1 //===-- MachineVerifier.cpp - Machine Code Verifier -------------*- C++ -*-===//
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/Function.h"
27 #include "llvm/CodeGen/LiveVariables.h"
28 #include "llvm/CodeGen/MachineFunctionPass.h"
29 #include "llvm/CodeGen/MachineFrameInfo.h"
30 #include "llvm/CodeGen/MachineMemOperand.h"
31 #include "llvm/CodeGen/MachineRegisterInfo.h"
32 #include "llvm/CodeGen/Passes.h"
33 #include "llvm/Target/TargetMachine.h"
34 #include "llvm/Target/TargetRegisterInfo.h"
35 #include "llvm/Target/TargetInstrInfo.h"
36 #include "llvm/ADT/DenseSet.h"
37 #include "llvm/ADT/SetOperations.h"
38 #include "llvm/ADT/SmallVector.h"
39 #include "llvm/Support/Compiler.h"
40 #include "llvm/Support/Debug.h"
41 #include "llvm/Support/ErrorHandling.h"
42 #include "llvm/Support/raw_ostream.h"
46 struct MachineVerifier : public MachineFunctionPass {
47 static char ID; // Pass ID, replacement for typeid
49 MachineVerifier(bool allowDoubleDefs = false) :
50 MachineFunctionPass(&ID),
51 allowVirtDoubleDefs(allowDoubleDefs),
52 allowPhysDoubleDefs(allowDoubleDefs),
53 OutFileName(getenv("LLVM_VERIFY_MACHINEINSTRS"))
56 void getAnalysisUsage(AnalysisUsage &AU) const {
58 MachineFunctionPass::getAnalysisUsage(AU);
61 bool runOnMachineFunction(MachineFunction &MF);
63 const bool allowVirtDoubleDefs;
64 const bool allowPhysDoubleDefs;
66 const char *const OutFileName;
68 const MachineFunction *MF;
69 const TargetMachine *TM;
70 const TargetRegisterInfo *TRI;
71 const MachineRegisterInfo *MRI;
75 typedef SmallVector<unsigned, 16> RegVector;
76 typedef DenseSet<unsigned> RegSet;
77 typedef DenseMap<unsigned, const MachineInstr*> RegMap;
79 BitVector regsReserved;
81 RegVector regsDefined, regsDead, regsKilled;
82 RegSet regsLiveInButUnused;
84 // Add Reg and any sub-registers to RV
85 void addRegWithSubRegs(RegVector &RV, unsigned Reg) {
87 if (TargetRegisterInfo::isPhysicalRegister(Reg))
88 for (const unsigned *R = TRI->getSubRegisters(Reg); *R; R++)
93 // Is this MBB reachable from the MF entry point?
96 // Vregs that must be live in because they are used without being
97 // defined. Map value is the user.
100 // Vregs that must be dead in because they are defined without being
101 // killed first. Map value is the defining instruction.
104 // Regs killed in MBB. They may be defined again, and will then be in both
105 // regsKilled and regsLiveOut.
108 // Regs defined in MBB and live out. Note that vregs passing through may
109 // be live out without being mentioned here.
112 // Vregs that pass through MBB untouched. This set is disjoint from
113 // regsKilled and regsLiveOut.
116 BBInfo() : reachable(false) {}
118 // Add register to vregsPassed if it belongs there. Return true if
120 bool addPassed(unsigned Reg) {
121 if (!TargetRegisterInfo::isVirtualRegister(Reg))
123 if (regsKilled.count(Reg) || regsLiveOut.count(Reg))
125 return vregsPassed.insert(Reg).second;
128 // Same for a full set.
129 bool addPassed(const RegSet &RS) {
130 bool changed = false;
131 for (RegSet::const_iterator I = RS.begin(), E = RS.end(); I != E; ++I)
137 // Live-out registers are either in regsLiveOut or vregsPassed.
138 bool isLiveOut(unsigned Reg) const {
139 return regsLiveOut.count(Reg) || vregsPassed.count(Reg);
143 // Extra register info per MBB.
144 DenseMap<const MachineBasicBlock*, BBInfo> MBBInfoMap;
146 bool isReserved(unsigned Reg) {
147 return Reg < regsReserved.size() && regsReserved.test(Reg);
150 void visitMachineFunctionBefore();
151 void visitMachineBasicBlockBefore(const MachineBasicBlock *MBB);
152 void visitMachineInstrBefore(const MachineInstr *MI);
153 void visitMachineOperand(const MachineOperand *MO, unsigned MONum);
154 void visitMachineInstrAfter(const MachineInstr *MI);
155 void visitMachineBasicBlockAfter(const MachineBasicBlock *MBB);
156 void visitMachineFunctionAfter();
158 void report(const char *msg, const MachineFunction *MF);
159 void report(const char *msg, const MachineBasicBlock *MBB);
160 void report(const char *msg, const MachineInstr *MI);
161 void report(const char *msg, const MachineOperand *MO, unsigned MONum);
163 void markReachable(const MachineBasicBlock *MBB);
164 void calcMaxRegsPassed();
165 void calcMinRegsPassed();
166 void checkPHIOps(const MachineBasicBlock *MBB);
170 char MachineVerifier::ID = 0;
171 static RegisterPass<MachineVerifier>
172 MachineVer("machineverifier", "Verify generated machine code");
173 static const PassInfo *const MachineVerifyID = &MachineVer;
175 FunctionPass *llvm::createMachineVerifierPass(bool allowPhysDoubleDefs) {
176 return new MachineVerifier(allowPhysDoubleDefs);
179 bool MachineVerifier::runOnMachineFunction(MachineFunction &MF) {
180 raw_ostream *OutFile = 0;
182 std::string ErrorInfo;
183 OutFile = new raw_fd_ostream(OutFileName, ErrorInfo,
184 raw_fd_ostream::F_Append);
185 if (!ErrorInfo.empty()) {
186 errs() << "Error opening '" << OutFileName << "': " << ErrorInfo << '\n';
198 TM = &MF.getTarget();
199 TRI = TM->getRegisterInfo();
200 MRI = &MF.getRegInfo();
202 visitMachineFunctionBefore();
203 for (MachineFunction::const_iterator MFI = MF.begin(), MFE = MF.end();
205 visitMachineBasicBlockBefore(MFI);
206 for (MachineBasicBlock::const_iterator MBBI = MFI->begin(),
207 MBBE = MFI->end(); MBBI != MBBE; ++MBBI) {
208 visitMachineInstrBefore(MBBI);
209 for (unsigned I = 0, E = MBBI->getNumOperands(); I != E; ++I)
210 visitMachineOperand(&MBBI->getOperand(I), I);
211 visitMachineInstrAfter(MBBI);
213 visitMachineBasicBlockAfter(MFI);
215 visitMachineFunctionAfter();
219 else if (foundErrors)
220 llvm_report_error("Found "+Twine(foundErrors)+" machine code errors.");
227 regsLiveInButUnused.clear();
230 return false; // no changes
233 void MachineVerifier::report(const char *msg, const MachineFunction *MF) {
238 *OS << "*** Bad machine code: " << msg << " ***\n"
239 << "- function: " << MF->getFunction()->getNameStr() << "\n";
242 void MachineVerifier::report(const char *msg, const MachineBasicBlock *MBB) {
244 report(msg, MBB->getParent());
245 *OS << "- basic block: " << MBB->getBasicBlock()->getNameStr()
247 << " (#" << MBB->getNumber() << ")\n";
250 void MachineVerifier::report(const char *msg, const MachineInstr *MI) {
252 report(msg, MI->getParent());
253 *OS << "- instruction: ";
257 void MachineVerifier::report(const char *msg,
258 const MachineOperand *MO, unsigned MONum) {
260 report(msg, MO->getParent());
261 *OS << "- operand " << MONum << ": ";
266 void MachineVerifier::markReachable(const MachineBasicBlock *MBB) {
267 BBInfo &MInfo = MBBInfoMap[MBB];
268 if (!MInfo.reachable) {
269 MInfo.reachable = true;
270 for (MachineBasicBlock::const_succ_iterator SuI = MBB->succ_begin(),
271 SuE = MBB->succ_end(); SuI != SuE; ++SuI)
276 void MachineVerifier::visitMachineFunctionBefore() {
277 regsReserved = TRI->getReservedRegs(*MF);
279 // A sub-register of a reserved register is also reserved
280 for (int Reg = regsReserved.find_first(); Reg>=0;
281 Reg = regsReserved.find_next(Reg)) {
282 for (const unsigned *Sub = TRI->getSubRegisters(Reg); *Sub; ++Sub) {
283 // FIXME: This should probably be:
284 // assert(regsReserved.test(*Sub) && "Non-reserved sub-register");
285 regsReserved.set(*Sub);
288 markReachable(&MF->front());
291 void MachineVerifier::visitMachineBasicBlockBefore(const MachineBasicBlock *MBB) {
292 const TargetInstrInfo *TII = MF->getTarget().getInstrInfo();
294 // Start with minimal CFG sanity checks.
295 MachineFunction::const_iterator MBBI = MBB;
297 if (MBBI != MF->end()) {
298 // Block is not last in function.
299 if (!MBB->isSuccessor(MBBI)) {
300 // Block does not fall through.
302 report("MBB doesn't fall through but is empty!", MBB);
305 if (TII->BlockHasNoFallThrough(*MBB)) {
307 report("TargetInstrInfo says the block has no fall through, but the "
308 "block is empty!", MBB);
309 } else if (!MBB->back().getDesc().isBarrier()) {
310 report("TargetInstrInfo says the block has no fall through, but the "
311 "block does not end in a barrier!", MBB);
315 // Block is last in function.
317 report("MBB is last in function but is empty!", MBB);
321 // Call AnalyzeBranch. If it succeeds, there several more conditions to check.
322 MachineBasicBlock *TBB = 0, *FBB = 0;
323 SmallVector<MachineOperand, 4> Cond;
324 if (!TII->AnalyzeBranch(*const_cast<MachineBasicBlock *>(MBB),
326 // Ok, AnalyzeBranch thinks it knows what's going on with this block. Let's
327 // check whether its answers match up with reality.
329 // Block falls through to its successor.
330 MachineFunction::const_iterator MBBI = MBB;
332 if (MBBI == MF->end()) {
333 // It's possible that the block legitimately ends with a noreturn
334 // call or an unreachable, in which case it won't actually fall
335 // out the bottom of the function.
336 } else if (MBB->succ_empty()) {
337 // It's possible that the block legitimately ends with a noreturn
338 // call or an unreachable, in which case it won't actuall fall
340 } else if (MBB->succ_size() != 1) {
341 report("MBB exits via unconditional fall-through but doesn't have "
342 "exactly one CFG successor!", MBB);
343 } else if (MBB->succ_begin()[0] != MBBI) {
344 report("MBB exits via unconditional fall-through but its successor "
345 "differs from its CFG successor!", MBB);
347 if (!MBB->empty() && MBB->back().getDesc().isBarrier()) {
348 report("MBB exits via unconditional fall-through but ends with a "
349 "barrier instruction!", MBB);
352 report("MBB exits via unconditional fall-through but has a condition!",
355 } else if (TBB && !FBB && Cond.empty()) {
356 // Block unconditionally branches somewhere.
357 if (MBB->succ_size() != 1) {
358 report("MBB exits via unconditional branch but doesn't have "
359 "exactly one CFG successor!", MBB);
360 } else if (MBB->succ_begin()[0] != TBB) {
361 report("MBB exits via unconditional branch but the CFG "
362 "successor doesn't match the actual successor!", MBB);
365 report("MBB exits via unconditional branch but doesn't contain "
366 "any instructions!", MBB);
367 } else if (!MBB->back().getDesc().isBarrier()) {
368 report("MBB exits via unconditional branch but doesn't end with a "
369 "barrier instruction!", MBB);
370 } else if (!MBB->back().getDesc().isTerminator()) {
371 report("MBB exits via unconditional branch but the branch isn't a "
372 "terminator instruction!", MBB);
374 } else if (TBB && !FBB && !Cond.empty()) {
375 // Block conditionally branches somewhere, otherwise falls through.
376 MachineFunction::const_iterator MBBI = MBB;
378 if (MBBI == MF->end()) {
379 report("MBB conditionally falls through out of function!", MBB);
380 } if (MBB->succ_size() != 2) {
381 report("MBB exits via conditional branch/fall-through but doesn't have "
382 "exactly two CFG successors!", MBB);
383 } else if ((MBB->succ_begin()[0] == TBB && MBB->succ_end()[1] == MBBI) ||
384 (MBB->succ_begin()[1] == TBB && MBB->succ_end()[0] == MBBI)) {
385 report("MBB exits via conditional branch/fall-through but the CFG "
386 "successors don't match the actual successors!", MBB);
389 report("MBB exits via conditional branch/fall-through but doesn't "
390 "contain any instructions!", MBB);
391 } else if (MBB->back().getDesc().isBarrier()) {
392 report("MBB exits via conditional branch/fall-through but ends with a "
393 "barrier instruction!", MBB);
394 } else if (!MBB->back().getDesc().isTerminator()) {
395 report("MBB exits via conditional branch/fall-through but the branch "
396 "isn't a terminator instruction!", MBB);
398 } else if (TBB && FBB) {
399 // Block conditionally branches somewhere, otherwise branches
401 if (MBB->succ_size() != 2) {
402 report("MBB exits via conditional branch/branch but doesn't have "
403 "exactly two CFG successors!", MBB);
404 } else if ((MBB->succ_begin()[0] == TBB && MBB->succ_end()[1] == FBB) ||
405 (MBB->succ_begin()[1] == TBB && MBB->succ_end()[0] == FBB)) {
406 report("MBB exits via conditional branch/branch but the CFG "
407 "successors don't match the actual successors!", MBB);
410 report("MBB exits via conditional branch/branch but doesn't "
411 "contain any instructions!", MBB);
412 } else if (!MBB->back().getDesc().isBarrier()) {
413 report("MBB exits via conditional branch/branch but doesn't end with a "
414 "barrier instruction!", MBB);
415 } else if (!MBB->back().getDesc().isTerminator()) {
416 report("MBB exits via conditional branch/branch but the branch "
417 "isn't a terminator instruction!", MBB);
420 report("MBB exits via conditinal branch/branch but there's no "
424 report("AnalyzeBranch returned invalid data!", MBB);
429 for (MachineBasicBlock::const_livein_iterator I = MBB->livein_begin(),
430 E = MBB->livein_end(); I != E; ++I) {
431 if (!TargetRegisterInfo::isPhysicalRegister(*I)) {
432 report("MBB live-in list contains non-physical register", MBB);
436 for (const unsigned *R = TRI->getSubRegisters(*I); *R; R++)
439 regsLiveInButUnused = regsLive;
441 const MachineFrameInfo *MFI = MF->getFrameInfo();
442 assert(MFI && "Function has no frame info");
443 BitVector PR = MFI->getPristineRegs(MBB);
444 for (int I = PR.find_first(); I>0; I = PR.find_next(I)) {
446 for (const unsigned *R = TRI->getSubRegisters(I); *R; R++)
454 void MachineVerifier::visitMachineInstrBefore(const MachineInstr *MI) {
455 const TargetInstrDesc &TI = MI->getDesc();
456 if (MI->getNumOperands() < TI.getNumOperands()) {
457 report("Too few operands", MI);
458 *OS << TI.getNumOperands() << " operands expected, but "
459 << MI->getNumExplicitOperands() << " given.\n";
462 // Check the MachineMemOperands for basic consistency.
463 for (MachineInstr::mmo_iterator I = MI->memoperands_begin(),
464 E = MI->memoperands_end(); I != E; ++I) {
465 if ((*I)->isLoad() && !TI.mayLoad())
466 report("Missing mayLoad flag", MI);
467 if ((*I)->isStore() && !TI.mayStore())
468 report("Missing mayStore flag", MI);
473 MachineVerifier::visitMachineOperand(const MachineOperand *MO, unsigned MONum) {
474 const MachineInstr *MI = MO->getParent();
475 const TargetInstrDesc &TI = MI->getDesc();
477 // The first TI.NumDefs operands must be explicit register defines
478 if (MONum < TI.getNumDefs()) {
480 report("Explicit definition must be a register", MO, MONum);
481 else if (!MO->isDef())
482 report("Explicit definition marked as use", MO, MONum);
483 else if (MO->isImplicit())
484 report("Explicit definition marked as implicit", MO, MONum);
485 } else if (MONum < TI.getNumOperands()) {
488 report("Explicit operand marked as def", MO, MONum);
489 if (MO->isImplicit())
490 report("Explicit operand marked as implicit", MO, MONum);
493 if (MO->isReg() && !MO->isImplicit() && !TI.isVariadic())
494 report("Extra explicit operand on non-variadic instruction", MO, MONum);
497 switch (MO->getType()) {
498 case MachineOperand::MO_Register: {
499 const unsigned Reg = MO->getReg();
503 // Check Live Variables.
505 // An <undef> doesn't refer to any register, so just skip it.
506 } else if (MO->isUse()) {
507 regsLiveInButUnused.erase(Reg);
510 addRegWithSubRegs(regsKilled, Reg);
511 // Tied operands on two-address instuctions MUST NOT have a <kill> flag.
512 if (MI->isRegTiedToDefOperand(MONum))
513 report("Illegal kill flag on two-address instruction operand",
516 // TwoAddress instr modifying a reg is treated as kill+def.
518 if (MI->isRegTiedToDefOperand(MONum, &defIdx) &&
519 MI->getOperand(defIdx).getReg() == Reg)
520 addRegWithSubRegs(regsKilled, Reg);
522 // Use of a dead register.
523 if (!regsLive.count(Reg)) {
524 if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
525 // Reserved registers may be used even when 'dead'.
526 if (!isReserved(Reg))
527 report("Using an undefined physical register", MO, MONum);
529 BBInfo &MInfo = MBBInfoMap[MI->getParent()];
530 // We don't know which virtual registers are live in, so only complain
531 // if vreg was killed in this MBB. Otherwise keep track of vregs that
532 // must be live in. PHI instructions are handled separately.
533 if (MInfo.regsKilled.count(Reg))
534 report("Using a killed virtual register", MO, MONum);
535 else if (MI->getOpcode() != TargetInstrInfo::PHI)
536 MInfo.vregsLiveIn.insert(std::make_pair(Reg, MI));
542 // TODO: verify that earlyclobber ops are not used.
544 addRegWithSubRegs(regsDead, Reg);
546 addRegWithSubRegs(regsDefined, Reg);
549 // Check register classes.
550 if (MONum < TI.getNumOperands() && !MO->isImplicit()) {
551 const TargetOperandInfo &TOI = TI.OpInfo[MONum];
552 unsigned SubIdx = MO->getSubReg();
554 if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
557 unsigned s = TRI->getSubReg(Reg, SubIdx);
559 report("Invalid subregister index for physical register",
565 if (const TargetRegisterClass *DRC = TOI.getRegClass(TRI)) {
566 if (!DRC->contains(sr)) {
567 report("Illegal physical register for instruction", MO, MONum);
568 *OS << TRI->getName(sr) << " is not a "
569 << DRC->getName() << " register.\n";
574 const TargetRegisterClass *RC = MRI->getRegClass(Reg);
576 if (RC->subregclasses_begin()+SubIdx >= RC->subregclasses_end()) {
577 report("Invalid subregister index for virtual register", MO, MONum);
580 RC = *(RC->subregclasses_begin()+SubIdx);
582 if (const TargetRegisterClass *DRC = TOI.getRegClass(TRI)) {
583 if (RC != DRC && !RC->hasSuperClass(DRC)) {
584 report("Illegal virtual register for instruction", MO, MONum);
585 *OS << "Expected a " << DRC->getName() << " register, but got a "
586 << RC->getName() << " register\n";
594 case MachineOperand::MO_MachineBasicBlock:
595 if (MI->getOpcode() == TargetInstrInfo::PHI) {
596 if (!MO->getMBB()->isSuccessor(MI->getParent()))
597 report("PHI operand is not in the CFG", MO, MONum);
606 void MachineVerifier::visitMachineInstrAfter(const MachineInstr *MI) {
607 BBInfo &MInfo = MBBInfoMap[MI->getParent()];
608 set_union(MInfo.regsKilled, regsKilled);
609 set_subtract(regsLive, regsKilled);
612 // Verify that both <def> and <def,dead> operands refer to dead registers.
613 RegVector defs(regsDefined);
614 defs.append(regsDead.begin(), regsDead.end());
616 for (RegVector::const_iterator I = defs.begin(), E = defs.end();
618 if (regsLive.count(*I)) {
619 if (TargetRegisterInfo::isPhysicalRegister(*I)) {
620 if (!allowPhysDoubleDefs && !isReserved(*I) &&
621 !regsLiveInButUnused.count(*I)) {
622 report("Redefining a live physical register", MI);
623 *OS << "Register " << TRI->getName(*I)
624 << " was defined but already live.\n";
627 if (!allowVirtDoubleDefs) {
628 report("Redefining a live virtual register", MI);
629 *OS << "Virtual register %reg" << *I
630 << " was defined but already live.\n";
633 } else if (TargetRegisterInfo::isVirtualRegister(*I) &&
634 !MInfo.regsKilled.count(*I)) {
635 // Virtual register defined without being killed first must be dead on
637 MInfo.vregsDeadIn.insert(std::make_pair(*I, MI));
641 set_subtract(regsLive, regsDead); regsDead.clear();
642 set_union(regsLive, regsDefined); regsDefined.clear();
646 MachineVerifier::visitMachineBasicBlockAfter(const MachineBasicBlock *MBB) {
647 MBBInfoMap[MBB].regsLiveOut = regsLive;
651 // Calculate the largest possible vregsPassed sets. These are the registers that
652 // can pass through an MBB live, but may not be live every time. It is assumed
653 // that all vregsPassed sets are empty before the call.
654 void MachineVerifier::calcMaxRegsPassed() {
655 // First push live-out regs to successors' vregsPassed. Remember the MBBs that
656 // have any vregsPassed.
657 DenseSet<const MachineBasicBlock*> todo;
658 for (MachineFunction::const_iterator MFI = MF->begin(), MFE = MF->end();
660 const MachineBasicBlock &MBB(*MFI);
661 BBInfo &MInfo = MBBInfoMap[&MBB];
662 if (!MInfo.reachable)
664 for (MachineBasicBlock::const_succ_iterator SuI = MBB.succ_begin(),
665 SuE = MBB.succ_end(); SuI != SuE; ++SuI) {
666 BBInfo &SInfo = MBBInfoMap[*SuI];
667 if (SInfo.addPassed(MInfo.regsLiveOut))
672 // Iteratively push vregsPassed to successors. This will converge to the same
673 // final state regardless of DenseSet iteration order.
674 while (!todo.empty()) {
675 const MachineBasicBlock *MBB = *todo.begin();
677 BBInfo &MInfo = MBBInfoMap[MBB];
678 for (MachineBasicBlock::const_succ_iterator SuI = MBB->succ_begin(),
679 SuE = MBB->succ_end(); SuI != SuE; ++SuI) {
682 BBInfo &SInfo = MBBInfoMap[*SuI];
683 if (SInfo.addPassed(MInfo.vregsPassed))
689 // Calculate the minimum vregsPassed set. These are the registers that always
690 // pass live through an MBB. The calculation assumes that calcMaxRegsPassed has
691 // been called earlier.
692 void MachineVerifier::calcMinRegsPassed() {
693 DenseSet<const MachineBasicBlock*> todo;
694 for (MachineFunction::const_iterator MFI = MF->begin(), MFE = MF->end();
698 while (!todo.empty()) {
699 const MachineBasicBlock *MBB = *todo.begin();
701 BBInfo &MInfo = MBBInfoMap[MBB];
703 // Remove entries from vRegsPassed that are not live out from all
704 // reachable predecessors.
706 for (RegSet::iterator I = MInfo.vregsPassed.begin(),
707 E = MInfo.vregsPassed.end(); I != E; ++I) {
708 for (MachineBasicBlock::const_pred_iterator PrI = MBB->pred_begin(),
709 PrE = MBB->pred_end(); PrI != PrE; ++PrI) {
710 BBInfo &PrInfo = MBBInfoMap[*PrI];
711 if (PrInfo.reachable && !PrInfo.isLiveOut(*I)) {
717 // If any regs removed, we need to recheck successors.
719 set_subtract(MInfo.vregsPassed, dead);
720 todo.insert(MBB->succ_begin(), MBB->succ_end());
725 // Check PHI instructions at the beginning of MBB. It is assumed that
726 // calcMinRegsPassed has been run so BBInfo::isLiveOut is valid.
727 void MachineVerifier::checkPHIOps(const MachineBasicBlock *MBB) {
728 for (MachineBasicBlock::const_iterator BBI = MBB->begin(), BBE = MBB->end();
729 BBI != BBE && BBI->getOpcode() == TargetInstrInfo::PHI; ++BBI) {
730 DenseSet<const MachineBasicBlock*> seen;
732 for (unsigned i = 1, e = BBI->getNumOperands(); i != e; i += 2) {
733 unsigned Reg = BBI->getOperand(i).getReg();
734 const MachineBasicBlock *Pre = BBI->getOperand(i + 1).getMBB();
735 if (!Pre->isSuccessor(MBB))
738 BBInfo &PrInfo = MBBInfoMap[Pre];
739 if (PrInfo.reachable && !PrInfo.isLiveOut(Reg))
740 report("PHI operand is not live-out from predecessor",
741 &BBI->getOperand(i), i);
744 // Did we see all predecessors?
745 for (MachineBasicBlock::const_pred_iterator PrI = MBB->pred_begin(),
746 PrE = MBB->pred_end(); PrI != PrE; ++PrI) {
747 if (!seen.count(*PrI)) {
748 report("Missing PHI operand", BBI);
749 *OS << "MBB #" << (*PrI)->getNumber()
750 << " is a predecessor according to the CFG.\n";
756 void MachineVerifier::visitMachineFunctionAfter() {
759 // With the maximal set of vregsPassed we can verify dead-in registers.
760 for (MachineFunction::const_iterator MFI = MF->begin(), MFE = MF->end();
762 BBInfo &MInfo = MBBInfoMap[MFI];
764 // Skip unreachable MBBs.
765 if (!MInfo.reachable)
768 for (MachineBasicBlock::const_pred_iterator PrI = MFI->pred_begin(),
769 PrE = MFI->pred_end(); PrI != PrE; ++PrI) {
770 BBInfo &PrInfo = MBBInfoMap[*PrI];
771 if (!PrInfo.reachable)
774 // Verify physical live-ins. EH landing pads have magic live-ins so we
776 if (!MFI->isLandingPad()) {
777 for (MachineBasicBlock::const_livein_iterator I = MFI->livein_begin(),
778 E = MFI->livein_end(); I != E; ++I) {
779 if (TargetRegisterInfo::isPhysicalRegister(*I) &&
780 !isReserved (*I) && !PrInfo.isLiveOut(*I)) {
781 report("Live-in physical register is not live-out from predecessor",
783 *OS << "Register " << TRI->getName(*I)
784 << " is not live-out from MBB #" << (*PrI)->getNumber()
791 // Verify dead-in virtual registers.
792 if (!allowVirtDoubleDefs) {
793 for (RegMap::iterator I = MInfo.vregsDeadIn.begin(),
794 E = MInfo.vregsDeadIn.end(); I != E; ++I) {
795 // DeadIn register must be in neither regsLiveOut or vregsPassed of
797 if (PrInfo.isLiveOut(I->first)) {
798 report("Live-in virtual register redefined", I->second);
799 *OS << "Register %reg" << I->first
800 << " was live-out from predecessor MBB #"
801 << (*PrI)->getNumber() << ".\n";
810 // With the minimal set of vregsPassed we can verify live-in virtual
811 // registers, including PHI instructions.
812 for (MachineFunction::const_iterator MFI = MF->begin(), MFE = MF->end();
814 BBInfo &MInfo = MBBInfoMap[MFI];
816 // Skip unreachable MBBs.
817 if (!MInfo.reachable)
822 for (MachineBasicBlock::const_pred_iterator PrI = MFI->pred_begin(),
823 PrE = MFI->pred_end(); PrI != PrE; ++PrI) {
824 BBInfo &PrInfo = MBBInfoMap[*PrI];
825 if (!PrInfo.reachable)
828 for (RegMap::iterator I = MInfo.vregsLiveIn.begin(),
829 E = MInfo.vregsLiveIn.end(); I != E; ++I) {
830 if (!PrInfo.isLiveOut(I->first)) {
831 report("Used virtual register is not live-in", I->second);
832 *OS << "Register %reg" << I->first
833 << " is not live-out from predecessor MBB #"
834 << (*PrI)->getNumber()