xref: /freebsd/contrib/llvm-project/llvm/lib/CodeGen/MachineInstr.cpp (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
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 
getMFIfAvailable(const MachineInstr & MI)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.
tryToGetTargetInfo(const MachineInstr & MI,const TargetRegisterInfo * & TRI,const MachineRegisterInfo * & MRI,const TargetIntrinsicInfo * & IntrinsicInfo,const TargetInstrInfo * & TII)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 
addImplicitDefUseOperands(MachineFunction & MF)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.
MachineInstr(MachineFunction & MF,const MCInstrDesc & TID,DebugLoc DL,bool NoImp)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.
MachineInstr(MachineFunction & MF,const MachineInstr & MI)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 
setDesc(const MCInstrDesc & TID)143 void MachineInstr::setDesc(const MCInstrDesc &TID) {
144   if (getParent())
145     getMF()->handleChangeDesc(*this, TID);
146   MCID = &TID;
147   Opcode = TID.Opcode;
148 }
149 
moveBefore(MachineInstr * MovePos)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.
getRegInfo()157 MachineRegisterInfo *MachineInstr::getRegInfo() {
158   if (MachineBasicBlock *MBB = getParent())
159     return &MBB->getParent()->getRegInfo();
160   return nullptr;
161 }
162 
getRegInfo() const163 const MachineRegisterInfo *MachineInstr::getRegInfo() const {
164   if (const MachineBasicBlock *MBB = getParent())
165     return &MBB->getParent()->getRegInfo();
166   return nullptr;
167 }
168 
removeRegOperandsFromUseLists(MachineRegisterInfo & MRI)169 void MachineInstr::removeRegOperandsFromUseLists(MachineRegisterInfo &MRI) {
170   for (MachineOperand &MO : operands())
171     if (MO.isReg())
172       MRI.removeRegOperandFromUseList(&MO);
173 }
174 
addRegOperandsToUseLists(MachineRegisterInfo & MRI)175 void MachineInstr::addRegOperandsToUseLists(MachineRegisterInfo &MRI) {
176   for (MachineOperand &MO : operands())
177     if (MO.isReg())
178       MRI.addRegOperandToUseList(&MO);
179 }
180 
addOperand(const MachineOperand & Op)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.
moveOperands(MachineOperand * Dst,MachineOperand * Src,unsigned NumOps,MachineRegisterInfo * MRI)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).
addOperand(MachineFunction & MF,const MachineOperand & Op)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 
removeOperand(unsigned OpNo)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 
setExtraInfo(MachineFunction & MF,ArrayRef<MachineMemOperand * > MMOs,MCSymbol * PreInstrSymbol,MCSymbol * PostInstrSymbol,MDNode * HeapAllocMarker,MDNode * PCSections,uint32_t CFIType,MDNode * MMRAs)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 
dropMemRefs(MachineFunction & MF)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 
setMemRefs(MachineFunction & MF,ArrayRef<MachineMemOperand * > MMOs)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 
addMemOperand(MachineFunction & MF,MachineMemOperand * MO)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 
cloneMemRefs(MachineFunction & MF,const MachineInstr & MI)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.
hasIdenticalMMOs(ArrayRef<MachineMemOperand * > LHS,ArrayRef<MachineMemOperand * > RHS)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 
cloneMergedMemRefs(MachineFunction & MF,ArrayRef<const MachineInstr * > MIs)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 
setPreInstrSymbol(MachineFunction & MF,MCSymbol * Symbol)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 
setPostInstrSymbol(MachineFunction & MF,MCSymbol * Symbol)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 
setHeapAllocMarker(MachineFunction & MF,MDNode * Marker)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 
setPCSections(MachineFunction & MF,MDNode * PCSections)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 
setCFIType(MachineFunction & MF,uint32_t Type)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 
setMMRAMetadata(MachineFunction & MF,MDNode * MMRAs)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 
cloneInstrSymbols(MachineFunction & MF,const MachineInstr & MI)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 
mergeFlagsWith(const MachineInstr & Other) const561 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 
copyFlagsFromInstruction(const Instruction & I)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 
copyIRFlags(const Instruction & I)629 void MachineInstr::copyIRFlags(const Instruction &I) {
630   Flags = copyFlagsFromInstruction(I);
631 }
632 
hasPropertyInBundle(uint64_t Mask,QueryType Type) const633 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 
isIdenticalTo(const MachineInstr & Other,MICheckType Check) const649 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 
isEquivalentDbgInstr(const MachineInstr & Other) const728 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 
getMF() const747 const MachineFunction *MachineInstr::getMF() const {
748   return getParent()->getParent();
749 }
750 
removeFromParent()751 MachineInstr *MachineInstr::removeFromParent() {
752   assert(getParent() && "Not embedded in a basic block!");
753   return getParent()->remove(this);
754 }
755 
removeFromBundle()756 MachineInstr *MachineInstr::removeFromBundle() {
757   assert(getParent() && "Not embedded in a basic block!");
758   return getParent()->remove_instr(this);
759 }
760 
eraseFromParent()761 void MachineInstr::eraseFromParent() {
762   assert(getParent() && "Not embedded in a basic block!");
763   getParent()->erase(this);
764 }
765 
eraseFromBundle()766 void MachineInstr::eraseFromBundle() {
767   assert(getParent() && "Not embedded in a basic block!");
768   getParent()->erase_instr(this);
769 }
770 
isCandidateForCallSiteEntry(QueryType Type) const771 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 
shouldUpdateCallSiteInfo() const784 bool MachineInstr::shouldUpdateCallSiteInfo() const {
785   if (isBundle())
786     return isCandidateForCallSiteEntry(MachineInstr::AnyInBundle);
787   return isCandidateForCallSiteEntry();
788 }
789 
getNumExplicitOperands() const790 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 
getNumExplicitDefs() const809 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 
bundleWithPred()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 
bundleWithSucc()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 
unbundleFromPred()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 
unbundleFromSucc()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 
isStackAligningInlineAsm() const859 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 
getInlineAsmDialect() const868 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 
findInlineAsmFlagIdx(unsigned OpIdx,unsigned * GroupNo) const874 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 
getDebugLabel() const903 const DILabel *MachineInstr::getDebugLabel() const {
904   assert(isDebugLabel() && "not a DBG_LABEL");
905   return cast<DILabel>(getOperand(0).getMetadata());
906 }
907 
getDebugVariableOp() const908 const MachineOperand &MachineInstr::getDebugVariableOp() const {
909   assert((isDebugValueLike()) && "not a DBG_VALUE*");
910   unsigned VariableOp = isNonListDebugValue() ? 2 : 0;
911   return getOperand(VariableOp);
912 }
913 
getDebugVariableOp()914 MachineOperand &MachineInstr::getDebugVariableOp() {
915   assert((isDebugValueLike()) && "not a DBG_VALUE*");
916   unsigned VariableOp = isNonListDebugValue() ? 2 : 0;
917   return getOperand(VariableOp);
918 }
919 
getDebugVariable() const920 const DILocalVariable *MachineInstr::getDebugVariable() const {
921   return cast<DILocalVariable>(getDebugVariableOp().getMetadata());
922 }
923 
getDebugExpressionOp() const924 const MachineOperand &MachineInstr::getDebugExpressionOp() const {
925   assert((isDebugValueLike()) && "not a DBG_VALUE*");
926   unsigned ExpressionOp = isNonListDebugValue() ? 3 : 1;
927   return getOperand(ExpressionOp);
928 }
929 
getDebugExpressionOp()930 MachineOperand &MachineInstr::getDebugExpressionOp() {
931   assert((isDebugValueLike()) && "not a DBG_VALUE*");
932   unsigned ExpressionOp = isNonListDebugValue() ? 3 : 1;
933   return getOperand(ExpressionOp);
934 }
935 
getDebugExpression() const936 const DIExpression *MachineInstr::getDebugExpression() const {
937   return cast<DIExpression>(getDebugExpressionOp().getMetadata());
938 }
939 
isDebugEntryValue() const940 bool MachineInstr::isDebugEntryValue() const {
941   return isDebugValue() && getDebugExpression()->isEntryValue();
942 }
943 
944 const TargetRegisterClass*
getRegClassConstraint(unsigned OpIdx,const TargetInstrInfo * TII,const TargetRegisterInfo * TRI) const945 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 
getRegClassConstraintEffectForVReg(Register Reg,const TargetRegisterClass * CurRC,const TargetInstrInfo * TII,const TargetRegisterInfo * TRI,bool ExploreBundle) const982 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 
getRegClassConstraintEffectForVRegImpl(unsigned OpIdx,Register Reg,const TargetRegisterClass * CurRC,const TargetInstrInfo * TII,const TargetRegisterInfo * TRI) const999 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 
getRegClassConstraintEffect(unsigned OpIdx,const TargetRegisterClass * CurRC,const TargetInstrInfo * TII,const TargetRegisterInfo * TRI) const1011 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.
getBundleSize() const1031 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).
hasRegisterImplicitUseOperand(Register Reg) const1043 bool MachineInstr::hasRegisterImplicitUseOperand(Register Reg) const {
1044   for (const MachineOperand &MO : operands()) {
1045     if (MO.isReg() && MO.isUse() && MO.isImplicit() && MO.getReg() == Reg)
1046       return true;
1047   }
1048   return false;
1049 }
1050 
1051 /// findRegisterUseOperandIdx() - Returns the MachineOperand that is a use of
1052 /// the specific register or -1 if it is not found. It further tightens
1053 /// the search criteria to a use that kills the register if isKill is true.
findRegisterUseOperandIdx(Register Reg,const TargetRegisterInfo * TRI,bool isKill) const1054 int MachineInstr::findRegisterUseOperandIdx(Register Reg,
1055                                             const TargetRegisterInfo *TRI,
1056                                             bool isKill) const {
1057   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1058     const MachineOperand &MO = getOperand(i);
1059     if (!MO.isReg() || !MO.isUse())
1060       continue;
1061     Register MOReg = MO.getReg();
1062     if (!MOReg)
1063       continue;
1064     if (MOReg == Reg || (TRI && Reg && MOReg && TRI->regsOverlap(MOReg, Reg)))
1065       if (!isKill || MO.isKill())
1066         return i;
1067   }
1068   return -1;
1069 }
1070 
1071 /// readsWritesVirtualRegister - Return a pair of bools (reads, writes)
1072 /// indicating if this instruction reads or writes Reg. This also considers
1073 /// partial defines.
1074 std::pair<bool,bool>
readsWritesVirtualRegister(Register Reg,SmallVectorImpl<unsigned> * Ops) const1075 MachineInstr::readsWritesVirtualRegister(Register Reg,
1076                                          SmallVectorImpl<unsigned> *Ops) const {
1077   bool PartDef = false; // Partial redefine.
1078   bool FullDef = false; // Full define.
1079   bool Use = false;
1080 
1081   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1082     const MachineOperand &MO = getOperand(i);
1083     if (!MO.isReg() || MO.getReg() != Reg)
1084       continue;
1085     if (Ops)
1086       Ops->push_back(i);
1087     if (MO.isUse())
1088       Use |= !MO.isUndef();
1089     else if (MO.getSubReg() && !MO.isUndef())
1090       // A partial def undef doesn't count as reading the register.
1091       PartDef = true;
1092     else
1093       FullDef = true;
1094   }
1095   // A partial redefine uses Reg unless there is also a full define.
1096   return std::make_pair(Use || (PartDef && !FullDef), PartDef || FullDef);
1097 }
1098 
1099 /// findRegisterDefOperandIdx() - Returns the operand index that is a def of
1100 /// the specified register or -1 if it is not found. If isDead is true, defs
1101 /// that are not dead are skipped. If TargetRegisterInfo is non-null, then it
1102 /// also checks if there is a def of a super-register.
findRegisterDefOperandIdx(Register Reg,const TargetRegisterInfo * TRI,bool isDead,bool Overlap) const1103 int MachineInstr::findRegisterDefOperandIdx(Register Reg,
1104                                             const TargetRegisterInfo *TRI,
1105                                             bool isDead, bool Overlap) const {
1106   bool isPhys = Reg.isPhysical();
1107   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
1108     const MachineOperand &MO = getOperand(i);
1109     // Accept regmask operands when Overlap is set.
1110     // Ignore them when looking for a specific def operand (Overlap == false).
1111     if (isPhys && Overlap && MO.isRegMask() && MO.clobbersPhysReg(Reg))
1112       return i;
1113     if (!MO.isReg() || !MO.isDef())
1114       continue;
1115     Register MOReg = MO.getReg();
1116     bool Found = (MOReg == Reg);
1117     if (!Found && TRI && isPhys && MOReg.isPhysical()) {
1118       if (Overlap)
1119         Found = TRI->regsOverlap(MOReg, Reg);
1120       else
1121         Found = TRI->isSubRegister(MOReg, Reg);
1122     }
1123     if (Found && (!isDead || MO.isDead()))
1124       return i;
1125   }
1126   return -1;
1127 }
1128 
1129 /// findFirstPredOperandIdx() - Find the index of the first operand in the
1130 /// operand list that is used to represent the predicate. It returns -1 if
1131 /// none is found.
findFirstPredOperandIdx() const1132 int MachineInstr::findFirstPredOperandIdx() const {
1133   // Don't call MCID.findFirstPredOperandIdx() because this variant
1134   // is sometimes called on an instruction that's not yet complete, and
1135   // so the number of operands is less than the MCID indicates. In
1136   // particular, the PTX target does this.
1137   const MCInstrDesc &MCID = getDesc();
1138   if (MCID.isPredicable()) {
1139     for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
1140       if (MCID.operands()[i].isPredicate())
1141         return i;
1142   }
1143 
1144   return -1;
1145 }
1146 
1147 // MachineOperand::TiedTo is 4 bits wide.
1148 const unsigned TiedMax = 15;
1149 
1150 /// tieOperands - Mark operands at DefIdx and UseIdx as tied to each other.
1151 ///
1152 /// Use and def operands can be tied together, indicated by a non-zero TiedTo
1153 /// field. TiedTo can have these values:
1154 ///
1155 /// 0:              Operand is not tied to anything.
1156 /// 1 to TiedMax-1: Tied to getOperand(TiedTo-1).
1157 /// TiedMax:        Tied to an operand >= TiedMax-1.
1158 ///
1159 /// The tied def must be one of the first TiedMax operands on a normal
1160 /// instruction. INLINEASM instructions allow more tied defs.
1161 ///
tieOperands(unsigned DefIdx,unsigned UseIdx)1162 void MachineInstr::tieOperands(unsigned DefIdx, unsigned UseIdx) {
1163   MachineOperand &DefMO = getOperand(DefIdx);
1164   MachineOperand &UseMO = getOperand(UseIdx);
1165   assert(DefMO.isDef() && "DefIdx must be a def operand");
1166   assert(UseMO.isUse() && "UseIdx must be a use operand");
1167   assert(!DefMO.isTied() && "Def is already tied to another use");
1168   assert(!UseMO.isTied() && "Use is already tied to another def");
1169 
1170   if (DefIdx < TiedMax)
1171     UseMO.TiedTo = DefIdx + 1;
1172   else {
1173     // Inline asm can use the group descriptors to find tied operands,
1174     // statepoint tied operands are trivial to match (1-1 reg def with reg use),
1175     // but on normal instruction, the tied def must be within the first TiedMax
1176     // operands.
1177     assert((isInlineAsm() || getOpcode() == TargetOpcode::STATEPOINT) &&
1178            "DefIdx out of range");
1179     UseMO.TiedTo = TiedMax;
1180   }
1181 
1182   // UseIdx can be out of range, we'll search for it in findTiedOperandIdx().
1183   DefMO.TiedTo = std::min(UseIdx + 1, TiedMax);
1184 }
1185 
1186 /// Given the index of a tied register operand, find the operand it is tied to.
1187 /// Defs are tied to uses and vice versa. Returns the index of the tied operand
1188 /// which must exist.
findTiedOperandIdx(unsigned OpIdx) const1189 unsigned MachineInstr::findTiedOperandIdx(unsigned OpIdx) const {
1190   const MachineOperand &MO = getOperand(OpIdx);
1191   assert(MO.isTied() && "Operand isn't tied");
1192 
1193   // Normally TiedTo is in range.
1194   if (MO.TiedTo < TiedMax)
1195     return MO.TiedTo - 1;
1196 
1197   // Uses on normal instructions can be out of range.
1198   if (!isInlineAsm() && getOpcode() != TargetOpcode::STATEPOINT) {
1199     // Normal tied defs must be in the 0..TiedMax-1 range.
1200     if (MO.isUse())
1201       return TiedMax - 1;
1202     // MO is a def. Search for the tied use.
1203     for (unsigned i = TiedMax - 1, e = getNumOperands(); i != e; ++i) {
1204       const MachineOperand &UseMO = getOperand(i);
1205       if (UseMO.isReg() && UseMO.isUse() && UseMO.TiedTo == OpIdx + 1)
1206         return i;
1207     }
1208     llvm_unreachable("Can't find tied use");
1209   }
1210 
1211   if (getOpcode() == TargetOpcode::STATEPOINT) {
1212     // In STATEPOINT defs correspond 1-1 to GC pointer operands passed
1213     // on registers.
1214     StatepointOpers SO(this);
1215     unsigned CurUseIdx = SO.getFirstGCPtrIdx();
1216     assert(CurUseIdx != -1U && "only gc pointer statepoint operands can be tied");
1217     unsigned NumDefs = getNumDefs();
1218     for (unsigned CurDefIdx = 0; CurDefIdx < NumDefs; ++CurDefIdx) {
1219       while (!getOperand(CurUseIdx).isReg())
1220         CurUseIdx = StackMaps::getNextMetaArgIdx(this, CurUseIdx);
1221       if (OpIdx == CurDefIdx)
1222         return CurUseIdx;
1223       if (OpIdx == CurUseIdx)
1224         return CurDefIdx;
1225       CurUseIdx = StackMaps::getNextMetaArgIdx(this, CurUseIdx);
1226     }
1227     llvm_unreachable("Can't find tied use");
1228   }
1229 
1230   // Now deal with inline asm by parsing the operand group descriptor flags.
1231   // Find the beginning of each operand group.
1232   SmallVector<unsigned, 8> GroupIdx;
1233   unsigned OpIdxGroup = ~0u;
1234   unsigned NumOps;
1235   for (unsigned i = InlineAsm::MIOp_FirstOperand, e = getNumOperands(); i < e;
1236        i += NumOps) {
1237     const MachineOperand &FlagMO = getOperand(i);
1238     assert(FlagMO.isImm() && "Invalid tied operand on inline asm");
1239     unsigned CurGroup = GroupIdx.size();
1240     GroupIdx.push_back(i);
1241     const InlineAsm::Flag F(FlagMO.getImm());
1242     NumOps = 1 + F.getNumOperandRegisters();
1243     // OpIdx belongs to this operand group.
1244     if (OpIdx > i && OpIdx < i + NumOps)
1245       OpIdxGroup = CurGroup;
1246     unsigned TiedGroup;
1247     if (!F.isUseOperandTiedToDef(TiedGroup))
1248       continue;
1249     // Operands in this group are tied to operands in TiedGroup which must be
1250     // earlier. Find the number of operands between the two groups.
1251     unsigned Delta = i - GroupIdx[TiedGroup];
1252 
1253     // OpIdx is a use tied to TiedGroup.
1254     if (OpIdxGroup == CurGroup)
1255       return OpIdx - Delta;
1256 
1257     // OpIdx is a def tied to this use group.
1258     if (OpIdxGroup == TiedGroup)
1259       return OpIdx + Delta;
1260   }
1261   llvm_unreachable("Invalid tied operand on inline asm");
1262 }
1263 
1264 /// clearKillInfo - Clears kill flags on all operands.
1265 ///
clearKillInfo()1266 void MachineInstr::clearKillInfo() {
1267   for (MachineOperand &MO : operands()) {
1268     if (MO.isReg() && MO.isUse())
1269       MO.setIsKill(false);
1270   }
1271 }
1272 
substituteRegister(Register FromReg,Register ToReg,unsigned SubIdx,const TargetRegisterInfo & RegInfo)1273 void MachineInstr::substituteRegister(Register FromReg, Register ToReg,
1274                                       unsigned SubIdx,
1275                                       const TargetRegisterInfo &RegInfo) {
1276   if (ToReg.isPhysical()) {
1277     if (SubIdx)
1278       ToReg = RegInfo.getSubReg(ToReg, SubIdx);
1279     for (MachineOperand &MO : operands()) {
1280       if (!MO.isReg() || MO.getReg() != FromReg)
1281         continue;
1282       MO.substPhysReg(ToReg, RegInfo);
1283     }
1284   } else {
1285     for (MachineOperand &MO : operands()) {
1286       if (!MO.isReg() || MO.getReg() != FromReg)
1287         continue;
1288       MO.substVirtReg(ToReg, SubIdx, RegInfo);
1289     }
1290   }
1291 }
1292 
1293 /// isSafeToMove - Return true if it is safe to move this instruction. If
1294 /// SawStore is set to true, it means that there is a store (or call) between
1295 /// the instruction's location and its intended destination.
isSafeToMove(AAResults * AA,bool & SawStore) const1296 bool MachineInstr::isSafeToMove(AAResults *AA, bool &SawStore) const {
1297   // Ignore stuff that we obviously can't move.
1298   //
1299   // Treat volatile loads as stores. This is not strictly necessary for
1300   // volatiles, but it is required for atomic loads. It is not allowed to move
1301   // a load across an atomic load with Ordering > Monotonic.
1302   if (mayStore() || isCall() || isPHI() ||
1303       (mayLoad() && hasOrderedMemoryRef())) {
1304     SawStore = true;
1305     return false;
1306   }
1307 
1308   if (isPosition() || isDebugInstr() || isTerminator() ||
1309       mayRaiseFPException() || hasUnmodeledSideEffects() ||
1310       isJumpTableDebugInfo())
1311     return false;
1312 
1313   // See if this instruction does a load.  If so, we have to guarantee that the
1314   // loaded value doesn't change between the load and the its intended
1315   // destination. The check for isInvariantLoad gives the target the chance to
1316   // classify the load as always returning a constant, e.g. a constant pool
1317   // load.
1318   if (mayLoad() && !isDereferenceableInvariantLoad())
1319     // Otherwise, this is a real load.  If there is a store between the load and
1320     // end of block, we can't move it.
1321     return !SawStore;
1322 
1323   return true;
1324 }
1325 
MemOperandsHaveAlias(const MachineFrameInfo & MFI,AAResults * AA,bool UseTBAA,const MachineMemOperand * MMOa,const MachineMemOperand * MMOb)1326 static bool MemOperandsHaveAlias(const MachineFrameInfo &MFI, AAResults *AA,
1327                                  bool UseTBAA, const MachineMemOperand *MMOa,
1328                                  const MachineMemOperand *MMOb) {
1329   // The following interface to AA is fashioned after DAGCombiner::isAlias and
1330   // operates with MachineMemOperand offset with some important assumptions:
1331   //   - LLVM fundamentally assumes flat address spaces.
1332   //   - MachineOperand offset can *only* result from legalization and cannot
1333   //     affect queries other than the trivial case of overlap checking.
1334   //   - These offsets never wrap and never step outside of allocated objects.
1335   //   - There should never be any negative offsets here.
1336   //
1337   // FIXME: Modify API to hide this math from "user"
1338   // Even before we go to AA we can reason locally about some memory objects. It
1339   // can save compile time, and possibly catch some corner cases not currently
1340   // covered.
1341 
1342   int64_t OffsetA = MMOa->getOffset();
1343   int64_t OffsetB = MMOb->getOffset();
1344   int64_t MinOffset = std::min(OffsetA, OffsetB);
1345 
1346   LocationSize WidthA = MMOa->getSize();
1347   LocationSize WidthB = MMOb->getSize();
1348   bool KnownWidthA = WidthA.hasValue();
1349   bool KnownWidthB = WidthB.hasValue();
1350   bool BothMMONonScalable = !WidthA.isScalable() && !WidthB.isScalable();
1351 
1352   const Value *ValA = MMOa->getValue();
1353   const Value *ValB = MMOb->getValue();
1354   bool SameVal = (ValA && ValB && (ValA == ValB));
1355   if (!SameVal) {
1356     const PseudoSourceValue *PSVa = MMOa->getPseudoValue();
1357     const PseudoSourceValue *PSVb = MMOb->getPseudoValue();
1358     if (PSVa && ValB && !PSVa->mayAlias(&MFI))
1359       return false;
1360     if (PSVb && ValA && !PSVb->mayAlias(&MFI))
1361       return false;
1362     if (PSVa && PSVb && (PSVa == PSVb))
1363       SameVal = true;
1364   }
1365 
1366   if (SameVal && BothMMONonScalable) {
1367     if (!KnownWidthA || !KnownWidthB)
1368       return true;
1369     int64_t MaxOffset = std::max(OffsetA, OffsetB);
1370     int64_t LowWidth = (MinOffset == OffsetA)
1371                            ? WidthA.getValue().getKnownMinValue()
1372                            : WidthB.getValue().getKnownMinValue();
1373     return (MinOffset + LowWidth > MaxOffset);
1374   }
1375 
1376   if (!AA)
1377     return true;
1378 
1379   if (!ValA || !ValB)
1380     return true;
1381 
1382   assert((OffsetA >= 0) && "Negative MachineMemOperand offset");
1383   assert((OffsetB >= 0) && "Negative MachineMemOperand offset");
1384 
1385   // If Scalable Location Size has non-zero offset, Width + Offset does not work
1386   // at the moment
1387   if ((WidthA.isScalable() && OffsetA > 0) ||
1388       (WidthB.isScalable() && OffsetB > 0))
1389     return true;
1390 
1391   int64_t OverlapA =
1392       KnownWidthA ? WidthA.getValue().getKnownMinValue() + OffsetA - MinOffset
1393                   : MemoryLocation::UnknownSize;
1394   int64_t OverlapB =
1395       KnownWidthB ? WidthB.getValue().getKnownMinValue() + OffsetB - MinOffset
1396                   : MemoryLocation::UnknownSize;
1397 
1398   LocationSize LocA = (WidthA.isScalable() || !KnownWidthA)
1399                           ? WidthA
1400                           : LocationSize::precise(OverlapA);
1401   LocationSize LocB = (WidthB.isScalable() || !KnownWidthB)
1402                           ? WidthB
1403                           : LocationSize::precise(OverlapB);
1404 
1405   return !AA->isNoAlias(
1406       MemoryLocation(ValA, LocA, UseTBAA ? MMOa->getAAInfo() : AAMDNodes()),
1407       MemoryLocation(ValB, LocB, UseTBAA ? MMOb->getAAInfo() : AAMDNodes()));
1408 }
1409 
mayAlias(AAResults * AA,const MachineInstr & Other,bool UseTBAA) const1410 bool MachineInstr::mayAlias(AAResults *AA, const MachineInstr &Other,
1411                             bool UseTBAA) const {
1412   const MachineFunction *MF = getMF();
1413   const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
1414   const MachineFrameInfo &MFI = MF->getFrameInfo();
1415 
1416   // Exclude call instruction which may alter the memory but can not be handled
1417   // by this function.
1418   if (isCall() || Other.isCall())
1419     return true;
1420 
1421   // If neither instruction stores to memory, they can't alias in any
1422   // meaningful way, even if they read from the same address.
1423   if (!mayStore() && !Other.mayStore())
1424     return false;
1425 
1426   // Both instructions must be memory operations to be able to alias.
1427   if (!mayLoadOrStore() || !Other.mayLoadOrStore())
1428     return false;
1429 
1430   // Let the target decide if memory accesses cannot possibly overlap.
1431   if (TII->areMemAccessesTriviallyDisjoint(*this, Other))
1432     return false;
1433 
1434   // Memory operations without memory operands may access anything. Be
1435   // conservative and assume `MayAlias`.
1436   if (memoperands_empty() || Other.memoperands_empty())
1437     return true;
1438 
1439   // Skip if there are too many memory operands.
1440   auto NumChecks = getNumMemOperands() * Other.getNumMemOperands();
1441   if (NumChecks > TII->getMemOperandAACheckLimit())
1442     return true;
1443 
1444   // Check each pair of memory operands from both instructions, which can't
1445   // alias only if all pairs won't alias.
1446   for (auto *MMOa : memoperands())
1447     for (auto *MMOb : Other.memoperands())
1448       if (MemOperandsHaveAlias(MFI, AA, UseTBAA, MMOa, MMOb))
1449         return true;
1450 
1451   return false;
1452 }
1453 
1454 /// hasOrderedMemoryRef - Return true if this instruction may have an ordered
1455 /// or volatile memory reference, or if the information describing the memory
1456 /// reference is not available. Return false if it is known to have no ordered
1457 /// memory references.
hasOrderedMemoryRef() const1458 bool MachineInstr::hasOrderedMemoryRef() const {
1459   // An instruction known never to access memory won't have a volatile access.
1460   if (!mayStore() &&
1461       !mayLoad() &&
1462       !isCall() &&
1463       !hasUnmodeledSideEffects())
1464     return false;
1465 
1466   // Otherwise, if the instruction has no memory reference information,
1467   // conservatively assume it wasn't preserved.
1468   if (memoperands_empty())
1469     return true;
1470 
1471   // Check if any of our memory operands are ordered.
1472   return llvm::any_of(memoperands(), [](const MachineMemOperand *MMO) {
1473     return !MMO->isUnordered();
1474   });
1475 }
1476 
1477 /// isDereferenceableInvariantLoad - Return true if this instruction will never
1478 /// trap and is loading from a location whose value is invariant across a run of
1479 /// this function.
isDereferenceableInvariantLoad() const1480 bool MachineInstr::isDereferenceableInvariantLoad() const {
1481   // If the instruction doesn't load at all, it isn't an invariant load.
1482   if (!mayLoad())
1483     return false;
1484 
1485   // If the instruction has lost its memoperands, conservatively assume that
1486   // it may not be an invariant load.
1487   if (memoperands_empty())
1488     return false;
1489 
1490   const MachineFrameInfo &MFI = getParent()->getParent()->getFrameInfo();
1491 
1492   for (MachineMemOperand *MMO : memoperands()) {
1493     if (!MMO->isUnordered())
1494       // If the memory operand has ordering side effects, we can't move the
1495       // instruction.  Such an instruction is technically an invariant load,
1496       // but the caller code would need updated to expect that.
1497       return false;
1498     if (MMO->isStore()) return false;
1499     if (MMO->isInvariant() && MMO->isDereferenceable())
1500       continue;
1501 
1502     // A load from a constant PseudoSourceValue is invariant.
1503     if (const PseudoSourceValue *PSV = MMO->getPseudoValue()) {
1504       if (PSV->isConstant(&MFI))
1505         continue;
1506     }
1507 
1508     // Otherwise assume conservatively.
1509     return false;
1510   }
1511 
1512   // Everything checks out.
1513   return true;
1514 }
1515 
1516 /// isConstantValuePHI - If the specified instruction is a PHI that always
1517 /// merges together the same virtual register, return the register, otherwise
1518 /// return 0.
isConstantValuePHI() const1519 unsigned MachineInstr::isConstantValuePHI() const {
1520   if (!isPHI())
1521     return 0;
1522   assert(getNumOperands() >= 3 &&
1523          "It's illegal to have a PHI without source operands");
1524 
1525   Register Reg = getOperand(1).getReg();
1526   for (unsigned i = 3, e = getNumOperands(); i < e; i += 2)
1527     if (getOperand(i).getReg() != Reg)
1528       return 0;
1529   return Reg;
1530 }
1531 
hasUnmodeledSideEffects() const1532 bool MachineInstr::hasUnmodeledSideEffects() const {
1533   if (hasProperty(MCID::UnmodeledSideEffects))
1534     return true;
1535   if (isInlineAsm()) {
1536     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1537     if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
1538       return true;
1539   }
1540 
1541   return false;
1542 }
1543 
isLoadFoldBarrier() const1544 bool MachineInstr::isLoadFoldBarrier() const {
1545   return mayStore() || isCall() ||
1546          (hasUnmodeledSideEffects() && !isPseudoProbe());
1547 }
1548 
1549 /// allDefsAreDead - Return true if all the defs of this instruction are dead.
1550 ///
allDefsAreDead() const1551 bool MachineInstr::allDefsAreDead() const {
1552   for (const MachineOperand &MO : operands()) {
1553     if (!MO.isReg() || MO.isUse())
1554       continue;
1555     if (!MO.isDead())
1556       return false;
1557   }
1558   return true;
1559 }
1560 
allImplicitDefsAreDead() const1561 bool MachineInstr::allImplicitDefsAreDead() const {
1562   for (const MachineOperand &MO : implicit_operands()) {
1563     if (!MO.isReg() || MO.isUse())
1564       continue;
1565     if (!MO.isDead())
1566       return false;
1567   }
1568   return true;
1569 }
1570 
1571 /// copyImplicitOps - Copy implicit register operands from specified
1572 /// instruction to this instruction.
copyImplicitOps(MachineFunction & MF,const MachineInstr & MI)1573 void MachineInstr::copyImplicitOps(MachineFunction &MF,
1574                                    const MachineInstr &MI) {
1575   for (const MachineOperand &MO :
1576        llvm::drop_begin(MI.operands(), MI.getDesc().getNumOperands()))
1577     if ((MO.isReg() && MO.isImplicit()) || MO.isRegMask())
1578       addOperand(MF, MO);
1579 }
1580 
hasComplexRegisterTies() const1581 bool MachineInstr::hasComplexRegisterTies() const {
1582   const MCInstrDesc &MCID = getDesc();
1583   if (MCID.Opcode == TargetOpcode::STATEPOINT)
1584     return true;
1585   for (unsigned I = 0, E = getNumOperands(); I < E; ++I) {
1586     const auto &Operand = getOperand(I);
1587     if (!Operand.isReg() || Operand.isDef())
1588       // Ignore the defined registers as MCID marks only the uses as tied.
1589       continue;
1590     int ExpectedTiedIdx = MCID.getOperandConstraint(I, MCOI::TIED_TO);
1591     int TiedIdx = Operand.isTied() ? int(findTiedOperandIdx(I)) : -1;
1592     if (ExpectedTiedIdx != TiedIdx)
1593       return true;
1594   }
1595   return false;
1596 }
1597 
getTypeToPrint(unsigned OpIdx,SmallBitVector & PrintedTypes,const MachineRegisterInfo & MRI) const1598 LLT MachineInstr::getTypeToPrint(unsigned OpIdx, SmallBitVector &PrintedTypes,
1599                                  const MachineRegisterInfo &MRI) const {
1600   const MachineOperand &Op = getOperand(OpIdx);
1601   if (!Op.isReg())
1602     return LLT{};
1603 
1604   if (isVariadic() || OpIdx >= getNumExplicitOperands())
1605     return MRI.getType(Op.getReg());
1606 
1607   auto &OpInfo = getDesc().operands()[OpIdx];
1608   if (!OpInfo.isGenericType())
1609     return MRI.getType(Op.getReg());
1610 
1611   if (PrintedTypes[OpInfo.getGenericTypeIndex()])
1612     return LLT{};
1613 
1614   LLT TypeToPrint = MRI.getType(Op.getReg());
1615   // Don't mark the type index printed if it wasn't actually printed: maybe
1616   // another operand with the same type index has an actual type attached:
1617   if (TypeToPrint.isValid())
1618     PrintedTypes.set(OpInfo.getGenericTypeIndex());
1619   return TypeToPrint;
1620 }
1621 
1622 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
dump() const1623 LLVM_DUMP_METHOD void MachineInstr::dump() const {
1624   dbgs() << "  ";
1625   print(dbgs());
1626 }
1627 
dumprImpl(const MachineRegisterInfo & MRI,unsigned Depth,unsigned MaxDepth,SmallPtrSetImpl<const MachineInstr * > & AlreadySeenInstrs) const1628 LLVM_DUMP_METHOD void MachineInstr::dumprImpl(
1629     const MachineRegisterInfo &MRI, unsigned Depth, unsigned MaxDepth,
1630     SmallPtrSetImpl<const MachineInstr *> &AlreadySeenInstrs) const {
1631   if (Depth >= MaxDepth)
1632     return;
1633   if (!AlreadySeenInstrs.insert(this).second)
1634     return;
1635   // PadToColumn always inserts at least one space.
1636   // Don't mess up the alignment if we don't want any space.
1637   if (Depth)
1638     fdbgs().PadToColumn(Depth * 2);
1639   print(fdbgs());
1640   for (const MachineOperand &MO : operands()) {
1641     if (!MO.isReg() || MO.isDef())
1642       continue;
1643     Register Reg = MO.getReg();
1644     if (Reg.isPhysical())
1645       continue;
1646     const MachineInstr *NewMI = MRI.getUniqueVRegDef(Reg);
1647     if (NewMI == nullptr)
1648       continue;
1649     NewMI->dumprImpl(MRI, Depth + 1, MaxDepth, AlreadySeenInstrs);
1650   }
1651 }
1652 
dumpr(const MachineRegisterInfo & MRI,unsigned MaxDepth) const1653 LLVM_DUMP_METHOD void MachineInstr::dumpr(const MachineRegisterInfo &MRI,
1654                                           unsigned MaxDepth) const {
1655   SmallPtrSet<const MachineInstr *, 16> AlreadySeenInstrs;
1656   dumprImpl(MRI, 0, MaxDepth, AlreadySeenInstrs);
1657 }
1658 #endif
1659 
print(raw_ostream & OS,bool IsStandalone,bool SkipOpers,bool SkipDebugLoc,bool AddNewLine,const TargetInstrInfo * TII) const1660 void MachineInstr::print(raw_ostream &OS, bool IsStandalone, bool SkipOpers,
1661                          bool SkipDebugLoc, bool AddNewLine,
1662                          const TargetInstrInfo *TII) const {
1663   const Module *M = nullptr;
1664   const Function *F = nullptr;
1665   if (const MachineFunction *MF = getMFIfAvailable(*this)) {
1666     F = &MF->getFunction();
1667     M = F->getParent();
1668     if (!TII)
1669       TII = MF->getSubtarget().getInstrInfo();
1670   }
1671 
1672   ModuleSlotTracker MST(M);
1673   if (F)
1674     MST.incorporateFunction(*F);
1675   print(OS, MST, IsStandalone, SkipOpers, SkipDebugLoc, AddNewLine, TII);
1676 }
1677 
print(raw_ostream & OS,ModuleSlotTracker & MST,bool IsStandalone,bool SkipOpers,bool SkipDebugLoc,bool AddNewLine,const TargetInstrInfo * TII) const1678 void MachineInstr::print(raw_ostream &OS, ModuleSlotTracker &MST,
1679                          bool IsStandalone, bool SkipOpers, bool SkipDebugLoc,
1680                          bool AddNewLine, const TargetInstrInfo *TII) const {
1681   // We can be a bit tidier if we know the MachineFunction.
1682   const TargetRegisterInfo *TRI = nullptr;
1683   const MachineRegisterInfo *MRI = nullptr;
1684   const TargetIntrinsicInfo *IntrinsicInfo = nullptr;
1685   tryToGetTargetInfo(*this, TRI, MRI, IntrinsicInfo, TII);
1686 
1687   if (isCFIInstruction())
1688     assert(getNumOperands() == 1 && "Expected 1 operand in CFI instruction");
1689 
1690   SmallBitVector PrintedTypes(8);
1691   bool ShouldPrintRegisterTies = IsStandalone || hasComplexRegisterTies();
1692   auto getTiedOperandIdx = [&](unsigned OpIdx) {
1693     if (!ShouldPrintRegisterTies)
1694       return 0U;
1695     const MachineOperand &MO = getOperand(OpIdx);
1696     if (MO.isReg() && MO.isTied() && !MO.isDef())
1697       return findTiedOperandIdx(OpIdx);
1698     return 0U;
1699   };
1700   unsigned StartOp = 0;
1701   unsigned e = getNumOperands();
1702 
1703   // Print explicitly defined operands on the left of an assignment syntax.
1704   while (StartOp < e) {
1705     const MachineOperand &MO = getOperand(StartOp);
1706     if (!MO.isReg() || !MO.isDef() || MO.isImplicit())
1707       break;
1708 
1709     if (StartOp != 0)
1710       OS << ", ";
1711 
1712     LLT TypeToPrint = MRI ? getTypeToPrint(StartOp, PrintedTypes, *MRI) : LLT{};
1713     unsigned TiedOperandIdx = getTiedOperandIdx(StartOp);
1714     MO.print(OS, MST, TypeToPrint, StartOp, /*PrintDef=*/false, IsStandalone,
1715              ShouldPrintRegisterTies, TiedOperandIdx, TRI, IntrinsicInfo);
1716     ++StartOp;
1717   }
1718 
1719   if (StartOp != 0)
1720     OS << " = ";
1721 
1722   if (getFlag(MachineInstr::FrameSetup))
1723     OS << "frame-setup ";
1724   if (getFlag(MachineInstr::FrameDestroy))
1725     OS << "frame-destroy ";
1726   if (getFlag(MachineInstr::FmNoNans))
1727     OS << "nnan ";
1728   if (getFlag(MachineInstr::FmNoInfs))
1729     OS << "ninf ";
1730   if (getFlag(MachineInstr::FmNsz))
1731     OS << "nsz ";
1732   if (getFlag(MachineInstr::FmArcp))
1733     OS << "arcp ";
1734   if (getFlag(MachineInstr::FmContract))
1735     OS << "contract ";
1736   if (getFlag(MachineInstr::FmAfn))
1737     OS << "afn ";
1738   if (getFlag(MachineInstr::FmReassoc))
1739     OS << "reassoc ";
1740   if (getFlag(MachineInstr::NoUWrap))
1741     OS << "nuw ";
1742   if (getFlag(MachineInstr::NoSWrap))
1743     OS << "nsw ";
1744   if (getFlag(MachineInstr::IsExact))
1745     OS << "exact ";
1746   if (getFlag(MachineInstr::NoFPExcept))
1747     OS << "nofpexcept ";
1748   if (getFlag(MachineInstr::NoMerge))
1749     OS << "nomerge ";
1750   if (getFlag(MachineInstr::NonNeg))
1751     OS << "nneg ";
1752   if (getFlag(MachineInstr::Disjoint))
1753     OS << "disjoint ";
1754 
1755   // Print the opcode name.
1756   if (TII)
1757     OS << TII->getName(getOpcode());
1758   else
1759     OS << "UNKNOWN";
1760 
1761   if (SkipOpers)
1762     return;
1763 
1764   // Print the rest of the operands.
1765   bool FirstOp = true;
1766   unsigned AsmDescOp = ~0u;
1767   unsigned AsmOpCount = 0;
1768 
1769   if (isInlineAsm() && e >= InlineAsm::MIOp_FirstOperand) {
1770     // Print asm string.
1771     OS << " ";
1772     const unsigned OpIdx = InlineAsm::MIOp_AsmString;
1773     LLT TypeToPrint = MRI ? getTypeToPrint(OpIdx, PrintedTypes, *MRI) : LLT{};
1774     unsigned TiedOperandIdx = getTiedOperandIdx(OpIdx);
1775     getOperand(OpIdx).print(OS, MST, TypeToPrint, OpIdx, /*PrintDef=*/true, IsStandalone,
1776                             ShouldPrintRegisterTies, TiedOperandIdx, TRI,
1777                             IntrinsicInfo);
1778 
1779     // Print HasSideEffects, MayLoad, MayStore, IsAlignStack
1780     unsigned ExtraInfo = getOperand(InlineAsm::MIOp_ExtraInfo).getImm();
1781     if (ExtraInfo & InlineAsm::Extra_HasSideEffects)
1782       OS << " [sideeffect]";
1783     if (ExtraInfo & InlineAsm::Extra_MayLoad)
1784       OS << " [mayload]";
1785     if (ExtraInfo & InlineAsm::Extra_MayStore)
1786       OS << " [maystore]";
1787     if (ExtraInfo & InlineAsm::Extra_IsConvergent)
1788       OS << " [isconvergent]";
1789     if (ExtraInfo & InlineAsm::Extra_IsAlignStack)
1790       OS << " [alignstack]";
1791     if (getInlineAsmDialect() == InlineAsm::AD_ATT)
1792       OS << " [attdialect]";
1793     if (getInlineAsmDialect() == InlineAsm::AD_Intel)
1794       OS << " [inteldialect]";
1795 
1796     StartOp = AsmDescOp = InlineAsm::MIOp_FirstOperand;
1797     FirstOp = false;
1798   }
1799 
1800   for (unsigned i = StartOp, e = getNumOperands(); i != e; ++i) {
1801     const MachineOperand &MO = getOperand(i);
1802 
1803     if (FirstOp) FirstOp = false; else OS << ",";
1804     OS << " ";
1805 
1806     if (isDebugValueLike() && MO.isMetadata()) {
1807       // Pretty print DBG_VALUE* instructions.
1808       auto *DIV = dyn_cast<DILocalVariable>(MO.getMetadata());
1809       if (DIV && !DIV->getName().empty())
1810         OS << "!\"" << DIV->getName() << '\"';
1811       else {
1812         LLT TypeToPrint = MRI ? getTypeToPrint(i, PrintedTypes, *MRI) : LLT{};
1813         unsigned TiedOperandIdx = getTiedOperandIdx(i);
1814         MO.print(OS, MST, TypeToPrint, i, /*PrintDef=*/true, IsStandalone,
1815                  ShouldPrintRegisterTies, TiedOperandIdx, TRI, IntrinsicInfo);
1816       }
1817     } else if (isDebugLabel() && MO.isMetadata()) {
1818       // Pretty print DBG_LABEL instructions.
1819       auto *DIL = dyn_cast<DILabel>(MO.getMetadata());
1820       if (DIL && !DIL->getName().empty())
1821         OS << "\"" << DIL->getName() << '\"';
1822       else {
1823         LLT TypeToPrint = MRI ? getTypeToPrint(i, PrintedTypes, *MRI) : LLT{};
1824         unsigned TiedOperandIdx = getTiedOperandIdx(i);
1825         MO.print(OS, MST, TypeToPrint, i, /*PrintDef=*/true, IsStandalone,
1826                  ShouldPrintRegisterTies, TiedOperandIdx, TRI, IntrinsicInfo);
1827       }
1828     } else if (i == AsmDescOp && MO.isImm()) {
1829       // Pretty print the inline asm operand descriptor.
1830       OS << '$' << AsmOpCount++;
1831       unsigned Flag = MO.getImm();
1832       const InlineAsm::Flag F(Flag);
1833       OS << ":[";
1834       OS << F.getKindName();
1835 
1836       unsigned RCID;
1837       if (!F.isImmKind() && !F.isMemKind() && F.hasRegClassConstraint(RCID)) {
1838         if (TRI) {
1839           OS << ':' << TRI->getRegClassName(TRI->getRegClass(RCID));
1840         } else
1841           OS << ":RC" << RCID;
1842       }
1843 
1844       if (F.isMemKind()) {
1845         const InlineAsm::ConstraintCode MCID = F.getMemoryConstraintID();
1846         OS << ":" << InlineAsm::getMemConstraintName(MCID);
1847       }
1848 
1849       unsigned TiedTo;
1850       if (F.isUseOperandTiedToDef(TiedTo))
1851         OS << " tiedto:$" << TiedTo;
1852 
1853       if ((F.isRegDefKind() || F.isRegDefEarlyClobberKind() ||
1854            F.isRegUseKind()) &&
1855           F.getRegMayBeFolded()) {
1856         OS << " foldable";
1857       }
1858 
1859       OS << ']';
1860 
1861       // Compute the index of the next operand descriptor.
1862       AsmDescOp += 1 + F.getNumOperandRegisters();
1863     } else {
1864       LLT TypeToPrint = MRI ? getTypeToPrint(i, PrintedTypes, *MRI) : LLT{};
1865       unsigned TiedOperandIdx = getTiedOperandIdx(i);
1866       if (MO.isImm() && isOperandSubregIdx(i))
1867         MachineOperand::printSubRegIdx(OS, MO.getImm(), TRI);
1868       else
1869         MO.print(OS, MST, TypeToPrint, i, /*PrintDef=*/true, IsStandalone,
1870                  ShouldPrintRegisterTies, TiedOperandIdx, TRI, IntrinsicInfo);
1871     }
1872   }
1873 
1874   // Print any optional symbols attached to this instruction as-if they were
1875   // operands.
1876   if (MCSymbol *PreInstrSymbol = getPreInstrSymbol()) {
1877     if (!FirstOp) {
1878       FirstOp = false;
1879       OS << ',';
1880     }
1881     OS << " pre-instr-symbol ";
1882     MachineOperand::printSymbol(OS, *PreInstrSymbol);
1883   }
1884   if (MCSymbol *PostInstrSymbol = getPostInstrSymbol()) {
1885     if (!FirstOp) {
1886       FirstOp = false;
1887       OS << ',';
1888     }
1889     OS << " post-instr-symbol ";
1890     MachineOperand::printSymbol(OS, *PostInstrSymbol);
1891   }
1892   if (MDNode *HeapAllocMarker = getHeapAllocMarker()) {
1893     if (!FirstOp) {
1894       FirstOp = false;
1895       OS << ',';
1896     }
1897     OS << " heap-alloc-marker ";
1898     HeapAllocMarker->printAsOperand(OS, MST);
1899   }
1900   if (MDNode *PCSections = getPCSections()) {
1901     if (!FirstOp) {
1902       FirstOp = false;
1903       OS << ',';
1904     }
1905     OS << " pcsections ";
1906     PCSections->printAsOperand(OS, MST);
1907   }
1908   if (MDNode *MMRA = getMMRAMetadata()) {
1909     if (!FirstOp) {
1910       FirstOp = false;
1911       OS << ',';
1912     }
1913     OS << " mmra ";
1914     MMRA->printAsOperand(OS, MST);
1915   }
1916   if (uint32_t CFIType = getCFIType()) {
1917     if (!FirstOp)
1918       OS << ',';
1919     OS << " cfi-type " << CFIType;
1920   }
1921 
1922   if (DebugInstrNum) {
1923     if (!FirstOp)
1924       OS << ",";
1925     OS << " debug-instr-number " << DebugInstrNum;
1926   }
1927 
1928   if (!SkipDebugLoc) {
1929     if (const DebugLoc &DL = getDebugLoc()) {
1930       if (!FirstOp)
1931         OS << ',';
1932       OS << " debug-location ";
1933       DL->printAsOperand(OS, MST);
1934     }
1935   }
1936 
1937   if (!memoperands_empty()) {
1938     SmallVector<StringRef, 0> SSNs;
1939     const LLVMContext *Context = nullptr;
1940     std::unique_ptr<LLVMContext> CtxPtr;
1941     const MachineFrameInfo *MFI = nullptr;
1942     if (const MachineFunction *MF = getMFIfAvailable(*this)) {
1943       MFI = &MF->getFrameInfo();
1944       Context = &MF->getFunction().getContext();
1945     } else {
1946       CtxPtr = std::make_unique<LLVMContext>();
1947       Context = CtxPtr.get();
1948     }
1949 
1950     OS << " :: ";
1951     bool NeedComma = false;
1952     for (const MachineMemOperand *Op : memoperands()) {
1953       if (NeedComma)
1954         OS << ", ";
1955       Op->print(OS, MST, SSNs, *Context, MFI, TII);
1956       NeedComma = true;
1957     }
1958   }
1959 
1960   if (SkipDebugLoc)
1961     return;
1962 
1963   bool HaveSemi = false;
1964 
1965   // Print debug location information.
1966   if (const DebugLoc &DL = getDebugLoc()) {
1967     if (!HaveSemi) {
1968       OS << ';';
1969       HaveSemi = true;
1970     }
1971     OS << ' ';
1972     DL.print(OS);
1973   }
1974 
1975   // Print extra comments for DEBUG_VALUE and friends if they are well-formed.
1976   if ((isNonListDebugValue() && getNumOperands() >= 4) ||
1977       (isDebugValueList() && getNumOperands() >= 2) ||
1978       (isDebugRef() && getNumOperands() >= 3)) {
1979     if (getDebugVariableOp().isMetadata()) {
1980       if (!HaveSemi) {
1981         OS << ";";
1982         HaveSemi = true;
1983       }
1984       auto *DV = getDebugVariable();
1985       OS << " line no:" << DV->getLine();
1986       if (isIndirectDebugValue())
1987         OS << " indirect";
1988     }
1989   }
1990   // TODO: DBG_LABEL
1991 
1992   if (AddNewLine)
1993     OS << '\n';
1994 }
1995 
addRegisterKilled(Register IncomingReg,const TargetRegisterInfo * RegInfo,bool AddIfNotFound)1996 bool MachineInstr::addRegisterKilled(Register IncomingReg,
1997                                      const TargetRegisterInfo *RegInfo,
1998                                      bool AddIfNotFound) {
1999   bool isPhysReg = IncomingReg.isPhysical();
2000   bool hasAliases = isPhysReg &&
2001     MCRegAliasIterator(IncomingReg, RegInfo, false).isValid();
2002   bool Found = false;
2003   SmallVector<unsigned,4> DeadOps;
2004   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
2005     MachineOperand &MO = getOperand(i);
2006     if (!MO.isReg() || !MO.isUse() || MO.isUndef())
2007       continue;
2008 
2009     // DEBUG_VALUE nodes do not contribute to code generation and should
2010     // always be ignored. Failure to do so may result in trying to modify
2011     // KILL flags on DEBUG_VALUE nodes.
2012     if (MO.isDebug())
2013       continue;
2014 
2015     Register Reg = MO.getReg();
2016     if (!Reg)
2017       continue;
2018 
2019     if (Reg == IncomingReg) {
2020       if (!Found) {
2021         if (MO.isKill())
2022           // The register is already marked kill.
2023           return true;
2024         if (isPhysReg && isRegTiedToDefOperand(i))
2025           // Two-address uses of physregs must not be marked kill.
2026           return true;
2027         MO.setIsKill();
2028         Found = true;
2029       }
2030     } else if (hasAliases && MO.isKill() && Reg.isPhysical()) {
2031       // A super-register kill already exists.
2032       if (RegInfo->isSuperRegister(IncomingReg, Reg))
2033         return true;
2034       if (RegInfo->isSubRegister(IncomingReg, Reg))
2035         DeadOps.push_back(i);
2036     }
2037   }
2038 
2039   // Trim unneeded kill operands.
2040   while (!DeadOps.empty()) {
2041     unsigned OpIdx = DeadOps.back();
2042     if (getOperand(OpIdx).isImplicit() &&
2043         (!isInlineAsm() || findInlineAsmFlagIdx(OpIdx) < 0))
2044       removeOperand(OpIdx);
2045     else
2046       getOperand(OpIdx).setIsKill(false);
2047     DeadOps.pop_back();
2048   }
2049 
2050   // If not found, this means an alias of one of the operands is killed. Add a
2051   // new implicit operand if required.
2052   if (!Found && AddIfNotFound) {
2053     addOperand(MachineOperand::CreateReg(IncomingReg,
2054                                          false /*IsDef*/,
2055                                          true  /*IsImp*/,
2056                                          true  /*IsKill*/));
2057     return true;
2058   }
2059   return Found;
2060 }
2061 
clearRegisterKills(Register Reg,const TargetRegisterInfo * RegInfo)2062 void MachineInstr::clearRegisterKills(Register Reg,
2063                                       const TargetRegisterInfo *RegInfo) {
2064   if (!Reg.isPhysical())
2065     RegInfo = nullptr;
2066   for (MachineOperand &MO : operands()) {
2067     if (!MO.isReg() || !MO.isUse() || !MO.isKill())
2068       continue;
2069     Register OpReg = MO.getReg();
2070     if ((RegInfo && RegInfo->regsOverlap(Reg, OpReg)) || Reg == OpReg)
2071       MO.setIsKill(false);
2072   }
2073 }
2074 
addRegisterDead(Register Reg,const TargetRegisterInfo * RegInfo,bool AddIfNotFound)2075 bool MachineInstr::addRegisterDead(Register Reg,
2076                                    const TargetRegisterInfo *RegInfo,
2077                                    bool AddIfNotFound) {
2078   bool isPhysReg = Reg.isPhysical();
2079   bool hasAliases = isPhysReg &&
2080     MCRegAliasIterator(Reg, RegInfo, false).isValid();
2081   bool Found = false;
2082   SmallVector<unsigned,4> DeadOps;
2083   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
2084     MachineOperand &MO = getOperand(i);
2085     if (!MO.isReg() || !MO.isDef())
2086       continue;
2087     Register MOReg = MO.getReg();
2088     if (!MOReg)
2089       continue;
2090 
2091     if (MOReg == Reg) {
2092       MO.setIsDead();
2093       Found = true;
2094     } else if (hasAliases && MO.isDead() && MOReg.isPhysical()) {
2095       // There exists a super-register that's marked dead.
2096       if (RegInfo->isSuperRegister(Reg, MOReg))
2097         return true;
2098       if (RegInfo->isSubRegister(Reg, MOReg))
2099         DeadOps.push_back(i);
2100     }
2101   }
2102 
2103   // Trim unneeded dead operands.
2104   while (!DeadOps.empty()) {
2105     unsigned OpIdx = DeadOps.back();
2106     if (getOperand(OpIdx).isImplicit() &&
2107         (!isInlineAsm() || findInlineAsmFlagIdx(OpIdx) < 0))
2108       removeOperand(OpIdx);
2109     else
2110       getOperand(OpIdx).setIsDead(false);
2111     DeadOps.pop_back();
2112   }
2113 
2114   // If not found, this means an alias of one of the operands is dead. Add a
2115   // new implicit operand if required.
2116   if (Found || !AddIfNotFound)
2117     return Found;
2118 
2119   addOperand(MachineOperand::CreateReg(Reg,
2120                                        true  /*IsDef*/,
2121                                        true  /*IsImp*/,
2122                                        false /*IsKill*/,
2123                                        true  /*IsDead*/));
2124   return true;
2125 }
2126 
clearRegisterDeads(Register Reg)2127 void MachineInstr::clearRegisterDeads(Register Reg) {
2128   for (MachineOperand &MO : operands()) {
2129     if (!MO.isReg() || !MO.isDef() || MO.getReg() != Reg)
2130       continue;
2131     MO.setIsDead(false);
2132   }
2133 }
2134 
setRegisterDefReadUndef(Register Reg,bool IsUndef)2135 void MachineInstr::setRegisterDefReadUndef(Register Reg, bool IsUndef) {
2136   for (MachineOperand &MO : operands()) {
2137     if (!MO.isReg() || !MO.isDef() || MO.getReg() != Reg || MO.getSubReg() == 0)
2138       continue;
2139     MO.setIsUndef(IsUndef);
2140   }
2141 }
2142 
addRegisterDefined(Register Reg,const TargetRegisterInfo * RegInfo)2143 void MachineInstr::addRegisterDefined(Register Reg,
2144                                       const TargetRegisterInfo *RegInfo) {
2145   if (Reg.isPhysical()) {
2146     MachineOperand *MO = findRegisterDefOperand(Reg, RegInfo, false, false);
2147     if (MO)
2148       return;
2149   } else {
2150     for (const MachineOperand &MO : operands()) {
2151       if (MO.isReg() && MO.getReg() == Reg && MO.isDef() &&
2152           MO.getSubReg() == 0)
2153         return;
2154     }
2155   }
2156   addOperand(MachineOperand::CreateReg(Reg,
2157                                        true  /*IsDef*/,
2158                                        true  /*IsImp*/));
2159 }
2160 
setPhysRegsDeadExcept(ArrayRef<Register> UsedRegs,const TargetRegisterInfo & TRI)2161 void MachineInstr::setPhysRegsDeadExcept(ArrayRef<Register> UsedRegs,
2162                                          const TargetRegisterInfo &TRI) {
2163   bool HasRegMask = false;
2164   for (MachineOperand &MO : operands()) {
2165     if (MO.isRegMask()) {
2166       HasRegMask = true;
2167       continue;
2168     }
2169     if (!MO.isReg() || !MO.isDef()) continue;
2170     Register Reg = MO.getReg();
2171     if (!Reg.isPhysical())
2172       continue;
2173     // If there are no uses, including partial uses, the def is dead.
2174     if (llvm::none_of(UsedRegs,
2175                       [&](MCRegister Use) { return TRI.regsOverlap(Use, Reg); }))
2176       MO.setIsDead();
2177   }
2178 
2179   // This is a call with a register mask operand.
2180   // Mask clobbers are always dead, so add defs for the non-dead defines.
2181   if (HasRegMask)
2182     for (const Register &UsedReg : UsedRegs)
2183       addRegisterDefined(UsedReg, &TRI);
2184 }
2185 
2186 unsigned
getHashValue(const MachineInstr * const & MI)2187 MachineInstrExpressionTrait::getHashValue(const MachineInstr* const &MI) {
2188   // Build up a buffer of hash code components.
2189   SmallVector<size_t, 16> HashComponents;
2190   HashComponents.reserve(MI->getNumOperands() + 1);
2191   HashComponents.push_back(MI->getOpcode());
2192   for (const MachineOperand &MO : MI->operands()) {
2193     if (MO.isReg() && MO.isDef() && MO.getReg().isVirtual())
2194       continue;  // Skip virtual register defs.
2195 
2196     HashComponents.push_back(hash_value(MO));
2197   }
2198   return hash_combine_range(HashComponents.begin(), HashComponents.end());
2199 }
2200 
emitError(StringRef Msg) const2201 void MachineInstr::emitError(StringRef Msg) const {
2202   // Find the source location cookie.
2203   uint64_t LocCookie = 0;
2204   const MDNode *LocMD = nullptr;
2205   for (unsigned i = getNumOperands(); i != 0; --i) {
2206     if (getOperand(i-1).isMetadata() &&
2207         (LocMD = getOperand(i-1).getMetadata()) &&
2208         LocMD->getNumOperands() != 0) {
2209       if (const ConstantInt *CI =
2210               mdconst::dyn_extract<ConstantInt>(LocMD->getOperand(0))) {
2211         LocCookie = CI->getZExtValue();
2212         break;
2213       }
2214     }
2215   }
2216 
2217   if (const MachineBasicBlock *MBB = getParent())
2218     if (const MachineFunction *MF = MBB->getParent())
2219       return MF->getFunction().getContext().emitError(LocCookie, Msg);
2220   report_fatal_error(Msg);
2221 }
2222 
BuildMI(MachineFunction & MF,const DebugLoc & DL,const MCInstrDesc & MCID,bool IsIndirect,Register Reg,const MDNode * Variable,const MDNode * Expr)2223 MachineInstrBuilder llvm::BuildMI(MachineFunction &MF, const DebugLoc &DL,
2224                                   const MCInstrDesc &MCID, bool IsIndirect,
2225                                   Register Reg, const MDNode *Variable,
2226                                   const MDNode *Expr) {
2227   assert(isa<DILocalVariable>(Variable) && "not a variable");
2228   assert(cast<DIExpression>(Expr)->isValid() && "not an expression");
2229   assert(cast<DILocalVariable>(Variable)->isValidLocationForIntrinsic(DL) &&
2230          "Expected inlined-at fields to agree");
2231   auto MIB = BuildMI(MF, DL, MCID).addReg(Reg);
2232   if (IsIndirect)
2233     MIB.addImm(0U);
2234   else
2235     MIB.addReg(0U);
2236   return MIB.addMetadata(Variable).addMetadata(Expr);
2237 }
2238 
BuildMI(MachineFunction & MF,const DebugLoc & DL,const MCInstrDesc & MCID,bool IsIndirect,ArrayRef<MachineOperand> DebugOps,const MDNode * Variable,const MDNode * Expr)2239 MachineInstrBuilder llvm::BuildMI(MachineFunction &MF, const DebugLoc &DL,
2240                                   const MCInstrDesc &MCID, bool IsIndirect,
2241                                   ArrayRef<MachineOperand> DebugOps,
2242                                   const MDNode *Variable, const MDNode *Expr) {
2243   assert(isa<DILocalVariable>(Variable) && "not a variable");
2244   assert(cast<DIExpression>(Expr)->isValid() && "not an expression");
2245   assert(cast<DILocalVariable>(Variable)->isValidLocationForIntrinsic(DL) &&
2246          "Expected inlined-at fields to agree");
2247   if (MCID.Opcode == TargetOpcode::DBG_VALUE) {
2248     assert(DebugOps.size() == 1 &&
2249            "DBG_VALUE must contain exactly one debug operand");
2250     MachineOperand DebugOp = DebugOps[0];
2251     if (DebugOp.isReg())
2252       return BuildMI(MF, DL, MCID, IsIndirect, DebugOp.getReg(), Variable,
2253                      Expr);
2254 
2255     auto MIB = BuildMI(MF, DL, MCID).add(DebugOp);
2256     if (IsIndirect)
2257       MIB.addImm(0U);
2258     else
2259       MIB.addReg(0U);
2260     return MIB.addMetadata(Variable).addMetadata(Expr);
2261   }
2262 
2263   auto MIB = BuildMI(MF, DL, MCID);
2264   MIB.addMetadata(Variable).addMetadata(Expr);
2265   for (const MachineOperand &DebugOp : DebugOps)
2266     if (DebugOp.isReg())
2267       MIB.addReg(DebugOp.getReg());
2268     else
2269       MIB.add(DebugOp);
2270   return MIB;
2271 }
2272 
BuildMI(MachineBasicBlock & BB,MachineBasicBlock::iterator I,const DebugLoc & DL,const MCInstrDesc & MCID,bool IsIndirect,Register Reg,const MDNode * Variable,const MDNode * Expr)2273 MachineInstrBuilder llvm::BuildMI(MachineBasicBlock &BB,
2274                                   MachineBasicBlock::iterator I,
2275                                   const DebugLoc &DL, const MCInstrDesc &MCID,
2276                                   bool IsIndirect, Register Reg,
2277                                   const MDNode *Variable, const MDNode *Expr) {
2278   MachineFunction &MF = *BB.getParent();
2279   MachineInstr *MI = BuildMI(MF, DL, MCID, IsIndirect, Reg, Variable, Expr);
2280   BB.insert(I, MI);
2281   return MachineInstrBuilder(MF, MI);
2282 }
2283 
BuildMI(MachineBasicBlock & BB,MachineBasicBlock::iterator I,const DebugLoc & DL,const MCInstrDesc & MCID,bool IsIndirect,ArrayRef<MachineOperand> DebugOps,const MDNode * Variable,const MDNode * Expr)2284 MachineInstrBuilder llvm::BuildMI(MachineBasicBlock &BB,
2285                                   MachineBasicBlock::iterator I,
2286                                   const DebugLoc &DL, const MCInstrDesc &MCID,
2287                                   bool IsIndirect,
2288                                   ArrayRef<MachineOperand> DebugOps,
2289                                   const MDNode *Variable, const MDNode *Expr) {
2290   MachineFunction &MF = *BB.getParent();
2291   MachineInstr *MI =
2292       BuildMI(MF, DL, MCID, IsIndirect, DebugOps, Variable, Expr);
2293   BB.insert(I, MI);
2294   return MachineInstrBuilder(MF, *MI);
2295 }
2296 
2297 /// Compute the new DIExpression to use with a DBG_VALUE for a spill slot.
2298 /// This prepends DW_OP_deref when spilling an indirect DBG_VALUE.
2299 static const DIExpression *
computeExprForSpill(const MachineInstr & MI,SmallVectorImpl<const MachineOperand * > & SpilledOperands)2300 computeExprForSpill(const MachineInstr &MI,
2301                     SmallVectorImpl<const MachineOperand *> &SpilledOperands) {
2302   assert(MI.getDebugVariable()->isValidLocationForIntrinsic(MI.getDebugLoc()) &&
2303          "Expected inlined-at fields to agree");
2304 
2305   const DIExpression *Expr = MI.getDebugExpression();
2306   if (MI.isIndirectDebugValue()) {
2307     assert(MI.getDebugOffset().getImm() == 0 &&
2308            "DBG_VALUE with nonzero offset");
2309     Expr = DIExpression::prepend(Expr, DIExpression::DerefBefore);
2310   } else if (MI.isDebugValueList()) {
2311     // We will replace the spilled register with a frame index, so
2312     // immediately deref all references to the spilled register.
2313     std::array<uint64_t, 1> Ops{{dwarf::DW_OP_deref}};
2314     for (const MachineOperand *Op : SpilledOperands) {
2315       unsigned OpIdx = MI.getDebugOperandIndex(Op);
2316       Expr = DIExpression::appendOpsToArg(Expr, Ops, OpIdx);
2317     }
2318   }
2319   return Expr;
2320 }
computeExprForSpill(const MachineInstr & MI,Register SpillReg)2321 static const DIExpression *computeExprForSpill(const MachineInstr &MI,
2322                                                Register SpillReg) {
2323   assert(MI.hasDebugOperandForReg(SpillReg) && "Spill Reg is not used in MI.");
2324   SmallVector<const MachineOperand *> SpillOperands;
2325   for (const MachineOperand &Op : MI.getDebugOperandsForReg(SpillReg))
2326     SpillOperands.push_back(&Op);
2327   return computeExprForSpill(MI, SpillOperands);
2328 }
2329 
buildDbgValueForSpill(MachineBasicBlock & BB,MachineBasicBlock::iterator I,const MachineInstr & Orig,int FrameIndex,Register SpillReg)2330 MachineInstr *llvm::buildDbgValueForSpill(MachineBasicBlock &BB,
2331                                           MachineBasicBlock::iterator I,
2332                                           const MachineInstr &Orig,
2333                                           int FrameIndex, Register SpillReg) {
2334   assert(!Orig.isDebugRef() &&
2335          "DBG_INSTR_REF should not reference a virtual register.");
2336   const DIExpression *Expr = computeExprForSpill(Orig, SpillReg);
2337   MachineInstrBuilder NewMI =
2338       BuildMI(BB, I, Orig.getDebugLoc(), Orig.getDesc());
2339   // Non-Variadic Operands: Location, Offset, Variable, Expression
2340   // Variadic Operands:     Variable, Expression, Locations...
2341   if (Orig.isNonListDebugValue())
2342     NewMI.addFrameIndex(FrameIndex).addImm(0U);
2343   NewMI.addMetadata(Orig.getDebugVariable()).addMetadata(Expr);
2344   if (Orig.isDebugValueList()) {
2345     for (const MachineOperand &Op : Orig.debug_operands())
2346       if (Op.isReg() && Op.getReg() == SpillReg)
2347         NewMI.addFrameIndex(FrameIndex);
2348       else
2349         NewMI.add(MachineOperand(Op));
2350   }
2351   return NewMI;
2352 }
buildDbgValueForSpill(MachineBasicBlock & BB,MachineBasicBlock::iterator I,const MachineInstr & Orig,int FrameIndex,SmallVectorImpl<const MachineOperand * > & SpilledOperands)2353 MachineInstr *llvm::buildDbgValueForSpill(
2354     MachineBasicBlock &BB, MachineBasicBlock::iterator I,
2355     const MachineInstr &Orig, int FrameIndex,
2356     SmallVectorImpl<const MachineOperand *> &SpilledOperands) {
2357   const DIExpression *Expr = computeExprForSpill(Orig, SpilledOperands);
2358   MachineInstrBuilder NewMI =
2359       BuildMI(BB, I, Orig.getDebugLoc(), Orig.getDesc());
2360   // Non-Variadic Operands: Location, Offset, Variable, Expression
2361   // Variadic Operands:     Variable, Expression, Locations...
2362   if (Orig.isNonListDebugValue())
2363     NewMI.addFrameIndex(FrameIndex).addImm(0U);
2364   NewMI.addMetadata(Orig.getDebugVariable()).addMetadata(Expr);
2365   if (Orig.isDebugValueList()) {
2366     for (const MachineOperand &Op : Orig.debug_operands())
2367       if (is_contained(SpilledOperands, &Op))
2368         NewMI.addFrameIndex(FrameIndex);
2369       else
2370         NewMI.add(MachineOperand(Op));
2371   }
2372   return NewMI;
2373 }
2374 
updateDbgValueForSpill(MachineInstr & Orig,int FrameIndex,Register Reg)2375 void llvm::updateDbgValueForSpill(MachineInstr &Orig, int FrameIndex,
2376                                   Register Reg) {
2377   const DIExpression *Expr = computeExprForSpill(Orig, Reg);
2378   if (Orig.isNonListDebugValue())
2379     Orig.getDebugOffset().ChangeToImmediate(0U);
2380   for (MachineOperand &Op : Orig.getDebugOperandsForReg(Reg))
2381     Op.ChangeToFrameIndex(FrameIndex);
2382   Orig.getDebugExpressionOp().setMetadata(Expr);
2383 }
2384 
collectDebugValues(SmallVectorImpl<MachineInstr * > & DbgValues)2385 void MachineInstr::collectDebugValues(
2386                                 SmallVectorImpl<MachineInstr *> &DbgValues) {
2387   MachineInstr &MI = *this;
2388   if (!MI.getOperand(0).isReg())
2389     return;
2390 
2391   MachineBasicBlock::iterator DI = MI; ++DI;
2392   for (MachineBasicBlock::iterator DE = MI.getParent()->end();
2393        DI != DE; ++DI) {
2394     if (!DI->isDebugValue())
2395       return;
2396     if (DI->hasDebugOperandForReg(MI.getOperand(0).getReg()))
2397       DbgValues.push_back(&*DI);
2398   }
2399 }
2400 
changeDebugValuesDefReg(Register Reg)2401 void MachineInstr::changeDebugValuesDefReg(Register Reg) {
2402   // Collect matching debug values.
2403   SmallVector<MachineInstr *, 2> DbgValues;
2404 
2405   if (!getOperand(0).isReg())
2406     return;
2407 
2408   Register DefReg = getOperand(0).getReg();
2409   auto *MRI = getRegInfo();
2410   for (auto &MO : MRI->use_operands(DefReg)) {
2411     auto *DI = MO.getParent();
2412     if (!DI->isDebugValue())
2413       continue;
2414     if (DI->hasDebugOperandForReg(DefReg)) {
2415       DbgValues.push_back(DI);
2416     }
2417   }
2418 
2419   // Propagate Reg to debug value instructions.
2420   for (auto *DBI : DbgValues)
2421     for (MachineOperand &Op : DBI->getDebugOperandsForReg(DefReg))
2422       Op.setReg(Reg);
2423 }
2424 
2425 using MMOList = SmallVector<const MachineMemOperand *, 2>;
2426 
getSpillSlotSize(const MMOList & Accesses,const MachineFrameInfo & MFI)2427 static LocationSize getSpillSlotSize(const MMOList &Accesses,
2428                                      const MachineFrameInfo &MFI) {
2429   uint64_t Size = 0;
2430   for (const auto *A : Accesses) {
2431     if (MFI.isSpillSlotObjectIndex(
2432             cast<FixedStackPseudoSourceValue>(A->getPseudoValue())
2433                 ->getFrameIndex())) {
2434       LocationSize S = A->getSize();
2435       if (!S.hasValue())
2436         return LocationSize::beforeOrAfterPointer();
2437       Size += S.getValue();
2438     }
2439   }
2440   return Size;
2441 }
2442 
2443 std::optional<LocationSize>
getSpillSize(const TargetInstrInfo * TII) const2444 MachineInstr::getSpillSize(const TargetInstrInfo *TII) const {
2445   int FI;
2446   if (TII->isStoreToStackSlotPostFE(*this, FI)) {
2447     const MachineFrameInfo &MFI = getMF()->getFrameInfo();
2448     if (MFI.isSpillSlotObjectIndex(FI))
2449       return (*memoperands_begin())->getSize();
2450   }
2451   return std::nullopt;
2452 }
2453 
2454 std::optional<LocationSize>
getFoldedSpillSize(const TargetInstrInfo * TII) const2455 MachineInstr::getFoldedSpillSize(const TargetInstrInfo *TII) const {
2456   MMOList Accesses;
2457   if (TII->hasStoreToStackSlot(*this, Accesses))
2458     return getSpillSlotSize(Accesses, getMF()->getFrameInfo());
2459   return std::nullopt;
2460 }
2461 
2462 std::optional<LocationSize>
getRestoreSize(const TargetInstrInfo * TII) const2463 MachineInstr::getRestoreSize(const TargetInstrInfo *TII) const {
2464   int FI;
2465   if (TII->isLoadFromStackSlotPostFE(*this, FI)) {
2466     const MachineFrameInfo &MFI = getMF()->getFrameInfo();
2467     if (MFI.isSpillSlotObjectIndex(FI))
2468       return (*memoperands_begin())->getSize();
2469   }
2470   return std::nullopt;
2471 }
2472 
2473 std::optional<LocationSize>
getFoldedRestoreSize(const TargetInstrInfo * TII) const2474 MachineInstr::getFoldedRestoreSize(const TargetInstrInfo *TII) const {
2475   MMOList Accesses;
2476   if (TII->hasLoadFromStackSlot(*this, Accesses))
2477     return getSpillSlotSize(Accesses, getMF()->getFrameInfo());
2478   return std::nullopt;
2479 }
2480 
getDebugInstrNum()2481 unsigned MachineInstr::getDebugInstrNum() {
2482   if (DebugInstrNum == 0)
2483     DebugInstrNum = getParent()->getParent()->getNewDebugInstrNum();
2484   return DebugInstrNum;
2485 }
2486 
getDebugInstrNum(MachineFunction & MF)2487 unsigned MachineInstr::getDebugInstrNum(MachineFunction &MF) {
2488   if (DebugInstrNum == 0)
2489     DebugInstrNum = MF.getNewDebugInstrNum();
2490   return DebugInstrNum;
2491 }
2492 
getFirst2LLTs() const2493 std::tuple<LLT, LLT> MachineInstr::getFirst2LLTs() const {
2494   return std::tuple(getRegInfo()->getType(getOperand(0).getReg()),
2495                     getRegInfo()->getType(getOperand(1).getReg()));
2496 }
2497 
getFirst3LLTs() const2498 std::tuple<LLT, LLT, LLT> MachineInstr::getFirst3LLTs() const {
2499   return std::tuple(getRegInfo()->getType(getOperand(0).getReg()),
2500                     getRegInfo()->getType(getOperand(1).getReg()),
2501                     getRegInfo()->getType(getOperand(2).getReg()));
2502 }
2503 
getFirst4LLTs() const2504 std::tuple<LLT, LLT, LLT, LLT> MachineInstr::getFirst4LLTs() const {
2505   return std::tuple(getRegInfo()->getType(getOperand(0).getReg()),
2506                     getRegInfo()->getType(getOperand(1).getReg()),
2507                     getRegInfo()->getType(getOperand(2).getReg()),
2508                     getRegInfo()->getType(getOperand(3).getReg()));
2509 }
2510 
getFirst5LLTs() const2511 std::tuple<LLT, LLT, LLT, LLT, LLT> MachineInstr::getFirst5LLTs() const {
2512   return std::tuple(getRegInfo()->getType(getOperand(0).getReg()),
2513                     getRegInfo()->getType(getOperand(1).getReg()),
2514                     getRegInfo()->getType(getOperand(2).getReg()),
2515                     getRegInfo()->getType(getOperand(3).getReg()),
2516                     getRegInfo()->getType(getOperand(4).getReg()));
2517 }
2518 
2519 std::tuple<Register, LLT, Register, LLT>
getFirst2RegLLTs() const2520 MachineInstr::getFirst2RegLLTs() const {
2521   Register Reg0 = getOperand(0).getReg();
2522   Register Reg1 = getOperand(1).getReg();
2523   return std::tuple(Reg0, getRegInfo()->getType(Reg0), Reg1,
2524                     getRegInfo()->getType(Reg1));
2525 }
2526 
2527 std::tuple<Register, LLT, Register, LLT, Register, LLT>
getFirst3RegLLTs() const2528 MachineInstr::getFirst3RegLLTs() const {
2529   Register Reg0 = getOperand(0).getReg();
2530   Register Reg1 = getOperand(1).getReg();
2531   Register Reg2 = getOperand(2).getReg();
2532   return std::tuple(Reg0, getRegInfo()->getType(Reg0), Reg1,
2533                     getRegInfo()->getType(Reg1), Reg2,
2534                     getRegInfo()->getType(Reg2));
2535 }
2536 
2537 std::tuple<Register, LLT, Register, LLT, Register, LLT, Register, LLT>
getFirst4RegLLTs() const2538 MachineInstr::getFirst4RegLLTs() const {
2539   Register Reg0 = getOperand(0).getReg();
2540   Register Reg1 = getOperand(1).getReg();
2541   Register Reg2 = getOperand(2).getReg();
2542   Register Reg3 = getOperand(3).getReg();
2543   return std::tuple(
2544       Reg0, getRegInfo()->getType(Reg0), Reg1, getRegInfo()->getType(Reg1),
2545       Reg2, getRegInfo()->getType(Reg2), Reg3, getRegInfo()->getType(Reg3));
2546 }
2547 
2548 std::tuple<Register, LLT, Register, LLT, Register, LLT, Register, LLT, Register,
2549            LLT>
getFirst5RegLLTs() const2550 MachineInstr::getFirst5RegLLTs() const {
2551   Register Reg0 = getOperand(0).getReg();
2552   Register Reg1 = getOperand(1).getReg();
2553   Register Reg2 = getOperand(2).getReg();
2554   Register Reg3 = getOperand(3).getReg();
2555   Register Reg4 = getOperand(4).getReg();
2556   return std::tuple(
2557       Reg0, getRegInfo()->getType(Reg0), Reg1, getRegInfo()->getType(Reg1),
2558       Reg2, getRegInfo()->getType(Reg2), Reg3, getRegInfo()->getType(Reg3),
2559       Reg4, getRegInfo()->getType(Reg4));
2560 }
2561 
insert(mop_iterator InsertBefore,ArrayRef<MachineOperand> Ops)2562 void MachineInstr::insert(mop_iterator InsertBefore,
2563                           ArrayRef<MachineOperand> Ops) {
2564   assert(InsertBefore != nullptr && "invalid iterator");
2565   assert(InsertBefore->getParent() == this &&
2566          "iterator points to operand of other inst");
2567   if (Ops.empty())
2568     return;
2569 
2570   // Do one pass to untie operands.
2571   SmallDenseMap<unsigned, unsigned> TiedOpIndices;
2572   for (const MachineOperand &MO : operands()) {
2573     if (MO.isReg() && MO.isTied()) {
2574       unsigned OpNo = getOperandNo(&MO);
2575       unsigned TiedTo = findTiedOperandIdx(OpNo);
2576       TiedOpIndices[OpNo] = TiedTo;
2577       untieRegOperand(OpNo);
2578     }
2579   }
2580 
2581   unsigned OpIdx = getOperandNo(InsertBefore);
2582   unsigned NumOperands = getNumOperands();
2583   unsigned OpsToMove = NumOperands - OpIdx;
2584 
2585   SmallVector<MachineOperand> MovingOps;
2586   MovingOps.reserve(OpsToMove);
2587 
2588   for (unsigned I = 0; I < OpsToMove; ++I) {
2589     MovingOps.emplace_back(getOperand(OpIdx));
2590     removeOperand(OpIdx);
2591   }
2592   for (const MachineOperand &MO : Ops)
2593     addOperand(MO);
2594   for (const MachineOperand &OpMoved : MovingOps)
2595     addOperand(OpMoved);
2596 
2597   // Re-tie operands.
2598   for (auto [Tie1, Tie2] : TiedOpIndices) {
2599     if (Tie1 >= OpIdx)
2600       Tie1 += Ops.size();
2601     if (Tie2 >= OpIdx)
2602       Tie2 += Ops.size();
2603     tieOperands(Tie1, Tie2);
2604   }
2605 }
2606 
mayFoldInlineAsmRegOp(unsigned OpId) const2607 bool MachineInstr::mayFoldInlineAsmRegOp(unsigned OpId) const {
2608   assert(OpId && "expected non-zero operand id");
2609   assert(isInlineAsm() && "should only be used on inline asm");
2610 
2611   if (!getOperand(OpId).isReg())
2612     return false;
2613 
2614   const MachineOperand &MD = getOperand(OpId - 1);
2615   if (!MD.isImm())
2616     return false;
2617 
2618   InlineAsm::Flag F(MD.getImm());
2619   if (F.isRegUseKind() || F.isRegDefKind() || F.isRegDefEarlyClobberKind())
2620     return F.getRegMayBeFolded();
2621   return false;
2622 }
2623