MachineInstr.cpp revision 0d7585839540abb9ab661a741dc3e0c2c860bceb
1//===-- lib/CodeGen/MachineInstr.cpp --------------------------------------===//
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// Methods common to all machine instructions.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/CodeGen/MachineInstr.h"
15#include "llvm/Constants.h"
16#include "llvm/DebugInfo.h"
17#include "llvm/Function.h"
18#include "llvm/InlineAsm.h"
19#include "llvm/LLVMContext.h"
20#include "llvm/Metadata.h"
21#include "llvm/Module.h"
22#include "llvm/Type.h"
23#include "llvm/Value.h"
24#include "llvm/Assembly/Writer.h"
25#include "llvm/CodeGen/MachineConstantPool.h"
26#include "llvm/CodeGen/MachineFunction.h"
27#include "llvm/CodeGen/MachineMemOperand.h"
28#include "llvm/CodeGen/MachineModuleInfo.h"
29#include "llvm/CodeGen/MachineRegisterInfo.h"
30#include "llvm/CodeGen/PseudoSourceValue.h"
31#include "llvm/MC/MCInstrDesc.h"
32#include "llvm/MC/MCSymbol.h"
33#include "llvm/Target/TargetMachine.h"
34#include "llvm/Target/TargetInstrInfo.h"
35#include "llvm/Target/TargetRegisterInfo.h"
36#include "llvm/Analysis/AliasAnalysis.h"
37#include "llvm/Support/Debug.h"
38#include "llvm/Support/ErrorHandling.h"
39#include "llvm/Support/LeakDetector.h"
40#include "llvm/Support/MathExtras.h"
41#include "llvm/Support/raw_ostream.h"
42#include "llvm/ADT/FoldingSet.h"
43#include "llvm/ADT/Hashing.h"
44using namespace llvm;
45
46//===----------------------------------------------------------------------===//
47// MachineOperand Implementation
48//===----------------------------------------------------------------------===//
49
50void MachineOperand::setReg(unsigned Reg) {
51  if (getReg() == Reg) return; // No change.
52
53  // Otherwise, we have to change the register.  If this operand is embedded
54  // into a machine function, we need to update the old and new register's
55  // use/def lists.
56  if (MachineInstr *MI = getParent())
57    if (MachineBasicBlock *MBB = MI->getParent())
58      if (MachineFunction *MF = MBB->getParent()) {
59        MachineRegisterInfo &MRI = MF->getRegInfo();
60        MRI.removeRegOperandFromUseList(this);
61        SmallContents.RegNo = Reg;
62        MRI.addRegOperandToUseList(this);
63        return;
64      }
65
66  // Otherwise, just change the register, no problem.  :)
67  SmallContents.RegNo = Reg;
68}
69
70void MachineOperand::substVirtReg(unsigned Reg, unsigned SubIdx,
71                                  const TargetRegisterInfo &TRI) {
72  assert(TargetRegisterInfo::isVirtualRegister(Reg));
73  if (SubIdx && getSubReg())
74    SubIdx = TRI.composeSubRegIndices(SubIdx, getSubReg());
75  setReg(Reg);
76  if (SubIdx)
77    setSubReg(SubIdx);
78}
79
80void MachineOperand::substPhysReg(unsigned Reg, const TargetRegisterInfo &TRI) {
81  assert(TargetRegisterInfo::isPhysicalRegister(Reg));
82  if (getSubReg()) {
83    Reg = TRI.getSubReg(Reg, getSubReg());
84    // Note that getSubReg() may return 0 if the sub-register doesn't exist.
85    // That won't happen in legal code.
86    setSubReg(0);
87  }
88  setReg(Reg);
89}
90
91/// Change a def to a use, or a use to a def.
92void MachineOperand::setIsDef(bool Val) {
93  assert(isReg() && "Wrong MachineOperand accessor");
94  assert((!Val || !isDebug()) && "Marking a debug operation as def");
95  if (IsDef == Val)
96    return;
97  // MRI may keep uses and defs in different list positions.
98  if (MachineInstr *MI = getParent())
99    if (MachineBasicBlock *MBB = MI->getParent())
100      if (MachineFunction *MF = MBB->getParent()) {
101        MachineRegisterInfo &MRI = MF->getRegInfo();
102        MRI.removeRegOperandFromUseList(this);
103        IsDef = Val;
104        MRI.addRegOperandToUseList(this);
105        return;
106      }
107  IsDef = Val;
108}
109
110/// ChangeToImmediate - Replace this operand with a new immediate operand of
111/// the specified value.  If an operand is known to be an immediate already,
112/// the setImm method should be used.
113void MachineOperand::ChangeToImmediate(int64_t ImmVal) {
114  assert((!isReg() || !isTied()) && "Cannot change a tied operand into an imm");
115  // If this operand is currently a register operand, and if this is in a
116  // function, deregister the operand from the register's use/def list.
117  if (isReg() && isOnRegUseList())
118    if (MachineInstr *MI = getParent())
119      if (MachineBasicBlock *MBB = MI->getParent())
120        if (MachineFunction *MF = MBB->getParent())
121          MF->getRegInfo().removeRegOperandFromUseList(this);
122
123  OpKind = MO_Immediate;
124  Contents.ImmVal = ImmVal;
125}
126
127/// ChangeToRegister - Replace this operand with a new register operand of
128/// the specified value.  If an operand is known to be an register already,
129/// the setReg method should be used.
130void MachineOperand::ChangeToRegister(unsigned Reg, bool isDef, bool isImp,
131                                      bool isKill, bool isDead, bool isUndef,
132                                      bool isDebug) {
133  MachineRegisterInfo *RegInfo = 0;
134  if (MachineInstr *MI = getParent())
135    if (MachineBasicBlock *MBB = MI->getParent())
136      if (MachineFunction *MF = MBB->getParent())
137        RegInfo = &MF->getRegInfo();
138  // If this operand is already a register operand, remove it from the
139  // register's use/def lists.
140  bool WasReg = isReg();
141  if (RegInfo && WasReg)
142    RegInfo->removeRegOperandFromUseList(this);
143
144  // Change this to a register and set the reg#.
145  OpKind = MO_Register;
146  SmallContents.RegNo = Reg;
147  SubReg = 0;
148  IsDef = isDef;
149  IsImp = isImp;
150  IsKill = isKill;
151  IsDead = isDead;
152  IsUndef = isUndef;
153  IsInternalRead = false;
154  IsEarlyClobber = false;
155  IsDebug = isDebug;
156  // Ensure isOnRegUseList() returns false.
157  Contents.Reg.Prev = 0;
158  // Preserve the tie bit when the operand was already a register.
159  if (!WasReg)
160    IsTied = false;
161
162  // If this operand is embedded in a function, add the operand to the
163  // register's use/def list.
164  if (RegInfo)
165    RegInfo->addRegOperandToUseList(this);
166}
167
168/// isIdenticalTo - Return true if this operand is identical to the specified
169/// operand. Note that this should stay in sync with the hash_value overload
170/// below.
171bool MachineOperand::isIdenticalTo(const MachineOperand &Other) const {
172  if (getType() != Other.getType() ||
173      getTargetFlags() != Other.getTargetFlags())
174    return false;
175
176  switch (getType()) {
177  case MachineOperand::MO_Register:
178    return getReg() == Other.getReg() && isDef() == Other.isDef() &&
179           getSubReg() == Other.getSubReg();
180  case MachineOperand::MO_Immediate:
181    return getImm() == Other.getImm();
182  case MachineOperand::MO_CImmediate:
183    return getCImm() == Other.getCImm();
184  case MachineOperand::MO_FPImmediate:
185    return getFPImm() == Other.getFPImm();
186  case MachineOperand::MO_MachineBasicBlock:
187    return getMBB() == Other.getMBB();
188  case MachineOperand::MO_FrameIndex:
189    return getIndex() == Other.getIndex();
190  case MachineOperand::MO_ConstantPoolIndex:
191  case MachineOperand::MO_TargetIndex:
192    return getIndex() == Other.getIndex() && getOffset() == Other.getOffset();
193  case MachineOperand::MO_JumpTableIndex:
194    return getIndex() == Other.getIndex();
195  case MachineOperand::MO_GlobalAddress:
196    return getGlobal() == Other.getGlobal() && getOffset() == Other.getOffset();
197  case MachineOperand::MO_ExternalSymbol:
198    return !strcmp(getSymbolName(), Other.getSymbolName()) &&
199           getOffset() == Other.getOffset();
200  case MachineOperand::MO_BlockAddress:
201    return getBlockAddress() == Other.getBlockAddress();
202  case MO_RegisterMask:
203    return getRegMask() == Other.getRegMask();
204  case MachineOperand::MO_MCSymbol:
205    return getMCSymbol() == Other.getMCSymbol();
206  case MachineOperand::MO_Metadata:
207    return getMetadata() == Other.getMetadata();
208  }
209  llvm_unreachable("Invalid machine operand type");
210}
211
212// Note: this must stay exactly in sync with isIdenticalTo above.
213hash_code llvm::hash_value(const MachineOperand &MO) {
214  switch (MO.getType()) {
215  case MachineOperand::MO_Register:
216    // Register operands don't have target flags.
217    return hash_combine(MO.getType(), MO.getReg(), MO.getSubReg(), MO.isDef());
218  case MachineOperand::MO_Immediate:
219    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getImm());
220  case MachineOperand::MO_CImmediate:
221    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getCImm());
222  case MachineOperand::MO_FPImmediate:
223    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getFPImm());
224  case MachineOperand::MO_MachineBasicBlock:
225    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getMBB());
226  case MachineOperand::MO_FrameIndex:
227    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIndex());
228  case MachineOperand::MO_ConstantPoolIndex:
229  case MachineOperand::MO_TargetIndex:
230    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIndex(),
231                        MO.getOffset());
232  case MachineOperand::MO_JumpTableIndex:
233    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIndex());
234  case MachineOperand::MO_ExternalSymbol:
235    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getOffset(),
236                        MO.getSymbolName());
237  case MachineOperand::MO_GlobalAddress:
238    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getGlobal(),
239                        MO.getOffset());
240  case MachineOperand::MO_BlockAddress:
241    return hash_combine(MO.getType(), MO.getTargetFlags(),
242                        MO.getBlockAddress());
243  case MachineOperand::MO_RegisterMask:
244    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getRegMask());
245  case MachineOperand::MO_Metadata:
246    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getMetadata());
247  case MachineOperand::MO_MCSymbol:
248    return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getMCSymbol());
249  }
250  llvm_unreachable("Invalid machine operand type");
251}
252
253/// print - Print the specified machine operand.
254///
255void MachineOperand::print(raw_ostream &OS, const TargetMachine *TM) const {
256  // If the instruction is embedded into a basic block, we can find the
257  // target info for the instruction.
258  if (!TM)
259    if (const MachineInstr *MI = getParent())
260      if (const MachineBasicBlock *MBB = MI->getParent())
261        if (const MachineFunction *MF = MBB->getParent())
262          TM = &MF->getTarget();
263  const TargetRegisterInfo *TRI = TM ? TM->getRegisterInfo() : 0;
264
265  switch (getType()) {
266  case MachineOperand::MO_Register:
267    OS << PrintReg(getReg(), TRI, getSubReg());
268
269    if (isDef() || isKill() || isDead() || isImplicit() || isUndef() ||
270        isInternalRead() || isEarlyClobber() || isTied()) {
271      OS << '<';
272      bool NeedComma = false;
273      if (isDef()) {
274        if (NeedComma) OS << ',';
275        if (isEarlyClobber())
276          OS << "earlyclobber,";
277        if (isImplicit())
278          OS << "imp-";
279        OS << "def";
280        NeedComma = true;
281        // <def,read-undef> only makes sense when getSubReg() is set.
282        // Don't clutter the output otherwise.
283        if (isUndef() && getSubReg())
284          OS << ",read-undef";
285      } else if (isImplicit()) {
286          OS << "imp-use";
287          NeedComma = true;
288      }
289
290      if (isKill()) {
291        if (NeedComma) OS << ',';
292        OS << "kill";
293        NeedComma = true;
294      }
295      if (isDead()) {
296        if (NeedComma) OS << ',';
297        OS << "dead";
298        NeedComma = true;
299      }
300      if (isUndef() && isUse()) {
301        if (NeedComma) OS << ',';
302        OS << "undef";
303        NeedComma = true;
304      }
305      if (isInternalRead()) {
306        if (NeedComma) OS << ',';
307        OS << "internal";
308        NeedComma = true;
309      }
310      if (isTied()) {
311        if (NeedComma) OS << ',';
312        OS << "tied";
313        NeedComma = true;
314      }
315      OS << '>';
316    }
317    break;
318  case MachineOperand::MO_Immediate:
319    OS << getImm();
320    break;
321  case MachineOperand::MO_CImmediate:
322    getCImm()->getValue().print(OS, false);
323    break;
324  case MachineOperand::MO_FPImmediate:
325    if (getFPImm()->getType()->isFloatTy())
326      OS << getFPImm()->getValueAPF().convertToFloat();
327    else
328      OS << getFPImm()->getValueAPF().convertToDouble();
329    break;
330  case MachineOperand::MO_MachineBasicBlock:
331    OS << "<BB#" << getMBB()->getNumber() << ">";
332    break;
333  case MachineOperand::MO_FrameIndex:
334    OS << "<fi#" << getIndex() << '>';
335    break;
336  case MachineOperand::MO_ConstantPoolIndex:
337    OS << "<cp#" << getIndex();
338    if (getOffset()) OS << "+" << getOffset();
339    OS << '>';
340    break;
341  case MachineOperand::MO_TargetIndex:
342    OS << "<ti#" << getIndex();
343    if (getOffset()) OS << "+" << getOffset();
344    OS << '>';
345    break;
346  case MachineOperand::MO_JumpTableIndex:
347    OS << "<jt#" << getIndex() << '>';
348    break;
349  case MachineOperand::MO_GlobalAddress:
350    OS << "<ga:";
351    WriteAsOperand(OS, getGlobal(), /*PrintType=*/false);
352    if (getOffset()) OS << "+" << getOffset();
353    OS << '>';
354    break;
355  case MachineOperand::MO_ExternalSymbol:
356    OS << "<es:" << getSymbolName();
357    if (getOffset()) OS << "+" << getOffset();
358    OS << '>';
359    break;
360  case MachineOperand::MO_BlockAddress:
361    OS << '<';
362    WriteAsOperand(OS, getBlockAddress(), /*PrintType=*/false);
363    OS << '>';
364    break;
365  case MachineOperand::MO_RegisterMask:
366    OS << "<regmask>";
367    break;
368  case MachineOperand::MO_Metadata:
369    OS << '<';
370    WriteAsOperand(OS, getMetadata(), /*PrintType=*/false);
371    OS << '>';
372    break;
373  case MachineOperand::MO_MCSymbol:
374    OS << "<MCSym=" << *getMCSymbol() << '>';
375    break;
376  }
377
378  if (unsigned TF = getTargetFlags())
379    OS << "[TF=" << TF << ']';
380}
381
382//===----------------------------------------------------------------------===//
383// MachineMemOperand Implementation
384//===----------------------------------------------------------------------===//
385
386/// getAddrSpace - Return the LLVM IR address space number that this pointer
387/// points into.
388unsigned MachinePointerInfo::getAddrSpace() const {
389  if (V == 0) return 0;
390  return cast<PointerType>(V->getType())->getAddressSpace();
391}
392
393/// getConstantPool - Return a MachinePointerInfo record that refers to the
394/// constant pool.
395MachinePointerInfo MachinePointerInfo::getConstantPool() {
396  return MachinePointerInfo(PseudoSourceValue::getConstantPool());
397}
398
399/// getFixedStack - Return a MachinePointerInfo record that refers to the
400/// the specified FrameIndex.
401MachinePointerInfo MachinePointerInfo::getFixedStack(int FI, int64_t offset) {
402  return MachinePointerInfo(PseudoSourceValue::getFixedStack(FI), offset);
403}
404
405MachinePointerInfo MachinePointerInfo::getJumpTable() {
406  return MachinePointerInfo(PseudoSourceValue::getJumpTable());
407}
408
409MachinePointerInfo MachinePointerInfo::getGOT() {
410  return MachinePointerInfo(PseudoSourceValue::getGOT());
411}
412
413MachinePointerInfo MachinePointerInfo::getStack(int64_t Offset) {
414  return MachinePointerInfo(PseudoSourceValue::getStack(), Offset);
415}
416
417MachineMemOperand::MachineMemOperand(MachinePointerInfo ptrinfo, unsigned f,
418                                     uint64_t s, unsigned int a,
419                                     const MDNode *TBAAInfo,
420                                     const MDNode *Ranges)
421  : PtrInfo(ptrinfo), Size(s),
422    Flags((f & ((1 << MOMaxBits) - 1)) | ((Log2_32(a) + 1) << MOMaxBits)),
423    TBAAInfo(TBAAInfo), Ranges(Ranges) {
424  assert((PtrInfo.V == 0 || isa<PointerType>(PtrInfo.V->getType())) &&
425         "invalid pointer value");
426  assert(getBaseAlignment() == a && "Alignment is not a power of 2!");
427  assert((isLoad() || isStore()) && "Not a load/store!");
428}
429
430/// Profile - Gather unique data for the object.
431///
432void MachineMemOperand::Profile(FoldingSetNodeID &ID) const {
433  ID.AddInteger(getOffset());
434  ID.AddInteger(Size);
435  ID.AddPointer(getValue());
436  ID.AddInteger(Flags);
437}
438
439void MachineMemOperand::refineAlignment(const MachineMemOperand *MMO) {
440  // The Value and Offset may differ due to CSE. But the flags and size
441  // should be the same.
442  assert(MMO->getFlags() == getFlags() && "Flags mismatch!");
443  assert(MMO->getSize() == getSize() && "Size mismatch!");
444
445  if (MMO->getBaseAlignment() >= getBaseAlignment()) {
446    // Update the alignment value.
447    Flags = (Flags & ((1 << MOMaxBits) - 1)) |
448      ((Log2_32(MMO->getBaseAlignment()) + 1) << MOMaxBits);
449    // Also update the base and offset, because the new alignment may
450    // not be applicable with the old ones.
451    PtrInfo = MMO->PtrInfo;
452  }
453}
454
455/// getAlignment - Return the minimum known alignment in bytes of the
456/// actual memory reference.
457uint64_t MachineMemOperand::getAlignment() const {
458  return MinAlign(getBaseAlignment(), getOffset());
459}
460
461raw_ostream &llvm::operator<<(raw_ostream &OS, const MachineMemOperand &MMO) {
462  assert((MMO.isLoad() || MMO.isStore()) &&
463         "SV has to be a load, store or both.");
464
465  if (MMO.isVolatile())
466    OS << "Volatile ";
467
468  if (MMO.isLoad())
469    OS << "LD";
470  if (MMO.isStore())
471    OS << "ST";
472  OS << MMO.getSize();
473
474  // Print the address information.
475  OS << "[";
476  if (!MMO.getValue())
477    OS << "<unknown>";
478  else
479    WriteAsOperand(OS, MMO.getValue(), /*PrintType=*/false);
480
481  // If the alignment of the memory reference itself differs from the alignment
482  // of the base pointer, print the base alignment explicitly, next to the base
483  // pointer.
484  if (MMO.getBaseAlignment() != MMO.getAlignment())
485    OS << "(align=" << MMO.getBaseAlignment() << ")";
486
487  if (MMO.getOffset() != 0)
488    OS << "+" << MMO.getOffset();
489  OS << "]";
490
491  // Print the alignment of the reference.
492  if (MMO.getBaseAlignment() != MMO.getAlignment() ||
493      MMO.getBaseAlignment() != MMO.getSize())
494    OS << "(align=" << MMO.getAlignment() << ")";
495
496  // Print TBAA info.
497  if (const MDNode *TBAAInfo = MMO.getTBAAInfo()) {
498    OS << "(tbaa=";
499    if (TBAAInfo->getNumOperands() > 0)
500      WriteAsOperand(OS, TBAAInfo->getOperand(0), /*PrintType=*/false);
501    else
502      OS << "<unknown>";
503    OS << ")";
504  }
505
506  // Print nontemporal info.
507  if (MMO.isNonTemporal())
508    OS << "(nontemporal)";
509
510  return OS;
511}
512
513//===----------------------------------------------------------------------===//
514// MachineInstr Implementation
515//===----------------------------------------------------------------------===//
516
517/// MachineInstr ctor - This constructor creates a dummy MachineInstr with
518/// MCID NULL and no operands.
519MachineInstr::MachineInstr()
520  : MCID(0), Flags(0), AsmPrinterFlags(0),
521    NumMemRefs(0), MemRefs(0),
522    Parent(0) {
523  // Make sure that we get added to a machine basicblock
524  LeakDetector::addGarbageObject(this);
525}
526
527void MachineInstr::addImplicitDefUseOperands() {
528  if (MCID->ImplicitDefs)
529    for (const uint16_t *ImpDefs = MCID->getImplicitDefs(); *ImpDefs; ++ImpDefs)
530      addOperand(MachineOperand::CreateReg(*ImpDefs, true, true));
531  if (MCID->ImplicitUses)
532    for (const uint16_t *ImpUses = MCID->getImplicitUses(); *ImpUses; ++ImpUses)
533      addOperand(MachineOperand::CreateReg(*ImpUses, false, true));
534}
535
536/// MachineInstr ctor - This constructor creates a MachineInstr and adds the
537/// implicit operands. It reserves space for the number of operands specified by
538/// the MCInstrDesc.
539MachineInstr::MachineInstr(const MCInstrDesc &tid, bool NoImp)
540  : MCID(&tid), Flags(0), AsmPrinterFlags(0),
541    NumMemRefs(0), MemRefs(0), Parent(0) {
542  unsigned NumImplicitOps = 0;
543  if (!NoImp)
544    NumImplicitOps = MCID->getNumImplicitDefs() + MCID->getNumImplicitUses();
545  Operands.reserve(NumImplicitOps + MCID->getNumOperands());
546  if (!NoImp)
547    addImplicitDefUseOperands();
548  // Make sure that we get added to a machine basicblock
549  LeakDetector::addGarbageObject(this);
550}
551
552/// MachineInstr ctor - As above, but with a DebugLoc.
553MachineInstr::MachineInstr(const MCInstrDesc &tid, const DebugLoc dl,
554                           bool NoImp)
555  : MCID(&tid), Flags(0), AsmPrinterFlags(0),
556    NumMemRefs(0), MemRefs(0), Parent(0), debugLoc(dl) {
557  unsigned NumImplicitOps = 0;
558  if (!NoImp)
559    NumImplicitOps = MCID->getNumImplicitDefs() + MCID->getNumImplicitUses();
560  Operands.reserve(NumImplicitOps + MCID->getNumOperands());
561  if (!NoImp)
562    addImplicitDefUseOperands();
563  // Make sure that we get added to a machine basicblock
564  LeakDetector::addGarbageObject(this);
565}
566
567/// MachineInstr ctor - Work exactly the same as the ctor two above, except
568/// that the MachineInstr is created and added to the end of the specified
569/// basic block.
570MachineInstr::MachineInstr(MachineBasicBlock *MBB, const MCInstrDesc &tid)
571  : MCID(&tid), Flags(0), AsmPrinterFlags(0),
572    NumMemRefs(0), MemRefs(0), Parent(0) {
573  assert(MBB && "Cannot use inserting ctor with null basic block!");
574  unsigned NumImplicitOps =
575    MCID->getNumImplicitDefs() + MCID->getNumImplicitUses();
576  Operands.reserve(NumImplicitOps + MCID->getNumOperands());
577  addImplicitDefUseOperands();
578  // Make sure that we get added to a machine basicblock
579  LeakDetector::addGarbageObject(this);
580  MBB->push_back(this);  // Add instruction to end of basic block!
581}
582
583/// MachineInstr ctor - As above, but with a DebugLoc.
584///
585MachineInstr::MachineInstr(MachineBasicBlock *MBB, const DebugLoc dl,
586                           const MCInstrDesc &tid)
587  : MCID(&tid), Flags(0), AsmPrinterFlags(0),
588    NumMemRefs(0), MemRefs(0), Parent(0), debugLoc(dl) {
589  assert(MBB && "Cannot use inserting ctor with null basic block!");
590  unsigned NumImplicitOps =
591    MCID->getNumImplicitDefs() + MCID->getNumImplicitUses();
592  Operands.reserve(NumImplicitOps + MCID->getNumOperands());
593  addImplicitDefUseOperands();
594  // Make sure that we get added to a machine basicblock
595  LeakDetector::addGarbageObject(this);
596  MBB->push_back(this);  // Add instruction to end of basic block!
597}
598
599/// MachineInstr ctor - Copies MachineInstr arg exactly
600///
601MachineInstr::MachineInstr(MachineFunction &MF, const MachineInstr &MI)
602  : MCID(&MI.getDesc()), Flags(0), AsmPrinterFlags(0),
603    NumMemRefs(MI.NumMemRefs), MemRefs(MI.MemRefs),
604    Parent(0), debugLoc(MI.getDebugLoc()) {
605  Operands.reserve(MI.getNumOperands());
606
607  // Add operands
608  for (unsigned i = 0; i != MI.getNumOperands(); ++i)
609    addOperand(MI.getOperand(i));
610
611  // Copy all the flags.
612  Flags = MI.Flags;
613
614  // Set parent to null.
615  Parent = 0;
616
617  LeakDetector::addGarbageObject(this);
618}
619
620MachineInstr::~MachineInstr() {
621  LeakDetector::removeGarbageObject(this);
622#ifndef NDEBUG
623  for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
624    assert(Operands[i].ParentMI == this && "ParentMI mismatch!");
625    assert((!Operands[i].isReg() || !Operands[i].isOnRegUseList()) &&
626           "Reg operand def/use list corrupted");
627  }
628#endif
629}
630
631/// getRegInfo - If this instruction is embedded into a MachineFunction,
632/// return the MachineRegisterInfo object for the current function, otherwise
633/// return null.
634MachineRegisterInfo *MachineInstr::getRegInfo() {
635  if (MachineBasicBlock *MBB = getParent())
636    return &MBB->getParent()->getRegInfo();
637  return 0;
638}
639
640/// RemoveRegOperandsFromUseLists - Unlink all of the register operands in
641/// this instruction from their respective use lists.  This requires that the
642/// operands already be on their use lists.
643void MachineInstr::RemoveRegOperandsFromUseLists(MachineRegisterInfo &MRI) {
644  for (unsigned i = 0, e = Operands.size(); i != e; ++i)
645    if (Operands[i].isReg())
646      MRI.removeRegOperandFromUseList(&Operands[i]);
647}
648
649/// AddRegOperandsToUseLists - Add all of the register operands in
650/// this instruction from their respective use lists.  This requires that the
651/// operands not be on their use lists yet.
652void MachineInstr::AddRegOperandsToUseLists(MachineRegisterInfo &MRI) {
653  for (unsigned i = 0, e = Operands.size(); i != e; ++i)
654    if (Operands[i].isReg())
655      MRI.addRegOperandToUseList(&Operands[i]);
656}
657
658/// addOperand - Add the specified operand to the instruction.  If it is an
659/// implicit operand, it is added to the end of the operand list.  If it is
660/// an explicit operand it is added at the end of the explicit operand list
661/// (before the first implicit operand).
662void MachineInstr::addOperand(const MachineOperand &Op) {
663  assert(MCID && "Cannot add operands before providing an instr descriptor");
664  bool isImpReg = Op.isReg() && Op.isImplicit();
665  MachineRegisterInfo *RegInfo = getRegInfo();
666
667  // If the Operands backing store is reallocated, all register operands must
668  // be removed and re-added to RegInfo.  It is storing pointers to operands.
669  bool Reallocate = RegInfo &&
670    !Operands.empty() && Operands.size() == Operands.capacity();
671
672  // Find the insert location for the new operand.  Implicit registers go at
673  // the end, everything goes before the implicit regs.
674  unsigned OpNo = Operands.size();
675
676  // Remove all the implicit operands from RegInfo if they need to be shifted.
677  // FIXME: Allow mixed explicit and implicit operands on inline asm.
678  // InstrEmitter::EmitSpecialNode() is marking inline asm clobbers as
679  // implicit-defs, but they must not be moved around.  See the FIXME in
680  // InstrEmitter.cpp.
681  if (!isImpReg && !isInlineAsm()) {
682    while (OpNo && Operands[OpNo-1].isReg() && Operands[OpNo-1].isImplicit()) {
683      --OpNo;
684      if (RegInfo)
685        RegInfo->removeRegOperandFromUseList(&Operands[OpNo]);
686    }
687  }
688
689  // OpNo now points as the desired insertion point.  Unless this is a variadic
690  // instruction, only implicit regs are allowed beyond MCID->getNumOperands().
691  // RegMask operands go between the explicit and implicit operands.
692  assert((isImpReg || Op.isRegMask() || MCID->isVariadic() ||
693          OpNo < MCID->getNumOperands()) &&
694         "Trying to add an operand to a machine instr that is already done!");
695
696  // All operands from OpNo have been removed from RegInfo.  If the Operands
697  // backing store needs to be reallocated, we also need to remove any other
698  // register operands.
699  if (Reallocate)
700    for (unsigned i = 0; i != OpNo; ++i)
701      if (Operands[i].isReg())
702        RegInfo->removeRegOperandFromUseList(&Operands[i]);
703
704  // Insert the new operand at OpNo.
705  Operands.insert(Operands.begin() + OpNo, Op);
706  Operands[OpNo].ParentMI = this;
707
708  // The Operands backing store has now been reallocated, so we can re-add the
709  // operands before OpNo.
710  if (Reallocate)
711    for (unsigned i = 0; i != OpNo; ++i)
712      if (Operands[i].isReg())
713        RegInfo->addRegOperandToUseList(&Operands[i]);
714
715  // When adding a register operand, tell RegInfo about it.
716  if (Operands[OpNo].isReg()) {
717    // Ensure isOnRegUseList() returns false, regardless of Op's status.
718    Operands[OpNo].Contents.Reg.Prev = 0;
719    // Ignore existing IsTied bit. This is not a property that can be copied.
720    Operands[OpNo].IsTied = false;
721    // Add the new operand to RegInfo.
722    if (RegInfo)
723      RegInfo->addRegOperandToUseList(&Operands[OpNo]);
724    // Set the IsTied bit if MC indicates this use is tied to a def.
725    if (Operands[OpNo].isUse()) {
726      int DefIdx = MCID->getOperandConstraint(OpNo, MCOI::TIED_TO);
727      if (DefIdx != -1) {
728        MachineOperand &DefMO = getOperand(DefIdx);
729        assert(DefMO.isDef() && "Use tied to operand that isn't a def");
730        DefMO.IsTied = true;
731        Operands[OpNo].IsTied = true;
732      }
733    }
734    // If the register operand is flagged as early, mark the operand as such.
735    if (MCID->getOperandConstraint(OpNo, MCOI::EARLY_CLOBBER) != -1)
736      Operands[OpNo].setIsEarlyClobber(true);
737  }
738
739  // Re-add all the implicit ops.
740  if (RegInfo) {
741    for (unsigned i = OpNo + 1, e = Operands.size(); i != e; ++i) {
742      assert(Operands[i].isReg() && "Should only be an implicit reg!");
743      RegInfo->addRegOperandToUseList(&Operands[i]);
744    }
745  }
746}
747
748/// RemoveOperand - Erase an operand  from an instruction, leaving it with one
749/// fewer operand than it started with.
750///
751void MachineInstr::RemoveOperand(unsigned OpNo) {
752  assert(OpNo < Operands.size() && "Invalid operand number");
753  untieRegOperand(OpNo);
754  MachineRegisterInfo *RegInfo = getRegInfo();
755
756  // Special case removing the last one.
757  if (OpNo == Operands.size()-1) {
758    // If needed, remove from the reg def/use list.
759    if (RegInfo && Operands.back().isReg() && Operands.back().isOnRegUseList())
760      RegInfo->removeRegOperandFromUseList(&Operands.back());
761
762    Operands.pop_back();
763    return;
764  }
765
766  // Otherwise, we are removing an interior operand.  If we have reginfo to
767  // update, remove all operands that will be shifted down from their reg lists,
768  // move everything down, then re-add them.
769  if (RegInfo) {
770    for (unsigned i = OpNo, e = Operands.size(); i != e; ++i) {
771      if (Operands[i].isReg())
772        RegInfo->removeRegOperandFromUseList(&Operands[i]);
773    }
774  }
775
776  Operands.erase(Operands.begin()+OpNo);
777
778  if (RegInfo) {
779    for (unsigned i = OpNo, e = Operands.size(); i != e; ++i) {
780      if (Operands[i].isReg())
781        RegInfo->addRegOperandToUseList(&Operands[i]);
782    }
783  }
784}
785
786/// addMemOperand - Add a MachineMemOperand to the machine instruction.
787/// This function should be used only occasionally. The setMemRefs function
788/// is the primary method for setting up a MachineInstr's MemRefs list.
789void MachineInstr::addMemOperand(MachineFunction &MF,
790                                 MachineMemOperand *MO) {
791  mmo_iterator OldMemRefs = MemRefs;
792  uint16_t OldNumMemRefs = NumMemRefs;
793
794  uint16_t NewNum = NumMemRefs + 1;
795  mmo_iterator NewMemRefs = MF.allocateMemRefsArray(NewNum);
796
797  std::copy(OldMemRefs, OldMemRefs + OldNumMemRefs, NewMemRefs);
798  NewMemRefs[NewNum - 1] = MO;
799
800  MemRefs = NewMemRefs;
801  NumMemRefs = NewNum;
802}
803
804bool MachineInstr::hasPropertyInBundle(unsigned Mask, QueryType Type) const {
805  const MachineBasicBlock *MBB = getParent();
806  MachineBasicBlock::const_instr_iterator MII = *this; ++MII;
807  while (MII != MBB->end() && MII->isInsideBundle()) {
808    if (MII->getDesc().getFlags() & Mask) {
809      if (Type == AnyInBundle)
810        return true;
811    } else {
812      if (Type == AllInBundle)
813        return false;
814    }
815    ++MII;
816  }
817
818  return Type == AllInBundle;
819}
820
821bool MachineInstr::isIdenticalTo(const MachineInstr *Other,
822                                 MICheckType Check) const {
823  // If opcodes or number of operands are not the same then the two
824  // instructions are obviously not identical.
825  if (Other->getOpcode() != getOpcode() ||
826      Other->getNumOperands() != getNumOperands())
827    return false;
828
829  if (isBundle()) {
830    // Both instructions are bundles, compare MIs inside the bundle.
831    MachineBasicBlock::const_instr_iterator I1 = *this;
832    MachineBasicBlock::const_instr_iterator E1 = getParent()->instr_end();
833    MachineBasicBlock::const_instr_iterator I2 = *Other;
834    MachineBasicBlock::const_instr_iterator E2= Other->getParent()->instr_end();
835    while (++I1 != E1 && I1->isInsideBundle()) {
836      ++I2;
837      if (I2 == E2 || !I2->isInsideBundle() || !I1->isIdenticalTo(I2, Check))
838        return false;
839    }
840  }
841
842  // Check operands to make sure they match.
843  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
844    const MachineOperand &MO = getOperand(i);
845    const MachineOperand &OMO = Other->getOperand(i);
846    if (!MO.isReg()) {
847      if (!MO.isIdenticalTo(OMO))
848        return false;
849      continue;
850    }
851
852    // Clients may or may not want to ignore defs when testing for equality.
853    // For example, machine CSE pass only cares about finding common
854    // subexpressions, so it's safe to ignore virtual register defs.
855    if (MO.isDef()) {
856      if (Check == IgnoreDefs)
857        continue;
858      else if (Check == IgnoreVRegDefs) {
859        if (TargetRegisterInfo::isPhysicalRegister(MO.getReg()) ||
860            TargetRegisterInfo::isPhysicalRegister(OMO.getReg()))
861          if (MO.getReg() != OMO.getReg())
862            return false;
863      } else {
864        if (!MO.isIdenticalTo(OMO))
865          return false;
866        if (Check == CheckKillDead && MO.isDead() != OMO.isDead())
867          return false;
868      }
869    } else {
870      if (!MO.isIdenticalTo(OMO))
871        return false;
872      if (Check == CheckKillDead && MO.isKill() != OMO.isKill())
873        return false;
874    }
875  }
876  // If DebugLoc does not match then two dbg.values are not identical.
877  if (isDebugValue())
878    if (!getDebugLoc().isUnknown() && !Other->getDebugLoc().isUnknown()
879        && getDebugLoc() != Other->getDebugLoc())
880      return false;
881  return true;
882}
883
884/// removeFromParent - This method unlinks 'this' from the containing basic
885/// block, and returns it, but does not delete it.
886MachineInstr *MachineInstr::removeFromParent() {
887  assert(getParent() && "Not embedded in a basic block!");
888
889  // If it's a bundle then remove the MIs inside the bundle as well.
890  if (isBundle()) {
891    MachineBasicBlock *MBB = getParent();
892    MachineBasicBlock::instr_iterator MII = *this; ++MII;
893    MachineBasicBlock::instr_iterator E = MBB->instr_end();
894    while (MII != E && MII->isInsideBundle()) {
895      MachineInstr *MI = &*MII;
896      ++MII;
897      MBB->remove(MI);
898    }
899  }
900  getParent()->remove(this);
901  return this;
902}
903
904
905/// eraseFromParent - This method unlinks 'this' from the containing basic
906/// block, and deletes it.
907void MachineInstr::eraseFromParent() {
908  assert(getParent() && "Not embedded in a basic block!");
909  // If it's a bundle then remove the MIs inside the bundle as well.
910  if (isBundle()) {
911    MachineBasicBlock *MBB = getParent();
912    MachineBasicBlock::instr_iterator MII = *this; ++MII;
913    MachineBasicBlock::instr_iterator E = MBB->instr_end();
914    while (MII != E && MII->isInsideBundle()) {
915      MachineInstr *MI = &*MII;
916      ++MII;
917      MBB->erase(MI);
918    }
919  }
920  // Erase the individual instruction, which may itself be inside a bundle.
921  getParent()->erase_instr(this);
922}
923
924
925/// getNumExplicitOperands - Returns the number of non-implicit operands.
926///
927unsigned MachineInstr::getNumExplicitOperands() const {
928  unsigned NumOperands = MCID->getNumOperands();
929  if (!MCID->isVariadic())
930    return NumOperands;
931
932  for (unsigned i = NumOperands, e = getNumOperands(); i != e; ++i) {
933    const MachineOperand &MO = getOperand(i);
934    if (!MO.isReg() || !MO.isImplicit())
935      NumOperands++;
936  }
937  return NumOperands;
938}
939
940/// isBundled - Return true if this instruction part of a bundle. This is true
941/// if either itself or its following instruction is marked "InsideBundle".
942bool MachineInstr::isBundled() const {
943  if (isInsideBundle())
944    return true;
945  MachineBasicBlock::const_instr_iterator nextMI = this;
946  ++nextMI;
947  return nextMI != Parent->instr_end() && nextMI->isInsideBundle();
948}
949
950bool MachineInstr::isStackAligningInlineAsm() const {
951  if (isInlineAsm()) {
952    unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
953    if (ExtraInfo & InlineAsm::Extra_IsAlignStack)
954      return true;
955  }
956  return false;
957}
958
959int MachineInstr::findInlineAsmFlagIdx(unsigned OpIdx,
960                                       unsigned *GroupNo) const {
961  assert(isInlineAsm() && "Expected an inline asm instruction");
962  assert(OpIdx < getNumOperands() && "OpIdx out of range");
963
964  // Ignore queries about the initial operands.
965  if (OpIdx < InlineAsm::MIOp_FirstOperand)
966    return -1;
967
968  unsigned Group = 0;
969  unsigned NumOps;
970  for (unsigned i = InlineAsm::MIOp_FirstOperand, e = getNumOperands(); i < e;
971       i += NumOps) {
972    const MachineOperand &FlagMO = getOperand(i);
973    // If we reach the implicit register operands, stop looking.
974    if (!FlagMO.isImm())
975      return -1;
976    NumOps = 1 + InlineAsm::getNumOperandRegisters(FlagMO.getImm());
977    if (i + NumOps > OpIdx) {
978      if (GroupNo)
979        *GroupNo = Group;
980      return i;
981    }
982    ++Group;
983  }
984  return -1;
985}
986
987const TargetRegisterClass*
988MachineInstr::getRegClassConstraint(unsigned OpIdx,
989                                    const TargetInstrInfo *TII,
990                                    const TargetRegisterInfo *TRI) const {
991  assert(getParent() && "Can't have an MBB reference here!");
992  assert(getParent()->getParent() && "Can't have an MF reference here!");
993  const MachineFunction &MF = *getParent()->getParent();
994
995  // Most opcodes have fixed constraints in their MCInstrDesc.
996  if (!isInlineAsm())
997    return TII->getRegClass(getDesc(), OpIdx, TRI, MF);
998
999  if (!getOperand(OpIdx).isReg())
1000    return NULL;
1001
1002  // For tied uses on inline asm, get the constraint from the def.
1003  unsigned DefIdx;
1004  if (getOperand(OpIdx).isUse() && isRegTiedToDefOperand(OpIdx, &DefIdx))
1005    OpIdx = DefIdx;
1006
1007  // Inline asm stores register class constraints in the flag word.
1008  int FlagIdx = findInlineAsmFlagIdx(OpIdx);
1009  if (FlagIdx < 0)
1010    return NULL;
1011
1012  unsigned Flag = getOperand(FlagIdx).getImm();
1013  unsigned RCID;
1014  if (InlineAsm::hasRegClassConstraint(Flag, RCID))
1015    return TRI->getRegClass(RCID);
1016
1017  // Assume that all registers in a memory operand are pointers.
1018  if (InlineAsm::getKind(Flag) == InlineAsm::Kind_Mem)
1019    return TRI->getPointerRegClass(MF);
1020
1021  return NULL;
1022}
1023
1024/// getBundleSize - Return the number of instructions inside the MI bundle.
1025unsigned MachineInstr::getBundleSize() const {
1026  assert(isBundle() && "Expecting a bundle");
1027
1028  MachineBasicBlock::const_instr_iterator I = *this;
1029  unsigned Size = 0;
1030  while ((++I)->isInsideBundle()) {
1031    ++Size;
1032  }
1033  assert(Size > 1 && "Malformed bundle");
1034
1035  return Size;
1036}
1037
1038/// findRegisterUseOperandIdx() - Returns the MachineOperand that is a use of
1039/// the specific register or -1 if it is not found. It further tightens
1040/// the search criteria to a use that kills the register if isKill is true.
1041int MachineInstr::findRegisterUseOperandIdx(unsigned Reg, bool isKill,
1042                                          const TargetRegisterInfo *TRI) const {
1043  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1044    const MachineOperand &MO = getOperand(i);
1045    if (!MO.isReg() || !MO.isUse())
1046      continue;
1047    unsigned MOReg = MO.getReg();
1048    if (!MOReg)
1049      continue;
1050    if (MOReg == Reg ||
1051        (TRI &&
1052         TargetRegisterInfo::isPhysicalRegister(MOReg) &&
1053         TargetRegisterInfo::isPhysicalRegister(Reg) &&
1054         TRI->isSubRegister(MOReg, Reg)))
1055      if (!isKill || MO.isKill())
1056        return i;
1057  }
1058  return -1;
1059}
1060
1061/// readsWritesVirtualRegister - Return a pair of bools (reads, writes)
1062/// indicating if this instruction reads or writes Reg. This also considers
1063/// partial defines.
1064std::pair<bool,bool>
1065MachineInstr::readsWritesVirtualRegister(unsigned Reg,
1066                                         SmallVectorImpl<unsigned> *Ops) const {
1067  bool PartDef = false; // Partial redefine.
1068  bool FullDef = false; // Full define.
1069  bool Use = false;
1070
1071  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1072    const MachineOperand &MO = getOperand(i);
1073    if (!MO.isReg() || MO.getReg() != Reg)
1074      continue;
1075    if (Ops)
1076      Ops->push_back(i);
1077    if (MO.isUse())
1078      Use |= !MO.isUndef();
1079    else if (MO.getSubReg() && !MO.isUndef())
1080      // A partial <def,undef> doesn't count as reading the register.
1081      PartDef = true;
1082    else
1083      FullDef = true;
1084  }
1085  // A partial redefine uses Reg unless there is also a full define.
1086  return std::make_pair(Use || (PartDef && !FullDef), PartDef || FullDef);
1087}
1088
1089/// findRegisterDefOperandIdx() - Returns the operand index that is a def of
1090/// the specified register or -1 if it is not found. If isDead is true, defs
1091/// that are not dead are skipped. If TargetRegisterInfo is non-null, then it
1092/// also checks if there is a def of a super-register.
1093int
1094MachineInstr::findRegisterDefOperandIdx(unsigned Reg, bool isDead, bool Overlap,
1095                                        const TargetRegisterInfo *TRI) const {
1096  bool isPhys = TargetRegisterInfo::isPhysicalRegister(Reg);
1097  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1098    const MachineOperand &MO = getOperand(i);
1099    // Accept regmask operands when Overlap is set.
1100    // Ignore them when looking for a specific def operand (Overlap == false).
1101    if (isPhys && Overlap && MO.isRegMask() && MO.clobbersPhysReg(Reg))
1102      return i;
1103    if (!MO.isReg() || !MO.isDef())
1104      continue;
1105    unsigned MOReg = MO.getReg();
1106    bool Found = (MOReg == Reg);
1107    if (!Found && TRI && isPhys &&
1108        TargetRegisterInfo::isPhysicalRegister(MOReg)) {
1109      if (Overlap)
1110        Found = TRI->regsOverlap(MOReg, Reg);
1111      else
1112        Found = TRI->isSubRegister(MOReg, Reg);
1113    }
1114    if (Found && (!isDead || MO.isDead()))
1115      return i;
1116  }
1117  return -1;
1118}
1119
1120/// findFirstPredOperandIdx() - Find the index of the first operand in the
1121/// operand list that is used to represent the predicate. It returns -1 if
1122/// none is found.
1123int MachineInstr::findFirstPredOperandIdx() const {
1124  // Don't call MCID.findFirstPredOperandIdx() because this variant
1125  // is sometimes called on an instruction that's not yet complete, and
1126  // so the number of operands is less than the MCID indicates. In
1127  // particular, the PTX target does this.
1128  const MCInstrDesc &MCID = getDesc();
1129  if (MCID.isPredicable()) {
1130    for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
1131      if (MCID.OpInfo[i].isPredicate())
1132        return i;
1133  }
1134
1135  return -1;
1136}
1137
1138/// Given the index of a tied register operand, find the operand it is tied to.
1139/// Defs are tied to uses and vice versa. Returns the index of the tied operand
1140/// which must exist.
1141unsigned MachineInstr::findTiedOperandIdx(unsigned OpIdx) const {
1142  // It doesn't usually happen, but an instruction can have multiple pairs of
1143  // tied operands.
1144  SmallVector<unsigned, 4> Uses, Defs;
1145  unsigned PairNo = ~0u;
1146  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1147    const MachineOperand &MO = getOperand(i);
1148    if (!MO.isReg() || !MO.isTied())
1149      continue;
1150    if (MO.isUse()) {
1151      if (i == OpIdx)
1152        PairNo = Uses.size();
1153      Uses.push_back(i);
1154    } else {
1155      if (i == OpIdx)
1156        PairNo = Defs.size();
1157      Defs.push_back(i);
1158    }
1159  }
1160  // For each tied use there must be a tied def and vice versa.
1161  assert(Uses.size() == Defs.size() && "Tied uses and defs don't match");
1162  assert(PairNo < Uses.size() && "OpIdx must be a tied register operand");
1163
1164  // Find the matching operand.
1165  return (getOperand(OpIdx).isDef() ? Uses : Defs)[PairNo];
1166}
1167
1168/// isRegTiedToUseOperand - Given the index of a register def operand,
1169/// check if the register def is tied to a source operand, due to either
1170/// two-address elimination or inline assembly constraints. Returns the
1171/// first tied use operand index by reference is UseOpIdx is not null.
1172bool MachineInstr::
1173isRegTiedToUseOperand(unsigned DefOpIdx, unsigned *UseOpIdx) const {
1174  if (isInlineAsm()) {
1175    assert(DefOpIdx > InlineAsm::MIOp_FirstOperand);
1176    const MachineOperand &MO = getOperand(DefOpIdx);
1177    if (!MO.isReg() || !MO.isDef() || MO.getReg() == 0)
1178      return false;
1179    // Determine the actual operand index that corresponds to this index.
1180    unsigned DefNo = 0;
1181    int FlagIdx = findInlineAsmFlagIdx(DefOpIdx, &DefNo);
1182    if (FlagIdx < 0)
1183      return false;
1184
1185    // Which part of the group is DefOpIdx?
1186    unsigned DefPart = DefOpIdx - (FlagIdx + 1);
1187
1188    for (unsigned i = InlineAsm::MIOp_FirstOperand, e = getNumOperands();
1189         i != e; ++i) {
1190      const MachineOperand &FMO = getOperand(i);
1191      if (!FMO.isImm())
1192        continue;
1193      if (i+1 >= e || !getOperand(i+1).isReg() || !getOperand(i+1).isUse())
1194        continue;
1195      unsigned Idx;
1196      if (InlineAsm::isUseOperandTiedToDef(FMO.getImm(), Idx) &&
1197          Idx == DefNo) {
1198        if (UseOpIdx)
1199          *UseOpIdx = (unsigned)i + 1 + DefPart;
1200        return true;
1201      }
1202    }
1203    return false;
1204  }
1205
1206  assert(getOperand(DefOpIdx).isDef() && "DefOpIdx is not a def!");
1207  const MCInstrDesc &MCID = getDesc();
1208  for (unsigned i = 0, e = MCID.getNumOperands(); i != e; ++i) {
1209    const MachineOperand &MO = getOperand(i);
1210    if (MO.isReg() && MO.isUse() &&
1211        MCID.getOperandConstraint(i, MCOI::TIED_TO) == (int)DefOpIdx) {
1212      if (UseOpIdx)
1213        *UseOpIdx = (unsigned)i;
1214      return true;
1215    }
1216  }
1217  return false;
1218}
1219
1220/// isRegTiedToDefOperand - Return true if the operand of the specified index
1221/// is a register use and it is tied to an def operand. It also returns the def
1222/// operand index by reference.
1223bool MachineInstr::
1224isRegTiedToDefOperand(unsigned UseOpIdx, unsigned *DefOpIdx) const {
1225  if (isInlineAsm()) {
1226    const MachineOperand &MO = getOperand(UseOpIdx);
1227    if (!MO.isReg() || !MO.isUse() || MO.getReg() == 0)
1228      return false;
1229
1230    // Find the flag operand corresponding to UseOpIdx
1231    int FlagIdx = findInlineAsmFlagIdx(UseOpIdx);
1232    if (FlagIdx < 0)
1233      return false;
1234
1235    const MachineOperand &UFMO = getOperand(FlagIdx);
1236    unsigned DefNo;
1237    if (InlineAsm::isUseOperandTiedToDef(UFMO.getImm(), DefNo)) {
1238      if (!DefOpIdx)
1239        return true;
1240
1241      unsigned DefIdx = InlineAsm::MIOp_FirstOperand;
1242      // Remember to adjust the index. First operand is asm string, second is
1243      // the HasSideEffects and AlignStack bits, then there is a flag for each.
1244      while (DefNo) {
1245        const MachineOperand &FMO = getOperand(DefIdx);
1246        assert(FMO.isImm());
1247        // Skip over this def.
1248        DefIdx += InlineAsm::getNumOperandRegisters(FMO.getImm()) + 1;
1249        --DefNo;
1250      }
1251      *DefOpIdx = DefIdx + UseOpIdx - FlagIdx;
1252      return true;
1253    }
1254    return false;
1255  }
1256
1257  const MCInstrDesc &MCID = getDesc();
1258  if (UseOpIdx >= MCID.getNumOperands())
1259    return false;
1260  const MachineOperand &MO = getOperand(UseOpIdx);
1261  if (!MO.isReg() || !MO.isUse())
1262    return false;
1263  int DefIdx = MCID.getOperandConstraint(UseOpIdx, MCOI::TIED_TO);
1264  if (DefIdx == -1)
1265    return false;
1266  if (DefOpIdx)
1267    *DefOpIdx = (unsigned)DefIdx;
1268  return true;
1269}
1270
1271/// clearKillInfo - Clears kill flags on all operands.
1272///
1273void MachineInstr::clearKillInfo() {
1274  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1275    MachineOperand &MO = getOperand(i);
1276    if (MO.isReg() && MO.isUse())
1277      MO.setIsKill(false);
1278  }
1279}
1280
1281/// copyKillDeadInfo - Copies kill / dead operand properties from MI.
1282///
1283void MachineInstr::copyKillDeadInfo(const MachineInstr *MI) {
1284  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
1285    const MachineOperand &MO = MI->getOperand(i);
1286    if (!MO.isReg() || (!MO.isKill() && !MO.isDead()))
1287      continue;
1288    for (unsigned j = 0, ee = getNumOperands(); j != ee; ++j) {
1289      MachineOperand &MOp = getOperand(j);
1290      if (!MOp.isIdenticalTo(MO))
1291        continue;
1292      if (MO.isKill())
1293        MOp.setIsKill();
1294      else
1295        MOp.setIsDead();
1296      break;
1297    }
1298  }
1299}
1300
1301/// copyPredicates - Copies predicate operand(s) from MI.
1302void MachineInstr::copyPredicates(const MachineInstr *MI) {
1303  assert(!isBundle() && "MachineInstr::copyPredicates() can't handle bundles");
1304
1305  const MCInstrDesc &MCID = MI->getDesc();
1306  if (!MCID.isPredicable())
1307    return;
1308  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
1309    if (MCID.OpInfo[i].isPredicate()) {
1310      // Predicated operands must be last operands.
1311      addOperand(MI->getOperand(i));
1312    }
1313  }
1314}
1315
1316void MachineInstr::substituteRegister(unsigned FromReg,
1317                                      unsigned ToReg,
1318                                      unsigned SubIdx,
1319                                      const TargetRegisterInfo &RegInfo) {
1320  if (TargetRegisterInfo::isPhysicalRegister(ToReg)) {
1321    if (SubIdx)
1322      ToReg = RegInfo.getSubReg(ToReg, SubIdx);
1323    for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1324      MachineOperand &MO = getOperand(i);
1325      if (!MO.isReg() || MO.getReg() != FromReg)
1326        continue;
1327      MO.substPhysReg(ToReg, RegInfo);
1328    }
1329  } else {
1330    for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1331      MachineOperand &MO = getOperand(i);
1332      if (!MO.isReg() || MO.getReg() != FromReg)
1333        continue;
1334      MO.substVirtReg(ToReg, SubIdx, RegInfo);
1335    }
1336  }
1337}
1338
1339/// isSafeToMove - Return true if it is safe to move this instruction. If
1340/// SawStore is set to true, it means that there is a store (or call) between
1341/// the instruction's location and its intended destination.
1342bool MachineInstr::isSafeToMove(const TargetInstrInfo *TII,
1343                                AliasAnalysis *AA,
1344                                bool &SawStore) const {
1345  // Ignore stuff that we obviously can't move.
1346  //
1347  // Treat volatile loads as stores. This is not strictly necessary for
1348  // volatiles, but it is required for atomic loads. It is now allowed to move
1349  // a load across an atomic load with Ordering > Monotonic.
1350  if (mayStore() || isCall() ||
1351      (mayLoad() && hasVolatileMemoryRef())) {
1352    SawStore = true;
1353    return false;
1354  }
1355
1356  if (isLabel() || isDebugValue() ||
1357      isTerminator() || hasUnmodeledSideEffects())
1358    return false;
1359
1360  // See if this instruction does a load.  If so, we have to guarantee that the
1361  // loaded value doesn't change between the load and the its intended
1362  // destination. The check for isInvariantLoad gives the targe the chance to
1363  // classify the load as always returning a constant, e.g. a constant pool
1364  // load.
1365  if (mayLoad() && !isInvariantLoad(AA))
1366    // Otherwise, this is a real load.  If there is a store between the load and
1367    // end of block, we can't move it.
1368    return !SawStore;
1369
1370  return true;
1371}
1372
1373/// isSafeToReMat - Return true if it's safe to rematerialize the specified
1374/// instruction which defined the specified register instead of copying it.
1375bool MachineInstr::isSafeToReMat(const TargetInstrInfo *TII,
1376                                 AliasAnalysis *AA,
1377                                 unsigned DstReg) const {
1378  bool SawStore = false;
1379  if (!TII->isTriviallyReMaterializable(this, AA) ||
1380      !isSafeToMove(TII, AA, SawStore))
1381    return false;
1382  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1383    const MachineOperand &MO = getOperand(i);
1384    if (!MO.isReg())
1385      continue;
1386    // FIXME: For now, do not remat any instruction with register operands.
1387    // Later on, we can loosen the restriction is the register operands have
1388    // not been modified between the def and use. Note, this is different from
1389    // MachineSink because the code is no longer in two-address form (at least
1390    // partially).
1391    if (MO.isUse())
1392      return false;
1393    else if (!MO.isDead() && MO.getReg() != DstReg)
1394      return false;
1395  }
1396  return true;
1397}
1398
1399/// hasVolatileMemoryRef - Return true if this instruction may have a
1400/// volatile memory reference, or if the information describing the
1401/// memory reference is not available. Return false if it is known to
1402/// have no volatile memory references.
1403bool MachineInstr::hasVolatileMemoryRef() const {
1404  // An instruction known never to access memory won't have a volatile access.
1405  if (!mayStore() &&
1406      !mayLoad() &&
1407      !isCall() &&
1408      !hasUnmodeledSideEffects())
1409    return false;
1410
1411  // Otherwise, if the instruction has no memory reference information,
1412  // conservatively assume it wasn't preserved.
1413  if (memoperands_empty())
1414    return true;
1415
1416  // Check the memory reference information for volatile references.
1417  for (mmo_iterator I = memoperands_begin(), E = memoperands_end(); I != E; ++I)
1418    if ((*I)->isVolatile())
1419      return true;
1420
1421  return false;
1422}
1423
1424/// isInvariantLoad - Return true if this instruction is loading from a
1425/// location whose value is invariant across the function.  For example,
1426/// loading a value from the constant pool or from the argument area
1427/// of a function if it does not change.  This should only return true of
1428/// *all* loads the instruction does are invariant (if it does multiple loads).
1429bool MachineInstr::isInvariantLoad(AliasAnalysis *AA) const {
1430  // If the instruction doesn't load at all, it isn't an invariant load.
1431  if (!mayLoad())
1432    return false;
1433
1434  // If the instruction has lost its memoperands, conservatively assume that
1435  // it may not be an invariant load.
1436  if (memoperands_empty())
1437    return false;
1438
1439  const MachineFrameInfo *MFI = getParent()->getParent()->getFrameInfo();
1440
1441  for (mmo_iterator I = memoperands_begin(),
1442       E = memoperands_end(); I != E; ++I) {
1443    if ((*I)->isVolatile()) return false;
1444    if ((*I)->isStore()) return false;
1445    if ((*I)->isInvariant()) return true;
1446
1447    if (const Value *V = (*I)->getValue()) {
1448      // A load from a constant PseudoSourceValue is invariant.
1449      if (const PseudoSourceValue *PSV = dyn_cast<PseudoSourceValue>(V))
1450        if (PSV->isConstant(MFI))
1451          continue;
1452      // If we have an AliasAnalysis, ask it whether the memory is constant.
1453      if (AA && AA->pointsToConstantMemory(
1454                      AliasAnalysis::Location(V, (*I)->getSize(),
1455                                              (*I)->getTBAAInfo())))
1456        continue;
1457    }
1458
1459    // Otherwise assume conservatively.
1460    return false;
1461  }
1462
1463  // Everything checks out.
1464  return true;
1465}
1466
1467/// isConstantValuePHI - If the specified instruction is a PHI that always
1468/// merges together the same virtual register, return the register, otherwise
1469/// return 0.
1470unsigned MachineInstr::isConstantValuePHI() const {
1471  if (!isPHI())
1472    return 0;
1473  assert(getNumOperands() >= 3 &&
1474         "It's illegal to have a PHI without source operands");
1475
1476  unsigned Reg = getOperand(1).getReg();
1477  for (unsigned i = 3, e = getNumOperands(); i < e; i += 2)
1478    if (getOperand(i).getReg() != Reg)
1479      return 0;
1480  return Reg;
1481}
1482
1483bool MachineInstr::hasUnmodeledSideEffects() const {
1484  if (hasProperty(MCID::UnmodeledSideEffects))
1485    return true;
1486  if (isInlineAsm()) {
1487    unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1488    if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
1489      return true;
1490  }
1491
1492  return false;
1493}
1494
1495/// allDefsAreDead - Return true if all the defs of this instruction are dead.
1496///
1497bool MachineInstr::allDefsAreDead() const {
1498  for (unsigned i = 0, e = getNumOperands(); i < e; ++i) {
1499    const MachineOperand &MO = getOperand(i);
1500    if (!MO.isReg() || MO.isUse())
1501      continue;
1502    if (!MO.isDead())
1503      return false;
1504  }
1505  return true;
1506}
1507
1508/// copyImplicitOps - Copy implicit register operands from specified
1509/// instruction to this instruction.
1510void MachineInstr::copyImplicitOps(const MachineInstr *MI) {
1511  for (unsigned i = MI->getDesc().getNumOperands(), e = MI->getNumOperands();
1512       i != e; ++i) {
1513    const MachineOperand &MO = MI->getOperand(i);
1514    if (MO.isReg() && MO.isImplicit())
1515      addOperand(MO);
1516  }
1517}
1518
1519void MachineInstr::dump() const {
1520  dbgs() << "  " << *this;
1521}
1522
1523static void printDebugLoc(DebugLoc DL, const MachineFunction *MF,
1524                         raw_ostream &CommentOS) {
1525  const LLVMContext &Ctx = MF->getFunction()->getContext();
1526  if (!DL.isUnknown()) {          // Print source line info.
1527    DIScope Scope(DL.getScope(Ctx));
1528    // Omit the directory, because it's likely to be long and uninteresting.
1529    if (Scope.Verify())
1530      CommentOS << Scope.getFilename();
1531    else
1532      CommentOS << "<unknown>";
1533    CommentOS << ':' << DL.getLine();
1534    if (DL.getCol() != 0)
1535      CommentOS << ':' << DL.getCol();
1536    DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(DL.getInlinedAt(Ctx));
1537    if (!InlinedAtDL.isUnknown()) {
1538      CommentOS << " @[ ";
1539      printDebugLoc(InlinedAtDL, MF, CommentOS);
1540      CommentOS << " ]";
1541    }
1542  }
1543}
1544
1545void MachineInstr::print(raw_ostream &OS, const TargetMachine *TM) const {
1546  // We can be a bit tidier if we know the TargetMachine and/or MachineFunction.
1547  const MachineFunction *MF = 0;
1548  const MachineRegisterInfo *MRI = 0;
1549  if (const MachineBasicBlock *MBB = getParent()) {
1550    MF = MBB->getParent();
1551    if (!TM && MF)
1552      TM = &MF->getTarget();
1553    if (MF)
1554      MRI = &MF->getRegInfo();
1555  }
1556
1557  // Save a list of virtual registers.
1558  SmallVector<unsigned, 8> VirtRegs;
1559
1560  // Print explicitly defined operands on the left of an assignment syntax.
1561  unsigned StartOp = 0, e = getNumOperands();
1562  for (; StartOp < e && getOperand(StartOp).isReg() &&
1563         getOperand(StartOp).isDef() &&
1564         !getOperand(StartOp).isImplicit();
1565       ++StartOp) {
1566    if (StartOp != 0) OS << ", ";
1567    getOperand(StartOp).print(OS, TM);
1568    unsigned Reg = getOperand(StartOp).getReg();
1569    if (TargetRegisterInfo::isVirtualRegister(Reg))
1570      VirtRegs.push_back(Reg);
1571  }
1572
1573  if (StartOp != 0)
1574    OS << " = ";
1575
1576  // Print the opcode name.
1577  if (TM && TM->getInstrInfo())
1578    OS << TM->getInstrInfo()->getName(getOpcode());
1579  else
1580    OS << "UNKNOWN";
1581
1582  // Print the rest of the operands.
1583  bool OmittedAnyCallClobbers = false;
1584  bool FirstOp = true;
1585  unsigned AsmDescOp = ~0u;
1586  unsigned AsmOpCount = 0;
1587
1588  if (isInlineAsm() && e >= InlineAsm::MIOp_FirstOperand) {
1589    // Print asm string.
1590    OS << " ";
1591    getOperand(InlineAsm::MIOp_AsmString).print(OS, TM);
1592
1593    // Print HasSideEffects, IsAlignStack
1594    unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1595    if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
1596      OS << " [sideeffect]";
1597    if (ExtraInfo & InlineAsm::Extra_IsAlignStack)
1598      OS << " [alignstack]";
1599
1600    StartOp = AsmDescOp = InlineAsm::MIOp_FirstOperand;
1601    FirstOp = false;
1602  }
1603
1604
1605  for (unsigned i = StartOp, e = getNumOperands(); i != e; ++i) {
1606    const MachineOperand &MO = getOperand(i);
1607
1608    if (MO.isReg() && TargetRegisterInfo::isVirtualRegister(MO.getReg()))
1609      VirtRegs.push_back(MO.getReg());
1610
1611    // Omit call-clobbered registers which aren't used anywhere. This makes
1612    // call instructions much less noisy on targets where calls clobber lots
1613    // of registers. Don't rely on MO.isDead() because we may be called before
1614    // LiveVariables is run, or we may be looking at a non-allocatable reg.
1615    if (MF && isCall() &&
1616        MO.isReg() && MO.isImplicit() && MO.isDef()) {
1617      unsigned Reg = MO.getReg();
1618      if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
1619        const MachineRegisterInfo &MRI = MF->getRegInfo();
1620        if (MRI.use_empty(Reg) && !MRI.isLiveOut(Reg)) {
1621          bool HasAliasLive = false;
1622          for (MCRegAliasIterator AI(Reg, TM->getRegisterInfo(), true);
1623               AI.isValid(); ++AI) {
1624            unsigned AliasReg = *AI;
1625            if (!MRI.use_empty(AliasReg) || MRI.isLiveOut(AliasReg)) {
1626              HasAliasLive = true;
1627              break;
1628            }
1629          }
1630          if (!HasAliasLive) {
1631            OmittedAnyCallClobbers = true;
1632            continue;
1633          }
1634        }
1635      }
1636    }
1637
1638    if (FirstOp) FirstOp = false; else OS << ",";
1639    OS << " ";
1640    if (i < getDesc().NumOperands) {
1641      const MCOperandInfo &MCOI = getDesc().OpInfo[i];
1642      if (MCOI.isPredicate())
1643        OS << "pred:";
1644      if (MCOI.isOptionalDef())
1645        OS << "opt:";
1646    }
1647    if (isDebugValue() && MO.isMetadata()) {
1648      // Pretty print DBG_VALUE instructions.
1649      const MDNode *MD = MO.getMetadata();
1650      if (const MDString *MDS = dyn_cast<MDString>(MD->getOperand(2)))
1651        OS << "!\"" << MDS->getString() << '\"';
1652      else
1653        MO.print(OS, TM);
1654    } else if (TM && (isInsertSubreg() || isRegSequence()) && MO.isImm()) {
1655      OS << TM->getRegisterInfo()->getSubRegIndexName(MO.getImm());
1656    } else if (i == AsmDescOp && MO.isImm()) {
1657      // Pretty print the inline asm operand descriptor.
1658      OS << '$' << AsmOpCount++;
1659      unsigned Flag = MO.getImm();
1660      switch (InlineAsm::getKind(Flag)) {
1661      case InlineAsm::Kind_RegUse:             OS << ":[reguse"; break;
1662      case InlineAsm::Kind_RegDef:             OS << ":[regdef"; break;
1663      case InlineAsm::Kind_RegDefEarlyClobber: OS << ":[regdef-ec"; break;
1664      case InlineAsm::Kind_Clobber:            OS << ":[clobber"; break;
1665      case InlineAsm::Kind_Imm:                OS << ":[imm"; break;
1666      case InlineAsm::Kind_Mem:                OS << ":[mem"; break;
1667      default: OS << ":[??" << InlineAsm::getKind(Flag); break;
1668      }
1669
1670      unsigned RCID = 0;
1671      if (InlineAsm::hasRegClassConstraint(Flag, RCID)) {
1672        if (TM)
1673          OS << ':' << TM->getRegisterInfo()->getRegClass(RCID)->getName();
1674        else
1675          OS << ":RC" << RCID;
1676      }
1677
1678      unsigned TiedTo = 0;
1679      if (InlineAsm::isUseOperandTiedToDef(Flag, TiedTo))
1680        OS << " tiedto:$" << TiedTo;
1681
1682      OS << ']';
1683
1684      // Compute the index of the next operand descriptor.
1685      AsmDescOp += 1 + InlineAsm::getNumOperandRegisters(Flag);
1686    } else
1687      MO.print(OS, TM);
1688  }
1689
1690  // Briefly indicate whether any call clobbers were omitted.
1691  if (OmittedAnyCallClobbers) {
1692    if (!FirstOp) OS << ",";
1693    OS << " ...";
1694  }
1695
1696  bool HaveSemi = false;
1697  if (Flags) {
1698    if (!HaveSemi) OS << ";"; HaveSemi = true;
1699    OS << " flags: ";
1700
1701    if (Flags & FrameSetup)
1702      OS << "FrameSetup";
1703  }
1704
1705  if (!memoperands_empty()) {
1706    if (!HaveSemi) OS << ";"; HaveSemi = true;
1707
1708    OS << " mem:";
1709    for (mmo_iterator i = memoperands_begin(), e = memoperands_end();
1710         i != e; ++i) {
1711      OS << **i;
1712      if (llvm::next(i) != e)
1713        OS << " ";
1714    }
1715  }
1716
1717  // Print the regclass of any virtual registers encountered.
1718  if (MRI && !VirtRegs.empty()) {
1719    if (!HaveSemi) OS << ";"; HaveSemi = true;
1720    for (unsigned i = 0; i != VirtRegs.size(); ++i) {
1721      const TargetRegisterClass *RC = MRI->getRegClass(VirtRegs[i]);
1722      OS << " " << RC->getName() << ':' << PrintReg(VirtRegs[i]);
1723      for (unsigned j = i+1; j != VirtRegs.size();) {
1724        if (MRI->getRegClass(VirtRegs[j]) != RC) {
1725          ++j;
1726          continue;
1727        }
1728        if (VirtRegs[i] != VirtRegs[j])
1729          OS << "," << PrintReg(VirtRegs[j]);
1730        VirtRegs.erase(VirtRegs.begin()+j);
1731      }
1732    }
1733  }
1734
1735  // Print debug location information.
1736  if (isDebugValue() && getOperand(e - 1).isMetadata()) {
1737    if (!HaveSemi) OS << ";"; HaveSemi = true;
1738    DIVariable DV(getOperand(e - 1).getMetadata());
1739    OS << " line no:" <<  DV.getLineNumber();
1740    if (MDNode *InlinedAt = DV.getInlinedAt()) {
1741      DebugLoc InlinedAtDL = DebugLoc::getFromDILocation(InlinedAt);
1742      if (!InlinedAtDL.isUnknown()) {
1743        OS << " inlined @[ ";
1744        printDebugLoc(InlinedAtDL, MF, OS);
1745        OS << " ]";
1746      }
1747    }
1748  } else if (!debugLoc.isUnknown() && MF) {
1749    if (!HaveSemi) OS << ";"; HaveSemi = true;
1750    OS << " dbg:";
1751    printDebugLoc(debugLoc, MF, OS);
1752  }
1753
1754  OS << '\n';
1755}
1756
1757bool MachineInstr::addRegisterKilled(unsigned IncomingReg,
1758                                     const TargetRegisterInfo *RegInfo,
1759                                     bool AddIfNotFound) {
1760  bool isPhysReg = TargetRegisterInfo::isPhysicalRegister(IncomingReg);
1761  bool hasAliases = isPhysReg &&
1762    MCRegAliasIterator(IncomingReg, RegInfo, false).isValid();
1763  bool Found = false;
1764  SmallVector<unsigned,4> DeadOps;
1765  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1766    MachineOperand &MO = getOperand(i);
1767    if (!MO.isReg() || !MO.isUse() || MO.isUndef())
1768      continue;
1769    unsigned Reg = MO.getReg();
1770    if (!Reg)
1771      continue;
1772
1773    if (Reg == IncomingReg) {
1774      if (!Found) {
1775        if (MO.isKill())
1776          // The register is already marked kill.
1777          return true;
1778        if (isPhysReg && isRegTiedToDefOperand(i))
1779          // Two-address uses of physregs must not be marked kill.
1780          return true;
1781        MO.setIsKill();
1782        Found = true;
1783      }
1784    } else if (hasAliases && MO.isKill() &&
1785               TargetRegisterInfo::isPhysicalRegister(Reg)) {
1786      // A super-register kill already exists.
1787      if (RegInfo->isSuperRegister(IncomingReg, Reg))
1788        return true;
1789      if (RegInfo->isSubRegister(IncomingReg, Reg))
1790        DeadOps.push_back(i);
1791    }
1792  }
1793
1794  // Trim unneeded kill operands.
1795  while (!DeadOps.empty()) {
1796    unsigned OpIdx = DeadOps.back();
1797    if (getOperand(OpIdx).isImplicit())
1798      RemoveOperand(OpIdx);
1799    else
1800      getOperand(OpIdx).setIsKill(false);
1801    DeadOps.pop_back();
1802  }
1803
1804  // If not found, this means an alias of one of the operands is killed. Add a
1805  // new implicit operand if required.
1806  if (!Found && AddIfNotFound) {
1807    addOperand(MachineOperand::CreateReg(IncomingReg,
1808                                         false /*IsDef*/,
1809                                         true  /*IsImp*/,
1810                                         true  /*IsKill*/));
1811    return true;
1812  }
1813  return Found;
1814}
1815
1816void MachineInstr::clearRegisterKills(unsigned Reg,
1817                                      const TargetRegisterInfo *RegInfo) {
1818  if (!TargetRegisterInfo::isPhysicalRegister(Reg))
1819    RegInfo = 0;
1820  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1821    MachineOperand &MO = getOperand(i);
1822    if (!MO.isReg() || !MO.isUse() || !MO.isKill())
1823      continue;
1824    unsigned OpReg = MO.getReg();
1825    if (OpReg == Reg || (RegInfo && RegInfo->isSuperRegister(Reg, OpReg)))
1826      MO.setIsKill(false);
1827  }
1828}
1829
1830bool MachineInstr::addRegisterDead(unsigned IncomingReg,
1831                                   const TargetRegisterInfo *RegInfo,
1832                                   bool AddIfNotFound) {
1833  bool isPhysReg = TargetRegisterInfo::isPhysicalRegister(IncomingReg);
1834  bool hasAliases = isPhysReg &&
1835    MCRegAliasIterator(IncomingReg, RegInfo, false).isValid();
1836  bool Found = false;
1837  SmallVector<unsigned,4> DeadOps;
1838  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1839    MachineOperand &MO = getOperand(i);
1840    if (!MO.isReg() || !MO.isDef())
1841      continue;
1842    unsigned Reg = MO.getReg();
1843    if (!Reg)
1844      continue;
1845
1846    if (Reg == IncomingReg) {
1847      MO.setIsDead();
1848      Found = true;
1849    } else if (hasAliases && MO.isDead() &&
1850               TargetRegisterInfo::isPhysicalRegister(Reg)) {
1851      // There exists a super-register that's marked dead.
1852      if (RegInfo->isSuperRegister(IncomingReg, Reg))
1853        return true;
1854      if (RegInfo->isSubRegister(IncomingReg, Reg))
1855        DeadOps.push_back(i);
1856    }
1857  }
1858
1859  // Trim unneeded dead operands.
1860  while (!DeadOps.empty()) {
1861    unsigned OpIdx = DeadOps.back();
1862    if (getOperand(OpIdx).isImplicit())
1863      RemoveOperand(OpIdx);
1864    else
1865      getOperand(OpIdx).setIsDead(false);
1866    DeadOps.pop_back();
1867  }
1868
1869  // If not found, this means an alias of one of the operands is dead. Add a
1870  // new implicit operand if required.
1871  if (Found || !AddIfNotFound)
1872    return Found;
1873
1874  addOperand(MachineOperand::CreateReg(IncomingReg,
1875                                       true  /*IsDef*/,
1876                                       true  /*IsImp*/,
1877                                       false /*IsKill*/,
1878                                       true  /*IsDead*/));
1879  return true;
1880}
1881
1882void MachineInstr::addRegisterDefined(unsigned IncomingReg,
1883                                      const TargetRegisterInfo *RegInfo) {
1884  if (TargetRegisterInfo::isPhysicalRegister(IncomingReg)) {
1885    MachineOperand *MO = findRegisterDefOperand(IncomingReg, false, RegInfo);
1886    if (MO)
1887      return;
1888  } else {
1889    for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1890      const MachineOperand &MO = getOperand(i);
1891      if (MO.isReg() && MO.getReg() == IncomingReg && MO.isDef() &&
1892          MO.getSubReg() == 0)
1893        return;
1894    }
1895  }
1896  addOperand(MachineOperand::CreateReg(IncomingReg,
1897                                       true  /*IsDef*/,
1898                                       true  /*IsImp*/));
1899}
1900
1901void MachineInstr::setPhysRegsDeadExcept(ArrayRef<unsigned> UsedRegs,
1902                                         const TargetRegisterInfo &TRI) {
1903  bool HasRegMask = false;
1904  for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1905    MachineOperand &MO = getOperand(i);
1906    if (MO.isRegMask()) {
1907      HasRegMask = true;
1908      continue;
1909    }
1910    if (!MO.isReg() || !MO.isDef()) continue;
1911    unsigned Reg = MO.getReg();
1912    if (!TargetRegisterInfo::isPhysicalRegister(Reg)) continue;
1913    bool Dead = true;
1914    for (ArrayRef<unsigned>::iterator I = UsedRegs.begin(), E = UsedRegs.end();
1915         I != E; ++I)
1916      if (TRI.regsOverlap(*I, Reg)) {
1917        Dead = false;
1918        break;
1919      }
1920    // If there are no uses, including partial uses, the def is dead.
1921    if (Dead) MO.setIsDead();
1922  }
1923
1924  // This is a call with a register mask operand.
1925  // Mask clobbers are always dead, so add defs for the non-dead defines.
1926  if (HasRegMask)
1927    for (ArrayRef<unsigned>::iterator I = UsedRegs.begin(), E = UsedRegs.end();
1928         I != E; ++I)
1929      addRegisterDefined(*I, &TRI);
1930}
1931
1932unsigned
1933MachineInstrExpressionTrait::getHashValue(const MachineInstr* const &MI) {
1934  // Build up a buffer of hash code components.
1935  SmallVector<size_t, 8> HashComponents;
1936  HashComponents.reserve(MI->getNumOperands() + 1);
1937  HashComponents.push_back(MI->getOpcode());
1938  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
1939    const MachineOperand &MO = MI->getOperand(i);
1940    if (MO.isReg() && MO.isDef() &&
1941        TargetRegisterInfo::isVirtualRegister(MO.getReg()))
1942      continue;  // Skip virtual register defs.
1943
1944    HashComponents.push_back(hash_value(MO));
1945  }
1946  return hash_combine_range(HashComponents.begin(), HashComponents.end());
1947}
1948
1949void MachineInstr::emitError(StringRef Msg) const {
1950  // Find the source location cookie.
1951  unsigned LocCookie = 0;
1952  const MDNode *LocMD = 0;
1953  for (unsigned i = getNumOperands(); i != 0; --i) {
1954    if (getOperand(i-1).isMetadata() &&
1955        (LocMD = getOperand(i-1).getMetadata()) &&
1956        LocMD->getNumOperands() != 0) {
1957      if (const ConstantInt *CI = dyn_cast<ConstantInt>(LocMD->getOperand(0))) {
1958        LocCookie = CI->getZExtValue();
1959        break;
1960      }
1961    }
1962  }
1963
1964  if (const MachineBasicBlock *MBB = getParent())
1965    if (const MachineFunction *MF = MBB->getParent())
1966      return MF->getMMI().getModule()->getContext().emitError(LocCookie, Msg);
1967  report_fatal_error(Msg);
1968}
1969