1 //===-- MachineVerifier.cpp - Machine Code Verifier -----------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Pass to verify generated machine code. The following is checked:
12 // Operand counts: All explicit operands must be present.
14 // Register classes: All physical and virtual register operands must be
15 // compatible with the register class required by the instruction descriptor.
17 // Register live intervals: Registers must be defined only once, and must be
18 // defined before use.
20 // The machine code verifier is enabled from LLVMTargetMachine.cpp with the
21 // command-line option -verify-machineinstrs, or by defining the environment
22 // variable LLVM_VERIFY_MACHINEINSTRS to the name of a file that will receive
23 // the verifier errors.
24 //===----------------------------------------------------------------------===//
26 #include "llvm/ADT/DenseSet.h"
27 #include "llvm/ADT/DepthFirstIterator.h"
28 #include "llvm/ADT/SetOperations.h"
29 #include "llvm/ADT/SmallVector.h"
30 #include "llvm/Analysis/EHPersonalities.h"
31 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
32 #include "llvm/CodeGen/LiveStackAnalysis.h"
33 #include "llvm/CodeGen/LiveVariables.h"
34 #include "llvm/CodeGen/MachineFrameInfo.h"
35 #include "llvm/CodeGen/MachineFunctionPass.h"
36 #include "llvm/CodeGen/MachineMemOperand.h"
37 #include "llvm/CodeGen/MachineRegisterInfo.h"
38 #include "llvm/CodeGen/Passes.h"
39 #include "llvm/CodeGen/StackMaps.h"
40 #include "llvm/IR/BasicBlock.h"
41 #include "llvm/IR/InlineAsm.h"
42 #include "llvm/IR/Instructions.h"
43 #include "llvm/MC/MCAsmInfo.h"
44 #include "llvm/Support/Debug.h"
45 #include "llvm/Support/ErrorHandling.h"
46 #include "llvm/Support/FileSystem.h"
47 #include "llvm/Support/raw_ostream.h"
48 #include "llvm/Target/TargetInstrInfo.h"
49 #include "llvm/Target/TargetMachine.h"
50 #include "llvm/Target/TargetRegisterInfo.h"
51 #include "llvm/Target/TargetSubtargetInfo.h"
55 struct MachineVerifier {
57 MachineVerifier(Pass *pass, const char *b) :
62 unsigned verify(MachineFunction &MF);
66 const MachineFunction *MF;
67 const TargetMachine *TM;
68 const TargetInstrInfo *TII;
69 const TargetRegisterInfo *TRI;
70 const MachineRegisterInfo *MRI;
74 // Avoid querying the MachineFunctionProperties for each operand.
75 bool isFunctionRegBankSelected;
76 bool isFunctionSelected;
78 typedef SmallVector<unsigned, 16> RegVector;
79 typedef SmallVector<const uint32_t*, 4> RegMaskVector;
80 typedef DenseSet<unsigned> RegSet;
81 typedef DenseMap<unsigned, const MachineInstr*> RegMap;
82 typedef SmallPtrSet<const MachineBasicBlock*, 8> BlockSet;
84 const MachineInstr *FirstTerminator;
85 BlockSet FunctionBlocks;
87 BitVector regsReserved;
89 RegVector regsDefined, regsDead, regsKilled;
90 RegMaskVector regMasks;
94 // Add Reg and any sub-registers to RV
95 void addRegWithSubRegs(RegVector &RV, unsigned Reg) {
97 if (TargetRegisterInfo::isPhysicalRegister(Reg))
98 for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs)
99 RV.push_back(*SubRegs);
103 // Is this MBB reachable from the MF entry point?
106 // Vregs that must be live in because they are used without being
107 // defined. Map value is the user.
110 // Regs killed in MBB. They may be defined again, and will then be in both
111 // regsKilled and regsLiveOut.
114 // Regs defined in MBB and live out. Note that vregs passing through may
115 // be live out without being mentioned here.
118 // Vregs that pass through MBB untouched. This set is disjoint from
119 // regsKilled and regsLiveOut.
122 // Vregs that must pass through MBB because they are needed by a successor
123 // block. This set is disjoint from regsLiveOut.
124 RegSet vregsRequired;
126 // Set versions of block's predecessor and successor lists.
127 BlockSet Preds, Succs;
129 BBInfo() : reachable(false) {}
131 // Add register to vregsPassed if it belongs there. Return true if
133 bool addPassed(unsigned Reg) {
134 if (!TargetRegisterInfo::isVirtualRegister(Reg))
136 if (regsKilled.count(Reg) || regsLiveOut.count(Reg))
138 return vregsPassed.insert(Reg).second;
141 // Same for a full set.
142 bool addPassed(const RegSet &RS) {
143 bool changed = false;
144 for (RegSet::const_iterator I = RS.begin(), E = RS.end(); I != E; ++I)
150 // Add register to vregsRequired if it belongs there. Return true if
152 bool addRequired(unsigned Reg) {
153 if (!TargetRegisterInfo::isVirtualRegister(Reg))
155 if (regsLiveOut.count(Reg))
157 return vregsRequired.insert(Reg).second;
160 // Same for a full set.
161 bool addRequired(const RegSet &RS) {
162 bool changed = false;
163 for (RegSet::const_iterator I = RS.begin(), E = RS.end(); I != E; ++I)
169 // Same for a full map.
170 bool addRequired(const RegMap &RM) {
171 bool changed = false;
172 for (RegMap::const_iterator I = RM.begin(), E = RM.end(); I != E; ++I)
173 if (addRequired(I->first))
178 // Live-out registers are either in regsLiveOut or vregsPassed.
179 bool isLiveOut(unsigned Reg) const {
180 return regsLiveOut.count(Reg) || vregsPassed.count(Reg);
184 // Extra register info per MBB.
185 DenseMap<const MachineBasicBlock*, BBInfo> MBBInfoMap;
187 bool isReserved(unsigned Reg) {
188 return Reg < regsReserved.size() && regsReserved.test(Reg);
191 bool isAllocatable(unsigned Reg) const {
192 return Reg < TRI->getNumRegs() && TRI->isInAllocatableClass(Reg) &&
193 !regsReserved.test(Reg);
196 // Analysis information if available
197 LiveVariables *LiveVars;
198 LiveIntervals *LiveInts;
199 LiveStacks *LiveStks;
200 SlotIndexes *Indexes;
202 void visitMachineFunctionBefore();
203 void visitMachineBasicBlockBefore(const MachineBasicBlock *MBB);
204 void visitMachineBundleBefore(const MachineInstr *MI);
205 void visitMachineInstrBefore(const MachineInstr *MI);
206 void visitMachineOperand(const MachineOperand *MO, unsigned MONum);
207 void visitMachineInstrAfter(const MachineInstr *MI);
208 void visitMachineBundleAfter(const MachineInstr *MI);
209 void visitMachineBasicBlockAfter(const MachineBasicBlock *MBB);
210 void visitMachineFunctionAfter();
212 void report(const char *msg, const MachineFunction *MF);
213 void report(const char *msg, const MachineBasicBlock *MBB);
214 void report(const char *msg, const MachineInstr *MI);
215 void report(const char *msg, const MachineOperand *MO, unsigned MONum);
217 void report_context(const LiveInterval &LI) const;
218 void report_context(const LiveRange &LR, unsigned VRegUnit,
219 LaneBitmask LaneMask) const;
220 void report_context(const LiveRange::Segment &S) const;
221 void report_context(const VNInfo &VNI) const;
222 void report_context(SlotIndex Pos) const;
223 void report_context_liverange(const LiveRange &LR) const;
224 void report_context_lanemask(LaneBitmask LaneMask) const;
225 void report_context_vreg(unsigned VReg) const;
226 void report_context_vreg_regunit(unsigned VRegOrRegUnit) const;
228 void verifyInlineAsm(const MachineInstr *MI);
230 void checkLiveness(const MachineOperand *MO, unsigned MONum);
231 void checkLivenessAtUse(const MachineOperand *MO, unsigned MONum,
232 SlotIndex UseIdx, const LiveRange &LR, unsigned Reg,
233 LaneBitmask LaneMask = LaneBitmask::getNone());
234 void checkLivenessAtDef(const MachineOperand *MO, unsigned MONum,
235 SlotIndex DefIdx, const LiveRange &LR, unsigned Reg,
236 LaneBitmask LaneMask = LaneBitmask::getNone());
238 void markReachable(const MachineBasicBlock *MBB);
239 void calcRegsPassed();
240 void checkPHIOps(const MachineBasicBlock *MBB);
242 void calcRegsRequired();
243 void verifyLiveVariables();
244 void verifyLiveIntervals();
245 void verifyLiveInterval(const LiveInterval&);
246 void verifyLiveRangeValue(const LiveRange&, const VNInfo*, unsigned,
248 void verifyLiveRangeSegment(const LiveRange&,
249 const LiveRange::const_iterator I, unsigned,
251 void verifyLiveRange(const LiveRange&, unsigned,
252 LaneBitmask LaneMask = LaneBitmask::getNone());
254 void verifyStackFrame();
256 void verifySlotIndexes() const;
257 void verifyProperties(const MachineFunction &MF);
260 struct MachineVerifierPass : public MachineFunctionPass {
261 static char ID; // Pass ID, replacement for typeid
262 const std::string Banner;
264 MachineVerifierPass(std::string banner = std::string())
265 : MachineFunctionPass(ID), Banner(std::move(banner)) {
266 initializeMachineVerifierPassPass(*PassRegistry::getPassRegistry());
269 void getAnalysisUsage(AnalysisUsage &AU) const override {
270 AU.setPreservesAll();
271 MachineFunctionPass::getAnalysisUsage(AU);
274 bool runOnMachineFunction(MachineFunction &MF) override {
275 unsigned FoundErrors = MachineVerifier(this, Banner.c_str()).verify(MF);
277 report_fatal_error("Found "+Twine(FoundErrors)+" machine code errors.");
284 char MachineVerifierPass::ID = 0;
285 INITIALIZE_PASS(MachineVerifierPass, "machineverifier",
286 "Verify generated machine code", false, false)
288 FunctionPass *llvm::createMachineVerifierPass(const std::string &Banner) {
289 return new MachineVerifierPass(Banner);
292 bool MachineFunction::verify(Pass *p, const char *Banner, bool AbortOnErrors)
294 MachineFunction &MF = const_cast<MachineFunction&>(*this);
295 unsigned FoundErrors = MachineVerifier(p, Banner).verify(MF);
296 if (AbortOnErrors && FoundErrors)
297 report_fatal_error("Found "+Twine(FoundErrors)+" machine code errors.");
298 return FoundErrors == 0;
301 void MachineVerifier::verifySlotIndexes() const {
302 if (Indexes == nullptr)
305 // Ensure the IdxMBB list is sorted by slot indexes.
307 for (SlotIndexes::MBBIndexIterator I = Indexes->MBBIndexBegin(),
308 E = Indexes->MBBIndexEnd(); I != E; ++I) {
309 assert(!Last.isValid() || I->first > Last);
314 void MachineVerifier::verifyProperties(const MachineFunction &MF) {
315 // If a pass has introduced virtual registers without clearing the
316 // NoVRegs property (or set it without allocating the vregs)
317 // then report an error.
318 if (MF.getProperties().hasProperty(
319 MachineFunctionProperties::Property::NoVRegs) &&
320 MRI->getNumVirtRegs())
321 report("Function has NoVRegs property but there are VReg operands", &MF);
324 unsigned MachineVerifier::verify(MachineFunction &MF) {
328 TM = &MF.getTarget();
329 TII = MF.getSubtarget().getInstrInfo();
330 TRI = MF.getSubtarget().getRegisterInfo();
331 MRI = &MF.getRegInfo();
333 isFunctionRegBankSelected = MF.getProperties().hasProperty(
334 MachineFunctionProperties::Property::RegBankSelected);
335 isFunctionSelected = MF.getProperties().hasProperty(
336 MachineFunctionProperties::Property::Selected);
343 LiveInts = PASS->getAnalysisIfAvailable<LiveIntervals>();
344 // We don't want to verify LiveVariables if LiveIntervals is available.
346 LiveVars = PASS->getAnalysisIfAvailable<LiveVariables>();
347 LiveStks = PASS->getAnalysisIfAvailable<LiveStacks>();
348 Indexes = PASS->getAnalysisIfAvailable<SlotIndexes>();
353 verifyProperties(MF);
355 visitMachineFunctionBefore();
356 for (MachineFunction::const_iterator MFI = MF.begin(), MFE = MF.end();
358 visitMachineBasicBlockBefore(&*MFI);
359 // Keep track of the current bundle header.
360 const MachineInstr *CurBundle = nullptr;
361 // Do we expect the next instruction to be part of the same bundle?
362 bool InBundle = false;
364 for (MachineBasicBlock::const_instr_iterator MBBI = MFI->instr_begin(),
365 MBBE = MFI->instr_end(); MBBI != MBBE; ++MBBI) {
366 if (MBBI->getParent() != &*MFI) {
367 report("Bad instruction parent pointer", &*MFI);
368 errs() << "Instruction: " << *MBBI;
372 // Check for consistent bundle flags.
373 if (InBundle && !MBBI->isBundledWithPred())
374 report("Missing BundledPred flag, "
375 "BundledSucc was set on predecessor",
377 if (!InBundle && MBBI->isBundledWithPred())
378 report("BundledPred flag is set, "
379 "but BundledSucc not set on predecessor",
382 // Is this a bundle header?
383 if (!MBBI->isInsideBundle()) {
385 visitMachineBundleAfter(CurBundle);
387 visitMachineBundleBefore(CurBundle);
388 } else if (!CurBundle)
389 report("No bundle header", &*MBBI);
390 visitMachineInstrBefore(&*MBBI);
391 for (unsigned I = 0, E = MBBI->getNumOperands(); I != E; ++I) {
392 const MachineInstr &MI = *MBBI;
393 const MachineOperand &Op = MI.getOperand(I);
394 if (Op.getParent() != &MI) {
395 // Make sure to use correct addOperand / RemoveOperand / ChangeTo
396 // functions when replacing operands of a MachineInstr.
397 report("Instruction has operand with wrong parent set", &MI);
400 visitMachineOperand(&Op, I);
403 visitMachineInstrAfter(&*MBBI);
405 // Was this the last bundled instruction?
406 InBundle = MBBI->isBundledWithSucc();
409 visitMachineBundleAfter(CurBundle);
411 report("BundledSucc flag set on last instruction in block", &MFI->back());
412 visitMachineBasicBlockAfter(&*MFI);
414 visitMachineFunctionAfter();
427 void MachineVerifier::report(const char *msg, const MachineFunction *MF) {
430 if (!foundErrors++) {
432 errs() << "# " << Banner << '\n';
433 if (LiveInts != nullptr)
434 LiveInts->print(errs());
436 MF->print(errs(), Indexes);
438 errs() << "*** Bad machine code: " << msg << " ***\n"
439 << "- function: " << MF->getName() << "\n";
442 void MachineVerifier::report(const char *msg, const MachineBasicBlock *MBB) {
444 report(msg, MBB->getParent());
445 errs() << "- basic block: BB#" << MBB->getNumber()
446 << ' ' << MBB->getName()
447 << " (" << (const void*)MBB << ')';
449 errs() << " [" << Indexes->getMBBStartIdx(MBB)
450 << ';' << Indexes->getMBBEndIdx(MBB) << ')';
454 void MachineVerifier::report(const char *msg, const MachineInstr *MI) {
456 report(msg, MI->getParent());
457 errs() << "- instruction: ";
458 if (Indexes && Indexes->hasIndex(*MI))
459 errs() << Indexes->getInstructionIndex(*MI) << '\t';
460 MI->print(errs(), /*SkipOpers=*/true);
464 void MachineVerifier::report(const char *msg,
465 const MachineOperand *MO, unsigned MONum) {
467 report(msg, MO->getParent());
468 errs() << "- operand " << MONum << ": ";
469 MO->print(errs(), TRI);
473 void MachineVerifier::report_context(SlotIndex Pos) const {
474 errs() << "- at: " << Pos << '\n';
477 void MachineVerifier::report_context(const LiveInterval &LI) const {
478 errs() << "- interval: " << LI << '\n';
481 void MachineVerifier::report_context(const LiveRange &LR, unsigned VRegUnit,
482 LaneBitmask LaneMask) const {
483 report_context_liverange(LR);
484 report_context_vreg_regunit(VRegUnit);
486 report_context_lanemask(LaneMask);
489 void MachineVerifier::report_context(const LiveRange::Segment &S) const {
490 errs() << "- segment: " << S << '\n';
493 void MachineVerifier::report_context(const VNInfo &VNI) const {
494 errs() << "- ValNo: " << VNI.id << " (def " << VNI.def << ")\n";
497 void MachineVerifier::report_context_liverange(const LiveRange &LR) const {
498 errs() << "- liverange: " << LR << '\n';
501 void MachineVerifier::report_context_vreg(unsigned VReg) const {
502 errs() << "- v. register: " << PrintReg(VReg, TRI) << '\n';
505 void MachineVerifier::report_context_vreg_regunit(unsigned VRegOrUnit) const {
506 if (TargetRegisterInfo::isVirtualRegister(VRegOrUnit)) {
507 report_context_vreg(VRegOrUnit);
509 errs() << "- regunit: " << PrintRegUnit(VRegOrUnit, TRI) << '\n';
513 void MachineVerifier::report_context_lanemask(LaneBitmask LaneMask) const {
514 errs() << "- lanemask: " << PrintLaneMask(LaneMask) << '\n';
517 void MachineVerifier::markReachable(const MachineBasicBlock *MBB) {
518 BBInfo &MInfo = MBBInfoMap[MBB];
519 if (!MInfo.reachable) {
520 MInfo.reachable = true;
521 for (MachineBasicBlock::const_succ_iterator SuI = MBB->succ_begin(),
522 SuE = MBB->succ_end(); SuI != SuE; ++SuI)
527 void MachineVerifier::visitMachineFunctionBefore() {
528 lastIndex = SlotIndex();
529 regsReserved = MRI->reservedRegsFrozen() ? MRI->getReservedRegs()
530 : TRI->getReservedRegs(*MF);
533 markReachable(&MF->front());
535 // Build a set of the basic blocks in the function.
536 FunctionBlocks.clear();
537 for (const auto &MBB : *MF) {
538 FunctionBlocks.insert(&MBB);
539 BBInfo &MInfo = MBBInfoMap[&MBB];
541 MInfo.Preds.insert(MBB.pred_begin(), MBB.pred_end());
542 if (MInfo.Preds.size() != MBB.pred_size())
543 report("MBB has duplicate entries in its predecessor list.", &MBB);
545 MInfo.Succs.insert(MBB.succ_begin(), MBB.succ_end());
546 if (MInfo.Succs.size() != MBB.succ_size())
547 report("MBB has duplicate entries in its successor list.", &MBB);
550 // Check that the register use lists are sane.
551 MRI->verifyUseLists();
557 // Does iterator point to a and b as the first two elements?
558 static bool matchPair(MachineBasicBlock::const_succ_iterator i,
559 const MachineBasicBlock *a, const MachineBasicBlock *b) {
568 MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
569 FirstTerminator = nullptr;
571 if (!MF->getProperties().hasProperty(
572 MachineFunctionProperties::Property::NoPHIs) && MRI->tracksLiveness()) {
573 // If this block has allocatable physical registers live-in, check that
574 // it is an entry block or landing pad.
575 for (const auto &LI : MBB->liveins()) {
576 if (isAllocatable(LI.PhysReg) && !MBB->isEHPad() &&
577 MBB->getIterator() != MBB->getParent()->begin()) {
578 report("MBB has allocatable live-in, but isn't entry or landing-pad.", MBB);
583 // Count the number of landing pad successors.
584 SmallPtrSet<MachineBasicBlock*, 4> LandingPadSuccs;
585 for (MachineBasicBlock::const_succ_iterator I = MBB->succ_begin(),
586 E = MBB->succ_end(); I != E; ++I) {
588 LandingPadSuccs.insert(*I);
589 if (!FunctionBlocks.count(*I))
590 report("MBB has successor that isn't part of the function.", MBB);
591 if (!MBBInfoMap[*I].Preds.count(MBB)) {
592 report("Inconsistent CFG", MBB);
593 errs() << "MBB is not in the predecessor list of the successor BB#"
594 << (*I)->getNumber() << ".\n";
598 // Check the predecessor list.
599 for (MachineBasicBlock::const_pred_iterator I = MBB->pred_begin(),
600 E = MBB->pred_end(); I != E; ++I) {
601 if (!FunctionBlocks.count(*I))
602 report("MBB has predecessor that isn't part of the function.", MBB);
603 if (!MBBInfoMap[*I].Succs.count(MBB)) {
604 report("Inconsistent CFG", MBB);
605 errs() << "MBB is not in the successor list of the predecessor BB#"
606 << (*I)->getNumber() << ".\n";
610 const MCAsmInfo *AsmInfo = TM->getMCAsmInfo();
611 const BasicBlock *BB = MBB->getBasicBlock();
612 const Function *Fn = MF->getFunction();
613 if (LandingPadSuccs.size() > 1 &&
615 AsmInfo->getExceptionHandlingType() == ExceptionHandling::SjLj &&
616 BB && isa<SwitchInst>(BB->getTerminator())) &&
617 !isFuncletEHPersonality(classifyEHPersonality(Fn->getPersonalityFn())))
618 report("MBB has more than one landing pad successor", MBB);
620 // Call AnalyzeBranch. If it succeeds, there several more conditions to check.
621 MachineBasicBlock *TBB = nullptr, *FBB = nullptr;
622 SmallVector<MachineOperand, 4> Cond;
623 if (!TII->analyzeBranch(*const_cast<MachineBasicBlock *>(MBB), TBB, FBB,
625 // Ok, AnalyzeBranch thinks it knows what's going on with this block. Let's
626 // check whether its answers match up with reality.
628 // Block falls through to its successor.
629 MachineFunction::const_iterator MBBI = MBB->getIterator();
631 if (MBBI == MF->end()) {
632 // It's possible that the block legitimately ends with a noreturn
633 // call or an unreachable, in which case it won't actually fall
634 // out the bottom of the function.
635 } else if (MBB->succ_size() == LandingPadSuccs.size()) {
636 // It's possible that the block legitimately ends with a noreturn
637 // call or an unreachable, in which case it won't actuall fall
639 } else if (MBB->succ_size() != 1+LandingPadSuccs.size()) {
640 report("MBB exits via unconditional fall-through but doesn't have "
641 "exactly one CFG successor!", MBB);
642 } else if (!MBB->isSuccessor(&*MBBI)) {
643 report("MBB exits via unconditional fall-through but its successor "
644 "differs from its CFG successor!", MBB);
646 if (!MBB->empty() && MBB->back().isBarrier() &&
647 !TII->isPredicated(MBB->back())) {
648 report("MBB exits via unconditional fall-through but ends with a "
649 "barrier instruction!", MBB);
652 report("MBB exits via unconditional fall-through but has a condition!",
655 } else if (TBB && !FBB && Cond.empty()) {
656 // Block unconditionally branches somewhere.
657 // If the block has exactly one successor, that happens to be a
658 // landingpad, accept it as valid control flow.
659 if (MBB->succ_size() != 1+LandingPadSuccs.size() &&
660 (MBB->succ_size() != 1 || LandingPadSuccs.size() != 1 ||
661 *MBB->succ_begin() != *LandingPadSuccs.begin())) {
662 report("MBB exits via unconditional branch but doesn't have "
663 "exactly one CFG successor!", MBB);
664 } else if (!MBB->isSuccessor(TBB)) {
665 report("MBB exits via unconditional branch but the CFG "
666 "successor doesn't match the actual successor!", MBB);
669 report("MBB exits via unconditional branch but doesn't contain "
670 "any instructions!", MBB);
671 } else if (!MBB->back().isBarrier()) {
672 report("MBB exits via unconditional branch but doesn't end with a "
673 "barrier instruction!", MBB);
674 } else if (!MBB->back().isTerminator()) {
675 report("MBB exits via unconditional branch but the branch isn't a "
676 "terminator instruction!", MBB);
678 } else if (TBB && !FBB && !Cond.empty()) {
679 // Block conditionally branches somewhere, otherwise falls through.
680 MachineFunction::const_iterator MBBI = MBB->getIterator();
682 if (MBBI == MF->end()) {
683 report("MBB conditionally falls through out of function!", MBB);
684 } else if (MBB->succ_size() == 1) {
685 // A conditional branch with only one successor is weird, but allowed.
687 report("MBB exits via conditional branch/fall-through but only has "
688 "one CFG successor!", MBB);
689 else if (TBB != *MBB->succ_begin())
690 report("MBB exits via conditional branch/fall-through but the CFG "
691 "successor don't match the actual successor!", MBB);
692 } else if (MBB->succ_size() != 2) {
693 report("MBB exits via conditional branch/fall-through but doesn't have "
694 "exactly two CFG successors!", MBB);
695 } else if (!matchPair(MBB->succ_begin(), TBB, &*MBBI)) {
696 report("MBB exits via conditional branch/fall-through but the CFG "
697 "successors don't match the actual successors!", MBB);
700 report("MBB exits via conditional branch/fall-through but doesn't "
701 "contain any instructions!", MBB);
702 } else if (MBB->back().isBarrier()) {
703 report("MBB exits via conditional branch/fall-through but ends with a "
704 "barrier instruction!", MBB);
705 } else if (!MBB->back().isTerminator()) {
706 report("MBB exits via conditional branch/fall-through but the branch "
707 "isn't a terminator instruction!", MBB);
709 } else if (TBB && FBB) {
710 // Block conditionally branches somewhere, otherwise branches
712 if (MBB->succ_size() == 1) {
713 // A conditional branch with only one successor is weird, but allowed.
715 report("MBB exits via conditional branch/branch through but only has "
716 "one CFG successor!", MBB);
717 else if (TBB != *MBB->succ_begin())
718 report("MBB exits via conditional branch/branch through but the CFG "
719 "successor don't match the actual successor!", MBB);
720 } else if (MBB->succ_size() != 2) {
721 report("MBB exits via conditional branch/branch but doesn't have "
722 "exactly two CFG successors!", MBB);
723 } else if (!matchPair(MBB->succ_begin(), TBB, FBB)) {
724 report("MBB exits via conditional branch/branch but the CFG "
725 "successors don't match the actual successors!", MBB);
728 report("MBB exits via conditional branch/branch but doesn't "
729 "contain any instructions!", MBB);
730 } else if (!MBB->back().isBarrier()) {
731 report("MBB exits via conditional branch/branch but doesn't end with a "
732 "barrier instruction!", MBB);
733 } else if (!MBB->back().isTerminator()) {
734 report("MBB exits via conditional branch/branch but the branch "
735 "isn't a terminator instruction!", MBB);
738 report("MBB exits via conditinal branch/branch but there's no "
742 report("AnalyzeBranch returned invalid data!", MBB);
747 if (MRI->tracksLiveness()) {
748 for (const auto &LI : MBB->liveins()) {
749 if (!TargetRegisterInfo::isPhysicalRegister(LI.PhysReg)) {
750 report("MBB live-in list contains non-physical register", MBB);
753 for (MCSubRegIterator SubRegs(LI.PhysReg, TRI, /*IncludeSelf=*/true);
754 SubRegs.isValid(); ++SubRegs)
755 regsLive.insert(*SubRegs);
759 const MachineFrameInfo &MFI = MF->getFrameInfo();
760 BitVector PR = MFI.getPristineRegs(*MF);
761 for (unsigned I : PR.set_bits()) {
762 for (MCSubRegIterator SubRegs(I, TRI, /*IncludeSelf=*/true);
763 SubRegs.isValid(); ++SubRegs)
764 regsLive.insert(*SubRegs);
771 lastIndex = Indexes->getMBBStartIdx(MBB);
774 // This function gets called for all bundle headers, including normal
775 // stand-alone unbundled instructions.
776 void MachineVerifier::visitMachineBundleBefore(const MachineInstr *MI) {
777 if (Indexes && Indexes->hasIndex(*MI)) {
778 SlotIndex idx = Indexes->getInstructionIndex(*MI);
779 if (!(idx > lastIndex)) {
780 report("Instruction index out of order", MI);
781 errs() << "Last instruction was at " << lastIndex << '\n';
786 // Ensure non-terminators don't follow terminators.
787 // Ignore predicated terminators formed by if conversion.
788 // FIXME: If conversion shouldn't need to violate this rule.
789 if (MI->isTerminator() && !TII->isPredicated(*MI)) {
790 if (!FirstTerminator)
791 FirstTerminator = MI;
792 } else if (FirstTerminator) {
793 report("Non-terminator instruction after the first terminator", MI);
794 errs() << "First terminator was:\t" << *FirstTerminator;
798 // The operands on an INLINEASM instruction must follow a template.
799 // Verify that the flag operands make sense.
800 void MachineVerifier::verifyInlineAsm(const MachineInstr *MI) {
801 // The first two operands on INLINEASM are the asm string and global flags.
802 if (MI->getNumOperands() < 2) {
803 report("Too few operands on inline asm", MI);
806 if (!MI->getOperand(0).isSymbol())
807 report("Asm string must be an external symbol", MI);
808 if (!MI->getOperand(1).isImm())
809 report("Asm flags must be an immediate", MI);
810 // Allowed flags are Extra_HasSideEffects = 1, Extra_IsAlignStack = 2,
811 // Extra_AsmDialect = 4, Extra_MayLoad = 8, and Extra_MayStore = 16,
812 // and Extra_IsConvergent = 32.
813 if (!isUInt<6>(MI->getOperand(1).getImm()))
814 report("Unknown asm flags", &MI->getOperand(1), 1);
816 static_assert(InlineAsm::MIOp_FirstOperand == 2, "Asm format changed");
818 unsigned OpNo = InlineAsm::MIOp_FirstOperand;
820 for (unsigned e = MI->getNumOperands(); OpNo < e; OpNo += NumOps) {
821 const MachineOperand &MO = MI->getOperand(OpNo);
822 // There may be implicit ops after the fixed operands.
825 NumOps = 1 + InlineAsm::getNumOperandRegisters(MO.getImm());
828 if (OpNo > MI->getNumOperands())
829 report("Missing operands in last group", MI);
831 // An optional MDNode follows the groups.
832 if (OpNo < MI->getNumOperands() && MI->getOperand(OpNo).isMetadata())
835 // All trailing operands must be implicit registers.
836 for (unsigned e = MI->getNumOperands(); OpNo < e; ++OpNo) {
837 const MachineOperand &MO = MI->getOperand(OpNo);
838 if (!MO.isReg() || !MO.isImplicit())
839 report("Expected implicit register after groups", &MO, OpNo);
843 void MachineVerifier::visitMachineInstrBefore(const MachineInstr *MI) {
844 const MCInstrDesc &MCID = MI->getDesc();
845 if (MI->getNumOperands() < MCID.getNumOperands()) {
846 report("Too few operands", MI);
847 errs() << MCID.getNumOperands() << " operands expected, but "
848 << MI->getNumOperands() << " given.\n";
851 if (MI->isPHI() && MF->getProperties().hasProperty(
852 MachineFunctionProperties::Property::NoPHIs))
853 report("Found PHI instruction with NoPHIs property set", MI);
855 // Check the tied operands.
856 if (MI->isInlineAsm())
859 // Check the MachineMemOperands for basic consistency.
860 for (MachineInstr::mmo_iterator I = MI->memoperands_begin(),
861 E = MI->memoperands_end(); I != E; ++I) {
862 if ((*I)->isLoad() && !MI->mayLoad())
863 report("Missing mayLoad flag", MI);
864 if ((*I)->isStore() && !MI->mayStore())
865 report("Missing mayStore flag", MI);
868 // Debug values must not have a slot index.
869 // Other instructions must have one, unless they are inside a bundle.
871 bool mapped = !LiveInts->isNotInMIMap(*MI);
872 if (MI->isDebugValue()) {
874 report("Debug instruction has a slot index", MI);
875 } else if (MI->isInsideBundle()) {
877 report("Instruction inside bundle has a slot index", MI);
880 report("Missing slot index", MI);
885 if (isPreISelGenericOpcode(MCID.getOpcode())) {
886 if (isFunctionSelected)
887 report("Unexpected generic instruction in a Selected function", MI);
889 // Generic instructions specify equality constraints between some
890 // of their operands. Make sure these are consistent.
891 SmallVector<LLT, 4> Types;
892 for (unsigned i = 0; i < MCID.getNumOperands(); ++i) {
893 if (!MCID.OpInfo[i].isGenericType())
895 size_t TypeIdx = MCID.OpInfo[i].getGenericTypeIndex();
896 Types.resize(std::max(TypeIdx + 1, Types.size()));
898 LLT OpTy = MRI->getType(MI->getOperand(i).getReg());
899 if (Types[TypeIdx].isValid() && Types[TypeIdx] != OpTy)
900 report("type mismatch in generic instruction", MI);
901 Types[TypeIdx] = OpTy;
905 // Generic opcodes must not have physical register operands.
906 if (isPreISelGenericOpcode(MCID.getOpcode())) {
907 for (auto &Op : MI->operands()) {
908 if (Op.isReg() && TargetRegisterInfo::isPhysicalRegister(Op.getReg()))
909 report("Generic instruction cannot have physical register", MI);
914 if (!TII->verifyInstruction(*MI, ErrorInfo))
915 report(ErrorInfo.data(), MI);
917 // Verify properties of various specific instruction types
918 switch(MI->getOpcode()) {
921 case TargetOpcode::G_LOAD:
922 case TargetOpcode::G_STORE:
923 // Generic loads and stores must have a single MachineMemOperand
924 // describing that access.
925 if (!MI->hasOneMemOperand())
926 report("Generic instruction accessing memory must have one mem operand",
929 case TargetOpcode::STATEPOINT:
930 if (!MI->getOperand(StatepointOpers::IDPos).isImm() ||
931 !MI->getOperand(StatepointOpers::NBytesPos).isImm() ||
932 !MI->getOperand(StatepointOpers::NCallArgsPos).isImm())
933 report("meta operands to STATEPOINT not constant!", MI);
936 auto VerifyStackMapConstant = [&](unsigned Offset) {
937 if (!MI->getOperand(Offset).isImm() ||
938 MI->getOperand(Offset).getImm() != StackMaps::ConstantOp ||
939 !MI->getOperand(Offset + 1).isImm())
940 report("stack map constant to STATEPOINT not well formed!", MI);
942 const unsigned VarStart = StatepointOpers(MI).getVarIdx();
943 VerifyStackMapConstant(VarStart + StatepointOpers::CCOffset);
944 VerifyStackMapConstant(VarStart + StatepointOpers::FlagsOffset);
945 VerifyStackMapConstant(VarStart + StatepointOpers::NumDeoptOperandsOffset);
947 // TODO: verify we have properly encoded deopt arguments
952 MachineVerifier::visitMachineOperand(const MachineOperand *MO, unsigned MONum) {
953 const MachineInstr *MI = MO->getParent();
954 const MCInstrDesc &MCID = MI->getDesc();
955 unsigned NumDefs = MCID.getNumDefs();
956 if (MCID.getOpcode() == TargetOpcode::PATCHPOINT)
957 NumDefs = (MONum == 0 && MO->isReg()) ? NumDefs : 0;
959 // The first MCID.NumDefs operands must be explicit register defines
960 if (MONum < NumDefs) {
961 const MCOperandInfo &MCOI = MCID.OpInfo[MONum];
963 report("Explicit definition must be a register", MO, MONum);
964 else if (!MO->isDef() && !MCOI.isOptionalDef())
965 report("Explicit definition marked as use", MO, MONum);
966 else if (MO->isImplicit())
967 report("Explicit definition marked as implicit", MO, MONum);
968 } else if (MONum < MCID.getNumOperands()) {
969 const MCOperandInfo &MCOI = MCID.OpInfo[MONum];
970 // Don't check if it's the last operand in a variadic instruction. See,
971 // e.g., LDM_RET in the arm back end.
973 !(MI->isVariadic() && MONum == MCID.getNumOperands()-1)) {
974 if (MO->isDef() && !MCOI.isOptionalDef())
975 report("Explicit operand marked as def", MO, MONum);
976 if (MO->isImplicit())
977 report("Explicit operand marked as implicit", MO, MONum);
980 int TiedTo = MCID.getOperandConstraint(MONum, MCOI::TIED_TO);
983 report("Tied use must be a register", MO, MONum);
984 else if (!MO->isTied())
985 report("Operand should be tied", MO, MONum);
986 else if (unsigned(TiedTo) != MI->findTiedOperandIdx(MONum))
987 report("Tied def doesn't match MCInstrDesc", MO, MONum);
988 else if (TargetRegisterInfo::isPhysicalRegister(MO->getReg())) {
989 const MachineOperand &MOTied = MI->getOperand(TiedTo);
991 report("Tied counterpart must be a register", &MOTied, TiedTo);
992 else if (TargetRegisterInfo::isPhysicalRegister(MOTied.getReg()) &&
993 MO->getReg() != MOTied.getReg())
994 report("Tied physical registers must match.", &MOTied, TiedTo);
996 } else if (MO->isReg() && MO->isTied())
997 report("Explicit operand should not be tied", MO, MONum);
999 // ARM adds %reg0 operands to indicate predicates. We'll allow that.
1000 if (MO->isReg() && !MO->isImplicit() && !MI->isVariadic() && MO->getReg())
1001 report("Extra explicit operand on non-variadic instruction", MO, MONum);
1004 switch (MO->getType()) {
1005 case MachineOperand::MO_Register: {
1006 const unsigned Reg = MO->getReg();
1009 if (MRI->tracksLiveness() && !MI->isDebugValue())
1010 checkLiveness(MO, MONum);
1012 // Verify the consistency of tied operands.
1014 unsigned OtherIdx = MI->findTiedOperandIdx(MONum);
1015 const MachineOperand &OtherMO = MI->getOperand(OtherIdx);
1016 if (!OtherMO.isReg())
1017 report("Must be tied to a register", MO, MONum);
1018 if (!OtherMO.isTied())
1019 report("Missing tie flags on tied operand", MO, MONum);
1020 if (MI->findTiedOperandIdx(OtherIdx) != MONum)
1021 report("Inconsistent tie links", MO, MONum);
1022 if (MONum < MCID.getNumDefs()) {
1023 if (OtherIdx < MCID.getNumOperands()) {
1024 if (-1 == MCID.getOperandConstraint(OtherIdx, MCOI::TIED_TO))
1025 report("Explicit def tied to explicit use without tie constraint",
1028 if (!OtherMO.isImplicit())
1029 report("Explicit def should be tied to implicit use", MO, MONum);
1034 // Verify two-address constraints after leaving SSA form.
1036 if (!MRI->isSSA() && MO->isUse() &&
1037 MI->isRegTiedToDefOperand(MONum, &DefIdx) &&
1038 Reg != MI->getOperand(DefIdx).getReg())
1039 report("Two-address instruction operands must be identical", MO, MONum);
1041 // Check register classes.
1042 if (MONum < MCID.getNumOperands() && !MO->isImplicit()) {
1043 unsigned SubIdx = MO->getSubReg();
1045 if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
1047 report("Illegal subregister index for physical register", MO, MONum);
1050 if (const TargetRegisterClass *DRC =
1051 TII->getRegClass(MCID, MONum, TRI, *MF)) {
1052 if (!DRC->contains(Reg)) {
1053 report("Illegal physical register for instruction", MO, MONum);
1054 errs() << TRI->getName(Reg) << " is not a "
1055 << TRI->getRegClassName(DRC) << " register.\n";
1059 // Virtual register.
1060 const TargetRegisterClass *RC = MRI->getRegClassOrNull(Reg);
1062 // This is a generic virtual register.
1064 // If we're post-Select, we can't have gvregs anymore.
1065 if (isFunctionSelected) {
1066 report("Generic virtual register invalid in a Selected function",
1071 // The gvreg must have a type and it must not have a SubIdx.
1072 LLT Ty = MRI->getType(Reg);
1073 if (!Ty.isValid()) {
1074 report("Generic virtual register must have a valid type", MO,
1079 const RegisterBank *RegBank = MRI->getRegBankOrNull(Reg);
1081 // If we're post-RegBankSelect, the gvreg must have a bank.
1082 if (!RegBank && isFunctionRegBankSelected) {
1083 report("Generic virtual register must have a bank in a "
1084 "RegBankSelected function",
1089 // Make sure the register fits into its register bank if any.
1090 if (RegBank && Ty.isValid() &&
1091 RegBank->getSize() < Ty.getSizeInBits()) {
1092 report("Register bank is too small for virtual register", MO,
1094 errs() << "Register bank " << RegBank->getName() << " too small("
1095 << RegBank->getSize() << ") to fit " << Ty.getSizeInBits()
1100 report("Generic virtual register does not subregister index", MO,
1105 // If this is a target specific instruction and this operand
1106 // has register class constraint, the virtual register must
1108 if (!isPreISelGenericOpcode(MCID.getOpcode()) &&
1109 TII->getRegClass(MCID, MONum, TRI, *MF)) {
1110 report("Virtual register does not match instruction constraint", MO,
1112 errs() << "Expect register class "
1113 << TRI->getRegClassName(
1114 TII->getRegClass(MCID, MONum, TRI, *MF))
1115 << " but got nothing\n";
1122 const TargetRegisterClass *SRC =
1123 TRI->getSubClassWithSubReg(RC, SubIdx);
1125 report("Invalid subregister index for virtual register", MO, MONum);
1126 errs() << "Register class " << TRI->getRegClassName(RC)
1127 << " does not support subreg index " << SubIdx << "\n";
1131 report("Invalid register class for subregister index", MO, MONum);
1132 errs() << "Register class " << TRI->getRegClassName(RC)
1133 << " does not fully support subreg index " << SubIdx << "\n";
1137 if (const TargetRegisterClass *DRC =
1138 TII->getRegClass(MCID, MONum, TRI, *MF)) {
1140 const TargetRegisterClass *SuperRC =
1141 TRI->getLargestLegalSuperClass(RC, *MF);
1143 report("No largest legal super class exists.", MO, MONum);
1146 DRC = TRI->getMatchingSuperRegClass(SuperRC, DRC, SubIdx);
1148 report("No matching super-reg register class.", MO, MONum);
1152 if (!RC->hasSuperClassEq(DRC)) {
1153 report("Illegal virtual register for instruction", MO, MONum);
1154 errs() << "Expected a " << TRI->getRegClassName(DRC)
1155 << " register, but got a " << TRI->getRegClassName(RC)
1164 case MachineOperand::MO_RegisterMask:
1165 regMasks.push_back(MO->getRegMask());
1168 case MachineOperand::MO_MachineBasicBlock:
1169 if (MI->isPHI() && !MO->getMBB()->isSuccessor(MI->getParent()))
1170 report("PHI operand is not in the CFG", MO, MONum);
1173 case MachineOperand::MO_FrameIndex:
1174 if (LiveStks && LiveStks->hasInterval(MO->getIndex()) &&
1175 LiveInts && !LiveInts->isNotInMIMap(*MI)) {
1176 int FI = MO->getIndex();
1177 LiveInterval &LI = LiveStks->getInterval(FI);
1178 SlotIndex Idx = LiveInts->getInstructionIndex(*MI);
1180 bool stores = MI->mayStore();
1181 bool loads = MI->mayLoad();
1182 // For a memory-to-memory move, we need to check if the frame
1183 // index is used for storing or loading, by inspecting the
1185 if (stores && loads) {
1186 for (auto *MMO : MI->memoperands()) {
1187 const PseudoSourceValue *PSV = MMO->getPseudoValue();
1188 if (PSV == nullptr) continue;
1189 const FixedStackPseudoSourceValue *Value =
1190 dyn_cast<FixedStackPseudoSourceValue>(PSV);
1191 if (Value == nullptr) continue;
1192 if (Value->getFrameIndex() != FI) continue;
1200 if (loads == stores)
1201 report("Missing fixed stack memoperand.", MI);
1203 if (loads && !LI.liveAt(Idx.getRegSlot(true))) {
1204 report("Instruction loads from dead spill slot", MO, MONum);
1205 errs() << "Live stack: " << LI << '\n';
1207 if (stores && !LI.liveAt(Idx.getRegSlot())) {
1208 report("Instruction stores to dead spill slot", MO, MONum);
1209 errs() << "Live stack: " << LI << '\n';
1219 void MachineVerifier::checkLivenessAtUse(const MachineOperand *MO,
1220 unsigned MONum, SlotIndex UseIdx, const LiveRange &LR, unsigned VRegOrUnit,
1221 LaneBitmask LaneMask) {
1222 LiveQueryResult LRQ = LR.Query(UseIdx);
1223 // Check if we have a segment at the use, note however that we only need one
1224 // live subregister range, the others may be dead.
1225 if (!LRQ.valueIn() && LaneMask.none()) {
1226 report("No live segment at use", MO, MONum);
1227 report_context_liverange(LR);
1228 report_context_vreg_regunit(VRegOrUnit);
1229 report_context(UseIdx);
1231 if (MO->isKill() && !LRQ.isKill()) {
1232 report("Live range continues after kill flag", MO, MONum);
1233 report_context_liverange(LR);
1234 report_context_vreg_regunit(VRegOrUnit);
1236 report_context_lanemask(LaneMask);
1237 report_context(UseIdx);
1241 void MachineVerifier::checkLivenessAtDef(const MachineOperand *MO,
1242 unsigned MONum, SlotIndex DefIdx, const LiveRange &LR, unsigned VRegOrUnit,
1243 LaneBitmask LaneMask) {
1244 if (const VNInfo *VNI = LR.getVNInfoAt(DefIdx)) {
1245 assert(VNI && "NULL valno is not allowed");
1246 if (VNI->def != DefIdx) {
1247 report("Inconsistent valno->def", MO, MONum);
1248 report_context_liverange(LR);
1249 report_context_vreg_regunit(VRegOrUnit);
1251 report_context_lanemask(LaneMask);
1252 report_context(*VNI);
1253 report_context(DefIdx);
1256 report("No live segment at def", MO, MONum);
1257 report_context_liverange(LR);
1258 report_context_vreg_regunit(VRegOrUnit);
1260 report_context_lanemask(LaneMask);
1261 report_context(DefIdx);
1263 // Check that, if the dead def flag is present, LiveInts agree.
1265 LiveQueryResult LRQ = LR.Query(DefIdx);
1266 if (!LRQ.isDeadDef()) {
1267 // In case of physregs we can have a non-dead definition on another
1269 bool otherDef = false;
1270 if (!TargetRegisterInfo::isVirtualRegister(VRegOrUnit)) {
1271 const MachineInstr &MI = *MO->getParent();
1272 for (const MachineOperand &MO : MI.operands()) {
1273 if (!MO.isReg() || !MO.isDef() || MO.isDead())
1275 unsigned Reg = MO.getReg();
1276 for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units) {
1277 if (*Units == VRegOrUnit) {
1286 report("Live range continues after dead def flag", MO, MONum);
1287 report_context_liverange(LR);
1288 report_context_vreg_regunit(VRegOrUnit);
1290 report_context_lanemask(LaneMask);
1296 void MachineVerifier::checkLiveness(const MachineOperand *MO, unsigned MONum) {
1297 const MachineInstr *MI = MO->getParent();
1298 const unsigned Reg = MO->getReg();
1300 // Both use and def operands can read a register.
1301 if (MO->readsReg()) {
1303 addRegWithSubRegs(regsKilled, Reg);
1305 // Check that LiveVars knows this kill.
1306 if (LiveVars && TargetRegisterInfo::isVirtualRegister(Reg) &&
1308 LiveVariables::VarInfo &VI = LiveVars->getVarInfo(Reg);
1309 if (!is_contained(VI.Kills, MI))
1310 report("Kill missing from LiveVariables", MO, MONum);
1313 // Check LiveInts liveness and kill.
1314 if (LiveInts && !LiveInts->isNotInMIMap(*MI)) {
1315 SlotIndex UseIdx = LiveInts->getInstructionIndex(*MI);
1316 // Check the cached regunit intervals.
1317 if (TargetRegisterInfo::isPhysicalRegister(Reg) && !isReserved(Reg)) {
1318 for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units) {
1319 if (const LiveRange *LR = LiveInts->getCachedRegUnit(*Units))
1320 checkLivenessAtUse(MO, MONum, UseIdx, *LR, *Units);
1324 if (TargetRegisterInfo::isVirtualRegister(Reg)) {
1325 if (LiveInts->hasInterval(Reg)) {
1326 // This is a virtual register interval.
1327 const LiveInterval &LI = LiveInts->getInterval(Reg);
1328 checkLivenessAtUse(MO, MONum, UseIdx, LI, Reg);
1330 if (LI.hasSubRanges() && !MO->isDef()) {
1331 unsigned SubRegIdx = MO->getSubReg();
1332 LaneBitmask MOMask = SubRegIdx != 0
1333 ? TRI->getSubRegIndexLaneMask(SubRegIdx)
1334 : MRI->getMaxLaneMaskForVReg(Reg);
1335 LaneBitmask LiveInMask;
1336 for (const LiveInterval::SubRange &SR : LI.subranges()) {
1337 if ((MOMask & SR.LaneMask).none())
1339 checkLivenessAtUse(MO, MONum, UseIdx, SR, Reg, SR.LaneMask);
1340 LiveQueryResult LRQ = SR.Query(UseIdx);
1342 LiveInMask |= SR.LaneMask;
1344 // At least parts of the register has to be live at the use.
1345 if ((LiveInMask & MOMask).none()) {
1346 report("No live subrange at use", MO, MONum);
1348 report_context(UseIdx);
1352 report("Virtual register has no live interval", MO, MONum);
1357 // Use of a dead register.
1358 if (!regsLive.count(Reg)) {
1359 if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
1360 // Reserved registers may be used even when 'dead'.
1361 bool Bad = !isReserved(Reg);
1362 // We are fine if just any subregister has a defined value.
1364 for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid();
1366 if (regsLive.count(*SubRegs)) {
1372 // If there is an additional implicit-use of a super register we stop
1373 // here. By definition we are fine if the super register is not
1374 // (completely) dead, if the complete super register is dead we will
1375 // get a report for its operand.
1377 for (const MachineOperand &MOP : MI->uses()) {
1380 if (!MOP.isImplicit())
1382 for (MCSubRegIterator SubRegs(MOP.getReg(), TRI); SubRegs.isValid();
1384 if (*SubRegs == Reg) {
1392 report("Using an undefined physical register", MO, MONum);
1393 } else if (MRI->def_empty(Reg)) {
1394 report("Reading virtual register without a def", MO, MONum);
1396 BBInfo &MInfo = MBBInfoMap[MI->getParent()];
1397 // We don't know which virtual registers are live in, so only complain
1398 // if vreg was killed in this MBB. Otherwise keep track of vregs that
1399 // must be live in. PHI instructions are handled separately.
1400 if (MInfo.regsKilled.count(Reg))
1401 report("Using a killed virtual register", MO, MONum);
1402 else if (!MI->isPHI())
1403 MInfo.vregsLiveIn.insert(std::make_pair(Reg, MI));
1409 // Register defined.
1410 // TODO: verify that earlyclobber ops are not used.
1412 addRegWithSubRegs(regsDead, Reg);
1414 addRegWithSubRegs(regsDefined, Reg);
1417 if (MRI->isSSA() && TargetRegisterInfo::isVirtualRegister(Reg) &&
1418 std::next(MRI->def_begin(Reg)) != MRI->def_end())
1419 report("Multiple virtual register defs in SSA form", MO, MONum);
1421 // Check LiveInts for a live segment, but only for virtual registers.
1422 if (LiveInts && !LiveInts->isNotInMIMap(*MI)) {
1423 SlotIndex DefIdx = LiveInts->getInstructionIndex(*MI);
1424 DefIdx = DefIdx.getRegSlot(MO->isEarlyClobber());
1426 if (TargetRegisterInfo::isVirtualRegister(Reg)) {
1427 if (LiveInts->hasInterval(Reg)) {
1428 const LiveInterval &LI = LiveInts->getInterval(Reg);
1429 checkLivenessAtDef(MO, MONum, DefIdx, LI, Reg);
1431 if (LI.hasSubRanges()) {
1432 unsigned SubRegIdx = MO->getSubReg();
1433 LaneBitmask MOMask = SubRegIdx != 0
1434 ? TRI->getSubRegIndexLaneMask(SubRegIdx)
1435 : MRI->getMaxLaneMaskForVReg(Reg);
1436 for (const LiveInterval::SubRange &SR : LI.subranges()) {
1437 if ((SR.LaneMask & MOMask).none())
1439 checkLivenessAtDef(MO, MONum, DefIdx, SR, Reg, SR.LaneMask);
1443 report("Virtual register has no Live interval", MO, MONum);
1450 void MachineVerifier::visitMachineInstrAfter(const MachineInstr *MI) {
1453 // This function gets called after visiting all instructions in a bundle. The
1454 // argument points to the bundle header.
1455 // Normal stand-alone instructions are also considered 'bundles', and this
1456 // function is called for all of them.
1457 void MachineVerifier::visitMachineBundleAfter(const MachineInstr *MI) {
1458 BBInfo &MInfo = MBBInfoMap[MI->getParent()];
1459 set_union(MInfo.regsKilled, regsKilled);
1460 set_subtract(regsLive, regsKilled); regsKilled.clear();
1461 // Kill any masked registers.
1462 while (!regMasks.empty()) {
1463 const uint32_t *Mask = regMasks.pop_back_val();
1464 for (RegSet::iterator I = regsLive.begin(), E = regsLive.end(); I != E; ++I)
1465 if (TargetRegisterInfo::isPhysicalRegister(*I) &&
1466 MachineOperand::clobbersPhysReg(Mask, *I))
1467 regsDead.push_back(*I);
1469 set_subtract(regsLive, regsDead); regsDead.clear();
1470 set_union(regsLive, regsDefined); regsDefined.clear();
1474 MachineVerifier::visitMachineBasicBlockAfter(const MachineBasicBlock *MBB) {
1475 MBBInfoMap[MBB].regsLiveOut = regsLive;
1479 SlotIndex stop = Indexes->getMBBEndIdx(MBB);
1480 if (!(stop > lastIndex)) {
1481 report("Block ends before last instruction index", MBB);
1482 errs() << "Block ends at " << stop
1483 << " last instruction was at " << lastIndex << '\n';
1489 // Calculate the largest possible vregsPassed sets. These are the registers that
1490 // can pass through an MBB live, but may not be live every time. It is assumed
1491 // that all vregsPassed sets are empty before the call.
1492 void MachineVerifier::calcRegsPassed() {
1493 // First push live-out regs to successors' vregsPassed. Remember the MBBs that
1494 // have any vregsPassed.
1495 SmallPtrSet<const MachineBasicBlock*, 8> todo;
1496 for (const auto &MBB : *MF) {
1497 BBInfo &MInfo = MBBInfoMap[&MBB];
1498 if (!MInfo.reachable)
1500 for (MachineBasicBlock::const_succ_iterator SuI = MBB.succ_begin(),
1501 SuE = MBB.succ_end(); SuI != SuE; ++SuI) {
1502 BBInfo &SInfo = MBBInfoMap[*SuI];
1503 if (SInfo.addPassed(MInfo.regsLiveOut))
1508 // Iteratively push vregsPassed to successors. This will converge to the same
1509 // final state regardless of DenseSet iteration order.
1510 while (!todo.empty()) {
1511 const MachineBasicBlock *MBB = *todo.begin();
1513 BBInfo &MInfo = MBBInfoMap[MBB];
1514 for (MachineBasicBlock::const_succ_iterator SuI = MBB->succ_begin(),
1515 SuE = MBB->succ_end(); SuI != SuE; ++SuI) {
1518 BBInfo &SInfo = MBBInfoMap[*SuI];
1519 if (SInfo.addPassed(MInfo.vregsPassed))
1525 // Calculate the set of virtual registers that must be passed through each basic
1526 // block in order to satisfy the requirements of successor blocks. This is very
1527 // similar to calcRegsPassed, only backwards.
1528 void MachineVerifier::calcRegsRequired() {
1529 // First push live-in regs to predecessors' vregsRequired.
1530 SmallPtrSet<const MachineBasicBlock*, 8> todo;
1531 for (const auto &MBB : *MF) {
1532 BBInfo &MInfo = MBBInfoMap[&MBB];
1533 for (MachineBasicBlock::const_pred_iterator PrI = MBB.pred_begin(),
1534 PrE = MBB.pred_end(); PrI != PrE; ++PrI) {
1535 BBInfo &PInfo = MBBInfoMap[*PrI];
1536 if (PInfo.addRequired(MInfo.vregsLiveIn))
1541 // Iteratively push vregsRequired to predecessors. This will converge to the
1542 // same final state regardless of DenseSet iteration order.
1543 while (!todo.empty()) {
1544 const MachineBasicBlock *MBB = *todo.begin();
1546 BBInfo &MInfo = MBBInfoMap[MBB];
1547 for (MachineBasicBlock::const_pred_iterator PrI = MBB->pred_begin(),
1548 PrE = MBB->pred_end(); PrI != PrE; ++PrI) {
1551 BBInfo &SInfo = MBBInfoMap[*PrI];
1552 if (SInfo.addRequired(MInfo.vregsRequired))
1558 // Check PHI instructions at the beginning of MBB. It is assumed that
1559 // calcRegsPassed has been run so BBInfo::isLiveOut is valid.
1560 void MachineVerifier::checkPHIOps(const MachineBasicBlock *MBB) {
1561 SmallPtrSet<const MachineBasicBlock*, 8> seen;
1562 for (const auto &BBI : *MBB) {
1567 for (unsigned i = 1, e = BBI.getNumOperands(); i != e; i += 2) {
1568 unsigned Reg = BBI.getOperand(i).getReg();
1569 const MachineBasicBlock *Pre = BBI.getOperand(i + 1).getMBB();
1570 if (!Pre->isSuccessor(MBB))
1573 BBInfo &PrInfo = MBBInfoMap[Pre];
1574 if (PrInfo.reachable && !PrInfo.isLiveOut(Reg))
1575 report("PHI operand is not live-out from predecessor",
1576 &BBI.getOperand(i), i);
1579 // Did we see all predecessors?
1580 for (MachineBasicBlock::const_pred_iterator PrI = MBB->pred_begin(),
1581 PrE = MBB->pred_end(); PrI != PrE; ++PrI) {
1582 if (!seen.count(*PrI)) {
1583 report("Missing PHI operand", &BBI);
1584 errs() << "BB#" << (*PrI)->getNumber()
1585 << " is a predecessor according to the CFG.\n";
1591 void MachineVerifier::visitMachineFunctionAfter() {
1594 for (const auto &MBB : *MF) {
1595 BBInfo &MInfo = MBBInfoMap[&MBB];
1597 // Skip unreachable MBBs.
1598 if (!MInfo.reachable)
1604 // Now check liveness info if available
1607 // Check for killed virtual registers that should be live out.
1608 for (const auto &MBB : *MF) {
1609 BBInfo &MInfo = MBBInfoMap[&MBB];
1610 for (RegSet::iterator
1611 I = MInfo.vregsRequired.begin(), E = MInfo.vregsRequired.end(); I != E;
1613 if (MInfo.regsKilled.count(*I)) {
1614 report("Virtual register killed in block, but needed live out.", &MBB);
1615 errs() << "Virtual register " << PrintReg(*I)
1616 << " is used after the block.\n";
1621 BBInfo &MInfo = MBBInfoMap[&MF->front()];
1622 for (RegSet::iterator
1623 I = MInfo.vregsRequired.begin(), E = MInfo.vregsRequired.end(); I != E;
1625 report("Virtual register defs don't dominate all uses.", MF);
1626 report_context_vreg(*I);
1631 verifyLiveVariables();
1633 verifyLiveIntervals();
1636 void MachineVerifier::verifyLiveVariables() {
1637 assert(LiveVars && "Don't call verifyLiveVariables without LiveVars");
1638 for (unsigned i = 0, e = MRI->getNumVirtRegs(); i != e; ++i) {
1639 unsigned Reg = TargetRegisterInfo::index2VirtReg(i);
1640 LiveVariables::VarInfo &VI = LiveVars->getVarInfo(Reg);
1641 for (const auto &MBB : *MF) {
1642 BBInfo &MInfo = MBBInfoMap[&MBB];
1644 // Our vregsRequired should be identical to LiveVariables' AliveBlocks
1645 if (MInfo.vregsRequired.count(Reg)) {
1646 if (!VI.AliveBlocks.test(MBB.getNumber())) {
1647 report("LiveVariables: Block missing from AliveBlocks", &MBB);
1648 errs() << "Virtual register " << PrintReg(Reg)
1649 << " must be live through the block.\n";
1652 if (VI.AliveBlocks.test(MBB.getNumber())) {
1653 report("LiveVariables: Block should not be in AliveBlocks", &MBB);
1654 errs() << "Virtual register " << PrintReg(Reg)
1655 << " is not needed live through the block.\n";
1662 void MachineVerifier::verifyLiveIntervals() {
1663 assert(LiveInts && "Don't call verifyLiveIntervals without LiveInts");
1664 for (unsigned i = 0, e = MRI->getNumVirtRegs(); i != e; ++i) {
1665 unsigned Reg = TargetRegisterInfo::index2VirtReg(i);
1667 // Spilling and splitting may leave unused registers around. Skip them.
1668 if (MRI->reg_nodbg_empty(Reg))
1671 if (!LiveInts->hasInterval(Reg)) {
1672 report("Missing live interval for virtual register", MF);
1673 errs() << PrintReg(Reg, TRI) << " still has defs or uses\n";
1677 const LiveInterval &LI = LiveInts->getInterval(Reg);
1678 assert(Reg == LI.reg && "Invalid reg to interval mapping");
1679 verifyLiveInterval(LI);
1682 // Verify all the cached regunit intervals.
1683 for (unsigned i = 0, e = TRI->getNumRegUnits(); i != e; ++i)
1684 if (const LiveRange *LR = LiveInts->getCachedRegUnit(i))
1685 verifyLiveRange(*LR, i);
1688 void MachineVerifier::verifyLiveRangeValue(const LiveRange &LR,
1689 const VNInfo *VNI, unsigned Reg,
1690 LaneBitmask LaneMask) {
1691 if (VNI->isUnused())
1694 const VNInfo *DefVNI = LR.getVNInfoAt(VNI->def);
1697 report("Value not live at VNInfo def and not marked unused", MF);
1698 report_context(LR, Reg, LaneMask);
1699 report_context(*VNI);
1703 if (DefVNI != VNI) {
1704 report("Live segment at def has different VNInfo", MF);
1705 report_context(LR, Reg, LaneMask);
1706 report_context(*VNI);
1710 const MachineBasicBlock *MBB = LiveInts->getMBBFromIndex(VNI->def);
1712 report("Invalid VNInfo definition index", MF);
1713 report_context(LR, Reg, LaneMask);
1714 report_context(*VNI);
1718 if (VNI->isPHIDef()) {
1719 if (VNI->def != LiveInts->getMBBStartIdx(MBB)) {
1720 report("PHIDef VNInfo is not defined at MBB start", MBB);
1721 report_context(LR, Reg, LaneMask);
1722 report_context(*VNI);
1728 const MachineInstr *MI = LiveInts->getInstructionFromIndex(VNI->def);
1730 report("No instruction at VNInfo def index", MBB);
1731 report_context(LR, Reg, LaneMask);
1732 report_context(*VNI);
1737 bool hasDef = false;
1738 bool isEarlyClobber = false;
1739 for (ConstMIBundleOperands MOI(*MI); MOI.isValid(); ++MOI) {
1740 if (!MOI->isReg() || !MOI->isDef())
1742 if (TargetRegisterInfo::isVirtualRegister(Reg)) {
1743 if (MOI->getReg() != Reg)
1746 if (!TargetRegisterInfo::isPhysicalRegister(MOI->getReg()) ||
1747 !TRI->hasRegUnit(MOI->getReg(), Reg))
1750 if (LaneMask.any() &&
1751 (TRI->getSubRegIndexLaneMask(MOI->getSubReg()) & LaneMask).none())
1754 if (MOI->isEarlyClobber())
1755 isEarlyClobber = true;
1759 report("Defining instruction does not modify register", MI);
1760 report_context(LR, Reg, LaneMask);
1761 report_context(*VNI);
1764 // Early clobber defs begin at USE slots, but other defs must begin at
1766 if (isEarlyClobber) {
1767 if (!VNI->def.isEarlyClobber()) {
1768 report("Early clobber def must be at an early-clobber slot", MBB);
1769 report_context(LR, Reg, LaneMask);
1770 report_context(*VNI);
1772 } else if (!VNI->def.isRegister()) {
1773 report("Non-PHI, non-early clobber def must be at a register slot", MBB);
1774 report_context(LR, Reg, LaneMask);
1775 report_context(*VNI);
1780 void MachineVerifier::verifyLiveRangeSegment(const LiveRange &LR,
1781 const LiveRange::const_iterator I,
1782 unsigned Reg, LaneBitmask LaneMask)
1784 const LiveRange::Segment &S = *I;
1785 const VNInfo *VNI = S.valno;
1786 assert(VNI && "Live segment has no valno");
1788 if (VNI->id >= LR.getNumValNums() || VNI != LR.getValNumInfo(VNI->id)) {
1789 report("Foreign valno in live segment", MF);
1790 report_context(LR, Reg, LaneMask);
1792 report_context(*VNI);
1795 if (VNI->isUnused()) {
1796 report("Live segment valno is marked unused", MF);
1797 report_context(LR, Reg, LaneMask);
1801 const MachineBasicBlock *MBB = LiveInts->getMBBFromIndex(S.start);
1803 report("Bad start of live segment, no basic block", MF);
1804 report_context(LR, Reg, LaneMask);
1808 SlotIndex MBBStartIdx = LiveInts->getMBBStartIdx(MBB);
1809 if (S.start != MBBStartIdx && S.start != VNI->def) {
1810 report("Live segment must begin at MBB entry or valno def", MBB);
1811 report_context(LR, Reg, LaneMask);
1815 const MachineBasicBlock *EndMBB =
1816 LiveInts->getMBBFromIndex(S.end.getPrevSlot());
1818 report("Bad end of live segment, no basic block", MF);
1819 report_context(LR, Reg, LaneMask);
1824 // No more checks for live-out segments.
1825 if (S.end == LiveInts->getMBBEndIdx(EndMBB))
1828 // RegUnit intervals are allowed dead phis.
1829 if (!TargetRegisterInfo::isVirtualRegister(Reg) && VNI->isPHIDef() &&
1830 S.start == VNI->def && S.end == VNI->def.getDeadSlot())
1833 // The live segment is ending inside EndMBB
1834 const MachineInstr *MI =
1835 LiveInts->getInstructionFromIndex(S.end.getPrevSlot());
1837 report("Live segment doesn't end at a valid instruction", EndMBB);
1838 report_context(LR, Reg, LaneMask);
1843 // The block slot must refer to a basic block boundary.
1844 if (S.end.isBlock()) {
1845 report("Live segment ends at B slot of an instruction", EndMBB);
1846 report_context(LR, Reg, LaneMask);
1850 if (S.end.isDead()) {
1851 // Segment ends on the dead slot.
1852 // That means there must be a dead def.
1853 if (!SlotIndex::isSameInstr(S.start, S.end)) {
1854 report("Live segment ending at dead slot spans instructions", EndMBB);
1855 report_context(LR, Reg, LaneMask);
1860 // A live segment can only end at an early-clobber slot if it is being
1861 // redefined by an early-clobber def.
1862 if (S.end.isEarlyClobber()) {
1863 if (I+1 == LR.end() || (I+1)->start != S.end) {
1864 report("Live segment ending at early clobber slot must be "
1865 "redefined by an EC def in the same instruction", EndMBB);
1866 report_context(LR, Reg, LaneMask);
1871 // The following checks only apply to virtual registers. Physreg liveness
1872 // is too weird to check.
1873 if (TargetRegisterInfo::isVirtualRegister(Reg)) {
1874 // A live segment can end with either a redefinition, a kill flag on a
1875 // use, or a dead flag on a def.
1876 bool hasRead = false;
1877 bool hasSubRegDef = false;
1878 bool hasDeadDef = false;
1879 for (ConstMIBundleOperands MOI(*MI); MOI.isValid(); ++MOI) {
1880 if (!MOI->isReg() || MOI->getReg() != Reg)
1882 unsigned Sub = MOI->getSubReg();
1883 LaneBitmask SLM = Sub != 0 ? TRI->getSubRegIndexLaneMask(Sub)
1884 : LaneBitmask::getAll();
1887 hasSubRegDef = true;
1888 // An operand vreg0:sub0<def> reads vreg0:sub1..n. Invert the lane
1889 // mask for subregister defs. Read-undef defs will be handled by
1896 if (LaneMask.any() && (LaneMask & SLM).none())
1898 if (MOI->readsReg())
1901 if (S.end.isDead()) {
1902 // Make sure that the corresponding machine operand for a "dead" live
1903 // range has the dead flag. We cannot perform this check for subregister
1904 // liveranges as partially dead values are allowed.
1905 if (LaneMask.none() && !hasDeadDef) {
1906 report("Instruction ending live segment on dead slot has no dead flag",
1908 report_context(LR, Reg, LaneMask);
1913 // When tracking subregister liveness, the main range must start new
1914 // values on partial register writes, even if there is no read.
1915 if (!MRI->shouldTrackSubRegLiveness(Reg) || LaneMask.any() ||
1917 report("Instruction ending live segment doesn't read the register",
1919 report_context(LR, Reg, LaneMask);
1926 // Now check all the basic blocks in this live segment.
1927 MachineFunction::const_iterator MFI = MBB->getIterator();
1928 // Is this live segment the beginning of a non-PHIDef VN?
1929 if (S.start == VNI->def && !VNI->isPHIDef()) {
1930 // Not live-in to any blocks.
1937 assert(LiveInts->isLiveInToMBB(LR, &*MFI));
1938 // We don't know how to track physregs into a landing pad.
1939 if (!TargetRegisterInfo::isVirtualRegister(Reg) &&
1941 if (&*MFI == EndMBB)
1947 // Is VNI a PHI-def in the current block?
1948 bool IsPHI = VNI->isPHIDef() &&
1949 VNI->def == LiveInts->getMBBStartIdx(&*MFI);
1951 // Check that VNI is live-out of all predecessors.
1952 for (MachineBasicBlock::const_pred_iterator PI = MFI->pred_begin(),
1953 PE = MFI->pred_end(); PI != PE; ++PI) {
1954 SlotIndex PEnd = LiveInts->getMBBEndIdx(*PI);
1955 const VNInfo *PVNI = LR.getVNInfoBefore(PEnd);
1957 // All predecessors must have a live-out value. However for a phi
1958 // instruction with subregister intervals
1959 // only one of the subregisters (not necessarily the current one) needs to
1961 if (!PVNI && (LaneMask.none() || !IsPHI) ) {
1962 report("Register not marked live out of predecessor", *PI);
1963 report_context(LR, Reg, LaneMask);
1964 report_context(*VNI);
1965 errs() << " live into BB#" << MFI->getNumber()
1966 << '@' << LiveInts->getMBBStartIdx(&*MFI) << ", not live before "
1971 // Only PHI-defs can take different predecessor values.
1972 if (!IsPHI && PVNI != VNI) {
1973 report("Different value live out of predecessor", *PI);
1974 report_context(LR, Reg, LaneMask);
1975 errs() << "Valno #" << PVNI->id << " live out of BB#"
1976 << (*PI)->getNumber() << '@' << PEnd << "\nValno #" << VNI->id
1977 << " live into BB#" << MFI->getNumber() << '@'
1978 << LiveInts->getMBBStartIdx(&*MFI) << '\n';
1981 if (&*MFI == EndMBB)
1987 void MachineVerifier::verifyLiveRange(const LiveRange &LR, unsigned Reg,
1988 LaneBitmask LaneMask) {
1989 for (const VNInfo *VNI : LR.valnos)
1990 verifyLiveRangeValue(LR, VNI, Reg, LaneMask);
1992 for (LiveRange::const_iterator I = LR.begin(), E = LR.end(); I != E; ++I)
1993 verifyLiveRangeSegment(LR, I, Reg, LaneMask);
1996 void MachineVerifier::verifyLiveInterval(const LiveInterval &LI) {
1997 unsigned Reg = LI.reg;
1998 assert(TargetRegisterInfo::isVirtualRegister(Reg));
1999 verifyLiveRange(LI, Reg);
2002 LaneBitmask MaxMask = MRI->getMaxLaneMaskForVReg(Reg);
2003 for (const LiveInterval::SubRange &SR : LI.subranges()) {
2004 if ((Mask & SR.LaneMask).any()) {
2005 report("Lane masks of sub ranges overlap in live interval", MF);
2008 if ((SR.LaneMask & ~MaxMask).any()) {
2009 report("Subrange lanemask is invalid", MF);
2013 report("Subrange must not be empty", MF);
2014 report_context(SR, LI.reg, SR.LaneMask);
2016 Mask |= SR.LaneMask;
2017 verifyLiveRange(SR, LI.reg, SR.LaneMask);
2018 if (!LI.covers(SR)) {
2019 report("A Subrange is not covered by the main range", MF);
2024 // Check the LI only has one connected component.
2025 ConnectedVNInfoEqClasses ConEQ(*LiveInts);
2026 unsigned NumComp = ConEQ.Classify(LI);
2028 report("Multiple connected components in live interval", MF);
2030 for (unsigned comp = 0; comp != NumComp; ++comp) {
2031 errs() << comp << ": valnos";
2032 for (LiveInterval::const_vni_iterator I = LI.vni_begin(),
2033 E = LI.vni_end(); I!=E; ++I)
2034 if (comp == ConEQ.getEqClass(*I))
2035 errs() << ' ' << (*I)->id;
2042 // FrameSetup and FrameDestroy can have zero adjustment, so using a single
2043 // integer, we can't tell whether it is a FrameSetup or FrameDestroy if the
2045 // We use a bool plus an integer to capture the stack state.
2046 struct StackStateOfBB {
2047 StackStateOfBB() : EntryValue(0), ExitValue(0), EntryIsSetup(false),
2048 ExitIsSetup(false) { }
2049 StackStateOfBB(int EntryVal, int ExitVal, bool EntrySetup, bool ExitSetup) :
2050 EntryValue(EntryVal), ExitValue(ExitVal), EntryIsSetup(EntrySetup),
2051 ExitIsSetup(ExitSetup) { }
2052 // Can be negative, which means we are setting up a frame.
2060 /// Make sure on every path through the CFG, a FrameSetup <n> is always followed
2061 /// by a FrameDestroy <n>, stack adjustments are identical on all
2062 /// CFG edges to a merge point, and frame is destroyed at end of a return block.
2063 void MachineVerifier::verifyStackFrame() {
2064 unsigned FrameSetupOpcode = TII->getCallFrameSetupOpcode();
2065 unsigned FrameDestroyOpcode = TII->getCallFrameDestroyOpcode();
2066 if (FrameSetupOpcode == ~0u && FrameDestroyOpcode == ~0u)
2069 SmallVector<StackStateOfBB, 8> SPState;
2070 SPState.resize(MF->getNumBlockIDs());
2071 df_iterator_default_set<const MachineBasicBlock*> Reachable;
2073 // Visit the MBBs in DFS order.
2074 for (df_ext_iterator<const MachineFunction*,
2075 df_iterator_default_set<const MachineBasicBlock*> >
2076 DFI = df_ext_begin(MF, Reachable), DFE = df_ext_end(MF, Reachable);
2077 DFI != DFE; ++DFI) {
2078 const MachineBasicBlock *MBB = *DFI;
2080 StackStateOfBB BBState;
2081 // Check the exit state of the DFS stack predecessor.
2082 if (DFI.getPathLength() >= 2) {
2083 const MachineBasicBlock *StackPred = DFI.getPath(DFI.getPathLength() - 2);
2084 assert(Reachable.count(StackPred) &&
2085 "DFS stack predecessor is already visited.\n");
2086 BBState.EntryValue = SPState[StackPred->getNumber()].ExitValue;
2087 BBState.EntryIsSetup = SPState[StackPred->getNumber()].ExitIsSetup;
2088 BBState.ExitValue = BBState.EntryValue;
2089 BBState.ExitIsSetup = BBState.EntryIsSetup;
2092 // Update stack state by checking contents of MBB.
2093 for (const auto &I : *MBB) {
2094 if (I.getOpcode() == FrameSetupOpcode) {
2095 if (BBState.ExitIsSetup)
2096 report("FrameSetup is after another FrameSetup", &I);
2097 BBState.ExitValue -= TII->getFrameTotalSize(I);
2098 BBState.ExitIsSetup = true;
2101 if (I.getOpcode() == FrameDestroyOpcode) {
2102 int Size = TII->getFrameTotalSize(I);
2103 if (!BBState.ExitIsSetup)
2104 report("FrameDestroy is not after a FrameSetup", &I);
2105 int AbsSPAdj = BBState.ExitValue < 0 ? -BBState.ExitValue :
2107 if (BBState.ExitIsSetup && AbsSPAdj != Size) {
2108 report("FrameDestroy <n> is after FrameSetup <m>", &I);
2109 errs() << "FrameDestroy <" << Size << "> is after FrameSetup <"
2110 << AbsSPAdj << ">.\n";
2112 BBState.ExitValue += Size;
2113 BBState.ExitIsSetup = false;
2116 SPState[MBB->getNumber()] = BBState;
2118 // Make sure the exit state of any predecessor is consistent with the entry
2120 for (MachineBasicBlock::const_pred_iterator I = MBB->pred_begin(),
2121 E = MBB->pred_end(); I != E; ++I) {
2122 if (Reachable.count(*I) &&
2123 (SPState[(*I)->getNumber()].ExitValue != BBState.EntryValue ||
2124 SPState[(*I)->getNumber()].ExitIsSetup != BBState.EntryIsSetup)) {
2125 report("The exit stack state of a predecessor is inconsistent.", MBB);
2126 errs() << "Predecessor BB#" << (*I)->getNumber() << " has exit state ("
2127 << SPState[(*I)->getNumber()].ExitValue << ", "
2128 << SPState[(*I)->getNumber()].ExitIsSetup
2129 << "), while BB#" << MBB->getNumber() << " has entry state ("
2130 << BBState.EntryValue << ", " << BBState.EntryIsSetup << ").\n";
2134 // Make sure the entry state of any successor is consistent with the exit
2136 for (MachineBasicBlock::const_succ_iterator I = MBB->succ_begin(),
2137 E = MBB->succ_end(); I != E; ++I) {
2138 if (Reachable.count(*I) &&
2139 (SPState[(*I)->getNumber()].EntryValue != BBState.ExitValue ||
2140 SPState[(*I)->getNumber()].EntryIsSetup != BBState.ExitIsSetup)) {
2141 report("The entry stack state of a successor is inconsistent.", MBB);
2142 errs() << "Successor BB#" << (*I)->getNumber() << " has entry state ("
2143 << SPState[(*I)->getNumber()].EntryValue << ", "
2144 << SPState[(*I)->getNumber()].EntryIsSetup
2145 << "), while BB#" << MBB->getNumber() << " has exit state ("
2146 << BBState.ExitValue << ", " << BBState.ExitIsSetup << ").\n";
2150 // Make sure a basic block with return ends with zero stack adjustment.
2151 if (!MBB->empty() && MBB->back().isReturn()) {
2152 if (BBState.ExitIsSetup)
2153 report("A return block ends with a FrameSetup.", MBB);
2154 if (BBState.ExitValue)
2155 report("A return block ends with a nonzero stack adjustment.", MBB);