817      MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
1818      MI.RemoveOperand(FrameRegIdx+1);
1819      Offset = 0;
1820      return true;
1821    } else if (Offset < 0) {
1822      Offset = -Offset;
1823      isSub = true;
1824      MI.setDesc(TII.get(ARM::SUBri));
1825    }
1826
1827    // Common case: small offset, fits into instruction.
1828    if (ARM_AM::getSOImmVal(Offset) != -1) {
1829      // Replace the FrameIndex with sp / fp
1830      MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
1831      MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
1832      Offset = 0;
1833      return true;
1834    }
1835
1836    // Otherwise, pull as much of the immedidate into this ADDri/SUBri
1837    // as possible.
1838    unsigned RotAmt = ARM_AM::getSOImmValRotate(Offset);
1839    unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xFF, RotAmt);
1840
1841    // We will handle these bits from offset, clear them.
1842    Offset &= ~ThisImmVal;
1843
1844    // Get the properly encoded SOImmVal field.
1845    assert(ARM_AM::getSOImmVal(ThisImmVal) != -1 &&
1846           "Bit extraction didn't work?");
1847    MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal);
1848 } else {
1849    unsigned ImmIdx = 0;
1850    int InstrOffs = 0;
1851    unsigned NumBits = 0;
1852    unsigned Scale = 1;
1853    switch (AddrMode) {
1854    case ARMII::AddrMode_i12: {
1855      ImmIdx = FrameRegIdx + 1;
1856      InstrOffs = MI.getOperand(ImmIdx).getImm();
1857      NumBits = 12;
1858      break;
1859    }
1860    case ARMII::AddrMode2: {
1861      ImmIdx = FrameRegIdx+2;
1862      InstrOffs = ARM_AM::getAM2Offset(MI.getOperand(ImmIdx).getImm());
1863      if (ARM_AM::getAM2Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub)
1864        InstrOffs *= -1;
1865      NumBits = 12;
1866      break;
1867    }
1868    case ARMII::AddrMode3: {
1869      ImmIdx = FrameRegIdx+2;
1870      InstrOffs = ARM_AM::getAM3Offset(MI.getOperand(ImmIdx).getImm());
1871      if (ARM_AM::getAM3Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub)
1872        InstrOffs *= -1;
1873      NumBits = 8;
1874      break;
1875    }
1876    case ARMII::AddrMode4:
1877    case ARMII::AddrMode6:
1878      // Can't fold any offset even if it's zero.
1879      return false;
1880    case ARMII::AddrMode5: {
1881      ImmIdx = FrameRegIdx+1;
1882      InstrOffs = ARM_AM::getAM5Offset(MI.getOperand(ImmIdx).getImm());
1883      if (ARM_AM::getAM5Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub)
1884        InstrOffs *= -1;
1885      NumBits = 8;
1886      Scale = 4;
1887      break;
1888    }
1889    default:
1890      llvm_unreachable("Unsupported addressing mode!");
1891    }
1892
1893    Offset += InstrOffs * Scale;
1894    assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!");
1895    if (Offset < 0) {
1896      Offset = -Offset;
1897      isSub = true;
1898    }
1899
1900    // Attempt to fold address comp. if opcode has offset bits
1901    if (NumBits > 0) {
1902      // Common case: small offset, fits into instruction.
1903      MachineOperand &ImmOp = MI.getOperand(ImmIdx);
1904      int ImmedOffset = Offset / Scale;
1905      unsigned Mask = (1 << NumBits) - 1;
1906      if ((unsigned)Offset <= Mask * Scale) {
1907        // Replace the FrameIndex with sp
1908        MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
1909        // FIXME: When addrmode2 goes away, this will simplify (like the
1910        // T2 version), as the LDR.i12 versions don't need the encoding
1911        // tricks for the offset value.
1912        if (isSub) {
1913          if (AddrMode == ARMII::AddrMode_i12)
1914            ImmedOffset = -ImmedOffset;
1915          else
1916            ImmedOffset |= 1 << NumBits;
1917        }
1918        ImmOp.ChangeToImmediate(ImmedOffset);
1919        Offset = 0;
1920        return true;
1921      }
1922
1923      // Otherwise, it didn't fit. Pull in what we can to simplify the immed.
1924      ImmedOffset = ImmedOffset & Mask;
1925      if (isSub) {
1926        if (AddrMode == ARMII::AddrMode_i12)
1927          ImmedOffset = -ImmedOffset;
1928        else
1929          ImmedOffset |= 1 << NumBits;
1930      }
1931      ImmOp.ChangeToImmediate(ImmedOffset);
1932      Offset &= ~(Mask*Scale);
1933    }
1934  }
1935
1936  Offset = (isSub) ? -Offset : Offset;
1937  return Offset == 0;
1938}
1939
1940/// analyzeCompare - For a comparison instruction, return the source registers
1941/// in SrcReg and SrcReg2 if having two register operands, and the value it
1942/// compares against in CmpValue. Return true if the comparison instruction
1943/// can be analyzed.
1944bool ARMBaseInstrInfo::
1945analyzeCompare(const MachineInstr *MI, unsigned &SrcReg, unsigned &SrcReg2,
1946               int &CmpMask, int &CmpValue) const {
1947  switch (MI->getOpcode()) {
1948  default: break;
1949  case ARM::CMPri:
1950  case ARM::t2CMPri:
1951    SrcReg = MI->getOperand(0).getReg();
1952    SrcReg2 = 0;
1953    CmpMask = ~0;
1954    CmpValue = MI->getOperand(1).getImm();
1955    return true;
1956  case ARM::CMPrr:
1957  case ARM::t2CMPrr:
1958    SrcReg = MI->getOperand(0).getReg();
1959    SrcReg2 = MI->getOperand(1).getReg();
1960    CmpMask = ~0;
1961    CmpValue = 0;
1962    return true;
1963  case ARM::TSTri:
1964  case ARM::t2TSTri:
1965    SrcReg = MI->getOperand(0).getReg();
1966    SrcReg2 = 0;
1967    CmpMask = MI->getOperand(1).getImm();
1968    CmpValue = 0;
1969    return true;
1970  }
1971
1972  return false;
1973}
1974
1975/// isSuitableForMask - Identify a suitable 'and' instruction that
1976/// operates on the given source register and applies the same mask
1977/// as a 'tst' instruction. Provide a limited look-through for copies.
1978/// When successful, MI will hold the found instruction.
1979static bool isSuitableForMask(MachineInstr *&MI, unsigned SrcReg,
1980                              int CmpMask, bool CommonUse) {
1981  switch (MI->getOpcode()) {
1982    case ARM::ANDri:
1983    case ARM::t2ANDri:
1984      if (CmpMask != MI->getOperand(2).getImm())
1985        return false;
1986      if (SrcReg == MI->getOperand(CommonUse ? 1 : 0).getReg())
1987        return true;
1988      break;
1989    case ARM::COPY: {
1990      // Walk down one instruction which is potentially an 'and'.
1991      const MachineInstr &Copy = *MI;
1992      MachineBasicBlock::iterator AND(
1993        llvm::next(MachineBasicBlock::iterator(MI)));
1994      if (AND == MI->getParent()->end()) return false;
1995      MI = AND;
1996      return isSuitableForMask(MI, Copy.getOperand(0).getReg(),
1997                               CmpMask, true);
1998    }
1999  }
2000
2001  return false;
2002}
2003
2004/// getSwappedCondition - assume the flags are set by MI(a,b), return
2005/// the condition code if we modify the instructions such that flags are
2006/// set by MI(b,a).
2007inline static ARMCC::CondCodes getSwappedCondition(ARMCC::CondCodes CC) {
2008  switch (CC) {
2009  default: return ARMCC::AL;
2010  case ARMCC::EQ: return ARMCC::EQ;
2011  case ARMCC::NE: return ARMCC::NE;
2012  case ARMCC::HS: return ARMCC::LS;
2013  case ARMCC::LO: return ARMCC::HI;
2014  case ARMCC::HI: return ARMCC::LO;
2015  case ARMCC::LS: return ARMCC::HS;
2016  case ARMCC::GE: return ARMCC::LE;
2017  case ARMCC::LT: return ARMCC::GT;
2018  case ARMCC::GT: return ARMCC::LT;
2019  case ARMCC::LE: return ARMCC::GE;
2020  }
2021}
2022
2023/// isRedundantFlagInstr - check whether the first instruction, whose only
2024/// purpose is to update flags, can be made redundant.
2025/// CMPrr can be made redundant by SUBrr if the operands are the same.
2026/// CMPri can be made redundant by SUBri if the operands are the same.
2027/// This function can be extended later on.
2028inline static bool isRedundantFlagInstr(MachineInstr *CmpI, unsigned SrcReg,
2029                                        unsigned SrcReg2, int ImmValue,
2030                                        MachineInstr *OI) {
2031  if ((CmpI->getOpcode() == ARM::CMPrr ||
2032       CmpI->getOpcode() == ARM::t2CMPrr) &&
2033      (OI->getOpcode() == ARM::SUBrr ||
2034       OI->getOpcode() == ARM::t2SUBrr) &&
2035      ((OI->getOperand(1).getReg() == SrcReg &&
2036        OI->getOperand(2).getReg() == SrcReg2) ||
2037       (OI->getOperand(1).getReg() == SrcReg2 &&
2038        OI->getOperand(2).getReg() == SrcReg)))
2039    return true;
2040
2041  if ((CmpI->getOpcode() == ARM::CMPri ||
2042       CmpI->getOpcode() == ARM::t2CMPri) &&
2043      (OI->getOpcode() == ARM::SUBri ||
2044       OI->getOpcode() == ARM::t2SUBri) &&
2045      OI->getOperand(1).getReg() == SrcReg &&
2046      OI->getOperand(2).getImm() == ImmValue)
2047    return true;
2048  return false;
2049}
2050
2051/// optimizeCompareInstr - Convert the instruction supplying the argument to the
2052/// comparison into one that sets the zero bit in the flags register;
2053/// Remove a redundant Compare instruction if an earlier instruction can set the
2054/// flags in the same way as Compare.
2055/// E.g. SUBrr(r1,r2) and CMPrr(r1,r2). We also handle the case where two
2056/// operands are swapped: SUBrr(r1,r2) and CMPrr(r2,r1), by updating the
2057/// condition code of instructions which use the flags.
2058bool ARMBaseInstrInfo::
2059optimizeCompareInstr(MachineInstr *CmpInstr, unsigned SrcReg, unsigned SrcReg2,
2060                     int CmpMask, int CmpValue,
2061                     const MachineRegisterInfo *MRI) const {
2062  // Get the unique definition of SrcReg.
2063  MachineInstr *MI = MRI->getUniqueVRegDef(SrcReg);
2064  if (!MI) return false;
2065
2066  // Masked compares sometimes use the same register as the corresponding 'and'.
2067  if (CmpMask != ~0) {
2068    if (!isSuitableForMask(MI, SrcReg, CmpMask, false) || isPredicated(MI)) {
2069      MI = 0;
2070      for (MachineRegisterInfo::use_iterator UI = MRI->use_begin(SrcReg),
2071           UE = MRI->use_end(); UI != UE; ++UI) {
2072        if (UI->getParent() != CmpInstr->getParent()) continue;
2073        MachineInstr *PotentialAND = &*UI;
2074        if (!isSuitableForMask(PotentialAND, SrcReg, CmpMask, true) ||
2075            isPredicated(PotentialAND))
2076          continue;
2077        MI = PotentialAND;
2078        break;
2079      }
2080      if (!MI) return false;
2081    }
2082  }
2083
2084  // Get ready to iterate backward from CmpInstr.
2085  MachineBasicBlock::iterator I = CmpInstr, E = MI,
2086                              B = CmpInstr->getParent()->begin();
2087
2088  // Early exit if CmpInstr is at the beginning of the BB.
2089  if (I == B) return false;
2090
2091  // There are two possible candidates which can be changed to set CPSR:
2092  // One is MI, the other is a SUB instruction.
2093  // For CMPrr(r1,r2), we are looking for SUB(r1,r2) or SUB(r2,r1).
2094  // For CMPri(r1, CmpValue), we are looking for SUBri(r1, CmpValue).
2095  MachineInstr *Sub = NULL;
2096  if (SrcReg2 != 0)
2097    // MI is not a candidate for CMPrr.
2098    MI = NULL;
2099  else if (MI->getParent() != CmpInstr->getParent() || CmpValue != 0) {
2100    // Conservatively refuse to convert an instruction which isn't in the same
2101    // BB as the comparison.
2102    // For CMPri, we need to check Sub, thus we can't return here.
2103    if (CmpInstr->getOpcode() == ARM::CMPri ||
2104       CmpInstr->getOpcode() == ARM::t2CMPri)
2105      MI = NULL;
2106    else
2107      return false;
2108  }
2109
2110  // Check that CPSR isn't set between the comparison instruction and the one we
2111  // want to change. At the same time, search for Sub.
2112  const TargetRegisterInfo *TRI = &getRegisterInfo();
2113  --I;
2114  for (; I != E; --I) {
2115    const MachineInstr &Instr = *I;
2116
2117    if (Instr.modifiesRegister(ARM::CPSR, TRI) ||
2118        Instr.readsRegister(ARM::CPSR, TRI))
2119      // This instruction modifies or uses CPSR after the one we want to
2120      // change. We can't do this transformation.
2121      return false;
2122
2123    // Check whether CmpInstr can be made redundant by the current instruction.
2124    if (isRedundantFlagInstr(CmpInstr, SrcReg, SrcReg2, CmpValue, &*I)) {
2125      Sub = &*I;
2126      break;
2127    }
2128
2129    if (I == B)
2130      // The 'and' is below the comparison instruction.
2131      return false;
2132  }
2133
2134  // Return false if no candidates exist.
2135  if (!MI && !Sub)
2136    return false;
2137
2138  // The single candidate is called MI.
2139  if (!MI) MI = Sub;
2140
2141  // We can't use a predicated instruction - it doesn't always write the flags.
2142  if (isPredicated(MI))
2143    return false;
2144
2145  switch (MI->getOpcode()) {
2146  default: break;
2147  case ARM::RSBrr:
2148  case ARM::RSBri:
2149  case ARM::RSCrr:
2150  case ARM::RSCri:
2151  case ARM::ADDrr:
2152  case ARM::ADDri:
2153  case ARM::ADCrr:
2154  case ARM::ADCri:
2155  case ARM::SUBrr:
2156  case ARM::SUBri:
2157  case ARM::SBCrr:
2158  case ARM::SBCri:
2159  case ARM::t2RSBri:
2160  case ARM::t2ADDrr:
2161  case ARM::t2ADDri:
2162  case ARM::t2ADCrr:
2163  case ARM::t2ADCri:
2164  case ARM::t2SUBrr:
2165  case ARM::t2SUBri:
2166  case ARM::t2SBCrr:
2167  case ARM::t2SBCri:
2168  case ARM::ANDrr:
2169  case ARM::ANDri:
2170  case ARM::t2ANDrr:
2171  case ARM::t2ANDri:
2172  case ARM::ORRrr:
2173  case ARM::ORRri:
2174  case ARM::t2ORRrr:
2175  case ARM::t2ORRri:
2176  case ARM::EORrr:
2177  case ARM::EORri:
2178  case ARM::t2EORrr:
2179  case ARM::t2EORri: {
2180    // Scan forward for the use of CPSR
2181    // When checking against MI: if it's a conditional code requires
2182    // checking of V bit, then this is not safe to do.
2183    // It is safe to remove CmpInstr if CPSR is redefined or killed.
2184    // If we are done with the basic block, we need to check whether CPSR is
2185    // live-out.
2186    SmallVector<std::pair<MachineOperand*, ARMCC::CondCodes>, 4>
2187        OperandsToUpdate;
2188    bool isSafe = false;
2189    I = CmpInstr;
2190    E = CmpInstr->getParent()->end();
2191    while (!isSafe && ++I != E) {
2192      const MachineInstr &Instr = *I;
2193      for (unsigned IO = 0, EO = Instr.getNumOperands();
2194           !isSafe && IO != EO; ++IO) {
2195        const MachineOperand &MO = Instr.getOperand(IO);
2196        if (MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) {
2197          isSafe = true;
2198          break;
2199        }
2200        if (!MO.isReg() || MO.getReg() != ARM::CPSR)
2201          continue;
2202        if (MO.isDef()) {
2203          isSafe = true;
2204          break;
2205        }
2206        // Condition code is after the operand before CPSR.
2207        ARMCC::CondCodes CC = (ARMCC::CondCodes)Instr.getOperand(IO-1).getImm();
2208        if (Sub) {
2209          ARMCC::CondCodes NewCC = getSwappedCondition(CC);
2210          if (NewCC == ARMCC::AL)
2211            return false;
2212          // If we have SUB(r1, r2) and CMP(r2, r1), the condition code based
2213          // on CMP needs to be updated to be based on SUB.
2214          // Push the condition code operands to OperandsToUpdate.
2215          // If it is safe to remove CmpInstr, the condition code of these
2216          // operands will be modified.
2217          if (SrcReg2 != 0 && Sub->getOperand(1).getReg() == SrcReg2 &&
2218              Sub->getOperand(2).getReg() == SrcReg)
2219            OperandsToUpdate.push_back(std::make_pair(&((*I).getOperand(IO-1)),
2220                                                      NewCC));
2221        }
2222        else
2223          switch (CC) {
2224          default:
2225            // CPSR can be used multiple times, we should continue.
2226            break;
2227          case ARMCC::VS:
2228          case ARMCC::VC:
2229          case ARMCC::GE:
2230          case ARMCC::LT:
2231          case ARMCC::GT:
2232          case ARMCC::LE:
2233            return false;
2234          }
2235      }
2236    }
2237
2238    // If CPSR is not killed nor re-defined, we should check whether it is
2239    // live-out. If it is live-out, do not optimize.
2240    if (!isSafe) {
2241      MachineBasicBlock *MBB = CmpInstr->getParent();
2242      for (MachineBasicBlock::succ_iterator SI = MBB->succ_begin(),
2243               SE = MBB->succ_end(); SI != SE; ++SI)
2244        if ((*SI)->isLiveIn(ARM::CPSR))
2245          return false;
2246    }
2247
2248    // Toggle the optional operand to CPSR.
2249    MI->getOperand(5).setReg(ARM::CPSR);
2250    MI->getOperand(5).setIsDef(true);
2251    assert(!isPredicated(MI) && "Can't use flags from predicated instruction");
2252    CmpInstr->eraseFromParent();
2253
2254    // Modify the condition code of operands in OperandsToUpdate.
2255    // Since we have SUB(r1, r2) and CMP(r2, r1), the condition code needs to
2256    // be changed from r2 > r1 to r1 < r2, from r2 < r1 to r1 > r2, etc.
2257    for (unsigned i = 0, e = OperandsToUpdate.size(); i < e; i++)
2258      OperandsToUpdate[i].first->setImm(OperandsToUpdate[i].second);
2259    return true;
2260  }
2261  }
2262
2263  return false;
2264}
2265
2266bool ARMBaseInstrInfo::FoldImmediate(MachineInstr *UseMI,
2267                                     MachineInstr *DefMI, unsigned Reg,
2268                                     MachineRegisterInfo *MRI) const {
2269  // Fold large immediates into add, sub, or, xor.
2270  unsigned DefOpc = DefMI->getOpcode();
2271  if (DefOpc != ARM::t2MOVi32imm && DefOpc != ARM::MOVi32imm)
2272    return false;
2273  if (!DefMI->getOperand(1).isImm())
2274    // Could be t2MOVi32imm <ga:xx>
2275    return false;
2276
2277  if (!MRI->hasOneNonDBGUse(Reg))
2278    return false;
2279
2280  const MCInstrDesc &DefMCID = DefMI->getDesc();
2281  if (DefMCID.hasOptionalDef()) {
2282    unsigned NumOps = DefMCID.getNumOperands();
2283    const MachineOperand &MO = DefMI->getOperand(NumOps-1);
2284    if (MO.getReg() == ARM::CPSR && !MO.isDead())
2285      // If DefMI defines CPSR and it is not dead, it's obviously not safe
2286      // to delete DefMI.
2287      return false;
2288  }
2289
2290  const MCInstrDesc &UseMCID = UseMI->getDesc();
2291  if (UseMCID.hasOptionalDef()) {
2292    unsigned NumOps = UseMCID.getNumOperands();
2293    if (UseMI->getOperand(NumOps-1).getReg() == ARM::CPSR)
2294      // If the instruction sets the flag, do not attempt this optimization
2295      // since it may change the semantics of the code.
2296      return false;
2297  }
2298
2299  unsigned UseOpc = UseMI->getOpcode();
2300  unsigned NewUseOpc = 0;
2301  uint32_t ImmVal = (uint32_t)DefMI->getOperand(1).getImm();
2302  uint32_t SOImmValV1 = 0, SOImmValV2 = 0;
2303  bool Commute = false;
2304  switch (UseOpc) {
2305  default: return false;
2306  case ARM::SUBrr:
2307  case ARM::ADDrr:
2308  case ARM::ORRrr:
2309  case ARM::EORrr:
2310  case ARM::t2SUBrr:
2311  case ARM::t2ADDrr:
2312  case ARM::t2ORRrr:
2313  case ARM::t2EORrr: {
2314    Commute = UseMI->getOperand(2).getReg() != Reg;
2315    switch (UseOpc) {
2316    default: break;
2317    case ARM::SUBrr: {
2318      if (Commute)
2319        return false;
2320      ImmVal = -ImmVal;
2321      NewUseOpc = ARM::SUBri;
2322      // Fallthrough
2323    }
2324    case ARM::ADDrr:
2325    case ARM::ORRrr:
2326    case ARM::EORrr: {
2327      if (!ARM_AM::isSOImmTwoPartVal(ImmVal))
2328        return false;
2329      SOImmValV1 = (uint32_t)ARM_AM::getSOImmTwoPartFirst(ImmVal);
2330      SOImmValV2 = (uint32_t)ARM_AM::getSOImmTwoPartSecond(ImmVal);
2331      switch (UseOpc) {
2332      default: break;
2333      case ARM::ADDrr: NewUseOpc = ARM::ADDri; break;
2334      case ARM::ORRrr: NewUseOpc = ARM::ORRri; break;
2335      case ARM::EORrr: NewUseOpc = ARM::EORri; break;
2336      }
2337      break;
2338    }
2339    case ARM::t2SUBrr: {
2340      if (Commute)
2341        return false;
2342      ImmVal = -ImmVal;
2343      NewUseOpc = ARM::t2SUBri;
2344      // Fallthrough
2345    }
2346    case ARM::t2ADDrr:
2347    case ARM::t2ORRrr:
2348    case ARM::t2EORrr: {
2349      if (!ARM_AM::isT2SOImmTwoPartVal(ImmVal))
2350        return false;
2351      SOImmValV1 = (uint32_t)ARM_AM::getT2SOImmTwoPartFirst(ImmVal);
2352      SOImmValV2 = (uint32_t)ARM_AM::getT2SOImmTwoPartSecond(ImmVal);
2353      switch (UseOpc) {
2354      default: break;
2355      case ARM::t2ADDrr: NewUseOpc = ARM::t2ADDri; break;
2356      case ARM::t2ORRrr: NewUseOpc = ARM::t2ORRri; break;
2357      case ARM::t2EORrr: NewUseOpc = ARM::t2EORri; break;
2358      }
2359      break;
2360    }
2361    }
2362  }
2363  }
2364
2365  unsigned OpIdx = Commute ? 2 : 1;
2366  unsigned Reg1 = UseMI->getOperand(OpIdx).getReg();
2367  bool isKill = UseMI->getOperand(OpIdx).isKill();
2368  unsigned NewReg = MRI->createVirtualRegister(MRI->getRegClass(Reg));
2369  AddDefaultCC(AddDefaultPred(BuildMI(*UseMI->getParent(),
2370                                      UseMI, UseMI->getDebugLoc(),
2371                                      get(NewUseOpc), NewReg)
2372                              .addReg(Reg1, getKillRegState(isKill))
2373                              .addImm(SOImmValV1)));
2374  UseMI->setDesc(get(NewUseOpc));
2375  UseMI->getOperand(1).setReg(NewReg);
2376  UseMI->getOperand(1).setIsKill();
2377  UseMI->getOperand(2).ChangeToImmediate(SOImmValV2);
2378  DefMI->eraseFromParent();
2379  return true;
2380}
2381
2382static unsigned getNumMicroOpsSwiftLdSt(const InstrItineraryData *ItinData,
2383                                        const MachineInstr *MI) {
2384  switch (MI->getOpcode()) {
2385  default: {
2386    const MCInstrDesc &Desc = MI->getDesc();
2387    int UOps = ItinData->getNumMicroOps(Desc.getSchedClass());
2388    assert(UOps >= 0 && "bad # UOps");
2389    return UOps;
2390  }
2391
2392  case ARM::LDRrs:
2393  case ARM::LDRBrs:
2394  case ARM::STRrs:
2395  case ARM::STRBrs: {
2396    unsigned ShOpVal = MI->getOperand(3).getImm();
2397    bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
2398    unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
2399    if (!isSub &&
2400        (ShImm == 0 ||
2401         ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
2402          ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
2403      return 1;
2404    return 2;
2405  }
2406
2407  case ARM::LDRH:
2408  case ARM::STRH: {
2409    if (!MI->getOperand(2).getReg())
2410      return 1;
2411
2412    unsigned ShOpVal = MI->getOperand(3).getImm();
2413    bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
2414    unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
2415    if (!isSub &&
2416        (ShImm == 0 ||
2417         ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
2418          ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
2419      return 1;
2420    return 2;
2421  }
2422
2423  case ARM::LDRSB:
2424  case ARM::LDRSH:
2425    return (ARM_AM::getAM3Op(MI->getOperand(3).getImm()) == ARM_AM::sub) ? 3:2;
2426
2427  case ARM::LDRSB_POST:
2428  case ARM::LDRSH_POST: {
2429    unsigned Rt = MI->getOperand(0).getReg();
2430    unsigned Rm = MI->getOperand(3).getReg();
2431    return (Rt == Rm) ? 4 : 3;
2432  }
2433
2434  case ARM::LDR_PRE_REG:
2435  case ARM::LDRB_PRE_REG: {
2436    unsigned Rt = MI->getOperand(0).getReg();
2437    unsigned Rm = MI->getOperand(3).getReg();
2438    if (Rt == Rm)
2439      return 3;
2440    unsigned ShOpVal = MI->getOperand(4).getImm();
2441    bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
2442    unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
2443    if (!isSub &&
2444        (ShImm == 0 ||
2445         ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
2446          ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
2447      return 2;
2448    return 3;
2449  }
2450
2451  case ARM::STR_PRE_REG:
2452  case ARM::STRB_PRE_REG: {
2453    unsigned ShOpVal = MI->getOperand(4).getImm();
2454    bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
2455    unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
2456    if (!isSub &&
2457        (ShImm == 0 ||
2458         ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
2459          ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
2460      return 2;
2461    return 3;
2462  }
2463
2464  case ARM::LDRH_PRE:
2465  case ARM::STRH_PRE: {
2466    unsigned Rt = MI->getOperand(0).getReg();
2467    unsigned Rm = MI->getOperand(3).getReg();
2468    if (!Rm)
2469      return 2;
2470    if (Rt == Rm)
2471      return 3;
2472    return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub)
2473      ? 3 : 2;
2474  }
2475
2476  case ARM::LDR_POST_REG:
2477  case ARM::LDRB_POST_REG:
2478  case ARM::LDRH_POST: {
2479    unsigned Rt = MI->getOperand(0).getReg();
2480    unsigned Rm = MI->getOperand(3).getReg();
2481    return (Rt == Rm) ? 3 : 2;
2482  }
2483
2484  case ARM::LDR_PRE_IMM:
2485  case ARM::LDRB_PRE_IMM:
2486  case ARM::LDR_POST_IMM:
2487  case ARM::LDRB_POST_IMM:
2488  case ARM::STRB_POST_IMM:
2489  case ARM::STRB_POST_REG:
2490  case ARM::STRB_PRE_IMM:
2491  case ARM::STRH_POST:
2492  case ARM::STR_POST_IMM:
2493  case ARM::STR_POST_REG:
2494  case ARM::STR_PRE_IMM:
2495    return 2;
2496
2497  case ARM::LDRSB_PRE:
2498  case ARM::LDRSH_PRE: {
2499    unsigned Rm = MI->getOperand(3).getReg();
2500    if (Rm == 0)
2501      return 3;
2502    unsigned Rt = MI->getOperand(0).getReg();
2503    if (Rt == Rm)
2504      return 4;
2505    unsigned ShOpVal = MI->getOperand(4).getImm();
2506    bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
2507    unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
2508    if (!isSub &&
2509        (ShImm == 0 ||
2510         ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
2511          ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
2512      return 3;
2513    return 4;
2514  }
2515
2516  case ARM::LDRD: {
2517    unsigned Rt = MI->getOperand(0).getReg();
2518    unsigned Rn = MI->getOperand(2).getReg();
2519    unsigned Rm = MI->getOperand(3).getReg();
2520    if (Rm)
2521      return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ?4:3;
2522    return (Rt == Rn) ? 3 : 2;
2523  }
2524
2525  case ARM::STRD: {
2526    unsigned Rm = MI->getOperand(3).getReg();
2527    if (Rm)
2528      return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ?4:3;
2529    return 2;
2530  }
2531
2532  case ARM::LDRD_POST:
2533  case ARM::t2LDRD_POST:
2534    return 3;
2535
2536  case ARM::STRD_POST:
2537  case ARM::t2STRD_POST:
2538    return 4;
2539
2540  case ARM::LDRD_PRE: {
2541    unsigned Rt = MI->getOperand(0).getReg();
2542    unsigned Rn = MI->getOperand(3).getReg();
2543    unsigned Rm = MI->getOperand(4).getReg();
2544    if (Rm)
2545      return (ARM_AM::getAM3Op(MI->getOperand(5).getImm()) == ARM_AM::sub) ?5:4;
2546    return (Rt == Rn) ? 4 : 3;
2547  }
2548
2549  case ARM::t2LDRD_PRE: {
2550    unsigned Rt = MI->getOperand(0).getReg();
2551    unsigned Rn = MI->getOperand(3).getReg();
2552    return (Rt == Rn) ? 4 : 3;
2553  }
2554
2555  case ARM::STRD_PRE: {
2556    unsigned Rm = MI->getOperand(4).getReg();
2557    if (Rm)
2558      return (ARM_AM::getAM3Op(MI->getOperand(5).getImm()) == ARM_AM::sub) ?5:4;
2559    return 3;
2560  }
2561
2562  case ARM::t2STRD_PRE:
2563    return 3;
2564
2565  case ARM::t2LDR_POST:
2566  case ARM::t2LDRB_POST:
2567  case ARM::t2LDRB_PRE:
2568  case ARM::t2LDRSBi12:
2569  case ARM::t2LDRSBi8:
2570  case ARM::t2LDRSBpci:
2571  case ARM::t2LDRSBs:
2572  case ARM::t2LDRH_POST:
2573  case ARM::t2LDRH_PRE:
2574  case ARM::t2LDRSBT:
2575  case ARM::t2LDRSB_POST:
2576  case ARM::t2LDRSB_PRE:
2577  case ARM::t2LDRSH_POST:
2578  case ARM::t2LDRSH_PRE:
2579  case ARM::t2LDRSHi12:
2580  case ARM::t2LDRSHi8:
2581  case ARM::t2LDRSHpci:
2582  case ARM::t2LDRSHs:
2583    return 2;
2584
2585  case ARM::t2LDRDi8: {
2586    unsigned Rt = MI->getOperand(0).getReg();
2587    unsigned Rn = MI->getOperand(2).getReg();
2588    return (Rt == Rn) ? 3 : 2;
2589  }
2590
2591  case ARM::t2STRB_POST:
2592  case ARM::t2STRB_PRE:
2593  case ARM::t2STRBs:
2594  case ARM::t2STRDi8:
2595  case ARM::t2STRH_POST:
2596  case ARM::t2STRH_PRE:
2597  case ARM::t2STRHs:
2598  case ARM::t2STR_POST:
2599  case ARM::t2STR_PRE:
2600  case ARM::t2STRs:
2601    return 2;
2602  }
2603}
2604
2605// Return the number of 32-bit words loaded by LDM or stored by STM. If this
2606// can't be easily determined return 0 (missing MachineMemOperand).
2607//
2608// FIXME: The current MachineInstr design does not support relying on machine
2609// mem operands to determine the width of a memory access. Instead, we expect
2610// the target to provide this information based on the instruction opcode and
2611// operands. However, using MachineMemOperand is a the best solution now for
2612// two reasons:
2613//
2614// 1) getNumMicroOps tries to infer LDM memory width from the total number of MI
2615// operands. This is much more dangerous than using the MachineMemOperand
2616// sizes because CodeGen passes can insert/remove optional machine operands. In
2617// fact, it's totally incorrect for preRA passes and appears to be wrong for
2618// postRA passes as well.
2619//
2620// 2) getNumLDMAddresses is only used by the scheduling machine model and any
2621// machine model that calls this should handle the unknown (zero size) case.
2622//
2623// Long term, we should require a target hook that verifies MachineMemOperand
2624// sizes during MC lowering. That target hook should be local to MC lowering
2625// because we can't ensure that it is aware of other MI forms. Doing this will
2626// ensure that MachineMemOperands are correctly propagated through all passes.
2627unsigned ARMBaseInstrInfo::getNumLDMAddresses(const MachineInstr *MI) const {
2628  unsigned Size = 0;
2629  for (MachineInstr::mmo_iterator I = MI->memoperands_begin(),
2630         E = MI->memoperands_end(); I != E; ++I) {
2631    Size += (*I)->getSize();
2632  }
2633  return Size / 4;
2634}
2635
2636unsigned
2637ARMBaseInstrInfo::getNumMicroOps(const InstrItineraryData *ItinData,
2638                                 const MachineInstr *MI) const {
2639  if (!ItinData || ItinData->isEmpty())
2640    return 1;
2641
2642  const MCInstrDesc &Desc = MI->getDesc();
2643  unsigned Class = Desc.getSchedClass();
2644  int ItinUOps = ItinData->getNumMicroOps(Class);
2645  if (ItinUOps >= 0) {
2646    if (Subtarget.isSwift() && (Desc.mayLoad() || Desc.mayStore()))
2647      return getNumMicroOpsSwiftLdSt(ItinData, MI);
2648
2649    return ItinUOps;
2650  }
2651
2652  unsigned Opc = MI->getOpcode();
2653  switch (Opc) {
2654  default:
2655    llvm_unreachable("Unexpected multi-uops instruction!");
2656  case ARM::VLDMQIA:
2657  case ARM::VSTMQIA:
2658    return 2;
2659
2660  // The number of uOps for load / store multiple are determined by the number
2661  // registers.
2662  //
2663  // On Cortex-A8, each pair of register loads / stores can be scheduled on the
2664  // same cycle. The scheduling for the first load / store must be done
2665  // separately by assuming the address is not 64-bit aligned.
2666  //
2667  // On Cortex-A9, the formula is simply (#reg / 2) + (#reg % 2). If the address
2668  // is not 64-bit aligned, then AGU would take an extra cycle.  For VFP / NEON
2669  // load / store multiple, the formula is (#reg / 2) + (#reg % 2) + 1.
2670  case ARM::VLDMDIA:
2671  case ARM::VLDMDIA_UPD:
2672  case ARM::VLDMDDB_UPD:
2673  case ARM::VLDMSIA:
2674  case ARM::VLDMSIA_UPD:
2675  case ARM::VLDMSDB_UPD:
2676  case ARM::VSTMDIA:
2677  case ARM::VSTMDIA_UPD:
2678  case ARM::VSTMDDB_UPD:
2679  case ARM::VSTMSIA:
2680  case ARM::VSTMSIA_UPD:
2681  case ARM::VSTMSDB_UPD: {
2682    unsigned NumRegs = MI->getNumOperands() - Desc.getNumOperands();
2683    return (NumRegs / 2) + (NumRegs % 2) + 1;
2684  }
2685
2686  case ARM::LDMIA_RET:
2687  case ARM::LDMIA:
2688  case ARM::LDMDA:
2689  case ARM::LDMDB:
2690  case ARM::LDMIB:
2691  case ARM::LDMIA_UPD:
2692  case ARM::LDMDA_UPD:
2693  case ARM::LDMDB_UPD:
2694  case ARM::LDMIB_UPD:
2695  case ARM::STMIA:
2696  case ARM::STMDA:
2697  case ARM::STMDB:
2698  case ARM::STMIB:
2699  case ARM::STMIA_UPD:
2700  case ARM::STMDA_UPD:
2701  case ARM::STMDB_UPD:
2702  case ARM::STMIB_UPD:
2703  case ARM::tLDMIA:
2704  case ARM::tLDMIA_UPD:
2705  case ARM::tSTMIA_UPD:
2706  case ARM::tPOP_RET:
2707  case ARM::tPOP:
2708  case ARM::tPUSH:
2709  case ARM::t2LDMIA_RET:
2710  case ARM::t2LDMIA:
2711  case ARM::t2LDMDB:
2712  case ARM::t2LDMIA_UPD:
2713  case ARM::t2LDMDB_UPD:
2714  case ARM::t2STMIA:
2715  case ARM::t2STMDB:
2716  case ARM::t2STMIA_UPD:
2717  case ARM::t2STMDB_UPD: {
2718    unsigned NumRegs = MI->getNumOperands() - Desc.getNumOperands() + 1;
2719    if (Subtarget.isSwift()) {
2720      // rdar://8402126
2721      int UOps = 1 + NumRegs;  // One for address computation, one for each ld / st.
2722      switch (Opc) {
2723      default: break;
2724      case ARM::VLDMDIA_UPD:
2725      case ARM::VLDMDDB_UPD:
2726      case ARM::VLDMSIA_UPD:
2727      case ARM::VLDMSDB_UPD:
2728      case ARM::VSTMDIA_UPD:
2729      case ARM::VSTMDDB_UPD:
2730      case ARM::VSTMSIA_UPD:
2731      case ARM::VSTMSDB_UPD:
2732      case ARM::LDMIA_UPD:
2733      case ARM::LDMDA_UPD:
2734      case ARM::LDMDB_UPD:
2735      case ARM::LDMIB_UPD:
2736      case ARM::STMIA_UPD:
2737      case ARM::STMDA_UPD:
2738      case ARM::STMDB_UPD:
2739      case ARM::STMIB_UPD:
2740      case ARM::tLDMIA_UPD:
2741      case ARM::tSTMIA_UPD:
2742      case ARM::t2LDMIA_UPD:
2743      case ARM::t2LDMDB_UPD:
2744      case ARM::t2STMIA_UPD:
2745      case ARM::t2STMDB_UPD:
2746        ++UOps; // One for base register writeback.
2747        break;
2748      case ARM::LDMIA_RET:
2749      case ARM::tPOP_RET:
2750      case ARM::t2LDMIA_RET:
2751        UOps += 2; // One for base reg wb, one for write to pc.
2752        break;
2753      }
2754      return UOps;
2755    } else if (Subtarget.isCortexA8()) {
2756      if (NumRegs < 4)
2757        return 2;
2758      // 4 registers would be issued: 2, 2.
2759      // 5 registers would be issued: 2, 2, 1.
2760      int A8UOps = (NumRegs / 2);
2761      if (NumRegs % 2)
2762        ++A8UOps;
2763      return A8UOps;
2764    } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) {
2765      int A9UOps = (NumRegs / 2);
2766      // If there are odd number of registers or if it's not 64-bit aligned,
2767      // then it takes an extra AGU (Address Generation Unit) cycle.
2768      if ((NumRegs % 2) ||
2769          !MI->hasOneMemOperand() ||
2770          (*MI->memoperands_begin())->getAlignment() < 8)
2771        ++A9UOps;
2772      return A9UOps;
2773    } else {
2774      // Assume the worst.
2775      return NumRegs;
2776    }
2777  }
2778  }
2779}
2780
2781int
2782ARMBaseInstrInfo::getVLDMDefCycle(const InstrItineraryData *ItinData,
2783                                  const MCInstrDesc &DefMCID,
2784                                  unsigned DefClass,
2785                                  unsigned DefIdx, unsigned DefAlign) const {
2786  int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1;
2787  if (RegNo <= 0)
2788    // Def is the address writeback.
2789    return ItinData->getOperandCycle(DefClass, DefIdx);
2790
2791  int DefCycle;
2792  if (Subtarget.isCortexA8()) {
2793    // (regno / 2) + (regno % 2) + 1
2794    DefCycle = RegNo / 2 + 1;
2795    if (RegNo % 2)
2796      ++DefCycle;
2797  } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) {
2798    DefCycle = RegNo;
2799    bool isSLoad = false;
2800
2801    switch (DefMCID.getOpcode()) {
2802    default: break;
2803    case ARM::VLDMSIA:
2804    case ARM::VLDMSIA_UPD:
2805    case ARM::VLDMSDB_UPD:
2806      isSLoad = true;
2807      break;
2808    }
2809
2810    // If there are odd number of 'S' registers or if it's not 64-bit aligned,
2811    // then it takes an extra cycle.
2812    if ((isSLoad && (RegNo % 2)) || DefAlign < 8)
2813      ++DefCycle;
2814  } else {
2815    // Assume the worst.
2816    DefCycle = RegNo + 2;
2817  }
2818
2819  return DefCycle;
2820}
2821
2822int
2823ARMBaseInstrInfo::getLDMDefCycle(const InstrItineraryData *ItinData,
2824                                 const MCInstrDesc &DefMCID,
2825                                 unsigned DefClass,
2826                                 unsigned DefIdx, unsigned DefAlign) const {
2827  int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1;
2828  if (RegNo <= 0)
2829    // Def is the address writeback.
2830    return ItinData->getOperandCycle(DefClass, DefIdx);
2831
2832  int DefCycle;
2833  if (Subtarget.isCortexA8()) {
2834    // 4 registers would be issued: 1, 2, 1.
2835    // 5 registers would be issued: 1, 2, 2.
2836    DefCycle = RegNo / 2;
2837    if (DefCycle < 1)
2838      DefCycle = 1;
2839    // Result latency is issue cycle + 2: E2.
2840    DefCycle += 2;
2841  } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) {
2842    DefCycle = (RegNo / 2);
2843    // If there are odd number of registers or if it's not 64-bit aligned,
2844    // then it takes an extra AGU (Address Generation Unit) cycle.
2845    if ((RegNo % 2) || DefAlign < 8)
2846      ++DefCycle;
2847    // Result latency is AGU cycles + 2.
2848    DefCycle += 2;
2849  } else {
2850    // Assume the worst.
2851    DefCycle = RegNo + 2;
2852  }
2853
2854  return DefCycle;
2855}
2856
2857int
2858ARMBaseInstrInfo::getVSTMUseCycle(const InstrItineraryData *ItinData,
2859                                  const MCInstrDesc &UseMCID,
2860                                  unsigned UseClass,
2861                                  unsigned UseIdx, unsigned UseAlign) const {
2862  int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1;
2863  if (RegNo <= 0)
2864    return ItinData->getOperandCycle(UseClass, UseIdx);
2865
2866  int UseCycle;
2867  if (Subtarget.isCortexA8()) {
2868    // (regno / 2) + (regno % 2) + 1
2869    UseCycle = RegNo / 2 + 1;
2870    if (RegNo % 2)
2871      ++UseCycle;
2872  } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) {
2873    UseCycle = RegNo;
2874    bool isSStore = false;
2875
2876    switch (UseMCID.getOpcode()) {
2877    default: break;
2878    case ARM::VSTMSIA:
2879    case ARM::VSTMSIA_UPD:
2880    case ARM::VSTMSDB_UPD:
2881      isSStore = true;
2882      break;
2883    }
2884
2885    // If there are odd number of 'S' registers or if it's not 64-bit aligned,
2886    // then it takes an extra cycle.
2887    if ((isSStore && (RegNo % 2)) || UseAlign < 8)
2888      ++UseCycle;
2889  } else {
2890    // Assume the worst.
2891    UseCycle = RegNo + 2;
2892  }
2893
2894  return UseCycle;
2895}
2896
2897int
2898ARMBaseInstrInfo::getSTMUseCycle(const InstrItineraryData *ItinData,
2899                                 const MCInstrDesc &UseMCID,
2900                                 unsigned UseClass,
2901                                 unsigned UseIdx, unsigned UseAlign) const {
2902  int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1;
2903  if (RegNo <= 0)
2904    return ItinData->getOperandCycle(UseClass, UseIdx);
2905
2906  int UseCycle;
2907  if (Subtarget.isCortexA8()) {
2908    UseCycle = RegNo / 2;
2909    if (UseCycle < 2)
2910      UseCycle = 2;
2911    // Read in E3.
2912    UseCycle += 2;
2913  } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) {
2914    UseCycle = (RegNo / 2);
2915    // If there are odd number of registers or if it's not 64-bit aligned,
2916    // then it takes an extra AGU (Address Generation Unit) cycle.
2917    if ((RegNo % 2) || UseAlign < 8)
2918      ++UseCycle;
2919  } else {
2920    // Assume the worst.
2921    UseCycle = 1;
2922  }
2923  return UseCycle;
2924}
2925
2926int
2927ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData,
2928                                    const MCInstrDesc &DefMCID,
2929                                    unsigned DefIdx, unsigned DefAlign,
2930                                    const MCInstrDesc &UseMCID,
2931                                    unsigned UseIdx, unsigned UseAlign) const {
2932  unsigned DefClass = DefMCID.getSchedClass();
2933  unsigned UseClass = UseMCID.getSchedClass();
2934
2935  if (DefIdx < DefMCID.getNumDefs() && UseIdx < UseMCID.getNumOperands())
2936    return ItinData->getOperandLatency(DefClass, DefIdx, UseClass, UseIdx);
2937
2938  // This may be a def / use of a variable_ops instruction, the operand
2939  // latency might be determinable dynamically. Let the target try to
2940  // figure it out.
2941  int DefCycle = -1;
2942  bool LdmBypass = false;
2943  switch (DefMCID.getOpcode()) {
2944  default:
2945    DefCycle = ItinData->getOperandCycle(DefClass, DefIdx);
2946    break;
2947
2948  case ARM::VLDMDIA:
2949  case ARM::VLDMDIA_UPD:
2950  case ARM::VLDMDDB_UPD:
2951  case ARM::VLDMSIA:
2952  case ARM::VLDMSIA_UPD:
2953  case ARM::VLDMSDB_UPD:
2954    DefCycle = getVLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign);
2955    break;
2956
2957  case ARM::LDMIA_RET:
2958  case ARM::LDMIA:
2959  case ARM::LDMDA:
2960  case ARM::LDMDB:
2961  case ARM::LDMIB:
2962  case ARM::LDMIA_UPD:
2963  case ARM::LDMDA_UPD:
2964  case ARM::LDMDB_UPD:
2965  case ARM::LDMIB_UPD:
2966  case ARM::tLDMIA:
2967  case ARM::tLDMIA_UPD:
2968  case ARM::tPUSH:
2969  case ARM::t2LDMIA_RET:
2970  case ARM::t2LDMIA:
2971  case ARM::t2LDMDB:
2972  case ARM::t2LDMIA_UPD:
2973  case ARM::t2LDMDB_UPD:
2974    LdmBypass = 1;
2975    DefCycle = getLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign);
2976    break;
2977  }
2978
2979  if (DefCycle == -1)
2980    // We can't seem to determine the result latency of the def, assume it's 2.
2981    DefCycle = 2;
2982
2983  int UseCycle = -1;
2984  switch (UseMCID.getOpcode()) {
2985  default:
2986    UseCycle = ItinData->getOperandCycle(UseClass, UseIdx);
2987    break;
2988
2989  case ARM::VSTMDIA:
2990  case ARM::VSTMDIA_UPD:
2991  case ARM::VSTMDDB_UPD:
2992  case ARM::VSTMSIA:
2993  case ARM::VSTMSIA_UPD:
2994  case ARM::VSTMSDB_UPD:
2995    UseCycle = getVSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign);
2996    break;
2997
2998  case ARM::STMIA:
2999  case ARM::STMDA:
3000  case ARM::STMDB:
3001  case ARM::STMIB:
3002  case ARM::STMIA_UPD:
3003  case ARM::STMDA_UPD:
3004  case ARM::STMDB_UPD:
3005  case ARM::STMIB_UPD:
3006  case ARM::tSTMIA_UPD:
3007  case ARM::tPOP_RET:
3008  case ARM::tPOP:
3009  case ARM::t2STMIA:
3010  case ARM::t2STMDB:
3011  case ARM::t2STMIA_UPD:
3012  case ARM::t2STMDB_UPD:
3013    UseCycle = getSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign);
3014    break;
3015  }
3016
3017  if (UseCycle == -1)
3018    // Assume it's read in the first stage.
3019    UseCycle = 1;
3020
3021  UseCycle = DefCycle - UseCycle + 1;
3022  if (UseCycle > 0) {
3023    if (LdmBypass) {
3024      // It's a variable_ops instruction so we can't use DefIdx here. Just use
3025      // first def operand.
3026      if (ItinData->hasPipelineForwarding(DefClass, DefMCID.getNumOperands()-1,
3027                                          UseClass, UseIdx))
3028        --UseCycle;
3029    } else if (ItinData->hasPipelineForwarding(DefClass, DefIdx,
3030                                               UseClass, UseIdx)) {
3031      --UseCycle;
3032    }
3033  }
3034
3035  return UseCycle;
3036}
3037
3038static const MachineInstr *getBundledDefMI(const TargetRegisterInfo *TRI,
3039                                           const MachineInstr *MI, unsigned Reg,
3040                                           unsigned &DefIdx, unsigned &Dist) {
3041  Dist = 0;
3042
3043  MachineBasicBlock::const_iterator I = MI; ++I;
3044  MachineBasicBlock::const_instr_iterator II =
3045    llvm::prior(I.getInstrIterator());
3046  assert(II->isInsideBundle() && "Empty bundle?");
3047
3048  int Idx = -1;
3049  while (II->isInsideBundle()) {
3050    Idx = II->findRegisterDefOperandIdx(Reg, false, true, TRI);
3051    if (Idx != -1)
3052      break;
3053    --II;
3054    ++Dist;
3055  }
3056
3057  assert(Idx != -1 && "Cannot find bundled definition!");
3058  DefIdx = Idx;
3059  return II;
3060}
3061
3062static const MachineInstr *getBundledUseMI(const TargetRegisterInfo *TRI,
3063                                           const MachineInstr *MI, unsigned Reg,
3064                                           unsigned &UseIdx, unsigned &Dist) {
3065  Dist = 0;
3066
3067  MachineBasicBlock::const_instr_iterator II = MI; ++II;
3068  assert(II->isInsideBundle() && "Empty bundle?");
3069  MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
3070
3071  // FIXME: This doesn't properly handle multiple uses.
3072  int Idx = -1;
3073  while (II != E && II->isInsideBundle()) {
3074    Idx = II->findRegisterUseOperandIdx(Reg, false, TRI);
3075    if (Idx != -1)
3076      break;
3077    if (II->getOpcode() != ARM::t2IT)
3078      ++Dist;
3079    ++II;
3080  }
3081
3082  if (Idx == -1) {
3083    Dist = 0;
3084    return 0;
3085  }
3086
3087  UseIdx = Idx;
3088  return II;
3089}
3090
3091/// Return the number of cycles to add to (or subtract from) the static
3092/// itinerary based on the def opcode and alignment. The caller will ensure that
3093/// adjusted latency is at least one cycle.
3094static int adjustDefLatency(const ARMSubtarget &Subtarget,
3095                            const MachineInstr *DefMI,
3096                            const MCInstrDesc *DefMCID, unsigned DefAlign) {
3097  int Adjust = 0;
3098  if (Subtarget.isCortexA8() || Subtarget.isLikeA9()) {
3099    // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2]
3100    // variants are one cycle cheaper.
3101    switch (DefMCID->getOpcode()) {
3102    default: break;
3103    case ARM::LDRrs:
3104    case ARM::LDRBrs: {
3105      unsigned ShOpVal = DefMI->getOperand(3).getImm();
3106      unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
3107      if (ShImm == 0 ||
3108          (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))
3109        --Adjust;
3110      break;
3111    }
3112    case ARM::t2LDRs:
3113    case ARM::t2LDRBs:
3114    case ARM::t2LDRHs:
3115    case ARM::t2LDRSHs: {
3116      // Thumb2 mode: lsl only.
3117      unsigned ShAmt = DefMI->getOperand(3).getImm();
3118      if (ShAmt == 0 || ShAmt == 2)
3119        --Adjust;
3120      break;
3121    }
3122    }
3123  } else if (Subtarget.isSwift()) {
3124    // FIXME: Properly handle all of the latency adjustments for address
3125    // writeback.
3126    switch (DefMCID->getOpcode()) {
3127    default: break;
3128    case ARM::LDRrs:
3129    case ARM::LDRBrs: {
3130      unsigned ShOpVal = DefMI->getOperand(3).getImm();
3131      bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub;
3132      unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
3133      if (!isSub &&
3134          (ShImm == 0 ||
3135           ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
3136            ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)))
3137        Adjust -= 2;
3138      else if (!isSub &&
3139               ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr)
3140        --Adjust;
3141      break;
3142    }
3143    case ARM::t2LDRs:
3144    case ARM::t2LDRBs:
3145    case ARM::t2LDRHs:
3146    case ARM::t2LDRSHs: {
3147      // Thumb2 mode: lsl only.
3148      unsigned ShAmt = DefMI->getOperand(3).getImm();
3149      if (ShAmt == 0 || ShAmt == 1 || ShAmt == 2 || ShAmt == 3)
3150        Adjust -= 2;
3151      break;
3152    }
3153    }
3154  }
3155
3156  if (DefAlign < 8 && Subtarget.isLikeA9()) {
3157    switch (DefMCID->getOpcode()) {
3158    default: break;
3159    case ARM::VLD1q8:
3160    case ARM::VLD1q16:
3161    case ARM::VLD1q32:
3162    case ARM::VLD1q64:
3163    case ARM::VLD1q8wb_fixed:
3164    case ARM::VLD1q16wb_fixed:
3165    case ARM::VLD1q32wb_fixed:
3166    case ARM::VLD1q64wb_fixed:
3167    case ARM::VLD1q8wb_register:
3168    case ARM::VLD1q16wb_register:
3169    case ARM::VLD1q32wb_register:
3170    case ARM::VLD1q64wb_register:
3171    case ARM::VLD2d8:
3172    case ARM::VLD2d16:
3173    case ARM::VLD2d32:
3174    case ARM::VLD2q8:
3175    case ARM::VLD2q16:
3176    case ARM::VLD2q32:
3177    case ARM::VLD2d8wb_fixed:
3178    case ARM::VLD2d16wb_fixed:
3179    case ARM::VLD2d32wb_fixed:
3180    case ARM::VLD2q8wb_fixed:
3181    case ARM::VLD2q16wb_fixed:
3182    case ARM::VLD2q32wb_fixed:
3183    case ARM::VLD2d8wb_register:
3184    case ARM::VLD2d16wb_register:
3185    case ARM::VLD2d32wb_register:
3186    case ARM::VLD2q8wb_register:
3187    case ARM::VLD2q16wb_register:
3188    case ARM::VLD2q32wb_register:
3189    case ARM::VLD3d8:
3190    case ARM::VLD3d16:
3191    case ARM::VLD3d32:
3192    case ARM::VLD1d64T:
3193    case ARM::VLD3d8_UPD:
3194    case ARM::VLD3d16_UPD:
3195    case ARM::VLD3d32_UPD:
3196    case ARM::VLD1d64Twb_fixed:
3197    case ARM::VLD1d64Twb_register:
3198    case ARM::VLD3q8_UPD:
3199    case ARM::VLD3q16_UPD:
3200    case ARM::VLD3q32_UPD:
3201    case ARM::VLD4d8:
3202    case ARM::VLD4d16:
3203    case ARM::VLD4d32:
3204    case ARM::VLD1d64Q:
3205    case ARM::VLD4d8_UPD:
3206    case ARM::VLD4d16_UPD:
3207    case ARM::VLD4d32_UPD:
3208    case ARM::VLD1d64Qwb_fixed:
3209    case ARM::VLD1d64Qwb_register:
3210    case ARM::VLD4q8_UPD:
3211    case ARM::VLD4q16_UPD:
3212    case ARM::VLD4q32_UPD:
3213    case ARM::VLD1DUPq8:
3214    case ARM::VLD1DUPq16:
3215    case ARM::VLD1DUPq32:
3216    case ARM::VLD1DUPq8wb_fixed:
3217    case ARM::VLD1DUPq16wb_fixed:
3218    case ARM::VLD1DUPq32wb_fixed:
3219    case ARM::VLD1DUPq8wb_register:
3220    case ARM::VLD1DUPq16wb_register:
3221    case ARM::VLD1DUPq32wb_register:
3222    case ARM::VLD2DUPd8:
3223    case ARM::VLD2DUPd16:
3224    case ARM::VLD2DUPd32:
3225    case ARM::VLD2DUPd8wb_fixed:
3226    case ARM::VLD2DUPd16wb_fixed:
3227    case ARM::VLD2DUPd32wb_fixed:
3228    case ARM::VLD2DUPd8wb_register:
3229    case ARM::VLD2DUPd16wb_register:
3230    case ARM::VLD2DUPd32wb_register:
3231    case ARM::VLD4DUPd8:
3232    case ARM::VLD4DUPd16:
3233    case ARM::VLD4DUPd32:
3234    case ARM::VLD4DUPd8_UPD:
3235    case ARM::VLD4DUPd16_UPD:
3236    case ARM::VLD4DUPd32_UPD:
3237    case ARM::VLD1LNd8:
3238    case ARM::VLD1LNd16:
3239    case ARM::VLD1LNd32:
3240    case ARM::VLD1LNd8_UPD:
3241    case ARM::VLD1LNd16_UPD:
3242    case ARM::VLD1LNd32_UPD:
3243    case ARM::VLD2LNd8:
3244    case ARM::VLD2LNd16:
3245    case ARM::VLD2LNd32:
3246    case ARM::VLD2LNq16:
3247    case ARM::VLD2LNq32:
3248    case ARM::VLD2LNd8_UPD:
3249    case ARM::VLD2LNd16_UPD:
3250    case ARM::VLD2LNd32_UPD:
3251    case ARM::VLD2LNq16_UPD:
3252    case ARM::VLD2LNq32_UPD:
3253    case ARM::VLD4LNd8:
3254    case ARM::VLD4LNd16:
3255    case ARM::VLD4LNd32:
3256    case ARM::VLD4LNq16:
3257    case ARM::VLD4LNq32:
3258    case ARM::VLD4LNd8_UPD:
3259    case ARM::VLD4LNd16_UPD:
3260    case ARM::VLD4LNd32_UPD:
3261    case ARM::VLD4LNq16_UPD:
3262    case ARM::VLD4LNq32_UPD:
3263      // If the address is not 64-bit aligned, the latencies of these
3264      // instructions increases by one.
3265      ++Adjust;
3266      break;
3267    }
3268  }
3269  return Adjust;
3270}
3271
3272
3273
3274int
3275ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData,
3276                                    const MachineInstr *DefMI, unsigned DefIdx,
3277                                    const MachineInstr *UseMI,
3278                                    unsigned UseIdx) const {
3279  // No operand latency. The caller may fall back to getInstrLatency.
3280  if (!ItinData || ItinData->isEmpty())
3281    return -1;
3282
3283  const MachineOperand &DefMO = DefMI->getOperand(DefIdx);
3284  unsigned Reg = DefMO.getReg();
3285  const MCInstrDesc *DefMCID = &DefMI->getDesc();
3286  const MCInstrDesc *UseMCID = &UseMI->getDesc();
3287
3288  unsigned DefAdj = 0;
3289  if (DefMI->isBundle()) {
3290    DefMI = getBundledDefMI(&getRegisterInfo(), DefMI, Reg, DefIdx, DefAdj);
3291    DefMCID = &DefMI->getDesc();
3292  }
3293  if (DefMI->isCopyLike() || DefMI->isInsertSubreg() ||
3294      DefMI->isRegSequence() || DefMI->isImplicitDef()) {
3295    return 1;
3296  }
3297
3298  unsigned UseAdj = 0;
3299  if (UseMI->isBundle()) {
3300    unsigned NewUseIdx;
3301    const MachineInstr *NewUseMI = getBundledUseMI(&getRegisterInfo(), UseMI,
3302                                                   Reg, NewUseIdx, UseAdj);
3303    if (!NewUseMI)
3304      return -1;
3305
3306    UseMI = NewUseMI;
3307    UseIdx = NewUseIdx;
3308    UseMCID = &UseMI->getDesc();
3309  }
3310
3311  if (Reg == ARM::CPSR) {
3312    if (DefMI->getOpcode() == ARM::FMSTAT) {
3313      // fpscr -> cpsr stalls over 20 cycles on A8 (and earlier?)
3314      return Subtarget.isLikeA9() ? 1 : 20;
3315    }
3316
3317    // CPSR set and branch can be paired in the same cycle.
3318    if (UseMI->isBranch())
3319      return 0;
3320
3321    // Otherwise it takes the instruction latency (generally one).
3322    unsigned Latency = getInstrLatency(ItinData, DefMI);
3323
3324    // For Thumb2 and -Os, prefer scheduling CPSR setting instruction close to
3325    // its uses. Instructions which are otherwise scheduled between them may
3326    // incur a code size penalty (not able to use the CPSR setting 16-bit
3327    // instructions).
3328    if (Latency > 0 && Subtarget.isThumb2()) {
3329      const MachineFunction *MF = DefMI->getParent()->getParent();
3330      if (MF->getFunction()->getFnAttributes().
3331            hasAttribute(Attributes::OptimizeForSize))
3332        --Latency;
3333    }
3334    return Latency;
3335  }
3336
3337  if (DefMO.isImplicit() || UseMI->getOperand(UseIdx).isImplicit())
3338    return -1;
3339
3340  unsigned DefAlign = DefMI->hasOneMemOperand()
3341    ? (*DefMI->memoperands_begin())->getAlignment() : 0;
3342  unsigned UseAlign = UseMI->hasOneMemOperand()
3343    ? (*UseMI->memoperands_begin())->getAlignment() : 0;
3344
3345  // Get the itinerary's latency if possible, and handle variable_ops.
3346  int Latency = getOperandLatency(ItinData, *DefMCID, DefIdx, DefAlign,
3347                                  *UseMCID, UseIdx, UseAlign);
3348  // Unable to find operand latency. The caller may resort to getInstrLatency.
3349  if (Latency < 0)
3350    return Latency;
3351
3352  // Adjust for IT block position.
3353  int Adj = DefAdj + UseAdj;
3354
3355  // Adjust for dynamic def-side opcode variants not captured by the itinerary.
3356  Adj += adjustDefLatency(Subtarget, DefMI, DefMCID, DefAlign);
3357  if (Adj >= 0 || (int)Latency > -Adj) {
3358    return Latency + Adj;
3359  }
3360  // Return the itinerary latency, which may be zero but not less than zero.
3361  return Latency;
3362}
3363
3364int
3365ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData,
3366                                    SDNode *DefNode, unsigned DefIdx,
3367                                    SDNode *UseNode, unsigned UseIdx) const {
3368  if (!DefNode->isMachineOpcode())
3369    return 1;
3370
3371  const MCInstrDesc &DefMCID = get(DefNode->getMachineOpcode());
3372
3373  if (isZeroCost(DefMCID.Opcode))
3374    return 0;
3375
3376  if (!ItinData || ItinData->isEmpty())
3377    return DefMCID.mayLoad() ? 3 : 1;
3378
3379  if (!UseNode->isMachineOpcode()) {
3380    int Latency = ItinData->getOperandCycle(DefMCID.getSchedClass(), DefIdx);
3381    if (Subtarget.isLikeA9() || Subtarget.isSwift())
3382      return Latency <= 2 ? 1 : Latency - 1;
3383    else
3384      return Latency <= 3 ? 1 : Latency - 2;
3385  }
3386
3387  const MCInstrDesc &UseMCID = get(UseNode->getMachineOpcode());
3388  const MachineSDNode *DefMN = dyn_cast<MachineSDNode>(DefNode);
3389  unsigned DefAlign = !DefMN->memoperands_empty()
3390    ? (*DefMN->memoperands_begin())->getAlignment() : 0;
3391  const MachineSDNode *UseMN = dyn_cast<MachineSDNode>(UseNode);
3392  unsigned UseAlign = !UseMN->memoperands_empty()
3393    ? (*UseMN->memoperands_begin())->getAlignment() : 0;
3394  int Latency = getOperandLatency(ItinData, DefMCID, DefIdx, DefAlign,
3395                                  UseMCID, UseIdx, UseAlign);
3396
3397  if (Latency > 1 &&
3398      (Subtarget.isCortexA8() || Subtarget.isLikeA9())) {
3399    // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2]
3400    // variants are one cycle cheaper.
3401    switch (DefMCID.getOpcode()) {
3402    default: break;
3403    case ARM::LDRrs:
3404    case ARM::LDRBrs: {
3405      unsigned ShOpVal =
3406        cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue();
3407      unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
3408      if (ShImm == 0 ||
3409          (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))
3410        --Latency;
3411      break;
3412    }
3413    case ARM::t2LDRs:
3414    case ARM::t2LDRBs:
3415    case ARM::t2LDRHs:
3416    case ARM::t2LDRSHs: {
3417      // Thumb2 mode: lsl only.
3418      unsigned ShAmt =
3419        cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue();
3420      if (ShAmt == 0 || ShAmt == 2)
3421        --Latency;
3422      break;
3423    }
3424    }
3425  } else if (DefIdx == 0 && Latency > 2 && Subtarget.isSwift()) {
3426    // FIXME: Properly handle all of the latency adjustments for address
3427    // writeback.
3428    switch (DefMCID.getOpcode()) {
3429    default: break;
3430    case ARM::LDRrs:
3431    case ARM::LDRBrs: {
3432      unsigned ShOpVal =
3433        cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue();
3434      unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal);
3435      if (ShImm == 0 ||
3436          ((ShImm == 1 || ShImm == 2 || ShImm == 3) &&
3437           ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))
3438        Latency -= 2;
3439      else if (ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr)
3440        --Latency;
3441      break;
3442    }
3443    case ARM::t2LDRs:
3444    case ARM::t2LDRBs:
3445    case ARM::t2LDRHs:
3446    case ARM::t2LDRSHs: {
3447      // Thumb2 mode: lsl 0-3 only.
3448      Latency -= 2;
3449      break;
3450    }
3451    }
3452  }
3453
3454  if (DefAlign < 8 && Subtarget.isLikeA9())
3455    switch (DefMCID.getOpcode()) {
3456    default: break;
3457    case ARM::VLD1q8:
3458    case ARM::VLD1q16:
3459    case ARM::VLD1q32:
3460    case ARM::VLD1q64:
3461    case ARM::VLD1q8wb_register:
3462    case ARM::VLD1q16wb_register:
3463    case ARM::VLD1q32wb_register:
3464    case ARM::VLD1q64wb_register:
3465    case ARM::VLD1q8wb_fixed:
3466    case ARM::VLD1q16wb_fixed:
3467    case ARM::VLD1q32wb_fixed:
3468    case ARM::VLD1q64wb_fixed:
3469    case ARM::VLD2d8:
3470    case ARM::VLD2d16:
3471    case ARM::VLD2d32:
3472    case ARM::VLD2q8Pseudo:
3473    case ARM::VLD2q16Pseudo:
3474    case ARM::VLD2q32Pseudo:
3475    case ARM::VLD2d8wb_fixed:
3476    case ARM::VLD2d16wb_fixed:
3477    case ARM::VLD2d32wb_fixed:
3478    case ARM::VLD2q8PseudoWB_fixed:
3479    case ARM::VLD2q16PseudoWB_fixed:
3480    case ARM::VLD2q32PseudoWB_fixed:
3481    case ARM::VLD2d8wb_register:
3482    case ARM::VLD2d16wb_register:
3483    case ARM::VLD2d32wb_register:
3484    case ARM::VLD2q8PseudoWB_register:
3485    case ARM::VLD2q16PseudoWB_register:
3486    case ARM::VLD2q32PseudoWB_register:
3487    case ARM::VLD3d8Pseudo:
3488    case ARM::VLD3d16Pseudo:
3489    case ARM::VLD3d32Pseudo:
3490    case ARM::VLD1d64TPseudo:
3491    case ARM::VLD3d8Pseudo_UPD:
3492    case ARM::VLD3d16Pseudo_UPD:
3493    case ARM::VLD3d32Pseudo_UPD:
3494    case ARM::VLD3q8Pseudo_UPD:
3495    case ARM::VLD3q16Pseudo_UPD:
3496    case ARM::VLD3q32Pseudo_UPD:
3497    case ARM::VLD3q8oddPseudo:
3498    case ARM::VLD3q16oddPseudo:
3499    case ARM::VLD3q32oddPseudo:
3500    case ARM::VLD3q8oddPseudo_UPD:
3501    case ARM::VLD3q16oddPseudo_UPD:
3502    case ARM::VLD3q32oddPseudo_UPD:
3503    case ARM::VLD4d8Pseudo:
3504    case ARM::VLD4d16Pseudo:
3505    case ARM::VLD4d32Pseudo:
3506    case ARM::VLD1d64QPseudo:
3507    case ARM::VLD4d8Pseudo_UPD:
3508    case ARM::VLD4d16Pseudo_UPD:
3509    case ARM::VLD4d32Pseudo_UPD:
3510    case ARM::VLD4q8Pseudo_UPD:
3511    case ARM::VLD4q16Pseudo_UPD:
3512    case ARM::VLD4q32Pseudo_UPD:
3513    case ARM::VLD4q8oddPseudo:
3514    case ARM::VLD4q16oddPseudo:
3515    case ARM::VLD4q32oddPseudo:
3516    case ARM::VLD4q8oddPseudo_UPD:
3517    case ARM::VLD4q16oddPseudo_UPD:
3518    case ARM::VLD4q32oddPseudo_UPD:
3519    case ARM::VLD1DUPq8:
3520    case ARM::VLD1DUPq16:
3521    case ARM::VLD1DUPq32:
3522    case ARM::VLD1DUPq8wb_fixed:
3523    case ARM::VLD1DUPq16wb_fixed:
3524    case ARM::VLD1DUPq32wb_fixed:
3525    case ARM::VLD1DUPq8wb_register:
3526    case ARM::VLD1DUPq16wb_register:
3527    case ARM::VLD1DUPq32wb_register:
3528    case ARM::VLD2DUPd8:
3529    case ARM::VLD2DUPd16:
3530    case ARM::VLD2DUPd32:
3531    case ARM::VLD2DUPd8wb_fixed:
3532    case ARM::VLD2DUPd16wb_fixed:
3533    case ARM::VLD2DUPd32wb_fixed:
3534    case ARM::VLD2DUPd8wb_register:
3535    case ARM::VLD2DUPd16wb_register:
3536    case ARM::VLD2DUPd32wb_register:
3537    case ARM::VLD4DUPd8Pseudo:
3538    case ARM::VLD4DUPd16Pseudo:
3539    case ARM::VLD4DUPd32Pseudo:
3540    case ARM::VLD4DUPd8Pseudo_UPD:
3541    case ARM::VLD4DUPd16Pseudo_UPD:
3542    case ARM::VLD4DUPd32Pseudo_UPD:
3543    case ARM::VLD1LNq8Pseudo:
3544    case ARM::VLD1LNq16Pseudo:
3545    case ARM::VLD1LNq32Pseudo:
3546    case ARM::VLD1LNq8Pseudo_UPD:
3547    case ARM::VLD1LNq16Pseudo_UPD:
3548    case ARM::VLD1LNq32Pseudo_UPD:
3549    case ARM::VLD2LNd8Pseudo:
3550    case ARM::VLD2LNd16Pseudo:
3551    case ARM::VLD2LNd32Pseudo:
3552    case ARM::VLD2LNq16Pseudo:
3553    case ARM::VLD2LNq32Pseudo:
3554    case ARM::VLD2LNd8Pseudo_UPD:
3555    case ARM::VLD2LNd16Pseudo_UPD:
3556    case ARM::VLD2LNd32Pseudo_UPD:
3557    case ARM::VLD2LNq16Pseudo_UPD:
3558    case ARM::VLD2LNq32Pseudo_UPD:
3559    case ARM::VLD4LNd8Pseudo:
3560    case ARM::VLD4LNd16Pseudo:
3561    case ARM::VLD4LNd32Pseudo:
3562    case ARM::VLD4LNq16Pseudo:
3563    case ARM::VLD4LNq32Pseudo:
3564    case ARM::VLD4LNd8Pseudo_UPD:
3565    case ARM::VLD4LNd16Pseudo_UPD:
3566    case ARM::VLD4LNd32Pseudo_UPD:
3567    case ARM::VLD4LNq16Pseudo_UPD:
3568    case ARM::VLD4LNq32Pseudo_UPD:
3569      // If the address is not 64-bit aligned, the latencies of these
3570      // instructions increases by one.
3571      ++Latency;
3572      break;
3573    }
3574
3575  return Latency;
3576}
3577
3578unsigned ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData,
3579                                           const MachineInstr *MI,
3580                                           unsigned *PredCost) const {
3581  if (MI->isCopyLike() || MI->isInsertSubreg() ||
3582      MI->isRegSequence() || MI->isImplicitDef())
3583    return 1;
3584
3585  // An instruction scheduler typically runs on unbundled instructions, however
3586  // other passes may query the latency of a bundled instruction.
3587  if (MI->isBundle()) {
3588    unsigned Latency = 0;
3589    MachineBasicBlock::const_instr_iterator I = MI;
3590    MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
3591    while (++I != E && I->isInsideBundle()) {
3592      if (I->getOpcode() != ARM::t2IT)
3593        Latency += getInstrLatency(ItinData, I, PredCost);
3594    }
3595    return Latency;
3596  }
3597
3598  const MCInstrDesc &MCID = MI->getDesc();
3599  if (PredCost && (MCID.isCall() || MCID.hasImplicitDefOfPhysReg(ARM::CPSR))) {
3600    // When predicated, CPSR is an additional source operand for CPSR updating
3601    // instructions, this apparently increases their latencies.
3602    *PredCost = 1;
3603  }
3604  // Be sure to call getStageLatency for an empty itinerary in case it has a
3605  // valid MinLatency property.
3606  if (!ItinData)
3607    return MI->mayLoad() ? 3 : 1;
3608
3609  unsigned Class = MCID.getSchedClass();
3610
3611  // For instructions with variable uops, use uops as latency.
3612  if (!ItinData->isEmpty() && ItinData->getNumMicroOps(Class) < 0)
3613    return getNumMicroOps(ItinData, MI);
3614
3615  // For the common case, fall back on the itinerary's latency.
3616  unsigned Latency = ItinData->getStageLatency(Class);
3617
3618  // Adjust for dynamic def-side opcode variants not captured by the itinerary.
3619  unsigned DefAlign = MI->hasOneMemOperand()
3620    ? (*MI->memoperands_begin())->getAlignment() : 0;
3621  int Adj = adjustDefLatency(Subtarget, MI, &MCID, DefAlign);
3622  if (Adj >= 0 || (int)Latency > -Adj) {
3623    return Latency + Adj;
3624  }
3625  return Latency;
3626}
3627
3628int ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData,
3629                                      SDNode *Node) const {
3630  if (!Node->isMachineOpcode())
3631    return 1;
3632
3633  if (!ItinData || ItinData->isEmpty())
3634    return 1;
3635
3636  unsigned Opcode = Node->getMachineOpcode();
3637  switch (Opcode) {
3638  default:
3639    return ItinData->getStageLatency(get(Opcode).getSchedClass());
3640  case ARM::VLDMQIA:
3641  case ARM::VSTMQIA:
3642    return 2;
3643  }
3644}
3645
3646bool ARMBaseInstrInfo::
3647hasHighOperandLatency(const InstrItineraryData *ItinData,
3648                      const MachineRegisterInfo *MRI,
3649                      const MachineInstr *DefMI, unsigned DefIdx,
3650                      const MachineInstr *UseMI, unsigned UseIdx) const {
3651  unsigned DDomain = DefMI->getDesc().TSFlags & ARMII::DomainMask;
3652  unsigned UDomain = UseMI->getDesc().TSFlags & ARMII::DomainMask;
3653  if (Subtarget.isCortexA8() &&
3654      (DDomain == ARMII::DomainVFP || UDomain == ARMII::DomainVFP))
3655    // CortexA8 VFP instructions are not pipelined.
3656    return true;
3657
3658  // Hoist VFP / NEON instructions with 4 or higher latency.
3659  int Latency = computeOperandLatency(ItinData, DefMI, DefIdx, UseMI, UseIdx,
3660                                      /*FindMin=*/false);
3661  if (Latency < 0)
3662    Latency = getInstrLatency(ItinData, DefMI);
3663  if (Latency <= 3)
3664    return false;
3665  return DDomain == ARMII::DomainVFP || DDomain == ARMII::DomainNEON ||
3666         UDomain == ARMII::DomainVFP || UDomain == ARMII::DomainNEON;
3667}
3668
3669bool ARMBaseInstrInfo::
3670hasLowDefLatency(const InstrItineraryData *ItinData,
3671                 const MachineInstr *DefMI, unsigned DefIdx) const {
3672  if (!ItinData || ItinData->isEmpty())
3673    return false;
3674
3675  unsigned DDomain = DefMI->getDesc().TSFlags & ARMII::DomainMask;
3676  if (DDomain == ARMII::DomainGeneral) {
3677    unsigned DefClass = DefMI->getDesc().getSchedClass();
3678    int DefCycle = ItinData->getOperandCycle(DefClass, DefIdx);
3679    return (DefCycle != -1 && DefCycle <= 2);
3680  }
3681  return false;
3682}
3683
3684bool ARMBaseInstrInfo::verifyInstruction(const MachineInstr *MI,
3685                                         StringRef &ErrInfo) const {
3686  if (convertAddSubFlagsOpcode(MI->getOpcode())) {
3687    ErrInfo = "Pseudo flag setting opcodes only exist in Selection DAG";
3688    return false;
3689  }
3690  return true;
3691}
3692
3693bool
3694ARMBaseInstrInfo::isFpMLxInstruction(unsigned Opcode, unsigned &MulOpc,
3695                                     unsigned &AddSubOpc,
3696                                     bool &NegAcc, bool &HasLane) const {
3697  DenseMap<unsigned, unsigned>::const_iterator I = MLxEntryMap.find(Opcode);
3698  if (I == MLxEntryMap.end())
3699    return false;
3700
3701  const ARM_MLxEntry &Entry = ARM_MLxTable[I->second];
3702  MulOpc = Entry.MulOpc;
3703  AddSubOpc = Entry.AddSubOpc;
3704  NegAcc = Entry.NegAcc;
3705  HasLane = Entry.HasLane;
3706  return true;
3707}
3708
3709//===----------------------------------------------------------------------===//
3710// Execution domains.
3711//===----------------------------------------------------------------------===//
3712//
3713// Some instructions go down the NEON pipeline, some go down the VFP pipeline,
3714// and some can go down both.  The vmov instructions go down the VFP pipeline,
3715// but they can be changed to vorr equivalents that are executed by the NEON
3716// pipeline.
3717//
3718// We use the following execution domain numbering:
3719//
3720enum ARMExeDomain {
3721  ExeGeneric = 0,
3722  ExeVFP = 1,
3723  ExeNEON = 2
3724};
3725//
3726// Also see ARMInstrFormats.td and Domain* enums in ARMBaseInfo.h
3727//
3728std::pair<uint16_t, uint16_t>
3729ARMBaseInstrInfo::getExecutionDomain(const MachineInstr *MI) const {
3730  // VMOVD, VMOVRS and VMOVSR are VFP instructions, but can be changed to NEON
3731  // if they are not predicated.
3732  if (MI->getOpcode() == ARM::VMOVD && !isPredicated(MI))
3733    return std::make_pair(ExeVFP, (1<<ExeVFP) | (1<<ExeNEON));
3734
3735  // A9-like cores are particularly picky about mixing the two and want these
3736  // converted.
3737  if (Subtarget.isLikeA9() && !isPredicated(MI) &&
3738      (MI->getOpcode() == ARM::VMOVRS ||
3739       MI->getOpcode() == ARM::VMOVSR ||
3740       MI->getOpcode() == ARM::VMOVS))
3741    return std::make_pair(ExeVFP, (1<<ExeVFP) | (1<<ExeNEON));
3742
3743  // No other instructions can be swizzled, so just determine their domain.
3744  unsigned Domain = MI->getDesc().TSFlags & ARMII::DomainMask;
3745
3746  if (Domain & ARMII::DomainNEON)
3747    return std::make_pair(ExeNEON, 0);
3748
3749  // Certain instructions can go either way on Cortex-A8.
3750  // Treat them as NEON instructions.
3751  if ((Domain & ARMII::DomainNEONA8) && Subtarget.isCortexA8())
3752    return std::make_pair(ExeNEON, 0);
3753
3754  if (Domain & ARMII::DomainVFP)
3755    return std::make_pair(ExeVFP, 0);
3756
3757  return std::make_pair(ExeGeneric, 0);
3758}
3759
3760static unsigned getCorrespondingDRegAndLane(const TargetRegisterInfo *TRI,
3761                                            unsigned SReg, unsigned &Lane) {
3762  unsigned DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_0, &ARM::DPRRegClass);
3763  Lane = 0;
3764
3765  if (DReg != ARM::NoRegister)
3766   return DReg;
3767
3768  Lane = 1;
3769  DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_1, &ARM::DPRRegClass);
3770
3771  assert(DReg && "S-register with no D super-register?");
3772  return DReg;
3773}
3774
3775/// getImplicitSPRUseForDPRUse - Given a use of a DPR register and lane,
3776/// set ImplicitSReg to a register number that must be marked as implicit-use or
3777/// zero if no register needs to be defined as implicit-use.
3778///
3779/// If the function cannot determine if an SPR should be marked implicit use or
3780/// not, it returns false.
3781///
3782/// This function handles cases where an instruction is being modified from taking
3783/// an SPR to a DPR[Lane]. A use of the DPR is being added, which may conflict
3784/// with an earlier def of an SPR corresponding to DPR[Lane^1] (i.e. the other
3785/// lane of the DPR).
3786///
3787/// If the other SPR is defined, an implicit-use of it should be added. Else,
3788/// (including the case where the DPR itself is defined), it should not.
3789///
3790static bool getImplicitSPRUseForDPRUse(const TargetRegisterInfo *TRI,
3791                                       MachineInstr *MI,
3792                                       unsigned DReg, unsigned Lane,
3793                                       unsigned &ImplicitSReg) {
3794  // If the DPR is defined or used already, the other SPR lane will be chained
3795  // correctly, so there is nothing to be done.
3796  if (MI->definesRegister(DReg, TRI) || MI->readsRegister(DReg, TRI)) {
3797    ImplicitSReg = 0;
3798    return true;
3799  }
3800
3801  // Otherwise we need to go searching to see if the SPR is set explicitly.
3802  ImplicitSReg = TRI->getSubReg(DReg,
3803                                (Lane & 1) ? ARM::ssub_0 : ARM::ssub_1);
3804  MachineBasicBlock::LivenessQueryResult LQR =
3805    MI->getParent()->computeRegisterLiveness(TRI, ImplicitSReg, MI);
3806
3807  if (LQR == MachineBasicBlock::LQR_Live)
3808    return true;
3809  else if (LQR == MachineBasicBlock::LQR_Unknown)
3810    return false;
3811
3812  // If the register is known not to be live, there is no need to add an
3813  // implicit-use.
3814  ImplicitSReg = 0;
3815  return true;
3816}
3817
3818void
3819ARMBaseInstrInfo::setExecutionDomain(MachineInstr *MI, unsigned Domain) const {
3820  unsigned DstReg, SrcReg, DReg;
3821  unsigned Lane;
3822  MachineInstrBuilder MIB(MI);
3823  const TargetRegisterInfo *TRI = &getRegisterInfo();
3824  switch (MI->getOpcode()) {
3825    default:
3826      llvm_unreachable("cannot handle opcode!");
3827      break;
3828    case ARM::VMOVD:
3829      if (Domain != ExeNEON)
3830        break;
3831
3832      // Zap the predicate operands.
3833      assert(!isPredicated(MI) && "Cannot predicate a VORRd");
3834
3835      // Source instruction is %DDst = VMOVD %DSrc, 14, %noreg (; implicits)
3836      DstReg = MI->getOperand(0).getReg();
3837      SrcReg = MI->getOperand(1).getReg();
3838
3839      for (unsigned i = MI->getDesc().getNumOperands(); i; --i)
3840        MI->RemoveOperand(i-1);
3841
3842      // Change to a %DDst = VORRd %DSrc, %DSrc, 14, %noreg (; implicits)
3843      MI->setDesc(get(ARM::VORRd));
3844      AddDefaultPred(MIB.addReg(DstReg, RegState::Define)
3845                        .addReg(SrcReg)
3846                        .addReg(SrcReg));
3847      break;
3848    case ARM::VMOVRS:
3849      if (Domain != ExeNEON)
3850        break;
3851      assert(!isPredicated(MI) && "Cannot predicate a VGETLN");
3852
3853      // Source instruction is %RDst = VMOVRS %SSrc, 14, %noreg (; implicits)
3854      DstReg = MI->getOperand(0).getReg();
3855      SrcReg = MI->getOperand(1).getReg();
3856
3857      for (unsigned i = MI->getDesc().getNumOperands(); i; --i)
3858        MI->RemoveOperand(i-1);
3859
3860      DReg = getCorrespondingDRegAndLane(TRI, SrcReg, Lane);
3861
3862      // Convert to %RDst = VGETLNi32 %DSrc, Lane, 14, %noreg (; imps)
3863      // Note that DSrc has been widened and the other lane may be undef, which
3864      // contaminates the entire register.
3865      MI->setDesc(get(ARM::VGETLNi32));
3866      AddDefaultPred(MIB.addReg(DstReg, RegState::Define)
3867                        .addReg(DReg, RegState::Undef)
3868                        .addImm(Lane));
3869
3870      // The old source should be an implicit use, otherwise we might think it
3871      // was dead before here.
3872      MIB.addReg(SrcReg, RegState::Implicit);
3873      break;
3874    case ARM::VMOVSR: {
3875      if (Domain != ExeNEON)
3876        break;
3877      assert(!isPredicated(MI) && "Cannot predicate a VSETLN");
3878
3879      // Source instruction is %SDst = VMOVSR %RSrc, 14, %noreg (; implicits)
3880      DstReg = MI->getOperand(0).getReg();
3881      SrcReg = MI->getOperand(1).getReg();
3882
3883      DReg = getCorrespondingDRegAndLane(TRI, DstReg, Lane);
3884
3885      unsigned ImplicitSReg;
3886      if (!getImplicitSPRUseForDPRUse(TRI, MI, DReg, Lane, ImplicitSReg))
3887        break;
3888
3889      for (unsigned i = MI->getDesc().getNumOperands(); i; --i)
3890        MI->RemoveOperand(i-1);
3891
3892      // Convert to %DDst = VSETLNi32 %DDst, %RSrc, Lane, 14, %noreg (; imps)
3893      // Again DDst may be undefined at the beginning of this instruction.
3894      MI->setDesc(get(ARM::VSETLNi32));
3895      MIB.addReg(DReg, RegState::Define)
3896         .addReg(DReg, getUndefRegState(!MI->readsRegister(DReg, TRI)))
3897         .addReg(SrcReg)
3898         .addImm(Lane);
3899      AddDefaultPred(MIB);
3900
3901      // The narrower destination must be marked as set to keep previous chains
3902      // in place.
3903      MIB.addReg(DstReg, RegState::Define | RegState::Implicit);
3904      if (ImplicitSReg != 0)
3905        MIB.addReg(ImplicitSReg, RegState::Implicit);
3906      break;
3907    }
3908    case ARM::VMOVS: {
3909      if (Domain != ExeNEON)
3910        break;
3911
3912      // Source instruction is %SDst = VMOVS %SSrc, 14, %noreg (; implicits)
3913      DstReg = MI->getOperand(0).getReg();
3914      SrcReg = MI->getOperand(1).getReg();
3915
3916      unsigned DstLane = 0, SrcLane = 0, DDst, DSrc;
3917      DDst = getCorrespondingDRegAndLane(TRI, DstReg, DstLane);
3918      DSrc = getCorrespondingDRegAndLane(TRI, SrcReg, SrcLane);
3919
3920      unsigned ImplicitSReg;
3921      if (!getImplicitSPRUseForDPRUse(TRI, MI, DSrc, SrcLane, ImplicitSReg))
3922        break;
3923
3924      for (unsigned i = MI->getDesc().getNumOperands(); i; --i)
3925        MI->RemoveOperand(i-1);
3926
3927      if (DSrc == DDst) {
3928        // Destination can be:
3929        //     %DDst = VDUPLN32d %DDst, Lane, 14, %noreg (; implicits)
3930        MI->setDesc(get(ARM::VDUPLN32d));
3931        MIB.addReg(DDst, RegState::Define)
3932           .addReg(DDst, getUndefRegState(!MI->readsRegister(DDst, TRI)))
3933           .addImm(SrcLane);
3934        AddDefaultPred(MIB);
3935
3936        // Neither the source or the destination are naturally represented any
3937        // more, so add them in manually.
3938        MIB.addReg(DstReg, RegState::Implicit | RegState::Define);
3939        MIB.addReg(SrcReg, RegState::Implicit);
3940        if (ImplicitSReg != 0)
3941          MIB.addReg(ImplicitSReg, RegState::Implicit);
3942        break;
3943      }
3944
3945      // In general there's no single instruction that can perform an S <-> S
3946      // move in NEON space, but a pair of VEXT instructions *can* do the
3947      // job. It turns out that the VEXTs needed will only use DSrc once, with
3948      // the position based purely on the combination of lane-0 and lane-1
3949      // involved. For example
3950      //     vmov s0, s2 -> vext.32 d0, d0, d1, #1  vext.32 d0, d0, d0, #1
3951      //     vmov s1, s3 -> vext.32 d0, d1, d0, #1  vext.32 d0, d0, d0, #1
3952      //     vmov s0, s3 -> vext.32 d0, d0, d0, #1  vext.32 d0, d1, d0, #1
3953      //     vmov s1, s2 -> vext.32 d0, d0, d0, #1  vext.32 d0, d0, d1, #1
3954      //
3955      // Pattern of the MachineInstrs is:
3956      //     %DDst = VEXTd32 %DSrc1, %DSrc2, Lane, 14, %noreg (;implicits)
3957      MachineInstrBuilder NewMIB;
3958      NewMIB = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(),
3959                       get(ARM::VEXTd32), DDst);
3960
3961      // On the first instruction, both DSrc and DDst may be <undef> if present.
3962      // Specifically when the original instruction didn't have them as an
3963      // <imp-use>.
3964      unsigned CurReg = SrcLane == 1 && DstLane == 1 ? DSrc : DDst;
3965      bool CurUndef = !MI->readsRegister(CurReg, TRI);
3966      NewMIB.addReg(CurReg, getUndefRegState(CurUndef));
3967
3968      CurReg = SrcLane == 0 && DstLane == 0 ? DSrc : DDst;
3969      CurUndef = !MI->readsRegister(CurReg, TRI);
3970      NewMIB.addReg(CurReg, getUndefRegState(CurUndef));
3971
3972      NewMIB.addImm(1);
3973      AddDefaultPred(NewMIB);
3974
3975      if (SrcLane == DstLane)
3976        NewMIB.addReg(SrcReg, RegState::Implicit);
3977
3978      MI->setDesc(get(ARM::VEXTd32));
3979      MIB.addReg(DDst, RegState::Define);
3980
3981      // On the second instruction, DDst has definitely been defined above, so
3982      // it is not <undef>. DSrc, if present, can be <undef> as above.
3983      CurReg = SrcLane == 1 && DstLane == 0 ? DSrc : DDst;
3984      CurUndef = CurReg == DSrc && !MI->readsRegister(CurReg, TRI);
3985      MIB.addReg(CurReg, getUndefRegState(CurUndef));
3986
3987      CurReg = SrcLane == 0 && DstLane == 1 ? DSrc : DDst;
3988      CurUndef = CurReg == DSrc && !MI->readsRegister(CurReg, TRI);
3989      MIB.addReg(CurReg, getUndefRegState(CurUndef));
3990
3991      MIB.addImm(1);
3992      AddDefaultPred(MIB);
3993
3994      if (SrcLane != DstLane)
3995        MIB.addReg(SrcReg, RegState::Implicit);
3996
3997      // As before, the original destination is no longer represented, add it
3998      // implicitly.
3999      MIB.addReg(DstReg, RegState::Define | RegState::Implicit);
4000      if (ImplicitSReg != 0)
4001        MIB.addReg(ImplicitSReg, RegState::Implicit);
4002      break;
4003    }
4004  }
4005
4006}
4007
4008//===----------------------------------------------------------------------===//
4009// Partial register updates
4010//===----------------------------------------------------------------------===//
4011//
4012// Swift renames NEON registers with 64-bit granularity.  That means any
4013// instruction writing an S-reg implicitly reads the containing D-reg.  The
4014// problem is mostly avoided by translating f32 operations to v2f32 operations
4015// on D-registers, but f32 loads are still a problem.
4016//
4017// These instructions can load an f32 into a NEON register:
4018//
4019// VLDRS - Only writes S, partial D update.
4020// VLD1LNd32 - Writes all D-regs, explicit partial D update, 2 uops.
4021// VLD1DUPd32 - Writes all D-regs, no partial reg update, 2 uops.
4022//
4023// FCONSTD can be used as a dependency-breaking instruction.
4024
4025
4026unsigned ARMBaseInstrInfo::
4027getPartialRegUpdateClearance(const MachineInstr *MI,
4028                             unsigned OpNum,
4029                             const TargetRegisterInfo *TRI) const {
4030  // Only Swift has partial register update problems.
4031  if (!SwiftPartialUpdateClearance || !Subtarget.isSwift())
4032    return 0;
4033
4034  assert(TRI && "Need TRI instance");
4035
4036  const MachineOperand &MO = MI->getOperand(OpNum);
4037  if (MO.readsReg())
4038    return 0;
4039  unsigned Reg = MO.getReg();
4040  int UseOp = -1;
4041
4042  switch(MI->getOpcode()) {
4043    // Normal instructions writing only an S-register.
4044  case ARM::VLDRS:
4045  case ARM::FCONSTS:
4046  case ARM::VMOVSR:
4047    // rdar://problem/8791586
4048  case ARM::VMOVv8i8:
4049  case ARM::VMOVv4i16:
4050  case ARM::VMOVv2i32:
4051  case ARM::VMOVv2f32:
4052  case ARM::VMOVv1i64:
4053    UseOp = MI->findRegisterUseOperandIdx(Reg, false, TRI);
4054    break;
4055
4056    // Explicitly reads the dependency.
4057  case ARM::VLD1LNd32:
4058    UseOp = 1;
4059    break;
4060  default:
4061    return 0;
4062  }
4063
4064  // If this instruction actually reads a value from Reg, there is no unwanted
4065  // dependency.
4066  if (UseOp != -1 && MI->getOperand(UseOp).readsReg())
4067    return 0;
4068
4069  // We must be able to clobber the whole D-reg.
4070  if (TargetRegisterInfo::isVirtualRegister(Reg)) {
4071    // Virtual register must be a foo:ssub_0<def,undef> operand.
4072    if (!MO.getSubReg() || MI->readsVirtualRegister(Reg))
4073      return 0;
4074  } else if (ARM::SPRRegClass.contains(Reg)) {
4075    // Physical register: MI must define the full D-reg.
4076    unsigned DReg = TRI->getMatchingSuperReg(Reg, ARM::ssub_0,
4077                                             &ARM::DPRRegClass);
4078    if (!DReg || !MI->definesRegister(DReg, TRI))
4079      return 0;
4080  }
4081
4082  // MI has an unwanted D-register dependency.
4083  // Avoid defs in the previous N instructrions.
4084  return SwiftPartialUpdateClearance;
4085}
4086
4087// Break a partial register dependency after getPartialRegUpdateClearance
4088// returned non-zero.
4089void ARMBaseInstrInfo::
4090breakPartialRegDependency(MachineBasicBlock::iterator MI,
4091                          unsigned OpNum,
4092                          const TargetRegisterInfo *TRI) const {
4093  assert(MI && OpNum < MI->getDesc().getNumDefs() && "OpNum is not a def");
4094  assert(TRI && "Need TRI instance");
4095
4096  const MachineOperand &MO = MI->getOperand(OpNum);
4097  unsigned Reg = MO.getReg();
4098  assert(TargetRegisterInfo::isPhysicalRegister(Reg) &&
4099         "Can't break virtual register dependencies.");
4100  unsigned DReg = Reg;
4101
4102  // If MI defines an S-reg, find the corresponding D super-register.
4103  if (ARM::SPRRegClass.contains(Reg)) {
4104    DReg = ARM::D0 + (Reg - ARM::S0) / 2;
4105    assert(TRI->isSuperRegister(Reg, DReg) && "Register enums broken");
4106  }
4107
4108  assert(ARM::DPRRegClass.contains(DReg) && "Can only break D-reg deps");
4109  assert(MI->definesRegister(DReg, TRI) && "MI doesn't clobber full D-reg");
4110
4111  // FIXME: In some cases, VLDRS can be changed to a VLD1DUPd32 which defines
4112  // the full D-register by loading the same value to both lanes.  The
4113  // instruction is micro-coded with 2 uops, so don't do this until we can
4114  // properly schedule micro-coded instuctions.  The dispatcher stalls cause
4115  // too big regressions.
4116
4117  // Insert the dependency-breaking FCONSTD before MI.
4118  // 96 is the encoding of 0.5, but the actual value doesn't matter here.
4119  AddDefaultPred(BuildMI(*MI->getParent(), MI, MI->getDebugLoc(),
4120                         get(ARM::FCONSTD), DReg).addImm(96));
4121  MI->addRegisterKilled(DReg, TRI, true);
4122}
4123
4124bool ARMBaseInstrInfo::hasNOP() const {
4125  return (Subtarget.getFeatureBits() & ARM::HasV6T2Ops) != 0;
4126}
4127