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<int> PrintRegMaskNumRegs(
77     "print-regmask-num-regs",
78     cl::desc("Number of registers to limit to when "
79              "printing regmask operands in IR dumps. "
80              "unlimited = -1"),
81     cl::init(32), cl::Hidden);
82 
83 //===----------------------------------------------------------------------===//
84 // MachineOperand Implementation
85 //===----------------------------------------------------------------------===//
86 
87 void MachineOperand::setReg(unsigned Reg) {
88   if (getReg() == Reg) return; // No change.
89 
90   // Otherwise, we have to change the register.  If this operand is embedded
91   // into a machine function, we need to update the old and new register's
92   // use/def lists.
93   if (MachineInstr *MI = getParent())
94     if (MachineBasicBlock *MBB = MI->getParent())
95       if (MachineFunction *MF = MBB->getParent()) {
96         MachineRegisterInfo &MRI = MF->getRegInfo();
97         MRI.removeRegOperandFromUseList(this);
98         SmallContents.RegNo = Reg;
99         MRI.addRegOperandToUseList(this);
100         return;
101       }
102 
103   // Otherwise, just change the register, no problem.  :)
104   SmallContents.RegNo = Reg;
105 }
106 
107 void MachineOperand::substVirtReg(unsigned Reg, unsigned SubIdx,
108                                   const TargetRegisterInfo &TRI) {
109   assert(TargetRegisterInfo::isVirtualRegister(Reg));
110   if (SubIdx && getSubReg())
111     SubIdx = TRI.composeSubRegIndices(SubIdx, getSubReg());
112   setReg(Reg);
113   if (SubIdx)
114     setSubReg(SubIdx);
115 }
116 
117 void MachineOperand::substPhysReg(unsigned Reg, const TargetRegisterInfo &TRI) {
118   assert(TargetRegisterInfo::isPhysicalRegister(Reg));
119   if (getSubReg()) {
120     Reg = TRI.getSubReg(Reg, getSubReg());
121     // Note that getSubReg() may return 0 if the sub-register doesn't exist.
122     // That won't happen in legal code.
123     setSubReg(0);
124     if (isDef())
125       setIsUndef(false);
126   }
127   setReg(Reg);
128 }
129 
130 /// Change a def to a use, or a use to a def.
131 void MachineOperand::setIsDef(bool Val) {
132   assert(isReg() && "Wrong MachineOperand accessor");
133   assert((!Val || !isDebug()) && "Marking a debug operation as def");
134   if (IsDef == Val)
135     return;
136   // MRI may keep uses and defs in different list positions.
137   if (MachineInstr *MI = getParent())
138     if (MachineBasicBlock *MBB = MI->getParent())
139       if (MachineFunction *MF = MBB->getParent()) {
140         MachineRegisterInfo &MRI = MF->getRegInfo();
141         MRI.removeRegOperandFromUseList(this);
142         IsDef = Val;
143         MRI.addRegOperandToUseList(this);
144         return;
145       }
146   IsDef = Val;
147 }
148 
149 // If this operand is currently a register operand, and if this is in a
150 // function, deregister the operand from the register's use/def list.
151 void MachineOperand::removeRegFromUses() {
152   if (!isReg() || !isOnRegUseList())
153     return;
154 
155   if (MachineInstr *MI = getParent()) {
156     if (MachineBasicBlock *MBB = MI->getParent()) {
157       if (MachineFunction *MF = MBB->getParent())
158         MF->getRegInfo().removeRegOperandFromUseList(this);
159     }
160   }
161 }
162 
163 /// ChangeToImmediate - Replace this operand with a new immediate operand of
164 /// the specified value.  If an operand is known to be an immediate already,
165 /// the setImm method should be used.
166 void MachineOperand::ChangeToImmediate(int64_t ImmVal) {
167   assert((!isReg() || !isTied()) && "Cannot change a tied operand into an imm");
168 
169   removeRegFromUses();
170 
171   OpKind = MO_Immediate;
172   Contents.ImmVal = ImmVal;
173 }
174 
175 void MachineOperand::ChangeToFPImmediate(const ConstantFP *FPImm) {
176   assert((!isReg() || !isTied()) && "Cannot change a tied operand into an imm");
177 
178   removeRegFromUses();
179 
180   OpKind = MO_FPImmediate;
181   Contents.CFP = FPImm;
182 }
183 
184 void MachineOperand::ChangeToES(const char *SymName, unsigned char TargetFlags) {
185   assert((!isReg() || !isTied()) &&
186          "Cannot change a tied operand into an external symbol");
187 
188   removeRegFromUses();
189 
190   OpKind = MO_ExternalSymbol;
191   Contents.OffsetedInfo.Val.SymbolName = SymName;
192   setOffset(0); // Offset is always 0.
193   setTargetFlags(TargetFlags);
194 }
195 
196 void MachineOperand::ChangeToMCSymbol(MCSymbol *Sym) {
197   assert((!isReg() || !isTied()) &&
198          "Cannot change a tied operand into an MCSymbol");
199 
200   removeRegFromUses();
201 
202   OpKind = MO_MCSymbol;
203   Contents.Sym = Sym;
204 }
205 
206 void MachineOperand::ChangeToFrameIndex(int Idx) {
207   assert((!isReg() || !isTied()) &&
208          "Cannot change a tied operand into a FrameIndex");
209 
210   removeRegFromUses();
211 
212   OpKind = MO_FrameIndex;
213   setIndex(Idx);
214 }
215 
216 void MachineOperand::ChangeToTargetIndex(unsigned Idx, int64_t Offset,
217                                          unsigned char TargetFlags) {
218   assert((!isReg() || !isTied()) &&
219          "Cannot change a tied operand into a FrameIndex");
220 
221   removeRegFromUses();
222 
223   OpKind = MO_TargetIndex;
224   setIndex(Idx);
225   setOffset(Offset);
226   setTargetFlags(TargetFlags);
227 }
228 
229 /// ChangeToRegister - Replace this operand with a new register operand of
230 /// the specified value.  If an operand is known to be an register already,
231 /// the setReg method should be used.
232 void MachineOperand::ChangeToRegister(unsigned Reg, bool isDef, bool isImp,
233                                       bool isKill, bool isDead, bool isUndef,
234                                       bool isDebug) {
235   MachineRegisterInfo *RegInfo = nullptr;
236   if (MachineInstr *MI = getParent())
237     if (MachineBasicBlock *MBB = MI->getParent())
238       if (MachineFunction *MF = MBB->getParent())
239         RegInfo = &MF->getRegInfo();
240   // If this operand is already a register operand, remove it from the
241   // register's use/def lists.
242   bool WasReg = isReg();
243   if (RegInfo && WasReg)
244     RegInfo->removeRegOperandFromUseList(this);
245 
246   // Change this to a register and set the reg#.
247   OpKind = MO_Register;
248   SmallContents.RegNo = Reg;
249   SubReg_TargetFlags = 0;
250   IsDef = isDef;
251   IsImp = isImp;
252   IsKill = isKill;
253   IsDead = isDead;
254   IsUndef = isUndef;
255   IsInternalRead = false;
256   IsEarlyClobber = false;
257   IsDebug = isDebug;
258   // Ensure isOnRegUseList() returns false.
259   Contents.Reg.Prev = nullptr;
260   // Preserve the tie when the operand was already a register.
261   if (!WasReg)
262     TiedTo = 0;
263 
264   // If this operand is embedded in a function, add the operand to the
265   // register's use/def list.
266   if (RegInfo)
267     RegInfo->addRegOperandToUseList(this);
268 }
269 
270 /// isIdenticalTo - Return true if this operand is identical to the specified
271 /// operand. Note that this should stay in sync with the hash_value overload
272 /// below.
273 bool MachineOperand::isIdenticalTo(const MachineOperand &Other) const {
274   if (getType() != Other.getType() ||
275       getTargetFlags() != Other.getTargetFlags())
276     return false;
277 
278   switch (getType()) {
279   case MachineOperand::MO_Register:
280     return getReg() == Other.getReg() && isDef() == Other.isDef() &&
281            getSubReg() == Other.getSubReg();
282   case MachineOperand::MO_Immediate:
283     return getImm() == Other.getImm();
284   case MachineOperand::MO_CImmediate:
285     return getCImm() == Other.getCImm();
286   case MachineOperand::MO_FPImmediate:
287     return getFPImm() == Other.getFPImm();
288   case MachineOperand::MO_MachineBasicBlock:
289     return getMBB() == Other.getMBB();
290   case MachineOperand::MO_FrameIndex:
291     return getIndex() == Other.getIndex();
292   case MachineOperand::MO_ConstantPoolIndex:
293   case MachineOperand::MO_TargetIndex:
294     return getIndex() == Other.getIndex() && getOffset() == Other.getOffset();
295   case MachineOperand::MO_JumpTableIndex:
296     return getIndex() == Other.getIndex();
297   case MachineOperand::MO_GlobalAddress:
298     return getGlobal() == Other.getGlobal() && getOffset() == Other.getOffset();
299   case MachineOperand::MO_ExternalSymbol:
300     return strcmp(getSymbolName(), Other.getSymbolName()) == 0 &&
301            getOffset() == Other.getOffset();
302   case MachineOperand::MO_BlockAddress:
303     return getBlockAddress() == Other.getBlockAddress() &&
304            getOffset() == Other.getOffset();
305   case MachineOperand::MO_RegisterMask:
306   case MachineOperand::MO_RegisterLiveOut: {
307     // Shallow compare of the two RegMasks
308     const uint32_t *RegMask = getRegMask();
309     const uint32_t *OtherRegMask = Other.getRegMask();
310     if (RegMask == OtherRegMask)
311       return true;
312 
313     // Calculate the size of the RegMask
314     const MachineFunction *MF = getParent()->getMF();
315     const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo();
316     unsigned RegMaskSize = (TRI->getNumRegs() + 31) / 32;
317 
318     // Deep compare of the two RegMasks
319     return std::equal(RegMask, RegMask + RegMaskSize, OtherRegMask);
320   }
321   case MachineOperand::MO_MCSymbol:
322     return getMCSymbol() == Other.getMCSymbol();
323   case MachineOperand::MO_CFIIndex: {
324     const MachineFunction *MF = getParent()->getParent()->getParent();
325     const MachineFunction *OtherMF =
326         Other.getParent()->getParent()->getParent();
327     MCCFIInstruction Inst = MF->getFrameInstructions()[getCFIIndex()];
328     MCCFIInstruction OtherInst =
329         OtherMF->getFrameInstructions()[Other.getCFIIndex()];
330     MCCFIInstruction::OpType op = Inst.getOperation();
331     if (op != OtherInst.getOperation()) return false;
332     switch (op) {
333     case MCCFIInstruction::OpDefCfa:
334     case MCCFIInstruction::OpOffset:
335     case MCCFIInstruction::OpRelOffset:
336       if (Inst.getRegister() != OtherInst.getRegister()) return false;
337       if (Inst.getOffset() != OtherInst.getOffset()) return false;
338       break;
339     case MCCFIInstruction::OpRestore:
340     case MCCFIInstruction::OpUndefined:
341     case MCCFIInstruction::OpSameValue:
342     case MCCFIInstruction::OpDefCfaRegister:
343       if (Inst.getRegister() != OtherInst.getRegister()) return false;
344       break;
345     case MCCFIInstruction::OpRegister:
346       if (Inst.getRegister() != OtherInst.getRegister()) return false;
347       if (Inst.getRegister2() != OtherInst.getRegister2()) return false;
348       break;
349     case MCCFIInstruction::OpDefCfaOffset:
350     case MCCFIInstruction::OpAdjustCfaOffset:
351     case MCCFIInstruction::OpGnuArgsSize:
352       if (Inst.getOffset() != OtherInst.getOffset()) return false;
353       break;
354     case MCCFIInstruction::OpRememberState:
355     case MCCFIInstruction::OpRestoreState:
356     case MCCFIInstruction::OpEscape:
357     case MCCFIInstruction::OpWindowSave:
358       break;
359     }
360     return true;
361   }
362   case MachineOperand::MO_Metadata:
363     return getMetadata() == Other.getMetadata();
364   case MachineOperand::MO_IntrinsicID:
365     return getIntrinsicID() == Other.getIntrinsicID();
366   case MachineOperand::MO_Predicate:
367     return getPredicate() == Other.getPredicate();
368   }
369   llvm_unreachable("Invalid machine operand type");
370 }
371 
372 // Note: this must stay exactly in sync with isIdenticalTo above.
373 hash_code llvm::hash_value(const MachineOperand &MO) {
374   switch (MO.getType()) {
375   case MachineOperand::MO_Register:
376     // Register operands don't have target flags.
377     return hash_combine(MO.getType(), MO.getReg(), MO.getSubReg(), MO.isDef());
378   case MachineOperand::MO_Immediate:
379     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getImm());
380   case MachineOperand::MO_CImmediate:
381     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getCImm());
382   case MachineOperand::MO_FPImmediate:
383     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getFPImm());
384   case MachineOperand::MO_MachineBasicBlock:
385     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getMBB());
386   case MachineOperand::MO_FrameIndex:
387     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIndex());
388   case MachineOperand::MO_ConstantPoolIndex:
389   case MachineOperand::MO_TargetIndex:
390     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIndex(),
391                         MO.getOffset());
392   case MachineOperand::MO_JumpTableIndex:
393     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIndex());
394   case MachineOperand::MO_ExternalSymbol:
395     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getOffset(),
396                         MO.getSymbolName());
397   case MachineOperand::MO_GlobalAddress:
398     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getGlobal(),
399                         MO.getOffset());
400   case MachineOperand::MO_BlockAddress:
401     return hash_combine(MO.getType(), MO.getTargetFlags(),
402                         MO.getBlockAddress(), MO.getOffset());
403   case MachineOperand::MO_RegisterMask:
404   case MachineOperand::MO_RegisterLiveOut:
405     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getRegMask());
406   case MachineOperand::MO_Metadata:
407     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getMetadata());
408   case MachineOperand::MO_MCSymbol:
409     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getMCSymbol());
410   case MachineOperand::MO_CFIIndex: {
411     const MachineFunction *MF = MO.getParent()->getParent()->getParent();
412     MCCFIInstruction Inst = MF->getFrameInstructions()[MO.getCFIIndex()];
413     return hash_combine(MO.getType(), MO.getTargetFlags(), Inst.getOperation(),
414                         Inst.getRegister(), Inst.getRegister2(),
415                         Inst.getOffset());
416   }
417   case MachineOperand::MO_IntrinsicID:
418     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getIntrinsicID());
419   case MachineOperand::MO_Predicate:
420     return hash_combine(MO.getType(), MO.getTargetFlags(), MO.getPredicate());
421   }
422   llvm_unreachable("Invalid machine operand type");
423 }
424 
425 void MachineOperand::print(raw_ostream &OS, const TargetRegisterInfo *TRI,
426                            const TargetIntrinsicInfo *IntrinsicInfo) const {
427   ModuleSlotTracker DummyMST(nullptr);
428   print(OS, DummyMST, TRI, IntrinsicInfo);
429 }
430 
431 void MachineOperand::print(raw_ostream &OS, ModuleSlotTracker &MST,
432                            const TargetRegisterInfo *TRI,
433                            const TargetIntrinsicInfo *IntrinsicInfo) const {
434   switch (getType()) {
435   case MachineOperand::MO_Register:
436     OS << PrintReg(getReg(), TRI, getSubReg());
437 
438     if (isDef() || isKill() || isDead() || isImplicit() || isUndef() ||
439         isInternalRead() || isEarlyClobber() || isTied()) {
440       OS << '<';
441       bool NeedComma = false;
442       if (isDef()) {
443         if (NeedComma) OS << ',';
444         if (isEarlyClobber())
445           OS << "earlyclobber,";
446         if (isImplicit())
447           OS << "imp-";
448         OS << "def";
449         NeedComma = true;
450         // <def,read-undef> only makes sense when getSubReg() is set.
451         // Don't clutter the output otherwise.
452         if (isUndef() && getSubReg())
453           OS << ",read-undef";
454       } else if (isImplicit()) {
455         OS << "imp-use";
456         NeedComma = true;
457       }
458 
459       if (isKill()) {
460         if (NeedComma) OS << ',';
461         OS << "kill";
462         NeedComma = true;
463       }
464       if (isDead()) {
465         if (NeedComma) OS << ',';
466         OS << "dead";
467         NeedComma = true;
468       }
469       if (isUndef() && isUse()) {
470         if (NeedComma) OS << ',';
471         OS << "undef";
472         NeedComma = true;
473       }
474       if (isInternalRead()) {
475         if (NeedComma) OS << ',';
476         OS << "internal";
477         NeedComma = true;
478       }
479       if (isTied()) {
480         if (NeedComma) OS << ',';
481         OS << "tied";
482         if (TiedTo != 15)
483           OS << unsigned(TiedTo - 1);
484       }
485       OS << '>';
486     }
487     break;
488   case MachineOperand::MO_Immediate:
489     OS << getImm();
490     break;
491   case MachineOperand::MO_CImmediate:
492     getCImm()->getValue().print(OS, false);
493     break;
494   case MachineOperand::MO_FPImmediate:
495     if (getFPImm()->getType()->isFloatTy()) {
496       OS << getFPImm()->getValueAPF().convertToFloat();
497     } else if (getFPImm()->getType()->isHalfTy()) {
498       APFloat APF = getFPImm()->getValueAPF();
499       bool Unused;
500       APF.convert(APFloat::IEEEsingle(), APFloat::rmNearestTiesToEven, &Unused);
501       OS << "half " << APF.convertToFloat();
502     } else if (getFPImm()->getType()->isFP128Ty()) {
503       APFloat APF = getFPImm()->getValueAPF();
504       SmallString<16> Str;
505       getFPImm()->getValueAPF().toString(Str);
506       OS << "quad " << Str;
507     } else if (getFPImm()->getType()->isX86_FP80Ty()) {
508       APFloat APF = getFPImm()->getValueAPF();
509       OS << "x86_fp80 0xK";
510       APInt API = APF.bitcastToAPInt();
511       OS << format_hex_no_prefix(API.getHiBits(16).getZExtValue(), 4,
512                                  /*Upper=*/true);
513       OS << format_hex_no_prefix(API.getLoBits(64).getZExtValue(), 16,
514                                  /*Upper=*/true);
515     } else {
516       OS << getFPImm()->getValueAPF().convertToDouble();
517     }
518     break;
519   case MachineOperand::MO_MachineBasicBlock:
520     OS << "<BB#" << getMBB()->getNumber() << ">";
521     break;
522   case MachineOperand::MO_FrameIndex:
523     OS << "<fi#" << getIndex() << '>';
524     break;
525   case MachineOperand::MO_ConstantPoolIndex:
526     OS << "<cp#" << getIndex();
527     if (getOffset()) OS << "+" << getOffset();
528     OS << '>';
529     break;
530   case MachineOperand::MO_TargetIndex:
531     OS << "<ti#" << getIndex();
532     if (getOffset()) OS << "+" << getOffset();
533     OS << '>';
534     break;
535   case MachineOperand::MO_JumpTableIndex:
536     OS << "<jt#" << getIndex() << '>';
537     break;
538   case MachineOperand::MO_GlobalAddress:
539     OS << "<ga:";
540     getGlobal()->printAsOperand(OS, /*PrintType=*/false, MST);
541     if (getOffset()) OS << "+" << getOffset();
542     OS << '>';
543     break;
544   case MachineOperand::MO_ExternalSymbol:
545     OS << "<es:" << getSymbolName();
546     if (getOffset()) OS << "+" << getOffset();
547     OS << '>';
548     break;
549   case MachineOperand::MO_BlockAddress:
550     OS << '<';
551     getBlockAddress()->printAsOperand(OS, /*PrintType=*/false, MST);
552     if (getOffset()) OS << "+" << getOffset();
553     OS << '>';
554     break;
555   case MachineOperand::MO_RegisterMask: {
556     unsigned NumRegsInMask = 0;
557     unsigned NumRegsEmitted = 0;
558     OS << "<regmask";
559     for (unsigned i = 0; i < TRI->getNumRegs(); ++i) {
560       unsigned MaskWord = i / 32;
561       unsigned MaskBit = i % 32;
562       if (getRegMask()[MaskWord] & (1 << MaskBit)) {
563         if (PrintRegMaskNumRegs < 0 ||
564             NumRegsEmitted <= static_cast<unsigned>(PrintRegMaskNumRegs)) {
565           OS << " " << PrintReg(i, TRI);
566           NumRegsEmitted++;
567         }
568         NumRegsInMask++;
569       }
570     }
571     if (NumRegsEmitted != NumRegsInMask)
572       OS << " and " << (NumRegsInMask - NumRegsEmitted) << " more...";
573     OS << ">";
574     break;
575   }
576   case MachineOperand::MO_RegisterLiveOut:
577     OS << "<regliveout>";
578     break;
579   case MachineOperand::MO_Metadata:
580     OS << '<';
581     getMetadata()->printAsOperand(OS, MST);
582     OS << '>';
583     break;
584   case MachineOperand::MO_MCSymbol:
585     OS << "<MCSym=" << *getMCSymbol() << '>';
586     break;
587   case MachineOperand::MO_CFIIndex:
588     OS << "<call frame instruction>";
589     break;
590   case MachineOperand::MO_IntrinsicID: {
591     Intrinsic::ID ID = getIntrinsicID();
592     if (ID < Intrinsic::num_intrinsics)
593       OS << "<intrinsic:@" << Intrinsic::getName(ID, None) << '>';
594     else if (IntrinsicInfo)
595       OS << "<intrinsic:@" << IntrinsicInfo->getName(ID) << '>';
596     else
597       OS << "<intrinsic:" << ID << '>';
598     break;
599   }
600   case MachineOperand::MO_Predicate: {
601     auto Pred = static_cast<CmpInst::Predicate>(getPredicate());
602     OS << '<' << (CmpInst::isIntPredicate(Pred) ? "intpred" : "floatpred")
603        << CmpInst::getPredicateName(Pred) << '>';
604     break;
605   }
606   }
607   if (unsigned TF = getTargetFlags())
608     OS << "[TF=" << TF << ']';
609 }
610 
611 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
612 LLVM_DUMP_METHOD void MachineOperand::dump() const {
613   dbgs() << *this << '\n';
614 }
615 #endif
616 
617 //===----------------------------------------------------------------------===//
618 // MachineMemOperand Implementation
619 //===----------------------------------------------------------------------===//
620 
621 /// getAddrSpace - Return the LLVM IR address space number that this pointer
622 /// points into.
623 unsigned MachinePointerInfo::getAddrSpace() const {
624   if (V.isNull()) return 0;
625 
626   if (V.is<const PseudoSourceValue*>())
627     return V.get<const PseudoSourceValue*>()->getAddressSpace();
628 
629   return cast<PointerType>(V.get<const Value*>()->getType())->getAddressSpace();
630 }
631 
632 /// isDereferenceable - Return true if V is always dereferenceable for
633 /// Offset + Size byte.
634 bool MachinePointerInfo::isDereferenceable(unsigned Size, LLVMContext &C,
635                                            const DataLayout &DL) const {
636   if (!V.is<const Value*>())
637     return false;
638 
639   const Value *BasePtr = V.get<const Value*>();
640   if (BasePtr == nullptr)
641     return false;
642 
643   return isDereferenceableAndAlignedPointer(
644       BasePtr, 1, APInt(DL.getPointerSizeInBits(), Offset + Size), DL);
645 }
646 
647 /// getConstantPool - Return a MachinePointerInfo record that refers to the
648 /// constant pool.
649 MachinePointerInfo MachinePointerInfo::getConstantPool(MachineFunction &MF) {
650   return MachinePointerInfo(MF.getPSVManager().getConstantPool());
651 }
652 
653 /// getFixedStack - Return a MachinePointerInfo record that refers to the
654 /// the specified FrameIndex.
655 MachinePointerInfo MachinePointerInfo::getFixedStack(MachineFunction &MF,
656                                                      int FI, int64_t Offset) {
657   return MachinePointerInfo(MF.getPSVManager().getFixedStack(FI), Offset);
658 }
659 
660 MachinePointerInfo MachinePointerInfo::getJumpTable(MachineFunction &MF) {
661   return MachinePointerInfo(MF.getPSVManager().getJumpTable());
662 }
663 
664 MachinePointerInfo MachinePointerInfo::getGOT(MachineFunction &MF) {
665   return MachinePointerInfo(MF.getPSVManager().getGOT());
666 }
667 
668 MachinePointerInfo MachinePointerInfo::getStack(MachineFunction &MF,
669                                                 int64_t Offset,
670                                                 uint8_t ID) {
671   return MachinePointerInfo(MF.getPSVManager().getStack(), Offset,ID);
672 }
673 
674 MachineMemOperand::MachineMemOperand(MachinePointerInfo ptrinfo, Flags f,
675                                      uint64_t s, unsigned int a,
676                                      const AAMDNodes &AAInfo,
677                                      const MDNode *Ranges,
678                                      SyncScope::ID SSID,
679                                      AtomicOrdering Ordering,
680                                      AtomicOrdering FailureOrdering)
681     : PtrInfo(ptrinfo), Size(s), FlagVals(f), BaseAlignLog2(Log2_32(a) + 1),
682       AAInfo(AAInfo), Ranges(Ranges) {
683   assert((PtrInfo.V.isNull() || PtrInfo.V.is<const PseudoSourceValue*>() ||
684           isa<PointerType>(PtrInfo.V.get<const Value*>()->getType())) &&
685          "invalid pointer value");
686   assert(getBaseAlignment() == a && "Alignment is not a power of 2!");
687   assert((isLoad() || isStore()) && "Not a load/store!");
688 
689   AtomicInfo.SSID = static_cast<unsigned>(SSID);
690   assert(getSyncScopeID() == SSID && "Value truncated");
691   AtomicInfo.Ordering = static_cast<unsigned>(Ordering);
692   assert(getOrdering() == Ordering && "Value truncated");
693   AtomicInfo.FailureOrdering = static_cast<unsigned>(FailureOrdering);
694   assert(getFailureOrdering() == FailureOrdering && "Value truncated");
695 }
696 
697 /// Profile - Gather unique data for the object.
698 ///
699 void MachineMemOperand::Profile(FoldingSetNodeID &ID) const {
700   ID.AddInteger(getOffset());
701   ID.AddInteger(Size);
702   ID.AddPointer(getOpaqueValue());
703   ID.AddInteger(getFlags());
704   ID.AddInteger(getBaseAlignment());
705 }
706 
707 void MachineMemOperand::refineAlignment(const MachineMemOperand *MMO) {
708   // The Value and Offset may differ due to CSE. But the flags and size
709   // should be the same.
710   assert(MMO->getFlags() == getFlags() && "Flags mismatch!");
711   assert(MMO->getSize() == getSize() && "Size mismatch!");
712 
713   if (MMO->getBaseAlignment() >= getBaseAlignment()) {
714     // Update the alignment value.
715     BaseAlignLog2 = Log2_32(MMO->getBaseAlignment()) + 1;
716     // Also update the base and offset, because the new alignment may
717     // not be applicable with the old ones.
718     PtrInfo = MMO->PtrInfo;
719   }
720 }
721 
722 /// getAlignment - Return the minimum known alignment in bytes of the
723 /// actual memory reference.
724 uint64_t MachineMemOperand::getAlignment() const {
725   return MinAlign(getBaseAlignment(), getOffset());
726 }
727 
728 void MachineMemOperand::print(raw_ostream &OS) const {
729   ModuleSlotTracker DummyMST(nullptr);
730   print(OS, DummyMST);
731 }
732 void MachineMemOperand::print(raw_ostream &OS, ModuleSlotTracker &MST) const {
733   assert((isLoad() || isStore()) &&
734          "SV has to be a load, store or both.");
735 
736   if (isVolatile())
737     OS << "Volatile ";
738 
739   if (isLoad())
740     OS << "LD";
741   if (isStore())
742     OS << "ST";
743   OS << getSize();
744 
745   // Print the address information.
746   OS << "[";
747   if (const Value *V = getValue())
748     V->printAsOperand(OS, /*PrintType=*/false, MST);
749   else if (const PseudoSourceValue *PSV = getPseudoValue())
750     PSV->printCustom(OS);
751   else
752     OS << "<unknown>";
753 
754   unsigned AS = getAddrSpace();
755   if (AS != 0)
756     OS << "(addrspace=" << AS << ')';
757 
758   // If the alignment of the memory reference itself differs from the alignment
759   // of the base pointer, print the base alignment explicitly, next to the base
760   // pointer.
761   if (getBaseAlignment() != getAlignment())
762     OS << "(align=" << getBaseAlignment() << ")";
763 
764   if (getOffset() != 0)
765     OS << "+" << getOffset();
766   OS << "]";
767 
768   // Print the alignment of the reference.
769   if (getBaseAlignment() != getAlignment() || getBaseAlignment() != getSize())
770     OS << "(align=" << getAlignment() << ")";
771 
772   // Print TBAA info.
773   if (const MDNode *TBAAInfo = getAAInfo().TBAA) {
774     OS << "(tbaa=";
775     if (TBAAInfo->getNumOperands() > 0)
776       TBAAInfo->getOperand(0)->printAsOperand(OS, MST);
777     else
778       OS << "<unknown>";
779     OS << ")";
780   }
781 
782   // Print AA scope info.
783   if (const MDNode *ScopeInfo = getAAInfo().Scope) {
784     OS << "(alias.scope=";
785     if (ScopeInfo->getNumOperands() > 0)
786       for (unsigned i = 0, ie = ScopeInfo->getNumOperands(); i != ie; ++i) {
787         ScopeInfo->getOperand(i)->printAsOperand(OS, MST);
788         if (i != ie-1)
789           OS << ",";
790       }
791     else
792       OS << "<unknown>";
793     OS << ")";
794   }
795 
796   // Print AA noalias scope info.
797   if (const MDNode *NoAliasInfo = getAAInfo().NoAlias) {
798     OS << "(noalias=";
799     if (NoAliasInfo->getNumOperands() > 0)
800       for (unsigned i = 0, ie = NoAliasInfo->getNumOperands(); i != ie; ++i) {
801         NoAliasInfo->getOperand(i)->printAsOperand(OS, MST);
802         if (i != ie-1)
803           OS << ",";
804       }
805     else
806       OS << "<unknown>";
807     OS << ")";
808   }
809 
810   if (isNonTemporal())
811     OS << "(nontemporal)";
812   if (isDereferenceable())
813     OS << "(dereferenceable)";
814   if (isInvariant())
815     OS << "(invariant)";
816   if (getFlags() & MOTargetFlag1)
817     OS << "(flag1)";
818   if (getFlags() & MOTargetFlag2)
819     OS << "(flag2)";
820   if (getFlags() & MOTargetFlag3)
821     OS << "(flag3)";
822 }
823 
824 //===----------------------------------------------------------------------===//
825 // MachineInstr Implementation
826 //===----------------------------------------------------------------------===//
827 
828 void MachineInstr::addImplicitDefUseOperands(MachineFunction &MF) {
829   if (MCID->ImplicitDefs)
830     for (const MCPhysReg *ImpDefs = MCID->getImplicitDefs(); *ImpDefs;
831            ++ImpDefs)
832       addOperand(MF, MachineOperand::CreateReg(*ImpDefs, true, true));
833   if (MCID->ImplicitUses)
834     for (const MCPhysReg *ImpUses = MCID->getImplicitUses(); *ImpUses;
835            ++ImpUses)
836       addOperand(MF, MachineOperand::CreateReg(*ImpUses, false, true));
837 }
838 
839 /// MachineInstr ctor - This constructor creates a MachineInstr and adds the
840 /// implicit operands. It reserves space for the number of operands specified by
841 /// the MCInstrDesc.
842 MachineInstr::MachineInstr(MachineFunction &MF, const MCInstrDesc &tid,
843                            DebugLoc dl, bool NoImp)
844     : MCID(&tid), debugLoc(std::move(dl)) {
845   assert(debugLoc.hasTrivialDestructor() && "Expected trivial destructor");
846 
847   // Reserve space for the expected number of operands.
848   if (unsigned NumOps = MCID->getNumOperands() +
849     MCID->getNumImplicitDefs() + MCID->getNumImplicitUses()) {
850     CapOperands = OperandCapacity::get(NumOps);
851     Operands = MF.allocateOperandArray(CapOperands);
852   }
853 
854   if (!NoImp)
855     addImplicitDefUseOperands(MF);
856 }
857 
858 /// MachineInstr ctor - Copies MachineInstr arg exactly
859 ///
860 MachineInstr::MachineInstr(MachineFunction &MF, const MachineInstr &MI)
861     : MCID(&MI.getDesc()), NumMemRefs(MI.NumMemRefs), MemRefs(MI.MemRefs),
862       debugLoc(MI.getDebugLoc()) {
863   assert(debugLoc.hasTrivialDestructor() && "Expected trivial destructor");
864 
865   CapOperands = OperandCapacity::get(MI.getNumOperands());
866   Operands = MF.allocateOperandArray(CapOperands);
867 
868   // Copy operands.
869   for (const MachineOperand &MO : MI.operands())
870     addOperand(MF, MO);
871 
872   // Copy all the sensible flags.
873   setFlags(MI.Flags);
874 }
875 
876 /// getRegInfo - If this instruction is embedded into a MachineFunction,
877 /// return the MachineRegisterInfo object for the current function, otherwise
878 /// return null.
879 MachineRegisterInfo *MachineInstr::getRegInfo() {
880   if (MachineBasicBlock *MBB = getParent())
881     return &MBB->getParent()->getRegInfo();
882   return nullptr;
883 }
884 
885 /// RemoveRegOperandsFromUseLists - Unlink all of the register operands in
886 /// this instruction from their respective use lists.  This requires that the
887 /// operands already be on their use lists.
888 void MachineInstr::RemoveRegOperandsFromUseLists(MachineRegisterInfo &MRI) {
889   for (MachineOperand &MO : operands())
890     if (MO.isReg())
891       MRI.removeRegOperandFromUseList(&MO);
892 }
893 
894 /// AddRegOperandsToUseLists - Add all of the register operands in
895 /// this instruction from their respective use lists.  This requires that the
896 /// operands not be on their use lists yet.
897 void MachineInstr::AddRegOperandsToUseLists(MachineRegisterInfo &MRI) {
898   for (MachineOperand &MO : operands())
899     if (MO.isReg())
900       MRI.addRegOperandToUseList(&MO);
901 }
902 
903 void MachineInstr::addOperand(const MachineOperand &Op) {
904   MachineBasicBlock *MBB = getParent();
905   assert(MBB && "Use MachineInstrBuilder to add operands to dangling instrs");
906   MachineFunction *MF = MBB->getParent();
907   assert(MF && "Use MachineInstrBuilder to add operands to dangling instrs");
908   addOperand(*MF, Op);
909 }
910 
911 /// Move NumOps MachineOperands from Src to Dst, with support for overlapping
912 /// ranges. If MRI is non-null also update use-def chains.
913 static void moveOperands(MachineOperand *Dst, MachineOperand *Src,
914                          unsigned NumOps, MachineRegisterInfo *MRI) {
915   if (MRI)
916     return MRI->moveOperands(Dst, Src, NumOps);
917 
918   // MachineOperand is a trivially copyable type so we can just use memmove.
919   std::memmove(Dst, Src, NumOps * sizeof(MachineOperand));
920 }
921 
922 /// addOperand - Add the specified operand to the instruction.  If it is an
923 /// implicit operand, it is added to the end of the operand list.  If it is
924 /// an explicit operand it is added at the end of the explicit operand list
925 /// (before the first implicit operand).
926 void MachineInstr::addOperand(MachineFunction &MF, const MachineOperand &Op) {
927   assert(MCID && "Cannot add operands before providing an instr descriptor");
928 
929   // Check if we're adding one of our existing operands.
930   if (&Op >= Operands && &Op < Operands + NumOperands) {
931     // This is unusual: MI->addOperand(MI->getOperand(i)).
932     // If adding Op requires reallocating or moving existing operands around,
933     // the Op reference could go stale. Support it by copying Op.
934     MachineOperand CopyOp(Op);
935     return addOperand(MF, CopyOp);
936   }
937 
938   // Find the insert location for the new operand.  Implicit registers go at
939   // the end, everything else goes before the implicit regs.
940   //
941   // FIXME: Allow mixed explicit and implicit operands on inline asm.
942   // InstrEmitter::EmitSpecialNode() is marking inline asm clobbers as
943   // implicit-defs, but they must not be moved around.  See the FIXME in
944   // InstrEmitter.cpp.
945   unsigned OpNo = getNumOperands();
946   bool isImpReg = Op.isReg() && Op.isImplicit();
947   if (!isImpReg && !isInlineAsm()) {
948     while (OpNo && Operands[OpNo-1].isReg() && Operands[OpNo-1].isImplicit()) {
949       --OpNo;
950       assert(!Operands[OpNo].isTied() && "Cannot move tied operands");
951     }
952   }
953 
954 #ifndef NDEBUG
955   bool isMetaDataOp = Op.getType() == MachineOperand::MO_Metadata;
956   // OpNo now points as the desired insertion point.  Unless this is a variadic
957   // instruction, only implicit regs are allowed beyond MCID->getNumOperands().
958   // RegMask operands go between the explicit and implicit operands.
959   assert((isImpReg || Op.isRegMask() || MCID->isVariadic() ||
960           OpNo < MCID->getNumOperands() || isMetaDataOp) &&
961          "Trying to add an operand to a machine instr that is already done!");
962 #endif
963 
964   MachineRegisterInfo *MRI = getRegInfo();
965 
966   // Determine if the Operands array needs to be reallocated.
967   // Save the old capacity and operand array.
968   OperandCapacity OldCap = CapOperands;
969   MachineOperand *OldOperands = Operands;
970   if (!OldOperands || OldCap.getSize() == getNumOperands()) {
971     CapOperands = OldOperands ? OldCap.getNext() : OldCap.get(1);
972     Operands = MF.allocateOperandArray(CapOperands);
973     // Move the operands before the insertion point.
974     if (OpNo)
975       moveOperands(Operands, OldOperands, OpNo, MRI);
976   }
977 
978   // Move the operands following the insertion point.
979   if (OpNo != NumOperands)
980     moveOperands(Operands + OpNo + 1, OldOperands + OpNo, NumOperands - OpNo,
981                  MRI);
982   ++NumOperands;
983 
984   // Deallocate the old operand array.
985   if (OldOperands != Operands && OldOperands)
986     MF.deallocateOperandArray(OldCap, OldOperands);
987 
988   // Copy Op into place. It still needs to be inserted into the MRI use lists.
989   MachineOperand *NewMO = new (Operands + OpNo) MachineOperand(Op);
990   NewMO->ParentMI = this;
991 
992   // When adding a register operand, tell MRI about it.
993   if (NewMO->isReg()) {
994     // Ensure isOnRegUseList() returns false, regardless of Op's status.
995     NewMO->Contents.Reg.Prev = nullptr;
996     // Ignore existing ties. This is not a property that can be copied.
997     NewMO->TiedTo = 0;
998     // Add the new operand to MRI, but only for instructions in an MBB.
999     if (MRI)
1000       MRI->addRegOperandToUseList(NewMO);
1001     // The MCID operand information isn't accurate until we start adding
1002     // explicit operands. The implicit operands are added first, then the
1003     // explicits are inserted before them.
1004     if (!isImpReg) {
1005       // Tie uses to defs as indicated in MCInstrDesc.
1006       if (NewMO->isUse()) {
1007         int DefIdx = MCID->getOperandConstraint(OpNo, MCOI::TIED_TO);
1008         if (DefIdx != -1)
1009           tieOperands(DefIdx, OpNo);
1010       }
1011       // If the register operand is flagged as early, mark the operand as such.
1012       if (MCID->getOperandConstraint(OpNo, MCOI::EARLY_CLOBBER) != -1)
1013         NewMO->setIsEarlyClobber(true);
1014     }
1015   }
1016 }
1017 
1018 /// RemoveOperand - Erase an operand  from an instruction, leaving it with one
1019 /// fewer operand than it started with.
1020 ///
1021 void MachineInstr::RemoveOperand(unsigned OpNo) {
1022   assert(OpNo < getNumOperands() && "Invalid operand number");
1023   untieRegOperand(OpNo);
1024 
1025 #ifndef NDEBUG
1026   // Moving tied operands would break the ties.
1027   for (unsigned i = OpNo + 1, e = getNumOperands(); i != e; ++i)
1028     if (Operands[i].isReg())
1029       assert(!Operands[i].isTied() && "Cannot move tied operands");
1030 #endif
1031 
1032   MachineRegisterInfo *MRI = getRegInfo();
1033   if (MRI && Operands[OpNo].isReg())
1034     MRI->removeRegOperandFromUseList(Operands + OpNo);
1035 
1036   // Don't call the MachineOperand destructor. A lot of this code depends on
1037   // MachineOperand having a trivial destructor anyway, and adding a call here
1038   // wouldn't make it 'destructor-correct'.
1039 
1040   if (unsigned N = NumOperands - 1 - OpNo)
1041     moveOperands(Operands + OpNo, Operands + OpNo + 1, N, MRI);
1042   --NumOperands;
1043 }
1044 
1045 /// addMemOperand - Add a MachineMemOperand to the machine instruction.
1046 /// This function should be used only occasionally. The setMemRefs function
1047 /// is the primary method for setting up a MachineInstr's MemRefs list.
1048 void MachineInstr::addMemOperand(MachineFunction &MF,
1049                                  MachineMemOperand *MO) {
1050   mmo_iterator OldMemRefs = MemRefs;
1051   unsigned OldNumMemRefs = NumMemRefs;
1052 
1053   unsigned NewNum = NumMemRefs + 1;
1054   mmo_iterator NewMemRefs = MF.allocateMemRefsArray(NewNum);
1055 
1056   std::copy(OldMemRefs, OldMemRefs + OldNumMemRefs, NewMemRefs);
1057   NewMemRefs[NewNum - 1] = MO;
1058   setMemRefs(NewMemRefs, NewMemRefs + NewNum);
1059 }
1060 
1061 /// Check to see if the MMOs pointed to by the two MemRefs arrays are
1062 /// identical.
1063 static bool hasIdenticalMMOs(const MachineInstr &MI1, const MachineInstr &MI2) {
1064   auto I1 = MI1.memoperands_begin(), E1 = MI1.memoperands_end();
1065   auto I2 = MI2.memoperands_begin(), E2 = MI2.memoperands_end();
1066   if ((E1 - I1) != (E2 - I2))
1067     return false;
1068   for (; I1 != E1; ++I1, ++I2) {
1069     if (**I1 != **I2)
1070       return false;
1071   }
1072   return true;
1073 }
1074 
1075 std::pair<MachineInstr::mmo_iterator, unsigned>
1076 MachineInstr::mergeMemRefsWith(const MachineInstr& Other) {
1077 
1078   // If either of the incoming memrefs are empty, we must be conservative and
1079   // treat this as if we've exhausted our space for memrefs and dropped them.
1080   if (memoperands_empty() || Other.memoperands_empty())
1081     return std::make_pair(nullptr, 0);
1082 
1083   // If both instructions have identical memrefs, we don't need to merge them.
1084   // Since many instructions have a single memref, and we tend to merge things
1085   // like pairs of loads from the same location, this catches a large number of
1086   // cases in practice.
1087   if (hasIdenticalMMOs(*this, Other))
1088     return std::make_pair(MemRefs, NumMemRefs);
1089 
1090   // TODO: consider uniquing elements within the operand lists to reduce
1091   // space usage and fall back to conservative information less often.
1092   size_t CombinedNumMemRefs = NumMemRefs + Other.NumMemRefs;
1093 
1094   // If we don't have enough room to store this many memrefs, be conservative
1095   // and drop them.  Otherwise, we'd fail asserts when trying to add them to
1096   // the new instruction.
1097   if (CombinedNumMemRefs != uint8_t(CombinedNumMemRefs))
1098     return std::make_pair(nullptr, 0);
1099 
1100   MachineFunction *MF = getMF();
1101   mmo_iterator MemBegin = MF->allocateMemRefsArray(CombinedNumMemRefs);
1102   mmo_iterator MemEnd = std::copy(memoperands_begin(), memoperands_end(),
1103                                   MemBegin);
1104   MemEnd = std::copy(Other.memoperands_begin(), Other.memoperands_end(),
1105                      MemEnd);
1106   assert(MemEnd - MemBegin == (ptrdiff_t)CombinedNumMemRefs &&
1107          "missing memrefs");
1108 
1109   return std::make_pair(MemBegin, CombinedNumMemRefs);
1110 }
1111 
1112 bool MachineInstr::hasPropertyInBundle(unsigned Mask, QueryType Type) const {
1113   assert(!isBundledWithPred() && "Must be called on bundle header");
1114   for (MachineBasicBlock::const_instr_iterator MII = getIterator();; ++MII) {
1115     if (MII->getDesc().getFlags() & Mask) {
1116       if (Type == AnyInBundle)
1117         return true;
1118     } else {
1119       if (Type == AllInBundle && !MII->isBundle())
1120         return false;
1121     }
1122     // This was the last instruction in the bundle.
1123     if (!MII->isBundledWithSucc())
1124       return Type == AllInBundle;
1125   }
1126 }
1127 
1128 bool MachineInstr::isIdenticalTo(const MachineInstr &Other,
1129                                  MICheckType Check) const {
1130   // If opcodes or number of operands are not the same then the two
1131   // instructions are obviously not identical.
1132   if (Other.getOpcode() != getOpcode() ||
1133       Other.getNumOperands() != getNumOperands())
1134     return false;
1135 
1136   if (isBundle()) {
1137     // We have passed the test above that both instructions have the same
1138     // opcode, so we know that both instructions are bundles here. Let's compare
1139     // MIs inside the bundle.
1140     assert(Other.isBundle() && "Expected that both instructions are bundles.");
1141     MachineBasicBlock::const_instr_iterator I1 = getIterator();
1142     MachineBasicBlock::const_instr_iterator I2 = Other.getIterator();
1143     // Loop until we analysed the last intruction inside at least one of the
1144     // bundles.
1145     while (I1->isBundledWithSucc() && I2->isBundledWithSucc()) {
1146       ++I1;
1147       ++I2;
1148       if (!I1->isIdenticalTo(*I2, Check))
1149         return false;
1150     }
1151     // If we've reached the end of just one of the two bundles, but not both,
1152     // the instructions are not identical.
1153     if (I1->isBundledWithSucc() || I2->isBundledWithSucc())
1154       return false;
1155   }
1156 
1157   // Check operands to make sure they match.
1158   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1159     const MachineOperand &MO = getOperand(i);
1160     const MachineOperand &OMO = Other.getOperand(i);
1161     if (!MO.isReg()) {
1162       if (!MO.isIdenticalTo(OMO))
1163         return false;
1164       continue;
1165     }
1166 
1167     // Clients may or may not want to ignore defs when testing for equality.
1168     // For example, machine CSE pass only cares about finding common
1169     // subexpressions, so it's safe to ignore virtual register defs.
1170     if (MO.isDef()) {
1171       if (Check == IgnoreDefs)
1172         continue;
1173       else if (Check == IgnoreVRegDefs) {
1174         if (!TargetRegisterInfo::isVirtualRegister(MO.getReg()) ||
1175             !TargetRegisterInfo::isVirtualRegister(OMO.getReg()))
1176           if (!MO.isIdenticalTo(OMO))
1177             return false;
1178       } else {
1179         if (!MO.isIdenticalTo(OMO))
1180           return false;
1181         if (Check == CheckKillDead && MO.isDead() != OMO.isDead())
1182           return false;
1183       }
1184     } else {
1185       if (!MO.isIdenticalTo(OMO))
1186         return false;
1187       if (Check == CheckKillDead && MO.isKill() != OMO.isKill())
1188         return false;
1189     }
1190   }
1191   // If DebugLoc does not match then two dbg.values are not identical.
1192   if (isDebugValue())
1193     if (getDebugLoc() && Other.getDebugLoc() &&
1194         getDebugLoc() != Other.getDebugLoc())
1195       return false;
1196   return true;
1197 }
1198 
1199 const MachineFunction *MachineInstr::getMF() const {
1200   return getParent()->getParent();
1201 }
1202 
1203 MachineInstr *MachineInstr::removeFromParent() {
1204   assert(getParent() && "Not embedded in a basic block!");
1205   return getParent()->remove(this);
1206 }
1207 
1208 MachineInstr *MachineInstr::removeFromBundle() {
1209   assert(getParent() && "Not embedded in a basic block!");
1210   return getParent()->remove_instr(this);
1211 }
1212 
1213 void MachineInstr::eraseFromParent() {
1214   assert(getParent() && "Not embedded in a basic block!");
1215   getParent()->erase(this);
1216 }
1217 
1218 void MachineInstr::eraseFromParentAndMarkDBGValuesForRemoval() {
1219   assert(getParent() && "Not embedded in a basic block!");
1220   MachineBasicBlock *MBB = getParent();
1221   MachineFunction *MF = MBB->getParent();
1222   assert(MF && "Not embedded in a function!");
1223 
1224   MachineInstr *MI = (MachineInstr *)this;
1225   MachineRegisterInfo &MRI = MF->getRegInfo();
1226 
1227   for (const MachineOperand &MO : MI->operands()) {
1228     if (!MO.isReg() || !MO.isDef())
1229       continue;
1230     unsigned Reg = MO.getReg();
1231     if (!TargetRegisterInfo::isVirtualRegister(Reg))
1232       continue;
1233     MRI.markUsesInDebugValueAsUndef(Reg);
1234   }
1235   MI->eraseFromParent();
1236 }
1237 
1238 void MachineInstr::eraseFromBundle() {
1239   assert(getParent() && "Not embedded in a basic block!");
1240   getParent()->erase_instr(this);
1241 }
1242 
1243 /// getNumExplicitOperands - Returns the number of non-implicit operands.
1244 ///
1245 unsigned MachineInstr::getNumExplicitOperands() const {
1246   unsigned NumOperands = MCID->getNumOperands();
1247   if (!MCID->isVariadic())
1248     return NumOperands;
1249 
1250   for (unsigned i = NumOperands, e = getNumOperands(); i != e; ++i) {
1251     const MachineOperand &MO = getOperand(i);
1252     if (!MO.isReg() || !MO.isImplicit())
1253       NumOperands++;
1254   }
1255   return NumOperands;
1256 }
1257 
1258 void MachineInstr::bundleWithPred() {
1259   assert(!isBundledWithPred() && "MI is already bundled with its predecessor");
1260   setFlag(BundledPred);
1261   MachineBasicBlock::instr_iterator Pred = getIterator();
1262   --Pred;
1263   assert(!Pred->isBundledWithSucc() && "Inconsistent bundle flags");
1264   Pred->setFlag(BundledSucc);
1265 }
1266 
1267 void MachineInstr::bundleWithSucc() {
1268   assert(!isBundledWithSucc() && "MI is already bundled with its successor");
1269   setFlag(BundledSucc);
1270   MachineBasicBlock::instr_iterator Succ = getIterator();
1271   ++Succ;
1272   assert(!Succ->isBundledWithPred() && "Inconsistent bundle flags");
1273   Succ->setFlag(BundledPred);
1274 }
1275 
1276 void MachineInstr::unbundleFromPred() {
1277   assert(isBundledWithPred() && "MI isn't bundled with its predecessor");
1278   clearFlag(BundledPred);
1279   MachineBasicBlock::instr_iterator Pred = getIterator();
1280   --Pred;
1281   assert(Pred->isBundledWithSucc() && "Inconsistent bundle flags");
1282   Pred->clearFlag(BundledSucc);
1283 }
1284 
1285 void MachineInstr::unbundleFromSucc() {
1286   assert(isBundledWithSucc() && "MI isn't bundled with its successor");
1287   clearFlag(BundledSucc);
1288   MachineBasicBlock::instr_iterator Succ = getIterator();
1289   ++Succ;
1290   assert(Succ->isBundledWithPred() && "Inconsistent bundle flags");
1291   Succ->clearFlag(BundledPred);
1292 }
1293 
1294 bool MachineInstr::isStackAligningInlineAsm() const {
1295   if (isInlineAsm()) {
1296     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1297     if (ExtraInfo & InlineAsm::Extra_IsAlignStack)
1298       return true;
1299   }
1300   return false;
1301 }
1302 
1303 InlineAsm::AsmDialect MachineInstr::getInlineAsmDialect() const {
1304   assert(isInlineAsm() && "getInlineAsmDialect() only works for inline asms!");
1305   unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1306   return InlineAsm::AsmDialect((ExtraInfo & InlineAsm::Extra_AsmDialect) != 0);
1307 }
1308 
1309 int MachineInstr::findInlineAsmFlagIdx(unsigned OpIdx,
1310                                        unsigned *GroupNo) const {
1311   assert(isInlineAsm() && "Expected an inline asm instruction");
1312   assert(OpIdx < getNumOperands() && "OpIdx out of range");
1313 
1314   // Ignore queries about the initial operands.
1315   if (OpIdx < InlineAsm::MIOp_FirstOperand)
1316     return -1;
1317 
1318   unsigned Group = 0;
1319   unsigned NumOps;
1320   for (unsigned i = InlineAsm::MIOp_FirstOperand, e = getNumOperands(); i < e;
1321        i += NumOps) {
1322     const MachineOperand &FlagMO = getOperand(i);
1323     // If we reach the implicit register operands, stop looking.
1324     if (!FlagMO.isImm())
1325       return -1;
1326     NumOps = 1 + InlineAsm::getNumOperandRegisters(FlagMO.getImm());
1327     if (i + NumOps > OpIdx) {
1328       if (GroupNo)
1329         *GroupNo = Group;
1330       return i;
1331     }
1332     ++Group;
1333   }
1334   return -1;
1335 }
1336 
1337 const DILocalVariable *MachineInstr::getDebugVariable() const {
1338   assert(isDebugValue() && "not a DBG_VALUE");
1339   return cast<DILocalVariable>(getOperand(2).getMetadata());
1340 }
1341 
1342 const DIExpression *MachineInstr::getDebugExpression() const {
1343   assert(isDebugValue() && "not a DBG_VALUE");
1344   return cast<DIExpression>(getOperand(3).getMetadata());
1345 }
1346 
1347 const TargetRegisterClass*
1348 MachineInstr::getRegClassConstraint(unsigned OpIdx,
1349                                     const TargetInstrInfo *TII,
1350                                     const TargetRegisterInfo *TRI) const {
1351   assert(getParent() && "Can't have an MBB reference here!");
1352   assert(getMF() && "Can't have an MF reference here!");
1353   const MachineFunction &MF = *getMF();
1354 
1355   // Most opcodes have fixed constraints in their MCInstrDesc.
1356   if (!isInlineAsm())
1357     return TII->getRegClass(getDesc(), OpIdx, TRI, MF);
1358 
1359   if (!getOperand(OpIdx).isReg())
1360     return nullptr;
1361 
1362   // For tied uses on inline asm, get the constraint from the def.
1363   unsigned DefIdx;
1364   if (getOperand(OpIdx).isUse() && isRegTiedToDefOperand(OpIdx, &DefIdx))
1365     OpIdx = DefIdx;
1366 
1367   // Inline asm stores register class constraints in the flag word.
1368   int FlagIdx = findInlineAsmFlagIdx(OpIdx);
1369   if (FlagIdx < 0)
1370     return nullptr;
1371 
1372   unsigned Flag = getOperand(FlagIdx).getImm();
1373   unsigned RCID;
1374   if ((InlineAsm::getKind(Flag) == InlineAsm::Kind_RegUse ||
1375        InlineAsm::getKind(Flag) == InlineAsm::Kind_RegDef ||
1376        InlineAsm::getKind(Flag) == InlineAsm::Kind_RegDefEarlyClobber) &&
1377       InlineAsm::hasRegClassConstraint(Flag, RCID))
1378     return TRI->getRegClass(RCID);
1379 
1380   // Assume that all registers in a memory operand are pointers.
1381   if (InlineAsm::getKind(Flag) == InlineAsm::Kind_Mem)
1382     return TRI->getPointerRegClass(MF);
1383 
1384   return nullptr;
1385 }
1386 
1387 const TargetRegisterClass *MachineInstr::getRegClassConstraintEffectForVReg(
1388     unsigned Reg, const TargetRegisterClass *CurRC, const TargetInstrInfo *TII,
1389     const TargetRegisterInfo *TRI, bool ExploreBundle) const {
1390   // Check every operands inside the bundle if we have
1391   // been asked to.
1392   if (ExploreBundle)
1393     for (ConstMIBundleOperands OpndIt(*this); OpndIt.isValid() && CurRC;
1394          ++OpndIt)
1395       CurRC = OpndIt->getParent()->getRegClassConstraintEffectForVRegImpl(
1396           OpndIt.getOperandNo(), Reg, CurRC, TII, TRI);
1397   else
1398     // Otherwise, just check the current operands.
1399     for (unsigned i = 0, e = NumOperands; i < e && CurRC; ++i)
1400       CurRC = getRegClassConstraintEffectForVRegImpl(i, Reg, CurRC, TII, TRI);
1401   return CurRC;
1402 }
1403 
1404 const TargetRegisterClass *MachineInstr::getRegClassConstraintEffectForVRegImpl(
1405     unsigned OpIdx, unsigned Reg, const TargetRegisterClass *CurRC,
1406     const TargetInstrInfo *TII, const TargetRegisterInfo *TRI) const {
1407   assert(CurRC && "Invalid initial register class");
1408   // Check if Reg is constrained by some of its use/def from MI.
1409   const MachineOperand &MO = getOperand(OpIdx);
1410   if (!MO.isReg() || MO.getReg() != Reg)
1411     return CurRC;
1412   // If yes, accumulate the constraints through the operand.
1413   return getRegClassConstraintEffect(OpIdx, CurRC, TII, TRI);
1414 }
1415 
1416 const TargetRegisterClass *MachineInstr::getRegClassConstraintEffect(
1417     unsigned OpIdx, const TargetRegisterClass *CurRC,
1418     const TargetInstrInfo *TII, const TargetRegisterInfo *TRI) const {
1419   const TargetRegisterClass *OpRC = getRegClassConstraint(OpIdx, TII, TRI);
1420   const MachineOperand &MO = getOperand(OpIdx);
1421   assert(MO.isReg() &&
1422          "Cannot get register constraints for non-register operand");
1423   assert(CurRC && "Invalid initial register class");
1424   if (unsigned SubIdx = MO.getSubReg()) {
1425     if (OpRC)
1426       CurRC = TRI->getMatchingSuperRegClass(CurRC, OpRC, SubIdx);
1427     else
1428       CurRC = TRI->getSubClassWithSubReg(CurRC, SubIdx);
1429   } else if (OpRC)
1430     CurRC = TRI->getCommonSubClass(CurRC, OpRC);
1431   return CurRC;
1432 }
1433 
1434 /// Return the number of instructions inside the MI bundle, not counting the
1435 /// header instruction.
1436 unsigned MachineInstr::getBundleSize() const {
1437   MachineBasicBlock::const_instr_iterator I = getIterator();
1438   unsigned Size = 0;
1439   while (I->isBundledWithSucc()) {
1440     ++Size;
1441     ++I;
1442   }
1443   return Size;
1444 }
1445 
1446 /// Returns true if the MachineInstr has an implicit-use operand of exactly
1447 /// the given register (not considering sub/super-registers).
1448 bool MachineInstr::hasRegisterImplicitUseOperand(unsigned Reg) const {
1449   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1450     const MachineOperand &MO = getOperand(i);
1451     if (MO.isReg() && MO.isUse() && MO.isImplicit() && MO.getReg() == Reg)
1452       return true;
1453   }
1454   return false;
1455 }
1456 
1457 /// findRegisterUseOperandIdx() - Returns the MachineOperand that is a use of
1458 /// the specific register or -1 if it is not found. It further tightens
1459 /// the search criteria to a use that kills the register if isKill is true.
1460 int MachineInstr::findRegisterUseOperandIdx(
1461     unsigned Reg, bool isKill, const TargetRegisterInfo *TRI) const {
1462   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1463     const MachineOperand &MO = getOperand(i);
1464     if (!MO.isReg() || !MO.isUse())
1465       continue;
1466     unsigned MOReg = MO.getReg();
1467     if (!MOReg)
1468       continue;
1469     if (MOReg == Reg || (TRI && TargetRegisterInfo::isPhysicalRegister(MOReg) &&
1470                          TargetRegisterInfo::isPhysicalRegister(Reg) &&
1471                          TRI->isSubRegister(MOReg, Reg)))
1472       if (!isKill || MO.isKill())
1473         return i;
1474   }
1475   return -1;
1476 }
1477 
1478 /// readsWritesVirtualRegister - Return a pair of bools (reads, writes)
1479 /// indicating if this instruction reads or writes Reg. This also considers
1480 /// partial defines.
1481 std::pair<bool,bool>
1482 MachineInstr::readsWritesVirtualRegister(unsigned Reg,
1483                                          SmallVectorImpl<unsigned> *Ops) const {
1484   bool PartDef = false; // Partial redefine.
1485   bool FullDef = false; // Full define.
1486   bool Use = false;
1487 
1488   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1489     const MachineOperand &MO = getOperand(i);
1490     if (!MO.isReg() || MO.getReg() != Reg)
1491       continue;
1492     if (Ops)
1493       Ops->push_back(i);
1494     if (MO.isUse())
1495       Use |= !MO.isUndef();
1496     else if (MO.getSubReg() && !MO.isUndef())
1497       // A partial <def,undef> doesn't count as reading the register.
1498       PartDef = true;
1499     else
1500       FullDef = true;
1501   }
1502   // A partial redefine uses Reg unless there is also a full define.
1503   return std::make_pair(Use || (PartDef && !FullDef), PartDef || FullDef);
1504 }
1505 
1506 /// findRegisterDefOperandIdx() - Returns the operand index that is a def of
1507 /// the specified register or -1 if it is not found. If isDead is true, defs
1508 /// that are not dead are skipped. If TargetRegisterInfo is non-null, then it
1509 /// also checks if there is a def of a super-register.
1510 int
1511 MachineInstr::findRegisterDefOperandIdx(unsigned Reg, bool isDead, bool Overlap,
1512                                         const TargetRegisterInfo *TRI) const {
1513   bool isPhys = TargetRegisterInfo::isPhysicalRegister(Reg);
1514   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1515     const MachineOperand &MO = getOperand(i);
1516     // Accept regmask operands when Overlap is set.
1517     // Ignore them when looking for a specific def operand (Overlap == false).
1518     if (isPhys && Overlap && MO.isRegMask() && MO.clobbersPhysReg(Reg))
1519       return i;
1520     if (!MO.isReg() || !MO.isDef())
1521       continue;
1522     unsigned MOReg = MO.getReg();
1523     bool Found = (MOReg == Reg);
1524     if (!Found && TRI && isPhys &&
1525         TargetRegisterInfo::isPhysicalRegister(MOReg)) {
1526       if (Overlap)
1527         Found = TRI->regsOverlap(MOReg, Reg);
1528       else
1529         Found = TRI->isSubRegister(MOReg, Reg);
1530     }
1531     if (Found && (!isDead || MO.isDead()))
1532       return i;
1533   }
1534   return -1;
1535 }
1536 
1537 /// findFirstPredOperandIdx() - Find the index of the first operand in the
1538 /// operand list that is used to represent the predicate. It returns -1 if
1539 /// none is found.
1540 int MachineInstr::findFirstPredOperandIdx() const {
1541   // Don't call MCID.findFirstPredOperandIdx() because this variant
1542   // is sometimes called on an instruction that's not yet complete, and
1543   // so the number of operands is less than the MCID indicates. In
1544   // particular, the PTX target does this.
1545   const MCInstrDesc &MCID = getDesc();
1546   if (MCID.isPredicable()) {
1547     for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
1548       if (MCID.OpInfo[i].isPredicate())
1549         return i;
1550   }
1551 
1552   return -1;
1553 }
1554 
1555 // MachineOperand::TiedTo is 4 bits wide.
1556 const unsigned TiedMax = 15;
1557 
1558 /// tieOperands - Mark operands at DefIdx and UseIdx as tied to each other.
1559 ///
1560 /// Use and def operands can be tied together, indicated by a non-zero TiedTo
1561 /// field. TiedTo can have these values:
1562 ///
1563 /// 0:              Operand is not tied to anything.
1564 /// 1 to TiedMax-1: Tied to getOperand(TiedTo-1).
1565 /// TiedMax:        Tied to an operand >= TiedMax-1.
1566 ///
1567 /// The tied def must be one of the first TiedMax operands on a normal
1568 /// instruction. INLINEASM instructions allow more tied defs.
1569 ///
1570 void MachineInstr::tieOperands(unsigned DefIdx, unsigned UseIdx) {
1571   MachineOperand &DefMO = getOperand(DefIdx);
1572   MachineOperand &UseMO = getOperand(UseIdx);
1573   assert(DefMO.isDef() && "DefIdx must be a def operand");
1574   assert(UseMO.isUse() && "UseIdx must be a use operand");
1575   assert(!DefMO.isTied() && "Def is already tied to another use");
1576   assert(!UseMO.isTied() && "Use is already tied to another def");
1577 
1578   if (DefIdx < TiedMax)
1579     UseMO.TiedTo = DefIdx + 1;
1580   else {
1581     // Inline asm can use the group descriptors to find tied operands, but on
1582     // normal instruction, the tied def must be within the first TiedMax
1583     // operands.
1584     assert(isInlineAsm() && "DefIdx out of range");
1585     UseMO.TiedTo = TiedMax;
1586   }
1587 
1588   // UseIdx can be out of range, we'll search for it in findTiedOperandIdx().
1589   DefMO.TiedTo = std::min(UseIdx + 1, TiedMax);
1590 }
1591 
1592 /// Given the index of a tied register operand, find the operand it is tied to.
1593 /// Defs are tied to uses and vice versa. Returns the index of the tied operand
1594 /// which must exist.
1595 unsigned MachineInstr::findTiedOperandIdx(unsigned OpIdx) const {
1596   const MachineOperand &MO = getOperand(OpIdx);
1597   assert(MO.isTied() && "Operand isn't tied");
1598 
1599   // Normally TiedTo is in range.
1600   if (MO.TiedTo < TiedMax)
1601     return MO.TiedTo - 1;
1602 
1603   // Uses on normal instructions can be out of range.
1604   if (!isInlineAsm()) {
1605     // Normal tied defs must be in the 0..TiedMax-1 range.
1606     if (MO.isUse())
1607       return TiedMax - 1;
1608     // MO is a def. Search for the tied use.
1609     for (unsigned i = TiedMax - 1, e = getNumOperands(); i != e; ++i) {
1610       const MachineOperand &UseMO = getOperand(i);
1611       if (UseMO.isReg() && UseMO.isUse() && UseMO.TiedTo == OpIdx + 1)
1612         return i;
1613     }
1614     llvm_unreachable("Can't find tied use");
1615   }
1616 
1617   // Now deal with inline asm by parsing the operand group descriptor flags.
1618   // Find the beginning of each operand group.
1619   SmallVector<unsigned, 8> GroupIdx;
1620   unsigned OpIdxGroup = ~0u;
1621   unsigned NumOps;
1622   for (unsigned i = InlineAsm::MIOp_FirstOperand, e = getNumOperands(); i < e;
1623        i += NumOps) {
1624     const MachineOperand &FlagMO = getOperand(i);
1625     assert(FlagMO.isImm() && "Invalid tied operand on inline asm");
1626     unsigned CurGroup = GroupIdx.size();
1627     GroupIdx.push_back(i);
1628     NumOps = 1 + InlineAsm::getNumOperandRegisters(FlagMO.getImm());
1629     // OpIdx belongs to this operand group.
1630     if (OpIdx > i && OpIdx < i + NumOps)
1631       OpIdxGroup = CurGroup;
1632     unsigned TiedGroup;
1633     if (!InlineAsm::isUseOperandTiedToDef(FlagMO.getImm(), TiedGroup))
1634       continue;
1635     // Operands in this group are tied to operands in TiedGroup which must be
1636     // earlier. Find the number of operands between the two groups.
1637     unsigned Delta = i - GroupIdx[TiedGroup];
1638 
1639     // OpIdx is a use tied to TiedGroup.
1640     if (OpIdxGroup == CurGroup)
1641       return OpIdx - Delta;
1642 
1643     // OpIdx is a def tied to this use group.
1644     if (OpIdxGroup == TiedGroup)
1645       return OpIdx + Delta;
1646   }
1647   llvm_unreachable("Invalid tied operand on inline asm");
1648 }
1649 
1650 /// clearKillInfo - Clears kill flags on all operands.
1651 ///
1652 void MachineInstr::clearKillInfo() {
1653   for (MachineOperand &MO : operands()) {
1654     if (MO.isReg() && MO.isUse())
1655       MO.setIsKill(false);
1656   }
1657 }
1658 
1659 void MachineInstr::substituteRegister(unsigned FromReg,
1660                                       unsigned ToReg,
1661                                       unsigned SubIdx,
1662                                       const TargetRegisterInfo &RegInfo) {
1663   if (TargetRegisterInfo::isPhysicalRegister(ToReg)) {
1664     if (SubIdx)
1665       ToReg = RegInfo.getSubReg(ToReg, SubIdx);
1666     for (MachineOperand &MO : operands()) {
1667       if (!MO.isReg() || MO.getReg() != FromReg)
1668         continue;
1669       MO.substPhysReg(ToReg, RegInfo);
1670     }
1671   } else {
1672     for (MachineOperand &MO : operands()) {
1673       if (!MO.isReg() || MO.getReg() != FromReg)
1674         continue;
1675       MO.substVirtReg(ToReg, SubIdx, RegInfo);
1676     }
1677   }
1678 }
1679 
1680 /// isSafeToMove - Return true if it is safe to move this instruction. If
1681 /// SawStore is set to true, it means that there is a store (or call) between
1682 /// the instruction's location and its intended destination.
1683 bool MachineInstr::isSafeToMove(AliasAnalysis *AA, bool &SawStore) const {
1684   // Ignore stuff that we obviously can't move.
1685   //
1686   // Treat volatile loads as stores. This is not strictly necessary for
1687   // volatiles, but it is required for atomic loads. It is not allowed to move
1688   // a load across an atomic load with Ordering > Monotonic.
1689   if (mayStore() || isCall() ||
1690       (mayLoad() && hasOrderedMemoryRef())) {
1691     SawStore = true;
1692     return false;
1693   }
1694 
1695   if (isPosition() || isDebugValue() || isTerminator() ||
1696       hasUnmodeledSideEffects())
1697     return false;
1698 
1699   // See if this instruction does a load.  If so, we have to guarantee that the
1700   // loaded value doesn't change between the load and the its intended
1701   // destination. The check for isInvariantLoad gives the targe the chance to
1702   // classify the load as always returning a constant, e.g. a constant pool
1703   // load.
1704   if (mayLoad() && !isDereferenceableInvariantLoad(AA))
1705     // Otherwise, this is a real load.  If there is a store between the load and
1706     // end of block, we can't move it.
1707     return !SawStore;
1708 
1709   return true;
1710 }
1711 
1712 bool MachineInstr::mayAlias(AliasAnalysis *AA, MachineInstr &Other,
1713                             bool UseTBAA) {
1714   const MachineFunction *MF = getMF();
1715   const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
1716   const MachineFrameInfo &MFI = MF->getFrameInfo();
1717 
1718   // If neither instruction stores to memory, they can't alias in any
1719   // meaningful way, even if they read from the same address.
1720   if (!mayStore() && !Other.mayStore())
1721     return false;
1722 
1723   // Let the target decide if memory accesses cannot possibly overlap.
1724   if (TII->areMemAccessesTriviallyDisjoint(*this, Other, AA))
1725     return false;
1726 
1727   // FIXME: Need to handle multiple memory operands to support all targets.
1728   if (!hasOneMemOperand() || !Other.hasOneMemOperand())
1729     return true;
1730 
1731   MachineMemOperand *MMOa = *memoperands_begin();
1732   MachineMemOperand *MMOb = *Other.memoperands_begin();
1733 
1734   // The following interface to AA is fashioned after DAGCombiner::isAlias
1735   // and operates with MachineMemOperand offset with some important
1736   // assumptions:
1737   //   - LLVM fundamentally assumes flat address spaces.
1738   //   - MachineOperand offset can *only* result from legalization and
1739   //     cannot affect queries other than the trivial case of overlap
1740   //     checking.
1741   //   - These offsets never wrap and never step outside
1742   //     of allocated objects.
1743   //   - There should never be any negative offsets here.
1744   //
1745   // FIXME: Modify API to hide this math from "user"
1746   // Even before we go to AA we can reason locally about some
1747   // memory objects. It can save compile time, and possibly catch some
1748   // corner cases not currently covered.
1749 
1750   int64_t OffsetA = MMOa->getOffset();
1751   int64_t OffsetB = MMOb->getOffset();
1752 
1753   int64_t MinOffset = std::min(OffsetA, OffsetB);
1754   int64_t WidthA = MMOa->getSize();
1755   int64_t WidthB = MMOb->getSize();
1756   const Value *ValA = MMOa->getValue();
1757   const Value *ValB = MMOb->getValue();
1758   bool SameVal = (ValA && ValB && (ValA == ValB));
1759   if (!SameVal) {
1760     const PseudoSourceValue *PSVa = MMOa->getPseudoValue();
1761     const PseudoSourceValue *PSVb = MMOb->getPseudoValue();
1762     if (PSVa && ValB && !PSVa->mayAlias(&MFI))
1763       return false;
1764     if (PSVb && ValA && !PSVb->mayAlias(&MFI))
1765       return false;
1766     if (PSVa && PSVb && (PSVa == PSVb))
1767       SameVal = true;
1768   }
1769 
1770   if (SameVal) {
1771     int64_t MaxOffset = std::max(OffsetA, OffsetB);
1772     int64_t LowWidth = (MinOffset == OffsetA) ? WidthA : WidthB;
1773     return (MinOffset + LowWidth > MaxOffset);
1774   }
1775 
1776   if (!AA)
1777     return true;
1778 
1779   if (!ValA || !ValB)
1780     return true;
1781 
1782   assert((OffsetA >= 0) && "Negative MachineMemOperand offset");
1783   assert((OffsetB >= 0) && "Negative MachineMemOperand offset");
1784 
1785   int64_t Overlapa = WidthA + OffsetA - MinOffset;
1786   int64_t Overlapb = WidthB + OffsetB - MinOffset;
1787 
1788   AliasResult AAResult = AA->alias(
1789       MemoryLocation(ValA, Overlapa,
1790                      UseTBAA ? MMOa->getAAInfo() : AAMDNodes()),
1791       MemoryLocation(ValB, Overlapb,
1792                      UseTBAA ? MMOb->getAAInfo() : AAMDNodes()));
1793 
1794   return (AAResult != NoAlias);
1795 }
1796 
1797 /// hasOrderedMemoryRef - Return true if this instruction may have an ordered
1798 /// or volatile memory reference, or if the information describing the memory
1799 /// reference is not available. Return false if it is known to have no ordered
1800 /// memory references.
1801 bool MachineInstr::hasOrderedMemoryRef() const {
1802   // An instruction known never to access memory won't have a volatile access.
1803   if (!mayStore() &&
1804       !mayLoad() &&
1805       !isCall() &&
1806       !hasUnmodeledSideEffects())
1807     return false;
1808 
1809   // Otherwise, if the instruction has no memory reference information,
1810   // conservatively assume it wasn't preserved.
1811   if (memoperands_empty())
1812     return true;
1813 
1814   // Check if any of our memory operands are ordered.
1815   return llvm::any_of(memoperands(), [](const MachineMemOperand *MMO) {
1816     return !MMO->isUnordered();
1817   });
1818 }
1819 
1820 /// isDereferenceableInvariantLoad - Return true if this instruction will never
1821 /// trap and is loading from a location whose value is invariant across a run of
1822 /// this function.
1823 bool MachineInstr::isDereferenceableInvariantLoad(AliasAnalysis *AA) const {
1824   // If the instruction doesn't load at all, it isn't an invariant load.
1825   if (!mayLoad())
1826     return false;
1827 
1828   // If the instruction has lost its memoperands, conservatively assume that
1829   // it may not be an invariant load.
1830   if (memoperands_empty())
1831     return false;
1832 
1833   const MachineFrameInfo &MFI = getParent()->getParent()->getFrameInfo();
1834 
1835   for (MachineMemOperand *MMO : memoperands()) {
1836     if (MMO->isVolatile()) return false;
1837     if (MMO->isStore()) return false;
1838     if (MMO->isInvariant() && MMO->isDereferenceable())
1839       continue;
1840 
1841     // A load from a constant PseudoSourceValue is invariant.
1842     if (const PseudoSourceValue *PSV = MMO->getPseudoValue())
1843       if (PSV->isConstant(&MFI))
1844         continue;
1845 
1846     if (const Value *V = MMO->getValue()) {
1847       // If we have an AliasAnalysis, ask it whether the memory is constant.
1848       if (AA &&
1849           AA->pointsToConstantMemory(
1850               MemoryLocation(V, MMO->getSize(), MMO->getAAInfo())))
1851         continue;
1852     }
1853 
1854     // Otherwise assume conservatively.
1855     return false;
1856   }
1857 
1858   // Everything checks out.
1859   return true;
1860 }
1861 
1862 /// isConstantValuePHI - If the specified instruction is a PHI that always
1863 /// merges together the same virtual register, return the register, otherwise
1864 /// return 0.
1865 unsigned MachineInstr::isConstantValuePHI() const {
1866   if (!isPHI())
1867     return 0;
1868   assert(getNumOperands() >= 3 &&
1869          "It's illegal to have a PHI without source operands");
1870 
1871   unsigned Reg = getOperand(1).getReg();
1872   for (unsigned i = 3, e = getNumOperands(); i < e; i += 2)
1873     if (getOperand(i).getReg() != Reg)
1874       return 0;
1875   return Reg;
1876 }
1877 
1878 bool MachineInstr::hasUnmodeledSideEffects() const {
1879   if (hasProperty(MCID::UnmodeledSideEffects))
1880     return true;
1881   if (isInlineAsm()) {
1882     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1883     if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
1884       return true;
1885   }
1886 
1887   return false;
1888 }
1889 
1890 bool MachineInstr::isLoadFoldBarrier() const {
1891   return mayStore() || isCall() || hasUnmodeledSideEffects();
1892 }
1893 
1894 /// allDefsAreDead - Return true if all the defs of this instruction are dead.
1895 ///
1896 bool MachineInstr::allDefsAreDead() const {
1897   for (const MachineOperand &MO : operands()) {
1898     if (!MO.isReg() || MO.isUse())
1899       continue;
1900     if (!MO.isDead())
1901       return false;
1902   }
1903   return true;
1904 }
1905 
1906 /// copyImplicitOps - Copy implicit register operands from specified
1907 /// instruction to this instruction.
1908 void MachineInstr::copyImplicitOps(MachineFunction &MF,
1909                                    const MachineInstr &MI) {
1910   for (unsigned i = MI.getDesc().getNumOperands(), e = MI.getNumOperands();
1911        i != e; ++i) {
1912     const MachineOperand &MO = MI.getOperand(i);
1913     if ((MO.isReg() && MO.isImplicit()) || MO.isRegMask())
1914       addOperand(MF, MO);
1915   }
1916 }
1917 
1918 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
1919 LLVM_DUMP_METHOD void MachineInstr::dump() const {
1920   dbgs() << "  ";
1921   print(dbgs());
1922 }
1923 #endif
1924 
1925 void MachineInstr::print(raw_ostream &OS, bool SkipOpers, bool SkipDebugLoc,
1926                          const TargetInstrInfo *TII) const {
1927   const Module *M = nullptr;
1928   if (const MachineBasicBlock *MBB = getParent())
1929     if (const MachineFunction *MF = MBB->getParent())
1930       M = MF->getFunction()->getParent();
1931 
1932   ModuleSlotTracker MST(M);
1933   print(OS, MST, SkipOpers, SkipDebugLoc, TII);
1934 }
1935 
1936 void MachineInstr::print(raw_ostream &OS, ModuleSlotTracker &MST,
1937                          bool SkipOpers, bool SkipDebugLoc,
1938                          const TargetInstrInfo *TII) const {
1939   // We can be a bit tidier if we know the MachineFunction.
1940   const MachineFunction *MF = nullptr;
1941   const TargetRegisterInfo *TRI = nullptr;
1942   const MachineRegisterInfo *MRI = nullptr;
1943   const TargetIntrinsicInfo *IntrinsicInfo = nullptr;
1944 
1945   if (const MachineBasicBlock *MBB = getParent()) {
1946     MF = MBB->getParent();
1947     if (MF) {
1948       MRI = &MF->getRegInfo();
1949       TRI = MF->getSubtarget().getRegisterInfo();
1950       if (!TII)
1951         TII = MF->getSubtarget().getInstrInfo();
1952       IntrinsicInfo = MF->getTarget().getIntrinsicInfo();
1953     }
1954   }
1955 
1956   // Save a list of virtual registers.
1957   SmallVector<unsigned, 8> VirtRegs;
1958 
1959   // Print explicitly defined operands on the left of an assignment syntax.
1960   unsigned StartOp = 0, e = getNumOperands();
1961   for (; StartOp < e && getOperand(StartOp).isReg() &&
1962          getOperand(StartOp).isDef() &&
1963          !getOperand(StartOp).isImplicit();
1964        ++StartOp) {
1965     if (StartOp != 0) OS << ", ";
1966     getOperand(StartOp).print(OS, MST, TRI, IntrinsicInfo);
1967     unsigned Reg = getOperand(StartOp).getReg();
1968     if (TargetRegisterInfo::isVirtualRegister(Reg)) {
1969       VirtRegs.push_back(Reg);
1970       LLT Ty = MRI ? MRI->getType(Reg) : LLT{};
1971       if (Ty.isValid())
1972         OS << '(' << Ty << ')';
1973     }
1974   }
1975 
1976   if (StartOp != 0)
1977     OS << " = ";
1978 
1979   // Print the opcode name.
1980   if (TII)
1981     OS << TII->getName(getOpcode());
1982   else
1983     OS << "UNKNOWN";
1984 
1985   if (SkipOpers)
1986     return;
1987 
1988   // Print the rest of the operands.
1989   bool FirstOp = true;
1990   unsigned AsmDescOp = ~0u;
1991   unsigned AsmOpCount = 0;
1992 
1993   if (isInlineAsm() && e >= InlineAsm::MIOp_FirstOperand) {
1994     // Print asm string.
1995     OS << " ";
1996     getOperand(InlineAsm::MIOp_AsmString).print(OS, MST, TRI);
1997 
1998     // Print HasSideEffects, MayLoad, MayStore, IsAlignStack
1999     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
2000     if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
2001       OS << " [sideeffect]";
2002     if (ExtraInfo & InlineAsm::Extra_MayLoad)
2003       OS << " [mayload]";
2004     if (ExtraInfo & InlineAsm::Extra_MayStore)
2005       OS << " [maystore]";
2006     if (ExtraInfo & InlineAsm::Extra_IsConvergent)
2007       OS << " [isconvergent]";
2008     if (ExtraInfo & InlineAsm::Extra_IsAlignStack)
2009       OS << " [alignstack]";
2010     if (getInlineAsmDialect() == InlineAsm::AD_ATT)
2011       OS << " [attdialect]";
2012     if (getInlineAsmDialect() == InlineAsm::AD_Intel)
2013       OS << " [inteldialect]";
2014 
2015     StartOp = AsmDescOp = InlineAsm::MIOp_FirstOperand;
2016     FirstOp = false;
2017   }
2018 
2019   for (unsigned i = StartOp, e = getNumOperands(); i != e; ++i) {
2020     const MachineOperand &MO = getOperand(i);
2021 
2022     if (MO.isReg() && TargetRegisterInfo::isVirtualRegister(MO.getReg()))
2023       VirtRegs.push_back(MO.getReg());
2024 
2025     if (FirstOp) FirstOp = false; else OS << ",";
2026     OS << " ";
2027     if (i < getDesc().NumOperands) {
2028       const MCOperandInfo &MCOI = getDesc().OpInfo[i];
2029       if (MCOI.isPredicate())
2030         OS << "pred:";
2031       if (MCOI.isOptionalDef())
2032         OS << "opt:";
2033     }
2034     if (isDebugValue() && MO.isMetadata()) {
2035       // Pretty print DBG_VALUE instructions.
2036       auto *DIV = dyn_cast<DILocalVariable>(MO.getMetadata());
2037       if (DIV && !DIV->getName().empty())
2038         OS << "!\"" << DIV->getName() << '\"';
2039       else
2040         MO.print(OS, MST, TRI);
2041     } else if (TRI && (isInsertSubreg() || isRegSequence() ||
2042                        (isSubregToReg() && i == 3)) && MO.isImm()) {
2043       OS << TRI->getSubRegIndexName(MO.getImm());
2044     } else if (i == AsmDescOp && MO.isImm()) {
2045       // Pretty print the inline asm operand descriptor.
2046       OS << '$' << AsmOpCount++;
2047       unsigned Flag = MO.getImm();
2048       switch (InlineAsm::getKind(Flag)) {
2049       case InlineAsm::Kind_RegUse:             OS << ":[reguse"; break;
2050       case InlineAsm::Kind_RegDef:             OS << ":[regdef"; break;
2051       case InlineAsm::Kind_RegDefEarlyClobber: OS << ":[regdef-ec"; break;
2052       case InlineAsm::Kind_Clobber:            OS << ":[clobber"; break;
2053       case InlineAsm::Kind_Imm:                OS << ":[imm"; break;
2054       case InlineAsm::Kind_Mem:                OS << ":[mem"; break;
2055       default: OS << ":[??" << InlineAsm::getKind(Flag); break;
2056       }
2057 
2058       unsigned RCID = 0;
2059       if (!InlineAsm::isImmKind(Flag) && !InlineAsm::isMemKind(Flag) &&
2060           InlineAsm::hasRegClassConstraint(Flag, RCID)) {
2061         if (TRI) {
2062           OS << ':' << TRI->getRegClassName(TRI->getRegClass(RCID));
2063         } else
2064           OS << ":RC" << RCID;
2065       }
2066 
2067       if (InlineAsm::isMemKind(Flag)) {
2068         unsigned MCID = InlineAsm::getMemoryConstraintID(Flag);
2069         switch (MCID) {
2070         case InlineAsm::Constraint_es: OS << ":es"; break;
2071         case InlineAsm::Constraint_i:  OS << ":i"; break;
2072         case InlineAsm::Constraint_m:  OS << ":m"; break;
2073         case InlineAsm::Constraint_o:  OS << ":o"; break;
2074         case InlineAsm::Constraint_v:  OS << ":v"; break;
2075         case InlineAsm::Constraint_Q:  OS << ":Q"; break;
2076         case InlineAsm::Constraint_R:  OS << ":R"; break;
2077         case InlineAsm::Constraint_S:  OS << ":S"; break;
2078         case InlineAsm::Constraint_T:  OS << ":T"; break;
2079         case InlineAsm::Constraint_Um: OS << ":Um"; break;
2080         case InlineAsm::Constraint_Un: OS << ":Un"; break;
2081         case InlineAsm::Constraint_Uq: OS << ":Uq"; break;
2082         case InlineAsm::Constraint_Us: OS << ":Us"; break;
2083         case InlineAsm::Constraint_Ut: OS << ":Ut"; break;
2084         case InlineAsm::Constraint_Uv: OS << ":Uv"; break;
2085         case InlineAsm::Constraint_Uy: OS << ":Uy"; break;
2086         case InlineAsm::Constraint_X:  OS << ":X"; break;
2087         case InlineAsm::Constraint_Z:  OS << ":Z"; break;
2088         case InlineAsm::Constraint_ZC: OS << ":ZC"; break;
2089         case InlineAsm::Constraint_Zy: OS << ":Zy"; break;
2090         default: OS << ":?"; break;
2091         }
2092       }
2093 
2094       unsigned TiedTo = 0;
2095       if (InlineAsm::isUseOperandTiedToDef(Flag, TiedTo))
2096         OS << " tiedto:$" << TiedTo;
2097 
2098       OS << ']';
2099 
2100       // Compute the index of the next operand descriptor.
2101       AsmDescOp += 1 + InlineAsm::getNumOperandRegisters(Flag);
2102     } else
2103       MO.print(OS, MST, TRI);
2104   }
2105 
2106   bool HaveSemi = false;
2107   const unsigned PrintableFlags = FrameSetup | FrameDestroy;
2108   if (Flags & PrintableFlags) {
2109     if (!HaveSemi) {
2110       OS << ";";
2111       HaveSemi = true;
2112     }
2113     OS << " flags: ";
2114 
2115     if (Flags & FrameSetup)
2116       OS << "FrameSetup";
2117 
2118     if (Flags & FrameDestroy)
2119       OS << "FrameDestroy";
2120   }
2121 
2122   if (!memoperands_empty()) {
2123     if (!HaveSemi) {
2124       OS << ";";
2125       HaveSemi = true;
2126     }
2127 
2128     OS << " mem:";
2129     for (mmo_iterator i = memoperands_begin(), e = memoperands_end();
2130          i != e; ++i) {
2131       (*i)->print(OS, MST);
2132       if (std::next(i) != e)
2133         OS << " ";
2134     }
2135   }
2136 
2137   // Print the regclass of any virtual registers encountered.
2138   if (MRI && !VirtRegs.empty()) {
2139     if (!HaveSemi) {
2140       OS << ";";
2141       HaveSemi = true;
2142     }
2143     for (unsigned i = 0; i != VirtRegs.size(); ++i) {
2144       const RegClassOrRegBank &RC = MRI->getRegClassOrRegBank(VirtRegs[i]);
2145       if (!RC)
2146         continue;
2147       // Generic virtual registers do not have register classes.
2148       if (RC.is<const RegisterBank *>())
2149         OS << " " << RC.get<const RegisterBank *>()->getName();
2150       else
2151         OS << " "
2152            << TRI->getRegClassName(RC.get<const TargetRegisterClass *>());
2153       OS << ':' << PrintReg(VirtRegs[i]);
2154       for (unsigned j = i+1; j != VirtRegs.size();) {
2155         if (MRI->getRegClassOrRegBank(VirtRegs[j]) != RC) {
2156           ++j;
2157           continue;
2158         }
2159         if (VirtRegs[i] != VirtRegs[j])
2160           OS << "," << PrintReg(VirtRegs[j]);
2161         VirtRegs.erase(VirtRegs.begin()+j);
2162       }
2163     }
2164   }
2165 
2166   // Print debug location information.
2167   if (isDebugValue() && getOperand(e - 2).isMetadata()) {
2168     if (!HaveSemi)
2169       OS << ";";
2170     auto *DV = cast<DILocalVariable>(getOperand(e - 2).getMetadata());
2171     OS << " line no:" <<  DV->getLine();
2172     if (auto *InlinedAt = debugLoc->getInlinedAt()) {
2173       DebugLoc InlinedAtDL(InlinedAt);
2174       if (InlinedAtDL && MF) {
2175         OS << " inlined @[ ";
2176         InlinedAtDL.print(OS);
2177         OS << " ]";
2178       }
2179     }
2180     if (isIndirectDebugValue())
2181       OS << " indirect";
2182   } else if (SkipDebugLoc) {
2183     return;
2184   } else if (debugLoc && MF) {
2185     if (!HaveSemi)
2186       OS << ";";
2187     OS << " dbg:";
2188     debugLoc.print(OS);
2189   }
2190 
2191   OS << '\n';
2192 }
2193 
2194 bool MachineInstr::addRegisterKilled(unsigned IncomingReg,
2195                                      const TargetRegisterInfo *RegInfo,
2196                                      bool AddIfNotFound) {
2197   bool isPhysReg = TargetRegisterInfo::isPhysicalRegister(IncomingReg);
2198   bool hasAliases = isPhysReg &&
2199     MCRegAliasIterator(IncomingReg, RegInfo, false).isValid();
2200   bool Found = false;
2201   SmallVector<unsigned,4> DeadOps;
2202   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
2203     MachineOperand &MO = getOperand(i);
2204     if (!MO.isReg() || !MO.isUse() || MO.isUndef())
2205       continue;
2206 
2207     // DEBUG_VALUE nodes do not contribute to code generation and should
2208     // always be ignored. Failure to do so may result in trying to modify
2209     // KILL flags on DEBUG_VALUE nodes.
2210     if (MO.isDebug())
2211       continue;
2212 
2213     unsigned Reg = MO.getReg();
2214     if (!Reg)
2215       continue;
2216 
2217     if (Reg == IncomingReg) {
2218       if (!Found) {
2219         if (MO.isKill())
2220           // The register is already marked kill.
2221           return true;
2222         if (isPhysReg && isRegTiedToDefOperand(i))
2223           // Two-address uses of physregs must not be marked kill.
2224           return true;
2225         MO.setIsKill();
2226         Found = true;
2227       }
2228     } else if (hasAliases && MO.isKill() &&
2229                TargetRegisterInfo::isPhysicalRegister(Reg)) {
2230       // A super-register kill already exists.
2231       if (RegInfo->isSuperRegister(IncomingReg, Reg))
2232         return true;
2233       if (RegInfo->isSubRegister(IncomingReg, Reg))
2234         DeadOps.push_back(i);
2235     }
2236   }
2237 
2238   // Trim unneeded kill operands.
2239   while (!DeadOps.empty()) {
2240     unsigned OpIdx = DeadOps.back();
2241     if (getOperand(OpIdx).isImplicit())
2242       RemoveOperand(OpIdx);
2243     else
2244       getOperand(OpIdx).setIsKill(false);
2245     DeadOps.pop_back();
2246   }
2247 
2248   // If not found, this means an alias of one of the operands is killed. Add a
2249   // new implicit operand if required.
2250   if (!Found && AddIfNotFound) {
2251     addOperand(MachineOperand::CreateReg(IncomingReg,
2252                                          false /*IsDef*/,
2253                                          true  /*IsImp*/,
2254                                          true  /*IsKill*/));
2255     return true;
2256   }
2257   return Found;
2258 }
2259 
2260 void MachineInstr::clearRegisterKills(unsigned Reg,
2261                                       const TargetRegisterInfo *RegInfo) {
2262   if (!TargetRegisterInfo::isPhysicalRegister(Reg))
2263     RegInfo = nullptr;
2264   for (MachineOperand &MO : operands()) {
2265     if (!MO.isReg() || !MO.isUse() || !MO.isKill())
2266       continue;
2267     unsigned OpReg = MO.getReg();
2268     if ((RegInfo && RegInfo->regsOverlap(Reg, OpReg)) || Reg == OpReg)
2269       MO.setIsKill(false);
2270   }
2271 }
2272 
2273 bool MachineInstr::addRegisterDead(unsigned Reg,
2274                                    const TargetRegisterInfo *RegInfo,
2275                                    bool AddIfNotFound) {
2276   bool isPhysReg = TargetRegisterInfo::isPhysicalRegister(Reg);
2277   bool hasAliases = isPhysReg &&
2278     MCRegAliasIterator(Reg, RegInfo, false).isValid();
2279   bool Found = false;
2280   SmallVector<unsigned,4> DeadOps;
2281   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
2282     MachineOperand &MO = getOperand(i);
2283     if (!MO.isReg() || !MO.isDef())
2284       continue;
2285     unsigned MOReg = MO.getReg();
2286     if (!MOReg)
2287       continue;
2288 
2289     if (MOReg == Reg) {
2290       MO.setIsDead();
2291       Found = true;
2292     } else if (hasAliases && MO.isDead() &&
2293                TargetRegisterInfo::isPhysicalRegister(MOReg)) {
2294       // There exists a super-register that's marked dead.
2295       if (RegInfo->isSuperRegister(Reg, MOReg))
2296         return true;
2297       if (RegInfo->isSubRegister(Reg, MOReg))
2298         DeadOps.push_back(i);
2299     }
2300   }
2301 
2302   // Trim unneeded dead operands.
2303   while (!DeadOps.empty()) {
2304     unsigned OpIdx = DeadOps.back();
2305     if (getOperand(OpIdx).isImplicit())
2306       RemoveOperand(OpIdx);
2307     else
2308       getOperand(OpIdx).setIsDead(false);
2309     DeadOps.pop_back();
2310   }
2311 
2312   // If not found, this means an alias of one of the operands is dead. Add a
2313   // new implicit operand if required.
2314   if (Found || !AddIfNotFound)
2315     return Found;
2316 
2317   addOperand(MachineOperand::CreateReg(Reg,
2318                                        true  /*IsDef*/,
2319                                        true  /*IsImp*/,
2320                                        false /*IsKill*/,
2321                                        true  /*IsDead*/));
2322   return true;
2323 }
2324 
2325 void MachineInstr::clearRegisterDeads(unsigned Reg) {
2326   for (MachineOperand &MO : operands()) {
2327     if (!MO.isReg() || !MO.isDef() || MO.getReg() != Reg)
2328       continue;
2329     MO.setIsDead(false);
2330   }
2331 }
2332 
2333 void MachineInstr::setRegisterDefReadUndef(unsigned Reg, bool IsUndef) {
2334   for (MachineOperand &MO : operands()) {
2335     if (!MO.isReg() || !MO.isDef() || MO.getReg() != Reg || MO.getSubReg() == 0)
2336       continue;
2337     MO.setIsUndef(IsUndef);
2338   }
2339 }
2340 
2341 void MachineInstr::addRegisterDefined(unsigned Reg,
2342                                       const TargetRegisterInfo *RegInfo) {
2343   if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
2344     MachineOperand *MO = findRegisterDefOperand(Reg, false, RegInfo);
2345     if (MO)
2346       return;
2347   } else {
2348     for (const MachineOperand &MO : operands()) {
2349       if (MO.isReg() && MO.getReg() == Reg && MO.isDef() &&
2350           MO.getSubReg() == 0)
2351         return;
2352     }
2353   }
2354   addOperand(MachineOperand::CreateReg(Reg,
2355                                        true  /*IsDef*/,
2356                                        true  /*IsImp*/));
2357 }
2358 
2359 void MachineInstr::setPhysRegsDeadExcept(ArrayRef<unsigned> UsedRegs,
2360                                          const TargetRegisterInfo &TRI) {
2361   bool HasRegMask = false;
2362   for (MachineOperand &MO : operands()) {
2363     if (MO.isRegMask()) {
2364       HasRegMask = true;
2365       continue;
2366     }
2367     if (!MO.isReg() || !MO.isDef()) continue;
2368     unsigned Reg = MO.getReg();
2369     if (!TargetRegisterInfo::isPhysicalRegister(Reg)) continue;
2370     // If there are no uses, including partial uses, the def is dead.
2371     if (llvm::none_of(UsedRegs,
2372                       [&](unsigned Use) { return TRI.regsOverlap(Use, Reg); }))
2373       MO.setIsDead();
2374   }
2375 
2376   // This is a call with a register mask operand.
2377   // Mask clobbers are always dead, so add defs for the non-dead defines.
2378   if (HasRegMask)
2379     for (ArrayRef<unsigned>::iterator I = UsedRegs.begin(), E = UsedRegs.end();
2380          I != E; ++I)
2381       addRegisterDefined(*I, &TRI);
2382 }
2383 
2384 unsigned
2385 MachineInstrExpressionTrait::getHashValue(const MachineInstr* const &MI) {
2386   // Build up a buffer of hash code components.
2387   SmallVector<size_t, 8> HashComponents;
2388   HashComponents.reserve(MI->getNumOperands() + 1);
2389   HashComponents.push_back(MI->getOpcode());
2390   for (const MachineOperand &MO : MI->operands()) {
2391     if (MO.isReg() && MO.isDef() &&
2392         TargetRegisterInfo::isVirtualRegister(MO.getReg()))
2393       continue;  // Skip virtual register defs.
2394 
2395     HashComponents.push_back(hash_value(MO));
2396   }
2397   return hash_combine_range(HashComponents.begin(), HashComponents.end());
2398 }
2399 
2400 void MachineInstr::emitError(StringRef Msg) const {
2401   // Find the source location cookie.
2402   unsigned LocCookie = 0;
2403   const MDNode *LocMD = nullptr;
2404   for (unsigned i = getNumOperands(); i != 0; --i) {
2405     if (getOperand(i-1).isMetadata() &&
2406         (LocMD = getOperand(i-1).getMetadata()) &&
2407         LocMD->getNumOperands() != 0) {
2408       if (const ConstantInt *CI =
2409               mdconst::dyn_extract<ConstantInt>(LocMD->getOperand(0))) {
2410         LocCookie = CI->getZExtValue();
2411         break;
2412       }
2413     }
2414   }
2415 
2416   if (const MachineBasicBlock *MBB = getParent())
2417     if (const MachineFunction *MF = MBB->getParent())
2418       return MF->getMMI().getModule()->getContext().emitError(LocCookie, Msg);
2419   report_fatal_error(Msg);
2420 }
2421 
2422 MachineInstrBuilder llvm::BuildMI(MachineFunction &MF, const DebugLoc &DL,
2423                                   const MCInstrDesc &MCID, bool IsIndirect,
2424                                   unsigned Reg, const MDNode *Variable,
2425                                   const MDNode *Expr) {
2426   assert(isa<DILocalVariable>(Variable) && "not a variable");
2427   assert(cast<DIExpression>(Expr)->isValid() && "not an expression");
2428   assert(cast<DILocalVariable>(Variable)->isValidLocationForIntrinsic(DL) &&
2429          "Expected inlined-at fields to agree");
2430   if (IsIndirect)
2431     return BuildMI(MF, DL, MCID)
2432         .addReg(Reg, RegState::Debug)
2433         .addImm(0U)
2434         .addMetadata(Variable)
2435         .addMetadata(Expr);
2436   else
2437     return BuildMI(MF, DL, MCID)
2438         .addReg(Reg, RegState::Debug)
2439         .addReg(0U, RegState::Debug)
2440         .addMetadata(Variable)
2441         .addMetadata(Expr);
2442 }
2443 
2444 MachineInstrBuilder llvm::BuildMI(MachineBasicBlock &BB,
2445                                   MachineBasicBlock::iterator I,
2446                                   const DebugLoc &DL, const MCInstrDesc &MCID,
2447                                   bool IsIndirect, unsigned Reg,
2448                                   const MDNode *Variable, const MDNode *Expr) {
2449   assert(isa<DILocalVariable>(Variable) && "not a variable");
2450   assert(cast<DIExpression>(Expr)->isValid() && "not an expression");
2451   MachineFunction &MF = *BB.getParent();
2452   MachineInstr *MI = BuildMI(MF, DL, MCID, IsIndirect, Reg, Variable, Expr);
2453   BB.insert(I, MI);
2454   return MachineInstrBuilder(MF, MI);
2455 }
2456 
2457 /// Compute the new DIExpression to use with a DBG_VALUE for a spill slot.
2458 /// This prepends DW_OP_deref when spilling an indirect DBG_VALUE.
2459 static const DIExpression *computeExprForSpill(const MachineInstr &MI) {
2460   assert(MI.getOperand(0).isReg() && "can't spill non-register");
2461   assert(MI.getDebugVariable()->isValidLocationForIntrinsic(MI.getDebugLoc()) &&
2462          "Expected inlined-at fields to agree");
2463 
2464   const DIExpression *Expr = MI.getDebugExpression();
2465   if (MI.isIndirectDebugValue()) {
2466     assert(MI.getOperand(1).getImm() == 0 && "DBG_VALUE with nonzero offset");
2467     Expr = DIExpression::prepend(Expr, DIExpression::WithDeref);
2468   }
2469   return Expr;
2470 }
2471 
2472 MachineInstr *llvm::buildDbgValueForSpill(MachineBasicBlock &BB,
2473                                           MachineBasicBlock::iterator I,
2474                                           const MachineInstr &Orig,
2475                                           int FrameIndex) {
2476   const DIExpression *Expr = computeExprForSpill(Orig);
2477   return BuildMI(BB, I, Orig.getDebugLoc(), Orig.getDesc())
2478       .addFrameIndex(FrameIndex)
2479       .addImm(0U)
2480       .addMetadata(Orig.getDebugVariable())
2481       .addMetadata(Expr);
2482 }
2483 
2484 void llvm::updateDbgValueForSpill(MachineInstr &Orig, int FrameIndex) {
2485   const DIExpression *Expr = computeExprForSpill(Orig);
2486   Orig.getOperand(0).ChangeToFrameIndex(FrameIndex);
2487   Orig.getOperand(1).ChangeToImmediate(0U);
2488   Orig.getOperand(3).setMetadata(Expr);
2489 }
2490