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/CodeGen/Passes.h"
27 #include "llvm/ADT/DenseSet.h"
28 #include "llvm/ADT/DepthFirstIterator.h"
29 #include "llvm/ADT/SetOperations.h"
30 #include "llvm/ADT/SmallVector.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/MachineInstrBundle.h"
37 #include "llvm/CodeGen/MachineMemOperand.h"
38 #include "llvm/CodeGen/MachineRegisterInfo.h"
39 #include "llvm/IR/BasicBlock.h"
40 #include "llvm/IR/InlineAsm.h"
41 #include "llvm/IR/Instructions.h"
42 #include "llvm/MC/MCAsmInfo.h"
43 #include "llvm/Support/Debug.h"
44 #include "llvm/Support/ErrorHandling.h"
45 #include "llvm/Support/FileSystem.h"
46 #include "llvm/Support/raw_ostream.h"
47 #include "llvm/Target/TargetInstrInfo.h"
48 #include "llvm/Target/TargetMachine.h"
49 #include "llvm/Target/TargetRegisterInfo.h"
53 struct MachineVerifier {
55 MachineVerifier(Pass *pass, const char *b) :
58 OutFileName(getenv("LLVM_VERIFY_MACHINEINSTRS"))
61 bool runOnMachineFunction(MachineFunction &MF);
65 const char *const OutFileName;
67 const MachineFunction *MF;
68 const TargetMachine *TM;
69 const TargetInstrInfo *TII;
70 const TargetRegisterInfo *TRI;
71 const MachineRegisterInfo *MRI;
75 typedef SmallVector<unsigned, 16> RegVector;
76 typedef SmallVector<const uint32_t*, 4> RegMaskVector;
77 typedef DenseSet<unsigned> RegSet;
78 typedef DenseMap<unsigned, const MachineInstr*> RegMap;
79 typedef SmallPtrSet<const MachineBasicBlock*, 8> BlockSet;
81 const MachineInstr *FirstTerminator;
82 BlockSet FunctionBlocks;
84 BitVector regsReserved;
86 RegVector regsDefined, regsDead, regsKilled;
87 RegMaskVector regMasks;
88 RegSet regsLiveInButUnused;
92 // Add Reg and any sub-registers to RV
93 void addRegWithSubRegs(RegVector &RV, unsigned Reg) {
95 if (TargetRegisterInfo::isPhysicalRegister(Reg))
96 for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs)
97 RV.push_back(*SubRegs);
101 // Is this MBB reachable from the MF entry point?
104 // Vregs that must be live in because they are used without being
105 // defined. Map value is the user.
108 // Regs killed in MBB. They may be defined again, and will then be in both
109 // regsKilled and regsLiveOut.
112 // Regs defined in MBB and live out. Note that vregs passing through may
113 // be live out without being mentioned here.
116 // Vregs that pass through MBB untouched. This set is disjoint from
117 // regsKilled and regsLiveOut.
120 // Vregs that must pass through MBB because they are needed by a successor
121 // block. This set is disjoint from regsLiveOut.
122 RegSet vregsRequired;
124 // Set versions of block's predecessor and successor lists.
125 BlockSet Preds, Succs;
127 BBInfo() : reachable(false) {}
129 // Add register to vregsPassed if it belongs there. Return true if
131 bool addPassed(unsigned Reg) {
132 if (!TargetRegisterInfo::isVirtualRegister(Reg))
134 if (regsKilled.count(Reg) || regsLiveOut.count(Reg))
136 return vregsPassed.insert(Reg).second;
139 // Same for a full set.
140 bool addPassed(const RegSet &RS) {
141 bool changed = false;
142 for (RegSet::const_iterator I = RS.begin(), E = RS.end(); I != E; ++I)
148 // Add register to vregsRequired if it belongs there. Return true if
150 bool addRequired(unsigned Reg) {
151 if (!TargetRegisterInfo::isVirtualRegister(Reg))
153 if (regsLiveOut.count(Reg))
155 return vregsRequired.insert(Reg).second;
158 // Same for a full set.
159 bool addRequired(const RegSet &RS) {
160 bool changed = false;
161 for (RegSet::const_iterator I = RS.begin(), E = RS.end(); I != E; ++I)
167 // Same for a full map.
168 bool addRequired(const RegMap &RM) {
169 bool changed = false;
170 for (RegMap::const_iterator I = RM.begin(), E = RM.end(); I != E; ++I)
171 if (addRequired(I->first))
176 // Live-out registers are either in regsLiveOut or vregsPassed.
177 bool isLiveOut(unsigned Reg) const {
178 return regsLiveOut.count(Reg) || vregsPassed.count(Reg);
182 // Extra register info per MBB.
183 DenseMap<const MachineBasicBlock*, BBInfo> MBBInfoMap;
185 bool isReserved(unsigned Reg) {
186 return Reg < regsReserved.size() && regsReserved.test(Reg);
189 bool isAllocatable(unsigned Reg) {
190 return Reg < TRI->getNumRegs() && MRI->isAllocatable(Reg);
193 // Analysis information if available
194 LiveVariables *LiveVars;
195 LiveIntervals *LiveInts;
196 LiveStacks *LiveStks;
197 SlotIndexes *Indexes;
199 void visitMachineFunctionBefore();
200 void visitMachineBasicBlockBefore(const MachineBasicBlock *MBB);
201 void visitMachineBundleBefore(const MachineInstr *MI);
202 void visitMachineInstrBefore(const MachineInstr *MI);
203 void visitMachineOperand(const MachineOperand *MO, unsigned MONum);
204 void visitMachineInstrAfter(const MachineInstr *MI);
205 void visitMachineBundleAfter(const MachineInstr *MI);
206 void visitMachineBasicBlockAfter(const MachineBasicBlock *MBB);
207 void visitMachineFunctionAfter();
209 void report(const char *msg, const MachineFunction *MF);
210 void report(const char *msg, const MachineBasicBlock *MBB);
211 void report(const char *msg, const MachineInstr *MI);
212 void report(const char *msg, const MachineOperand *MO, unsigned MONum);
213 void report(const char *msg, const MachineFunction *MF,
214 const LiveInterval &LI);
215 void report(const char *msg, const MachineBasicBlock *MBB,
216 const LiveInterval &LI);
217 void report(const char *msg, const MachineFunction *MF,
218 const LiveRange &LR);
219 void report(const char *msg, const MachineBasicBlock *MBB,
220 const LiveRange &LR);
222 void verifyInlineAsm(const MachineInstr *MI);
224 void checkLiveness(const MachineOperand *MO, unsigned MONum);
225 void markReachable(const MachineBasicBlock *MBB);
226 void calcRegsPassed();
227 void checkPHIOps(const MachineBasicBlock *MBB);
229 void calcRegsRequired();
230 void verifyLiveVariables();
231 void verifyLiveIntervals();
232 void verifyLiveInterval(const LiveInterval&);
233 void verifyLiveRangeValue(const LiveRange&, const VNInfo*, unsigned);
234 void verifyLiveRangeSegment(const LiveRange&,
235 const LiveRange::const_iterator I, unsigned);
236 void verifyLiveRange(const LiveRange&, unsigned);
238 void verifyStackFrame();
241 struct MachineVerifierPass : public MachineFunctionPass {
242 static char ID; // Pass ID, replacement for typeid
243 const char *const Banner;
245 MachineVerifierPass(const char *b = nullptr)
246 : MachineFunctionPass(ID), Banner(b) {
247 initializeMachineVerifierPassPass(*PassRegistry::getPassRegistry());
250 void getAnalysisUsage(AnalysisUsage &AU) const override {
251 AU.setPreservesAll();
252 MachineFunctionPass::getAnalysisUsage(AU);
255 bool runOnMachineFunction(MachineFunction &MF) override {
256 MF.verify(this, Banner);
263 char MachineVerifierPass::ID = 0;
264 INITIALIZE_PASS(MachineVerifierPass, "machineverifier",
265 "Verify generated machine code", false, false)
267 FunctionPass *llvm::createMachineVerifierPass(const char *Banner) {
268 return new MachineVerifierPass(Banner);
271 void MachineFunction::verify(Pass *p, const char *Banner) const {
272 MachineVerifier(p, Banner)
273 .runOnMachineFunction(const_cast<MachineFunction&>(*this));
276 bool MachineVerifier::runOnMachineFunction(MachineFunction &MF) {
277 raw_ostream *OutFile = nullptr;
279 std::string ErrorInfo;
280 OutFile = new raw_fd_ostream(OutFileName, ErrorInfo,
281 sys::fs::F_Append | sys::fs::F_Text);
282 if (!ErrorInfo.empty()) {
283 errs() << "Error opening '" << OutFileName << "': " << ErrorInfo << '\n';
295 TM = &MF.getTarget();
296 TII = TM->getInstrInfo();
297 TRI = TM->getRegisterInfo();
298 MRI = &MF.getRegInfo();
305 LiveInts = PASS->getAnalysisIfAvailable<LiveIntervals>();
306 // We don't want to verify LiveVariables if LiveIntervals is available.
308 LiveVars = PASS->getAnalysisIfAvailable<LiveVariables>();
309 LiveStks = PASS->getAnalysisIfAvailable<LiveStacks>();
310 Indexes = PASS->getAnalysisIfAvailable<SlotIndexes>();
313 visitMachineFunctionBefore();
314 for (MachineFunction::const_iterator MFI = MF.begin(), MFE = MF.end();
316 visitMachineBasicBlockBefore(MFI);
317 // Keep track of the current bundle header.
318 const MachineInstr *CurBundle = nullptr;
319 // Do we expect the next instruction to be part of the same bundle?
320 bool InBundle = false;
322 for (MachineBasicBlock::const_instr_iterator MBBI = MFI->instr_begin(),
323 MBBE = MFI->instr_end(); MBBI != MBBE; ++MBBI) {
324 if (MBBI->getParent() != MFI) {
325 report("Bad instruction parent pointer", MFI);
326 *OS << "Instruction: " << *MBBI;
330 // Check for consistent bundle flags.
331 if (InBundle && !MBBI->isBundledWithPred())
332 report("Missing BundledPred flag, "
333 "BundledSucc was set on predecessor", MBBI);
334 if (!InBundle && MBBI->isBundledWithPred())
335 report("BundledPred flag is set, "
336 "but BundledSucc not set on predecessor", MBBI);
338 // Is this a bundle header?
339 if (!MBBI->isInsideBundle()) {
341 visitMachineBundleAfter(CurBundle);
343 visitMachineBundleBefore(CurBundle);
344 } else if (!CurBundle)
345 report("No bundle header", MBBI);
346 visitMachineInstrBefore(MBBI);
347 for (unsigned I = 0, E = MBBI->getNumOperands(); I != E; ++I)
348 visitMachineOperand(&MBBI->getOperand(I), I);
349 visitMachineInstrAfter(MBBI);
351 // Was this the last bundled instruction?
352 InBundle = MBBI->isBundledWithSucc();
355 visitMachineBundleAfter(CurBundle);
357 report("BundledSucc flag set on last instruction in block", &MFI->back());
358 visitMachineBasicBlockAfter(MFI);
360 visitMachineFunctionAfter();
364 else if (foundErrors)
365 report_fatal_error("Found "+Twine(foundErrors)+" machine code errors.");
373 regsLiveInButUnused.clear();
376 return false; // no changes
379 void MachineVerifier::report(const char *msg, const MachineFunction *MF) {
382 if (!foundErrors++) {
384 *OS << "# " << Banner << '\n';
385 MF->print(*OS, Indexes);
387 *OS << "*** Bad machine code: " << msg << " ***\n"
388 << "- function: " << MF->getName() << "\n";
391 void MachineVerifier::report(const char *msg, const MachineBasicBlock *MBB) {
393 report(msg, MBB->getParent());
394 *OS << "- basic block: BB#" << MBB->getNumber()
395 << ' ' << MBB->getName()
396 << " (" << (const void*)MBB << ')';
398 *OS << " [" << Indexes->getMBBStartIdx(MBB)
399 << ';' << Indexes->getMBBEndIdx(MBB) << ')';
403 void MachineVerifier::report(const char *msg, const MachineInstr *MI) {
405 report(msg, MI->getParent());
406 *OS << "- instruction: ";
407 if (Indexes && Indexes->hasIndex(MI))
408 *OS << Indexes->getInstructionIndex(MI) << '\t';
412 void MachineVerifier::report(const char *msg,
413 const MachineOperand *MO, unsigned MONum) {
415 report(msg, MO->getParent());
416 *OS << "- operand " << MONum << ": ";
421 void MachineVerifier::report(const char *msg, const MachineFunction *MF,
422 const LiveInterval &LI) {
424 *OS << "- interval: " << LI << '\n';
427 void MachineVerifier::report(const char *msg, const MachineBasicBlock *MBB,
428 const LiveInterval &LI) {
430 *OS << "- interval: " << LI << '\n';
433 void MachineVerifier::report(const char *msg, const MachineBasicBlock *MBB,
434 const LiveRange &LR) {
436 *OS << "- liverange: " << LR << "\n";
439 void MachineVerifier::report(const char *msg, const MachineFunction *MF,
440 const LiveRange &LR) {
442 *OS << "- liverange: " << LR << "\n";
445 void MachineVerifier::markReachable(const MachineBasicBlock *MBB) {
446 BBInfo &MInfo = MBBInfoMap[MBB];
447 if (!MInfo.reachable) {
448 MInfo.reachable = true;
449 for (MachineBasicBlock::const_succ_iterator SuI = MBB->succ_begin(),
450 SuE = MBB->succ_end(); SuI != SuE; ++SuI)
455 void MachineVerifier::visitMachineFunctionBefore() {
456 lastIndex = SlotIndex();
457 regsReserved = MRI->getReservedRegs();
459 // A sub-register of a reserved register is also reserved
460 for (int Reg = regsReserved.find_first(); Reg>=0;
461 Reg = regsReserved.find_next(Reg)) {
462 for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs) {
463 // FIXME: This should probably be:
464 // assert(regsReserved.test(*SubRegs) && "Non-reserved sub-register");
465 regsReserved.set(*SubRegs);
469 markReachable(&MF->front());
471 // Build a set of the basic blocks in the function.
472 FunctionBlocks.clear();
473 for (MachineFunction::const_iterator
474 I = MF->begin(), E = MF->end(); I != E; ++I) {
475 FunctionBlocks.insert(I);
476 BBInfo &MInfo = MBBInfoMap[I];
478 MInfo.Preds.insert(I->pred_begin(), I->pred_end());
479 if (MInfo.Preds.size() != I->pred_size())
480 report("MBB has duplicate entries in its predecessor list.", I);
482 MInfo.Succs.insert(I->succ_begin(), I->succ_end());
483 if (MInfo.Succs.size() != I->succ_size())
484 report("MBB has duplicate entries in its successor list.", I);
487 // Check that the register use lists are sane.
488 MRI->verifyUseLists();
493 // Does iterator point to a and b as the first two elements?
494 static bool matchPair(MachineBasicBlock::const_succ_iterator i,
495 const MachineBasicBlock *a, const MachineBasicBlock *b) {
504 MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
505 FirstTerminator = nullptr;
508 // If this block has allocatable physical registers live-in, check that
509 // it is an entry block or landing pad.
510 for (MachineBasicBlock::livein_iterator LI = MBB->livein_begin(),
511 LE = MBB->livein_end();
514 if (isAllocatable(reg) && !MBB->isLandingPad() &&
515 MBB != MBB->getParent()->begin()) {
516 report("MBB has allocable live-in, but isn't entry or landing-pad.", MBB);
521 // Count the number of landing pad successors.
522 SmallPtrSet<MachineBasicBlock*, 4> LandingPadSuccs;
523 for (MachineBasicBlock::const_succ_iterator I = MBB->succ_begin(),
524 E = MBB->succ_end(); I != E; ++I) {
525 if ((*I)->isLandingPad())
526 LandingPadSuccs.insert(*I);
527 if (!FunctionBlocks.count(*I))
528 report("MBB has successor that isn't part of the function.", MBB);
529 if (!MBBInfoMap[*I].Preds.count(MBB)) {
530 report("Inconsistent CFG", MBB);
531 *OS << "MBB is not in the predecessor list of the successor BB#"
532 << (*I)->getNumber() << ".\n";
536 // Check the predecessor list.
537 for (MachineBasicBlock::const_pred_iterator I = MBB->pred_begin(),
538 E = MBB->pred_end(); I != E; ++I) {
539 if (!FunctionBlocks.count(*I))
540 report("MBB has predecessor that isn't part of the function.", MBB);
541 if (!MBBInfoMap[*I].Succs.count(MBB)) {
542 report("Inconsistent CFG", MBB);
543 *OS << "MBB is not in the successor list of the predecessor BB#"
544 << (*I)->getNumber() << ".\n";
548 const MCAsmInfo *AsmInfo = TM->getMCAsmInfo();
549 const BasicBlock *BB = MBB->getBasicBlock();
550 if (LandingPadSuccs.size() > 1 &&
552 AsmInfo->getExceptionHandlingType() == ExceptionHandling::SjLj &&
553 BB && isa<SwitchInst>(BB->getTerminator())))
554 report("MBB has more than one landing pad successor", MBB);
556 // Call AnalyzeBranch. If it succeeds, there several more conditions to check.
557 MachineBasicBlock *TBB = nullptr, *FBB = nullptr;
558 SmallVector<MachineOperand, 4> Cond;
559 if (!TII->AnalyzeBranch(*const_cast<MachineBasicBlock *>(MBB),
561 // Ok, AnalyzeBranch thinks it knows what's going on with this block. Let's
562 // check whether its answers match up with reality.
564 // Block falls through to its successor.
565 MachineFunction::const_iterator MBBI = MBB;
567 if (MBBI == MF->end()) {
568 // It's possible that the block legitimately ends with a noreturn
569 // call or an unreachable, in which case it won't actually fall
570 // out the bottom of the function.
571 } else if (MBB->succ_size() == LandingPadSuccs.size()) {
572 // It's possible that the block legitimately ends with a noreturn
573 // call or an unreachable, in which case it won't actuall fall
575 } else if (MBB->succ_size() != 1+LandingPadSuccs.size()) {
576 report("MBB exits via unconditional fall-through but doesn't have "
577 "exactly one CFG successor!", MBB);
578 } else if (!MBB->isSuccessor(MBBI)) {
579 report("MBB exits via unconditional fall-through but its successor "
580 "differs from its CFG successor!", MBB);
582 if (!MBB->empty() && getBundleStart(&MBB->back())->isBarrier() &&
583 !TII->isPredicated(getBundleStart(&MBB->back()))) {
584 report("MBB exits via unconditional fall-through but ends with a "
585 "barrier instruction!", MBB);
588 report("MBB exits via unconditional fall-through but has a condition!",
591 } else if (TBB && !FBB && Cond.empty()) {
592 // Block unconditionally branches somewhere.
593 if (MBB->succ_size() != 1+LandingPadSuccs.size()) {
594 report("MBB exits via unconditional branch but doesn't have "
595 "exactly one CFG successor!", MBB);
596 } else if (!MBB->isSuccessor(TBB)) {
597 report("MBB exits via unconditional branch but the CFG "
598 "successor doesn't match the actual successor!", MBB);
601 report("MBB exits via unconditional branch but doesn't contain "
602 "any instructions!", MBB);
603 } else if (!getBundleStart(&MBB->back())->isBarrier()) {
604 report("MBB exits via unconditional branch but doesn't end with a "
605 "barrier instruction!", MBB);
606 } else if (!getBundleStart(&MBB->back())->isTerminator()) {
607 report("MBB exits via unconditional branch but the branch isn't a "
608 "terminator instruction!", MBB);
610 } else if (TBB && !FBB && !Cond.empty()) {
611 // Block conditionally branches somewhere, otherwise falls through.
612 MachineFunction::const_iterator MBBI = MBB;
614 if (MBBI == MF->end()) {
615 report("MBB conditionally falls through out of function!", MBB);
616 } else if (MBB->succ_size() == 1) {
617 // A conditional branch with only one successor is weird, but allowed.
619 report("MBB exits via conditional branch/fall-through but only has "
620 "one CFG successor!", MBB);
621 else if (TBB != *MBB->succ_begin())
622 report("MBB exits via conditional branch/fall-through but the CFG "
623 "successor don't match the actual successor!", MBB);
624 } else if (MBB->succ_size() != 2) {
625 report("MBB exits via conditional branch/fall-through but doesn't have "
626 "exactly two CFG successors!", MBB);
627 } else if (!matchPair(MBB->succ_begin(), TBB, MBBI)) {
628 report("MBB exits via conditional branch/fall-through but the CFG "
629 "successors don't match the actual successors!", MBB);
632 report("MBB exits via conditional branch/fall-through but doesn't "
633 "contain any instructions!", MBB);
634 } else if (getBundleStart(&MBB->back())->isBarrier()) {
635 report("MBB exits via conditional branch/fall-through but ends with a "
636 "barrier instruction!", MBB);
637 } else if (!getBundleStart(&MBB->back())->isTerminator()) {
638 report("MBB exits via conditional branch/fall-through but the branch "
639 "isn't a terminator instruction!", MBB);
641 } else if (TBB && FBB) {
642 // Block conditionally branches somewhere, otherwise branches
644 if (MBB->succ_size() == 1) {
645 // A conditional branch with only one successor is weird, but allowed.
647 report("MBB exits via conditional branch/branch through but only has "
648 "one CFG successor!", MBB);
649 else if (TBB != *MBB->succ_begin())
650 report("MBB exits via conditional branch/branch through but the CFG "
651 "successor don't match the actual successor!", MBB);
652 } else if (MBB->succ_size() != 2) {
653 report("MBB exits via conditional branch/branch but doesn't have "
654 "exactly two CFG successors!", MBB);
655 } else if (!matchPair(MBB->succ_begin(), TBB, FBB)) {
656 report("MBB exits via conditional branch/branch but the CFG "
657 "successors don't match the actual successors!", MBB);
660 report("MBB exits via conditional branch/branch but doesn't "
661 "contain any instructions!", MBB);
662 } else if (!getBundleStart(&MBB->back())->isBarrier()) {
663 report("MBB exits via conditional branch/branch but doesn't end with a "
664 "barrier instruction!", MBB);
665 } else if (!getBundleStart(&MBB->back())->isTerminator()) {
666 report("MBB exits via conditional branch/branch but the branch "
667 "isn't a terminator instruction!", MBB);
670 report("MBB exits via conditinal branch/branch but there's no "
674 report("AnalyzeBranch returned invalid data!", MBB);
679 for (MachineBasicBlock::livein_iterator I = MBB->livein_begin(),
680 E = MBB->livein_end(); I != E; ++I) {
681 if (!TargetRegisterInfo::isPhysicalRegister(*I)) {
682 report("MBB live-in list contains non-physical register", MBB);
685 for (MCSubRegIterator SubRegs(*I, TRI, /*IncludeSelf=*/true);
686 SubRegs.isValid(); ++SubRegs)
687 regsLive.insert(*SubRegs);
689 regsLiveInButUnused = regsLive;
691 const MachineFrameInfo *MFI = MF->getFrameInfo();
692 assert(MFI && "Function has no frame info");
693 BitVector PR = MFI->getPristineRegs(MBB);
694 for (int I = PR.find_first(); I>0; I = PR.find_next(I)) {
695 for (MCSubRegIterator SubRegs(I, TRI, /*IncludeSelf=*/true);
696 SubRegs.isValid(); ++SubRegs)
697 regsLive.insert(*SubRegs);
704 lastIndex = Indexes->getMBBStartIdx(MBB);
707 // This function gets called for all bundle headers, including normal
708 // stand-alone unbundled instructions.
709 void MachineVerifier::visitMachineBundleBefore(const MachineInstr *MI) {
710 if (Indexes && Indexes->hasIndex(MI)) {
711 SlotIndex idx = Indexes->getInstructionIndex(MI);
712 if (!(idx > lastIndex)) {
713 report("Instruction index out of order", MI);
714 *OS << "Last instruction was at " << lastIndex << '\n';
719 // Ensure non-terminators don't follow terminators.
720 // Ignore predicated terminators formed by if conversion.
721 // FIXME: If conversion shouldn't need to violate this rule.
722 if (MI->isTerminator() && !TII->isPredicated(MI)) {
723 if (!FirstTerminator)
724 FirstTerminator = MI;
725 } else if (FirstTerminator) {
726 report("Non-terminator instruction after the first terminator", MI);
727 *OS << "First terminator was:\t" << *FirstTerminator;
731 // The operands on an INLINEASM instruction must follow a template.
732 // Verify that the flag operands make sense.
733 void MachineVerifier::verifyInlineAsm(const MachineInstr *MI) {
734 // The first two operands on INLINEASM are the asm string and global flags.
735 if (MI->getNumOperands() < 2) {
736 report("Too few operands on inline asm", MI);
739 if (!MI->getOperand(0).isSymbol())
740 report("Asm string must be an external symbol", MI);
741 if (!MI->getOperand(1).isImm())
742 report("Asm flags must be an immediate", MI);
743 // Allowed flags are Extra_HasSideEffects = 1, Extra_IsAlignStack = 2,
744 // Extra_AsmDialect = 4, Extra_MayLoad = 8, and Extra_MayStore = 16.
745 if (!isUInt<5>(MI->getOperand(1).getImm()))
746 report("Unknown asm flags", &MI->getOperand(1), 1);
748 assert(InlineAsm::MIOp_FirstOperand == 2 && "Asm format changed");
750 unsigned OpNo = InlineAsm::MIOp_FirstOperand;
752 for (unsigned e = MI->getNumOperands(); OpNo < e; OpNo += NumOps) {
753 const MachineOperand &MO = MI->getOperand(OpNo);
754 // There may be implicit ops after the fixed operands.
757 NumOps = 1 + InlineAsm::getNumOperandRegisters(MO.getImm());
760 if (OpNo > MI->getNumOperands())
761 report("Missing operands in last group", MI);
763 // An optional MDNode follows the groups.
764 if (OpNo < MI->getNumOperands() && MI->getOperand(OpNo).isMetadata())
767 // All trailing operands must be implicit registers.
768 for (unsigned e = MI->getNumOperands(); OpNo < e; ++OpNo) {
769 const MachineOperand &MO = MI->getOperand(OpNo);
770 if (!MO.isReg() || !MO.isImplicit())
771 report("Expected implicit register after groups", &MO, OpNo);
775 void MachineVerifier::visitMachineInstrBefore(const MachineInstr *MI) {
776 const MCInstrDesc &MCID = MI->getDesc();
777 if (MI->getNumOperands() < MCID.getNumOperands()) {
778 report("Too few operands", MI);
779 *OS << MCID.getNumOperands() << " operands expected, but "
780 << MI->getNumOperands() << " given.\n";
783 // Check the tied operands.
784 if (MI->isInlineAsm())
787 // Check the MachineMemOperands for basic consistency.
788 for (MachineInstr::mmo_iterator I = MI->memoperands_begin(),
789 E = MI->memoperands_end(); I != E; ++I) {
790 if ((*I)->isLoad() && !MI->mayLoad())
791 report("Missing mayLoad flag", MI);
792 if ((*I)->isStore() && !MI->mayStore())
793 report("Missing mayStore flag", MI);
796 // Debug values must not have a slot index.
797 // Other instructions must have one, unless they are inside a bundle.
799 bool mapped = !LiveInts->isNotInMIMap(MI);
800 if (MI->isDebugValue()) {
802 report("Debug instruction has a slot index", MI);
803 } else if (MI->isInsideBundle()) {
805 report("Instruction inside bundle has a slot index", MI);
808 report("Missing slot index", MI);
813 if (!TII->verifyInstruction(MI, ErrorInfo))
814 report(ErrorInfo.data(), MI);
818 MachineVerifier::visitMachineOperand(const MachineOperand *MO, unsigned MONum) {
819 const MachineInstr *MI = MO->getParent();
820 const MCInstrDesc &MCID = MI->getDesc();
822 // The first MCID.NumDefs operands must be explicit register defines
823 if (MONum < MCID.getNumDefs()) {
824 const MCOperandInfo &MCOI = MCID.OpInfo[MONum];
826 report("Explicit definition must be a register", MO, MONum);
827 else if (!MO->isDef() && !MCOI.isOptionalDef())
828 report("Explicit definition marked as use", MO, MONum);
829 else if (MO->isImplicit())
830 report("Explicit definition marked as implicit", MO, MONum);
831 } else if (MONum < MCID.getNumOperands()) {
832 const MCOperandInfo &MCOI = MCID.OpInfo[MONum];
833 // Don't check if it's the last operand in a variadic instruction. See,
834 // e.g., LDM_RET in the arm back end.
836 !(MI->isVariadic() && MONum == MCID.getNumOperands()-1)) {
837 if (MO->isDef() && !MCOI.isOptionalDef())
838 report("Explicit operand marked as def", MO, MONum);
839 if (MO->isImplicit())
840 report("Explicit operand marked as implicit", MO, MONum);
843 int TiedTo = MCID.getOperandConstraint(MONum, MCOI::TIED_TO);
846 report("Tied use must be a register", MO, MONum);
847 else if (!MO->isTied())
848 report("Operand should be tied", MO, MONum);
849 else if (unsigned(TiedTo) != MI->findTiedOperandIdx(MONum))
850 report("Tied def doesn't match MCInstrDesc", MO, MONum);
851 } else if (MO->isReg() && MO->isTied())
852 report("Explicit operand should not be tied", MO, MONum);
854 // ARM adds %reg0 operands to indicate predicates. We'll allow that.
855 if (MO->isReg() && !MO->isImplicit() && !MI->isVariadic() && MO->getReg())
856 report("Extra explicit operand on non-variadic instruction", MO, MONum);
859 switch (MO->getType()) {
860 case MachineOperand::MO_Register: {
861 const unsigned Reg = MO->getReg();
864 if (MRI->tracksLiveness() && !MI->isDebugValue())
865 checkLiveness(MO, MONum);
867 // Verify the consistency of tied operands.
869 unsigned OtherIdx = MI->findTiedOperandIdx(MONum);
870 const MachineOperand &OtherMO = MI->getOperand(OtherIdx);
871 if (!OtherMO.isReg())
872 report("Must be tied to a register", MO, MONum);
873 if (!OtherMO.isTied())
874 report("Missing tie flags on tied operand", MO, MONum);
875 if (MI->findTiedOperandIdx(OtherIdx) != MONum)
876 report("Inconsistent tie links", MO, MONum);
877 if (MONum < MCID.getNumDefs()) {
878 if (OtherIdx < MCID.getNumOperands()) {
879 if (-1 == MCID.getOperandConstraint(OtherIdx, MCOI::TIED_TO))
880 report("Explicit def tied to explicit use without tie constraint",
883 if (!OtherMO.isImplicit())
884 report("Explicit def should be tied to implicit use", MO, MONum);
889 // Verify two-address constraints after leaving SSA form.
891 if (!MRI->isSSA() && MO->isUse() &&
892 MI->isRegTiedToDefOperand(MONum, &DefIdx) &&
893 Reg != MI->getOperand(DefIdx).getReg())
894 report("Two-address instruction operands must be identical", MO, MONum);
896 // Check register classes.
897 if (MONum < MCID.getNumOperands() && !MO->isImplicit()) {
898 unsigned SubIdx = MO->getSubReg();
900 if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
902 report("Illegal subregister index for physical register", MO, MONum);
905 if (const TargetRegisterClass *DRC =
906 TII->getRegClass(MCID, MONum, TRI, *MF)) {
907 if (!DRC->contains(Reg)) {
908 report("Illegal physical register for instruction", MO, MONum);
909 *OS << TRI->getName(Reg) << " is not a "
910 << DRC->getName() << " register.\n";
915 const TargetRegisterClass *RC = MRI->getRegClass(Reg);
917 const TargetRegisterClass *SRC =
918 TRI->getSubClassWithSubReg(RC, SubIdx);
920 report("Invalid subregister index for virtual register", MO, MONum);
921 *OS << "Register class " << RC->getName()
922 << " does not support subreg index " << SubIdx << "\n";
926 report("Invalid register class for subregister index", MO, MONum);
927 *OS << "Register class " << RC->getName()
928 << " does not fully support subreg index " << SubIdx << "\n";
932 if (const TargetRegisterClass *DRC =
933 TII->getRegClass(MCID, MONum, TRI, *MF)) {
935 const TargetRegisterClass *SuperRC =
936 TRI->getLargestLegalSuperClass(RC);
938 report("No largest legal super class exists.", MO, MONum);
941 DRC = TRI->getMatchingSuperRegClass(SuperRC, DRC, SubIdx);
943 report("No matching super-reg register class.", MO, MONum);
947 if (!RC->hasSuperClassEq(DRC)) {
948 report("Illegal virtual register for instruction", MO, MONum);
949 *OS << "Expected a " << DRC->getName() << " register, but got a "
950 << RC->getName() << " register\n";
958 case MachineOperand::MO_RegisterMask:
959 regMasks.push_back(MO->getRegMask());
962 case MachineOperand::MO_MachineBasicBlock:
963 if (MI->isPHI() && !MO->getMBB()->isSuccessor(MI->getParent()))
964 report("PHI operand is not in the CFG", MO, MONum);
967 case MachineOperand::MO_FrameIndex:
968 if (LiveStks && LiveStks->hasInterval(MO->getIndex()) &&
969 LiveInts && !LiveInts->isNotInMIMap(MI)) {
970 LiveInterval &LI = LiveStks->getInterval(MO->getIndex());
971 SlotIndex Idx = LiveInts->getInstructionIndex(MI);
972 if (MI->mayLoad() && !LI.liveAt(Idx.getRegSlot(true))) {
973 report("Instruction loads from dead spill slot", MO, MONum);
974 *OS << "Live stack: " << LI << '\n';
976 if (MI->mayStore() && !LI.liveAt(Idx.getRegSlot())) {
977 report("Instruction stores to dead spill slot", MO, MONum);
978 *OS << "Live stack: " << LI << '\n';
988 void MachineVerifier::checkLiveness(const MachineOperand *MO, unsigned MONum) {
989 const MachineInstr *MI = MO->getParent();
990 const unsigned Reg = MO->getReg();
992 // Both use and def operands can read a register.
993 if (MO->readsReg()) {
994 regsLiveInButUnused.erase(Reg);
997 addRegWithSubRegs(regsKilled, Reg);
999 // Check that LiveVars knows this kill.
1000 if (LiveVars && TargetRegisterInfo::isVirtualRegister(Reg) &&
1002 LiveVariables::VarInfo &VI = LiveVars->getVarInfo(Reg);
1003 if (std::find(VI.Kills.begin(), VI.Kills.end(), MI) == VI.Kills.end())
1004 report("Kill missing from LiveVariables", MO, MONum);
1007 // Check LiveInts liveness and kill.
1008 if (LiveInts && !LiveInts->isNotInMIMap(MI)) {
1009 SlotIndex UseIdx = LiveInts->getInstructionIndex(MI);
1010 // Check the cached regunit intervals.
1011 if (TargetRegisterInfo::isPhysicalRegister(Reg) && !isReserved(Reg)) {
1012 for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units) {
1013 if (const LiveRange *LR = LiveInts->getCachedRegUnit(*Units)) {
1014 LiveQueryResult LRQ = LR->Query(UseIdx);
1015 if (!LRQ.valueIn()) {
1016 report("No live segment at use", MO, MONum);
1017 *OS << UseIdx << " is not live in " << PrintRegUnit(*Units, TRI)
1018 << ' ' << *LR << '\n';
1020 if (MO->isKill() && !LRQ.isKill()) {
1021 report("Live range continues after kill flag", MO, MONum);
1022 *OS << PrintRegUnit(*Units, TRI) << ' ' << *LR << '\n';
1028 if (TargetRegisterInfo::isVirtualRegister(Reg)) {
1029 if (LiveInts->hasInterval(Reg)) {
1030 // This is a virtual register interval.
1031 const LiveInterval &LI = LiveInts->getInterval(Reg);
1032 LiveQueryResult LRQ = LI.Query(UseIdx);
1033 if (!LRQ.valueIn()) {
1034 report("No live segment at use", MO, MONum);
1035 *OS << UseIdx << " is not live in " << LI << '\n';
1037 // Check for extra kill flags.
1038 // Note that we allow missing kill flags for now.
1039 if (MO->isKill() && !LRQ.isKill()) {
1040 report("Live range continues after kill flag", MO, MONum);
1041 *OS << "Live range: " << LI << '\n';
1044 report("Virtual register has no live interval", MO, MONum);
1049 // Use of a dead register.
1050 if (!regsLive.count(Reg)) {
1051 if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
1052 // Reserved registers may be used even when 'dead'.
1053 if (!isReserved(Reg))
1054 report("Using an undefined physical register", MO, MONum);
1055 } else if (MRI->def_empty(Reg)) {
1056 report("Reading virtual register without a def", MO, MONum);
1058 BBInfo &MInfo = MBBInfoMap[MI->getParent()];
1059 // We don't know which virtual registers are live in, so only complain
1060 // if vreg was killed in this MBB. Otherwise keep track of vregs that
1061 // must be live in. PHI instructions are handled separately.
1062 if (MInfo.regsKilled.count(Reg))
1063 report("Using a killed virtual register", MO, MONum);
1064 else if (!MI->isPHI())
1065 MInfo.vregsLiveIn.insert(std::make_pair(Reg, MI));
1071 // Register defined.
1072 // TODO: verify that earlyclobber ops are not used.
1074 addRegWithSubRegs(regsDead, Reg);
1076 addRegWithSubRegs(regsDefined, Reg);
1079 if (MRI->isSSA() && TargetRegisterInfo::isVirtualRegister(Reg) &&
1080 std::next(MRI->def_begin(Reg)) != MRI->def_end())
1081 report("Multiple virtual register defs in SSA form", MO, MONum);
1083 // Check LiveInts for a live segment, but only for virtual registers.
1084 if (LiveInts && TargetRegisterInfo::isVirtualRegister(Reg) &&
1085 !LiveInts->isNotInMIMap(MI)) {
1086 SlotIndex DefIdx = LiveInts->getInstructionIndex(MI);
1087 DefIdx = DefIdx.getRegSlot(MO->isEarlyClobber());
1088 if (LiveInts->hasInterval(Reg)) {
1089 const LiveInterval &LI = LiveInts->getInterval(Reg);
1090 if (const VNInfo *VNI = LI.getVNInfoAt(DefIdx)) {
1091 assert(VNI && "NULL valno is not allowed");
1092 if (VNI->def != DefIdx) {
1093 report("Inconsistent valno->def", MO, MONum);
1094 *OS << "Valno " << VNI->id << " is not defined at "
1095 << DefIdx << " in " << LI << '\n';
1098 report("No live segment at def", MO, MONum);
1099 *OS << DefIdx << " is not live in " << LI << '\n';
1101 // Check that, if the dead def flag is present, LiveInts agree.
1103 LiveQueryResult LRQ = LI.Query(DefIdx);
1104 if (!LRQ.isDeadDef()) {
1105 report("Live range continues after dead def flag", MO, MONum);
1106 *OS << "Live range: " << LI << '\n';
1110 report("Virtual register has no Live interval", MO, MONum);
1116 void MachineVerifier::visitMachineInstrAfter(const MachineInstr *MI) {
1119 // This function gets called after visiting all instructions in a bundle. The
1120 // argument points to the bundle header.
1121 // Normal stand-alone instructions are also considered 'bundles', and this
1122 // function is called for all of them.
1123 void MachineVerifier::visitMachineBundleAfter(const MachineInstr *MI) {
1124 BBInfo &MInfo = MBBInfoMap[MI->getParent()];
1125 set_union(MInfo.regsKilled, regsKilled);
1126 set_subtract(regsLive, regsKilled); regsKilled.clear();
1127 // Kill any masked registers.
1128 while (!regMasks.empty()) {
1129 const uint32_t *Mask = regMasks.pop_back_val();
1130 for (RegSet::iterator I = regsLive.begin(), E = regsLive.end(); I != E; ++I)
1131 if (TargetRegisterInfo::isPhysicalRegister(*I) &&
1132 MachineOperand::clobbersPhysReg(Mask, *I))
1133 regsDead.push_back(*I);
1135 set_subtract(regsLive, regsDead); regsDead.clear();
1136 set_union(regsLive, regsDefined); regsDefined.clear();
1140 MachineVerifier::visitMachineBasicBlockAfter(const MachineBasicBlock *MBB) {
1141 MBBInfoMap[MBB].regsLiveOut = regsLive;
1145 SlotIndex stop = Indexes->getMBBEndIdx(MBB);
1146 if (!(stop > lastIndex)) {
1147 report("Block ends before last instruction index", MBB);
1148 *OS << "Block ends at " << stop
1149 << " last instruction was at " << lastIndex << '\n';
1155 // Calculate the largest possible vregsPassed sets. These are the registers that
1156 // can pass through an MBB live, but may not be live every time. It is assumed
1157 // that all vregsPassed sets are empty before the call.
1158 void MachineVerifier::calcRegsPassed() {
1159 // First push live-out regs to successors' vregsPassed. Remember the MBBs that
1160 // have any vregsPassed.
1161 SmallPtrSet<const MachineBasicBlock*, 8> todo;
1162 for (MachineFunction::const_iterator MFI = MF->begin(), MFE = MF->end();
1163 MFI != MFE; ++MFI) {
1164 const MachineBasicBlock &MBB(*MFI);
1165 BBInfo &MInfo = MBBInfoMap[&MBB];
1166 if (!MInfo.reachable)
1168 for (MachineBasicBlock::const_succ_iterator SuI = MBB.succ_begin(),
1169 SuE = MBB.succ_end(); SuI != SuE; ++SuI) {
1170 BBInfo &SInfo = MBBInfoMap[*SuI];
1171 if (SInfo.addPassed(MInfo.regsLiveOut))
1176 // Iteratively push vregsPassed to successors. This will converge to the same
1177 // final state regardless of DenseSet iteration order.
1178 while (!todo.empty()) {
1179 const MachineBasicBlock *MBB = *todo.begin();
1181 BBInfo &MInfo = MBBInfoMap[MBB];
1182 for (MachineBasicBlock::const_succ_iterator SuI = MBB->succ_begin(),
1183 SuE = MBB->succ_end(); SuI != SuE; ++SuI) {
1186 BBInfo &SInfo = MBBInfoMap[*SuI];
1187 if (SInfo.addPassed(MInfo.vregsPassed))
1193 // Calculate the set of virtual registers that must be passed through each basic
1194 // block in order to satisfy the requirements of successor blocks. This is very
1195 // similar to calcRegsPassed, only backwards.
1196 void MachineVerifier::calcRegsRequired() {
1197 // First push live-in regs to predecessors' vregsRequired.
1198 SmallPtrSet<const MachineBasicBlock*, 8> todo;
1199 for (MachineFunction::const_iterator MFI = MF->begin(), MFE = MF->end();
1200 MFI != MFE; ++MFI) {
1201 const MachineBasicBlock &MBB(*MFI);
1202 BBInfo &MInfo = MBBInfoMap[&MBB];
1203 for (MachineBasicBlock::const_pred_iterator PrI = MBB.pred_begin(),
1204 PrE = MBB.pred_end(); PrI != PrE; ++PrI) {
1205 BBInfo &PInfo = MBBInfoMap[*PrI];
1206 if (PInfo.addRequired(MInfo.vregsLiveIn))
1211 // Iteratively push vregsRequired to predecessors. This will converge to the
1212 // same final state regardless of DenseSet iteration order.
1213 while (!todo.empty()) {
1214 const MachineBasicBlock *MBB = *todo.begin();
1216 BBInfo &MInfo = MBBInfoMap[MBB];
1217 for (MachineBasicBlock::const_pred_iterator PrI = MBB->pred_begin(),
1218 PrE = MBB->pred_end(); PrI != PrE; ++PrI) {
1221 BBInfo &SInfo = MBBInfoMap[*PrI];
1222 if (SInfo.addRequired(MInfo.vregsRequired))
1228 // Check PHI instructions at the beginning of MBB. It is assumed that
1229 // calcRegsPassed has been run so BBInfo::isLiveOut is valid.
1230 void MachineVerifier::checkPHIOps(const MachineBasicBlock *MBB) {
1231 SmallPtrSet<const MachineBasicBlock*, 8> seen;
1232 for (MachineBasicBlock::const_iterator BBI = MBB->begin(), BBE = MBB->end();
1233 BBI != BBE && BBI->isPHI(); ++BBI) {
1236 for (unsigned i = 1, e = BBI->getNumOperands(); i != e; i += 2) {
1237 unsigned Reg = BBI->getOperand(i).getReg();
1238 const MachineBasicBlock *Pre = BBI->getOperand(i + 1).getMBB();
1239 if (!Pre->isSuccessor(MBB))
1242 BBInfo &PrInfo = MBBInfoMap[Pre];
1243 if (PrInfo.reachable && !PrInfo.isLiveOut(Reg))
1244 report("PHI operand is not live-out from predecessor",
1245 &BBI->getOperand(i), i);
1248 // Did we see all predecessors?
1249 for (MachineBasicBlock::const_pred_iterator PrI = MBB->pred_begin(),
1250 PrE = MBB->pred_end(); PrI != PrE; ++PrI) {
1251 if (!seen.count(*PrI)) {
1252 report("Missing PHI operand", BBI);
1253 *OS << "BB#" << (*PrI)->getNumber()
1254 << " is a predecessor according to the CFG.\n";
1260 void MachineVerifier::visitMachineFunctionAfter() {
1263 for (MachineFunction::const_iterator MFI = MF->begin(), MFE = MF->end();
1264 MFI != MFE; ++MFI) {
1265 BBInfo &MInfo = MBBInfoMap[MFI];
1267 // Skip unreachable MBBs.
1268 if (!MInfo.reachable)
1274 // Now check liveness info if available
1277 // Check for killed virtual registers that should be live out.
1278 for (MachineFunction::const_iterator MFI = MF->begin(), MFE = MF->end();
1279 MFI != MFE; ++MFI) {
1280 BBInfo &MInfo = MBBInfoMap[MFI];
1281 for (RegSet::iterator
1282 I = MInfo.vregsRequired.begin(), E = MInfo.vregsRequired.end(); I != E;
1284 if (MInfo.regsKilled.count(*I)) {
1285 report("Virtual register killed in block, but needed live out.", MFI);
1286 *OS << "Virtual register " << PrintReg(*I)
1287 << " is used after the block.\n";
1292 BBInfo &MInfo = MBBInfoMap[&MF->front()];
1293 for (RegSet::iterator
1294 I = MInfo.vregsRequired.begin(), E = MInfo.vregsRequired.end(); I != E;
1296 report("Virtual register def doesn't dominate all uses.",
1297 MRI->getVRegDef(*I));
1301 verifyLiveVariables();
1303 verifyLiveIntervals();
1306 void MachineVerifier::verifyLiveVariables() {
1307 assert(LiveVars && "Don't call verifyLiveVariables without LiveVars");
1308 for (unsigned i = 0, e = MRI->getNumVirtRegs(); i != e; ++i) {
1309 unsigned Reg = TargetRegisterInfo::index2VirtReg(i);
1310 LiveVariables::VarInfo &VI = LiveVars->getVarInfo(Reg);
1311 for (MachineFunction::const_iterator MFI = MF->begin(), MFE = MF->end();
1312 MFI != MFE; ++MFI) {
1313 BBInfo &MInfo = MBBInfoMap[MFI];
1315 // Our vregsRequired should be identical to LiveVariables' AliveBlocks
1316 if (MInfo.vregsRequired.count(Reg)) {
1317 if (!VI.AliveBlocks.test(MFI->getNumber())) {
1318 report("LiveVariables: Block missing from AliveBlocks", MFI);
1319 *OS << "Virtual register " << PrintReg(Reg)
1320 << " must be live through the block.\n";
1323 if (VI.AliveBlocks.test(MFI->getNumber())) {
1324 report("LiveVariables: Block should not be in AliveBlocks", MFI);
1325 *OS << "Virtual register " << PrintReg(Reg)
1326 << " is not needed live through the block.\n";
1333 void MachineVerifier::verifyLiveIntervals() {
1334 assert(LiveInts && "Don't call verifyLiveIntervals without LiveInts");
1335 for (unsigned i = 0, e = MRI->getNumVirtRegs(); i != e; ++i) {
1336 unsigned Reg = TargetRegisterInfo::index2VirtReg(i);
1338 // Spilling and splitting may leave unused registers around. Skip them.
1339 if (MRI->reg_nodbg_empty(Reg))
1342 if (!LiveInts->hasInterval(Reg)) {
1343 report("Missing live interval for virtual register", MF);
1344 *OS << PrintReg(Reg, TRI) << " still has defs or uses\n";
1348 const LiveInterval &LI = LiveInts->getInterval(Reg);
1349 assert(Reg == LI.reg && "Invalid reg to interval mapping");
1350 verifyLiveInterval(LI);
1353 // Verify all the cached regunit intervals.
1354 for (unsigned i = 0, e = TRI->getNumRegUnits(); i != e; ++i)
1355 if (const LiveRange *LR = LiveInts->getCachedRegUnit(i))
1356 verifyLiveRange(*LR, i);
1359 void MachineVerifier::verifyLiveRangeValue(const LiveRange &LR,
1362 if (VNI->isUnused())
1365 const VNInfo *DefVNI = LR.getVNInfoAt(VNI->def);
1368 report("Valno not live at def and not marked unused", MF, LR);
1369 *OS << "Valno #" << VNI->id << '\n';
1373 if (DefVNI != VNI) {
1374 report("Live segment at def has different valno", MF, LR);
1375 *OS << "Valno #" << VNI->id << " is defined at " << VNI->def
1376 << " where valno #" << DefVNI->id << " is live\n";
1380 const MachineBasicBlock *MBB = LiveInts->getMBBFromIndex(VNI->def);
1382 report("Invalid definition index", MF, LR);
1383 *OS << "Valno #" << VNI->id << " is defined at " << VNI->def
1384 << " in " << LR << '\n';
1388 if (VNI->isPHIDef()) {
1389 if (VNI->def != LiveInts->getMBBStartIdx(MBB)) {
1390 report("PHIDef value is not defined at MBB start", MBB, LR);
1391 *OS << "Valno #" << VNI->id << " is defined at " << VNI->def
1392 << ", not at the beginning of BB#" << MBB->getNumber() << '\n';
1398 const MachineInstr *MI = LiveInts->getInstructionFromIndex(VNI->def);
1400 report("No instruction at def index", MBB, LR);
1401 *OS << "Valno #" << VNI->id << " is defined at " << VNI->def << '\n';
1406 bool hasDef = false;
1407 bool isEarlyClobber = false;
1408 for (ConstMIBundleOperands MOI(MI); MOI.isValid(); ++MOI) {
1409 if (!MOI->isReg() || !MOI->isDef())
1411 if (TargetRegisterInfo::isVirtualRegister(Reg)) {
1412 if (MOI->getReg() != Reg)
1415 if (!TargetRegisterInfo::isPhysicalRegister(MOI->getReg()) ||
1416 !TRI->hasRegUnit(MOI->getReg(), Reg))
1420 if (MOI->isEarlyClobber())
1421 isEarlyClobber = true;
1425 report("Defining instruction does not modify register", MI);
1426 *OS << "Valno #" << VNI->id << " in " << LR << '\n';
1429 // Early clobber defs begin at USE slots, but other defs must begin at
1431 if (isEarlyClobber) {
1432 if (!VNI->def.isEarlyClobber()) {
1433 report("Early clobber def must be at an early-clobber slot", MBB, LR);
1434 *OS << "Valno #" << VNI->id << " is defined at " << VNI->def << '\n';
1436 } else if (!VNI->def.isRegister()) {
1437 report("Non-PHI, non-early clobber def must be at a register slot",
1439 *OS << "Valno #" << VNI->id << " is defined at " << VNI->def << '\n';
1444 void MachineVerifier::verifyLiveRangeSegment(const LiveRange &LR,
1445 const LiveRange::const_iterator I,
1447 const LiveRange::Segment &S = *I;
1448 const VNInfo *VNI = S.valno;
1449 assert(VNI && "Live segment has no valno");
1451 if (VNI->id >= LR.getNumValNums() || VNI != LR.getValNumInfo(VNI->id)) {
1452 report("Foreign valno in live segment", MF, LR);
1453 *OS << S << " has a bad valno\n";
1456 if (VNI->isUnused()) {
1457 report("Live segment valno is marked unused", MF, LR);
1461 const MachineBasicBlock *MBB = LiveInts->getMBBFromIndex(S.start);
1463 report("Bad start of live segment, no basic block", MF, LR);
1467 SlotIndex MBBStartIdx = LiveInts->getMBBStartIdx(MBB);
1468 if (S.start != MBBStartIdx && S.start != VNI->def) {
1469 report("Live segment must begin at MBB entry or valno def", MBB, LR);
1473 const MachineBasicBlock *EndMBB =
1474 LiveInts->getMBBFromIndex(S.end.getPrevSlot());
1476 report("Bad end of live segment, no basic block", MF, LR);
1481 // No more checks for live-out segments.
1482 if (S.end == LiveInts->getMBBEndIdx(EndMBB))
1485 // RegUnit intervals are allowed dead phis.
1486 if (!TargetRegisterInfo::isVirtualRegister(Reg) && VNI->isPHIDef() &&
1487 S.start == VNI->def && S.end == VNI->def.getDeadSlot())
1490 // The live segment is ending inside EndMBB
1491 const MachineInstr *MI =
1492 LiveInts->getInstructionFromIndex(S.end.getPrevSlot());
1494 report("Live segment doesn't end at a valid instruction", EndMBB, LR);
1499 // The block slot must refer to a basic block boundary.
1500 if (S.end.isBlock()) {
1501 report("Live segment ends at B slot of an instruction", EndMBB, LR);
1505 if (S.end.isDead()) {
1506 // Segment ends on the dead slot.
1507 // That means there must be a dead def.
1508 if (!SlotIndex::isSameInstr(S.start, S.end)) {
1509 report("Live segment ending at dead slot spans instructions", EndMBB, LR);
1514 // A live segment can only end at an early-clobber slot if it is being
1515 // redefined by an early-clobber def.
1516 if (S.end.isEarlyClobber()) {
1517 if (I+1 == LR.end() || (I+1)->start != S.end) {
1518 report("Live segment ending at early clobber slot must be "
1519 "redefined by an EC def in the same instruction", EndMBB, LR);
1524 // The following checks only apply to virtual registers. Physreg liveness
1525 // is too weird to check.
1526 if (TargetRegisterInfo::isVirtualRegister(Reg)) {
1527 // A live segment can end with either a redefinition, a kill flag on a
1528 // use, or a dead flag on a def.
1529 bool hasRead = false;
1530 for (ConstMIBundleOperands MOI(MI); MOI.isValid(); ++MOI) {
1531 if (!MOI->isReg() || MOI->getReg() != Reg)
1533 if (MOI->readsReg())
1536 if (!S.end.isDead()) {
1538 report("Instruction ending live segment doesn't read the register", MI);
1539 *OS << S << " in " << LR << '\n';
1544 // Now check all the basic blocks in this live segment.
1545 MachineFunction::const_iterator MFI = MBB;
1546 // Is this live segment the beginning of a non-PHIDef VN?
1547 if (S.start == VNI->def && !VNI->isPHIDef()) {
1548 // Not live-in to any blocks.
1555 assert(LiveInts->isLiveInToMBB(LR, MFI));
1556 // We don't know how to track physregs into a landing pad.
1557 if (!TargetRegisterInfo::isVirtualRegister(Reg) &&
1558 MFI->isLandingPad()) {
1559 if (&*MFI == EndMBB)
1565 // Is VNI a PHI-def in the current block?
1566 bool IsPHI = VNI->isPHIDef() &&
1567 VNI->def == LiveInts->getMBBStartIdx(MFI);
1569 // Check that VNI is live-out of all predecessors.
1570 for (MachineBasicBlock::const_pred_iterator PI = MFI->pred_begin(),
1571 PE = MFI->pred_end(); PI != PE; ++PI) {
1572 SlotIndex PEnd = LiveInts->getMBBEndIdx(*PI);
1573 const VNInfo *PVNI = LR.getVNInfoBefore(PEnd);
1575 // All predecessors must have a live-out value.
1577 report("Register not marked live out of predecessor", *PI, LR);
1578 *OS << "Valno #" << VNI->id << " live into BB#" << MFI->getNumber()
1579 << '@' << LiveInts->getMBBStartIdx(MFI) << ", not live before "
1584 // Only PHI-defs can take different predecessor values.
1585 if (!IsPHI && PVNI != VNI) {
1586 report("Different value live out of predecessor", *PI, LR);
1587 *OS << "Valno #" << PVNI->id << " live out of BB#"
1588 << (*PI)->getNumber() << '@' << PEnd
1589 << "\nValno #" << VNI->id << " live into BB#" << MFI->getNumber()
1590 << '@' << LiveInts->getMBBStartIdx(MFI) << '\n';
1593 if (&*MFI == EndMBB)
1599 void MachineVerifier::verifyLiveRange(const LiveRange &LR, unsigned Reg) {
1600 for (LiveRange::const_vni_iterator I = LR.vni_begin(), E = LR.vni_end();
1602 verifyLiveRangeValue(LR, *I, Reg);
1604 for (LiveRange::const_iterator I = LR.begin(), E = LR.end(); I != E; ++I)
1605 verifyLiveRangeSegment(LR, I, Reg);
1608 void MachineVerifier::verifyLiveInterval(const LiveInterval &LI) {
1609 verifyLiveRange(LI, LI.reg);
1611 // Check the LI only has one connected component.
1612 if (TargetRegisterInfo::isVirtualRegister(LI.reg)) {
1613 ConnectedVNInfoEqClasses ConEQ(*LiveInts);
1614 unsigned NumComp = ConEQ.Classify(&LI);
1616 report("Multiple connected components in live interval", MF, LI);
1617 for (unsigned comp = 0; comp != NumComp; ++comp) {
1618 *OS << comp << ": valnos";
1619 for (LiveInterval::const_vni_iterator I = LI.vni_begin(),
1620 E = LI.vni_end(); I!=E; ++I)
1621 if (comp == ConEQ.getEqClass(*I))
1622 *OS << ' ' << (*I)->id;
1630 // FrameSetup and FrameDestroy can have zero adjustment, so using a single
1631 // integer, we can't tell whether it is a FrameSetup or FrameDestroy if the
1633 // We use a bool plus an integer to capture the stack state.
1634 struct StackStateOfBB {
1635 StackStateOfBB() : EntryValue(0), ExitValue(0), EntryIsSetup(false),
1636 ExitIsSetup(false) { }
1637 StackStateOfBB(int EntryVal, int ExitVal, bool EntrySetup, bool ExitSetup) :
1638 EntryValue(EntryVal), ExitValue(ExitVal), EntryIsSetup(EntrySetup),
1639 ExitIsSetup(ExitSetup) { }
1640 // Can be negative, which means we are setting up a frame.
1648 /// Make sure on every path through the CFG, a FrameSetup <n> is always followed
1649 /// by a FrameDestroy <n>, stack adjustments are identical on all
1650 /// CFG edges to a merge point, and frame is destroyed at end of a return block.
1651 void MachineVerifier::verifyStackFrame() {
1652 int FrameSetupOpcode = TII->getCallFrameSetupOpcode();
1653 int FrameDestroyOpcode = TII->getCallFrameDestroyOpcode();
1655 SmallVector<StackStateOfBB, 8> SPState;
1656 SPState.resize(MF->getNumBlockIDs());
1657 SmallPtrSet<const MachineBasicBlock*, 8> Reachable;
1659 // Visit the MBBs in DFS order.
1660 for (df_ext_iterator<const MachineFunction*,
1661 SmallPtrSet<const MachineBasicBlock*, 8> >
1662 DFI = df_ext_begin(MF, Reachable), DFE = df_ext_end(MF, Reachable);
1663 DFI != DFE; ++DFI) {
1664 const MachineBasicBlock *MBB = *DFI;
1666 StackStateOfBB BBState;
1667 // Check the exit state of the DFS stack predecessor.
1668 if (DFI.getPathLength() >= 2) {
1669 const MachineBasicBlock *StackPred = DFI.getPath(DFI.getPathLength() - 2);
1670 assert(Reachable.count(StackPred) &&
1671 "DFS stack predecessor is already visited.\n");
1672 BBState.EntryValue = SPState[StackPred->getNumber()].ExitValue;
1673 BBState.EntryIsSetup = SPState[StackPred->getNumber()].ExitIsSetup;
1674 BBState.ExitValue = BBState.EntryValue;
1675 BBState.ExitIsSetup = BBState.EntryIsSetup;
1678 // Update stack state by checking contents of MBB.
1679 for (MachineBasicBlock::const_iterator I = MBB->begin(), E = MBB->end();
1681 if (I->getOpcode() == FrameSetupOpcode) {
1682 // The first operand of a FrameOpcode should be i32.
1683 int Size = I->getOperand(0).getImm();
1685 "Value should be non-negative in FrameSetup and FrameDestroy.\n");
1687 if (BBState.ExitIsSetup)
1688 report("FrameSetup is after another FrameSetup", I);
1689 BBState.ExitValue -= Size;
1690 BBState.ExitIsSetup = true;
1693 if (I->getOpcode() == FrameDestroyOpcode) {
1694 // The first operand of a FrameOpcode should be i32.
1695 int Size = I->getOperand(0).getImm();
1697 "Value should be non-negative in FrameSetup and FrameDestroy.\n");
1699 if (!BBState.ExitIsSetup)
1700 report("FrameDestroy is not after a FrameSetup", I);
1701 int AbsSPAdj = BBState.ExitValue < 0 ? -BBState.ExitValue :
1703 if (BBState.ExitIsSetup && AbsSPAdj != Size) {
1704 report("FrameDestroy <n> is after FrameSetup <m>", I);
1705 *OS << "FrameDestroy <" << Size << "> is after FrameSetup <"
1706 << AbsSPAdj << ">.\n";
1708 BBState.ExitValue += Size;
1709 BBState.ExitIsSetup = false;
1712 SPState[MBB->getNumber()] = BBState;
1714 // Make sure the exit state of any predecessor is consistent with the entry
1716 for (MachineBasicBlock::const_pred_iterator I = MBB->pred_begin(),
1717 E = MBB->pred_end(); I != E; ++I) {
1718 if (Reachable.count(*I) &&
1719 (SPState[(*I)->getNumber()].ExitValue != BBState.EntryValue ||
1720 SPState[(*I)->getNumber()].ExitIsSetup != BBState.EntryIsSetup)) {
1721 report("The exit stack state of a predecessor is inconsistent.", MBB);
1722 *OS << "Predecessor BB#" << (*I)->getNumber() << " has exit state ("
1723 << SPState[(*I)->getNumber()].ExitValue << ", "
1724 << SPState[(*I)->getNumber()].ExitIsSetup
1725 << "), while BB#" << MBB->getNumber() << " has entry state ("
1726 << BBState.EntryValue << ", " << BBState.EntryIsSetup << ").\n";
1730 // Make sure the entry state of any successor is consistent with the exit
1732 for (MachineBasicBlock::const_succ_iterator I = MBB->succ_begin(),
1733 E = MBB->succ_end(); I != E; ++I) {
1734 if (Reachable.count(*I) &&
1735 (SPState[(*I)->getNumber()].EntryValue != BBState.ExitValue ||
1736 SPState[(*I)->getNumber()].EntryIsSetup != BBState.ExitIsSetup)) {
1737 report("The entry stack state of a successor is inconsistent.", MBB);
1738 *OS << "Successor BB#" << (*I)->getNumber() << " has entry state ("
1739 << SPState[(*I)->getNumber()].EntryValue << ", "
1740 << SPState[(*I)->getNumber()].EntryIsSetup
1741 << "), while BB#" << MBB->getNumber() << " has exit state ("
1742 << BBState.ExitValue << ", " << BBState.ExitIsSetup << ").\n";
1746 // Make sure a basic block with return ends with zero stack adjustment.
1747 if (!MBB->empty() && MBB->back().isReturn()) {
1748 if (BBState.ExitIsSetup)
1749 report("A return block ends with a FrameSetup.", MBB);
1750 if (BBState.ExitValue)
1751 report("A return block ends with a nonzero stack adjustment.", MBB);