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/raw_ostream.h"
46 #include "llvm/Target/TargetInstrInfo.h"
47 #include "llvm/Target/TargetMachine.h"
48 #include "llvm/Target/TargetRegisterInfo.h"
52 struct MachineVerifier {
54 MachineVerifier(Pass *pass, const char *b) :
57 OutFileName(getenv("LLVM_VERIFY_MACHINEINSTRS"))
60 bool runOnMachineFunction(MachineFunction &MF);
64 const char *const OutFileName;
66 const MachineFunction *MF;
67 const TargetMachine *TM;
68 const TargetInstrInfo *TII;
69 const TargetRegisterInfo *TRI;
70 const MachineRegisterInfo *MRI;
74 typedef SmallVector<unsigned, 16> RegVector;
75 typedef SmallVector<const uint32_t*, 4> RegMaskVector;
76 typedef DenseSet<unsigned> RegSet;
77 typedef DenseMap<unsigned, const MachineInstr*> RegMap;
78 typedef SmallPtrSet<const MachineBasicBlock*, 8> BlockSet;
80 const MachineInstr *FirstTerminator;
81 BlockSet FunctionBlocks;
83 BitVector regsReserved;
85 RegVector regsDefined, regsDead, regsKilled;
86 RegMaskVector regMasks;
87 RegSet regsLiveInButUnused;
91 // Add Reg and any sub-registers to RV
92 void addRegWithSubRegs(RegVector &RV, unsigned Reg) {
94 if (TargetRegisterInfo::isPhysicalRegister(Reg))
95 for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs)
96 RV.push_back(*SubRegs);
100 // Is this MBB reachable from the MF entry point?
103 // Vregs that must be live in because they are used without being
104 // defined. Map value is the user.
107 // Regs killed in MBB. They may be defined again, and will then be in both
108 // regsKilled and regsLiveOut.
111 // Regs defined in MBB and live out. Note that vregs passing through may
112 // be live out without being mentioned here.
115 // Vregs that pass through MBB untouched. This set is disjoint from
116 // regsKilled and regsLiveOut.
119 // Vregs that must pass through MBB because they are needed by a successor
120 // block. This set is disjoint from regsLiveOut.
121 RegSet vregsRequired;
123 // Set versions of block's predecessor and successor lists.
124 BlockSet Preds, Succs;
126 BBInfo() : reachable(false) {}
128 // Add register to vregsPassed if it belongs there. Return true if
130 bool addPassed(unsigned Reg) {
131 if (!TargetRegisterInfo::isVirtualRegister(Reg))
133 if (regsKilled.count(Reg) || regsLiveOut.count(Reg))
135 return vregsPassed.insert(Reg).second;
138 // Same for a full set.
139 bool addPassed(const RegSet &RS) {
140 bool changed = false;
141 for (RegSet::const_iterator I = RS.begin(), E = RS.end(); I != E; ++I)
147 // Add register to vregsRequired if it belongs there. Return true if
149 bool addRequired(unsigned Reg) {
150 if (!TargetRegisterInfo::isVirtualRegister(Reg))
152 if (regsLiveOut.count(Reg))
154 return vregsRequired.insert(Reg).second;
157 // Same for a full set.
158 bool addRequired(const RegSet &RS) {
159 bool changed = false;
160 for (RegSet::const_iterator I = RS.begin(), E = RS.end(); I != E; ++I)
166 // Same for a full map.
167 bool addRequired(const RegMap &RM) {
168 bool changed = false;
169 for (RegMap::const_iterator I = RM.begin(), E = RM.end(); I != E; ++I)
170 if (addRequired(I->first))
175 // Live-out registers are either in regsLiveOut or vregsPassed.
176 bool isLiveOut(unsigned Reg) const {
177 return regsLiveOut.count(Reg) || vregsPassed.count(Reg);
181 // Extra register info per MBB.
182 DenseMap<const MachineBasicBlock*, BBInfo> MBBInfoMap;
184 bool isReserved(unsigned Reg) {
185 return Reg < regsReserved.size() && regsReserved.test(Reg);
188 bool isAllocatable(unsigned Reg) {
189 return Reg < TRI->getNumRegs() && MRI->isAllocatable(Reg);
192 // Analysis information if available
193 LiveVariables *LiveVars;
194 LiveIntervals *LiveInts;
195 LiveStacks *LiveStks;
196 SlotIndexes *Indexes;
198 void visitMachineFunctionBefore();
199 void visitMachineBasicBlockBefore(const MachineBasicBlock *MBB);
200 void visitMachineBundleBefore(const MachineInstr *MI);
201 void visitMachineInstrBefore(const MachineInstr *MI);
202 void visitMachineOperand(const MachineOperand *MO, unsigned MONum);
203 void visitMachineInstrAfter(const MachineInstr *MI);
204 void visitMachineBundleAfter(const MachineInstr *MI);
205 void visitMachineBasicBlockAfter(const MachineBasicBlock *MBB);
206 void visitMachineFunctionAfter();
208 void report(const char *msg, const MachineFunction *MF);
209 void report(const char *msg, const MachineBasicBlock *MBB);
210 void report(const char *msg, const MachineInstr *MI);
211 void report(const char *msg, const MachineOperand *MO, unsigned MONum);
212 void report(const char *msg, const MachineFunction *MF,
213 const LiveInterval &LI);
214 void report(const char *msg, const MachineBasicBlock *MBB,
215 const LiveInterval &LI);
216 void report(const char *msg, const MachineFunction *MF,
217 const LiveRange &LR);
218 void report(const char *msg, const MachineBasicBlock *MBB,
219 const LiveRange &LR);
221 void verifyInlineAsm(const MachineInstr *MI);
223 void checkLiveness(const MachineOperand *MO, unsigned MONum);
224 void markReachable(const MachineBasicBlock *MBB);
225 void calcRegsPassed();
226 void checkPHIOps(const MachineBasicBlock *MBB);
228 void calcRegsRequired();
229 void verifyLiveVariables();
230 void verifyLiveIntervals();
231 void verifyLiveInterval(const LiveInterval&);
232 void verifyLiveRangeValue(const LiveRange&, const VNInfo*, unsigned);
233 void verifyLiveRangeSegment(const LiveRange&,
234 const LiveRange::const_iterator I, unsigned);
235 void verifyLiveRange(const LiveRange&, unsigned);
237 void verifyStackFrame();
240 struct MachineVerifierPass : public MachineFunctionPass {
241 static char ID; // Pass ID, replacement for typeid
242 const char *const Banner;
244 MachineVerifierPass(const char *b = 0)
245 : MachineFunctionPass(ID), Banner(b) {
246 initializeMachineVerifierPassPass(*PassRegistry::getPassRegistry());
249 void getAnalysisUsage(AnalysisUsage &AU) const {
250 AU.setPreservesAll();
251 MachineFunctionPass::getAnalysisUsage(AU);
254 bool runOnMachineFunction(MachineFunction &MF) {
255 MF.verify(this, Banner);
262 char MachineVerifierPass::ID = 0;
263 INITIALIZE_PASS(MachineVerifierPass, "machineverifier",
264 "Verify generated machine code", false, false)
266 FunctionPass *llvm::createMachineVerifierPass(const char *Banner) {
267 return new MachineVerifierPass(Banner);
270 void MachineFunction::verify(Pass *p, const char *Banner) const {
271 MachineVerifier(p, Banner)
272 .runOnMachineFunction(const_cast<MachineFunction&>(*this));
275 bool MachineVerifier::runOnMachineFunction(MachineFunction &MF) {
276 raw_ostream *OutFile = 0;
278 std::string ErrorInfo;
279 OutFile = new raw_fd_ostream(OutFileName, ErrorInfo, sys::fs::F_Append);
280 if (!ErrorInfo.empty()) {
281 errs() << "Error opening '" << OutFileName << "': " << ErrorInfo << '\n';
293 TM = &MF.getTarget();
294 TII = TM->getInstrInfo();
295 TRI = TM->getRegisterInfo();
296 MRI = &MF.getRegInfo();
303 LiveInts = PASS->getAnalysisIfAvailable<LiveIntervals>();
304 // We don't want to verify LiveVariables if LiveIntervals is available.
306 LiveVars = PASS->getAnalysisIfAvailable<LiveVariables>();
307 LiveStks = PASS->getAnalysisIfAvailable<LiveStacks>();
308 Indexes = PASS->getAnalysisIfAvailable<SlotIndexes>();
311 visitMachineFunctionBefore();
312 for (MachineFunction::const_iterator MFI = MF.begin(), MFE = MF.end();
314 visitMachineBasicBlockBefore(MFI);
315 // Keep track of the current bundle header.
316 const MachineInstr *CurBundle = 0;
317 // Do we expect the next instruction to be part of the same bundle?
318 bool InBundle = false;
320 for (MachineBasicBlock::const_instr_iterator MBBI = MFI->instr_begin(),
321 MBBE = MFI->instr_end(); MBBI != MBBE; ++MBBI) {
322 if (MBBI->getParent() != MFI) {
323 report("Bad instruction parent pointer", MFI);
324 *OS << "Instruction: " << *MBBI;
328 // Check for consistent bundle flags.
329 if (InBundle && !MBBI->isBundledWithPred())
330 report("Missing BundledPred flag, "
331 "BundledSucc was set on predecessor", MBBI);
332 if (!InBundle && MBBI->isBundledWithPred())
333 report("BundledPred flag is set, "
334 "but BundledSucc not set on predecessor", MBBI);
336 // Is this a bundle header?
337 if (!MBBI->isInsideBundle()) {
339 visitMachineBundleAfter(CurBundle);
341 visitMachineBundleBefore(CurBundle);
342 } else if (!CurBundle)
343 report("No bundle header", MBBI);
344 visitMachineInstrBefore(MBBI);
345 for (unsigned I = 0, E = MBBI->getNumOperands(); I != E; ++I)
346 visitMachineOperand(&MBBI->getOperand(I), I);
347 visitMachineInstrAfter(MBBI);
349 // Was this the last bundled instruction?
350 InBundle = MBBI->isBundledWithSucc();
353 visitMachineBundleAfter(CurBundle);
355 report("BundledSucc flag set on last instruction in block", &MFI->back());
356 visitMachineBasicBlockAfter(MFI);
358 visitMachineFunctionAfter();
362 else if (foundErrors)
363 report_fatal_error("Found "+Twine(foundErrors)+" machine code errors.");
371 regsLiveInButUnused.clear();
374 return false; // no changes
377 void MachineVerifier::report(const char *msg, const MachineFunction *MF) {
380 if (!foundErrors++) {
382 *OS << "# " << Banner << '\n';
383 MF->print(*OS, Indexes);
385 *OS << "*** Bad machine code: " << msg << " ***\n"
386 << "- function: " << MF->getName() << "\n";
389 void MachineVerifier::report(const char *msg, const MachineBasicBlock *MBB) {
391 report(msg, MBB->getParent());
392 *OS << "- basic block: BB#" << MBB->getNumber()
393 << ' ' << MBB->getName()
394 << " (" << (const void*)MBB << ')';
396 *OS << " [" << Indexes->getMBBStartIdx(MBB)
397 << ';' << Indexes->getMBBEndIdx(MBB) << ')';
401 void MachineVerifier::report(const char *msg, const MachineInstr *MI) {
403 report(msg, MI->getParent());
404 *OS << "- instruction: ";
405 if (Indexes && Indexes->hasIndex(MI))
406 *OS << Indexes->getInstructionIndex(MI) << '\t';
410 void MachineVerifier::report(const char *msg,
411 const MachineOperand *MO, unsigned MONum) {
413 report(msg, MO->getParent());
414 *OS << "- operand " << MONum << ": ";
419 void MachineVerifier::report(const char *msg, const MachineFunction *MF,
420 const LiveInterval &LI) {
422 *OS << "- interval: ";
423 if (TargetRegisterInfo::isVirtualRegister(LI.reg))
424 *OS << PrintReg(LI.reg, TRI);
426 *OS << PrintRegUnit(LI.reg, TRI);
427 *OS << ' ' << LI << '\n';
430 void MachineVerifier::report(const char *msg, const MachineBasicBlock *MBB,
431 const LiveInterval &LI) {
433 *OS << "- interval: ";
434 if (TargetRegisterInfo::isVirtualRegister(LI.reg))
435 *OS << PrintReg(LI.reg, TRI);
437 *OS << PrintRegUnit(LI.reg, TRI);
438 *OS << ' ' << LI << '\n';
441 void MachineVerifier::report(const char *msg, const MachineBasicBlock *MBB,
442 const LiveRange &LR) {
444 *OS << "- liverange: " << LR << "\n";
447 void MachineVerifier::report(const char *msg, const MachineFunction *MF,
448 const LiveRange &LR) {
450 *OS << "- liverange: " << LR << "\n";
453 void MachineVerifier::markReachable(const MachineBasicBlock *MBB) {
454 BBInfo &MInfo = MBBInfoMap[MBB];
455 if (!MInfo.reachable) {
456 MInfo.reachable = true;
457 for (MachineBasicBlock::const_succ_iterator SuI = MBB->succ_begin(),
458 SuE = MBB->succ_end(); SuI != SuE; ++SuI)
463 void MachineVerifier::visitMachineFunctionBefore() {
464 lastIndex = SlotIndex();
465 regsReserved = MRI->getReservedRegs();
467 // A sub-register of a reserved register is also reserved
468 for (int Reg = regsReserved.find_first(); Reg>=0;
469 Reg = regsReserved.find_next(Reg)) {
470 for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs) {
471 // FIXME: This should probably be:
472 // assert(regsReserved.test(*SubRegs) && "Non-reserved sub-register");
473 regsReserved.set(*SubRegs);
477 markReachable(&MF->front());
479 // Build a set of the basic blocks in the function.
480 FunctionBlocks.clear();
481 for (MachineFunction::const_iterator
482 I = MF->begin(), E = MF->end(); I != E; ++I) {
483 FunctionBlocks.insert(I);
484 BBInfo &MInfo = MBBInfoMap[I];
486 MInfo.Preds.insert(I->pred_begin(), I->pred_end());
487 if (MInfo.Preds.size() != I->pred_size())
488 report("MBB has duplicate entries in its predecessor list.", I);
490 MInfo.Succs.insert(I->succ_begin(), I->succ_end());
491 if (MInfo.Succs.size() != I->succ_size())
492 report("MBB has duplicate entries in its successor list.", I);
495 // Check that the register use lists are sane.
496 MRI->verifyUseLists();
501 // Does iterator point to a and b as the first two elements?
502 static bool matchPair(MachineBasicBlock::const_succ_iterator i,
503 const MachineBasicBlock *a, const MachineBasicBlock *b) {
512 MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
516 // If this block has allocatable physical registers live-in, check that
517 // it is an entry block or landing pad.
518 for (MachineBasicBlock::livein_iterator LI = MBB->livein_begin(),
519 LE = MBB->livein_end();
522 if (isAllocatable(reg) && !MBB->isLandingPad() &&
523 MBB != MBB->getParent()->begin()) {
524 report("MBB has allocable live-in, but isn't entry or landing-pad.", MBB);
529 // Count the number of landing pad successors.
530 SmallPtrSet<MachineBasicBlock*, 4> LandingPadSuccs;
531 for (MachineBasicBlock::const_succ_iterator I = MBB->succ_begin(),
532 E = MBB->succ_end(); I != E; ++I) {
533 if ((*I)->isLandingPad())
534 LandingPadSuccs.insert(*I);
535 if (!FunctionBlocks.count(*I))
536 report("MBB has successor that isn't part of the function.", MBB);
537 if (!MBBInfoMap[*I].Preds.count(MBB)) {
538 report("Inconsistent CFG", MBB);
539 *OS << "MBB is not in the predecessor list of the successor BB#"
540 << (*I)->getNumber() << ".\n";
544 // Check the predecessor list.
545 for (MachineBasicBlock::const_pred_iterator I = MBB->pred_begin(),
546 E = MBB->pred_end(); I != E; ++I) {
547 if (!FunctionBlocks.count(*I))
548 report("MBB has predecessor that isn't part of the function.", MBB);
549 if (!MBBInfoMap[*I].Succs.count(MBB)) {
550 report("Inconsistent CFG", MBB);
551 *OS << "MBB is not in the successor list of the predecessor BB#"
552 << (*I)->getNumber() << ".\n";
556 const MCAsmInfo *AsmInfo = TM->getMCAsmInfo();
557 const BasicBlock *BB = MBB->getBasicBlock();
558 if (LandingPadSuccs.size() > 1 &&
560 AsmInfo->getExceptionHandlingType() == ExceptionHandling::SjLj &&
561 BB && isa<SwitchInst>(BB->getTerminator())))
562 report("MBB has more than one landing pad successor", MBB);
564 // Call AnalyzeBranch. If it succeeds, there several more conditions to check.
565 MachineBasicBlock *TBB = 0, *FBB = 0;
566 SmallVector<MachineOperand, 4> Cond;
567 if (!TII->AnalyzeBranch(*const_cast<MachineBasicBlock *>(MBB),
569 // Ok, AnalyzeBranch thinks it knows what's going on with this block. Let's
570 // check whether its answers match up with reality.
572 // Block falls through to its successor.
573 MachineFunction::const_iterator MBBI = MBB;
575 if (MBBI == MF->end()) {
576 // It's possible that the block legitimately ends with a noreturn
577 // call or an unreachable, in which case it won't actually fall
578 // out the bottom of the function.
579 } else if (MBB->succ_size() == LandingPadSuccs.size()) {
580 // It's possible that the block legitimately ends with a noreturn
581 // call or an unreachable, in which case it won't actuall fall
583 } else if (MBB->succ_size() != 1+LandingPadSuccs.size()) {
584 report("MBB exits via unconditional fall-through but doesn't have "
585 "exactly one CFG successor!", MBB);
586 } else if (!MBB->isSuccessor(MBBI)) {
587 report("MBB exits via unconditional fall-through but its successor "
588 "differs from its CFG successor!", MBB);
590 if (!MBB->empty() && getBundleStart(&MBB->back())->isBarrier() &&
591 !TII->isPredicated(getBundleStart(&MBB->back()))) {
592 report("MBB exits via unconditional fall-through but ends with a "
593 "barrier instruction!", MBB);
596 report("MBB exits via unconditional fall-through but has a condition!",
599 } else if (TBB && !FBB && Cond.empty()) {
600 // Block unconditionally branches somewhere.
601 if (MBB->succ_size() != 1+LandingPadSuccs.size()) {
602 report("MBB exits via unconditional branch but doesn't have "
603 "exactly one CFG successor!", MBB);
604 } else if (!MBB->isSuccessor(TBB)) {
605 report("MBB exits via unconditional branch but the CFG "
606 "successor doesn't match the actual successor!", MBB);
609 report("MBB exits via unconditional branch but doesn't contain "
610 "any instructions!", MBB);
611 } else if (!getBundleStart(&MBB->back())->isBarrier()) {
612 report("MBB exits via unconditional branch but doesn't end with a "
613 "barrier instruction!", MBB);
614 } else if (!getBundleStart(&MBB->back())->isTerminator()) {
615 report("MBB exits via unconditional branch but the branch isn't a "
616 "terminator instruction!", MBB);
618 } else if (TBB && !FBB && !Cond.empty()) {
619 // Block conditionally branches somewhere, otherwise falls through.
620 MachineFunction::const_iterator MBBI = MBB;
622 if (MBBI == MF->end()) {
623 report("MBB conditionally falls through out of function!", MBB);
624 } else if (MBB->succ_size() == 1) {
625 // A conditional branch with only one successor is weird, but allowed.
627 report("MBB exits via conditional branch/fall-through but only has "
628 "one CFG successor!", MBB);
629 else if (TBB != *MBB->succ_begin())
630 report("MBB exits via conditional branch/fall-through but the CFG "
631 "successor don't match the actual successor!", MBB);
632 } else if (MBB->succ_size() != 2) {
633 report("MBB exits via conditional branch/fall-through but doesn't have "
634 "exactly two CFG successors!", MBB);
635 } else if (!matchPair(MBB->succ_begin(), TBB, MBBI)) {
636 report("MBB exits via conditional branch/fall-through but the CFG "
637 "successors don't match the actual successors!", MBB);
640 report("MBB exits via conditional branch/fall-through but doesn't "
641 "contain any instructions!", MBB);
642 } else if (getBundleStart(&MBB->back())->isBarrier()) {
643 report("MBB exits via conditional branch/fall-through but ends with a "
644 "barrier instruction!", MBB);
645 } else if (!getBundleStart(&MBB->back())->isTerminator()) {
646 report("MBB exits via conditional branch/fall-through but the branch "
647 "isn't a terminator instruction!", MBB);
649 } else if (TBB && FBB) {
650 // Block conditionally branches somewhere, otherwise branches
652 if (MBB->succ_size() == 1) {
653 // A conditional branch with only one successor is weird, but allowed.
655 report("MBB exits via conditional branch/branch through but only has "
656 "one CFG successor!", MBB);
657 else if (TBB != *MBB->succ_begin())
658 report("MBB exits via conditional branch/branch through but the CFG "
659 "successor don't match the actual successor!", MBB);
660 } else if (MBB->succ_size() != 2) {
661 report("MBB exits via conditional branch/branch but doesn't have "
662 "exactly two CFG successors!", MBB);
663 } else if (!matchPair(MBB->succ_begin(), TBB, FBB)) {
664 report("MBB exits via conditional branch/branch but the CFG "
665 "successors don't match the actual successors!", MBB);
668 report("MBB exits via conditional branch/branch but doesn't "
669 "contain any instructions!", MBB);
670 } else if (!getBundleStart(&MBB->back())->isBarrier()) {
671 report("MBB exits via conditional branch/branch but doesn't end with a "
672 "barrier instruction!", MBB);
673 } else if (!getBundleStart(&MBB->back())->isTerminator()) {
674 report("MBB exits via conditional branch/branch but the branch "
675 "isn't a terminator instruction!", MBB);
678 report("MBB exits via conditinal branch/branch but there's no "
682 report("AnalyzeBranch returned invalid data!", MBB);
687 for (MachineBasicBlock::livein_iterator I = MBB->livein_begin(),
688 E = MBB->livein_end(); I != E; ++I) {
689 if (!TargetRegisterInfo::isPhysicalRegister(*I)) {
690 report("MBB live-in list contains non-physical register", MBB);
693 for (MCSubRegIterator SubRegs(*I, TRI, /*IncludeSelf=*/true);
694 SubRegs.isValid(); ++SubRegs)
695 regsLive.insert(*SubRegs);
697 regsLiveInButUnused = regsLive;
699 const MachineFrameInfo *MFI = MF->getFrameInfo();
700 assert(MFI && "Function has no frame info");
701 BitVector PR = MFI->getPristineRegs(MBB);
702 for (int I = PR.find_first(); I>0; I = PR.find_next(I)) {
703 for (MCSubRegIterator SubRegs(I, TRI, /*IncludeSelf=*/true);
704 SubRegs.isValid(); ++SubRegs)
705 regsLive.insert(*SubRegs);
712 lastIndex = Indexes->getMBBStartIdx(MBB);
715 // This function gets called for all bundle headers, including normal
716 // stand-alone unbundled instructions.
717 void MachineVerifier::visitMachineBundleBefore(const MachineInstr *MI) {
718 if (Indexes && Indexes->hasIndex(MI)) {
719 SlotIndex idx = Indexes->getInstructionIndex(MI);
720 if (!(idx > lastIndex)) {
721 report("Instruction index out of order", MI);
722 *OS << "Last instruction was at " << lastIndex << '\n';
727 // Ensure non-terminators don't follow terminators.
728 // Ignore predicated terminators formed by if conversion.
729 // FIXME: If conversion shouldn't need to violate this rule.
730 if (MI->isTerminator() && !TII->isPredicated(MI)) {
731 if (!FirstTerminator)
732 FirstTerminator = MI;
733 } else if (FirstTerminator) {
734 report("Non-terminator instruction after the first terminator", MI);
735 *OS << "First terminator was:\t" << *FirstTerminator;
739 // The operands on an INLINEASM instruction must follow a template.
740 // Verify that the flag operands make sense.
741 void MachineVerifier::verifyInlineAsm(const MachineInstr *MI) {
742 // The first two operands on INLINEASM are the asm string and global flags.
743 if (MI->getNumOperands() < 2) {
744 report("Too few operands on inline asm", MI);
747 if (!MI->getOperand(0).isSymbol())
748 report("Asm string must be an external symbol", MI);
749 if (!MI->getOperand(1).isImm())
750 report("Asm flags must be an immediate", MI);
751 // Allowed flags are Extra_HasSideEffects = 1, Extra_IsAlignStack = 2,
752 // Extra_AsmDialect = 4, Extra_MayLoad = 8, and Extra_MayStore = 16.
753 if (!isUInt<5>(MI->getOperand(1).getImm()))
754 report("Unknown asm flags", &MI->getOperand(1), 1);
756 assert(InlineAsm::MIOp_FirstOperand == 2 && "Asm format changed");
758 unsigned OpNo = InlineAsm::MIOp_FirstOperand;
760 for (unsigned e = MI->getNumOperands(); OpNo < e; OpNo += NumOps) {
761 const MachineOperand &MO = MI->getOperand(OpNo);
762 // There may be implicit ops after the fixed operands.
765 NumOps = 1 + InlineAsm::getNumOperandRegisters(MO.getImm());
768 if (OpNo > MI->getNumOperands())
769 report("Missing operands in last group", MI);
771 // An optional MDNode follows the groups.
772 if (OpNo < MI->getNumOperands() && MI->getOperand(OpNo).isMetadata())
775 // All trailing operands must be implicit registers.
776 for (unsigned e = MI->getNumOperands(); OpNo < e; ++OpNo) {
777 const MachineOperand &MO = MI->getOperand(OpNo);
778 if (!MO.isReg() || !MO.isImplicit())
779 report("Expected implicit register after groups", &MO, OpNo);
783 void MachineVerifier::visitMachineInstrBefore(const MachineInstr *MI) {
784 const MCInstrDesc &MCID = MI->getDesc();
785 if (MI->getNumOperands() < MCID.getNumOperands()) {
786 report("Too few operands", MI);
787 *OS << MCID.getNumOperands() << " operands expected, but "
788 << MI->getNumExplicitOperands() << " given.\n";
791 // Check the tied operands.
792 if (MI->isInlineAsm())
795 // Check the MachineMemOperands for basic consistency.
796 for (MachineInstr::mmo_iterator I = MI->memoperands_begin(),
797 E = MI->memoperands_end(); I != E; ++I) {
798 if ((*I)->isLoad() && !MI->mayLoad())
799 report("Missing mayLoad flag", MI);
800 if ((*I)->isStore() && !MI->mayStore())
801 report("Missing mayStore flag", MI);
804 // Debug values must not have a slot index.
805 // Other instructions must have one, unless they are inside a bundle.
807 bool mapped = !LiveInts->isNotInMIMap(MI);
808 if (MI->isDebugValue()) {
810 report("Debug instruction has a slot index", MI);
811 } else if (MI->isInsideBundle()) {
813 report("Instruction inside bundle has a slot index", MI);
816 report("Missing slot index", MI);
821 if (!TII->verifyInstruction(MI, ErrorInfo))
822 report(ErrorInfo.data(), MI);
826 MachineVerifier::visitMachineOperand(const MachineOperand *MO, unsigned MONum) {
827 const MachineInstr *MI = MO->getParent();
828 const MCInstrDesc &MCID = MI->getDesc();
830 // The first MCID.NumDefs operands must be explicit register defines
831 if (MONum < MCID.getNumDefs()) {
832 const MCOperandInfo &MCOI = MCID.OpInfo[MONum];
834 report("Explicit definition must be a register", MO, MONum);
835 else if (!MO->isDef() && !MCOI.isOptionalDef())
836 report("Explicit definition marked as use", MO, MONum);
837 else if (MO->isImplicit())
838 report("Explicit definition marked as implicit", MO, MONum);
839 } else if (MONum < MCID.getNumOperands()) {
840 const MCOperandInfo &MCOI = MCID.OpInfo[MONum];
841 // Don't check if it's the last operand in a variadic instruction. See,
842 // e.g., LDM_RET in the arm back end.
844 !(MI->isVariadic() && MONum == MCID.getNumOperands()-1)) {
845 if (MO->isDef() && !MCOI.isOptionalDef())
846 report("Explicit operand marked as def", MO, MONum);
847 if (MO->isImplicit())
848 report("Explicit operand marked as implicit", MO, MONum);
851 int TiedTo = MCID.getOperandConstraint(MONum, MCOI::TIED_TO);
854 report("Tied use must be a register", MO, MONum);
855 else if (!MO->isTied())
856 report("Operand should be tied", MO, MONum);
857 else if (unsigned(TiedTo) != MI->findTiedOperandIdx(MONum))
858 report("Tied def doesn't match MCInstrDesc", MO, MONum);
859 } else if (MO->isReg() && MO->isTied())
860 report("Explicit operand should not be tied", MO, MONum);
862 // ARM adds %reg0 operands to indicate predicates. We'll allow that.
863 if (MO->isReg() && !MO->isImplicit() && !MI->isVariadic() && MO->getReg())
864 report("Extra explicit operand on non-variadic instruction", MO, MONum);
867 switch (MO->getType()) {
868 case MachineOperand::MO_Register: {
869 const unsigned Reg = MO->getReg();
872 if (MRI->tracksLiveness() && !MI->isDebugValue())
873 checkLiveness(MO, MONum);
875 // Verify the consistency of tied operands.
877 unsigned OtherIdx = MI->findTiedOperandIdx(MONum);
878 const MachineOperand &OtherMO = MI->getOperand(OtherIdx);
879 if (!OtherMO.isReg())
880 report("Must be tied to a register", MO, MONum);
881 if (!OtherMO.isTied())
882 report("Missing tie flags on tied operand", MO, MONum);
883 if (MI->findTiedOperandIdx(OtherIdx) != MONum)
884 report("Inconsistent tie links", MO, MONum);
885 if (MONum < MCID.getNumDefs()) {
886 if (OtherIdx < MCID.getNumOperands()) {
887 if (-1 == MCID.getOperandConstraint(OtherIdx, MCOI::TIED_TO))
888 report("Explicit def tied to explicit use without tie constraint",
891 if (!OtherMO.isImplicit())
892 report("Explicit def should be tied to implicit use", MO, MONum);
897 // Verify two-address constraints after leaving SSA form.
899 if (!MRI->isSSA() && MO->isUse() &&
900 MI->isRegTiedToDefOperand(MONum, &DefIdx) &&
901 Reg != MI->getOperand(DefIdx).getReg())
902 report("Two-address instruction operands must be identical", MO, MONum);
904 // Check register classes.
905 if (MONum < MCID.getNumOperands() && !MO->isImplicit()) {
906 unsigned SubIdx = MO->getSubReg();
908 if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
910 report("Illegal subregister index for physical register", MO, MONum);
913 if (const TargetRegisterClass *DRC =
914 TII->getRegClass(MCID, MONum, TRI, *MF)) {
915 if (!DRC->contains(Reg)) {
916 report("Illegal physical register for instruction", MO, MONum);
917 *OS << TRI->getName(Reg) << " is not a "
918 << DRC->getName() << " register.\n";
923 const TargetRegisterClass *RC = MRI->getRegClass(Reg);
925 const TargetRegisterClass *SRC =
926 TRI->getSubClassWithSubReg(RC, SubIdx);
928 report("Invalid subregister index for virtual register", MO, MONum);
929 *OS << "Register class " << RC->getName()
930 << " does not support subreg index " << SubIdx << "\n";
934 report("Invalid register class for subregister index", MO, MONum);
935 *OS << "Register class " << RC->getName()
936 << " does not fully support subreg index " << SubIdx << "\n";
940 if (const TargetRegisterClass *DRC =
941 TII->getRegClass(MCID, MONum, TRI, *MF)) {
943 const TargetRegisterClass *SuperRC =
944 TRI->getLargestLegalSuperClass(RC);
946 report("No largest legal super class exists.", MO, MONum);
949 DRC = TRI->getMatchingSuperRegClass(SuperRC, DRC, SubIdx);
951 report("No matching super-reg register class.", MO, MONum);
955 if (!RC->hasSuperClassEq(DRC)) {
956 report("Illegal virtual register for instruction", MO, MONum);
957 *OS << "Expected a " << DRC->getName() << " register, but got a "
958 << RC->getName() << " register\n";
966 case MachineOperand::MO_RegisterMask:
967 regMasks.push_back(MO->getRegMask());
970 case MachineOperand::MO_MachineBasicBlock:
971 if (MI->isPHI() && !MO->getMBB()->isSuccessor(MI->getParent()))
972 report("PHI operand is not in the CFG", MO, MONum);
975 case MachineOperand::MO_FrameIndex:
976 if (LiveStks && LiveStks->hasInterval(MO->getIndex()) &&
977 LiveInts && !LiveInts->isNotInMIMap(MI)) {
978 LiveInterval &LI = LiveStks->getInterval(MO->getIndex());
979 SlotIndex Idx = LiveInts->getInstructionIndex(MI);
980 if (MI->mayLoad() && !LI.liveAt(Idx.getRegSlot(true))) {
981 report("Instruction loads from dead spill slot", MO, MONum);
982 *OS << "Live stack: " << LI << '\n';
984 if (MI->mayStore() && !LI.liveAt(Idx.getRegSlot())) {
985 report("Instruction stores to dead spill slot", MO, MONum);
986 *OS << "Live stack: " << LI << '\n';
996 void MachineVerifier::checkLiveness(const MachineOperand *MO, unsigned MONum) {
997 const MachineInstr *MI = MO->getParent();
998 const unsigned Reg = MO->getReg();
1000 // Both use and def operands can read a register.
1001 if (MO->readsReg()) {
1002 regsLiveInButUnused.erase(Reg);
1005 addRegWithSubRegs(regsKilled, Reg);
1007 // Check that LiveVars knows this kill.
1008 if (LiveVars && TargetRegisterInfo::isVirtualRegister(Reg) &&
1010 LiveVariables::VarInfo &VI = LiveVars->getVarInfo(Reg);
1011 if (std::find(VI.Kills.begin(), VI.Kills.end(), MI) == VI.Kills.end())
1012 report("Kill missing from LiveVariables", MO, MONum);
1015 // Check LiveInts liveness and kill.
1016 if (LiveInts && !LiveInts->isNotInMIMap(MI)) {
1017 SlotIndex UseIdx = LiveInts->getInstructionIndex(MI);
1018 // Check the cached regunit intervals.
1019 if (TargetRegisterInfo::isPhysicalRegister(Reg) && !isReserved(Reg)) {
1020 for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units) {
1021 if (const LiveInterval *LI = LiveInts->getCachedRegUnit(*Units)) {
1022 LiveQueryResult LRQ = LI->Query(UseIdx);
1023 if (!LRQ.valueIn()) {
1024 report("No live segment at use", MO, MONum);
1025 *OS << UseIdx << " is not live in " << PrintRegUnit(*Units, TRI)
1026 << ' ' << *LI << '\n';
1028 if (MO->isKill() && !LRQ.isKill()) {
1029 report("Live range continues after kill flag", MO, MONum);
1030 *OS << PrintRegUnit(*Units, TRI) << ' ' << *LI << '\n';
1036 if (TargetRegisterInfo::isVirtualRegister(Reg)) {
1037 if (LiveInts->hasInterval(Reg)) {
1038 // This is a virtual register interval.
1039 const LiveInterval &LI = LiveInts->getInterval(Reg);
1040 LiveQueryResult LRQ = LI.Query(UseIdx);
1041 if (!LRQ.valueIn()) {
1042 report("No live segment at use", MO, MONum);
1043 *OS << UseIdx << " is not live in " << LI << '\n';
1045 // Check for extra kill flags.
1046 // Note that we allow missing kill flags for now.
1047 if (MO->isKill() && !LRQ.isKill()) {
1048 report("Live range continues after kill flag", MO, MONum);
1049 *OS << "Live range: " << LI << '\n';
1052 report("Virtual register has no live interval", MO, MONum);
1057 // Use of a dead register.
1058 if (!regsLive.count(Reg)) {
1059 if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
1060 // Reserved registers may be used even when 'dead'.
1061 if (!isReserved(Reg))
1062 report("Using an undefined physical register", MO, MONum);
1063 } else if (MRI->def_empty(Reg)) {
1064 report("Reading virtual register without a def", MO, MONum);
1066 BBInfo &MInfo = MBBInfoMap[MI->getParent()];
1067 // We don't know which virtual registers are live in, so only complain
1068 // if vreg was killed in this MBB. Otherwise keep track of vregs that
1069 // must be live in. PHI instructions are handled separately.
1070 if (MInfo.regsKilled.count(Reg))
1071 report("Using a killed virtual register", MO, MONum);
1072 else if (!MI->isPHI())
1073 MInfo.vregsLiveIn.insert(std::make_pair(Reg, MI));
1079 // Register defined.
1080 // TODO: verify that earlyclobber ops are not used.
1082 addRegWithSubRegs(regsDead, Reg);
1084 addRegWithSubRegs(regsDefined, Reg);
1087 if (MRI->isSSA() && TargetRegisterInfo::isVirtualRegister(Reg) &&
1088 llvm::next(MRI->def_begin(Reg)) != MRI->def_end())
1089 report("Multiple virtual register defs in SSA form", MO, MONum);
1091 // Check LiveInts for a live segment, but only for virtual registers.
1092 if (LiveInts && TargetRegisterInfo::isVirtualRegister(Reg) &&
1093 !LiveInts->isNotInMIMap(MI)) {
1094 SlotIndex DefIdx = LiveInts->getInstructionIndex(MI);
1095 DefIdx = DefIdx.getRegSlot(MO->isEarlyClobber());
1096 if (LiveInts->hasInterval(Reg)) {
1097 const LiveInterval &LI = LiveInts->getInterval(Reg);
1098 if (const VNInfo *VNI = LI.getVNInfoAt(DefIdx)) {
1099 assert(VNI && "NULL valno is not allowed");
1100 if (VNI->def != DefIdx) {
1101 report("Inconsistent valno->def", MO, MONum);
1102 *OS << "Valno " << VNI->id << " is not defined at "
1103 << DefIdx << " in " << LI << '\n';
1106 report("No live segment at def", MO, MONum);
1107 *OS << DefIdx << " is not live in " << 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 LiveInterval *LI = LiveInts->getCachedRegUnit(i))
1356 verifyLiveInterval(*LI);
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 bool hasDeadDef = false;
1531 for (ConstMIBundleOperands MOI(MI); MOI.isValid(); ++MOI) {
1532 if (!MOI->isReg() || MOI->getReg() != Reg)
1534 if (MOI->readsReg())
1536 if (MOI->isDef() && MOI->isDead())
1540 if (S.end.isDead()) {
1542 report("Instruction doesn't have a dead def operand", MI);
1543 *OS << S << " in " << LR << '\n';
1547 report("Instruction ending live segment doesn't read the register", MI);
1548 *OS << S << " in " << LR << '\n';
1553 // Now check all the basic blocks in this live segment.
1554 MachineFunction::const_iterator MFI = MBB;
1555 // Is this live segment the beginning of a non-PHIDef VN?
1556 if (S.start == VNI->def && !VNI->isPHIDef()) {
1557 // Not live-in to any blocks.
1564 assert(LiveInts->isLiveInToMBB(LR, MFI));
1565 // We don't know how to track physregs into a landing pad.
1566 if (!TargetRegisterInfo::isVirtualRegister(Reg) &&
1567 MFI->isLandingPad()) {
1568 if (&*MFI == EndMBB)
1574 // Is VNI a PHI-def in the current block?
1575 bool IsPHI = VNI->isPHIDef() &&
1576 VNI->def == LiveInts->getMBBStartIdx(MFI);
1578 // Check that VNI is live-out of all predecessors.
1579 for (MachineBasicBlock::const_pred_iterator PI = MFI->pred_begin(),
1580 PE = MFI->pred_end(); PI != PE; ++PI) {
1581 SlotIndex PEnd = LiveInts->getMBBEndIdx(*PI);
1582 const VNInfo *PVNI = LR.getVNInfoBefore(PEnd);
1584 // All predecessors must have a live-out value.
1586 report("Register not marked live out of predecessor", *PI, LR);
1587 *OS << "Valno #" << VNI->id << " live into BB#" << MFI->getNumber()
1588 << '@' << LiveInts->getMBBStartIdx(MFI) << ", not live before "
1593 // Only PHI-defs can take different predecessor values.
1594 if (!IsPHI && PVNI != VNI) {
1595 report("Different value live out of predecessor", *PI, LR);
1596 *OS << "Valno #" << PVNI->id << " live out of BB#"
1597 << (*PI)->getNumber() << '@' << PEnd
1598 << "\nValno #" << VNI->id << " live into BB#" << MFI->getNumber()
1599 << '@' << LiveInts->getMBBStartIdx(MFI) << '\n';
1602 if (&*MFI == EndMBB)
1608 void MachineVerifier::verifyLiveRange(const LiveRange &LR, unsigned Reg) {
1609 for (LiveRange::const_vni_iterator I = LR.vni_begin(), E = LR.vni_end();
1611 verifyLiveRangeValue(LR, *I, Reg);
1613 for (LiveRange::const_iterator I = LR.begin(), E = LR.end(); I != E; ++I)
1614 verifyLiveRangeSegment(LR, I, Reg);
1617 void MachineVerifier::verifyLiveInterval(const LiveInterval &LI) {
1618 verifyLiveRange(LI, LI.reg);
1620 // Check the LI only has one connected component.
1621 if (TargetRegisterInfo::isVirtualRegister(LI.reg)) {
1622 ConnectedVNInfoEqClasses ConEQ(*LiveInts);
1623 unsigned NumComp = ConEQ.Classify(&LI);
1625 report("Multiple connected components in live interval", MF, LI);
1626 for (unsigned comp = 0; comp != NumComp; ++comp) {
1627 *OS << comp << ": valnos";
1628 for (LiveInterval::const_vni_iterator I = LI.vni_begin(),
1629 E = LI.vni_end(); I!=E; ++I)
1630 if (comp == ConEQ.getEqClass(*I))
1631 *OS << ' ' << (*I)->id;
1639 // FrameSetup and FrameDestroy can have zero adjustment, so using a single
1640 // integer, we can't tell whether it is a FrameSetup or FrameDestroy if the
1642 // We use a bool plus an integer to capture the stack state.
1643 struct StackStateOfBB {
1644 StackStateOfBB() : EntryValue(0), ExitValue(0), EntryIsSetup(false),
1645 ExitIsSetup(false) { }
1646 StackStateOfBB(int EntryVal, int ExitVal, bool EntrySetup, bool ExitSetup) :
1647 EntryValue(EntryVal), ExitValue(ExitVal), EntryIsSetup(EntrySetup),
1648 ExitIsSetup(ExitSetup) { }
1649 // Can be negative, which means we are setting up a frame.
1657 /// Make sure on every path through the CFG, a FrameSetup <n> is always followed
1658 /// by a FrameDestroy <n>, stack adjustments are identical on all
1659 /// CFG edges to a merge point, and frame is destroyed at end of a return block.
1660 void MachineVerifier::verifyStackFrame() {
1661 int FrameSetupOpcode = TII->getCallFrameSetupOpcode();
1662 int FrameDestroyOpcode = TII->getCallFrameDestroyOpcode();
1664 SmallVector<StackStateOfBB, 8> SPState;
1665 SPState.resize(MF->getNumBlockIDs());
1666 SmallPtrSet<const MachineBasicBlock*, 8> Reachable;
1668 // Visit the MBBs in DFS order.
1669 for (df_ext_iterator<const MachineFunction*,
1670 SmallPtrSet<const MachineBasicBlock*, 8> >
1671 DFI = df_ext_begin(MF, Reachable), DFE = df_ext_end(MF, Reachable);
1672 DFI != DFE; ++DFI) {
1673 const MachineBasicBlock *MBB = *DFI;
1675 StackStateOfBB BBState;
1676 // Check the exit state of the DFS stack predecessor.
1677 if (DFI.getPathLength() >= 2) {
1678 const MachineBasicBlock *StackPred = DFI.getPath(DFI.getPathLength() - 2);
1679 assert(Reachable.count(StackPred) &&
1680 "DFS stack predecessor is already visited.\n");
1681 BBState.EntryValue = SPState[StackPred->getNumber()].ExitValue;
1682 BBState.EntryIsSetup = SPState[StackPred->getNumber()].ExitIsSetup;
1683 BBState.ExitValue = BBState.EntryValue;
1684 BBState.ExitIsSetup = BBState.EntryIsSetup;
1687 // Update stack state by checking contents of MBB.
1688 for (MachineBasicBlock::const_iterator I = MBB->begin(), E = MBB->end();
1690 if (I->getOpcode() == FrameSetupOpcode) {
1691 // The first operand of a FrameOpcode should be i32.
1692 int Size = I->getOperand(0).getImm();
1694 "Value should be non-negative in FrameSetup and FrameDestroy.\n");
1696 if (BBState.ExitIsSetup)
1697 report("FrameSetup is after another FrameSetup", I);
1698 BBState.ExitValue -= Size;
1699 BBState.ExitIsSetup = true;
1702 if (I->getOpcode() == FrameDestroyOpcode) {
1703 // The first operand of a FrameOpcode should be i32.
1704 int Size = I->getOperand(0).getImm();
1706 "Value should be non-negative in FrameSetup and FrameDestroy.\n");
1708 if (!BBState.ExitIsSetup)
1709 report("FrameDestroy is not after a FrameSetup", I);
1710 int AbsSPAdj = BBState.ExitValue < 0 ? -BBState.ExitValue :
1712 if (BBState.ExitIsSetup && AbsSPAdj != Size) {
1713 report("FrameDestroy <n> is after FrameSetup <m>", I);
1714 *OS << "FrameDestroy <" << Size << "> is after FrameSetup <"
1715 << AbsSPAdj << ">.\n";
1717 BBState.ExitValue += Size;
1718 BBState.ExitIsSetup = false;
1721 SPState[MBB->getNumber()] = BBState;
1723 // Make sure the exit state of any predecessor is consistent with the entry
1725 for (MachineBasicBlock::const_pred_iterator I = MBB->pred_begin(),
1726 E = MBB->pred_end(); I != E; ++I) {
1727 if (Reachable.count(*I) &&
1728 (SPState[(*I)->getNumber()].ExitValue != BBState.EntryValue ||
1729 SPState[(*I)->getNumber()].ExitIsSetup != BBState.EntryIsSetup)) {
1730 report("The exit stack state of a predecessor is inconsistent.", MBB);
1731 *OS << "Predecessor BB#" << (*I)->getNumber() << " has exit state ("
1732 << SPState[(*I)->getNumber()].ExitValue << ", "
1733 << SPState[(*I)->getNumber()].ExitIsSetup
1734 << "), while BB#" << MBB->getNumber() << " has entry state ("
1735 << BBState.EntryValue << ", " << BBState.EntryIsSetup << ").\n";
1739 // Make sure the entry state of any successor is consistent with the exit
1741 for (MachineBasicBlock::const_succ_iterator I = MBB->succ_begin(),
1742 E = MBB->succ_end(); I != E; ++I) {
1743 if (Reachable.count(*I) &&
1744 (SPState[(*I)->getNumber()].EntryValue != BBState.ExitValue ||
1745 SPState[(*I)->getNumber()].EntryIsSetup != BBState.ExitIsSetup)) {
1746 report("The entry stack state of a successor is inconsistent.", MBB);
1747 *OS << "Successor BB#" << (*I)->getNumber() << " has entry state ("
1748 << SPState[(*I)->getNumber()].EntryValue << ", "
1749 << SPState[(*I)->getNumber()].EntryIsSetup
1750 << "), while BB#" << MBB->getNumber() << " has exit state ("
1751 << BBState.ExitValue << ", " << BBState.ExitIsSetup << ").\n";
1755 // Make sure a basic block with return ends with zero stack adjustment.
1756 if (!MBB->empty() && MBB->back().isReturn()) {
1757 if (BBState.ExitIsSetup)
1758 report("A return block ends with a FrameSetup.", MBB);
1759 if (BBState.ExitValue)
1760 report("A return block ends with a nonzero stack adjustment.", MBB);