xref: /llvm-project/llvm/lib/CodeGen/MachineInstr.cpp (revision a4989cd603b8e8185e35e3c2b7b48b422d4898be)
1 //===- lib/CodeGen/MachineInstr.cpp ---------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Methods common to all machine instructions.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/CodeGen/MachineInstr.h"
14 #include "llvm/ADT/ArrayRef.h"
15 #include "llvm/ADT/Hashing.h"
16 #include "llvm/ADT/STLExtras.h"
17 #include "llvm/ADT/SmallBitVector.h"
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/Analysis/AliasAnalysis.h"
20 #include "llvm/Analysis/MemoryLocation.h"
21 #include "llvm/CodeGen/MachineBasicBlock.h"
22 #include "llvm/CodeGen/MachineFrameInfo.h"
23 #include "llvm/CodeGen/MachineFunction.h"
24 #include "llvm/CodeGen/MachineInstrBuilder.h"
25 #include "llvm/CodeGen/MachineInstrBundle.h"
26 #include "llvm/CodeGen/MachineMemOperand.h"
27 #include "llvm/CodeGen/MachineModuleInfo.h"
28 #include "llvm/CodeGen/MachineOperand.h"
29 #include "llvm/CodeGen/MachineRegisterInfo.h"
30 #include "llvm/CodeGen/PseudoSourceValue.h"
31 #include "llvm/CodeGen/Register.h"
32 #include "llvm/CodeGen/StackMaps.h"
33 #include "llvm/CodeGen/TargetInstrInfo.h"
34 #include "llvm/CodeGen/TargetRegisterInfo.h"
35 #include "llvm/CodeGen/TargetSubtargetInfo.h"
36 #include "llvm/CodeGenTypes/LowLevelType.h"
37 #include "llvm/IR/Constants.h"
38 #include "llvm/IR/DebugInfoMetadata.h"
39 #include "llvm/IR/DebugLoc.h"
40 #include "llvm/IR/Function.h"
41 #include "llvm/IR/InlineAsm.h"
42 #include "llvm/IR/Instructions.h"
43 #include "llvm/IR/LLVMContext.h"
44 #include "llvm/IR/Metadata.h"
45 #include "llvm/IR/Module.h"
46 #include "llvm/IR/ModuleSlotTracker.h"
47 #include "llvm/IR/Operator.h"
48 #include "llvm/MC/MCInstrDesc.h"
49 #include "llvm/MC/MCRegisterInfo.h"
50 #include "llvm/Support/Casting.h"
51 #include "llvm/Support/Compiler.h"
52 #include "llvm/Support/Debug.h"
53 #include "llvm/Support/ErrorHandling.h"
54 #include "llvm/Support/FormattedStream.h"
55 #include "llvm/Support/raw_ostream.h"
56 #include "llvm/Target/TargetMachine.h"
57 #include <algorithm>
58 #include <cassert>
59 #include <cstdint>
60 #include <cstring>
61 #include <utility>
62 
63 using namespace llvm;
64 
65 static const MachineFunction *getMFIfAvailable(const MachineInstr &MI) {
66   if (const MachineBasicBlock *MBB = MI.getParent())
67     if (const MachineFunction *MF = MBB->getParent())
68       return MF;
69   return nullptr;
70 }
71 
72 // Try to crawl up to the machine function and get TRI and IntrinsicInfo from
73 // it.
74 static void tryToGetTargetInfo(const MachineInstr &MI,
75                                const TargetRegisterInfo *&TRI,
76                                const MachineRegisterInfo *&MRI,
77                                const TargetIntrinsicInfo *&IntrinsicInfo,
78                                const TargetInstrInfo *&TII) {
79 
80   if (const MachineFunction *MF = getMFIfAvailable(MI)) {
81     TRI = MF->getSubtarget().getRegisterInfo();
82     MRI = &MF->getRegInfo();
83     IntrinsicInfo = MF->getTarget().getIntrinsicInfo();
84     TII = MF->getSubtarget().getInstrInfo();
85   }
86 }
87 
88 void MachineInstr::addImplicitDefUseOperands(MachineFunction &MF) {
89   for (MCPhysReg ImpDef : MCID->implicit_defs())
90     addOperand(MF, MachineOperand::CreateReg(ImpDef, true, true));
91   for (MCPhysReg ImpUse : MCID->implicit_uses())
92     addOperand(MF, MachineOperand::CreateReg(ImpUse, false, true));
93 }
94 
95 /// MachineInstr ctor - This constructor creates a MachineInstr and adds the
96 /// implicit operands. It reserves space for the number of operands specified by
97 /// the MCInstrDesc.
98 MachineInstr::MachineInstr(MachineFunction &MF, const MCInstrDesc &TID,
99                            DebugLoc DL, bool NoImp)
100     : MCID(&TID), NumOperands(0), Flags(0), AsmPrinterFlags(0),
101       DbgLoc(std::move(DL)), DebugInstrNum(0), Opcode(TID.Opcode) {
102   assert(DbgLoc.hasTrivialDestructor() && "Expected trivial destructor");
103 
104   // Reserve space for the expected number of operands.
105   if (unsigned NumOps = MCID->getNumOperands() + MCID->implicit_defs().size() +
106                         MCID->implicit_uses().size()) {
107     CapOperands = OperandCapacity::get(NumOps);
108     Operands = MF.allocateOperandArray(CapOperands);
109   }
110 
111   if (!NoImp)
112     addImplicitDefUseOperands(MF);
113 }
114 
115 /// MachineInstr ctor - Copies MachineInstr arg exactly.
116 /// Does not copy the number from debug instruction numbering, to preserve
117 /// uniqueness.
118 MachineInstr::MachineInstr(MachineFunction &MF, const MachineInstr &MI)
119     : MCID(&MI.getDesc()), NumOperands(0), Flags(0), AsmPrinterFlags(0),
120       Info(MI.Info), DbgLoc(MI.getDebugLoc()), DebugInstrNum(0),
121       Opcode(MI.getOpcode()) {
122   assert(DbgLoc.hasTrivialDestructor() && "Expected trivial destructor");
123 
124   CapOperands = OperandCapacity::get(MI.getNumOperands());
125   Operands = MF.allocateOperandArray(CapOperands);
126 
127   // Copy operands.
128   for (const MachineOperand &MO : MI.operands())
129     addOperand(MF, MO);
130 
131   // Replicate ties between the operands, which addOperand was not
132   // able to do reliably.
133   for (unsigned i = 0, e = getNumOperands(); i < e; ++i) {
134     MachineOperand &NewMO = getOperand(i);
135     const MachineOperand &OrigMO = MI.getOperand(i);
136     NewMO.TiedTo = OrigMO.TiedTo;
137   }
138 
139   // Copy all the sensible flags.
140   setFlags(MI.Flags);
141 }
142 
143 void MachineInstr::setDesc(const MCInstrDesc &TID) {
144   if (getParent())
145     getMF()->handleChangeDesc(*this, TID);
146   MCID = &TID;
147   Opcode = TID.Opcode;
148 }
149 
150 void MachineInstr::moveBefore(MachineInstr *MovePos) {
151   MovePos->getParent()->splice(MovePos, getParent(), getIterator());
152 }
153 
154 /// getRegInfo - If this instruction is embedded into a MachineFunction,
155 /// return the MachineRegisterInfo object for the current function, otherwise
156 /// return null.
157 MachineRegisterInfo *MachineInstr::getRegInfo() {
158   if (MachineBasicBlock *MBB = getParent())
159     return &MBB->getParent()->getRegInfo();
160   return nullptr;
161 }
162 
163 const MachineRegisterInfo *MachineInstr::getRegInfo() const {
164   if (const MachineBasicBlock *MBB = getParent())
165     return &MBB->getParent()->getRegInfo();
166   return nullptr;
167 }
168 
169 void MachineInstr::removeRegOperandsFromUseLists(MachineRegisterInfo &MRI) {
170   for (MachineOperand &MO : operands())
171     if (MO.isReg())
172       MRI.removeRegOperandFromUseList(&MO);
173 }
174 
175 void MachineInstr::addRegOperandsToUseLists(MachineRegisterInfo &MRI) {
176   for (MachineOperand &MO : operands())
177     if (MO.isReg())
178       MRI.addRegOperandToUseList(&MO);
179 }
180 
181 void MachineInstr::addOperand(const MachineOperand &Op) {
182   MachineBasicBlock *MBB = getParent();
183   assert(MBB && "Use MachineInstrBuilder to add operands to dangling instrs");
184   MachineFunction *MF = MBB->getParent();
185   assert(MF && "Use MachineInstrBuilder to add operands to dangling instrs");
186   addOperand(*MF, Op);
187 }
188 
189 /// Move NumOps MachineOperands from Src to Dst, with support for overlapping
190 /// ranges. If MRI is non-null also update use-def chains.
191 static void moveOperands(MachineOperand *Dst, MachineOperand *Src,
192                          unsigned NumOps, MachineRegisterInfo *MRI) {
193   if (MRI)
194     return MRI->moveOperands(Dst, Src, NumOps);
195   // MachineOperand is a trivially copyable type so we can just use memmove.
196   assert(Dst && Src && "Unknown operands");
197   std::memmove(Dst, Src, NumOps * sizeof(MachineOperand));
198 }
199 
200 /// addOperand - Add the specified operand to the instruction.  If it is an
201 /// implicit operand, it is added to the end of the operand list.  If it is
202 /// an explicit operand it is added at the end of the explicit operand list
203 /// (before the first implicit operand).
204 void MachineInstr::addOperand(MachineFunction &MF, const MachineOperand &Op) {
205   assert(isUInt<LLVM_MI_NUMOPERANDS_BITS>(NumOperands + 1) &&
206          "Cannot add more operands.");
207   assert(MCID && "Cannot add operands before providing an instr descriptor");
208 
209   // Check if we're adding one of our existing operands.
210   if (&Op >= Operands && &Op < Operands + NumOperands) {
211     // This is unusual: MI->addOperand(MI->getOperand(i)).
212     // If adding Op requires reallocating or moving existing operands around,
213     // the Op reference could go stale. Support it by copying Op.
214     MachineOperand CopyOp(Op);
215     return addOperand(MF, CopyOp);
216   }
217 
218   // Find the insert location for the new operand.  Implicit registers go at
219   // the end, everything else goes before the implicit regs.
220   //
221   // FIXME: Allow mixed explicit and implicit operands on inline asm.
222   // InstrEmitter::EmitSpecialNode() is marking inline asm clobbers as
223   // implicit-defs, but they must not be moved around.  See the FIXME in
224   // InstrEmitter.cpp.
225   unsigned OpNo = getNumOperands();
226   bool isImpReg = Op.isReg() && Op.isImplicit();
227   if (!isImpReg && !isInlineAsm()) {
228     while (OpNo && Operands[OpNo-1].isReg() && Operands[OpNo-1].isImplicit()) {
229       --OpNo;
230       assert(!Operands[OpNo].isTied() && "Cannot move tied operands");
231     }
232   }
233 
234   // OpNo now points as the desired insertion point.  Unless this is a variadic
235   // instruction, only implicit regs are allowed beyond MCID->getNumOperands().
236   // RegMask operands go between the explicit and implicit operands.
237   MachineRegisterInfo *MRI = getRegInfo();
238 
239   // Determine if the Operands array needs to be reallocated.
240   // Save the old capacity and operand array.
241   OperandCapacity OldCap = CapOperands;
242   MachineOperand *OldOperands = Operands;
243   if (!OldOperands || OldCap.getSize() == getNumOperands()) {
244     CapOperands = OldOperands ? OldCap.getNext() : OldCap.get(1);
245     Operands = MF.allocateOperandArray(CapOperands);
246     // Move the operands before the insertion point.
247     if (OpNo)
248       moveOperands(Operands, OldOperands, OpNo, MRI);
249   }
250 
251   // Move the operands following the insertion point.
252   if (OpNo != NumOperands)
253     moveOperands(Operands + OpNo + 1, OldOperands + OpNo, NumOperands - OpNo,
254                  MRI);
255   ++NumOperands;
256 
257   // Deallocate the old operand array.
258   if (OldOperands != Operands && OldOperands)
259     MF.deallocateOperandArray(OldCap, OldOperands);
260 
261   // Copy Op into place. It still needs to be inserted into the MRI use lists.
262   MachineOperand *NewMO = new (Operands + OpNo) MachineOperand(Op);
263   NewMO->ParentMI = this;
264 
265   // When adding a register operand, tell MRI about it.
266   if (NewMO->isReg()) {
267     // Ensure isOnRegUseList() returns false, regardless of Op's status.
268     NewMO->Contents.Reg.Prev = nullptr;
269     // Ignore existing ties. This is not a property that can be copied.
270     NewMO->TiedTo = 0;
271     // Add the new operand to MRI, but only for instructions in an MBB.
272     if (MRI)
273       MRI->addRegOperandToUseList(NewMO);
274     // The MCID operand information isn't accurate until we start adding
275     // explicit operands. The implicit operands are added first, then the
276     // explicits are inserted before them.
277     if (!isImpReg) {
278       // Tie uses to defs as indicated in MCInstrDesc.
279       if (NewMO->isUse()) {
280         int DefIdx = MCID->getOperandConstraint(OpNo, MCOI::TIED_TO);
281         if (DefIdx != -1)
282           tieOperands(DefIdx, OpNo);
283       }
284       // If the register operand is flagged as early, mark the operand as such.
285       if (MCID->getOperandConstraint(OpNo, MCOI::EARLY_CLOBBER) != -1)
286         NewMO->setIsEarlyClobber(true);
287     }
288     // Ensure debug instructions set debug flag on register uses.
289     if (NewMO->isUse() && isDebugInstr())
290       NewMO->setIsDebug();
291   }
292 }
293 
294 void MachineInstr::removeOperand(unsigned OpNo) {
295   assert(OpNo < getNumOperands() && "Invalid operand number");
296   untieRegOperand(OpNo);
297 
298 #ifndef NDEBUG
299   // Moving tied operands would break the ties.
300   for (unsigned i = OpNo + 1, e = getNumOperands(); i != e; ++i)
301     if (Operands[i].isReg())
302       assert(!Operands[i].isTied() && "Cannot move tied operands");
303 #endif
304 
305   MachineRegisterInfo *MRI = getRegInfo();
306   if (MRI && Operands[OpNo].isReg())
307     MRI->removeRegOperandFromUseList(Operands + OpNo);
308 
309   // Don't call the MachineOperand destructor. A lot of this code depends on
310   // MachineOperand having a trivial destructor anyway, and adding a call here
311   // wouldn't make it 'destructor-correct'.
312 
313   if (unsigned N = NumOperands - 1 - OpNo)
314     moveOperands(Operands + OpNo, Operands + OpNo + 1, N, MRI);
315   --NumOperands;
316 }
317 
318 void MachineInstr::setExtraInfo(MachineFunction &MF,
319                                 ArrayRef<MachineMemOperand *> MMOs,
320                                 MCSymbol *PreInstrSymbol,
321                                 MCSymbol *PostInstrSymbol,
322                                 MDNode *HeapAllocMarker, MDNode *PCSections,
323                                 uint32_t CFIType, MDNode *MMRAs) {
324   bool HasPreInstrSymbol = PreInstrSymbol != nullptr;
325   bool HasPostInstrSymbol = PostInstrSymbol != nullptr;
326   bool HasHeapAllocMarker = HeapAllocMarker != nullptr;
327   bool HasPCSections = PCSections != nullptr;
328   bool HasCFIType = CFIType != 0;
329   bool HasMMRAs = MMRAs != nullptr;
330   int NumPointers = MMOs.size() + HasPreInstrSymbol + HasPostInstrSymbol +
331                     HasHeapAllocMarker + HasPCSections + HasCFIType + HasMMRAs;
332 
333   // Drop all extra info if there is none.
334   if (NumPointers <= 0) {
335     Info.clear();
336     return;
337   }
338 
339   // If more than one pointer, then store out of line. Store heap alloc markers
340   // out of line because PointerSumType cannot hold more than 4 tag types with
341   // 32-bit pointers.
342   // FIXME: Maybe we should make the symbols in the extra info mutable?
343   else if (NumPointers > 1 || HasMMRAs || HasHeapAllocMarker || HasPCSections ||
344            HasCFIType) {
345     Info.set<EIIK_OutOfLine>(
346         MF.createMIExtraInfo(MMOs, PreInstrSymbol, PostInstrSymbol,
347                              HeapAllocMarker, PCSections, CFIType, MMRAs));
348     return;
349   }
350 
351   // Otherwise store the single pointer inline.
352   if (HasPreInstrSymbol)
353     Info.set<EIIK_PreInstrSymbol>(PreInstrSymbol);
354   else if (HasPostInstrSymbol)
355     Info.set<EIIK_PostInstrSymbol>(PostInstrSymbol);
356   else
357     Info.set<EIIK_MMO>(MMOs[0]);
358 }
359 
360 void MachineInstr::dropMemRefs(MachineFunction &MF) {
361   if (memoperands_empty())
362     return;
363 
364   setExtraInfo(MF, {}, getPreInstrSymbol(), getPostInstrSymbol(),
365                getHeapAllocMarker(), getPCSections(), getCFIType(),
366                getMMRAMetadata());
367 }
368 
369 void MachineInstr::setMemRefs(MachineFunction &MF,
370                               ArrayRef<MachineMemOperand *> MMOs) {
371   if (MMOs.empty()) {
372     dropMemRefs(MF);
373     return;
374   }
375 
376   setExtraInfo(MF, MMOs, getPreInstrSymbol(), getPostInstrSymbol(),
377                getHeapAllocMarker(), getPCSections(), getCFIType(),
378                getMMRAMetadata());
379 }
380 
381 void MachineInstr::addMemOperand(MachineFunction &MF,
382                                  MachineMemOperand *MO) {
383   SmallVector<MachineMemOperand *, 2> MMOs;
384   MMOs.append(memoperands_begin(), memoperands_end());
385   MMOs.push_back(MO);
386   setMemRefs(MF, MMOs);
387 }
388 
389 void MachineInstr::cloneMemRefs(MachineFunction &MF, const MachineInstr &MI) {
390   if (this == &MI)
391     // Nothing to do for a self-clone!
392     return;
393 
394   assert(&MF == MI.getMF() &&
395          "Invalid machine functions when cloning memory refrences!");
396   // See if we can just steal the extra info already allocated for the
397   // instruction. We can do this whenever the pre- and post-instruction symbols
398   // are the same (including null).
399   if (getPreInstrSymbol() == MI.getPreInstrSymbol() &&
400       getPostInstrSymbol() == MI.getPostInstrSymbol() &&
401       getHeapAllocMarker() == MI.getHeapAllocMarker() &&
402       getPCSections() == MI.getPCSections() && getMMRAMetadata() &&
403       MI.getMMRAMetadata()) {
404     Info = MI.Info;
405     return;
406   }
407 
408   // Otherwise, fall back on a copy-based clone.
409   setMemRefs(MF, MI.memoperands());
410 }
411 
412 /// Check to see if the MMOs pointed to by the two MemRefs arrays are
413 /// identical.
414 static bool hasIdenticalMMOs(ArrayRef<MachineMemOperand *> LHS,
415                              ArrayRef<MachineMemOperand *> RHS) {
416   if (LHS.size() != RHS.size())
417     return false;
418 
419   auto LHSPointees = make_pointee_range(LHS);
420   auto RHSPointees = make_pointee_range(RHS);
421   return std::equal(LHSPointees.begin(), LHSPointees.end(),
422                     RHSPointees.begin());
423 }
424 
425 void MachineInstr::cloneMergedMemRefs(MachineFunction &MF,
426                                       ArrayRef<const MachineInstr *> MIs) {
427   // Try handling easy numbers of MIs with simpler mechanisms.
428   if (MIs.empty()) {
429     dropMemRefs(MF);
430     return;
431   }
432   if (MIs.size() == 1) {
433     cloneMemRefs(MF, *MIs[0]);
434     return;
435   }
436   // Because an empty memoperands list provides *no* information and must be
437   // handled conservatively (assuming the instruction can do anything), the only
438   // way to merge with it is to drop all other memoperands.
439   if (MIs[0]->memoperands_empty()) {
440     dropMemRefs(MF);
441     return;
442   }
443 
444   // Handle the general case.
445   SmallVector<MachineMemOperand *, 2> MergedMMOs;
446   // Start with the first instruction.
447   assert(&MF == MIs[0]->getMF() &&
448          "Invalid machine functions when cloning memory references!");
449   MergedMMOs.append(MIs[0]->memoperands_begin(), MIs[0]->memoperands_end());
450   // Now walk all the other instructions and accumulate any different MMOs.
451   for (const MachineInstr &MI : make_pointee_range(MIs.slice(1))) {
452     assert(&MF == MI.getMF() &&
453            "Invalid machine functions when cloning memory references!");
454 
455     // Skip MIs with identical operands to the first. This is a somewhat
456     // arbitrary hack but will catch common cases without being quadratic.
457     // TODO: We could fully implement merge semantics here if needed.
458     if (hasIdenticalMMOs(MIs[0]->memoperands(), MI.memoperands()))
459       continue;
460 
461     // Because an empty memoperands list provides *no* information and must be
462     // handled conservatively (assuming the instruction can do anything), the
463     // only way to merge with it is to drop all other memoperands.
464     if (MI.memoperands_empty()) {
465       dropMemRefs(MF);
466       return;
467     }
468 
469     // Otherwise accumulate these into our temporary buffer of the merged state.
470     MergedMMOs.append(MI.memoperands_begin(), MI.memoperands_end());
471   }
472 
473   setMemRefs(MF, MergedMMOs);
474 }
475 
476 void MachineInstr::setPreInstrSymbol(MachineFunction &MF, MCSymbol *Symbol) {
477   // Do nothing if old and new symbols are the same.
478   if (Symbol == getPreInstrSymbol())
479     return;
480 
481   // If there was only one symbol and we're removing it, just clear info.
482   if (!Symbol && Info.is<EIIK_PreInstrSymbol>()) {
483     Info.clear();
484     return;
485   }
486 
487   setExtraInfo(MF, memoperands(), Symbol, getPostInstrSymbol(),
488                getHeapAllocMarker(), getPCSections(), getCFIType(),
489                getMMRAMetadata());
490 }
491 
492 void MachineInstr::setPostInstrSymbol(MachineFunction &MF, MCSymbol *Symbol) {
493   // Do nothing if old and new symbols are the same.
494   if (Symbol == getPostInstrSymbol())
495     return;
496 
497   // If there was only one symbol and we're removing it, just clear info.
498   if (!Symbol && Info.is<EIIK_PostInstrSymbol>()) {
499     Info.clear();
500     return;
501   }
502 
503   setExtraInfo(MF, memoperands(), getPreInstrSymbol(), Symbol,
504                getHeapAllocMarker(), getPCSections(), getCFIType(),
505                getMMRAMetadata());
506 }
507 
508 void MachineInstr::setHeapAllocMarker(MachineFunction &MF, MDNode *Marker) {
509   // Do nothing if old and new symbols are the same.
510   if (Marker == getHeapAllocMarker())
511     return;
512 
513   setExtraInfo(MF, memoperands(), getPreInstrSymbol(), getPostInstrSymbol(),
514                Marker, getPCSections(), getCFIType(), getMMRAMetadata());
515 }
516 
517 void MachineInstr::setPCSections(MachineFunction &MF, MDNode *PCSections) {
518   // Do nothing if old and new symbols are the same.
519   if (PCSections == getPCSections())
520     return;
521 
522   setExtraInfo(MF, memoperands(), getPreInstrSymbol(), getPostInstrSymbol(),
523                getHeapAllocMarker(), PCSections, getCFIType(),
524                getMMRAMetadata());
525 }
526 
527 void MachineInstr::setCFIType(MachineFunction &MF, uint32_t Type) {
528   // Do nothing if old and new types are the same.
529   if (Type == getCFIType())
530     return;
531 
532   setExtraInfo(MF, memoperands(), getPreInstrSymbol(), getPostInstrSymbol(),
533                getHeapAllocMarker(), getPCSections(), Type, getMMRAMetadata());
534 }
535 
536 void MachineInstr::setMMRAMetadata(MachineFunction &MF, MDNode *MMRAs) {
537   // Do nothing if old and new symbols are the same.
538   if (MMRAs == getMMRAMetadata())
539     return;
540 
541   setExtraInfo(MF, memoperands(), getPreInstrSymbol(), getPostInstrSymbol(),
542                getHeapAllocMarker(), getPCSections(), getCFIType(), MMRAs);
543 }
544 
545 void MachineInstr::cloneInstrSymbols(MachineFunction &MF,
546                                      const MachineInstr &MI) {
547   if (this == &MI)
548     // Nothing to do for a self-clone!
549     return;
550 
551   assert(&MF == MI.getMF() &&
552          "Invalid machine functions when cloning instruction symbols!");
553 
554   setPreInstrSymbol(MF, MI.getPreInstrSymbol());
555   setPostInstrSymbol(MF, MI.getPostInstrSymbol());
556   setHeapAllocMarker(MF, MI.getHeapAllocMarker());
557   setPCSections(MF, MI.getPCSections());
558   setMMRAMetadata(MF, MI.getMMRAMetadata());
559 }
560 
561 uint32_t MachineInstr::mergeFlagsWith(const MachineInstr &Other) const {
562   // For now, the just return the union of the flags. If the flags get more
563   // complicated over time, we might need more logic here.
564   return getFlags() | Other.getFlags();
565 }
566 
567 uint32_t MachineInstr::copyFlagsFromInstruction(const Instruction &I) {
568   uint32_t MIFlags = 0;
569   // Copy the wrapping flags.
570   if (const OverflowingBinaryOperator *OB =
571           dyn_cast<OverflowingBinaryOperator>(&I)) {
572     if (OB->hasNoSignedWrap())
573       MIFlags |= MachineInstr::MIFlag::NoSWrap;
574     if (OB->hasNoUnsignedWrap())
575       MIFlags |= MachineInstr::MIFlag::NoUWrap;
576   } else if (const TruncInst *TI = dyn_cast<TruncInst>(&I)) {
577     if (TI->hasNoSignedWrap())
578       MIFlags |= MachineInstr::MIFlag::NoSWrap;
579     if (TI->hasNoUnsignedWrap())
580       MIFlags |= MachineInstr::MIFlag::NoUWrap;
581   } else if (const GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(&I)) {
582     if (GEP->hasNoUnsignedSignedWrap())
583       MIFlags |= MachineInstr::MIFlag::NoUSWrap;
584     if (GEP->hasNoUnsignedWrap())
585       MIFlags |= MachineInstr::MIFlag::NoUWrap;
586   }
587 
588   // Copy the nonneg flag.
589   if (const PossiblyNonNegInst *PNI = dyn_cast<PossiblyNonNegInst>(&I)) {
590     if (PNI->hasNonNeg())
591       MIFlags |= MachineInstr::MIFlag::NonNeg;
592     // Copy the disjoint flag.
593   } else if (const PossiblyDisjointInst *PD =
594                  dyn_cast<PossiblyDisjointInst>(&I)) {
595     if (PD->isDisjoint())
596       MIFlags |= MachineInstr::MIFlag::Disjoint;
597   }
598 
599   // Copy the exact flag.
600   if (const PossiblyExactOperator *PE = dyn_cast<PossiblyExactOperator>(&I))
601     if (PE->isExact())
602       MIFlags |= MachineInstr::MIFlag::IsExact;
603 
604   // Copy the fast-math flags.
605   if (const FPMathOperator *FP = dyn_cast<FPMathOperator>(&I)) {
606     const FastMathFlags Flags = FP->getFastMathFlags();
607     if (Flags.noNaNs())
608       MIFlags |= MachineInstr::MIFlag::FmNoNans;
609     if (Flags.noInfs())
610       MIFlags |= MachineInstr::MIFlag::FmNoInfs;
611     if (Flags.noSignedZeros())
612       MIFlags |= MachineInstr::MIFlag::FmNsz;
613     if (Flags.allowReciprocal())
614       MIFlags |= MachineInstr::MIFlag::FmArcp;
615     if (Flags.allowContract())
616       MIFlags |= MachineInstr::MIFlag::FmContract;
617     if (Flags.approxFunc())
618       MIFlags |= MachineInstr::MIFlag::FmAfn;
619     if (Flags.allowReassoc())
620       MIFlags |= MachineInstr::MIFlag::FmReassoc;
621   }
622 
623   if (I.getMetadata(LLVMContext::MD_unpredictable))
624     MIFlags |= MachineInstr::MIFlag::Unpredictable;
625 
626   return MIFlags;
627 }
628 
629 void MachineInstr::copyIRFlags(const Instruction &I) {
630   Flags = copyFlagsFromInstruction(I);
631 }
632 
633 bool MachineInstr::hasPropertyInBundle(uint64_t Mask, QueryType Type) const {
634   assert(!isBundledWithPred() && "Must be called on bundle header");
635   for (MachineBasicBlock::const_instr_iterator MII = getIterator();; ++MII) {
636     if (MII->getDesc().getFlags() & Mask) {
637       if (Type == AnyInBundle)
638         return true;
639     } else {
640       if (Type == AllInBundle && !MII->isBundle())
641         return false;
642     }
643     // This was the last instruction in the bundle.
644     if (!MII->isBundledWithSucc())
645       return Type == AllInBundle;
646   }
647 }
648 
649 bool MachineInstr::isIdenticalTo(const MachineInstr &Other,
650                                  MICheckType Check) const {
651   // If opcodes or number of operands are not the same then the two
652   // instructions are obviously not identical.
653   if (Other.getOpcode() != getOpcode() ||
654       Other.getNumOperands() != getNumOperands())
655     return false;
656 
657   if (isBundle()) {
658     // We have passed the test above that both instructions have the same
659     // opcode, so we know that both instructions are bundles here. Let's compare
660     // MIs inside the bundle.
661     assert(Other.isBundle() && "Expected that both instructions are bundles.");
662     MachineBasicBlock::const_instr_iterator I1 = getIterator();
663     MachineBasicBlock::const_instr_iterator I2 = Other.getIterator();
664     // Loop until we analysed the last intruction inside at least one of the
665     // bundles.
666     while (I1->isBundledWithSucc() && I2->isBundledWithSucc()) {
667       ++I1;
668       ++I2;
669       if (!I1->isIdenticalTo(*I2, Check))
670         return false;
671     }
672     // If we've reached the end of just one of the two bundles, but not both,
673     // the instructions are not identical.
674     if (I1->isBundledWithSucc() || I2->isBundledWithSucc())
675       return false;
676   }
677 
678   // Check operands to make sure they match.
679   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
680     const MachineOperand &MO = getOperand(i);
681     const MachineOperand &OMO = Other.getOperand(i);
682     if (!MO.isReg()) {
683       if (!MO.isIdenticalTo(OMO))
684         return false;
685       continue;
686     }
687 
688     // Clients may or may not want to ignore defs when testing for equality.
689     // For example, machine CSE pass only cares about finding common
690     // subexpressions, so it's safe to ignore virtual register defs.
691     if (MO.isDef()) {
692       if (Check == IgnoreDefs)
693         continue;
694       else if (Check == IgnoreVRegDefs) {
695         if (!MO.getReg().isVirtual() || !OMO.getReg().isVirtual())
696           if (!MO.isIdenticalTo(OMO))
697             return false;
698       } else {
699         if (!MO.isIdenticalTo(OMO))
700           return false;
701         if (Check == CheckKillDead && MO.isDead() != OMO.isDead())
702           return false;
703       }
704     } else {
705       if (!MO.isIdenticalTo(OMO))
706         return false;
707       if (Check == CheckKillDead && MO.isKill() != OMO.isKill())
708         return false;
709     }
710   }
711   // If DebugLoc does not match then two debug instructions are not identical.
712   if (isDebugInstr())
713     if (getDebugLoc() && Other.getDebugLoc() &&
714         getDebugLoc() != Other.getDebugLoc())
715       return false;
716   // If pre- or post-instruction symbols do not match then the two instructions
717   // are not identical.
718   if (getPreInstrSymbol() != Other.getPreInstrSymbol() ||
719       getPostInstrSymbol() != Other.getPostInstrSymbol())
720     return false;
721   // Call instructions with different CFI types are not identical.
722   if (isCall() && getCFIType() != Other.getCFIType())
723     return false;
724 
725   return true;
726 }
727 
728 bool MachineInstr::isEquivalentDbgInstr(const MachineInstr &Other) const {
729   if (!isDebugValueLike() || !Other.isDebugValueLike())
730     return false;
731   if (getDebugLoc() != Other.getDebugLoc())
732     return false;
733   if (getDebugVariable() != Other.getDebugVariable())
734     return false;
735   if (getNumDebugOperands() != Other.getNumDebugOperands())
736     return false;
737   for (unsigned OpIdx = 0; OpIdx < getNumDebugOperands(); ++OpIdx)
738     if (!getDebugOperand(OpIdx).isIdenticalTo(Other.getDebugOperand(OpIdx)))
739       return false;
740   if (!DIExpression::isEqualExpression(
741           getDebugExpression(), isIndirectDebugValue(),
742           Other.getDebugExpression(), Other.isIndirectDebugValue()))
743     return false;
744   return true;
745 }
746 
747 const MachineFunction *MachineInstr::getMF() const {
748   return getParent()->getParent();
749 }
750 
751 MachineInstr *MachineInstr::removeFromParent() {
752   assert(getParent() && "Not embedded in a basic block!");
753   return getParent()->remove(this);
754 }
755 
756 MachineInstr *MachineInstr::removeFromBundle() {
757   assert(getParent() && "Not embedded in a basic block!");
758   return getParent()->remove_instr(this);
759 }
760 
761 void MachineInstr::eraseFromParent() {
762   assert(getParent() && "Not embedded in a basic block!");
763   getParent()->erase(this);
764 }
765 
766 void MachineInstr::eraseFromBundle() {
767   assert(getParent() && "Not embedded in a basic block!");
768   getParent()->erase_instr(this);
769 }
770 
771 bool MachineInstr::isCandidateForCallSiteEntry(QueryType Type) const {
772   if (!isCall(Type))
773     return false;
774   switch (getOpcode()) {
775   case TargetOpcode::PATCHPOINT:
776   case TargetOpcode::STACKMAP:
777   case TargetOpcode::STATEPOINT:
778   case TargetOpcode::FENTRY_CALL:
779     return false;
780   }
781   return true;
782 }
783 
784 bool MachineInstr::shouldUpdateCallSiteInfo() const {
785   if (isBundle())
786     return isCandidateForCallSiteEntry(MachineInstr::AnyInBundle);
787   return isCandidateForCallSiteEntry();
788 }
789 
790 unsigned MachineInstr::getNumExplicitOperands() const {
791   unsigned NumOperands = MCID->getNumOperands();
792   if (!MCID->isVariadic())
793     return NumOperands;
794 
795   for (unsigned I = NumOperands, E = getNumOperands(); I != E; ++I) {
796     const MachineOperand &MO = getOperand(I);
797     // The operands must always be in the following order:
798     // - explicit reg defs,
799     // - other explicit operands (reg uses, immediates, etc.),
800     // - implicit reg defs
801     // - implicit reg uses
802     if (MO.isReg() && MO.isImplicit())
803       break;
804     ++NumOperands;
805   }
806   return NumOperands;
807 }
808 
809 unsigned MachineInstr::getNumExplicitDefs() const {
810   unsigned NumDefs = MCID->getNumDefs();
811   if (!MCID->isVariadic())
812     return NumDefs;
813 
814   for (unsigned I = NumDefs, E = getNumOperands(); I != E; ++I) {
815     const MachineOperand &MO = getOperand(I);
816     if (!MO.isReg() || !MO.isDef() || MO.isImplicit())
817       break;
818     ++NumDefs;
819   }
820   return NumDefs;
821 }
822 
823 void MachineInstr::bundleWithPred() {
824   assert(!isBundledWithPred() && "MI is already bundled with its predecessor");
825   setFlag(BundledPred);
826   MachineBasicBlock::instr_iterator Pred = getIterator();
827   --Pred;
828   assert(!Pred->isBundledWithSucc() && "Inconsistent bundle flags");
829   Pred->setFlag(BundledSucc);
830 }
831 
832 void MachineInstr::bundleWithSucc() {
833   assert(!isBundledWithSucc() && "MI is already bundled with its successor");
834   setFlag(BundledSucc);
835   MachineBasicBlock::instr_iterator Succ = getIterator();
836   ++Succ;
837   assert(!Succ->isBundledWithPred() && "Inconsistent bundle flags");
838   Succ->setFlag(BundledPred);
839 }
840 
841 void MachineInstr::unbundleFromPred() {
842   assert(isBundledWithPred() && "MI isn't bundled with its predecessor");
843   clearFlag(BundledPred);
844   MachineBasicBlock::instr_iterator Pred = getIterator();
845   --Pred;
846   assert(Pred->isBundledWithSucc() && "Inconsistent bundle flags");
847   Pred->clearFlag(BundledSucc);
848 }
849 
850 void MachineInstr::unbundleFromSucc() {
851   assert(isBundledWithSucc() && "MI isn't bundled with its successor");
852   clearFlag(BundledSucc);
853   MachineBasicBlock::instr_iterator Succ = getIterator();
854   ++Succ;
855   assert(Succ->isBundledWithPred() && "Inconsistent bundle flags");
856   Succ->clearFlag(BundledPred);
857 }
858 
859 bool MachineInstr::isStackAligningInlineAsm() const {
860   if (isInlineAsm()) {
861     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
862     if (ExtraInfo & InlineAsm::Extra_IsAlignStack)
863       return true;
864   }
865   return false;
866 }
867 
868 InlineAsm::AsmDialect MachineInstr::getInlineAsmDialect() const {
869   assert(isInlineAsm() && "getInlineAsmDialect() only works for inline asms!");
870   unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
871   return InlineAsm::AsmDialect((ExtraInfo & InlineAsm::Extra_AsmDialect) != 0);
872 }
873 
874 int MachineInstr::findInlineAsmFlagIdx(unsigned OpIdx,
875                                        unsigned *GroupNo) const {
876   assert(isInlineAsm() && "Expected an inline asm instruction");
877   assert(OpIdx < getNumOperands() && "OpIdx out of range");
878 
879   // Ignore queries about the initial operands.
880   if (OpIdx < InlineAsm::MIOp_FirstOperand)
881     return -1;
882 
883   unsigned Group = 0;
884   unsigned NumOps;
885   for (unsigned i = InlineAsm::MIOp_FirstOperand, e = getNumOperands(); i < e;
886        i += NumOps) {
887     const MachineOperand &FlagMO = getOperand(i);
888     // If we reach the implicit register operands, stop looking.
889     if (!FlagMO.isImm())
890       return -1;
891     const InlineAsm::Flag F(FlagMO.getImm());
892     NumOps = 1 + F.getNumOperandRegisters();
893     if (i + NumOps > OpIdx) {
894       if (GroupNo)
895         *GroupNo = Group;
896       return i;
897     }
898     ++Group;
899   }
900   return -1;
901 }
902 
903 const DILabel *MachineInstr::getDebugLabel() const {
904   assert(isDebugLabel() && "not a DBG_LABEL");
905   return cast<DILabel>(getOperand(0).getMetadata());
906 }
907 
908 const MachineOperand &MachineInstr::getDebugVariableOp() const {
909   assert((isDebugValueLike()) && "not a DBG_VALUE*");
910   unsigned VariableOp = isNonListDebugValue() ? 2 : 0;
911   return getOperand(VariableOp);
912 }
913 
914 MachineOperand &MachineInstr::getDebugVariableOp() {
915   assert((isDebugValueLike()) && "not a DBG_VALUE*");
916   unsigned VariableOp = isNonListDebugValue() ? 2 : 0;
917   return getOperand(VariableOp);
918 }
919 
920 const DILocalVariable *MachineInstr::getDebugVariable() const {
921   return cast<DILocalVariable>(getDebugVariableOp().getMetadata());
922 }
923 
924 const MachineOperand &MachineInstr::getDebugExpressionOp() const {
925   assert((isDebugValueLike()) && "not a DBG_VALUE*");
926   unsigned ExpressionOp = isNonListDebugValue() ? 3 : 1;
927   return getOperand(ExpressionOp);
928 }
929 
930 MachineOperand &MachineInstr::getDebugExpressionOp() {
931   assert((isDebugValueLike()) && "not a DBG_VALUE*");
932   unsigned ExpressionOp = isNonListDebugValue() ? 3 : 1;
933   return getOperand(ExpressionOp);
934 }
935 
936 const DIExpression *MachineInstr::getDebugExpression() const {
937   return cast<DIExpression>(getDebugExpressionOp().getMetadata());
938 }
939 
940 bool MachineInstr::isDebugEntryValue() const {
941   return isDebugValue() && getDebugExpression()->isEntryValue();
942 }
943 
944 const TargetRegisterClass*
945 MachineInstr::getRegClassConstraint(unsigned OpIdx,
946                                     const TargetInstrInfo *TII,
947                                     const TargetRegisterInfo *TRI) const {
948   assert(getParent() && "Can't have an MBB reference here!");
949   assert(getMF() && "Can't have an MF reference here!");
950   const MachineFunction &MF = *getMF();
951 
952   // Most opcodes have fixed constraints in their MCInstrDesc.
953   if (!isInlineAsm())
954     return TII->getRegClass(getDesc(), OpIdx, TRI, MF);
955 
956   if (!getOperand(OpIdx).isReg())
957     return nullptr;
958 
959   // For tied uses on inline asm, get the constraint from the def.
960   unsigned DefIdx;
961   if (getOperand(OpIdx).isUse() && isRegTiedToDefOperand(OpIdx, &DefIdx))
962     OpIdx = DefIdx;
963 
964   // Inline asm stores register class constraints in the flag word.
965   int FlagIdx = findInlineAsmFlagIdx(OpIdx);
966   if (FlagIdx < 0)
967     return nullptr;
968 
969   const InlineAsm::Flag F(getOperand(FlagIdx).getImm());
970   unsigned RCID;
971   if ((F.isRegUseKind() || F.isRegDefKind() || F.isRegDefEarlyClobberKind()) &&
972       F.hasRegClassConstraint(RCID))
973     return TRI->getRegClass(RCID);
974 
975   // Assume that all registers in a memory operand are pointers.
976   if (F.isMemKind())
977     return TRI->getPointerRegClass(MF);
978 
979   return nullptr;
980 }
981 
982 const TargetRegisterClass *MachineInstr::getRegClassConstraintEffectForVReg(
983     Register Reg, const TargetRegisterClass *CurRC, const TargetInstrInfo *TII,
984     const TargetRegisterInfo *TRI, bool ExploreBundle) const {
985   // Check every operands inside the bundle if we have
986   // been asked to.
987   if (ExploreBundle)
988     for (ConstMIBundleOperands OpndIt(*this); OpndIt.isValid() && CurRC;
989          ++OpndIt)
990       CurRC = OpndIt->getParent()->getRegClassConstraintEffectForVRegImpl(
991           OpndIt.getOperandNo(), Reg, CurRC, TII, TRI);
992   else
993     // Otherwise, just check the current operands.
994     for (unsigned i = 0, e = NumOperands; i < e && CurRC; ++i)
995       CurRC = getRegClassConstraintEffectForVRegImpl(i, Reg, CurRC, TII, TRI);
996   return CurRC;
997 }
998 
999 const TargetRegisterClass *MachineInstr::getRegClassConstraintEffectForVRegImpl(
1000     unsigned OpIdx, Register Reg, const TargetRegisterClass *CurRC,
1001     const TargetInstrInfo *TII, const TargetRegisterInfo *TRI) const {
1002   assert(CurRC && "Invalid initial register class");
1003   // Check if Reg is constrained by some of its use/def from MI.
1004   const MachineOperand &MO = getOperand(OpIdx);
1005   if (!MO.isReg() || MO.getReg() != Reg)
1006     return CurRC;
1007   // If yes, accumulate the constraints through the operand.
1008   return getRegClassConstraintEffect(OpIdx, CurRC, TII, TRI);
1009 }
1010 
1011 const TargetRegisterClass *MachineInstr::getRegClassConstraintEffect(
1012     unsigned OpIdx, const TargetRegisterClass *CurRC,
1013     const TargetInstrInfo *TII, const TargetRegisterInfo *TRI) const {
1014   const TargetRegisterClass *OpRC = getRegClassConstraint(OpIdx, TII, TRI);
1015   const MachineOperand &MO = getOperand(OpIdx);
1016   assert(MO.isReg() &&
1017          "Cannot get register constraints for non-register operand");
1018   assert(CurRC && "Invalid initial register class");
1019   if (unsigned SubIdx = MO.getSubReg()) {
1020     if (OpRC)
1021       CurRC = TRI->getMatchingSuperRegClass(CurRC, OpRC, SubIdx);
1022     else
1023       CurRC = TRI->getSubClassWithSubReg(CurRC, SubIdx);
1024   } else if (OpRC)
1025     CurRC = TRI->getCommonSubClass(CurRC, OpRC);
1026   return CurRC;
1027 }
1028 
1029 /// Return the number of instructions inside the MI bundle, not counting the
1030 /// header instruction.
1031 unsigned MachineInstr::getBundleSize() const {
1032   MachineBasicBlock::const_instr_iterator I = getIterator();
1033   unsigned Size = 0;
1034   while (I->isBundledWithSucc()) {
1035     ++Size;
1036     ++I;
1037   }
1038   return Size;
1039 }
1040 
1041 /// Returns true if the MachineInstr has an implicit-use operand of exactly
1042 /// the given register (not considering sub/super-registers).
1043 bool MachineInstr::hasRegisterImplicitUseOperand(Register Reg) const {
1044   for (const MachineOperand &MO : all_uses())
1045     if (MO.isImplicit() && MO.getReg() == Reg)
1046       return true;
1047   return false;
1048 }
1049 
1050 /// findRegisterUseOperandIdx() - Returns the MachineOperand that is a use of
1051 /// the specific register or -1 if it is not found. It further tightens
1052 /// the search criteria to a use that kills the register if isKill is true.
1053 int MachineInstr::findRegisterUseOperandIdx(Register Reg,
1054                                             const TargetRegisterInfo *TRI,
1055                                             bool isKill) const {
1056   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1057     const MachineOperand &MO = getOperand(i);
1058     if (!MO.isReg() || !MO.isUse())
1059       continue;
1060     Register MOReg = MO.getReg();
1061     if (!MOReg)
1062       continue;
1063     if (MOReg == Reg || (TRI && Reg && MOReg && TRI->regsOverlap(MOReg, Reg)))
1064       if (!isKill || MO.isKill())
1065         return i;
1066   }
1067   return -1;
1068 }
1069 
1070 /// readsWritesVirtualRegister - Return a pair of bools (reads, writes)
1071 /// indicating if this instruction reads or writes Reg. This also considers
1072 /// partial defines.
1073 std::pair<bool,bool>
1074 MachineInstr::readsWritesVirtualRegister(Register Reg,
1075                                          SmallVectorImpl<unsigned> *Ops) const {
1076   bool PartDef = false; // Partial redefine.
1077   bool FullDef = false; // Full define.
1078   bool Use = false;
1079 
1080   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1081     const MachineOperand &MO = getOperand(i);
1082     if (!MO.isReg() || MO.getReg() != Reg)
1083       continue;
1084     if (Ops)
1085       Ops->push_back(i);
1086     if (MO.isUse())
1087       Use |= !MO.isUndef();
1088     else if (MO.getSubReg() && !MO.isUndef())
1089       // A partial def undef doesn't count as reading the register.
1090       PartDef = true;
1091     else
1092       FullDef = true;
1093   }
1094   // A partial redefine uses Reg unless there is also a full define.
1095   return std::make_pair(Use || (PartDef && !FullDef), PartDef || FullDef);
1096 }
1097 
1098 /// findRegisterDefOperandIdx() - Returns the operand index that is a def of
1099 /// the specified register or -1 if it is not found. If isDead is true, defs
1100 /// that are not dead are skipped. If TargetRegisterInfo is non-null, then it
1101 /// also checks if there is a def of a super-register.
1102 int MachineInstr::findRegisterDefOperandIdx(Register Reg,
1103                                             const TargetRegisterInfo *TRI,
1104                                             bool isDead, bool Overlap) const {
1105   bool isPhys = Reg.isPhysical();
1106   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1107     const MachineOperand &MO = getOperand(i);
1108     // Accept regmask operands when Overlap is set.
1109     // Ignore them when looking for a specific def operand (Overlap == false).
1110     if (isPhys && Overlap && MO.isRegMask() && MO.clobbersPhysReg(Reg))
1111       return i;
1112     if (!MO.isReg() || !MO.isDef())
1113       continue;
1114     Register MOReg = MO.getReg();
1115     bool Found = (MOReg == Reg);
1116     if (!Found && TRI && isPhys && MOReg.isPhysical()) {
1117       if (Overlap)
1118         Found = TRI->regsOverlap(MOReg, Reg);
1119       else
1120         Found = TRI->isSubRegister(MOReg, Reg);
1121     }
1122     if (Found && (!isDead || MO.isDead()))
1123       return i;
1124   }
1125   return -1;
1126 }
1127 
1128 /// findFirstPredOperandIdx() - Find the index of the first operand in the
1129 /// operand list that is used to represent the predicate. It returns -1 if
1130 /// none is found.
1131 int MachineInstr::findFirstPredOperandIdx() const {
1132   // Don't call MCID.findFirstPredOperandIdx() because this variant
1133   // is sometimes called on an instruction that's not yet complete, and
1134   // so the number of operands is less than the MCID indicates. In
1135   // particular, the PTX target does this.
1136   const MCInstrDesc &MCID = getDesc();
1137   if (MCID.isPredicable()) {
1138     for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
1139       if (MCID.operands()[i].isPredicate())
1140         return i;
1141   }
1142 
1143   return -1;
1144 }
1145 
1146 // MachineOperand::TiedTo is 4 bits wide.
1147 const unsigned TiedMax = 15;
1148 
1149 /// tieOperands - Mark operands at DefIdx and UseIdx as tied to each other.
1150 ///
1151 /// Use and def operands can be tied together, indicated by a non-zero TiedTo
1152 /// field. TiedTo can have these values:
1153 ///
1154 /// 0:              Operand is not tied to anything.
1155 /// 1 to TiedMax-1: Tied to getOperand(TiedTo-1).
1156 /// TiedMax:        Tied to an operand >= TiedMax-1.
1157 ///
1158 /// The tied def must be one of the first TiedMax operands on a normal
1159 /// instruction. INLINEASM instructions allow more tied defs.
1160 ///
1161 void MachineInstr::tieOperands(unsigned DefIdx, unsigned UseIdx) {
1162   MachineOperand &DefMO = getOperand(DefIdx);
1163   MachineOperand &UseMO = getOperand(UseIdx);
1164   assert(DefMO.isDef() && "DefIdx must be a def operand");
1165   assert(UseMO.isUse() && "UseIdx must be a use operand");
1166   assert(!DefMO.isTied() && "Def is already tied to another use");
1167   assert(!UseMO.isTied() && "Use is already tied to another def");
1168 
1169   if (DefIdx < TiedMax)
1170     UseMO.TiedTo = DefIdx + 1;
1171   else {
1172     // Inline asm can use the group descriptors to find tied operands,
1173     // statepoint tied operands are trivial to match (1-1 reg def with reg use),
1174     // but on normal instruction, the tied def must be within the first TiedMax
1175     // operands.
1176     assert((isInlineAsm() || getOpcode() == TargetOpcode::STATEPOINT) &&
1177            "DefIdx out of range");
1178     UseMO.TiedTo = TiedMax;
1179   }
1180 
1181   // UseIdx can be out of range, we'll search for it in findTiedOperandIdx().
1182   DefMO.TiedTo = std::min(UseIdx + 1, TiedMax);
1183 }
1184 
1185 /// Given the index of a tied register operand, find the operand it is tied to.
1186 /// Defs are tied to uses and vice versa. Returns the index of the tied operand
1187 /// which must exist.
1188 unsigned MachineInstr::findTiedOperandIdx(unsigned OpIdx) const {
1189   const MachineOperand &MO = getOperand(OpIdx);
1190   assert(MO.isTied() && "Operand isn't tied");
1191 
1192   // Normally TiedTo is in range.
1193   if (MO.TiedTo < TiedMax)
1194     return MO.TiedTo - 1;
1195 
1196   // Uses on normal instructions can be out of range.
1197   if (!isInlineAsm() && getOpcode() != TargetOpcode::STATEPOINT) {
1198     // Normal tied defs must be in the 0..TiedMax-1 range.
1199     if (MO.isUse())
1200       return TiedMax - 1;
1201     // MO is a def. Search for the tied use.
1202     for (unsigned i = TiedMax - 1, e = getNumOperands(); i != e; ++i) {
1203       const MachineOperand &UseMO = getOperand(i);
1204       if (UseMO.isReg() && UseMO.isUse() && UseMO.TiedTo == OpIdx + 1)
1205         return i;
1206     }
1207     llvm_unreachable("Can't find tied use");
1208   }
1209 
1210   if (getOpcode() == TargetOpcode::STATEPOINT) {
1211     // In STATEPOINT defs correspond 1-1 to GC pointer operands passed
1212     // on registers.
1213     StatepointOpers SO(this);
1214     unsigned CurUseIdx = SO.getFirstGCPtrIdx();
1215     assert(CurUseIdx != -1U && "only gc pointer statepoint operands can be tied");
1216     unsigned NumDefs = getNumDefs();
1217     for (unsigned CurDefIdx = 0; CurDefIdx < NumDefs; ++CurDefIdx) {
1218       while (!getOperand(CurUseIdx).isReg())
1219         CurUseIdx = StackMaps::getNextMetaArgIdx(this, CurUseIdx);
1220       if (OpIdx == CurDefIdx)
1221         return CurUseIdx;
1222       if (OpIdx == CurUseIdx)
1223         return CurDefIdx;
1224       CurUseIdx = StackMaps::getNextMetaArgIdx(this, CurUseIdx);
1225     }
1226     llvm_unreachable("Can't find tied use");
1227   }
1228 
1229   // Now deal with inline asm by parsing the operand group descriptor flags.
1230   // Find the beginning of each operand group.
1231   SmallVector<unsigned, 8> GroupIdx;
1232   unsigned OpIdxGroup = ~0u;
1233   unsigned NumOps;
1234   for (unsigned i = InlineAsm::MIOp_FirstOperand, e = getNumOperands(); i < e;
1235        i += NumOps) {
1236     const MachineOperand &FlagMO = getOperand(i);
1237     assert(FlagMO.isImm() && "Invalid tied operand on inline asm");
1238     unsigned CurGroup = GroupIdx.size();
1239     GroupIdx.push_back(i);
1240     const InlineAsm::Flag F(FlagMO.getImm());
1241     NumOps = 1 + F.getNumOperandRegisters();
1242     // OpIdx belongs to this operand group.
1243     if (OpIdx > i && OpIdx < i + NumOps)
1244       OpIdxGroup = CurGroup;
1245     unsigned TiedGroup;
1246     if (!F.isUseOperandTiedToDef(TiedGroup))
1247       continue;
1248     // Operands in this group are tied to operands in TiedGroup which must be
1249     // earlier. Find the number of operands between the two groups.
1250     unsigned Delta = i - GroupIdx[TiedGroup];
1251 
1252     // OpIdx is a use tied to TiedGroup.
1253     if (OpIdxGroup == CurGroup)
1254       return OpIdx - Delta;
1255 
1256     // OpIdx is a def tied to this use group.
1257     if (OpIdxGroup == TiedGroup)
1258       return OpIdx + Delta;
1259   }
1260   llvm_unreachable("Invalid tied operand on inline asm");
1261 }
1262 
1263 /// clearKillInfo - Clears kill flags on all operands.
1264 ///
1265 void MachineInstr::clearKillInfo() {
1266   for (MachineOperand &MO : all_uses())
1267     MO.setIsKill(false);
1268 }
1269 
1270 void MachineInstr::substituteRegister(Register FromReg, Register ToReg,
1271                                       unsigned SubIdx,
1272                                       const TargetRegisterInfo &RegInfo) {
1273   if (ToReg.isPhysical()) {
1274     if (SubIdx)
1275       ToReg = RegInfo.getSubReg(ToReg, SubIdx);
1276     for (MachineOperand &MO : operands()) {
1277       if (!MO.isReg() || MO.getReg() != FromReg)
1278         continue;
1279       MO.substPhysReg(ToReg, RegInfo);
1280     }
1281   } else {
1282     for (MachineOperand &MO : operands()) {
1283       if (!MO.isReg() || MO.getReg() != FromReg)
1284         continue;
1285       MO.substVirtReg(ToReg, SubIdx, RegInfo);
1286     }
1287   }
1288 }
1289 
1290 /// isSafeToMove - Return true if it is safe to move this instruction. If
1291 /// SawStore is set to true, it means that there is a store (or call) between
1292 /// the instruction's location and its intended destination.
1293 bool MachineInstr::isSafeToMove(bool &SawStore) const {
1294   // Ignore stuff that we obviously can't move.
1295   //
1296   // Treat volatile loads as stores. This is not strictly necessary for
1297   // volatiles, but it is required for atomic loads. It is not allowed to move
1298   // a load across an atomic load with Ordering > Monotonic.
1299   if (mayStore() || isCall() || isPHI() ||
1300       (mayLoad() && hasOrderedMemoryRef())) {
1301     SawStore = true;
1302     return false;
1303   }
1304 
1305   if (isPosition() || isDebugInstr() || isTerminator() ||
1306       mayRaiseFPException() || hasUnmodeledSideEffects() ||
1307       isJumpTableDebugInfo())
1308     return false;
1309 
1310   // See if this instruction does a load.  If so, we have to guarantee that the
1311   // loaded value doesn't change between the load and the its intended
1312   // destination. The check for isInvariantLoad gives the target the chance to
1313   // classify the load as always returning a constant, e.g. a constant pool
1314   // load.
1315   if (mayLoad() && !isDereferenceableInvariantLoad())
1316     // Otherwise, this is a real load.  If there is a store between the load and
1317     // end of block, we can't move it.
1318     return !SawStore;
1319 
1320   return true;
1321 }
1322 
1323 static bool MemOperandsHaveAlias(const MachineFrameInfo &MFI, AAResults *AA,
1324                                  bool UseTBAA, const MachineMemOperand *MMOa,
1325                                  const MachineMemOperand *MMOb) {
1326   // The following interface to AA is fashioned after DAGCombiner::isAlias and
1327   // operates with MachineMemOperand offset with some important assumptions:
1328   //   - LLVM fundamentally assumes flat address spaces.
1329   //   - MachineOperand offset can *only* result from legalization and cannot
1330   //     affect queries other than the trivial case of overlap checking.
1331   //   - These offsets never wrap and never step outside of allocated objects.
1332   //   - There should never be any negative offsets here.
1333   //
1334   // FIXME: Modify API to hide this math from "user"
1335   // Even before we go to AA we can reason locally about some memory objects. It
1336   // can save compile time, and possibly catch some corner cases not currently
1337   // covered.
1338 
1339   int64_t OffsetA = MMOa->getOffset();
1340   int64_t OffsetB = MMOb->getOffset();
1341   int64_t MinOffset = std::min(OffsetA, OffsetB);
1342 
1343   LocationSize WidthA = MMOa->getSize();
1344   LocationSize WidthB = MMOb->getSize();
1345   bool KnownWidthA = WidthA.hasValue();
1346   bool KnownWidthB = WidthB.hasValue();
1347   bool BothMMONonScalable = !WidthA.isScalable() && !WidthB.isScalable();
1348 
1349   const Value *ValA = MMOa->getValue();
1350   const Value *ValB = MMOb->getValue();
1351   bool SameVal = (ValA && ValB && (ValA == ValB));
1352   if (!SameVal) {
1353     const PseudoSourceValue *PSVa = MMOa->getPseudoValue();
1354     const PseudoSourceValue *PSVb = MMOb->getPseudoValue();
1355     if (PSVa && ValB && !PSVa->mayAlias(&MFI))
1356       return false;
1357     if (PSVb && ValA && !PSVb->mayAlias(&MFI))
1358       return false;
1359     if (PSVa && PSVb && (PSVa == PSVb))
1360       SameVal = true;
1361   }
1362 
1363   if (SameVal && BothMMONonScalable) {
1364     if (!KnownWidthA || !KnownWidthB)
1365       return true;
1366     int64_t MaxOffset = std::max(OffsetA, OffsetB);
1367     int64_t LowWidth = (MinOffset == OffsetA)
1368                            ? WidthA.getValue().getKnownMinValue()
1369                            : WidthB.getValue().getKnownMinValue();
1370     return (MinOffset + LowWidth > MaxOffset);
1371   }
1372 
1373   if (!AA)
1374     return true;
1375 
1376   if (!ValA || !ValB)
1377     return true;
1378 
1379   assert((OffsetA >= 0) && "Negative MachineMemOperand offset");
1380   assert((OffsetB >= 0) && "Negative MachineMemOperand offset");
1381 
1382   // If Scalable Location Size has non-zero offset, Width + Offset does not work
1383   // at the moment
1384   if ((WidthA.isScalable() && OffsetA > 0) ||
1385       (WidthB.isScalable() && OffsetB > 0))
1386     return true;
1387 
1388   int64_t OverlapA =
1389       KnownWidthA ? WidthA.getValue().getKnownMinValue() + OffsetA - MinOffset
1390                   : MemoryLocation::UnknownSize;
1391   int64_t OverlapB =
1392       KnownWidthB ? WidthB.getValue().getKnownMinValue() + OffsetB - MinOffset
1393                   : MemoryLocation::UnknownSize;
1394 
1395   LocationSize LocA = (WidthA.isScalable() || !KnownWidthA)
1396                           ? WidthA
1397                           : LocationSize::precise(OverlapA);
1398   LocationSize LocB = (WidthB.isScalable() || !KnownWidthB)
1399                           ? WidthB
1400                           : LocationSize::precise(OverlapB);
1401 
1402   return !AA->isNoAlias(
1403       MemoryLocation(ValA, LocA, UseTBAA ? MMOa->getAAInfo() : AAMDNodes()),
1404       MemoryLocation(ValB, LocB, UseTBAA ? MMOb->getAAInfo() : AAMDNodes()));
1405 }
1406 
1407 bool MachineInstr::mayAlias(AAResults *AA, const MachineInstr &Other,
1408                             bool UseTBAA) const {
1409   const MachineFunction *MF = getMF();
1410   const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
1411   const MachineFrameInfo &MFI = MF->getFrameInfo();
1412 
1413   // Exclude call instruction which may alter the memory but can not be handled
1414   // by this function.
1415   if (isCall() || Other.isCall())
1416     return true;
1417 
1418   // If neither instruction stores to memory, they can't alias in any
1419   // meaningful way, even if they read from the same address.
1420   if (!mayStore() && !Other.mayStore())
1421     return false;
1422 
1423   // Both instructions must be memory operations to be able to alias.
1424   if (!mayLoadOrStore() || !Other.mayLoadOrStore())
1425     return false;
1426 
1427   // Let the target decide if memory accesses cannot possibly overlap.
1428   if (TII->areMemAccessesTriviallyDisjoint(*this, Other))
1429     return false;
1430 
1431   // Memory operations without memory operands may access anything. Be
1432   // conservative and assume `MayAlias`.
1433   if (memoperands_empty() || Other.memoperands_empty())
1434     return true;
1435 
1436   // Skip if there are too many memory operands.
1437   auto NumChecks = getNumMemOperands() * Other.getNumMemOperands();
1438   if (NumChecks > TII->getMemOperandAACheckLimit())
1439     return true;
1440 
1441   // Check each pair of memory operands from both instructions, which can't
1442   // alias only if all pairs won't alias.
1443   for (auto *MMOa : memoperands())
1444     for (auto *MMOb : Other.memoperands())
1445       if (MemOperandsHaveAlias(MFI, AA, UseTBAA, MMOa, MMOb))
1446         return true;
1447 
1448   return false;
1449 }
1450 
1451 /// hasOrderedMemoryRef - Return true if this instruction may have an ordered
1452 /// or volatile memory reference, or if the information describing the memory
1453 /// reference is not available. Return false if it is known to have no ordered
1454 /// memory references.
1455 bool MachineInstr::hasOrderedMemoryRef() const {
1456   // An instruction known never to access memory won't have a volatile access.
1457   if (!mayStore() &&
1458       !mayLoad() &&
1459       !isCall() &&
1460       !hasUnmodeledSideEffects())
1461     return false;
1462 
1463   // Otherwise, if the instruction has no memory reference information,
1464   // conservatively assume it wasn't preserved.
1465   if (memoperands_empty())
1466     return true;
1467 
1468   // Check if any of our memory operands are ordered.
1469   return llvm::any_of(memoperands(), [](const MachineMemOperand *MMO) {
1470     return !MMO->isUnordered();
1471   });
1472 }
1473 
1474 /// isDereferenceableInvariantLoad - Return true if this instruction will never
1475 /// trap and is loading from a location whose value is invariant across a run of
1476 /// this function.
1477 bool MachineInstr::isDereferenceableInvariantLoad() const {
1478   // If the instruction doesn't load at all, it isn't an invariant load.
1479   if (!mayLoad())
1480     return false;
1481 
1482   // If the instruction has lost its memoperands, conservatively assume that
1483   // it may not be an invariant load.
1484   if (memoperands_empty())
1485     return false;
1486 
1487   const MachineFrameInfo &MFI = getParent()->getParent()->getFrameInfo();
1488 
1489   for (MachineMemOperand *MMO : memoperands()) {
1490     if (!MMO->isUnordered())
1491       // If the memory operand has ordering side effects, we can't move the
1492       // instruction.  Such an instruction is technically an invariant load,
1493       // but the caller code would need updated to expect that.
1494       return false;
1495     if (MMO->isStore()) return false;
1496     if (MMO->isInvariant() && MMO->isDereferenceable())
1497       continue;
1498 
1499     // A load from a constant PseudoSourceValue is invariant.
1500     if (const PseudoSourceValue *PSV = MMO->getPseudoValue()) {
1501       if (PSV->isConstant(&MFI))
1502         continue;
1503     }
1504 
1505     // Otherwise assume conservatively.
1506     return false;
1507   }
1508 
1509   // Everything checks out.
1510   return true;
1511 }
1512 
1513 /// isConstantValuePHI - If the specified instruction is a PHI that always
1514 /// merges together the same virtual register, return the register, otherwise
1515 /// return 0.
1516 unsigned MachineInstr::isConstantValuePHI() const {
1517   if (!isPHI())
1518     return 0;
1519   assert(getNumOperands() >= 3 &&
1520          "It's illegal to have a PHI without source operands");
1521 
1522   Register Reg = getOperand(1).getReg();
1523   for (unsigned i = 3, e = getNumOperands(); i < e; i += 2)
1524     if (getOperand(i).getReg() != Reg)
1525       return 0;
1526   return Reg;
1527 }
1528 
1529 bool MachineInstr::hasUnmodeledSideEffects() const {
1530   if (hasProperty(MCID::UnmodeledSideEffects))
1531     return true;
1532   if (isInlineAsm()) {
1533     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1534     if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
1535       return true;
1536   }
1537 
1538   return false;
1539 }
1540 
1541 bool MachineInstr::isLoadFoldBarrier() const {
1542   return mayStore() || isCall() ||
1543          (hasUnmodeledSideEffects() && !isPseudoProbe());
1544 }
1545 
1546 /// allDefsAreDead - Return true if all the defs of this instruction are dead.
1547 ///
1548 bool MachineInstr::allDefsAreDead() const {
1549   for (const MachineOperand &MO : all_defs())
1550     if (!MO.isDead())
1551       return false;
1552   return true;
1553 }
1554 
1555 bool MachineInstr::allImplicitDefsAreDead() const {
1556   for (const MachineOperand &MO : implicit_operands()) {
1557     if (!MO.isReg() || MO.isUse())
1558       continue;
1559     if (!MO.isDead())
1560       return false;
1561   }
1562   return true;
1563 }
1564 
1565 /// copyImplicitOps - Copy implicit register operands from specified
1566 /// instruction to this instruction.
1567 void MachineInstr::copyImplicitOps(MachineFunction &MF,
1568                                    const MachineInstr &MI) {
1569   for (const MachineOperand &MO :
1570        llvm::drop_begin(MI.operands(), MI.getDesc().getNumOperands()))
1571     if ((MO.isReg() && MO.isImplicit()) || MO.isRegMask())
1572       addOperand(MF, MO);
1573 }
1574 
1575 bool MachineInstr::hasComplexRegisterTies() const {
1576   const MCInstrDesc &MCID = getDesc();
1577   if (MCID.Opcode == TargetOpcode::STATEPOINT)
1578     return true;
1579   for (unsigned I = 0, E = getNumOperands(); I < E; ++I) {
1580     const auto &Operand = getOperand(I);
1581     if (!Operand.isReg() || Operand.isDef())
1582       // Ignore the defined registers as MCID marks only the uses as tied.
1583       continue;
1584     int ExpectedTiedIdx = MCID.getOperandConstraint(I, MCOI::TIED_TO);
1585     int TiedIdx = Operand.isTied() ? int(findTiedOperandIdx(I)) : -1;
1586     if (ExpectedTiedIdx != TiedIdx)
1587       return true;
1588   }
1589   return false;
1590 }
1591 
1592 LLT MachineInstr::getTypeToPrint(unsigned OpIdx, SmallBitVector &PrintedTypes,
1593                                  const MachineRegisterInfo &MRI) const {
1594   const MachineOperand &Op = getOperand(OpIdx);
1595   if (!Op.isReg())
1596     return LLT{};
1597 
1598   if (isVariadic() || OpIdx >= getNumExplicitOperands())
1599     return MRI.getType(Op.getReg());
1600 
1601   auto &OpInfo = getDesc().operands()[OpIdx];
1602   if (!OpInfo.isGenericType())
1603     return MRI.getType(Op.getReg());
1604 
1605   if (PrintedTypes[OpInfo.getGenericTypeIndex()])
1606     return LLT{};
1607 
1608   LLT TypeToPrint = MRI.getType(Op.getReg());
1609   // Don't mark the type index printed if it wasn't actually printed: maybe
1610   // another operand with the same type index has an actual type attached:
1611   if (TypeToPrint.isValid())
1612     PrintedTypes.set(OpInfo.getGenericTypeIndex());
1613   return TypeToPrint;
1614 }
1615 
1616 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
1617 LLVM_DUMP_METHOD void MachineInstr::dump() const {
1618   dbgs() << "  ";
1619   print(dbgs());
1620 }
1621 
1622 LLVM_DUMP_METHOD void MachineInstr::dumprImpl(
1623     const MachineRegisterInfo &MRI, unsigned Depth, unsigned MaxDepth,
1624     SmallPtrSetImpl<const MachineInstr *> &AlreadySeenInstrs) const {
1625   if (Depth >= MaxDepth)
1626     return;
1627   if (!AlreadySeenInstrs.insert(this).second)
1628     return;
1629   // PadToColumn always inserts at least one space.
1630   // Don't mess up the alignment if we don't want any space.
1631   if (Depth)
1632     fdbgs().PadToColumn(Depth * 2);
1633   print(fdbgs());
1634   for (const MachineOperand &MO : operands()) {
1635     if (!MO.isReg() || MO.isDef())
1636       continue;
1637     Register Reg = MO.getReg();
1638     if (Reg.isPhysical())
1639       continue;
1640     const MachineInstr *NewMI = MRI.getUniqueVRegDef(Reg);
1641     if (NewMI == nullptr)
1642       continue;
1643     NewMI->dumprImpl(MRI, Depth + 1, MaxDepth, AlreadySeenInstrs);
1644   }
1645 }
1646 
1647 LLVM_DUMP_METHOD void MachineInstr::dumpr(const MachineRegisterInfo &MRI,
1648                                           unsigned MaxDepth) const {
1649   SmallPtrSet<const MachineInstr *, 16> AlreadySeenInstrs;
1650   dumprImpl(MRI, 0, MaxDepth, AlreadySeenInstrs);
1651 }
1652 #endif
1653 
1654 void MachineInstr::print(raw_ostream &OS, bool IsStandalone, bool SkipOpers,
1655                          bool SkipDebugLoc, bool AddNewLine,
1656                          const TargetInstrInfo *TII) const {
1657   const Module *M = nullptr;
1658   const Function *F = nullptr;
1659   if (const MachineFunction *MF = getMFIfAvailable(*this)) {
1660     F = &MF->getFunction();
1661     M = F->getParent();
1662     if (!TII)
1663       TII = MF->getSubtarget().getInstrInfo();
1664   }
1665 
1666   ModuleSlotTracker MST(M);
1667   if (F)
1668     MST.incorporateFunction(*F);
1669   print(OS, MST, IsStandalone, SkipOpers, SkipDebugLoc, AddNewLine, TII);
1670 }
1671 
1672 void MachineInstr::print(raw_ostream &OS, ModuleSlotTracker &MST,
1673                          bool IsStandalone, bool SkipOpers, bool SkipDebugLoc,
1674                          bool AddNewLine, const TargetInstrInfo *TII) const {
1675   // We can be a bit tidier if we know the MachineFunction.
1676   const TargetRegisterInfo *TRI = nullptr;
1677   const MachineRegisterInfo *MRI = nullptr;
1678   const TargetIntrinsicInfo *IntrinsicInfo = nullptr;
1679   tryToGetTargetInfo(*this, TRI, MRI, IntrinsicInfo, TII);
1680 
1681   if (isCFIInstruction())
1682     assert(getNumOperands() == 1 && "Expected 1 operand in CFI instruction");
1683 
1684   SmallBitVector PrintedTypes(8);
1685   bool ShouldPrintRegisterTies = IsStandalone || hasComplexRegisterTies();
1686   auto getTiedOperandIdx = [&](unsigned OpIdx) {
1687     if (!ShouldPrintRegisterTies)
1688       return 0U;
1689     const MachineOperand &MO = getOperand(OpIdx);
1690     if (MO.isReg() && MO.isTied() && !MO.isDef())
1691       return findTiedOperandIdx(OpIdx);
1692     return 0U;
1693   };
1694   unsigned StartOp = 0;
1695   unsigned e = getNumOperands();
1696 
1697   // Print explicitly defined operands on the left of an assignment syntax.
1698   while (StartOp < e) {
1699     const MachineOperand &MO = getOperand(StartOp);
1700     if (!MO.isReg() || !MO.isDef() || MO.isImplicit())
1701       break;
1702 
1703     if (StartOp != 0)
1704       OS << ", ";
1705 
1706     LLT TypeToPrint = MRI ? getTypeToPrint(StartOp, PrintedTypes, *MRI) : LLT{};
1707     unsigned TiedOperandIdx = getTiedOperandIdx(StartOp);
1708     MO.print(OS, MST, TypeToPrint, StartOp, /*PrintDef=*/false, IsStandalone,
1709              ShouldPrintRegisterTies, TiedOperandIdx, TRI, IntrinsicInfo);
1710     ++StartOp;
1711   }
1712 
1713   if (StartOp != 0)
1714     OS << " = ";
1715 
1716   if (getFlag(MachineInstr::FrameSetup))
1717     OS << "frame-setup ";
1718   if (getFlag(MachineInstr::FrameDestroy))
1719     OS << "frame-destroy ";
1720   if (getFlag(MachineInstr::FmNoNans))
1721     OS << "nnan ";
1722   if (getFlag(MachineInstr::FmNoInfs))
1723     OS << "ninf ";
1724   if (getFlag(MachineInstr::FmNsz))
1725     OS << "nsz ";
1726   if (getFlag(MachineInstr::FmArcp))
1727     OS << "arcp ";
1728   if (getFlag(MachineInstr::FmContract))
1729     OS << "contract ";
1730   if (getFlag(MachineInstr::FmAfn))
1731     OS << "afn ";
1732   if (getFlag(MachineInstr::FmReassoc))
1733     OS << "reassoc ";
1734   if (getFlag(MachineInstr::NoUWrap))
1735     OS << "nuw ";
1736   if (getFlag(MachineInstr::NoSWrap))
1737     OS << "nsw ";
1738   if (getFlag(MachineInstr::IsExact))
1739     OS << "exact ";
1740   if (getFlag(MachineInstr::NoFPExcept))
1741     OS << "nofpexcept ";
1742   if (getFlag(MachineInstr::NoMerge))
1743     OS << "nomerge ";
1744   if (getFlag(MachineInstr::NonNeg))
1745     OS << "nneg ";
1746   if (getFlag(MachineInstr::Disjoint))
1747     OS << "disjoint ";
1748 
1749   // Print the opcode name.
1750   if (TII)
1751     OS << TII->getName(getOpcode());
1752   else
1753     OS << "UNKNOWN";
1754 
1755   if (SkipOpers)
1756     return;
1757 
1758   // Print the rest of the operands.
1759   bool FirstOp = true;
1760   unsigned AsmDescOp = ~0u;
1761   unsigned AsmOpCount = 0;
1762 
1763   if (isInlineAsm() && e >= InlineAsm::MIOp_FirstOperand) {
1764     // Print asm string.
1765     OS << " ";
1766     const unsigned OpIdx = InlineAsm::MIOp_AsmString;
1767     LLT TypeToPrint = MRI ? getTypeToPrint(OpIdx, PrintedTypes, *MRI) : LLT{};
1768     unsigned TiedOperandIdx = getTiedOperandIdx(OpIdx);
1769     getOperand(OpIdx).print(OS, MST, TypeToPrint, OpIdx, /*PrintDef=*/true, IsStandalone,
1770                             ShouldPrintRegisterTies, TiedOperandIdx, TRI,
1771                             IntrinsicInfo);
1772 
1773     // Print HasSideEffects, MayLoad, MayStore, IsAlignStack
1774     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1775     if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
1776       OS << " [sideeffect]";
1777     if (ExtraInfo & InlineAsm::Extra_MayLoad)
1778       OS << " [mayload]";
1779     if (ExtraInfo & InlineAsm::Extra_MayStore)
1780       OS << " [maystore]";
1781     if (ExtraInfo & InlineAsm::Extra_IsConvergent)
1782       OS << " [isconvergent]";
1783     if (ExtraInfo & InlineAsm::Extra_IsAlignStack)
1784       OS << " [alignstack]";
1785     if (getInlineAsmDialect() == InlineAsm::AD_ATT)
1786       OS << " [attdialect]";
1787     if (getInlineAsmDialect() == InlineAsm::AD_Intel)
1788       OS << " [inteldialect]";
1789 
1790     StartOp = AsmDescOp = InlineAsm::MIOp_FirstOperand;
1791     FirstOp = false;
1792   }
1793 
1794   for (unsigned i = StartOp, e = getNumOperands(); i != e; ++i) {
1795     const MachineOperand &MO = getOperand(i);
1796 
1797     if (FirstOp) FirstOp = false; else OS << ",";
1798     OS << " ";
1799 
1800     if (isDebugValueLike() && MO.isMetadata()) {
1801       // Pretty print DBG_VALUE* instructions.
1802       auto *DIV = dyn_cast<DILocalVariable>(MO.getMetadata());
1803       if (DIV && !DIV->getName().empty())
1804         OS << "!\"" << DIV->getName() << '\"';
1805       else {
1806         LLT TypeToPrint = MRI ? getTypeToPrint(i, PrintedTypes, *MRI) : LLT{};
1807         unsigned TiedOperandIdx = getTiedOperandIdx(i);
1808         MO.print(OS, MST, TypeToPrint, i, /*PrintDef=*/true, IsStandalone,
1809                  ShouldPrintRegisterTies, TiedOperandIdx, TRI, IntrinsicInfo);
1810       }
1811     } else if (isDebugLabel() && MO.isMetadata()) {
1812       // Pretty print DBG_LABEL instructions.
1813       auto *DIL = dyn_cast<DILabel>(MO.getMetadata());
1814       if (DIL && !DIL->getName().empty())
1815         OS << "\"" << DIL->getName() << '\"';
1816       else {
1817         LLT TypeToPrint = MRI ? getTypeToPrint(i, PrintedTypes, *MRI) : LLT{};
1818         unsigned TiedOperandIdx = getTiedOperandIdx(i);
1819         MO.print(OS, MST, TypeToPrint, i, /*PrintDef=*/true, IsStandalone,
1820                  ShouldPrintRegisterTies, TiedOperandIdx, TRI, IntrinsicInfo);
1821       }
1822     } else if (i == AsmDescOp && MO.isImm()) {
1823       // Pretty print the inline asm operand descriptor.
1824       OS << '$' << AsmOpCount++;
1825       unsigned Flag = MO.getImm();
1826       const InlineAsm::Flag F(Flag);
1827       OS << ":[";
1828       OS << F.getKindName();
1829 
1830       unsigned RCID;
1831       if (!F.isImmKind() && !F.isMemKind() && F.hasRegClassConstraint(RCID)) {
1832         if (TRI) {
1833           OS << ':' << TRI->getRegClassName(TRI->getRegClass(RCID));
1834         } else
1835           OS << ":RC" << RCID;
1836       }
1837 
1838       if (F.isMemKind()) {
1839         const InlineAsm::ConstraintCode MCID = F.getMemoryConstraintID();
1840         OS << ":" << InlineAsm::getMemConstraintName(MCID);
1841       }
1842 
1843       unsigned TiedTo;
1844       if (F.isUseOperandTiedToDef(TiedTo))
1845         OS << " tiedto:$" << TiedTo;
1846 
1847       if ((F.isRegDefKind() || F.isRegDefEarlyClobberKind() ||
1848            F.isRegUseKind()) &&
1849           F.getRegMayBeFolded()) {
1850         OS << " foldable";
1851       }
1852 
1853       OS << ']';
1854 
1855       // Compute the index of the next operand descriptor.
1856       AsmDescOp += 1 + F.getNumOperandRegisters();
1857     } else {
1858       LLT TypeToPrint = MRI ? getTypeToPrint(i, PrintedTypes, *MRI) : LLT{};
1859       unsigned TiedOperandIdx = getTiedOperandIdx(i);
1860       if (MO.isImm() && isOperandSubregIdx(i))
1861         MachineOperand::printSubRegIdx(OS, MO.getImm(), TRI);
1862       else
1863         MO.print(OS, MST, TypeToPrint, i, /*PrintDef=*/true, IsStandalone,
1864                  ShouldPrintRegisterTies, TiedOperandIdx, TRI, IntrinsicInfo);
1865     }
1866   }
1867 
1868   // Print any optional symbols attached to this instruction as-if they were
1869   // operands.
1870   if (MCSymbol *PreInstrSymbol = getPreInstrSymbol()) {
1871     if (!FirstOp) {
1872       FirstOp = false;
1873       OS << ',';
1874     }
1875     OS << " pre-instr-symbol ";
1876     MachineOperand::printSymbol(OS, *PreInstrSymbol);
1877   }
1878   if (MCSymbol *PostInstrSymbol = getPostInstrSymbol()) {
1879     if (!FirstOp) {
1880       FirstOp = false;
1881       OS << ',';
1882     }
1883     OS << " post-instr-symbol ";
1884     MachineOperand::printSymbol(OS, *PostInstrSymbol);
1885   }
1886   if (MDNode *HeapAllocMarker = getHeapAllocMarker()) {
1887     if (!FirstOp) {
1888       FirstOp = false;
1889       OS << ',';
1890     }
1891     OS << " heap-alloc-marker ";
1892     HeapAllocMarker->printAsOperand(OS, MST);
1893   }
1894   if (MDNode *PCSections = getPCSections()) {
1895     if (!FirstOp) {
1896       FirstOp = false;
1897       OS << ',';
1898     }
1899     OS << " pcsections ";
1900     PCSections->printAsOperand(OS, MST);
1901   }
1902   if (MDNode *MMRA = getMMRAMetadata()) {
1903     if (!FirstOp) {
1904       FirstOp = false;
1905       OS << ',';
1906     }
1907     OS << " mmra ";
1908     MMRA->printAsOperand(OS, MST);
1909   }
1910   if (uint32_t CFIType = getCFIType()) {
1911     if (!FirstOp)
1912       OS << ',';
1913     OS << " cfi-type " << CFIType;
1914   }
1915 
1916   if (DebugInstrNum) {
1917     if (!FirstOp)
1918       OS << ",";
1919     OS << " debug-instr-number " << DebugInstrNum;
1920   }
1921 
1922   if (!SkipDebugLoc) {
1923     if (const DebugLoc &DL = getDebugLoc()) {
1924       if (!FirstOp)
1925         OS << ',';
1926       OS << " debug-location ";
1927       DL->printAsOperand(OS, MST);
1928     }
1929   }
1930 
1931   if (!memoperands_empty()) {
1932     SmallVector<StringRef, 0> SSNs;
1933     const LLVMContext *Context = nullptr;
1934     std::unique_ptr<LLVMContext> CtxPtr;
1935     const MachineFrameInfo *MFI = nullptr;
1936     if (const MachineFunction *MF = getMFIfAvailable(*this)) {
1937       MFI = &MF->getFrameInfo();
1938       Context = &MF->getFunction().getContext();
1939     } else {
1940       CtxPtr = std::make_unique<LLVMContext>();
1941       Context = CtxPtr.get();
1942     }
1943 
1944     OS << " :: ";
1945     bool NeedComma = false;
1946     for (const MachineMemOperand *Op : memoperands()) {
1947       if (NeedComma)
1948         OS << ", ";
1949       Op->print(OS, MST, SSNs, *Context, MFI, TII);
1950       NeedComma = true;
1951     }
1952   }
1953 
1954   if (SkipDebugLoc)
1955     return;
1956 
1957   bool HaveSemi = false;
1958 
1959   // Print debug location information.
1960   if (const DebugLoc &DL = getDebugLoc()) {
1961     if (!HaveSemi) {
1962       OS << ';';
1963       HaveSemi = true;
1964     }
1965     OS << ' ';
1966     DL.print(OS);
1967   }
1968 
1969   // Print extra comments for DEBUG_VALUE and friends if they are well-formed.
1970   if ((isNonListDebugValue() && getNumOperands() >= 4) ||
1971       (isDebugValueList() && getNumOperands() >= 2) ||
1972       (isDebugRef() && getNumOperands() >= 3)) {
1973     if (getDebugVariableOp().isMetadata()) {
1974       if (!HaveSemi) {
1975         OS << ";";
1976         HaveSemi = true;
1977       }
1978       auto *DV = getDebugVariable();
1979       OS << " line no:" << DV->getLine();
1980       if (isIndirectDebugValue())
1981         OS << " indirect";
1982     }
1983   }
1984   // TODO: DBG_LABEL
1985 
1986   if (AddNewLine)
1987     OS << '\n';
1988 }
1989 
1990 bool MachineInstr::addRegisterKilled(Register IncomingReg,
1991                                      const TargetRegisterInfo *RegInfo,
1992                                      bool AddIfNotFound) {
1993   bool isPhysReg = IncomingReg.isPhysical();
1994   bool hasAliases = isPhysReg &&
1995     MCRegAliasIterator(IncomingReg, RegInfo, false).isValid();
1996   bool Found = false;
1997   SmallVector<unsigned,4> DeadOps;
1998   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1999     MachineOperand &MO = getOperand(i);
2000     if (!MO.isReg() || !MO.isUse() || MO.isUndef())
2001       continue;
2002 
2003     // DEBUG_VALUE nodes do not contribute to code generation and should
2004     // always be ignored. Failure to do so may result in trying to modify
2005     // KILL flags on DEBUG_VALUE nodes.
2006     if (MO.isDebug())
2007       continue;
2008 
2009     Register Reg = MO.getReg();
2010     if (!Reg)
2011       continue;
2012 
2013     if (Reg == IncomingReg) {
2014       if (!Found) {
2015         if (MO.isKill())
2016           // The register is already marked kill.
2017           return true;
2018         if (isPhysReg && isRegTiedToDefOperand(i))
2019           // Two-address uses of physregs must not be marked kill.
2020           return true;
2021         MO.setIsKill();
2022         Found = true;
2023       }
2024     } else if (hasAliases && MO.isKill() && Reg.isPhysical()) {
2025       // A super-register kill already exists.
2026       if (RegInfo->isSuperRegister(IncomingReg, Reg))
2027         return true;
2028       if (RegInfo->isSubRegister(IncomingReg, Reg))
2029         DeadOps.push_back(i);
2030     }
2031   }
2032 
2033   // Trim unneeded kill operands.
2034   while (!DeadOps.empty()) {
2035     unsigned OpIdx = DeadOps.back();
2036     if (getOperand(OpIdx).isImplicit() &&
2037         (!isInlineAsm() || findInlineAsmFlagIdx(OpIdx) < 0))
2038       removeOperand(OpIdx);
2039     else
2040       getOperand(OpIdx).setIsKill(false);
2041     DeadOps.pop_back();
2042   }
2043 
2044   // If not found, this means an alias of one of the operands is killed. Add a
2045   // new implicit operand if required.
2046   if (!Found && AddIfNotFound) {
2047     addOperand(MachineOperand::CreateReg(IncomingReg,
2048                                          false /*IsDef*/,
2049                                          true  /*IsImp*/,
2050                                          true  /*IsKill*/));
2051     return true;
2052   }
2053   return Found;
2054 }
2055 
2056 void MachineInstr::clearRegisterKills(Register Reg,
2057                                       const TargetRegisterInfo *RegInfo) {
2058   if (!Reg.isPhysical())
2059     RegInfo = nullptr;
2060   for (MachineOperand &MO : all_uses()) {
2061     if (!MO.isKill())
2062       continue;
2063     Register OpReg = MO.getReg();
2064     if ((RegInfo && RegInfo->regsOverlap(Reg, OpReg)) || Reg == OpReg)
2065       MO.setIsKill(false);
2066   }
2067 }
2068 
2069 bool MachineInstr::addRegisterDead(Register Reg,
2070                                    const TargetRegisterInfo *RegInfo,
2071                                    bool AddIfNotFound) {
2072   bool isPhysReg = Reg.isPhysical();
2073   bool hasAliases = isPhysReg &&
2074     MCRegAliasIterator(Reg, RegInfo, false).isValid();
2075   bool Found = false;
2076   SmallVector<unsigned,4> DeadOps;
2077   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
2078     MachineOperand &MO = getOperand(i);
2079     if (!MO.isReg() || !MO.isDef())
2080       continue;
2081     Register MOReg = MO.getReg();
2082     if (!MOReg)
2083       continue;
2084 
2085     if (MOReg == Reg) {
2086       MO.setIsDead();
2087       Found = true;
2088     } else if (hasAliases && MO.isDead() && MOReg.isPhysical()) {
2089       // There exists a super-register that's marked dead.
2090       if (RegInfo->isSuperRegister(Reg, MOReg))
2091         return true;
2092       if (RegInfo->isSubRegister(Reg, MOReg))
2093         DeadOps.push_back(i);
2094     }
2095   }
2096 
2097   // Trim unneeded dead operands.
2098   while (!DeadOps.empty()) {
2099     unsigned OpIdx = DeadOps.back();
2100     if (getOperand(OpIdx).isImplicit() &&
2101         (!isInlineAsm() || findInlineAsmFlagIdx(OpIdx) < 0))
2102       removeOperand(OpIdx);
2103     else
2104       getOperand(OpIdx).setIsDead(false);
2105     DeadOps.pop_back();
2106   }
2107 
2108   // If not found, this means an alias of one of the operands is dead. Add a
2109   // new implicit operand if required.
2110   if (Found || !AddIfNotFound)
2111     return Found;
2112 
2113   addOperand(MachineOperand::CreateReg(Reg,
2114                                        true  /*IsDef*/,
2115                                        true  /*IsImp*/,
2116                                        false /*IsKill*/,
2117                                        true  /*IsDead*/));
2118   return true;
2119 }
2120 
2121 void MachineInstr::clearRegisterDeads(Register Reg) {
2122   for (MachineOperand &MO : all_defs())
2123     if (MO.getReg() == Reg)
2124       MO.setIsDead(false);
2125 }
2126 
2127 void MachineInstr::setRegisterDefReadUndef(Register Reg, bool IsUndef) {
2128   for (MachineOperand &MO : all_defs())
2129     if (MO.getReg() == Reg && MO.getSubReg() != 0)
2130       MO.setIsUndef(IsUndef);
2131 }
2132 
2133 void MachineInstr::addRegisterDefined(Register Reg,
2134                                       const TargetRegisterInfo *RegInfo) {
2135   if (Reg.isPhysical()) {
2136     MachineOperand *MO = findRegisterDefOperand(Reg, RegInfo, false, false);
2137     if (MO)
2138       return;
2139   } else {
2140     for (const MachineOperand &MO : all_defs()) {
2141       if (MO.getReg() == Reg && MO.getSubReg() == 0)
2142         return;
2143     }
2144   }
2145   addOperand(MachineOperand::CreateReg(Reg,
2146                                        true  /*IsDef*/,
2147                                        true  /*IsImp*/));
2148 }
2149 
2150 void MachineInstr::setPhysRegsDeadExcept(ArrayRef<Register> UsedRegs,
2151                                          const TargetRegisterInfo &TRI) {
2152   bool HasRegMask = false;
2153   for (MachineOperand &MO : operands()) {
2154     if (MO.isRegMask()) {
2155       HasRegMask = true;
2156       continue;
2157     }
2158     if (!MO.isReg() || !MO.isDef()) continue;
2159     Register Reg = MO.getReg();
2160     if (!Reg.isPhysical())
2161       continue;
2162     // If there are no uses, including partial uses, the def is dead.
2163     if (llvm::none_of(UsedRegs,
2164                       [&](MCRegister Use) { return TRI.regsOverlap(Use, Reg); }))
2165       MO.setIsDead();
2166   }
2167 
2168   // This is a call with a register mask operand.
2169   // Mask clobbers are always dead, so add defs for the non-dead defines.
2170   if (HasRegMask)
2171     for (const Register &UsedReg : UsedRegs)
2172       addRegisterDefined(UsedReg, &TRI);
2173 }
2174 
2175 unsigned
2176 MachineInstrExpressionTrait::getHashValue(const MachineInstr* const &MI) {
2177   // Build up a buffer of hash code components.
2178   SmallVector<size_t, 16> HashComponents;
2179   HashComponents.reserve(MI->getNumOperands() + 1);
2180   HashComponents.push_back(MI->getOpcode());
2181   for (const MachineOperand &MO : MI->operands()) {
2182     if (MO.isReg() && MO.isDef() && MO.getReg().isVirtual())
2183       continue;  // Skip virtual register defs.
2184 
2185     HashComponents.push_back(hash_value(MO));
2186   }
2187   return hash_combine_range(HashComponents.begin(), HashComponents.end());
2188 }
2189 
2190 void MachineInstr::emitError(StringRef Msg) const {
2191   // Find the source location cookie.
2192   uint64_t LocCookie = 0;
2193   const MDNode *LocMD = nullptr;
2194   for (unsigned i = getNumOperands(); i != 0; --i) {
2195     if (getOperand(i-1).isMetadata() &&
2196         (LocMD = getOperand(i-1).getMetadata()) &&
2197         LocMD->getNumOperands() != 0) {
2198       if (const ConstantInt *CI =
2199               mdconst::dyn_extract<ConstantInt>(LocMD->getOperand(0))) {
2200         LocCookie = CI->getZExtValue();
2201         break;
2202       }
2203     }
2204   }
2205 
2206   if (const MachineBasicBlock *MBB = getParent())
2207     if (const MachineFunction *MF = MBB->getParent())
2208       return MF->getFunction().getContext().emitError(LocCookie, Msg);
2209   report_fatal_error(Msg);
2210 }
2211 
2212 MachineInstrBuilder llvm::BuildMI(MachineFunction &MF, const DebugLoc &DL,
2213                                   const MCInstrDesc &MCID, bool IsIndirect,
2214                                   Register Reg, const MDNode *Variable,
2215                                   const MDNode *Expr) {
2216   assert(isa<DILocalVariable>(Variable) && "not a variable");
2217   assert(cast<DIExpression>(Expr)->isValid() && "not an expression");
2218   assert(cast<DILocalVariable>(Variable)->isValidLocationForIntrinsic(DL) &&
2219          "Expected inlined-at fields to agree");
2220   auto MIB = BuildMI(MF, DL, MCID).addReg(Reg);
2221   if (IsIndirect)
2222     MIB.addImm(0U);
2223   else
2224     MIB.addReg(0U);
2225   return MIB.addMetadata(Variable).addMetadata(Expr);
2226 }
2227 
2228 MachineInstrBuilder llvm::BuildMI(MachineFunction &MF, const DebugLoc &DL,
2229                                   const MCInstrDesc &MCID, bool IsIndirect,
2230                                   ArrayRef<MachineOperand> DebugOps,
2231                                   const MDNode *Variable, const MDNode *Expr) {
2232   assert(isa<DILocalVariable>(Variable) && "not a variable");
2233   assert(cast<DIExpression>(Expr)->isValid() && "not an expression");
2234   assert(cast<DILocalVariable>(Variable)->isValidLocationForIntrinsic(DL) &&
2235          "Expected inlined-at fields to agree");
2236   if (MCID.Opcode == TargetOpcode::DBG_VALUE) {
2237     assert(DebugOps.size() == 1 &&
2238            "DBG_VALUE must contain exactly one debug operand");
2239     MachineOperand DebugOp = DebugOps[0];
2240     if (DebugOp.isReg())
2241       return BuildMI(MF, DL, MCID, IsIndirect, DebugOp.getReg(), Variable,
2242                      Expr);
2243 
2244     auto MIB = BuildMI(MF, DL, MCID).add(DebugOp);
2245     if (IsIndirect)
2246       MIB.addImm(0U);
2247     else
2248       MIB.addReg(0U);
2249     return MIB.addMetadata(Variable).addMetadata(Expr);
2250   }
2251 
2252   auto MIB = BuildMI(MF, DL, MCID);
2253   MIB.addMetadata(Variable).addMetadata(Expr);
2254   for (const MachineOperand &DebugOp : DebugOps)
2255     if (DebugOp.isReg())
2256       MIB.addReg(DebugOp.getReg());
2257     else
2258       MIB.add(DebugOp);
2259   return MIB;
2260 }
2261 
2262 MachineInstrBuilder llvm::BuildMI(MachineBasicBlock &BB,
2263                                   MachineBasicBlock::iterator I,
2264                                   const DebugLoc &DL, const MCInstrDesc &MCID,
2265                                   bool IsIndirect, Register Reg,
2266                                   const MDNode *Variable, const MDNode *Expr) {
2267   MachineFunction &MF = *BB.getParent();
2268   MachineInstr *MI = BuildMI(MF, DL, MCID, IsIndirect, Reg, Variable, Expr);
2269   BB.insert(I, MI);
2270   return MachineInstrBuilder(MF, MI);
2271 }
2272 
2273 MachineInstrBuilder llvm::BuildMI(MachineBasicBlock &BB,
2274                                   MachineBasicBlock::iterator I,
2275                                   const DebugLoc &DL, const MCInstrDesc &MCID,
2276                                   bool IsIndirect,
2277                                   ArrayRef<MachineOperand> DebugOps,
2278                                   const MDNode *Variable, const MDNode *Expr) {
2279   MachineFunction &MF = *BB.getParent();
2280   MachineInstr *MI =
2281       BuildMI(MF, DL, MCID, IsIndirect, DebugOps, Variable, Expr);
2282   BB.insert(I, MI);
2283   return MachineInstrBuilder(MF, *MI);
2284 }
2285 
2286 /// Compute the new DIExpression to use with a DBG_VALUE for a spill slot.
2287 /// This prepends DW_OP_deref when spilling an indirect DBG_VALUE.
2288 static const DIExpression *computeExprForSpill(
2289     const MachineInstr &MI,
2290     const SmallVectorImpl<const MachineOperand *> &SpilledOperands) {
2291   assert(MI.getDebugVariable()->isValidLocationForIntrinsic(MI.getDebugLoc()) &&
2292          "Expected inlined-at fields to agree");
2293 
2294   const DIExpression *Expr = MI.getDebugExpression();
2295   if (MI.isIndirectDebugValue()) {
2296     assert(MI.getDebugOffset().getImm() == 0 &&
2297            "DBG_VALUE with nonzero offset");
2298     Expr = DIExpression::prepend(Expr, DIExpression::DerefBefore);
2299   } else if (MI.isDebugValueList()) {
2300     // We will replace the spilled register with a frame index, so
2301     // immediately deref all references to the spilled register.
2302     std::array<uint64_t, 1> Ops{{dwarf::DW_OP_deref}};
2303     for (const MachineOperand *Op : SpilledOperands) {
2304       unsigned OpIdx = MI.getDebugOperandIndex(Op);
2305       Expr = DIExpression::appendOpsToArg(Expr, Ops, OpIdx);
2306     }
2307   }
2308   return Expr;
2309 }
2310 static const DIExpression *computeExprForSpill(const MachineInstr &MI,
2311                                                Register SpillReg) {
2312   assert(MI.hasDebugOperandForReg(SpillReg) && "Spill Reg is not used in MI.");
2313   SmallVector<const MachineOperand *> SpillOperands;
2314   for (const MachineOperand &Op : MI.getDebugOperandsForReg(SpillReg))
2315     SpillOperands.push_back(&Op);
2316   return computeExprForSpill(MI, SpillOperands);
2317 }
2318 
2319 MachineInstr *llvm::buildDbgValueForSpill(MachineBasicBlock &BB,
2320                                           MachineBasicBlock::iterator I,
2321                                           const MachineInstr &Orig,
2322                                           int FrameIndex, Register SpillReg) {
2323   assert(!Orig.isDebugRef() &&
2324          "DBG_INSTR_REF should not reference a virtual register.");
2325   const DIExpression *Expr = computeExprForSpill(Orig, SpillReg);
2326   MachineInstrBuilder NewMI =
2327       BuildMI(BB, I, Orig.getDebugLoc(), Orig.getDesc());
2328   // Non-Variadic Operands: Location, Offset, Variable, Expression
2329   // Variadic Operands:     Variable, Expression, Locations...
2330   if (Orig.isNonListDebugValue())
2331     NewMI.addFrameIndex(FrameIndex).addImm(0U);
2332   NewMI.addMetadata(Orig.getDebugVariable()).addMetadata(Expr);
2333   if (Orig.isDebugValueList()) {
2334     for (const MachineOperand &Op : Orig.debug_operands())
2335       if (Op.isReg() && Op.getReg() == SpillReg)
2336         NewMI.addFrameIndex(FrameIndex);
2337       else
2338         NewMI.add(MachineOperand(Op));
2339   }
2340   return NewMI;
2341 }
2342 MachineInstr *llvm::buildDbgValueForSpill(
2343     MachineBasicBlock &BB, MachineBasicBlock::iterator I,
2344     const MachineInstr &Orig, int FrameIndex,
2345     const SmallVectorImpl<const MachineOperand *> &SpilledOperands) {
2346   const DIExpression *Expr = computeExprForSpill(Orig, SpilledOperands);
2347   MachineInstrBuilder NewMI =
2348       BuildMI(BB, I, Orig.getDebugLoc(), Orig.getDesc());
2349   // Non-Variadic Operands: Location, Offset, Variable, Expression
2350   // Variadic Operands:     Variable, Expression, Locations...
2351   if (Orig.isNonListDebugValue())
2352     NewMI.addFrameIndex(FrameIndex).addImm(0U);
2353   NewMI.addMetadata(Orig.getDebugVariable()).addMetadata(Expr);
2354   if (Orig.isDebugValueList()) {
2355     for (const MachineOperand &Op : Orig.debug_operands())
2356       if (is_contained(SpilledOperands, &Op))
2357         NewMI.addFrameIndex(FrameIndex);
2358       else
2359         NewMI.add(MachineOperand(Op));
2360   }
2361   return NewMI;
2362 }
2363 
2364 void llvm::updateDbgValueForSpill(MachineInstr &Orig, int FrameIndex,
2365                                   Register Reg) {
2366   const DIExpression *Expr = computeExprForSpill(Orig, Reg);
2367   if (Orig.isNonListDebugValue())
2368     Orig.getDebugOffset().ChangeToImmediate(0U);
2369   for (MachineOperand &Op : Orig.getDebugOperandsForReg(Reg))
2370     Op.ChangeToFrameIndex(FrameIndex);
2371   Orig.getDebugExpressionOp().setMetadata(Expr);
2372 }
2373 
2374 void MachineInstr::collectDebugValues(
2375                                 SmallVectorImpl<MachineInstr *> &DbgValues) {
2376   MachineInstr &MI = *this;
2377   if (!MI.getOperand(0).isReg())
2378     return;
2379 
2380   MachineBasicBlock::iterator DI = MI; ++DI;
2381   for (MachineBasicBlock::iterator DE = MI.getParent()->end();
2382        DI != DE; ++DI) {
2383     if (!DI->isDebugValue())
2384       return;
2385     if (DI->hasDebugOperandForReg(MI.getOperand(0).getReg()))
2386       DbgValues.push_back(&*DI);
2387   }
2388 }
2389 
2390 void MachineInstr::changeDebugValuesDefReg(Register Reg) {
2391   // Collect matching debug values.
2392   SmallVector<MachineInstr *, 2> DbgValues;
2393 
2394   if (!getOperand(0).isReg())
2395     return;
2396 
2397   Register DefReg = getOperand(0).getReg();
2398   auto *MRI = getRegInfo();
2399   for (auto &MO : MRI->use_operands(DefReg)) {
2400     auto *DI = MO.getParent();
2401     if (!DI->isDebugValue())
2402       continue;
2403     if (DI->hasDebugOperandForReg(DefReg)) {
2404       DbgValues.push_back(DI);
2405     }
2406   }
2407 
2408   // Propagate Reg to debug value instructions.
2409   for (auto *DBI : DbgValues)
2410     for (MachineOperand &Op : DBI->getDebugOperandsForReg(DefReg))
2411       Op.setReg(Reg);
2412 }
2413 
2414 using MMOList = SmallVector<const MachineMemOperand *, 2>;
2415 
2416 static LocationSize getSpillSlotSize(const MMOList &Accesses,
2417                                      const MachineFrameInfo &MFI) {
2418   uint64_t Size = 0;
2419   for (const auto *A : Accesses) {
2420     if (MFI.isSpillSlotObjectIndex(
2421             cast<FixedStackPseudoSourceValue>(A->getPseudoValue())
2422                 ->getFrameIndex())) {
2423       LocationSize S = A->getSize();
2424       if (!S.hasValue())
2425         return LocationSize::beforeOrAfterPointer();
2426       Size += S.getValue();
2427     }
2428   }
2429   return Size;
2430 }
2431 
2432 std::optional<LocationSize>
2433 MachineInstr::getSpillSize(const TargetInstrInfo *TII) const {
2434   int FI;
2435   if (TII->isStoreToStackSlotPostFE(*this, FI)) {
2436     const MachineFrameInfo &MFI = getMF()->getFrameInfo();
2437     if (MFI.isSpillSlotObjectIndex(FI))
2438       return (*memoperands_begin())->getSize();
2439   }
2440   return std::nullopt;
2441 }
2442 
2443 std::optional<LocationSize>
2444 MachineInstr::getFoldedSpillSize(const TargetInstrInfo *TII) const {
2445   MMOList Accesses;
2446   if (TII->hasStoreToStackSlot(*this, Accesses))
2447     return getSpillSlotSize(Accesses, getMF()->getFrameInfo());
2448   return std::nullopt;
2449 }
2450 
2451 std::optional<LocationSize>
2452 MachineInstr::getRestoreSize(const TargetInstrInfo *TII) const {
2453   int FI;
2454   if (TII->isLoadFromStackSlotPostFE(*this, FI)) {
2455     const MachineFrameInfo &MFI = getMF()->getFrameInfo();
2456     if (MFI.isSpillSlotObjectIndex(FI))
2457       return (*memoperands_begin())->getSize();
2458   }
2459   return std::nullopt;
2460 }
2461 
2462 std::optional<LocationSize>
2463 MachineInstr::getFoldedRestoreSize(const TargetInstrInfo *TII) const {
2464   MMOList Accesses;
2465   if (TII->hasLoadFromStackSlot(*this, Accesses))
2466     return getSpillSlotSize(Accesses, getMF()->getFrameInfo());
2467   return std::nullopt;
2468 }
2469 
2470 unsigned MachineInstr::getDebugInstrNum() {
2471   if (DebugInstrNum == 0)
2472     DebugInstrNum = getParent()->getParent()->getNewDebugInstrNum();
2473   return DebugInstrNum;
2474 }
2475 
2476 unsigned MachineInstr::getDebugInstrNum(MachineFunction &MF) {
2477   if (DebugInstrNum == 0)
2478     DebugInstrNum = MF.getNewDebugInstrNum();
2479   return DebugInstrNum;
2480 }
2481 
2482 std::tuple<LLT, LLT> MachineInstr::getFirst2LLTs() const {
2483   return std::tuple(getRegInfo()->getType(getOperand(0).getReg()),
2484                     getRegInfo()->getType(getOperand(1).getReg()));
2485 }
2486 
2487 std::tuple<LLT, LLT, LLT> MachineInstr::getFirst3LLTs() const {
2488   return std::tuple(getRegInfo()->getType(getOperand(0).getReg()),
2489                     getRegInfo()->getType(getOperand(1).getReg()),
2490                     getRegInfo()->getType(getOperand(2).getReg()));
2491 }
2492 
2493 std::tuple<LLT, LLT, LLT, LLT> MachineInstr::getFirst4LLTs() const {
2494   return std::tuple(getRegInfo()->getType(getOperand(0).getReg()),
2495                     getRegInfo()->getType(getOperand(1).getReg()),
2496                     getRegInfo()->getType(getOperand(2).getReg()),
2497                     getRegInfo()->getType(getOperand(3).getReg()));
2498 }
2499 
2500 std::tuple<LLT, LLT, LLT, LLT, LLT> MachineInstr::getFirst5LLTs() const {
2501   return std::tuple(getRegInfo()->getType(getOperand(0).getReg()),
2502                     getRegInfo()->getType(getOperand(1).getReg()),
2503                     getRegInfo()->getType(getOperand(2).getReg()),
2504                     getRegInfo()->getType(getOperand(3).getReg()),
2505                     getRegInfo()->getType(getOperand(4).getReg()));
2506 }
2507 
2508 std::tuple<Register, LLT, Register, LLT>
2509 MachineInstr::getFirst2RegLLTs() const {
2510   Register Reg0 = getOperand(0).getReg();
2511   Register Reg1 = getOperand(1).getReg();
2512   return std::tuple(Reg0, getRegInfo()->getType(Reg0), Reg1,
2513                     getRegInfo()->getType(Reg1));
2514 }
2515 
2516 std::tuple<Register, LLT, Register, LLT, Register, LLT>
2517 MachineInstr::getFirst3RegLLTs() const {
2518   Register Reg0 = getOperand(0).getReg();
2519   Register Reg1 = getOperand(1).getReg();
2520   Register Reg2 = getOperand(2).getReg();
2521   return std::tuple(Reg0, getRegInfo()->getType(Reg0), Reg1,
2522                     getRegInfo()->getType(Reg1), Reg2,
2523                     getRegInfo()->getType(Reg2));
2524 }
2525 
2526 std::tuple<Register, LLT, Register, LLT, Register, LLT, Register, LLT>
2527 MachineInstr::getFirst4RegLLTs() const {
2528   Register Reg0 = getOperand(0).getReg();
2529   Register Reg1 = getOperand(1).getReg();
2530   Register Reg2 = getOperand(2).getReg();
2531   Register Reg3 = getOperand(3).getReg();
2532   return std::tuple(
2533       Reg0, getRegInfo()->getType(Reg0), Reg1, getRegInfo()->getType(Reg1),
2534       Reg2, getRegInfo()->getType(Reg2), Reg3, getRegInfo()->getType(Reg3));
2535 }
2536 
2537 std::tuple<Register, LLT, Register, LLT, Register, LLT, Register, LLT, Register,
2538            LLT>
2539 MachineInstr::getFirst5RegLLTs() const {
2540   Register Reg0 = getOperand(0).getReg();
2541   Register Reg1 = getOperand(1).getReg();
2542   Register Reg2 = getOperand(2).getReg();
2543   Register Reg3 = getOperand(3).getReg();
2544   Register Reg4 = getOperand(4).getReg();
2545   return std::tuple(
2546       Reg0, getRegInfo()->getType(Reg0), Reg1, getRegInfo()->getType(Reg1),
2547       Reg2, getRegInfo()->getType(Reg2), Reg3, getRegInfo()->getType(Reg3),
2548       Reg4, getRegInfo()->getType(Reg4));
2549 }
2550 
2551 void MachineInstr::insert(mop_iterator InsertBefore,
2552                           ArrayRef<MachineOperand> Ops) {
2553   assert(InsertBefore != nullptr && "invalid iterator");
2554   assert(InsertBefore->getParent() == this &&
2555          "iterator points to operand of other inst");
2556   if (Ops.empty())
2557     return;
2558 
2559   // Do one pass to untie operands.
2560   SmallDenseMap<unsigned, unsigned> TiedOpIndices;
2561   for (const MachineOperand &MO : operands()) {
2562     if (MO.isReg() && MO.isTied()) {
2563       unsigned OpNo = getOperandNo(&MO);
2564       unsigned TiedTo = findTiedOperandIdx(OpNo);
2565       TiedOpIndices[OpNo] = TiedTo;
2566       untieRegOperand(OpNo);
2567     }
2568   }
2569 
2570   unsigned OpIdx = getOperandNo(InsertBefore);
2571   unsigned NumOperands = getNumOperands();
2572   unsigned OpsToMove = NumOperands - OpIdx;
2573 
2574   SmallVector<MachineOperand> MovingOps;
2575   MovingOps.reserve(OpsToMove);
2576 
2577   for (unsigned I = 0; I < OpsToMove; ++I) {
2578     MovingOps.emplace_back(getOperand(OpIdx));
2579     removeOperand(OpIdx);
2580   }
2581   for (const MachineOperand &MO : Ops)
2582     addOperand(MO);
2583   for (const MachineOperand &OpMoved : MovingOps)
2584     addOperand(OpMoved);
2585 
2586   // Re-tie operands.
2587   for (auto [Tie1, Tie2] : TiedOpIndices) {
2588     if (Tie1 >= OpIdx)
2589       Tie1 += Ops.size();
2590     if (Tie2 >= OpIdx)
2591       Tie2 += Ops.size();
2592     tieOperands(Tie1, Tie2);
2593   }
2594 }
2595 
2596 bool MachineInstr::mayFoldInlineAsmRegOp(unsigned OpId) const {
2597   assert(OpId && "expected non-zero operand id");
2598   assert(isInlineAsm() && "should only be used on inline asm");
2599 
2600   if (!getOperand(OpId).isReg())
2601     return false;
2602 
2603   const MachineOperand &MD = getOperand(OpId - 1);
2604   if (!MD.isImm())
2605     return false;
2606 
2607   InlineAsm::Flag F(MD.getImm());
2608   if (F.isRegUseKind() || F.isRegDefKind() || F.isRegDefEarlyClobberKind())
2609     return F.getRegMayBeFolded();
2610   return false;
2611 }
2612