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/ADT/APFloat.h"
16 #include "llvm/ADT/ArrayRef.h"
17 #include "llvm/ADT/FoldingSet.h"
18 #include "llvm/ADT/Hashing.h"
19 #include "llvm/ADT/None.h"
20 #include "llvm/ADT/STLExtras.h"
21 #include "llvm/ADT/SmallString.h"
22 #include "llvm/ADT/SmallVector.h"
23 #include "llvm/Analysis/AliasAnalysis.h"
24 #include "llvm/Analysis/Loads.h"
25 #include "llvm/Analysis/MemoryLocation.h"
26 #include "llvm/CodeGen/GlobalISel/RegisterBank.h"
27 #include "llvm/CodeGen/MachineBasicBlock.h"
28 #include "llvm/CodeGen/MachineFunction.h"
29 #include "llvm/CodeGen/MachineInstrBuilder.h"
30 #include "llvm/CodeGen/MachineInstrBundle.h"
31 #include "llvm/CodeGen/MachineMemOperand.h"
32 #include "llvm/CodeGen/MachineModuleInfo.h"
33 #include "llvm/CodeGen/MachineOperand.h"
34 #include "llvm/CodeGen/MachineRegisterInfo.h"
35 #include "llvm/CodeGen/PseudoSourceValue.h"
36 #include "llvm/IR/Constants.h"
37 #include "llvm/IR/DebugInfoMetadata.h"
38 #include "llvm/IR/DebugLoc.h"
39 #include "llvm/IR/DerivedTypes.h"
40 #include "llvm/IR/Function.h"
41 #include "llvm/IR/InlineAsm.h"
42 #include "llvm/IR/InstrTypes.h"
43 #include "llvm/IR/Intrinsics.h"
44 #include "llvm/IR/LLVMContext.h"
45 #include "llvm/IR/Metadata.h"
46 #include "llvm/IR/Module.h"
47 #include "llvm/IR/ModuleSlotTracker.h"
48 #include "llvm/IR/Type.h"
49 #include "llvm/IR/Value.h"
50 #include "llvm/MC/MCInstrDesc.h"
51 #include "llvm/MC/MCRegisterInfo.h"
52 #include "llvm/MC/MCSymbol.h"
53 #include "llvm/Support/Casting.h"
54 #include "llvm/Support/CommandLine.h"
55 #include "llvm/Support/Compiler.h"
56 #include "llvm/Support/Debug.h"
57 #include "llvm/Support/ErrorHandling.h"
58 #include "llvm/Support/LowLevelTypeImpl.h"
59 #include "llvm/Support/MathExtras.h"
60 #include "llvm/Support/raw_ostream.h"
61 #include "llvm/Target/TargetInstrInfo.h"
62 #include "llvm/Target/TargetIntrinsicInfo.h"
63 #include "llvm/Target/TargetMachine.h"
64 #include "llvm/Target/TargetRegisterInfo.h"
65 #include "llvm/Target/TargetSubtargetInfo.h"
66 #include <algorithm>
67 #include <cassert>
68 #include <cstddef>
69 #include <cstdint>
70 #include <cstring>
71 #include <iterator>
72 #include <utility>
73 
74 using namespace llvm;
75 
76 static cl::opt<bool> PrintWholeRegMask(
77     "print-whole-regmask",
78     cl::desc("Print the full contents of regmask operands in IR dumps"),
79     cl::init(true), cl::Hidden);
80 
81 //===----------------------------------------------------------------------===//
82 // MachineOperand Implementation
83 //===----------------------------------------------------------------------===//
84 
85 void MachineOperand::setReg(unsigned Reg) {
86   if (getReg() == Reg) return; // No change.
87 
88   // Otherwise, we have to change the register.  If this operand is embedded
89   // into a machine function, we need to update the old and new register's
90   // use/def lists.
91   if (MachineInstr *MI = getParent())
92     if (MachineBasicBlock *MBB = MI->getParent())
93       if (MachineFunction *MF = MBB->getParent()) {
94         MachineRegisterInfo &MRI = MF->getRegInfo();
95         MRI.removeRegOperandFromUseList(this);
96         SmallContents.RegNo = Reg;
97         MRI.addRegOperandToUseList(this);
98         return;
99       }
100 
101   // Otherwise, just change the register, no problem.  :)
102   SmallContents.RegNo = Reg;
103 }
104 
105 void MachineOperand::substVirtReg(unsigned Reg, unsigned SubIdx,
106                                   const TargetRegisterInfo &TRI) {
107   assert(TargetRegisterInfo::isVirtualRegister(Reg));
108   if (SubIdx && getSubReg())
109     SubIdx = TRI.composeSubRegIndices(SubIdx, getSubReg());
110   setReg(Reg);
111   if (SubIdx)
112     setSubReg(SubIdx);
113 }
114 
115 void MachineOperand::substPhysReg(unsigned Reg, const TargetRegisterInfo &TRI) {
116   assert(TargetRegisterInfo::isPhysicalRegister(Reg));
117   if (getSubReg()) {
118     Reg = TRI.getSubReg(Reg, getSubReg());
119     // Note that getSubReg() may return 0 if the sub-register doesn't exist.
120     // That won't happen in legal code.
121     setSubReg(0);
122     if (isDef())
123       setIsUndef(false);
124   }
125   setReg(Reg);
126 }
127 
128 /// Change a def to a use, or a use to a def.
129 void MachineOperand::setIsDef(bool Val) {
130   assert(isReg() && "Wrong MachineOperand accessor");
131   assert((!Val || !isDebug()) && "Marking a debug operation as def");
132   if (IsDef == Val)
133     return;
134   // MRI may keep uses and defs in different list positions.
135   if (MachineInstr *MI = getParent())
136     if (MachineBasicBlock *MBB = MI->getParent())
137       if (MachineFunction *MF = MBB->getParent()) {
138         MachineRegisterInfo &MRI = MF->getRegInfo();
139         MRI.removeRegOperandFromUseList(this);
140         IsDef = Val;
141         MRI.addRegOperandToUseList(this);
142         return;
143       }
144   IsDef = Val;
145 }
146 
147 // If this operand is currently a register operand, and if this is in a
148 // function, deregister the operand from the register's use/def list.
149 void MachineOperand::removeRegFromUses() {
150   if (!isReg() || !isOnRegUseList())
151     return;
152 
153   if (MachineInstr *MI = getParent()) {
154     if (MachineBasicBlock *MBB = MI->getParent()) {
155       if (MachineFunction *MF = MBB->getParent())
156         MF->getRegInfo().removeRegOperandFromUseList(this);
157     }
158   }
159 }
160 
161 /// ChangeToImmediate - Replace this operand with a new immediate operand of
162 /// the specified value.  If an operand is known to be an immediate already,
163 /// the setImm method should be used.
164 void MachineOperand::ChangeToImmediate(int64_t ImmVal) {
165   assert((!isReg() || !isTied()) && "Cannot change a tied operand into an imm");
166 
167   removeRegFromUses();
168 
169   OpKind = MO_Immediate;
170   Contents.ImmVal = ImmVal;
171 }
172 
173 void MachineOperand::ChangeToFPImmediate(const ConstantFP *FPImm) {
174   assert((!isReg() || !isTied()) && "Cannot change a tied operand into an imm");
175 
176   removeRegFromUses();
177 
178   OpKind = MO_FPImmediate;
179   Contents.CFP = FPImm;
180 }
181 
182 void MachineOperand::ChangeToES(const char *SymName, unsigned char TargetFlags) {
183   assert((!isReg() || !isTied()) &&
184          "Cannot change a tied operand into an external symbol");
185 
186   removeRegFromUses();
187 
188   OpKind = MO_ExternalSymbol;
189   Contents.OffsetedInfo.Val.SymbolName = SymName;
190   setOffset(0); // Offset is always 0.
191   setTargetFlags(TargetFlags);
192 }
193 
194 void MachineOperand::ChangeToMCSymbol(MCSymbol *Sym) {
195   assert((!isReg() || !isTied()) &&
196          "Cannot change a tied operand into an MCSymbol");
197 
198   removeRegFromUses();
199 
200   OpKind = MO_MCSymbol;
201   Contents.Sym = Sym;
202 }
203 
204 void MachineOperand::ChangeToFrameIndex(int Idx) {
205   assert((!isReg() || !isTied()) &&
206          "Cannot change a tied operand into a FrameIndex");
207 
208   removeRegFromUses();
209 
210   OpKind = MO_FrameIndex;
211   setIndex(Idx);
212 }
213 
214 /// ChangeToRegister - Replace this operand with a new register operand of
215 /// the specified value.  If an operand is known to be an register already,
216 /// the setReg method should be used.
217 void MachineOperand::ChangeToRegister(unsigned Reg, bool isDef, bool isImp,
218                                       bool isKill, bool isDead, bool isUndef,
219                                       bool isDebug) {
220   MachineRegisterInfo *RegInfo = nullptr;
221   if (MachineInstr *MI = getParent())
222     if (MachineBasicBlock *MBB = MI->getParent())
223       if (MachineFunction *MF = MBB->getParent())
224         RegInfo = &MF->getRegInfo();
225   // If this operand is already a register operand, remove it from the
226   // register's use/def lists.
227   bool WasReg = isReg();
228   if (RegInfo && WasReg)
229     RegInfo->removeRegOperandFromUseList(this);
230 
231   // Change this to a register and set the reg#.
232   OpKind = MO_Register;
233   SmallContents.RegNo = Reg;
234   SubReg_TargetFlags = 0;
235   IsDef = isDef;
236   IsImp = isImp;
237   IsKill = isKill;
238   IsDead = isDead;
239   IsUndef = isUndef;
240   IsInternalRead = false;
241   IsEarlyClobber = false;
242   IsDebug = isDebug;
243   // Ensure isOnRegUseList() returns false.
244   Contents.Reg.Prev = nullptr;
245   // Preserve the tie when the operand was already a register.
246   if (!WasReg)
247     TiedTo = 0;
248 
249   // If this operand is embedded in a function, add the operand to the
250   // register's use/def list.
251   if (RegInfo)
252     RegInfo->addRegOperandToUseList(this);
253 }
254 
255 /// isIdenticalTo - Return true if this operand is identical to the specified
256 /// operand. Note that this should stay in sync with the hash_value overload
257 /// below.
258 bool MachineOperand::isIdenticalTo(const MachineOperand &Other) const {
259   if (getType() != Other.getType() ||
260       getTargetFlags() != Other.getTargetFlags())
261     return false;
262 
263   switch (getType()) {
264   case MachineOperand::MO_Register:
265     return getReg() == Other.getReg() && isDef() == Other.isDef() &&
266            getSubReg() == Other.getSubReg();
267   case MachineOperand::MO_Immediate:
268     return getImm() == Other.getImm();
269   case MachineOperand::MO_CImmediate:
270     return getCImm() == Other.getCImm();
271   case MachineOperand::MO_FPImmediate:
272     return getFPImm() == Other.getFPImm();
273   case MachineOperand::MO_MachineBasicBlock:
274     return getMBB() == Other.getMBB();
275   case MachineOperand::MO_FrameIndex:
276     return getIndex() == Other.getIndex();
277   case MachineOperand::MO_ConstantPoolIndex:
278   case MachineOperand::MO_TargetIndex:
279     return getIndex() == Other.getIndex() && getOffset() == Other.getOffset();
280   case MachineOperand::MO_JumpTableIndex:
281     return getIndex() == Other.getIndex();
282   case MachineOperand::MO_GlobalAddress:
283     return getGlobal() == Other.getGlobal() && getOffset() == Other.getOffset();
284   case MachineOperand::MO_ExternalSymbol:
285     return strcmp(getSymbolName(), Other.getSymbolName()) == 0 &&
286            getOffset() == Other.getOffset();
287   case MachineOperand::MO_BlockAddress:
288     return getBlockAddress() == Other.getBlockAddress() &&
289            getOffset() == Other.getOffset();
290   case MachineOperand::MO_RegisterMask:
291   case MachineOperand::MO_RegisterLiveOut: {
292     // Shallow compare of the two RegMasks
293     const uint32_t *RegMask = getRegMask();
294     const uint32_t *OtherRegMask = Other.getRegMask();
295     if (RegMask == OtherRegMask)
296       return true;
297 
298     // Calculate the size of the RegMask
299     const MachineFunction *MF = getParent()->getParent()->getParent();
300     const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo();
301     unsigned RegMaskSize = (TRI->getNumRegs() + 31) / 32;
302 
303     // Deep compare of the two RegMasks
304     return std::equal(RegMask, RegMask + RegMaskSize, OtherRegMask);
305   }
306   case MachineOperand::MO_MCSymbol:
307     return getMCSymbol() == Other.getMCSymbol();
308   case MachineOperand::MO_CFIIndex: {
309     const MachineFunction *MF = getParent()->getParent()->getParent();
310     const MachineFunction *OtherMF =
311         Other.getParent()->getParent()->getParent();
312     MCCFIInstruction Inst = MF->getFrameInstructions()[getCFIIndex()];
313     MCCFIInstruction OtherInst =
314         OtherMF->getFrameInstructions()[Other.getCFIIndex()];
315     MCCFIInstruction::OpType op = Inst.getOperation();
316     if (op != OtherInst.getOperation()) return false;
317     if (op == MCCFIInstruction::OpDefCfa || op == MCCFIInstruction::OpOffset ||
318         op == MCCFIInstruction::OpRestore ||
319         op == MCCFIInstruction::OpUndefined ||
320         op == MCCFIInstruction::OpSameValue ||
321         op == MCCFIInstruction::OpDefCfaRegister ||
322         op == MCCFIInstruction::OpRelOffset ||
323         op == MCCFIInstruction::OpRegister)
324       if (Inst.getRegister() != OtherInst.getRegister()) return false;
325     if (op == MCCFIInstruction::OpRegister)
326       if (Inst.getRegister2() != OtherInst.getRegister2()) return false;
327     if (op == MCCFIInstruction::OpDefCfa || op == MCCFIInstruction::OpOffset ||
328         op == MCCFIInstruction::OpRelOffset ||
329         op == MCCFIInstruction::OpDefCfaOffset ||
330         op == MCCFIInstruction::OpAdjustCfaOffset ||
331         op == MCCFIInstruction::OpGnuArgsSize)
332       if (Inst.getOffset() != OtherInst.getOffset()) return false;
333     return true;
334   }
335   case MachineOperand::MO_Metadata:
336     return getMetadata() == Other.getMetadata();
337   case MachineOperand::MO_IntrinsicID:
338     return getIntrinsicID() == Other.getIntrinsicID();
339   case MachineOperand::MO_Predicate:
340     return getPredicate() == Other.getPredicate();
341   }
342   llvm_unreachable("Invalid machine operand type");
343 }
344 
345 // Note: this must stay exactly in sync with isIdenticalTo above.
346 hash_code llvm::hash_value(const MachineOperand &MO) {
347   switch (MO.getType()) {
348   case MachineOperand::MO_Register:
349     // Register operands don't have target flags.
350     return hash_combine(MO.getType(), MO.getReg(), MO.getSubReg(), MO.isDef());
351   case MachineOperand::MO_Immediate:
352     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getImm());
353   case MachineOperand::MO_CImmediate:
354     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getCImm());
355   case MachineOperand::MO_FPImmediate:
356     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getFPImm());
357   case MachineOperand::MO_MachineBasicBlock:
358     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getMBB());
359   case MachineOperand::MO_FrameIndex:
360     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIndex());
361   case MachineOperand::MO_ConstantPoolIndex:
362   case MachineOperand::MO_TargetIndex:
363     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIndex(),
364                         MO.getOffset());
365   case MachineOperand::MO_JumpTableIndex:
366     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIndex());
367   case MachineOperand::MO_ExternalSymbol:
368     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getOffset(),
369                         MO.getSymbolName());
370   case MachineOperand::MO_GlobalAddress:
371     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getGlobal(),
372                         MO.getOffset());
373   case MachineOperand::MO_BlockAddress:
374     return hash_combine(MO.getType(), MO.getTargetFlags(),
375                         MO.getBlockAddress(), MO.getOffset());
376   case MachineOperand::MO_RegisterMask:
377   case MachineOperand::MO_RegisterLiveOut:
378     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getRegMask());
379   case MachineOperand::MO_Metadata:
380     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getMetadata());
381   case MachineOperand::MO_MCSymbol:
382     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getMCSymbol());
383   case MachineOperand::MO_CFIIndex: {
384     const MachineFunction *MF = MO.getParent()->getParent()->getParent();
385     MCCFIInstruction Inst = MF->getFrameInstructions()[MO.getCFIIndex()];
386     return hash_combine(MO.getType(), MO.getTargetFlags(), Inst.getOperation(),
387                         Inst.getRegister(), Inst.getRegister2(),
388                         Inst.getOffset());
389   }
390   case MachineOperand::MO_IntrinsicID:
391     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIntrinsicID());
392   case MachineOperand::MO_Predicate:
393     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getPredicate());
394   }
395   llvm_unreachable("Invalid machine operand type");
396 }
397 
398 void MachineOperand::print(raw_ostream &OS, const TargetRegisterInfo *TRI,
399                            const TargetIntrinsicInfo *IntrinsicInfo) const {
400   ModuleSlotTracker DummyMST(nullptr);
401   print(OS, DummyMST, TRI, IntrinsicInfo);
402 }
403 
404 void MachineOperand::print(raw_ostream &OS, ModuleSlotTracker &MST,
405                            const TargetRegisterInfo *TRI,
406                            const TargetIntrinsicInfo *IntrinsicInfo) const {
407   switch (getType()) {
408   case MachineOperand::MO_Register:
409     OS << PrintReg(getReg(), TRI, getSubReg());
410 
411     if (isDef() || isKill() || isDead() || isImplicit() || isUndef() ||
412         isInternalRead() || isEarlyClobber() || isTied()) {
413       OS << '<';
414       bool NeedComma = false;
415       if (isDef()) {
416         if (NeedComma) OS << ',';
417         if (isEarlyClobber())
418           OS << "earlyclobber,";
419         if (isImplicit())
420           OS << "imp-";
421         OS << "def";
422         NeedComma = true;
423         // <def,read-undef> only makes sense when getSubReg() is set.
424         // Don't clutter the output otherwise.
425         if (isUndef() && getSubReg())
426           OS << ",read-undef";
427       } else if (isImplicit()) {
428         OS << "imp-use";
429         NeedComma = true;
430       }
431 
432       if (isKill()) {
433         if (NeedComma) OS << ',';
434         OS << "kill";
435         NeedComma = true;
436       }
437       if (isDead()) {
438         if (NeedComma) OS << ',';
439         OS << "dead";
440         NeedComma = true;
441       }
442       if (isUndef() && isUse()) {
443         if (NeedComma) OS << ',';
444         OS << "undef";
445         NeedComma = true;
446       }
447       if (isInternalRead()) {
448         if (NeedComma) OS << ',';
449         OS << "internal";
450         NeedComma = true;
451       }
452       if (isTied()) {
453         if (NeedComma) OS << ',';
454         OS << "tied";
455         if (TiedTo != 15)
456           OS << unsigned(TiedTo - 1);
457       }
458       OS << '>';
459     }
460     break;
461   case MachineOperand::MO_Immediate:
462     OS << getImm();
463     break;
464   case MachineOperand::MO_CImmediate:
465     getCImm()->getValue().print(OS, false);
466     break;
467   case MachineOperand::MO_FPImmediate:
468     if (getFPImm()->getType()->isFloatTy()) {
469       OS << getFPImm()->getValueAPF().convertToFloat();
470     } else if (getFPImm()->getType()->isHalfTy()) {
471       APFloat APF = getFPImm()->getValueAPF();
472       bool Unused;
473       APF.convert(APFloat::IEEEsingle(), APFloat::rmNearestTiesToEven, &Unused);
474       OS << "half " << APF.convertToFloat();
475     } else if (getFPImm()->getType()->isFP128Ty()) {
476       APFloat APF = getFPImm()->getValueAPF();
477       SmallString<16> Str;
478       getFPImm()->getValueAPF().toString(Str);
479       OS << "quad " << Str;
480     } else {
481       OS << getFPImm()->getValueAPF().convertToDouble();
482     }
483     break;
484   case MachineOperand::MO_MachineBasicBlock:
485     OS << "<BB#" << getMBB()->getNumber() << ">";
486     break;
487   case MachineOperand::MO_FrameIndex:
488     OS << "<fi#" << getIndex() << '>';
489     break;
490   case MachineOperand::MO_ConstantPoolIndex:
491     OS << "<cp#" << getIndex();
492     if (getOffset()) OS << "+" << getOffset();
493     OS << '>';
494     break;
495   case MachineOperand::MO_TargetIndex:
496     OS << "<ti#" << getIndex();
497     if (getOffset()) OS << "+" << getOffset();
498     OS << '>';
499     break;
500   case MachineOperand::MO_JumpTableIndex:
501     OS << "<jt#" << getIndex() << '>';
502     break;
503   case MachineOperand::MO_GlobalAddress:
504     OS << "<ga:";
505     getGlobal()->printAsOperand(OS, /*PrintType=*/false, MST);
506     if (getOffset()) OS << "+" << getOffset();
507     OS << '>';
508     break;
509   case MachineOperand::MO_ExternalSymbol:
510     OS << "<es:" << getSymbolName();
511     if (getOffset()) OS << "+" << getOffset();
512     OS << '>';
513     break;
514   case MachineOperand::MO_BlockAddress:
515     OS << '<';
516     getBlockAddress()->printAsOperand(OS, /*PrintType=*/false, MST);
517     if (getOffset()) OS << "+" << getOffset();
518     OS << '>';
519     break;
520   case MachineOperand::MO_RegisterMask: {
521     unsigned NumRegsInMask = 0;
522     unsigned NumRegsEmitted = 0;
523     OS << "<regmask";
524     for (unsigned i = 0; i < TRI->getNumRegs(); ++i) {
525       unsigned MaskWord = i / 32;
526       unsigned MaskBit = i % 32;
527       if (getRegMask()[MaskWord] & (1 << MaskBit)) {
528         if (PrintWholeRegMask || NumRegsEmitted <= 10) {
529           OS << " " << PrintReg(i, TRI);
530           NumRegsEmitted++;
531         }
532         NumRegsInMask++;
533       }
534     }
535     if (NumRegsEmitted != NumRegsInMask)
536       OS << " and " << (NumRegsInMask - NumRegsEmitted) << " more...";
537     OS << ">";
538     break;
539   }
540   case MachineOperand::MO_RegisterLiveOut:
541     OS << "<regliveout>";
542     break;
543   case MachineOperand::MO_Metadata:
544     OS << '<';
545     getMetadata()->printAsOperand(OS, MST);
546     OS << '>';
547     break;
548   case MachineOperand::MO_MCSymbol:
549     OS << "<MCSym=" << *getMCSymbol() << '>';
550     break;
551   case MachineOperand::MO_CFIIndex:
552     OS << "<call frame instruction>";
553     break;
554   case MachineOperand::MO_IntrinsicID: {
555     Intrinsic::ID ID = getIntrinsicID();
556     if (ID < Intrinsic::num_intrinsics)
557       OS << "<intrinsic:@" << Intrinsic::getName(ID, None) << '>';
558     else if (IntrinsicInfo)
559       OS << "<intrinsic:@" << IntrinsicInfo->getName(ID) << '>';
560     else
561       OS << "<intrinsic:" << ID << '>';
562     break;
563   }
564   case MachineOperand::MO_Predicate: {
565     auto Pred = static_cast<CmpInst::Predicate>(getPredicate());
566     OS << '<' << (CmpInst::isIntPredicate(Pred) ? "intpred" : "floatpred")
567        << CmpInst::getPredicateName(Pred) << '>';
568     break;
569   }
570   }
571   if (unsigned TF = getTargetFlags())
572     OS << "[TF=" << TF << ']';
573 }
574 
575 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
576 LLVM_DUMP_METHOD void MachineOperand::dump() const {
577   dbgs() << *this << '\n';
578 }
579 #endif
580 
581 //===----------------------------------------------------------------------===//
582 // MachineMemOperand Implementation
583 //===----------------------------------------------------------------------===//
584 
585 /// getAddrSpace - Return the LLVM IR address space number that this pointer
586 /// points into.
587 unsigned MachinePointerInfo::getAddrSpace() const {
588   if (V.isNull() || V.is<const PseudoSourceValue*>()) return 0;
589   return cast<PointerType>(V.get<const Value*>()->getType())->getAddressSpace();
590 }
591 
592 /// isDereferenceable - Return true if V is always dereferenceable for
593 /// Offset + Size byte.
594 bool MachinePointerInfo::isDereferenceable(unsigned Size, LLVMContext &C,
595                                            const DataLayout &DL) const {
596   if (!V.is<const Value*>())
597     return false;
598 
599   const Value *BasePtr = V.get<const Value*>();
600   if (BasePtr == nullptr)
601     return false;
602 
603   return isDereferenceableAndAlignedPointer(BasePtr, 1,
604                                             APInt(DL.getPointerSize(),
605                                                   Offset + Size),
606                                             DL);
607 }
608 
609 /// getConstantPool - Return a MachinePointerInfo record that refers to the
610 /// constant pool.
611 MachinePointerInfo MachinePointerInfo::getConstantPool(MachineFunction &MF) {
612   return MachinePointerInfo(MF.getPSVManager().getConstantPool());
613 }
614 
615 /// getFixedStack - Return a MachinePointerInfo record that refers to the
616 /// the specified FrameIndex.
617 MachinePointerInfo MachinePointerInfo::getFixedStack(MachineFunction &MF,
618                                                      int FI, int64_t Offset) {
619   return MachinePointerInfo(MF.getPSVManager().getFixedStack(FI), Offset);
620 }
621 
622 MachinePointerInfo MachinePointerInfo::getJumpTable(MachineFunction &MF) {
623   return MachinePointerInfo(MF.getPSVManager().getJumpTable());
624 }
625 
626 MachinePointerInfo MachinePointerInfo::getGOT(MachineFunction &MF) {
627   return MachinePointerInfo(MF.getPSVManager().getGOT());
628 }
629 
630 MachinePointerInfo MachinePointerInfo::getStack(MachineFunction &MF,
631                                                 int64_t Offset) {
632   return MachinePointerInfo(MF.getPSVManager().getStack(), Offset);
633 }
634 
635 MachineMemOperand::MachineMemOperand(MachinePointerInfo ptrinfo, Flags f,
636                                      uint64_t s, unsigned int a,
637                                      const AAMDNodes &AAInfo,
638                                      const MDNode *Ranges,
639                                      SynchronizationScope SynchScope,
640                                      AtomicOrdering Ordering,
641                                      AtomicOrdering FailureOrdering)
642     : PtrInfo(ptrinfo), Size(s), FlagVals(f), BaseAlignLog2(Log2_32(a) + 1),
643       AAInfo(AAInfo), Ranges(Ranges) {
644   assert((PtrInfo.V.isNull() || PtrInfo.V.is<const PseudoSourceValue*>() ||
645           isa<PointerType>(PtrInfo.V.get<const Value*>()->getType())) &&
646          "invalid pointer value");
647   assert(getBaseAlignment() == a && "Alignment is not a power of 2!");
648   assert((isLoad() || isStore()) && "Not a load/store!");
649 
650   AtomicInfo.SynchScope = static_cast<unsigned>(SynchScope);
651   assert(getSynchScope() == SynchScope && "Value truncated");
652   AtomicInfo.Ordering = static_cast<unsigned>(Ordering);
653   assert(getOrdering() == Ordering && "Value truncated");
654   AtomicInfo.FailureOrdering = static_cast<unsigned>(FailureOrdering);
655   assert(getFailureOrdering() == FailureOrdering && "Value truncated");
656 }
657 
658 /// Profile - Gather unique data for the object.
659 ///
660 void MachineMemOperand::Profile(FoldingSetNodeID &ID) const {
661   ID.AddInteger(getOffset());
662   ID.AddInteger(Size);
663   ID.AddPointer(getOpaqueValue());
664   ID.AddInteger(getFlags());
665   ID.AddInteger(getBaseAlignment());
666 }
667 
668 void MachineMemOperand::refineAlignment(const MachineMemOperand *MMO) {
669   // The Value and Offset may differ due to CSE. But the flags and size
670   // should be the same.
671   assert(MMO->getFlags() == getFlags() && "Flags mismatch!");
672   assert(MMO->getSize() == getSize() && "Size mismatch!");
673 
674   if (MMO->getBaseAlignment() >= getBaseAlignment()) {
675     // Update the alignment value.
676     BaseAlignLog2 = Log2_32(MMO->getBaseAlignment()) + 1;
677     // Also update the base and offset, because the new alignment may
678     // not be applicable with the old ones.
679     PtrInfo = MMO->PtrInfo;
680   }
681 }
682 
683 /// getAlignment - Return the minimum known alignment in bytes of the
684 /// actual memory reference.
685 uint64_t MachineMemOperand::getAlignment() const {
686   return MinAlign(getBaseAlignment(), getOffset());
687 }
688 
689 void MachineMemOperand::print(raw_ostream &OS) const {
690   ModuleSlotTracker DummyMST(nullptr);
691   print(OS, DummyMST);
692 }
693 void MachineMemOperand::print(raw_ostream &OS, ModuleSlotTracker &MST) const {
694   assert((isLoad() || isStore()) &&
695          "SV has to be a load, store or both.");
696 
697   if (isVolatile())
698     OS << "Volatile ";
699 
700   if (isLoad())
701     OS << "LD";
702   if (isStore())
703     OS << "ST";
704   OS << getSize();
705 
706   // Print the address information.
707   OS << "[";
708   if (const Value *V = getValue())
709     V->printAsOperand(OS, /*PrintType=*/false, MST);
710   else if (const PseudoSourceValue *PSV = getPseudoValue())
711     PSV->printCustom(OS);
712   else
713     OS << "<unknown>";
714 
715   unsigned AS = getAddrSpace();
716   if (AS != 0)
717     OS << "(addrspace=" << AS << ')';
718 
719   // If the alignment of the memory reference itself differs from the alignment
720   // of the base pointer, print the base alignment explicitly, next to the base
721   // pointer.
722   if (getBaseAlignment() != getAlignment())
723     OS << "(align=" << getBaseAlignment() << ")";
724 
725   if (getOffset() != 0)
726     OS << "+" << getOffset();
727   OS << "]";
728 
729   // Print the alignment of the reference.
730   if (getBaseAlignment() != getAlignment() || getBaseAlignment() != getSize())
731     OS << "(align=" << getAlignment() << ")";
732 
733   // Print TBAA info.
734   if (const MDNode *TBAAInfo = getAAInfo().TBAA) {
735     OS << "(tbaa=";
736     if (TBAAInfo->getNumOperands() > 0)
737       TBAAInfo->getOperand(0)->printAsOperand(OS, MST);
738     else
739       OS << "<unknown>";
740     OS << ")";
741   }
742 
743   // Print AA scope info.
744   if (const MDNode *ScopeInfo = getAAInfo().Scope) {
745     OS << "(alias.scope=";
746     if (ScopeInfo->getNumOperands() > 0)
747       for (unsigned i = 0, ie = ScopeInfo->getNumOperands(); i != ie; ++i) {
748         ScopeInfo->getOperand(i)->printAsOperand(OS, MST);
749         if (i != ie-1)
750           OS << ",";
751       }
752     else
753       OS << "<unknown>";
754     OS << ")";
755   }
756 
757   // Print AA noalias scope info.
758   if (const MDNode *NoAliasInfo = getAAInfo().NoAlias) {
759     OS << "(noalias=";
760     if (NoAliasInfo->getNumOperands() > 0)
761       for (unsigned i = 0, ie = NoAliasInfo->getNumOperands(); i != ie; ++i) {
762         NoAliasInfo->getOperand(i)->printAsOperand(OS, MST);
763         if (i != ie-1)
764           OS << ",";
765       }
766     else
767       OS << "<unknown>";
768     OS << ")";
769   }
770 
771   if (isNonTemporal())
772     OS << "(nontemporal)";
773   if (isDereferenceable())
774     OS << "(dereferenceable)";
775   if (isInvariant())
776     OS << "(invariant)";
777 }
778 
779 //===----------------------------------------------------------------------===//
780 // MachineInstr Implementation
781 //===----------------------------------------------------------------------===//
782 
783 void MachineInstr::addImplicitDefUseOperands(MachineFunction &MF) {
784   if (MCID->ImplicitDefs)
785     for (const MCPhysReg *ImpDefs = MCID->getImplicitDefs(); *ImpDefs;
786            ++ImpDefs)
787       addOperand(MF, MachineOperand::CreateReg(*ImpDefs, true, true));
788   if (MCID->ImplicitUses)
789     for (const MCPhysReg *ImpUses = MCID->getImplicitUses(); *ImpUses;
790            ++ImpUses)
791       addOperand(MF, MachineOperand::CreateReg(*ImpUses, false, true));
792 }
793 
794 /// MachineInstr ctor - This constructor creates a MachineInstr and adds the
795 /// implicit operands. It reserves space for the number of operands specified by
796 /// the MCInstrDesc.
797 MachineInstr::MachineInstr(MachineFunction &MF, const MCInstrDesc &tid,
798                            DebugLoc dl, bool NoImp)
799     : MCID(&tid), debugLoc(std::move(dl)) {
800   assert(debugLoc.hasTrivialDestructor() && "Expected trivial destructor");
801 
802   // Reserve space for the expected number of operands.
803   if (unsigned NumOps = MCID->getNumOperands() +
804     MCID->getNumImplicitDefs() + MCID->getNumImplicitUses()) {
805     CapOperands = OperandCapacity::get(NumOps);
806     Operands = MF.allocateOperandArray(CapOperands);
807   }
808 
809   if (!NoImp)
810     addImplicitDefUseOperands(MF);
811 }
812 
813 /// MachineInstr ctor - Copies MachineInstr arg exactly
814 ///
815 MachineInstr::MachineInstr(MachineFunction &MF, const MachineInstr &MI)
816     : MCID(&MI.getDesc()), NumMemRefs(MI.NumMemRefs), MemRefs(MI.MemRefs),
817       debugLoc(MI.getDebugLoc()) {
818   assert(debugLoc.hasTrivialDestructor() && "Expected trivial destructor");
819 
820   CapOperands = OperandCapacity::get(MI.getNumOperands());
821   Operands = MF.allocateOperandArray(CapOperands);
822 
823   // Copy operands.
824   for (const MachineOperand &MO : MI.operands())
825     addOperand(MF, MO);
826 
827   // Copy all the sensible flags.
828   setFlags(MI.Flags);
829 }
830 
831 /// getRegInfo - If this instruction is embedded into a MachineFunction,
832 /// return the MachineRegisterInfo object for the current function, otherwise
833 /// return null.
834 MachineRegisterInfo *MachineInstr::getRegInfo() {
835   if (MachineBasicBlock *MBB = getParent())
836     return &MBB->getParent()->getRegInfo();
837   return nullptr;
838 }
839 
840 /// RemoveRegOperandsFromUseLists - Unlink all of the register operands in
841 /// this instruction from their respective use lists.  This requires that the
842 /// operands already be on their use lists.
843 void MachineInstr::RemoveRegOperandsFromUseLists(MachineRegisterInfo &MRI) {
844   for (MachineOperand &MO : operands())
845     if (MO.isReg())
846       MRI.removeRegOperandFromUseList(&MO);
847 }
848 
849 /// AddRegOperandsToUseLists - Add all of the register operands in
850 /// this instruction from their respective use lists.  This requires that the
851 /// operands not be on their use lists yet.
852 void MachineInstr::AddRegOperandsToUseLists(MachineRegisterInfo &MRI) {
853   for (MachineOperand &MO : operands())
854     if (MO.isReg())
855       MRI.addRegOperandToUseList(&MO);
856 }
857 
858 void MachineInstr::addOperand(const MachineOperand &Op) {
859   MachineBasicBlock *MBB = getParent();
860   assert(MBB && "Use MachineInstrBuilder to add operands to dangling instrs");
861   MachineFunction *MF = MBB->getParent();
862   assert(MF && "Use MachineInstrBuilder to add operands to dangling instrs");
863   addOperand(*MF, Op);
864 }
865 
866 /// Move NumOps MachineOperands from Src to Dst, with support for overlapping
867 /// ranges. If MRI is non-null also update use-def chains.
868 static void moveOperands(MachineOperand *Dst, MachineOperand *Src,
869                          unsigned NumOps, MachineRegisterInfo *MRI) {
870   if (MRI)
871     return MRI->moveOperands(Dst, Src, NumOps);
872 
873   // MachineOperand is a trivially copyable type so we can just use memmove.
874   std::memmove(Dst, Src, NumOps * sizeof(MachineOperand));
875 }
876 
877 /// addOperand - Add the specified operand to the instruction.  If it is an
878 /// implicit operand, it is added to the end of the operand list.  If it is
879 /// an explicit operand it is added at the end of the explicit operand list
880 /// (before the first implicit operand).
881 void MachineInstr::addOperand(MachineFunction &MF, const MachineOperand &Op) {
882   assert(MCID && "Cannot add operands before providing an instr descriptor");
883 
884   // Check if we're adding one of our existing operands.
885   if (&Op >= Operands && &Op < Operands + NumOperands) {
886     // This is unusual: MI->addOperand(MI->getOperand(i)).
887     // If adding Op requires reallocating or moving existing operands around,
888     // the Op reference could go stale. Support it by copying Op.
889     MachineOperand CopyOp(Op);
890     return addOperand(MF, CopyOp);
891   }
892 
893   // Find the insert location for the new operand.  Implicit registers go at
894   // the end, everything else goes before the implicit regs.
895   //
896   // FIXME: Allow mixed explicit and implicit operands on inline asm.
897   // InstrEmitter::EmitSpecialNode() is marking inline asm clobbers as
898   // implicit-defs, but they must not be moved around.  See the FIXME in
899   // InstrEmitter.cpp.
900   unsigned OpNo = getNumOperands();
901   bool isImpReg = Op.isReg() && Op.isImplicit();
902   if (!isImpReg && !isInlineAsm()) {
903     while (OpNo && Operands[OpNo-1].isReg() && Operands[OpNo-1].isImplicit()) {
904       --OpNo;
905       assert(!Operands[OpNo].isTied() && "Cannot move tied operands");
906     }
907   }
908 
909 #ifndef NDEBUG
910   bool isMetaDataOp = Op.getType() == MachineOperand::MO_Metadata;
911   // OpNo now points as the desired insertion point.  Unless this is a variadic
912   // instruction, only implicit regs are allowed beyond MCID->getNumOperands().
913   // RegMask operands go between the explicit and implicit operands.
914   assert((isImpReg || Op.isRegMask() || MCID->isVariadic() ||
915           OpNo < MCID->getNumOperands() || isMetaDataOp) &&
916          "Trying to add an operand to a machine instr that is already done!");
917 #endif
918 
919   MachineRegisterInfo *MRI = getRegInfo();
920 
921   // Determine if the Operands array needs to be reallocated.
922   // Save the old capacity and operand array.
923   OperandCapacity OldCap = CapOperands;
924   MachineOperand *OldOperands = Operands;
925   if (!OldOperands || OldCap.getSize() == getNumOperands()) {
926     CapOperands = OldOperands ? OldCap.getNext() : OldCap.get(1);
927     Operands = MF.allocateOperandArray(CapOperands);
928     // Move the operands before the insertion point.
929     if (OpNo)
930       moveOperands(Operands, OldOperands, OpNo, MRI);
931   }
932 
933   // Move the operands following the insertion point.
934   if (OpNo != NumOperands)
935     moveOperands(Operands + OpNo + 1, OldOperands + OpNo, NumOperands - OpNo,
936                  MRI);
937   ++NumOperands;
938 
939   // Deallocate the old operand array.
940   if (OldOperands != Operands && OldOperands)
941     MF.deallocateOperandArray(OldCap, OldOperands);
942 
943   // Copy Op into place. It still needs to be inserted into the MRI use lists.
944   MachineOperand *NewMO = new (Operands + OpNo) MachineOperand(Op);
945   NewMO->ParentMI = this;
946 
947   // When adding a register operand, tell MRI about it.
948   if (NewMO->isReg()) {
949     // Ensure isOnRegUseList() returns false, regardless of Op's status.
950     NewMO->Contents.Reg.Prev = nullptr;
951     // Ignore existing ties. This is not a property that can be copied.
952     NewMO->TiedTo = 0;
953     // Add the new operand to MRI, but only for instructions in an MBB.
954     if (MRI)
955       MRI->addRegOperandToUseList(NewMO);
956     // The MCID operand information isn't accurate until we start adding
957     // explicit operands. The implicit operands are added first, then the
958     // explicits are inserted before them.
959     if (!isImpReg) {
960       // Tie uses to defs as indicated in MCInstrDesc.
961       if (NewMO->isUse()) {
962         int DefIdx = MCID->getOperandConstraint(OpNo, MCOI::TIED_TO);
963         if (DefIdx != -1)
964           tieOperands(DefIdx, OpNo);
965       }
966       // If the register operand is flagged as early, mark the operand as such.
967       if (MCID->getOperandConstraint(OpNo, MCOI::EARLY_CLOBBER) != -1)
968         NewMO->setIsEarlyClobber(true);
969     }
970   }
971 }
972 
973 /// RemoveOperand - Erase an operand  from an instruction, leaving it with one
974 /// fewer operand than it started with.
975 ///
976 void MachineInstr::RemoveOperand(unsigned OpNo) {
977   assert(OpNo < getNumOperands() && "Invalid operand number");
978   untieRegOperand(OpNo);
979 
980 #ifndef NDEBUG
981   // Moving tied operands would break the ties.
982   for (unsigned i = OpNo + 1, e = getNumOperands(); i != e; ++i)
983     if (Operands[i].isReg())
984       assert(!Operands[i].isTied() && "Cannot move tied operands");
985 #endif
986 
987   MachineRegisterInfo *MRI = getRegInfo();
988   if (MRI && Operands[OpNo].isReg())
989     MRI->removeRegOperandFromUseList(Operands + OpNo);
990 
991   // Don't call the MachineOperand destructor. A lot of this code depends on
992   // MachineOperand having a trivial destructor anyway, and adding a call here
993   // wouldn't make it 'destructor-correct'.
994 
995   if (unsigned N = NumOperands - 1 - OpNo)
996     moveOperands(Operands + OpNo, Operands + OpNo + 1, N, MRI);
997   --NumOperands;
998 }
999 
1000 /// addMemOperand - Add a MachineMemOperand to the machine instruction.
1001 /// This function should be used only occasionally. The setMemRefs function
1002 /// is the primary method for setting up a MachineInstr's MemRefs list.
1003 void MachineInstr::addMemOperand(MachineFunction &MF,
1004                                  MachineMemOperand *MO) {
1005   mmo_iterator OldMemRefs = MemRefs;
1006   unsigned OldNumMemRefs = NumMemRefs;
1007 
1008   unsigned NewNum = NumMemRefs + 1;
1009   mmo_iterator NewMemRefs = MF.allocateMemRefsArray(NewNum);
1010 
1011   std::copy(OldMemRefs, OldMemRefs + OldNumMemRefs, NewMemRefs);
1012   NewMemRefs[NewNum - 1] = MO;
1013   setMemRefs(NewMemRefs, NewMemRefs + NewNum);
1014 }
1015 
1016 /// Check to see if the MMOs pointed to by the two MemRefs arrays are
1017 /// identical.
1018 static bool hasIdenticalMMOs(const MachineInstr &MI1, const MachineInstr &MI2) {
1019   auto I1 = MI1.memoperands_begin(), E1 = MI1.memoperands_end();
1020   auto I2 = MI2.memoperands_begin(), E2 = MI2.memoperands_end();
1021   if ((E1 - I1) != (E2 - I2))
1022     return false;
1023   for (; I1 != E1; ++I1, ++I2) {
1024     if (**I1 != **I2)
1025       return false;
1026   }
1027   return true;
1028 }
1029 
1030 std::pair<MachineInstr::mmo_iterator, unsigned>
1031 MachineInstr::mergeMemRefsWith(const MachineInstr& Other) {
1032 
1033   // If either of the incoming memrefs are empty, we must be conservative and
1034   // treat this as if we've exhausted our space for memrefs and dropped them.
1035   if (memoperands_empty() || Other.memoperands_empty())
1036     return std::make_pair(nullptr, 0);
1037 
1038   // If both instructions have identical memrefs, we don't need to merge them.
1039   // Since many instructions have a single memref, and we tend to merge things
1040   // like pairs of loads from the same location, this catches a large number of
1041   // cases in practice.
1042   if (hasIdenticalMMOs(*this, Other))
1043     return std::make_pair(MemRefs, NumMemRefs);
1044 
1045   // TODO: consider uniquing elements within the operand lists to reduce
1046   // space usage and fall back to conservative information less often.
1047   size_t CombinedNumMemRefs = NumMemRefs + Other.NumMemRefs;
1048 
1049   // If we don't have enough room to store this many memrefs, be conservative
1050   // and drop them.  Otherwise, we'd fail asserts when trying to add them to
1051   // the new instruction.
1052   if (CombinedNumMemRefs != uint8_t(CombinedNumMemRefs))
1053     return std::make_pair(nullptr, 0);
1054 
1055   MachineFunction *MF = getParent()->getParent();
1056   mmo_iterator MemBegin = MF->allocateMemRefsArray(CombinedNumMemRefs);
1057   mmo_iterator MemEnd = std::copy(memoperands_begin(), memoperands_end(),
1058                                   MemBegin);
1059   MemEnd = std::copy(Other.memoperands_begin(), Other.memoperands_end(),
1060                      MemEnd);
1061   assert(MemEnd - MemBegin == (ptrdiff_t)CombinedNumMemRefs &&
1062          "missing memrefs");
1063 
1064   return std::make_pair(MemBegin, CombinedNumMemRefs);
1065 }
1066 
1067 bool MachineInstr::hasPropertyInBundle(unsigned Mask, QueryType Type) const {
1068   assert(!isBundledWithPred() && "Must be called on bundle header");
1069   for (MachineBasicBlock::const_instr_iterator MII = getIterator();; ++MII) {
1070     if (MII->getDesc().getFlags() & Mask) {
1071       if (Type == AnyInBundle)
1072         return true;
1073     } else {
1074       if (Type == AllInBundle && !MII->isBundle())
1075         return false;
1076     }
1077     // This was the last instruction in the bundle.
1078     if (!MII->isBundledWithSucc())
1079       return Type == AllInBundle;
1080   }
1081 }
1082 
1083 bool MachineInstr::isIdenticalTo(const MachineInstr &Other,
1084                                  MICheckType Check) const {
1085   // If opcodes or number of operands are not the same then the two
1086   // instructions are obviously not identical.
1087   if (Other.getOpcode() != getOpcode() ||
1088       Other.getNumOperands() != getNumOperands())
1089     return false;
1090 
1091   if (isBundle()) {
1092     // We have passed the test above that both instructions have the same
1093     // opcode, so we know that both instructions are bundles here. Let's compare
1094     // MIs inside the bundle.
1095     assert(Other.isBundle() && "Expected that both instructions are bundles.");
1096     MachineBasicBlock::const_instr_iterator I1 = getIterator();
1097     MachineBasicBlock::const_instr_iterator I2 = Other.getIterator();
1098     // Loop until we analysed the last intruction inside at least one of the
1099     // bundles.
1100     while (I1->isBundledWithSucc() && I2->isBundledWithSucc()) {
1101       ++I1;
1102       ++I2;
1103       if (!I1->isIdenticalTo(*I2, Check))
1104         return false;
1105     }
1106     // If we've reached the end of just one of the two bundles, but not both,
1107     // the instructions are not identical.
1108     if (I1->isBundledWithSucc() || I2->isBundledWithSucc())
1109       return false;
1110   }
1111 
1112   // Check operands to make sure they match.
1113   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1114     const MachineOperand &MO = getOperand(i);
1115     const MachineOperand &OMO = Other.getOperand(i);
1116     if (!MO.isReg()) {
1117       if (!MO.isIdenticalTo(OMO))
1118         return false;
1119       continue;
1120     }
1121 
1122     // Clients may or may not want to ignore defs when testing for equality.
1123     // For example, machine CSE pass only cares about finding common
1124     // subexpressions, so it's safe to ignore virtual register defs.
1125     if (MO.isDef()) {
1126       if (Check == IgnoreDefs)
1127         continue;
1128       else if (Check == IgnoreVRegDefs) {
1129         if (TargetRegisterInfo::isPhysicalRegister(MO.getReg()) ||
1130             TargetRegisterInfo::isPhysicalRegister(OMO.getReg()))
1131           if (MO.getReg() != OMO.getReg())
1132             return false;
1133       } else {
1134         if (!MO.isIdenticalTo(OMO))
1135           return false;
1136         if (Check == CheckKillDead && MO.isDead() != OMO.isDead())
1137           return false;
1138       }
1139     } else {
1140       if (!MO.isIdenticalTo(OMO))
1141         return false;
1142       if (Check == CheckKillDead && MO.isKill() != OMO.isKill())
1143         return false;
1144     }
1145   }
1146   // If DebugLoc does not match then two dbg.values are not identical.
1147   if (isDebugValue())
1148     if (getDebugLoc() && Other.getDebugLoc() &&
1149         getDebugLoc() != Other.getDebugLoc())
1150       return false;
1151   return true;
1152 }
1153 
1154 MachineInstr *MachineInstr::removeFromParent() {
1155   assert(getParent() && "Not embedded in a basic block!");
1156   return getParent()->remove(this);
1157 }
1158 
1159 MachineInstr *MachineInstr::removeFromBundle() {
1160   assert(getParent() && "Not embedded in a basic block!");
1161   return getParent()->remove_instr(this);
1162 }
1163 
1164 void MachineInstr::eraseFromParent() {
1165   assert(getParent() && "Not embedded in a basic block!");
1166   getParent()->erase(this);
1167 }
1168 
1169 void MachineInstr::eraseFromParentAndMarkDBGValuesForRemoval() {
1170   assert(getParent() && "Not embedded in a basic block!");
1171   MachineBasicBlock *MBB = getParent();
1172   MachineFunction *MF = MBB->getParent();
1173   assert(MF && "Not embedded in a function!");
1174 
1175   MachineInstr *MI = (MachineInstr *)this;
1176   MachineRegisterInfo &MRI = MF->getRegInfo();
1177 
1178   for (const MachineOperand &MO : MI->operands()) {
1179     if (!MO.isReg() || !MO.isDef())
1180       continue;
1181     unsigned Reg = MO.getReg();
1182     if (!TargetRegisterInfo::isVirtualRegister(Reg))
1183       continue;
1184     MRI.markUsesInDebugValueAsUndef(Reg);
1185   }
1186   MI->eraseFromParent();
1187 }
1188 
1189 void MachineInstr::eraseFromBundle() {
1190   assert(getParent() && "Not embedded in a basic block!");
1191   getParent()->erase_instr(this);
1192 }
1193 
1194 /// getNumExplicitOperands - Returns the number of non-implicit operands.
1195 ///
1196 unsigned MachineInstr::getNumExplicitOperands() const {
1197   unsigned NumOperands = MCID->getNumOperands();
1198   if (!MCID->isVariadic())
1199     return NumOperands;
1200 
1201   for (unsigned i = NumOperands, e = getNumOperands(); i != e; ++i) {
1202     const MachineOperand &MO = getOperand(i);
1203     if (!MO.isReg() || !MO.isImplicit())
1204       NumOperands++;
1205   }
1206   return NumOperands;
1207 }
1208 
1209 void MachineInstr::bundleWithPred() {
1210   assert(!isBundledWithPred() && "MI is already bundled with its predecessor");
1211   setFlag(BundledPred);
1212   MachineBasicBlock::instr_iterator Pred = getIterator();
1213   --Pred;
1214   assert(!Pred->isBundledWithSucc() && "Inconsistent bundle flags");
1215   Pred->setFlag(BundledSucc);
1216 }
1217 
1218 void MachineInstr::bundleWithSucc() {
1219   assert(!isBundledWithSucc() && "MI is already bundled with its successor");
1220   setFlag(BundledSucc);
1221   MachineBasicBlock::instr_iterator Succ = getIterator();
1222   ++Succ;
1223   assert(!Succ->isBundledWithPred() && "Inconsistent bundle flags");
1224   Succ->setFlag(BundledPred);
1225 }
1226 
1227 void MachineInstr::unbundleFromPred() {
1228   assert(isBundledWithPred() && "MI isn't bundled with its predecessor");
1229   clearFlag(BundledPred);
1230   MachineBasicBlock::instr_iterator Pred = getIterator();
1231   --Pred;
1232   assert(Pred->isBundledWithSucc() && "Inconsistent bundle flags");
1233   Pred->clearFlag(BundledSucc);
1234 }
1235 
1236 void MachineInstr::unbundleFromSucc() {
1237   assert(isBundledWithSucc() && "MI isn't bundled with its successor");
1238   clearFlag(BundledSucc);
1239   MachineBasicBlock::instr_iterator Succ = getIterator();
1240   ++Succ;
1241   assert(Succ->isBundledWithPred() && "Inconsistent bundle flags");
1242   Succ->clearFlag(BundledPred);
1243 }
1244 
1245 bool MachineInstr::isStackAligningInlineAsm() const {
1246   if (isInlineAsm()) {
1247     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1248     if (ExtraInfo & InlineAsm::Extra_IsAlignStack)
1249       return true;
1250   }
1251   return false;
1252 }
1253 
1254 InlineAsm::AsmDialect MachineInstr::getInlineAsmDialect() const {
1255   assert(isInlineAsm() && "getInlineAsmDialect() only works for inline asms!");
1256   unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1257   return InlineAsm::AsmDialect((ExtraInfo & InlineAsm::Extra_AsmDialect) != 0);
1258 }
1259 
1260 int MachineInstr::findInlineAsmFlagIdx(unsigned OpIdx,
1261                                        unsigned *GroupNo) const {
1262   assert(isInlineAsm() && "Expected an inline asm instruction");
1263   assert(OpIdx < getNumOperands() && "OpIdx out of range");
1264 
1265   // Ignore queries about the initial operands.
1266   if (OpIdx < InlineAsm::MIOp_FirstOperand)
1267     return -1;
1268 
1269   unsigned Group = 0;
1270   unsigned NumOps;
1271   for (unsigned i = InlineAsm::MIOp_FirstOperand, e = getNumOperands(); i < e;
1272        i += NumOps) {
1273     const MachineOperand &FlagMO = getOperand(i);
1274     // If we reach the implicit register operands, stop looking.
1275     if (!FlagMO.isImm())
1276       return -1;
1277     NumOps = 1 + InlineAsm::getNumOperandRegisters(FlagMO.getImm());
1278     if (i + NumOps > OpIdx) {
1279       if (GroupNo)
1280         *GroupNo = Group;
1281       return i;
1282     }
1283     ++Group;
1284   }
1285   return -1;
1286 }
1287 
1288 const DILocalVariable *MachineInstr::getDebugVariable() const {
1289   assert(isDebugValue() && "not a DBG_VALUE");
1290   return cast<DILocalVariable>(getOperand(2).getMetadata());
1291 }
1292 
1293 const DIExpression *MachineInstr::getDebugExpression() const {
1294   assert(isDebugValue() && "not a DBG_VALUE");
1295   return cast<DIExpression>(getOperand(3).getMetadata());
1296 }
1297 
1298 const TargetRegisterClass*
1299 MachineInstr::getRegClassConstraint(unsigned OpIdx,
1300                                     const TargetInstrInfo *TII,
1301                                     const TargetRegisterInfo *TRI) const {
1302   assert(getParent() && "Can't have an MBB reference here!");
1303   assert(getParent()->getParent() && "Can't have an MF reference here!");
1304   const MachineFunction &MF = *getParent()->getParent();
1305 
1306   // Most opcodes have fixed constraints in their MCInstrDesc.
1307   if (!isInlineAsm())
1308     return TII->getRegClass(getDesc(), OpIdx, TRI, MF);
1309 
1310   if (!getOperand(OpIdx).isReg())
1311     return nullptr;
1312 
1313   // For tied uses on inline asm, get the constraint from the def.
1314   unsigned DefIdx;
1315   if (getOperand(OpIdx).isUse() && isRegTiedToDefOperand(OpIdx, &DefIdx))
1316     OpIdx = DefIdx;
1317 
1318   // Inline asm stores register class constraints in the flag word.
1319   int FlagIdx = findInlineAsmFlagIdx(OpIdx);
1320   if (FlagIdx < 0)
1321     return nullptr;
1322 
1323   unsigned Flag = getOperand(FlagIdx).getImm();
1324   unsigned RCID;
1325   if ((InlineAsm::getKind(Flag) == InlineAsm::Kind_RegUse ||
1326        InlineAsm::getKind(Flag) == InlineAsm::Kind_RegDef ||
1327        InlineAsm::getKind(Flag) == InlineAsm::Kind_RegDefEarlyClobber) &&
1328       InlineAsm::hasRegClassConstraint(Flag, RCID))
1329     return TRI->getRegClass(RCID);
1330 
1331   // Assume that all registers in a memory operand are pointers.
1332   if (InlineAsm::getKind(Flag) == InlineAsm::Kind_Mem)
1333     return TRI->getPointerRegClass(MF);
1334 
1335   return nullptr;
1336 }
1337 
1338 const TargetRegisterClass *MachineInstr::getRegClassConstraintEffectForVReg(
1339     unsigned Reg, const TargetRegisterClass *CurRC, const TargetInstrInfo *TII,
1340     const TargetRegisterInfo *TRI, bool ExploreBundle) const {
1341   // Check every operands inside the bundle if we have
1342   // been asked to.
1343   if (ExploreBundle)
1344     for (ConstMIBundleOperands OpndIt(*this); OpndIt.isValid() && CurRC;
1345          ++OpndIt)
1346       CurRC = OpndIt->getParent()->getRegClassConstraintEffectForVRegImpl(
1347           OpndIt.getOperandNo(), Reg, CurRC, TII, TRI);
1348   else
1349     // Otherwise, just check the current operands.
1350     for (unsigned i = 0, e = NumOperands; i < e && CurRC; ++i)
1351       CurRC = getRegClassConstraintEffectForVRegImpl(i, Reg, CurRC, TII, TRI);
1352   return CurRC;
1353 }
1354 
1355 const TargetRegisterClass *MachineInstr::getRegClassConstraintEffectForVRegImpl(
1356     unsigned OpIdx, unsigned Reg, const TargetRegisterClass *CurRC,
1357     const TargetInstrInfo *TII, const TargetRegisterInfo *TRI) const {
1358   assert(CurRC && "Invalid initial register class");
1359   // Check if Reg is constrained by some of its use/def from MI.
1360   const MachineOperand &MO = getOperand(OpIdx);
1361   if (!MO.isReg() || MO.getReg() != Reg)
1362     return CurRC;
1363   // If yes, accumulate the constraints through the operand.
1364   return getRegClassConstraintEffect(OpIdx, CurRC, TII, TRI);
1365 }
1366 
1367 const TargetRegisterClass *MachineInstr::getRegClassConstraintEffect(
1368     unsigned OpIdx, const TargetRegisterClass *CurRC,
1369     const TargetInstrInfo *TII, const TargetRegisterInfo *TRI) const {
1370   const TargetRegisterClass *OpRC = getRegClassConstraint(OpIdx, TII, TRI);
1371   const MachineOperand &MO = getOperand(OpIdx);
1372   assert(MO.isReg() &&
1373          "Cannot get register constraints for non-register operand");
1374   assert(CurRC && "Invalid initial register class");
1375   if (unsigned SubIdx = MO.getSubReg()) {
1376     if (OpRC)
1377       CurRC = TRI->getMatchingSuperRegClass(CurRC, OpRC, SubIdx);
1378     else
1379       CurRC = TRI->getSubClassWithSubReg(CurRC, SubIdx);
1380   } else if (OpRC)
1381     CurRC = TRI->getCommonSubClass(CurRC, OpRC);
1382   return CurRC;
1383 }
1384 
1385 /// Return the number of instructions inside the MI bundle, not counting the
1386 /// header instruction.
1387 unsigned MachineInstr::getBundleSize() const {
1388   MachineBasicBlock::const_instr_iterator I = getIterator();
1389   unsigned Size = 0;
1390   while (I->isBundledWithSucc()) {
1391     ++Size;
1392     ++I;
1393   }
1394   return Size;
1395 }
1396 
1397 /// Returns true if the MachineInstr has an implicit-use operand of exactly
1398 /// the given register (not considering sub/super-registers).
1399 bool MachineInstr::hasRegisterImplicitUseOperand(unsigned Reg) const {
1400   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1401     const MachineOperand &MO = getOperand(i);
1402     if (MO.isReg() && MO.isUse() && MO.isImplicit() && MO.getReg() == Reg)
1403       return true;
1404   }
1405   return false;
1406 }
1407 
1408 /// findRegisterUseOperandIdx() - Returns the MachineOperand that is a use of
1409 /// the specific register or -1 if it is not found. It further tightens
1410 /// the search criteria to a use that kills the register if isKill is true.
1411 int MachineInstr::findRegisterUseOperandIdx(
1412     unsigned Reg, bool isKill, const TargetRegisterInfo *TRI) const {
1413   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1414     const MachineOperand &MO = getOperand(i);
1415     if (!MO.isReg() || !MO.isUse())
1416       continue;
1417     unsigned MOReg = MO.getReg();
1418     if (!MOReg)
1419       continue;
1420     if (MOReg == Reg || (TRI && TargetRegisterInfo::isPhysicalRegister(MOReg) &&
1421                          TargetRegisterInfo::isPhysicalRegister(Reg) &&
1422                          TRI->isSubRegister(MOReg, Reg)))
1423       if (!isKill || MO.isKill())
1424         return i;
1425   }
1426   return -1;
1427 }
1428 
1429 /// readsWritesVirtualRegister - Return a pair of bools (reads, writes)
1430 /// indicating if this instruction reads or writes Reg. This also considers
1431 /// partial defines.
1432 std::pair<bool,bool>
1433 MachineInstr::readsWritesVirtualRegister(unsigned Reg,
1434                                          SmallVectorImpl<unsigned> *Ops) const {
1435   bool PartDef = false; // Partial redefine.
1436   bool FullDef = false; // Full define.
1437   bool Use = false;
1438 
1439   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1440     const MachineOperand &MO = getOperand(i);
1441     if (!MO.isReg() || MO.getReg() != Reg)
1442       continue;
1443     if (Ops)
1444       Ops->push_back(i);
1445     if (MO.isUse())
1446       Use |= !MO.isUndef();
1447     else if (MO.getSubReg() && !MO.isUndef())
1448       // A partial <def,undef> doesn't count as reading the register.
1449       PartDef = true;
1450     else
1451       FullDef = true;
1452   }
1453   // A partial redefine uses Reg unless there is also a full define.
1454   return std::make_pair(Use || (PartDef && !FullDef), PartDef || FullDef);
1455 }
1456 
1457 /// findRegisterDefOperandIdx() - Returns the operand index that is a def of
1458 /// the specified register or -1 if it is not found. If isDead is true, defs
1459 /// that are not dead are skipped. If TargetRegisterInfo is non-null, then it
1460 /// also checks if there is a def of a super-register.
1461 int
1462 MachineInstr::findRegisterDefOperandIdx(unsigned Reg, bool isDead, bool Overlap,
1463                                         const TargetRegisterInfo *TRI) const {
1464   bool isPhys = TargetRegisterInfo::isPhysicalRegister(Reg);
1465   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1466     const MachineOperand &MO = getOperand(i);
1467     // Accept regmask operands when Overlap is set.
1468     // Ignore them when looking for a specific def operand (Overlap == false).
1469     if (isPhys && Overlap && MO.isRegMask() && MO.clobbersPhysReg(Reg))
1470       return i;
1471     if (!MO.isReg() || !MO.isDef())
1472       continue;
1473     unsigned MOReg = MO.getReg();
1474     bool Found = (MOReg == Reg);
1475     if (!Found && TRI && isPhys &&
1476         TargetRegisterInfo::isPhysicalRegister(MOReg)) {
1477       if (Overlap)
1478         Found = TRI->regsOverlap(MOReg, Reg);
1479       else
1480         Found = TRI->isSubRegister(MOReg, Reg);
1481     }
1482     if (Found && (!isDead || MO.isDead()))
1483       return i;
1484   }
1485   return -1;
1486 }
1487 
1488 /// findFirstPredOperandIdx() - Find the index of the first operand in the
1489 /// operand list that is used to represent the predicate. It returns -1 if
1490 /// none is found.
1491 int MachineInstr::findFirstPredOperandIdx() const {
1492   // Don't call MCID.findFirstPredOperandIdx() because this variant
1493   // is sometimes called on an instruction that's not yet complete, and
1494   // so the number of operands is less than the MCID indicates. In
1495   // particular, the PTX target does this.
1496   const MCInstrDesc &MCID = getDesc();
1497   if (MCID.isPredicable()) {
1498     for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
1499       if (MCID.OpInfo[i].isPredicate())
1500         return i;
1501   }
1502 
1503   return -1;
1504 }
1505 
1506 // MachineOperand::TiedTo is 4 bits wide.
1507 const unsigned TiedMax = 15;
1508 
1509 /// tieOperands - Mark operands at DefIdx and UseIdx as tied to each other.
1510 ///
1511 /// Use and def operands can be tied together, indicated by a non-zero TiedTo
1512 /// field. TiedTo can have these values:
1513 ///
1514 /// 0:              Operand is not tied to anything.
1515 /// 1 to TiedMax-1: Tied to getOperand(TiedTo-1).
1516 /// TiedMax:        Tied to an operand >= TiedMax-1.
1517 ///
1518 /// The tied def must be one of the first TiedMax operands on a normal
1519 /// instruction. INLINEASM instructions allow more tied defs.
1520 ///
1521 void MachineInstr::tieOperands(unsigned DefIdx, unsigned UseIdx) {
1522   MachineOperand &DefMO = getOperand(DefIdx);
1523   MachineOperand &UseMO = getOperand(UseIdx);
1524   assert(DefMO.isDef() && "DefIdx must be a def operand");
1525   assert(UseMO.isUse() && "UseIdx must be a use operand");
1526   assert(!DefMO.isTied() && "Def is already tied to another use");
1527   assert(!UseMO.isTied() && "Use is already tied to another def");
1528 
1529   if (DefIdx < TiedMax)
1530     UseMO.TiedTo = DefIdx + 1;
1531   else {
1532     // Inline asm can use the group descriptors to find tied operands, but on
1533     // normal instruction, the tied def must be within the first TiedMax
1534     // operands.
1535     assert(isInlineAsm() && "DefIdx out of range");
1536     UseMO.TiedTo = TiedMax;
1537   }
1538 
1539   // UseIdx can be out of range, we'll search for it in findTiedOperandIdx().
1540   DefMO.TiedTo = std::min(UseIdx + 1, TiedMax);
1541 }
1542 
1543 /// Given the index of a tied register operand, find the operand it is tied to.
1544 /// Defs are tied to uses and vice versa. Returns the index of the tied operand
1545 /// which must exist.
1546 unsigned MachineInstr::findTiedOperandIdx(unsigned OpIdx) const {
1547   const MachineOperand &MO = getOperand(OpIdx);
1548   assert(MO.isTied() && "Operand isn't tied");
1549 
1550   // Normally TiedTo is in range.
1551   if (MO.TiedTo < TiedMax)
1552     return MO.TiedTo - 1;
1553 
1554   // Uses on normal instructions can be out of range.
1555   if (!isInlineAsm()) {
1556     // Normal tied defs must be in the 0..TiedMax-1 range.
1557     if (MO.isUse())
1558       return TiedMax - 1;
1559     // MO is a def. Search for the tied use.
1560     for (unsigned i = TiedMax - 1, e = getNumOperands(); i != e; ++i) {
1561       const MachineOperand &UseMO = getOperand(i);
1562       if (UseMO.isReg() && UseMO.isUse() && UseMO.TiedTo == OpIdx + 1)
1563         return i;
1564     }
1565     llvm_unreachable("Can't find tied use");
1566   }
1567 
1568   // Now deal with inline asm by parsing the operand group descriptor flags.
1569   // Find the beginning of each operand group.
1570   SmallVector<unsigned, 8> GroupIdx;
1571   unsigned OpIdxGroup = ~0u;
1572   unsigned NumOps;
1573   for (unsigned i = InlineAsm::MIOp_FirstOperand, e = getNumOperands(); i < e;
1574        i += NumOps) {
1575     const MachineOperand &FlagMO = getOperand(i);
1576     assert(FlagMO.isImm() && "Invalid tied operand on inline asm");
1577     unsigned CurGroup = GroupIdx.size();
1578     GroupIdx.push_back(i);
1579     NumOps = 1 + InlineAsm::getNumOperandRegisters(FlagMO.getImm());
1580     // OpIdx belongs to this operand group.
1581     if (OpIdx > i && OpIdx < i + NumOps)
1582       OpIdxGroup = CurGroup;
1583     unsigned TiedGroup;
1584     if (!InlineAsm::isUseOperandTiedToDef(FlagMO.getImm(), TiedGroup))
1585       continue;
1586     // Operands in this group are tied to operands in TiedGroup which must be
1587     // earlier. Find the number of operands between the two groups.
1588     unsigned Delta = i - GroupIdx[TiedGroup];
1589 
1590     // OpIdx is a use tied to TiedGroup.
1591     if (OpIdxGroup == CurGroup)
1592       return OpIdx - Delta;
1593 
1594     // OpIdx is a def tied to this use group.
1595     if (OpIdxGroup == TiedGroup)
1596       return OpIdx + Delta;
1597   }
1598   llvm_unreachable("Invalid tied operand on inline asm");
1599 }
1600 
1601 /// clearKillInfo - Clears kill flags on all operands.
1602 ///
1603 void MachineInstr::clearKillInfo() {
1604   for (MachineOperand &MO : operands()) {
1605     if (MO.isReg() && MO.isUse())
1606       MO.setIsKill(false);
1607   }
1608 }
1609 
1610 void MachineInstr::substituteRegister(unsigned FromReg,
1611                                       unsigned ToReg,
1612                                       unsigned SubIdx,
1613                                       const TargetRegisterInfo &RegInfo) {
1614   if (TargetRegisterInfo::isPhysicalRegister(ToReg)) {
1615     if (SubIdx)
1616       ToReg = RegInfo.getSubReg(ToReg, SubIdx);
1617     for (MachineOperand &MO : operands()) {
1618       if (!MO.isReg() || MO.getReg() != FromReg)
1619         continue;
1620       MO.substPhysReg(ToReg, RegInfo);
1621     }
1622   } else {
1623     for (MachineOperand &MO : operands()) {
1624       if (!MO.isReg() || MO.getReg() != FromReg)
1625         continue;
1626       MO.substVirtReg(ToReg, SubIdx, RegInfo);
1627     }
1628   }
1629 }
1630 
1631 /// isSafeToMove - Return true if it is safe to move this instruction. If
1632 /// SawStore is set to true, it means that there is a store (or call) between
1633 /// the instruction's location and its intended destination.
1634 bool MachineInstr::isSafeToMove(AliasAnalysis *AA, bool &SawStore) const {
1635   // Ignore stuff that we obviously can't move.
1636   //
1637   // Treat volatile loads as stores. This is not strictly necessary for
1638   // volatiles, but it is required for atomic loads. It is not allowed to move
1639   // a load across an atomic load with Ordering > Monotonic.
1640   if (mayStore() || isCall() ||
1641       (mayLoad() && hasOrderedMemoryRef())) {
1642     SawStore = true;
1643     return false;
1644   }
1645 
1646   if (isPosition() || isDebugValue() || isTerminator() ||
1647       hasUnmodeledSideEffects())
1648     return false;
1649 
1650   // See if this instruction does a load.  If so, we have to guarantee that the
1651   // loaded value doesn't change between the load and the its intended
1652   // destination. The check for isInvariantLoad gives the targe the chance to
1653   // classify the load as always returning a constant, e.g. a constant pool
1654   // load.
1655   if (mayLoad() && !isDereferenceableInvariantLoad(AA))
1656     // Otherwise, this is a real load.  If there is a store between the load and
1657     // end of block, we can't move it.
1658     return !SawStore;
1659 
1660   return true;
1661 }
1662 
1663 bool MachineInstr::mayAlias(AliasAnalysis *AA, MachineInstr &Other,
1664                             bool UseTBAA) {
1665   const MachineFunction *MF = getParent()->getParent();
1666   const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
1667 
1668   // If neither instruction stores to memory, they can't alias in any
1669   // meaningful way, even if they read from the same address.
1670   if (!mayStore() && !Other.mayStore())
1671     return false;
1672 
1673   // Let the target decide if memory accesses cannot possibly overlap.
1674   if (TII->areMemAccessesTriviallyDisjoint(*this, Other, AA))
1675     return false;
1676 
1677   if (!AA)
1678     return true;
1679 
1680   // FIXME: Need to handle multiple memory operands to support all targets.
1681   if (!hasOneMemOperand() || !Other.hasOneMemOperand())
1682     return true;
1683 
1684   MachineMemOperand *MMOa = *memoperands_begin();
1685   MachineMemOperand *MMOb = *Other.memoperands_begin();
1686 
1687   if (!MMOa->getValue() || !MMOb->getValue())
1688     return true;
1689 
1690   // The following interface to AA is fashioned after DAGCombiner::isAlias
1691   // and operates with MachineMemOperand offset with some important
1692   // assumptions:
1693   //   - LLVM fundamentally assumes flat address spaces.
1694   //   - MachineOperand offset can *only* result from legalization and
1695   //     cannot affect queries other than the trivial case of overlap
1696   //     checking.
1697   //   - These offsets never wrap and never step outside
1698   //     of allocated objects.
1699   //   - There should never be any negative offsets here.
1700   //
1701   // FIXME: Modify API to hide this math from "user"
1702   // FIXME: Even before we go to AA we can reason locally about some
1703   // memory objects. It can save compile time, and possibly catch some
1704   // corner cases not currently covered.
1705 
1706   assert((MMOa->getOffset() >= 0) && "Negative MachineMemOperand offset");
1707   assert((MMOb->getOffset() >= 0) && "Negative MachineMemOperand offset");
1708 
1709   int64_t MinOffset = std::min(MMOa->getOffset(), MMOb->getOffset());
1710   int64_t Overlapa = MMOa->getSize() + MMOa->getOffset() - MinOffset;
1711   int64_t Overlapb = MMOb->getSize() + MMOb->getOffset() - MinOffset;
1712 
1713   AliasResult AAResult =
1714       AA->alias(MemoryLocation(MMOa->getValue(), Overlapa,
1715                                UseTBAA ? MMOa->getAAInfo() : AAMDNodes()),
1716                 MemoryLocation(MMOb->getValue(), Overlapb,
1717                                UseTBAA ? MMOb->getAAInfo() : AAMDNodes()));
1718 
1719   return (AAResult != NoAlias);
1720 }
1721 
1722 /// hasOrderedMemoryRef - Return true if this instruction may have an ordered
1723 /// or volatile memory reference, or if the information describing the memory
1724 /// reference is not available. Return false if it is known to have no ordered
1725 /// memory references.
1726 bool MachineInstr::hasOrderedMemoryRef() const {
1727   // An instruction known never to access memory won't have a volatile access.
1728   if (!mayStore() &&
1729       !mayLoad() &&
1730       !isCall() &&
1731       !hasUnmodeledSideEffects())
1732     return false;
1733 
1734   // Otherwise, if the instruction has no memory reference information,
1735   // conservatively assume it wasn't preserved.
1736   if (memoperands_empty())
1737     return true;
1738 
1739   // Check if any of our memory operands are ordered.
1740   return llvm::any_of(memoperands(), [](const MachineMemOperand *MMO) {
1741     return !MMO->isUnordered();
1742   });
1743 }
1744 
1745 /// isDereferenceableInvariantLoad - Return true if this instruction will never
1746 /// trap and is loading from a location whose value is invariant across a run of
1747 /// this function.
1748 bool MachineInstr::isDereferenceableInvariantLoad(AliasAnalysis *AA) const {
1749   // If the instruction doesn't load at all, it isn't an invariant load.
1750   if (!mayLoad())
1751     return false;
1752 
1753   // If the instruction has lost its memoperands, conservatively assume that
1754   // it may not be an invariant load.
1755   if (memoperands_empty())
1756     return false;
1757 
1758   const MachineFrameInfo &MFI = getParent()->getParent()->getFrameInfo();
1759 
1760   for (MachineMemOperand *MMO : memoperands()) {
1761     if (MMO->isVolatile()) return false;
1762     if (MMO->isStore()) return false;
1763     if (MMO->isInvariant() && MMO->isDereferenceable())
1764       continue;
1765 
1766     // A load from a constant PseudoSourceValue is invariant.
1767     if (const PseudoSourceValue *PSV = MMO->getPseudoValue())
1768       if (PSV->isConstant(&MFI))
1769         continue;
1770 
1771     if (const Value *V = MMO->getValue()) {
1772       // If we have an AliasAnalysis, ask it whether the memory is constant.
1773       if (AA &&
1774           AA->pointsToConstantMemory(
1775               MemoryLocation(V, MMO->getSize(), MMO->getAAInfo())))
1776         continue;
1777     }
1778 
1779     // Otherwise assume conservatively.
1780     return false;
1781   }
1782 
1783   // Everything checks out.
1784   return true;
1785 }
1786 
1787 /// isConstantValuePHI - If the specified instruction is a PHI that always
1788 /// merges together the same virtual register, return the register, otherwise
1789 /// return 0.
1790 unsigned MachineInstr::isConstantValuePHI() const {
1791   if (!isPHI())
1792     return 0;
1793   assert(getNumOperands() >= 3 &&
1794          "It's illegal to have a PHI without source operands");
1795 
1796   unsigned Reg = getOperand(1).getReg();
1797   for (unsigned i = 3, e = getNumOperands(); i < e; i += 2)
1798     if (getOperand(i).getReg() != Reg)
1799       return 0;
1800   return Reg;
1801 }
1802 
1803 bool MachineInstr::hasUnmodeledSideEffects() const {
1804   if (hasProperty(MCID::UnmodeledSideEffects))
1805     return true;
1806   if (isInlineAsm()) {
1807     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1808     if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
1809       return true;
1810   }
1811 
1812   return false;
1813 }
1814 
1815 bool MachineInstr::isLoadFoldBarrier() const {
1816   return mayStore() || isCall() || hasUnmodeledSideEffects();
1817 }
1818 
1819 /// allDefsAreDead - Return true if all the defs of this instruction are dead.
1820 ///
1821 bool MachineInstr::allDefsAreDead() const {
1822   for (const MachineOperand &MO : operands()) {
1823     if (!MO.isReg() || MO.isUse())
1824       continue;
1825     if (!MO.isDead())
1826       return false;
1827   }
1828   return true;
1829 }
1830 
1831 /// copyImplicitOps - Copy implicit register operands from specified
1832 /// instruction to this instruction.
1833 void MachineInstr::copyImplicitOps(MachineFunction &MF,
1834                                    const MachineInstr &MI) {
1835   for (unsigned i = MI.getDesc().getNumOperands(), e = MI.getNumOperands();
1836        i != e; ++i) {
1837     const MachineOperand &MO = MI.getOperand(i);
1838     if ((MO.isReg() && MO.isImplicit()) || MO.isRegMask())
1839       addOperand(MF, MO);
1840   }
1841 }
1842 
1843 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
1844 LLVM_DUMP_METHOD void MachineInstr::dump() const {
1845   dbgs() << "  ";
1846   print(dbgs());
1847 }
1848 #endif
1849 
1850 void MachineInstr::print(raw_ostream &OS, bool SkipOpers, bool SkipDebugLoc,
1851                          const TargetInstrInfo *TII) const {
1852   const Module *M = nullptr;
1853   if (const MachineBasicBlock *MBB = getParent())
1854     if (const MachineFunction *MF = MBB->getParent())
1855       M = MF->getFunction()->getParent();
1856 
1857   ModuleSlotTracker MST(M);
1858   print(OS, MST, SkipOpers, SkipDebugLoc, TII);
1859 }
1860 
1861 void MachineInstr::print(raw_ostream &OS, ModuleSlotTracker &MST,
1862                          bool SkipOpers, bool SkipDebugLoc,
1863                          const TargetInstrInfo *TII) const {
1864   // We can be a bit tidier if we know the MachineFunction.
1865   const MachineFunction *MF = nullptr;
1866   const TargetRegisterInfo *TRI = nullptr;
1867   const MachineRegisterInfo *MRI = nullptr;
1868   const TargetIntrinsicInfo *IntrinsicInfo = nullptr;
1869 
1870   if (const MachineBasicBlock *MBB = getParent()) {
1871     MF = MBB->getParent();
1872     if (MF) {
1873       MRI = &MF->getRegInfo();
1874       TRI = MF->getSubtarget().getRegisterInfo();
1875       if (!TII)
1876         TII = MF->getSubtarget().getInstrInfo();
1877       IntrinsicInfo = MF->getTarget().getIntrinsicInfo();
1878     }
1879   }
1880 
1881   // Save a list of virtual registers.
1882   SmallVector<unsigned, 8> VirtRegs;
1883 
1884   // Print explicitly defined operands on the left of an assignment syntax.
1885   unsigned StartOp = 0, e = getNumOperands();
1886   for (; StartOp < e && getOperand(StartOp).isReg() &&
1887          getOperand(StartOp).isDef() &&
1888          !getOperand(StartOp).isImplicit();
1889        ++StartOp) {
1890     if (StartOp != 0) OS << ", ";
1891     getOperand(StartOp).print(OS, MST, TRI, IntrinsicInfo);
1892     unsigned Reg = getOperand(StartOp).getReg();
1893     if (TargetRegisterInfo::isVirtualRegister(Reg)) {
1894       VirtRegs.push_back(Reg);
1895       LLT Ty = MRI ? MRI->getType(Reg) : LLT{};
1896       if (Ty.isValid())
1897         OS << '(' << Ty << ')';
1898     }
1899   }
1900 
1901   if (StartOp != 0)
1902     OS << " = ";
1903 
1904   // Print the opcode name.
1905   if (TII)
1906     OS << TII->getName(getOpcode());
1907   else
1908     OS << "UNKNOWN";
1909 
1910   if (SkipOpers)
1911     return;
1912 
1913   // Print the rest of the operands.
1914   bool FirstOp = true;
1915   unsigned AsmDescOp = ~0u;
1916   unsigned AsmOpCount = 0;
1917 
1918   if (isInlineAsm() && e >= InlineAsm::MIOp_FirstOperand) {
1919     // Print asm string.
1920     OS << " ";
1921     getOperand(InlineAsm::MIOp_AsmString).print(OS, MST, TRI);
1922 
1923     // Print HasSideEffects, MayLoad, MayStore, IsAlignStack
1924     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1925     if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
1926       OS << " [sideeffect]";
1927     if (ExtraInfo & InlineAsm::Extra_MayLoad)
1928       OS << " [mayload]";
1929     if (ExtraInfo & InlineAsm::Extra_MayStore)
1930       OS << " [maystore]";
1931     if (ExtraInfo & InlineAsm::Extra_IsConvergent)
1932       OS << " [isconvergent]";
1933     if (ExtraInfo & InlineAsm::Extra_IsAlignStack)
1934       OS << " [alignstack]";
1935     if (getInlineAsmDialect() == InlineAsm::AD_ATT)
1936       OS << " [attdialect]";
1937     if (getInlineAsmDialect() == InlineAsm::AD_Intel)
1938       OS << " [inteldialect]";
1939 
1940     StartOp = AsmDescOp = InlineAsm::MIOp_FirstOperand;
1941     FirstOp = false;
1942   }
1943 
1944   for (unsigned i = StartOp, e = getNumOperands(); i != e; ++i) {
1945     const MachineOperand &MO = getOperand(i);
1946 
1947     if (MO.isReg() && TargetRegisterInfo::isVirtualRegister(MO.getReg()))
1948       VirtRegs.push_back(MO.getReg());
1949 
1950     if (FirstOp) FirstOp = false; else OS << ",";
1951     OS << " ";
1952     if (i < getDesc().NumOperands) {
1953       const MCOperandInfo &MCOI = getDesc().OpInfo[i];
1954       if (MCOI.isPredicate())
1955         OS << "pred:";
1956       if (MCOI.isOptionalDef())
1957         OS << "opt:";
1958     }
1959     if (isDebugValue() && MO.isMetadata()) {
1960       // Pretty print DBG_VALUE instructions.
1961       auto *DIV = dyn_cast<DILocalVariable>(MO.getMetadata());
1962       if (DIV && !DIV->getName().empty())
1963         OS << "!\"" << DIV->getName() << '\"';
1964       else
1965         MO.print(OS, MST, TRI);
1966     } else if (TRI && (isInsertSubreg() || isRegSequence() ||
1967                        (isSubregToReg() && i == 3)) && MO.isImm()) {
1968       OS << TRI->getSubRegIndexName(MO.getImm());
1969     } else if (i == AsmDescOp && MO.isImm()) {
1970       // Pretty print the inline asm operand descriptor.
1971       OS << '$' << AsmOpCount++;
1972       unsigned Flag = MO.getImm();
1973       switch (InlineAsm::getKind(Flag)) {
1974       case InlineAsm::Kind_RegUse:             OS << ":[reguse"; break;
1975       case InlineAsm::Kind_RegDef:             OS << ":[regdef"; break;
1976       case InlineAsm::Kind_RegDefEarlyClobber: OS << ":[regdef-ec"; break;
1977       case InlineAsm::Kind_Clobber:            OS << ":[clobber"; break;
1978       case InlineAsm::Kind_Imm:                OS << ":[imm"; break;
1979       case InlineAsm::Kind_Mem:                OS << ":[mem"; break;
1980       default: OS << ":[??" << InlineAsm::getKind(Flag); break;
1981       }
1982 
1983       unsigned RCID = 0;
1984       if (!InlineAsm::isImmKind(Flag) && !InlineAsm::isMemKind(Flag) &&
1985           InlineAsm::hasRegClassConstraint(Flag, RCID)) {
1986         if (TRI) {
1987           OS << ':' << TRI->getRegClassName(TRI->getRegClass(RCID));
1988         } else
1989           OS << ":RC" << RCID;
1990       }
1991 
1992       if (InlineAsm::isMemKind(Flag)) {
1993         unsigned MCID = InlineAsm::getMemoryConstraintID(Flag);
1994         switch (MCID) {
1995         case InlineAsm::Constraint_es: OS << ":es"; break;
1996         case InlineAsm::Constraint_i:  OS << ":i"; break;
1997         case InlineAsm::Constraint_m:  OS << ":m"; break;
1998         case InlineAsm::Constraint_o:  OS << ":o"; break;
1999         case InlineAsm::Constraint_v:  OS << ":v"; break;
2000         case InlineAsm::Constraint_Q:  OS << ":Q"; break;
2001         case InlineAsm::Constraint_R:  OS << ":R"; break;
2002         case InlineAsm::Constraint_S:  OS << ":S"; break;
2003         case InlineAsm::Constraint_T:  OS << ":T"; break;
2004         case InlineAsm::Constraint_Um: OS << ":Um"; break;
2005         case InlineAsm::Constraint_Un: OS << ":Un"; break;
2006         case InlineAsm::Constraint_Uq: OS << ":Uq"; break;
2007         case InlineAsm::Constraint_Us: OS << ":Us"; break;
2008         case InlineAsm::Constraint_Ut: OS << ":Ut"; break;
2009         case InlineAsm::Constraint_Uv: OS << ":Uv"; break;
2010         case InlineAsm::Constraint_Uy: OS << ":Uy"; break;
2011         case InlineAsm::Constraint_X:  OS << ":X"; break;
2012         case InlineAsm::Constraint_Z:  OS << ":Z"; break;
2013         case InlineAsm::Constraint_ZC: OS << ":ZC"; break;
2014         case InlineAsm::Constraint_Zy: OS << ":Zy"; break;
2015         default: OS << ":?"; break;
2016         }
2017       }
2018 
2019       unsigned TiedTo = 0;
2020       if (InlineAsm::isUseOperandTiedToDef(Flag, TiedTo))
2021         OS << " tiedto:$" << TiedTo;
2022 
2023       OS << ']';
2024 
2025       // Compute the index of the next operand descriptor.
2026       AsmDescOp += 1 + InlineAsm::getNumOperandRegisters(Flag);
2027     } else
2028       MO.print(OS, MST, TRI);
2029   }
2030 
2031   bool HaveSemi = false;
2032   const unsigned PrintableFlags = FrameSetup | FrameDestroy;
2033   if (Flags & PrintableFlags) {
2034     if (!HaveSemi) {
2035       OS << ";";
2036       HaveSemi = true;
2037     }
2038     OS << " flags: ";
2039 
2040     if (Flags & FrameSetup)
2041       OS << "FrameSetup";
2042 
2043     if (Flags & FrameDestroy)
2044       OS << "FrameDestroy";
2045   }
2046 
2047   if (!memoperands_empty()) {
2048     if (!HaveSemi) {
2049       OS << ";";
2050       HaveSemi = true;
2051     }
2052 
2053     OS << " mem:";
2054     for (mmo_iterator i = memoperands_begin(), e = memoperands_end();
2055          i != e; ++i) {
2056       (*i)->print(OS, MST);
2057       if (std::next(i) != e)
2058         OS << " ";
2059     }
2060   }
2061 
2062   // Print the regclass of any virtual registers encountered.
2063   if (MRI && !VirtRegs.empty()) {
2064     if (!HaveSemi) {
2065       OS << ";";
2066       HaveSemi = true;
2067     }
2068     for (unsigned i = 0; i != VirtRegs.size(); ++i) {
2069       const RegClassOrRegBank &RC = MRI->getRegClassOrRegBank(VirtRegs[i]);
2070       if (!RC)
2071         continue;
2072       // Generic virtual registers do not have register classes.
2073       if (RC.is<const RegisterBank *>())
2074         OS << " " << RC.get<const RegisterBank *>()->getName();
2075       else
2076         OS << " "
2077            << TRI->getRegClassName(RC.get<const TargetRegisterClass *>());
2078       OS << ':' << PrintReg(VirtRegs[i]);
2079       for (unsigned j = i+1; j != VirtRegs.size();) {
2080         if (MRI->getRegClassOrRegBank(VirtRegs[j]) != RC) {
2081           ++j;
2082           continue;
2083         }
2084         if (VirtRegs[i] != VirtRegs[j])
2085           OS << "," << PrintReg(VirtRegs[j]);
2086         VirtRegs.erase(VirtRegs.begin()+j);
2087       }
2088     }
2089   }
2090 
2091   // Print debug location information.
2092   if (isDebugValue() && getOperand(e - 2).isMetadata()) {
2093     if (!HaveSemi)
2094       OS << ";";
2095     auto *DV = cast<DILocalVariable>(getOperand(e - 2).getMetadata());
2096     OS << " line no:" <<  DV->getLine();
2097     if (auto *InlinedAt = debugLoc->getInlinedAt()) {
2098       DebugLoc InlinedAtDL(InlinedAt);
2099       if (InlinedAtDL && MF) {
2100         OS << " inlined @[ ";
2101         InlinedAtDL.print(OS);
2102         OS << " ]";
2103       }
2104     }
2105     if (isIndirectDebugValue())
2106       OS << " indirect";
2107   } else if (SkipDebugLoc) {
2108     return;
2109   } else if (debugLoc && MF) {
2110     if (!HaveSemi)
2111       OS << ";";
2112     OS << " dbg:";
2113     debugLoc.print(OS);
2114   }
2115 
2116   OS << '\n';
2117 }
2118 
2119 bool MachineInstr::addRegisterKilled(unsigned IncomingReg,
2120                                      const TargetRegisterInfo *RegInfo,
2121                                      bool AddIfNotFound) {
2122   bool isPhysReg = TargetRegisterInfo::isPhysicalRegister(IncomingReg);
2123   bool hasAliases = isPhysReg &&
2124     MCRegAliasIterator(IncomingReg, RegInfo, false).isValid();
2125   bool Found = false;
2126   SmallVector<unsigned,4> DeadOps;
2127   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
2128     MachineOperand &MO = getOperand(i);
2129     if (!MO.isReg() || !MO.isUse() || MO.isUndef())
2130       continue;
2131 
2132     // DEBUG_VALUE nodes do not contribute to code generation and should
2133     // always be ignored. Failure to do so may result in trying to modify
2134     // KILL flags on DEBUG_VALUE nodes.
2135     if (MO.isDebug())
2136       continue;
2137 
2138     unsigned Reg = MO.getReg();
2139     if (!Reg)
2140       continue;
2141 
2142     if (Reg == IncomingReg) {
2143       if (!Found) {
2144         if (MO.isKill())
2145           // The register is already marked kill.
2146           return true;
2147         if (isPhysReg && isRegTiedToDefOperand(i))
2148           // Two-address uses of physregs must not be marked kill.
2149           return true;
2150         MO.setIsKill();
2151         Found = true;
2152       }
2153     } else if (hasAliases && MO.isKill() &&
2154                TargetRegisterInfo::isPhysicalRegister(Reg)) {
2155       // A super-register kill already exists.
2156       if (RegInfo->isSuperRegister(IncomingReg, Reg))
2157         return true;
2158       if (RegInfo->isSubRegister(IncomingReg, Reg))
2159         DeadOps.push_back(i);
2160     }
2161   }
2162 
2163   // Trim unneeded kill operands.
2164   while (!DeadOps.empty()) {
2165     unsigned OpIdx = DeadOps.back();
2166     if (getOperand(OpIdx).isImplicit())
2167       RemoveOperand(OpIdx);
2168     else
2169       getOperand(OpIdx).setIsKill(false);
2170     DeadOps.pop_back();
2171   }
2172 
2173   // If not found, this means an alias of one of the operands is killed. Add a
2174   // new implicit operand if required.
2175   if (!Found && AddIfNotFound) {
2176     addOperand(MachineOperand::CreateReg(IncomingReg,
2177                                          false /*IsDef*/,
2178                                          true  /*IsImp*/,
2179                                          true  /*IsKill*/));
2180     return true;
2181   }
2182   return Found;
2183 }
2184 
2185 void MachineInstr::clearRegisterKills(unsigned Reg,
2186                                       const TargetRegisterInfo *RegInfo) {
2187   if (!TargetRegisterInfo::isPhysicalRegister(Reg))
2188     RegInfo = nullptr;
2189   for (MachineOperand &MO : operands()) {
2190     if (!MO.isReg() || !MO.isUse() || !MO.isKill())
2191       continue;
2192     unsigned OpReg = MO.getReg();
2193     if ((RegInfo && RegInfo->regsOverlap(Reg, OpReg)) || Reg == OpReg)
2194       MO.setIsKill(false);
2195   }
2196 }
2197 
2198 bool MachineInstr::addRegisterDead(unsigned Reg,
2199                                    const TargetRegisterInfo *RegInfo,
2200                                    bool AddIfNotFound) {
2201   bool isPhysReg = TargetRegisterInfo::isPhysicalRegister(Reg);
2202   bool hasAliases = isPhysReg &&
2203     MCRegAliasIterator(Reg, RegInfo, false).isValid();
2204   bool Found = false;
2205   SmallVector<unsigned,4> DeadOps;
2206   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
2207     MachineOperand &MO = getOperand(i);
2208     if (!MO.isReg() || !MO.isDef())
2209       continue;
2210     unsigned MOReg = MO.getReg();
2211     if (!MOReg)
2212       continue;
2213 
2214     if (MOReg == Reg) {
2215       MO.setIsDead();
2216       Found = true;
2217     } else if (hasAliases && MO.isDead() &&
2218                TargetRegisterInfo::isPhysicalRegister(MOReg)) {
2219       // There exists a super-register that's marked dead.
2220       if (RegInfo->isSuperRegister(Reg, MOReg))
2221         return true;
2222       if (RegInfo->isSubRegister(Reg, MOReg))
2223         DeadOps.push_back(i);
2224     }
2225   }
2226 
2227   // Trim unneeded dead operands.
2228   while (!DeadOps.empty()) {
2229     unsigned OpIdx = DeadOps.back();
2230     if (getOperand(OpIdx).isImplicit())
2231       RemoveOperand(OpIdx);
2232     else
2233       getOperand(OpIdx).setIsDead(false);
2234     DeadOps.pop_back();
2235   }
2236 
2237   // If not found, this means an alias of one of the operands is dead. Add a
2238   // new implicit operand if required.
2239   if (Found || !AddIfNotFound)
2240     return Found;
2241 
2242   addOperand(MachineOperand::CreateReg(Reg,
2243                                        true  /*IsDef*/,
2244                                        true  /*IsImp*/,
2245                                        false /*IsKill*/,
2246                                        true  /*IsDead*/));
2247   return true;
2248 }
2249 
2250 void MachineInstr::clearRegisterDeads(unsigned Reg) {
2251   for (MachineOperand &MO : operands()) {
2252     if (!MO.isReg() || !MO.isDef() || MO.getReg() != Reg)
2253       continue;
2254     MO.setIsDead(false);
2255   }
2256 }
2257 
2258 void MachineInstr::setRegisterDefReadUndef(unsigned Reg, bool IsUndef) {
2259   for (MachineOperand &MO : operands()) {
2260     if (!MO.isReg() || !MO.isDef() || MO.getReg() != Reg || MO.getSubReg() == 0)
2261       continue;
2262     MO.setIsUndef(IsUndef);
2263   }
2264 }
2265 
2266 void MachineInstr::addRegisterDefined(unsigned Reg,
2267                                       const TargetRegisterInfo *RegInfo) {
2268   if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
2269     MachineOperand *MO = findRegisterDefOperand(Reg, false, RegInfo);
2270     if (MO)
2271       return;
2272   } else {
2273     for (const MachineOperand &MO : operands()) {
2274       if (MO.isReg() && MO.getReg() == Reg && MO.isDef() &&
2275           MO.getSubReg() == 0)
2276         return;
2277     }
2278   }
2279   addOperand(MachineOperand::CreateReg(Reg,
2280                                        true  /*IsDef*/,
2281                                        true  /*IsImp*/));
2282 }
2283 
2284 void MachineInstr::setPhysRegsDeadExcept(ArrayRef<unsigned> UsedRegs,
2285                                          const TargetRegisterInfo &TRI) {
2286   bool HasRegMask = false;
2287   for (MachineOperand &MO : operands()) {
2288     if (MO.isRegMask()) {
2289       HasRegMask = true;
2290       continue;
2291     }
2292     if (!MO.isReg() || !MO.isDef()) continue;
2293     unsigned Reg = MO.getReg();
2294     if (!TargetRegisterInfo::isPhysicalRegister(Reg)) continue;
2295     // If there are no uses, including partial uses, the def is dead.
2296     if (llvm::none_of(UsedRegs,
2297                       [&](unsigned Use) { return TRI.regsOverlap(Use, Reg); }))
2298       MO.setIsDead();
2299   }
2300 
2301   // This is a call with a register mask operand.
2302   // Mask clobbers are always dead, so add defs for the non-dead defines.
2303   if (HasRegMask)
2304     for (ArrayRef<unsigned>::iterator I = UsedRegs.begin(), E = UsedRegs.end();
2305          I != E; ++I)
2306       addRegisterDefined(*I, &TRI);
2307 }
2308 
2309 unsigned
2310 MachineInstrExpressionTrait::getHashValue(const MachineInstr* const &MI) {
2311   // Build up a buffer of hash code components.
2312   SmallVector<size_t, 8> HashComponents;
2313   HashComponents.reserve(MI->getNumOperands() + 1);
2314   HashComponents.push_back(MI->getOpcode());
2315   for (const MachineOperand &MO : MI->operands()) {
2316     if (MO.isReg() && MO.isDef() &&
2317         TargetRegisterInfo::isVirtualRegister(MO.getReg()))
2318       continue;  // Skip virtual register defs.
2319 
2320     HashComponents.push_back(hash_value(MO));
2321   }
2322   return hash_combine_range(HashComponents.begin(), HashComponents.end());
2323 }
2324 
2325 void MachineInstr::emitError(StringRef Msg) const {
2326   // Find the source location cookie.
2327   unsigned LocCookie = 0;
2328   const MDNode *LocMD = nullptr;
2329   for (unsigned i = getNumOperands(); i != 0; --i) {
2330     if (getOperand(i-1).isMetadata() &&
2331         (LocMD = getOperand(i-1).getMetadata()) &&
2332         LocMD->getNumOperands() != 0) {
2333       if (const ConstantInt *CI =
2334               mdconst::dyn_extract<ConstantInt>(LocMD->getOperand(0))) {
2335         LocCookie = CI->getZExtValue();
2336         break;
2337       }
2338     }
2339   }
2340 
2341   if (const MachineBasicBlock *MBB = getParent())
2342     if (const MachineFunction *MF = MBB->getParent())
2343       return MF->getMMI().getModule()->getContext().emitError(LocCookie, Msg);
2344   report_fatal_error(Msg);
2345 }
2346 
2347 MachineInstrBuilder llvm::BuildMI(MachineFunction &MF, const DebugLoc &DL,
2348                                   const MCInstrDesc &MCID, bool IsIndirect,
2349                                   unsigned Reg, unsigned Offset,
2350                                   const MDNode *Variable, const MDNode *Expr) {
2351   assert(isa<DILocalVariable>(Variable) && "not a variable");
2352   assert(cast<DIExpression>(Expr)->isValid() && "not an expression");
2353   assert(cast<DILocalVariable>(Variable)->isValidLocationForIntrinsic(DL) &&
2354          "Expected inlined-at fields to agree");
2355   if (IsIndirect)
2356     return BuildMI(MF, DL, MCID)
2357         .addReg(Reg, RegState::Debug)
2358         .addImm(Offset)
2359         .addMetadata(Variable)
2360         .addMetadata(Expr);
2361   else {
2362     assert(Offset == 0 && "A direct address cannot have an offset.");
2363     return BuildMI(MF, DL, MCID)
2364         .addReg(Reg, RegState::Debug)
2365         .addReg(0U, RegState::Debug)
2366         .addMetadata(Variable)
2367         .addMetadata(Expr);
2368   }
2369 }
2370 
2371 MachineInstrBuilder llvm::BuildMI(MachineBasicBlock &BB,
2372                                   MachineBasicBlock::iterator I,
2373                                   const DebugLoc &DL, const MCInstrDesc &MCID,
2374                                   bool IsIndirect, unsigned Reg,
2375                                   unsigned Offset, const MDNode *Variable,
2376                                   const MDNode *Expr) {
2377   assert(isa<DILocalVariable>(Variable) && "not a variable");
2378   assert(cast<DIExpression>(Expr)->isValid() && "not an expression");
2379   MachineFunction &MF = *BB.getParent();
2380   MachineInstr *MI =
2381       BuildMI(MF, DL, MCID, IsIndirect, Reg, Offset, Variable, Expr);
2382   BB.insert(I, MI);
2383   return MachineInstrBuilder(MF, MI);
2384 }
2385 
2386 MachineInstr *llvm::buildDbgValueForSpill(MachineBasicBlock &BB,
2387                                           MachineBasicBlock::iterator I,
2388                                           const MachineInstr &Orig,
2389                                           int FrameIndex) {
2390   const MDNode *Var = Orig.getDebugVariable();
2391   const auto *Expr = cast_or_null<DIExpression>(Orig.getDebugExpression());
2392   bool IsIndirect = Orig.isIndirectDebugValue();
2393   uint64_t Offset = IsIndirect ? Orig.getOperand(1).getImm() : 0;
2394   DebugLoc DL = Orig.getDebugLoc();
2395   assert(cast<DILocalVariable>(Var)->isValidLocationForIntrinsic(DL) &&
2396          "Expected inlined-at fields to agree");
2397   // If the DBG_VALUE already was a memory location, add an extra
2398   // DW_OP_deref. Otherwise just turning this from a register into a
2399   // memory/indirect location is sufficient.
2400   if (IsIndirect)
2401     Expr = DIExpression::prepend(Expr, DIExpression::WithDeref);
2402   return BuildMI(BB, I, DL, Orig.getDesc())
2403       .addFrameIndex(FrameIndex)
2404       .addImm(Offset)
2405       .addMetadata(Var)
2406       .addMetadata(Expr);
2407 }
2408