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1 //===-- Verifier.cpp - Implement the Module Verifier -----------------------==//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines the function verifier interface, that can be used for some
11 // sanity checking of input to the system.
12 //
13 // Note that this does not provide full `Java style' security and verifications,
14 // instead it just tries to ensure that code is well-formed.
15 //
16 //  * Both of a binary operator's parameters are of the same type
17 //  * Verify that the indices of mem access instructions match other operands
18 //  * Verify that arithmetic and other things are only performed on first-class
19 //    types.  Verify that shifts & logicals only happen on integrals f.e.
20 //  * All of the constants in a switch statement are of the correct type
21 //  * The code is in valid SSA form
22 //  * It should be illegal to put a label into any other type (like a structure)
23 //    or to return one. [except constant arrays!]
24 //  * Only phi nodes can be self referential: 'add i32 %0, %0 ; <int>:0' is bad
25 //  * PHI nodes must have an entry for each predecessor, with no extras.
26 //  * PHI nodes must be the first thing in a basic block, all grouped together
27 //  * PHI nodes must have at least one entry
28 //  * All basic blocks should only end with terminator insts, not contain them
29 //  * The entry node to a function must not have predecessors
30 //  * All Instructions must be embedded into a basic block
31 //  * Functions cannot take a void-typed parameter
32 //  * Verify that a function's argument list agrees with it's declared type.
33 //  * It is illegal to specify a name for a void value.
34 //  * It is illegal to have a internal global value with no initializer
35 //  * It is illegal to have a ret instruction that returns a value that does not
36 //    agree with the function return value type.
37 //  * Function call argument types match the function prototype
38 //  * A landing pad is defined by a landingpad instruction, and can be jumped to
39 //    only by the unwind edge of an invoke instruction.
40 //  * A landingpad instruction must be the first non-PHI instruction in the
41 //    block.
42 //  * Landingpad instructions must be in a function with a personality function.
43 //  * All other things that are tested by asserts spread about the code...
44 //
45 //===----------------------------------------------------------------------===//
46 
47 #include "llvm/IR/Verifier.h"
48 #include "llvm/ADT/MapVector.h"
49 #include "llvm/ADT/STLExtras.h"
50 #include "llvm/ADT/SetVector.h"
51 #include "llvm/ADT/SmallPtrSet.h"
52 #include "llvm/ADT/SmallVector.h"
53 #include "llvm/ADT/StringExtras.h"
54 #include "llvm/IR/CFG.h"
55 #include "llvm/IR/CallSite.h"
56 #include "llvm/IR/CallingConv.h"
57 #include "llvm/IR/ConstantRange.h"
58 #include "llvm/IR/Constants.h"
59 #include "llvm/IR/DataLayout.h"
60 #include "llvm/IR/DebugInfo.h"
61 #include "llvm/IR/DerivedTypes.h"
62 #include "llvm/IR/DiagnosticInfo.h"
63 #include "llvm/IR/Dominators.h"
64 #include "llvm/IR/InlineAsm.h"
65 #include "llvm/IR/InstIterator.h"
66 #include "llvm/IR/InstVisitor.h"
67 #include "llvm/IR/IntrinsicInst.h"
68 #include "llvm/IR/LLVMContext.h"
69 #include "llvm/IR/Metadata.h"
70 #include "llvm/IR/Module.h"
71 #include "llvm/IR/ModuleSlotTracker.h"
72 #include "llvm/IR/PassManager.h"
73 #include "llvm/IR/Statepoint.h"
74 #include "llvm/Pass.h"
75 #include "llvm/Support/CommandLine.h"
76 #include "llvm/Support/Debug.h"
77 #include "llvm/Support/ErrorHandling.h"
78 #include "llvm/Support/raw_ostream.h"
79 #include <algorithm>
80 #include <cstdarg>
81 using namespace llvm;
82 
83 static cl::opt<bool> VerifyDebugInfo("verify-debug-info", cl::init(true));
84 
85 namespace {
86 struct VerifierSupport {
87   raw_ostream *OS;
88   const Module *M = nullptr;
89   Optional<ModuleSlotTracker> MST;
90 
91   /// Track the brokenness of the module while recursively visiting.
92   bool Broken = false;
93   /// Broken debug info can be "recovered" from by stripping the debug info.
94   bool BrokenDebugInfo = false;
95   /// Whether to treat broken debug info as an error.
96   bool TreatBrokenDebugInfoAsError = true;
97 
VerifierSupport__anon51203d770111::VerifierSupport98   explicit VerifierSupport(raw_ostream *OS) : OS(OS) {}
99 
100 private:
Write__anon51203d770111::VerifierSupport101   template <class NodeTy> void Write(const ilist_iterator<NodeTy> &I) {
102     Write(&*I);
103   }
104 
Write__anon51203d770111::VerifierSupport105   void Write(const Module *M) {
106     if (!M)
107       return;
108     *OS << "; ModuleID = '" << M->getModuleIdentifier() << "'\n";
109   }
110 
Write__anon51203d770111::VerifierSupport111   void Write(const Value *V) {
112     if (!V)
113       return;
114     if (isa<Instruction>(V)) {
115       V->print(*OS, *MST);
116       *OS << '\n';
117     } else {
118       V->printAsOperand(*OS, true, *MST);
119       *OS << '\n';
120     }
121   }
Write__anon51203d770111::VerifierSupport122   void Write(ImmutableCallSite CS) {
123     Write(CS.getInstruction());
124   }
125 
Write__anon51203d770111::VerifierSupport126   void Write(const Metadata *MD) {
127     if (!MD)
128       return;
129     MD->print(*OS, *MST, M);
130     *OS << '\n';
131   }
132 
Write__anon51203d770111::VerifierSupport133   template <class T> void Write(const MDTupleTypedArrayWrapper<T> &MD) {
134     Write(MD.get());
135   }
136 
Write__anon51203d770111::VerifierSupport137   void Write(const NamedMDNode *NMD) {
138     if (!NMD)
139       return;
140     NMD->print(*OS, *MST);
141     *OS << '\n';
142   }
143 
Write__anon51203d770111::VerifierSupport144   void Write(Type *T) {
145     if (!T)
146       return;
147     *OS << ' ' << *T;
148   }
149 
Write__anon51203d770111::VerifierSupport150   void Write(const Comdat *C) {
151     if (!C)
152       return;
153     *OS << *C;
154   }
155 
Write__anon51203d770111::VerifierSupport156   template <typename T> void Write(ArrayRef<T> Vs) {
157     for (const T &V : Vs)
158       Write(V);
159   }
160 
161   template <typename T1, typename... Ts>
WriteTs__anon51203d770111::VerifierSupport162   void WriteTs(const T1 &V1, const Ts &... Vs) {
163     Write(V1);
164     WriteTs(Vs...);
165   }
166 
WriteTs__anon51203d770111::VerifierSupport167   template <typename... Ts> void WriteTs() {}
168 
169 public:
170   /// \brief A check failed, so printout out the condition and the message.
171   ///
172   /// This provides a nice place to put a breakpoint if you want to see why
173   /// something is not correct.
CheckFailed__anon51203d770111::VerifierSupport174   void CheckFailed(const Twine &Message) {
175     if (OS)
176       *OS << Message << '\n';
177     Broken = true;
178   }
179 
180   /// \brief A check failed (with values to print).
181   ///
182   /// This calls the Message-only version so that the above is easier to set a
183   /// breakpoint on.
184   template <typename T1, typename... Ts>
CheckFailed__anon51203d770111::VerifierSupport185   void CheckFailed(const Twine &Message, const T1 &V1, const Ts &... Vs) {
186     CheckFailed(Message);
187     if (OS)
188       WriteTs(V1, Vs...);
189   }
190 
191   /// A debug info check failed.
DebugInfoCheckFailed__anon51203d770111::VerifierSupport192   void DebugInfoCheckFailed(const Twine &Message) {
193     if (OS)
194       *OS << Message << '\n';
195     Broken |= TreatBrokenDebugInfoAsError;
196     BrokenDebugInfo = true;
197   }
198 
199   /// A debug info check failed (with values to print).
200   template <typename T1, typename... Ts>
DebugInfoCheckFailed__anon51203d770111::VerifierSupport201   void DebugInfoCheckFailed(const Twine &Message, const T1 &V1,
202                             const Ts &... Vs) {
203     DebugInfoCheckFailed(Message);
204     if (OS)
205       WriteTs(V1, Vs...);
206   }
207 };
208 
209 class Verifier : public InstVisitor<Verifier>, VerifierSupport {
210   friend class InstVisitor<Verifier>;
211 
212   LLVMContext *Context;
213   DominatorTree DT;
214 
215   /// \brief When verifying a basic block, keep track of all of the
216   /// instructions we have seen so far.
217   ///
218   /// This allows us to do efficient dominance checks for the case when an
219   /// instruction has an operand that is an instruction in the same block.
220   SmallPtrSet<Instruction *, 16> InstsInThisBlock;
221 
222   /// \brief Keep track of the metadata nodes that have been checked already.
223   SmallPtrSet<const Metadata *, 32> MDNodes;
224 
225   /// Track all DICompileUnits visited.
226   SmallPtrSet<const Metadata *, 2> CUVisited;
227 
228   /// \brief The result type for a landingpad.
229   Type *LandingPadResultTy;
230 
231   /// \brief Whether we've seen a call to @llvm.localescape in this function
232   /// already.
233   bool SawFrameEscape;
234 
235   /// Stores the count of how many objects were passed to llvm.localescape for a
236   /// given function and the largest index passed to llvm.localrecover.
237   DenseMap<Function *, std::pair<unsigned, unsigned>> FrameEscapeInfo;
238 
239   // Maps catchswitches and cleanuppads that unwind to siblings to the
240   // terminators that indicate the unwind, used to detect cycles therein.
241   MapVector<Instruction *, TerminatorInst *> SiblingFuncletInfo;
242 
243   /// Cache of constants visited in search of ConstantExprs.
244   SmallPtrSet<const Constant *, 32> ConstantExprVisited;
245 
246   /// Cache of declarations of the llvm.experimental.deoptimize.<ty> intrinsic.
247   SmallVector<const Function *, 4> DeoptimizeDeclarations;
248 
249   // Verify that this GlobalValue is only used in this module.
250   // This map is used to avoid visiting uses twice. We can arrive at a user
251   // twice, if they have multiple operands. In particular for very large
252   // constant expressions, we can arrive at a particular user many times.
253   SmallPtrSet<const Value *, 32> GlobalValueVisited;
254 
255   void checkAtomicMemAccessSize(const Module *M, Type *Ty,
256                                 const Instruction *I);
257 
updateModule(const Module * NewM)258   void updateModule(const Module *NewM) {
259     if (M == NewM)
260       return;
261     MST.emplace(NewM);
262     M = NewM;
263   }
264 
265 public:
Verifier(raw_ostream * OS,bool ShouldTreatBrokenDebugInfoAsError)266   explicit Verifier(raw_ostream *OS, bool ShouldTreatBrokenDebugInfoAsError)
267       : VerifierSupport(OS), Context(nullptr), LandingPadResultTy(nullptr),
268         SawFrameEscape(false) {
269     TreatBrokenDebugInfoAsError = ShouldTreatBrokenDebugInfoAsError;
270   }
271 
hasBrokenDebugInfo() const272   bool hasBrokenDebugInfo() const { return BrokenDebugInfo; }
273 
verify(const Function & F)274   bool verify(const Function &F) {
275     updateModule(F.getParent());
276     Context = &M->getContext();
277 
278     // First ensure the function is well-enough formed to compute dominance
279     // information, and directly compute a dominance tree. We don't rely on the
280     // pass manager to provide this as it isolates us from a potentially
281     // out-of-date dominator tree and makes it significantly more complex to run
282     // this code outside of a pass manager.
283     // FIXME: It's really gross that we have to cast away constness here.
284     if (!F.empty())
285       DT.recalculate(const_cast<Function &>(F));
286 
287     for (const BasicBlock &BB : F) {
288       if (!BB.empty() && BB.back().isTerminator())
289         continue;
290 
291       if (OS) {
292         *OS << "Basic Block in function '" << F.getName()
293             << "' does not have terminator!\n";
294         BB.printAsOperand(*OS, true, *MST);
295         *OS << "\n";
296       }
297       return false;
298     }
299 
300     Broken = false;
301     // FIXME: We strip const here because the inst visitor strips const.
302     visit(const_cast<Function &>(F));
303     verifySiblingFuncletUnwinds();
304     InstsInThisBlock.clear();
305     LandingPadResultTy = nullptr;
306     SawFrameEscape = false;
307     SiblingFuncletInfo.clear();
308 
309     return !Broken;
310   }
311 
verify(const Module & M)312   bool verify(const Module &M) {
313     updateModule(&M);
314     Context = &M.getContext();
315     Broken = false;
316 
317     // Collect all declarations of the llvm.experimental.deoptimize intrinsic.
318     for (const Function &F : M)
319       if (F.getIntrinsicID() == Intrinsic::experimental_deoptimize)
320         DeoptimizeDeclarations.push_back(&F);
321 
322     // Now that we've visited every function, verify that we never asked to
323     // recover a frame index that wasn't escaped.
324     verifyFrameRecoverIndices();
325     for (const GlobalVariable &GV : M.globals())
326       visitGlobalVariable(GV);
327 
328     for (const GlobalAlias &GA : M.aliases())
329       visitGlobalAlias(GA);
330 
331     for (const NamedMDNode &NMD : M.named_metadata())
332       visitNamedMDNode(NMD);
333 
334     for (const StringMapEntry<Comdat> &SMEC : M.getComdatSymbolTable())
335       visitComdat(SMEC.getValue());
336 
337     visitModuleFlags(M);
338     visitModuleIdents(M);
339 
340     verifyCompileUnits();
341 
342     verifyDeoptimizeCallingConvs();
343 
344     return !Broken;
345   }
346 
347 private:
348   // Verification methods...
349   void visitGlobalValue(const GlobalValue &GV);
350   void visitGlobalVariable(const GlobalVariable &GV);
351   void visitGlobalAlias(const GlobalAlias &GA);
352   void visitAliaseeSubExpr(const GlobalAlias &A, const Constant &C);
353   void visitAliaseeSubExpr(SmallPtrSetImpl<const GlobalAlias *> &Visited,
354                            const GlobalAlias &A, const Constant &C);
355   void visitNamedMDNode(const NamedMDNode &NMD);
356   void visitMDNode(const MDNode &MD);
357   void visitMetadataAsValue(const MetadataAsValue &MD, Function *F);
358   void visitValueAsMetadata(const ValueAsMetadata &MD, Function *F);
359   void visitComdat(const Comdat &C);
360   void visitModuleIdents(const Module &M);
361   void visitModuleFlags(const Module &M);
362   void visitModuleFlag(const MDNode *Op,
363                        DenseMap<const MDString *, const MDNode *> &SeenIDs,
364                        SmallVectorImpl<const MDNode *> &Requirements);
365   void visitFunction(const Function &F);
366   void visitBasicBlock(BasicBlock &BB);
367   void visitRangeMetadata(Instruction& I, MDNode* Range, Type* Ty);
368   void visitDereferenceableMetadata(Instruction& I, MDNode* MD);
369 
370   template <class Ty> bool isValidMetadataArray(const MDTuple &N);
371 #define HANDLE_SPECIALIZED_MDNODE_LEAF(CLASS) void visit##CLASS(const CLASS &N);
372 #include "llvm/IR/Metadata.def"
373   void visitDIScope(const DIScope &N);
374   void visitDIVariable(const DIVariable &N);
375   void visitDILexicalBlockBase(const DILexicalBlockBase &N);
376   void visitDITemplateParameter(const DITemplateParameter &N);
377 
378   void visitTemplateParams(const MDNode &N, const Metadata &RawParams);
379 
380   // InstVisitor overrides...
381   using InstVisitor<Verifier>::visit;
382   void visit(Instruction &I);
383 
384   void visitTruncInst(TruncInst &I);
385   void visitZExtInst(ZExtInst &I);
386   void visitSExtInst(SExtInst &I);
387   void visitFPTruncInst(FPTruncInst &I);
388   void visitFPExtInst(FPExtInst &I);
389   void visitFPToUIInst(FPToUIInst &I);
390   void visitFPToSIInst(FPToSIInst &I);
391   void visitUIToFPInst(UIToFPInst &I);
392   void visitSIToFPInst(SIToFPInst &I);
393   void visitIntToPtrInst(IntToPtrInst &I);
394   void visitPtrToIntInst(PtrToIntInst &I);
395   void visitBitCastInst(BitCastInst &I);
396   void visitAddrSpaceCastInst(AddrSpaceCastInst &I);
397   void visitPHINode(PHINode &PN);
398   void visitBinaryOperator(BinaryOperator &B);
399   void visitICmpInst(ICmpInst &IC);
400   void visitFCmpInst(FCmpInst &FC);
401   void visitExtractElementInst(ExtractElementInst &EI);
402   void visitInsertElementInst(InsertElementInst &EI);
403   void visitShuffleVectorInst(ShuffleVectorInst &EI);
visitVAArgInst(VAArgInst & VAA)404   void visitVAArgInst(VAArgInst &VAA) { visitInstruction(VAA); }
405   void visitCallInst(CallInst &CI);
406   void visitInvokeInst(InvokeInst &II);
407   void visitGetElementPtrInst(GetElementPtrInst &GEP);
408   void visitLoadInst(LoadInst &LI);
409   void visitStoreInst(StoreInst &SI);
410   void verifyDominatesUse(Instruction &I, unsigned i);
411   void visitInstruction(Instruction &I);
412   void visitTerminatorInst(TerminatorInst &I);
413   void visitBranchInst(BranchInst &BI);
414   void visitReturnInst(ReturnInst &RI);
415   void visitSwitchInst(SwitchInst &SI);
416   void visitIndirectBrInst(IndirectBrInst &BI);
417   void visitSelectInst(SelectInst &SI);
418   void visitUserOp1(Instruction &I);
visitUserOp2(Instruction & I)419   void visitUserOp2(Instruction &I) { visitUserOp1(I); }
420   void visitIntrinsicCallSite(Intrinsic::ID ID, CallSite CS);
421   template <class DbgIntrinsicTy>
422   void visitDbgIntrinsic(StringRef Kind, DbgIntrinsicTy &DII);
423   void visitAtomicCmpXchgInst(AtomicCmpXchgInst &CXI);
424   void visitAtomicRMWInst(AtomicRMWInst &RMWI);
425   void visitFenceInst(FenceInst &FI);
426   void visitAllocaInst(AllocaInst &AI);
427   void visitExtractValueInst(ExtractValueInst &EVI);
428   void visitInsertValueInst(InsertValueInst &IVI);
429   void visitEHPadPredecessors(Instruction &I);
430   void visitLandingPadInst(LandingPadInst &LPI);
431   void visitCatchPadInst(CatchPadInst &CPI);
432   void visitCatchReturnInst(CatchReturnInst &CatchReturn);
433   void visitCleanupPadInst(CleanupPadInst &CPI);
434   void visitFuncletPadInst(FuncletPadInst &FPI);
435   void visitCatchSwitchInst(CatchSwitchInst &CatchSwitch);
436   void visitCleanupReturnInst(CleanupReturnInst &CRI);
437 
438   void verifyCallSite(CallSite CS);
439   void verifySwiftErrorCallSite(CallSite CS, const Value *SwiftErrorVal);
440   void verifySwiftErrorValue(const Value *SwiftErrorVal);
441   void verifyMustTailCall(CallInst &CI);
442   bool performTypeCheck(Intrinsic::ID ID, Function *F, Type *Ty, int VT,
443                         unsigned ArgNo, std::string &Suffix);
444   bool verifyAttributeCount(AttributeSet Attrs, unsigned Params);
445   void verifyAttributeTypes(AttributeSet Attrs, unsigned Idx, bool isFunction,
446                             const Value *V);
447   void verifyParameterAttrs(AttributeSet Attrs, unsigned Idx, Type *Ty,
448                             bool isReturnValue, const Value *V);
449   void verifyFunctionAttrs(FunctionType *FT, AttributeSet Attrs,
450                            const Value *V);
451   void verifyFunctionMetadata(ArrayRef<std::pair<unsigned, MDNode *>> MDs);
452 
453   void visitConstantExprsRecursively(const Constant *EntryC);
454   void visitConstantExpr(const ConstantExpr *CE);
455   void verifyStatepoint(ImmutableCallSite CS);
456   void verifyFrameRecoverIndices();
457   void verifySiblingFuncletUnwinds();
458 
459   void verifyBitPieceExpression(const DbgInfoIntrinsic &I);
460 
461   /// Module-level debug info verification...
462   void verifyCompileUnits();
463 
464   /// Module-level verification that all @llvm.experimental.deoptimize
465   /// declarations share the same calling convention.
466   void verifyDeoptimizeCallingConvs();
467 };
468 } // End anonymous namespace
469 
470 /// We know that cond should be true, if not print an error message.
471 #define Assert(C, ...) \
472   do { if (!(C)) { CheckFailed(__VA_ARGS__); return; } } while (0)
473 
474 /// We know that a debug info condition should be true, if not print
475 /// an error message.
476 #define AssertDI(C, ...) \
477   do { if (!(C)) { DebugInfoCheckFailed(__VA_ARGS__); return; } } while (0)
478 
479 
visit(Instruction & I)480 void Verifier::visit(Instruction &I) {
481   for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
482     Assert(I.getOperand(i) != nullptr, "Operand is null", &I);
483   InstVisitor<Verifier>::visit(I);
484 }
485 
486 // Helper to recursively iterate over indirect users. By
487 // returning false, the callback can ask to stop recursing
488 // further.
forEachUser(const Value * User,SmallPtrSet<const Value *,32> & Visited,llvm::function_ref<bool (const Value *)> Callback)489 static void forEachUser(const Value *User,
490                         SmallPtrSet<const Value *, 32> &Visited,
491                         llvm::function_ref<bool(const Value *)> Callback) {
492   if (!Visited.insert(User).second)
493     return;
494   for (const Value *TheNextUser : User->materialized_users())
495     if (Callback(TheNextUser))
496       forEachUser(TheNextUser, Visited, Callback);
497 }
498 
visitGlobalValue(const GlobalValue & GV)499 void Verifier::visitGlobalValue(const GlobalValue &GV) {
500   Assert(!GV.isDeclaration() || GV.hasValidDeclarationLinkage(),
501          "Global is external, but doesn't have external or weak linkage!", &GV);
502 
503   Assert(GV.getAlignment() <= Value::MaximumAlignment,
504          "huge alignment values are unsupported", &GV);
505   Assert(!GV.hasAppendingLinkage() || isa<GlobalVariable>(GV),
506          "Only global variables can have appending linkage!", &GV);
507 
508   if (GV.hasAppendingLinkage()) {
509     const GlobalVariable *GVar = dyn_cast<GlobalVariable>(&GV);
510     Assert(GVar && GVar->getValueType()->isArrayTy(),
511            "Only global arrays can have appending linkage!", GVar);
512   }
513 
514   if (GV.isDeclarationForLinker())
515     Assert(!GV.hasComdat(), "Declaration may not be in a Comdat!", &GV);
516 
517   forEachUser(&GV, GlobalValueVisited, [&](const Value *V) -> bool {
518     if (const Instruction *I = dyn_cast<Instruction>(V)) {
519       if (!I->getParent() || !I->getParent()->getParent())
520         CheckFailed("Global is referenced by parentless instruction!", &GV,
521                     M, I);
522       else if (I->getParent()->getParent()->getParent() != M)
523         CheckFailed("Global is referenced in a different module!", &GV,
524                     M, I, I->getParent()->getParent(),
525                     I->getParent()->getParent()->getParent());
526       return false;
527     } else if (const Function *F = dyn_cast<Function>(V)) {
528       if (F->getParent() != M)
529         CheckFailed("Global is used by function in a different module", &GV,
530                     M, F, F->getParent());
531       return false;
532     }
533     return true;
534   });
535 }
536 
visitGlobalVariable(const GlobalVariable & GV)537 void Verifier::visitGlobalVariable(const GlobalVariable &GV) {
538   if (GV.hasInitializer()) {
539     Assert(GV.getInitializer()->getType() == GV.getValueType(),
540            "Global variable initializer type does not match global "
541            "variable type!",
542            &GV);
543 
544     // If the global has common linkage, it must have a zero initializer and
545     // cannot be constant.
546     if (GV.hasCommonLinkage()) {
547       Assert(GV.getInitializer()->isNullValue(),
548              "'common' global must have a zero initializer!", &GV);
549       Assert(!GV.isConstant(), "'common' global may not be marked constant!",
550              &GV);
551       Assert(!GV.hasComdat(), "'common' global may not be in a Comdat!", &GV);
552     }
553   }
554 
555   if (GV.hasName() && (GV.getName() == "llvm.global_ctors" ||
556                        GV.getName() == "llvm.global_dtors")) {
557     Assert(!GV.hasInitializer() || GV.hasAppendingLinkage(),
558            "invalid linkage for intrinsic global variable", &GV);
559     // Don't worry about emitting an error for it not being an array,
560     // visitGlobalValue will complain on appending non-array.
561     if (ArrayType *ATy = dyn_cast<ArrayType>(GV.getValueType())) {
562       StructType *STy = dyn_cast<StructType>(ATy->getElementType());
563       PointerType *FuncPtrTy =
564           FunctionType::get(Type::getVoidTy(*Context), false)->getPointerTo();
565       // FIXME: Reject the 2-field form in LLVM 4.0.
566       Assert(STy &&
567                  (STy->getNumElements() == 2 || STy->getNumElements() == 3) &&
568                  STy->getTypeAtIndex(0u)->isIntegerTy(32) &&
569                  STy->getTypeAtIndex(1) == FuncPtrTy,
570              "wrong type for intrinsic global variable", &GV);
571       if (STy->getNumElements() == 3) {
572         Type *ETy = STy->getTypeAtIndex(2);
573         Assert(ETy->isPointerTy() &&
574                    cast<PointerType>(ETy)->getElementType()->isIntegerTy(8),
575                "wrong type for intrinsic global variable", &GV);
576       }
577     }
578   }
579 
580   if (GV.hasName() && (GV.getName() == "llvm.used" ||
581                        GV.getName() == "llvm.compiler.used")) {
582     Assert(!GV.hasInitializer() || GV.hasAppendingLinkage(),
583            "invalid linkage for intrinsic global variable", &GV);
584     Type *GVType = GV.getValueType();
585     if (ArrayType *ATy = dyn_cast<ArrayType>(GVType)) {
586       PointerType *PTy = dyn_cast<PointerType>(ATy->getElementType());
587       Assert(PTy, "wrong type for intrinsic global variable", &GV);
588       if (GV.hasInitializer()) {
589         const Constant *Init = GV.getInitializer();
590         const ConstantArray *InitArray = dyn_cast<ConstantArray>(Init);
591         Assert(InitArray, "wrong initalizer for intrinsic global variable",
592                Init);
593         for (Value *Op : InitArray->operands()) {
594           Value *V = Op->stripPointerCastsNoFollowAliases();
595           Assert(isa<GlobalVariable>(V) || isa<Function>(V) ||
596                      isa<GlobalAlias>(V),
597                  "invalid llvm.used member", V);
598           Assert(V->hasName(), "members of llvm.used must be named", V);
599         }
600       }
601     }
602   }
603 
604   Assert(!GV.hasDLLImportStorageClass() ||
605              (GV.isDeclaration() && GV.hasExternalLinkage()) ||
606              GV.hasAvailableExternallyLinkage(),
607          "Global is marked as dllimport, but not external", &GV);
608 
609   if (!GV.hasInitializer()) {
610     visitGlobalValue(GV);
611     return;
612   }
613 
614   // Walk any aggregate initializers looking for bitcasts between address spaces
615   visitConstantExprsRecursively(GV.getInitializer());
616 
617   visitGlobalValue(GV);
618 }
619 
visitAliaseeSubExpr(const GlobalAlias & GA,const Constant & C)620 void Verifier::visitAliaseeSubExpr(const GlobalAlias &GA, const Constant &C) {
621   SmallPtrSet<const GlobalAlias*, 4> Visited;
622   Visited.insert(&GA);
623   visitAliaseeSubExpr(Visited, GA, C);
624 }
625 
visitAliaseeSubExpr(SmallPtrSetImpl<const GlobalAlias * > & Visited,const GlobalAlias & GA,const Constant & C)626 void Verifier::visitAliaseeSubExpr(SmallPtrSetImpl<const GlobalAlias*> &Visited,
627                                    const GlobalAlias &GA, const Constant &C) {
628   if (const auto *GV = dyn_cast<GlobalValue>(&C)) {
629     Assert(!GV->isDeclarationForLinker(), "Alias must point to a definition",
630            &GA);
631 
632     if (const auto *GA2 = dyn_cast<GlobalAlias>(GV)) {
633       Assert(Visited.insert(GA2).second, "Aliases cannot form a cycle", &GA);
634 
635       Assert(!GA2->isInterposable(), "Alias cannot point to an interposable alias",
636              &GA);
637     } else {
638       // Only continue verifying subexpressions of GlobalAliases.
639       // Do not recurse into global initializers.
640       return;
641     }
642   }
643 
644   if (const auto *CE = dyn_cast<ConstantExpr>(&C))
645     visitConstantExprsRecursively(CE);
646 
647   for (const Use &U : C.operands()) {
648     Value *V = &*U;
649     if (const auto *GA2 = dyn_cast<GlobalAlias>(V))
650       visitAliaseeSubExpr(Visited, GA, *GA2->getAliasee());
651     else if (const auto *C2 = dyn_cast<Constant>(V))
652       visitAliaseeSubExpr(Visited, GA, *C2);
653   }
654 }
655 
visitGlobalAlias(const GlobalAlias & GA)656 void Verifier::visitGlobalAlias(const GlobalAlias &GA) {
657   Assert(GlobalAlias::isValidLinkage(GA.getLinkage()),
658          "Alias should have private, internal, linkonce, weak, linkonce_odr, "
659          "weak_odr, or external linkage!",
660          &GA);
661   const Constant *Aliasee = GA.getAliasee();
662   Assert(Aliasee, "Aliasee cannot be NULL!", &GA);
663   Assert(GA.getType() == Aliasee->getType(),
664          "Alias and aliasee types should match!", &GA);
665 
666   Assert(isa<GlobalValue>(Aliasee) || isa<ConstantExpr>(Aliasee),
667          "Aliasee should be either GlobalValue or ConstantExpr", &GA);
668 
669   visitAliaseeSubExpr(GA, *Aliasee);
670 
671   visitGlobalValue(GA);
672 }
673 
visitNamedMDNode(const NamedMDNode & NMD)674 void Verifier::visitNamedMDNode(const NamedMDNode &NMD) {
675   for (const MDNode *MD : NMD.operands()) {
676     if (NMD.getName() == "llvm.dbg.cu") {
677       AssertDI(MD && isa<DICompileUnit>(MD), "invalid compile unit", &NMD, MD);
678     }
679 
680     if (!MD)
681       continue;
682 
683     visitMDNode(*MD);
684   }
685 }
686 
visitMDNode(const MDNode & MD)687 void Verifier::visitMDNode(const MDNode &MD) {
688   // Only visit each node once.  Metadata can be mutually recursive, so this
689   // avoids infinite recursion here, as well as being an optimization.
690   if (!MDNodes.insert(&MD).second)
691     return;
692 
693   switch (MD.getMetadataID()) {
694   default:
695     llvm_unreachable("Invalid MDNode subclass");
696   case Metadata::MDTupleKind:
697     break;
698 #define HANDLE_SPECIALIZED_MDNODE_LEAF(CLASS)                                  \
699   case Metadata::CLASS##Kind:                                                  \
700     visit##CLASS(cast<CLASS>(MD));                                             \
701     break;
702 #include "llvm/IR/Metadata.def"
703   }
704 
705   for (const Metadata *Op : MD.operands()) {
706     if (!Op)
707       continue;
708     Assert(!isa<LocalAsMetadata>(Op), "Invalid operand for global metadata!",
709            &MD, Op);
710     if (auto *N = dyn_cast<MDNode>(Op)) {
711       visitMDNode(*N);
712       continue;
713     }
714     if (auto *V = dyn_cast<ValueAsMetadata>(Op)) {
715       visitValueAsMetadata(*V, nullptr);
716       continue;
717     }
718   }
719 
720   // Check these last, so we diagnose problems in operands first.
721   Assert(!MD.isTemporary(), "Expected no forward declarations!", &MD);
722   Assert(MD.isResolved(), "All nodes should be resolved!", &MD);
723 }
724 
visitValueAsMetadata(const ValueAsMetadata & MD,Function * F)725 void Verifier::visitValueAsMetadata(const ValueAsMetadata &MD, Function *F) {
726   Assert(MD.getValue(), "Expected valid value", &MD);
727   Assert(!MD.getValue()->getType()->isMetadataTy(),
728          "Unexpected metadata round-trip through values", &MD, MD.getValue());
729 
730   auto *L = dyn_cast<LocalAsMetadata>(&MD);
731   if (!L)
732     return;
733 
734   Assert(F, "function-local metadata used outside a function", L);
735 
736   // If this was an instruction, bb, or argument, verify that it is in the
737   // function that we expect.
738   Function *ActualF = nullptr;
739   if (Instruction *I = dyn_cast<Instruction>(L->getValue())) {
740     Assert(I->getParent(), "function-local metadata not in basic block", L, I);
741     ActualF = I->getParent()->getParent();
742   } else if (BasicBlock *BB = dyn_cast<BasicBlock>(L->getValue()))
743     ActualF = BB->getParent();
744   else if (Argument *A = dyn_cast<Argument>(L->getValue()))
745     ActualF = A->getParent();
746   assert(ActualF && "Unimplemented function local metadata case!");
747 
748   Assert(ActualF == F, "function-local metadata used in wrong function", L);
749 }
750 
visitMetadataAsValue(const MetadataAsValue & MDV,Function * F)751 void Verifier::visitMetadataAsValue(const MetadataAsValue &MDV, Function *F) {
752   Metadata *MD = MDV.getMetadata();
753   if (auto *N = dyn_cast<MDNode>(MD)) {
754     visitMDNode(*N);
755     return;
756   }
757 
758   // Only visit each node once.  Metadata can be mutually recursive, so this
759   // avoids infinite recursion here, as well as being an optimization.
760   if (!MDNodes.insert(MD).second)
761     return;
762 
763   if (auto *V = dyn_cast<ValueAsMetadata>(MD))
764     visitValueAsMetadata(*V, F);
765 }
766 
isType(const Metadata * MD)767 static bool isType(const Metadata *MD) { return !MD || isa<DIType>(MD); }
isScope(const Metadata * MD)768 static bool isScope(const Metadata *MD) { return !MD || isa<DIScope>(MD); }
isDINode(const Metadata * MD)769 static bool isDINode(const Metadata *MD) { return !MD || isa<DINode>(MD); }
770 
771 template <class Ty>
isValidMetadataArrayImpl(const MDTuple & N,bool AllowNull)772 bool isValidMetadataArrayImpl(const MDTuple &N, bool AllowNull) {
773   for (Metadata *MD : N.operands()) {
774     if (MD) {
775       if (!isa<Ty>(MD))
776         return false;
777     } else {
778       if (!AllowNull)
779         return false;
780     }
781   }
782   return true;
783 }
784 
785 template <class Ty>
isValidMetadataArray(const MDTuple & N)786 bool isValidMetadataArray(const MDTuple &N) {
787   return isValidMetadataArrayImpl<Ty>(N, /* AllowNull */ false);
788 }
789 
790 template <class Ty>
isValidMetadataNullArray(const MDTuple & N)791 bool isValidMetadataNullArray(const MDTuple &N) {
792   return isValidMetadataArrayImpl<Ty>(N, /* AllowNull */ true);
793 }
794 
visitDILocation(const DILocation & N)795 void Verifier::visitDILocation(const DILocation &N) {
796   AssertDI(N.getRawScope() && isa<DILocalScope>(N.getRawScope()),
797            "location requires a valid scope", &N, N.getRawScope());
798   if (auto *IA = N.getRawInlinedAt())
799     AssertDI(isa<DILocation>(IA), "inlined-at should be a location", &N, IA);
800 }
801 
visitGenericDINode(const GenericDINode & N)802 void Verifier::visitGenericDINode(const GenericDINode &N) {
803   AssertDI(N.getTag(), "invalid tag", &N);
804 }
805 
visitDIScope(const DIScope & N)806 void Verifier::visitDIScope(const DIScope &N) {
807   if (auto *F = N.getRawFile())
808     AssertDI(isa<DIFile>(F), "invalid file", &N, F);
809 }
810 
visitDISubrange(const DISubrange & N)811 void Verifier::visitDISubrange(const DISubrange &N) {
812   AssertDI(N.getTag() == dwarf::DW_TAG_subrange_type, "invalid tag", &N);
813   AssertDI(N.getCount() >= -1, "invalid subrange count", &N);
814 }
815 
visitDIEnumerator(const DIEnumerator & N)816 void Verifier::visitDIEnumerator(const DIEnumerator &N) {
817   AssertDI(N.getTag() == dwarf::DW_TAG_enumerator, "invalid tag", &N);
818 }
819 
visitDIBasicType(const DIBasicType & N)820 void Verifier::visitDIBasicType(const DIBasicType &N) {
821   AssertDI(N.getTag() == dwarf::DW_TAG_base_type ||
822                N.getTag() == dwarf::DW_TAG_unspecified_type,
823            "invalid tag", &N);
824 }
825 
visitDIDerivedType(const DIDerivedType & N)826 void Verifier::visitDIDerivedType(const DIDerivedType &N) {
827   // Common scope checks.
828   visitDIScope(N);
829 
830   AssertDI(N.getTag() == dwarf::DW_TAG_typedef ||
831                N.getTag() == dwarf::DW_TAG_pointer_type ||
832                N.getTag() == dwarf::DW_TAG_ptr_to_member_type ||
833                N.getTag() == dwarf::DW_TAG_reference_type ||
834                N.getTag() == dwarf::DW_TAG_rvalue_reference_type ||
835                N.getTag() == dwarf::DW_TAG_const_type ||
836                N.getTag() == dwarf::DW_TAG_volatile_type ||
837                N.getTag() == dwarf::DW_TAG_restrict_type ||
838                N.getTag() == dwarf::DW_TAG_member ||
839                N.getTag() == dwarf::DW_TAG_inheritance ||
840                N.getTag() == dwarf::DW_TAG_friend,
841            "invalid tag", &N);
842   if (N.getTag() == dwarf::DW_TAG_ptr_to_member_type) {
843     AssertDI(isType(N.getRawExtraData()), "invalid pointer to member type", &N,
844              N.getRawExtraData());
845   }
846 
847   AssertDI(isScope(N.getRawScope()), "invalid scope", &N, N.getRawScope());
848   AssertDI(isType(N.getRawBaseType()), "invalid base type", &N,
849            N.getRawBaseType());
850 }
851 
hasConflictingReferenceFlags(unsigned Flags)852 static bool hasConflictingReferenceFlags(unsigned Flags) {
853   return (Flags & DINode::FlagLValueReference) &&
854          (Flags & DINode::FlagRValueReference);
855 }
856 
visitTemplateParams(const MDNode & N,const Metadata & RawParams)857 void Verifier::visitTemplateParams(const MDNode &N, const Metadata &RawParams) {
858   auto *Params = dyn_cast<MDTuple>(&RawParams);
859   AssertDI(Params, "invalid template params", &N, &RawParams);
860   for (Metadata *Op : Params->operands()) {
861     AssertDI(Op && isa<DITemplateParameter>(Op), "invalid template parameter",
862              &N, Params, Op);
863   }
864 }
865 
visitDICompositeType(const DICompositeType & N)866 void Verifier::visitDICompositeType(const DICompositeType &N) {
867   // Common scope checks.
868   visitDIScope(N);
869 
870   AssertDI(N.getTag() == dwarf::DW_TAG_array_type ||
871                N.getTag() == dwarf::DW_TAG_structure_type ||
872                N.getTag() == dwarf::DW_TAG_union_type ||
873                N.getTag() == dwarf::DW_TAG_enumeration_type ||
874                N.getTag() == dwarf::DW_TAG_class_type,
875            "invalid tag", &N);
876 
877   AssertDI(isScope(N.getRawScope()), "invalid scope", &N, N.getRawScope());
878   AssertDI(isType(N.getRawBaseType()), "invalid base type", &N,
879            N.getRawBaseType());
880 
881   AssertDI(!N.getRawElements() || isa<MDTuple>(N.getRawElements()),
882            "invalid composite elements", &N, N.getRawElements());
883   AssertDI(isType(N.getRawVTableHolder()), "invalid vtable holder", &N,
884            N.getRawVTableHolder());
885   AssertDI(!hasConflictingReferenceFlags(N.getFlags()),
886            "invalid reference flags", &N);
887   if (auto *Params = N.getRawTemplateParams())
888     visitTemplateParams(N, *Params);
889 
890   if (N.getTag() == dwarf::DW_TAG_class_type ||
891       N.getTag() == dwarf::DW_TAG_union_type) {
892     AssertDI(N.getFile() && !N.getFile()->getFilename().empty(),
893              "class/union requires a filename", &N, N.getFile());
894   }
895 }
896 
visitDISubroutineType(const DISubroutineType & N)897 void Verifier::visitDISubroutineType(const DISubroutineType &N) {
898   AssertDI(N.getTag() == dwarf::DW_TAG_subroutine_type, "invalid tag", &N);
899   if (auto *Types = N.getRawTypeArray()) {
900     AssertDI(isa<MDTuple>(Types), "invalid composite elements", &N, Types);
901     for (Metadata *Ty : N.getTypeArray()->operands()) {
902       AssertDI(isType(Ty), "invalid subroutine type ref", &N, Types, Ty);
903     }
904   }
905   AssertDI(!hasConflictingReferenceFlags(N.getFlags()),
906            "invalid reference flags", &N);
907 }
908 
visitDIFile(const DIFile & N)909 void Verifier::visitDIFile(const DIFile &N) {
910   AssertDI(N.getTag() == dwarf::DW_TAG_file_type, "invalid tag", &N);
911 }
912 
visitDICompileUnit(const DICompileUnit & N)913 void Verifier::visitDICompileUnit(const DICompileUnit &N) {
914   AssertDI(N.isDistinct(), "compile units must be distinct", &N);
915   AssertDI(N.getTag() == dwarf::DW_TAG_compile_unit, "invalid tag", &N);
916 
917   // Don't bother verifying the compilation directory or producer string
918   // as those could be empty.
919   AssertDI(N.getRawFile() && isa<DIFile>(N.getRawFile()), "invalid file", &N,
920            N.getRawFile());
921   AssertDI(!N.getFile()->getFilename().empty(), "invalid filename", &N,
922            N.getFile());
923 
924   AssertDI((N.getEmissionKind() <= DICompileUnit::LastEmissionKind),
925            "invalid emission kind", &N);
926 
927   if (auto *Array = N.getRawEnumTypes()) {
928     AssertDI(isa<MDTuple>(Array), "invalid enum list", &N, Array);
929     for (Metadata *Op : N.getEnumTypes()->operands()) {
930       auto *Enum = dyn_cast_or_null<DICompositeType>(Op);
931       AssertDI(Enum && Enum->getTag() == dwarf::DW_TAG_enumeration_type,
932                "invalid enum type", &N, N.getEnumTypes(), Op);
933     }
934   }
935   if (auto *Array = N.getRawRetainedTypes()) {
936     AssertDI(isa<MDTuple>(Array), "invalid retained type list", &N, Array);
937     for (Metadata *Op : N.getRetainedTypes()->operands()) {
938       AssertDI(Op && (isa<DIType>(Op) ||
939                       (isa<DISubprogram>(Op) &&
940                        cast<DISubprogram>(Op)->isDefinition() == false)),
941                "invalid retained type", &N, Op);
942     }
943   }
944   if (auto *Array = N.getRawGlobalVariables()) {
945     AssertDI(isa<MDTuple>(Array), "invalid global variable list", &N, Array);
946     for (Metadata *Op : N.getGlobalVariables()->operands()) {
947       AssertDI(Op && isa<DIGlobalVariable>(Op), "invalid global variable ref",
948                &N, Op);
949     }
950   }
951   if (auto *Array = N.getRawImportedEntities()) {
952     AssertDI(isa<MDTuple>(Array), "invalid imported entity list", &N, Array);
953     for (Metadata *Op : N.getImportedEntities()->operands()) {
954       AssertDI(Op && isa<DIImportedEntity>(Op), "invalid imported entity ref",
955                &N, Op);
956     }
957   }
958   if (auto *Array = N.getRawMacros()) {
959     AssertDI(isa<MDTuple>(Array), "invalid macro list", &N, Array);
960     for (Metadata *Op : N.getMacros()->operands()) {
961       AssertDI(Op && isa<DIMacroNode>(Op), "invalid macro ref", &N, Op);
962     }
963   }
964   CUVisited.insert(&N);
965 }
966 
visitDISubprogram(const DISubprogram & N)967 void Verifier::visitDISubprogram(const DISubprogram &N) {
968   AssertDI(N.getTag() == dwarf::DW_TAG_subprogram, "invalid tag", &N);
969   AssertDI(isScope(N.getRawScope()), "invalid scope", &N, N.getRawScope());
970   if (auto *F = N.getRawFile())
971     AssertDI(isa<DIFile>(F), "invalid file", &N, F);
972   if (auto *T = N.getRawType())
973     AssertDI(isa<DISubroutineType>(T), "invalid subroutine type", &N, T);
974   AssertDI(isType(N.getRawContainingType()), "invalid containing type", &N,
975            N.getRawContainingType());
976   if (auto *Params = N.getRawTemplateParams())
977     visitTemplateParams(N, *Params);
978   if (auto *S = N.getRawDeclaration())
979     AssertDI(isa<DISubprogram>(S) && !cast<DISubprogram>(S)->isDefinition(),
980              "invalid subprogram declaration", &N, S);
981   if (auto *RawVars = N.getRawVariables()) {
982     auto *Vars = dyn_cast<MDTuple>(RawVars);
983     AssertDI(Vars, "invalid variable list", &N, RawVars);
984     for (Metadata *Op : Vars->operands()) {
985       AssertDI(Op && isa<DILocalVariable>(Op), "invalid local variable", &N,
986                Vars, Op);
987     }
988   }
989   AssertDI(!hasConflictingReferenceFlags(N.getFlags()),
990            "invalid reference flags", &N);
991 
992   auto *Unit = N.getRawUnit();
993   if (N.isDefinition()) {
994     // Subprogram definitions (not part of the type hierarchy).
995     AssertDI(N.isDistinct(), "subprogram definitions must be distinct", &N);
996     AssertDI(Unit, "subprogram definitions must have a compile unit", &N);
997     AssertDI(isa<DICompileUnit>(Unit), "invalid unit type", &N, Unit);
998   } else {
999     // Subprogram declarations (part of the type hierarchy).
1000     AssertDI(!Unit, "subprogram declarations must not have a compile unit", &N);
1001   }
1002 }
1003 
visitDILexicalBlockBase(const DILexicalBlockBase & N)1004 void Verifier::visitDILexicalBlockBase(const DILexicalBlockBase &N) {
1005   AssertDI(N.getTag() == dwarf::DW_TAG_lexical_block, "invalid tag", &N);
1006   AssertDI(N.getRawScope() && isa<DILocalScope>(N.getRawScope()),
1007            "invalid local scope", &N, N.getRawScope());
1008 }
1009 
visitDILexicalBlock(const DILexicalBlock & N)1010 void Verifier::visitDILexicalBlock(const DILexicalBlock &N) {
1011   visitDILexicalBlockBase(N);
1012 
1013   AssertDI(N.getLine() || !N.getColumn(),
1014            "cannot have column info without line info", &N);
1015 }
1016 
visitDILexicalBlockFile(const DILexicalBlockFile & N)1017 void Verifier::visitDILexicalBlockFile(const DILexicalBlockFile &N) {
1018   visitDILexicalBlockBase(N);
1019 }
1020 
visitDINamespace(const DINamespace & N)1021 void Verifier::visitDINamespace(const DINamespace &N) {
1022   AssertDI(N.getTag() == dwarf::DW_TAG_namespace, "invalid tag", &N);
1023   if (auto *S = N.getRawScope())
1024     AssertDI(isa<DIScope>(S), "invalid scope ref", &N, S);
1025 }
1026 
visitDIMacro(const DIMacro & N)1027 void Verifier::visitDIMacro(const DIMacro &N) {
1028   AssertDI(N.getMacinfoType() == dwarf::DW_MACINFO_define ||
1029                N.getMacinfoType() == dwarf::DW_MACINFO_undef,
1030            "invalid macinfo type", &N);
1031   AssertDI(!N.getName().empty(), "anonymous macro", &N);
1032   if (!N.getValue().empty()) {
1033     assert(N.getValue().data()[0] != ' ' && "Macro value has a space prefix");
1034   }
1035 }
1036 
visitDIMacroFile(const DIMacroFile & N)1037 void Verifier::visitDIMacroFile(const DIMacroFile &N) {
1038   AssertDI(N.getMacinfoType() == dwarf::DW_MACINFO_start_file,
1039            "invalid macinfo type", &N);
1040   if (auto *F = N.getRawFile())
1041     AssertDI(isa<DIFile>(F), "invalid file", &N, F);
1042 
1043   if (auto *Array = N.getRawElements()) {
1044     AssertDI(isa<MDTuple>(Array), "invalid macro list", &N, Array);
1045     for (Metadata *Op : N.getElements()->operands()) {
1046       AssertDI(Op && isa<DIMacroNode>(Op), "invalid macro ref", &N, Op);
1047     }
1048   }
1049 }
1050 
visitDIModule(const DIModule & N)1051 void Verifier::visitDIModule(const DIModule &N) {
1052   AssertDI(N.getTag() == dwarf::DW_TAG_module, "invalid tag", &N);
1053   AssertDI(!N.getName().empty(), "anonymous module", &N);
1054 }
1055 
visitDITemplateParameter(const DITemplateParameter & N)1056 void Verifier::visitDITemplateParameter(const DITemplateParameter &N) {
1057   AssertDI(isType(N.getRawType()), "invalid type ref", &N, N.getRawType());
1058 }
1059 
visitDITemplateTypeParameter(const DITemplateTypeParameter & N)1060 void Verifier::visitDITemplateTypeParameter(const DITemplateTypeParameter &N) {
1061   visitDITemplateParameter(N);
1062 
1063   AssertDI(N.getTag() == dwarf::DW_TAG_template_type_parameter, "invalid tag",
1064            &N);
1065 }
1066 
visitDITemplateValueParameter(const DITemplateValueParameter & N)1067 void Verifier::visitDITemplateValueParameter(
1068     const DITemplateValueParameter &N) {
1069   visitDITemplateParameter(N);
1070 
1071   AssertDI(N.getTag() == dwarf::DW_TAG_template_value_parameter ||
1072                N.getTag() == dwarf::DW_TAG_GNU_template_template_param ||
1073                N.getTag() == dwarf::DW_TAG_GNU_template_parameter_pack,
1074            "invalid tag", &N);
1075 }
1076 
visitDIVariable(const DIVariable & N)1077 void Verifier::visitDIVariable(const DIVariable &N) {
1078   if (auto *S = N.getRawScope())
1079     AssertDI(isa<DIScope>(S), "invalid scope", &N, S);
1080   AssertDI(isType(N.getRawType()), "invalid type ref", &N, N.getRawType());
1081   if (auto *F = N.getRawFile())
1082     AssertDI(isa<DIFile>(F), "invalid file", &N, F);
1083 }
1084 
visitDIGlobalVariable(const DIGlobalVariable & N)1085 void Verifier::visitDIGlobalVariable(const DIGlobalVariable &N) {
1086   // Checks common to all variables.
1087   visitDIVariable(N);
1088 
1089   AssertDI(N.getTag() == dwarf::DW_TAG_variable, "invalid tag", &N);
1090   AssertDI(!N.getName().empty(), "missing global variable name", &N);
1091   if (auto *V = N.getRawVariable()) {
1092     AssertDI(isa<ConstantAsMetadata>(V) &&
1093                  !isa<Function>(cast<ConstantAsMetadata>(V)->getValue()),
1094              "invalid global varaible ref", &N, V);
1095     visitConstantExprsRecursively(cast<ConstantAsMetadata>(V)->getValue());
1096   }
1097   if (auto *Member = N.getRawStaticDataMemberDeclaration()) {
1098     AssertDI(isa<DIDerivedType>(Member),
1099              "invalid static data member declaration", &N, Member);
1100   }
1101 }
1102 
visitDILocalVariable(const DILocalVariable & N)1103 void Verifier::visitDILocalVariable(const DILocalVariable &N) {
1104   // Checks common to all variables.
1105   visitDIVariable(N);
1106 
1107   AssertDI(N.getTag() == dwarf::DW_TAG_variable, "invalid tag", &N);
1108   AssertDI(N.getRawScope() && isa<DILocalScope>(N.getRawScope()),
1109            "local variable requires a valid scope", &N, N.getRawScope());
1110 }
1111 
visitDIExpression(const DIExpression & N)1112 void Verifier::visitDIExpression(const DIExpression &N) {
1113   AssertDI(N.isValid(), "invalid expression", &N);
1114 }
1115 
visitDIObjCProperty(const DIObjCProperty & N)1116 void Verifier::visitDIObjCProperty(const DIObjCProperty &N) {
1117   AssertDI(N.getTag() == dwarf::DW_TAG_APPLE_property, "invalid tag", &N);
1118   if (auto *T = N.getRawType())
1119     AssertDI(isType(T), "invalid type ref", &N, T);
1120   if (auto *F = N.getRawFile())
1121     AssertDI(isa<DIFile>(F), "invalid file", &N, F);
1122 }
1123 
visitDIImportedEntity(const DIImportedEntity & N)1124 void Verifier::visitDIImportedEntity(const DIImportedEntity &N) {
1125   AssertDI(N.getTag() == dwarf::DW_TAG_imported_module ||
1126                N.getTag() == dwarf::DW_TAG_imported_declaration,
1127            "invalid tag", &N);
1128   if (auto *S = N.getRawScope())
1129     AssertDI(isa<DIScope>(S), "invalid scope for imported entity", &N, S);
1130   AssertDI(isDINode(N.getRawEntity()), "invalid imported entity", &N,
1131            N.getRawEntity());
1132 }
1133 
visitComdat(const Comdat & C)1134 void Verifier::visitComdat(const Comdat &C) {
1135   // The Module is invalid if the GlobalValue has private linkage.  Entities
1136   // with private linkage don't have entries in the symbol table.
1137   if (const GlobalValue *GV = M->getNamedValue(C.getName()))
1138     Assert(!GV->hasPrivateLinkage(), "comdat global value has private linkage",
1139            GV);
1140 }
1141 
visitModuleIdents(const Module & M)1142 void Verifier::visitModuleIdents(const Module &M) {
1143   const NamedMDNode *Idents = M.getNamedMetadata("llvm.ident");
1144   if (!Idents)
1145     return;
1146 
1147   // llvm.ident takes a list of metadata entry. Each entry has only one string.
1148   // Scan each llvm.ident entry and make sure that this requirement is met.
1149   for (const MDNode *N : Idents->operands()) {
1150     Assert(N->getNumOperands() == 1,
1151            "incorrect number of operands in llvm.ident metadata", N);
1152     Assert(dyn_cast_or_null<MDString>(N->getOperand(0)),
1153            ("invalid value for llvm.ident metadata entry operand"
1154             "(the operand should be a string)"),
1155            N->getOperand(0));
1156   }
1157 }
1158 
visitModuleFlags(const Module & M)1159 void Verifier::visitModuleFlags(const Module &M) {
1160   const NamedMDNode *Flags = M.getModuleFlagsMetadata();
1161   if (!Flags) return;
1162 
1163   // Scan each flag, and track the flags and requirements.
1164   DenseMap<const MDString*, const MDNode*> SeenIDs;
1165   SmallVector<const MDNode*, 16> Requirements;
1166   for (const MDNode *MDN : Flags->operands())
1167     visitModuleFlag(MDN, SeenIDs, Requirements);
1168 
1169   // Validate that the requirements in the module are valid.
1170   for (const MDNode *Requirement : Requirements) {
1171     const MDString *Flag = cast<MDString>(Requirement->getOperand(0));
1172     const Metadata *ReqValue = Requirement->getOperand(1);
1173 
1174     const MDNode *Op = SeenIDs.lookup(Flag);
1175     if (!Op) {
1176       CheckFailed("invalid requirement on flag, flag is not present in module",
1177                   Flag);
1178       continue;
1179     }
1180 
1181     if (Op->getOperand(2) != ReqValue) {
1182       CheckFailed(("invalid requirement on flag, "
1183                    "flag does not have the required value"),
1184                   Flag);
1185       continue;
1186     }
1187   }
1188 }
1189 
1190 void
visitModuleFlag(const MDNode * Op,DenseMap<const MDString *,const MDNode * > & SeenIDs,SmallVectorImpl<const MDNode * > & Requirements)1191 Verifier::visitModuleFlag(const MDNode *Op,
1192                           DenseMap<const MDString *, const MDNode *> &SeenIDs,
1193                           SmallVectorImpl<const MDNode *> &Requirements) {
1194   // Each module flag should have three arguments, the merge behavior (a
1195   // constant int), the flag ID (an MDString), and the value.
1196   Assert(Op->getNumOperands() == 3,
1197          "incorrect number of operands in module flag", Op);
1198   Module::ModFlagBehavior MFB;
1199   if (!Module::isValidModFlagBehavior(Op->getOperand(0), MFB)) {
1200     Assert(
1201         mdconst::dyn_extract_or_null<ConstantInt>(Op->getOperand(0)),
1202         "invalid behavior operand in module flag (expected constant integer)",
1203         Op->getOperand(0));
1204     Assert(false,
1205            "invalid behavior operand in module flag (unexpected constant)",
1206            Op->getOperand(0));
1207   }
1208   MDString *ID = dyn_cast_or_null<MDString>(Op->getOperand(1));
1209   Assert(ID, "invalid ID operand in module flag (expected metadata string)",
1210          Op->getOperand(1));
1211 
1212   // Sanity check the values for behaviors with additional requirements.
1213   switch (MFB) {
1214   case Module::Error:
1215   case Module::Warning:
1216   case Module::Override:
1217     // These behavior types accept any value.
1218     break;
1219 
1220   case Module::Require: {
1221     // The value should itself be an MDNode with two operands, a flag ID (an
1222     // MDString), and a value.
1223     MDNode *Value = dyn_cast<MDNode>(Op->getOperand(2));
1224     Assert(Value && Value->getNumOperands() == 2,
1225            "invalid value for 'require' module flag (expected metadata pair)",
1226            Op->getOperand(2));
1227     Assert(isa<MDString>(Value->getOperand(0)),
1228            ("invalid value for 'require' module flag "
1229             "(first value operand should be a string)"),
1230            Value->getOperand(0));
1231 
1232     // Append it to the list of requirements, to check once all module flags are
1233     // scanned.
1234     Requirements.push_back(Value);
1235     break;
1236   }
1237 
1238   case Module::Append:
1239   case Module::AppendUnique: {
1240     // These behavior types require the operand be an MDNode.
1241     Assert(isa<MDNode>(Op->getOperand(2)),
1242            "invalid value for 'append'-type module flag "
1243            "(expected a metadata node)",
1244            Op->getOperand(2));
1245     break;
1246   }
1247   }
1248 
1249   // Unless this is a "requires" flag, check the ID is unique.
1250   if (MFB != Module::Require) {
1251     bool Inserted = SeenIDs.insert(std::make_pair(ID, Op)).second;
1252     Assert(Inserted,
1253            "module flag identifiers must be unique (or of 'require' type)", ID);
1254   }
1255 }
1256 
verifyAttributeTypes(AttributeSet Attrs,unsigned Idx,bool isFunction,const Value * V)1257 void Verifier::verifyAttributeTypes(AttributeSet Attrs, unsigned Idx,
1258                                     bool isFunction, const Value *V) {
1259   unsigned Slot = ~0U;
1260   for (unsigned I = 0, E = Attrs.getNumSlots(); I != E; ++I)
1261     if (Attrs.getSlotIndex(I) == Idx) {
1262       Slot = I;
1263       break;
1264     }
1265 
1266   assert(Slot != ~0U && "Attribute set inconsistency!");
1267 
1268   for (AttributeSet::iterator I = Attrs.begin(Slot), E = Attrs.end(Slot);
1269          I != E; ++I) {
1270     if (I->isStringAttribute())
1271       continue;
1272 
1273     if (I->getKindAsEnum() == Attribute::NoReturn ||
1274         I->getKindAsEnum() == Attribute::NoUnwind ||
1275         I->getKindAsEnum() == Attribute::NoInline ||
1276         I->getKindAsEnum() == Attribute::AlwaysInline ||
1277         I->getKindAsEnum() == Attribute::OptimizeForSize ||
1278         I->getKindAsEnum() == Attribute::StackProtect ||
1279         I->getKindAsEnum() == Attribute::StackProtectReq ||
1280         I->getKindAsEnum() == Attribute::StackProtectStrong ||
1281         I->getKindAsEnum() == Attribute::SafeStack ||
1282         I->getKindAsEnum() == Attribute::NoRedZone ||
1283         I->getKindAsEnum() == Attribute::NoImplicitFloat ||
1284         I->getKindAsEnum() == Attribute::Naked ||
1285         I->getKindAsEnum() == Attribute::InlineHint ||
1286         I->getKindAsEnum() == Attribute::StackAlignment ||
1287         I->getKindAsEnum() == Attribute::UWTable ||
1288         I->getKindAsEnum() == Attribute::NonLazyBind ||
1289         I->getKindAsEnum() == Attribute::ReturnsTwice ||
1290         I->getKindAsEnum() == Attribute::SanitizeAddress ||
1291         I->getKindAsEnum() == Attribute::SanitizeThread ||
1292         I->getKindAsEnum() == Attribute::SanitizeMemory ||
1293         I->getKindAsEnum() == Attribute::MinSize ||
1294         I->getKindAsEnum() == Attribute::NoDuplicate ||
1295         I->getKindAsEnum() == Attribute::Builtin ||
1296         I->getKindAsEnum() == Attribute::NoBuiltin ||
1297         I->getKindAsEnum() == Attribute::Cold ||
1298         I->getKindAsEnum() == Attribute::OptimizeNone ||
1299         I->getKindAsEnum() == Attribute::JumpTable ||
1300         I->getKindAsEnum() == Attribute::Convergent ||
1301         I->getKindAsEnum() == Attribute::ArgMemOnly ||
1302         I->getKindAsEnum() == Attribute::NoRecurse ||
1303         I->getKindAsEnum() == Attribute::InaccessibleMemOnly ||
1304         I->getKindAsEnum() == Attribute::InaccessibleMemOrArgMemOnly ||
1305         I->getKindAsEnum() == Attribute::AllocSize) {
1306       if (!isFunction) {
1307         CheckFailed("Attribute '" + I->getAsString() +
1308                     "' only applies to functions!", V);
1309         return;
1310       }
1311     } else if (I->getKindAsEnum() == Attribute::ReadOnly ||
1312                I->getKindAsEnum() == Attribute::WriteOnly ||
1313                I->getKindAsEnum() == Attribute::ReadNone) {
1314       if (Idx == 0) {
1315         CheckFailed("Attribute '" + I->getAsString() +
1316                     "' does not apply to function returns");
1317         return;
1318       }
1319     } else if (isFunction) {
1320       CheckFailed("Attribute '" + I->getAsString() +
1321                   "' does not apply to functions!", V);
1322       return;
1323     }
1324   }
1325 }
1326 
1327 // VerifyParameterAttrs - Check the given attributes for an argument or return
1328 // value of the specified type.  The value V is printed in error messages.
verifyParameterAttrs(AttributeSet Attrs,unsigned Idx,Type * Ty,bool isReturnValue,const Value * V)1329 void Verifier::verifyParameterAttrs(AttributeSet Attrs, unsigned Idx, Type *Ty,
1330                                     bool isReturnValue, const Value *V) {
1331   if (!Attrs.hasAttributes(Idx))
1332     return;
1333 
1334   verifyAttributeTypes(Attrs, Idx, false, V);
1335 
1336   if (isReturnValue)
1337     Assert(!Attrs.hasAttribute(Idx, Attribute::ByVal) &&
1338                !Attrs.hasAttribute(Idx, Attribute::Nest) &&
1339                !Attrs.hasAttribute(Idx, Attribute::StructRet) &&
1340                !Attrs.hasAttribute(Idx, Attribute::NoCapture) &&
1341                !Attrs.hasAttribute(Idx, Attribute::Returned) &&
1342                !Attrs.hasAttribute(Idx, Attribute::InAlloca) &&
1343                !Attrs.hasAttribute(Idx, Attribute::SwiftSelf) &&
1344                !Attrs.hasAttribute(Idx, Attribute::SwiftError),
1345            "Attributes 'byval', 'inalloca', 'nest', 'sret', 'nocapture', "
1346            "'returned', 'swiftself', and 'swifterror' do not apply to return "
1347            "values!",
1348            V);
1349 
1350   // Check for mutually incompatible attributes.  Only inreg is compatible with
1351   // sret.
1352   unsigned AttrCount = 0;
1353   AttrCount += Attrs.hasAttribute(Idx, Attribute::ByVal);
1354   AttrCount += Attrs.hasAttribute(Idx, Attribute::InAlloca);
1355   AttrCount += Attrs.hasAttribute(Idx, Attribute::StructRet) ||
1356                Attrs.hasAttribute(Idx, Attribute::InReg);
1357   AttrCount += Attrs.hasAttribute(Idx, Attribute::Nest);
1358   Assert(AttrCount <= 1, "Attributes 'byval', 'inalloca', 'inreg', 'nest', "
1359                          "and 'sret' are incompatible!",
1360          V);
1361 
1362   Assert(!(Attrs.hasAttribute(Idx, Attribute::InAlloca) &&
1363            Attrs.hasAttribute(Idx, Attribute::ReadOnly)),
1364          "Attributes "
1365          "'inalloca and readonly' are incompatible!",
1366          V);
1367 
1368   Assert(!(Attrs.hasAttribute(Idx, Attribute::StructRet) &&
1369            Attrs.hasAttribute(Idx, Attribute::Returned)),
1370          "Attributes "
1371          "'sret and returned' are incompatible!",
1372          V);
1373 
1374   Assert(!(Attrs.hasAttribute(Idx, Attribute::ZExt) &&
1375            Attrs.hasAttribute(Idx, Attribute::SExt)),
1376          "Attributes "
1377          "'zeroext and signext' are incompatible!",
1378          V);
1379 
1380   Assert(!(Attrs.hasAttribute(Idx, Attribute::ReadNone) &&
1381            Attrs.hasAttribute(Idx, Attribute::ReadOnly)),
1382          "Attributes "
1383          "'readnone and readonly' are incompatible!",
1384          V);
1385 
1386   Assert(!(Attrs.hasAttribute(Idx, Attribute::ReadNone) &&
1387            Attrs.hasAttribute(Idx, Attribute::WriteOnly)),
1388          "Attributes "
1389          "'readnone and writeonly' are incompatible!",
1390          V);
1391 
1392   Assert(!(Attrs.hasAttribute(Idx, Attribute::ReadOnly) &&
1393            Attrs.hasAttribute(Idx, Attribute::WriteOnly)),
1394          "Attributes "
1395          "'readonly and writeonly' are incompatible!",
1396          V);
1397 
1398   Assert(!(Attrs.hasAttribute(Idx, Attribute::NoInline) &&
1399            Attrs.hasAttribute(Idx, Attribute::AlwaysInline)),
1400          "Attributes "
1401          "'noinline and alwaysinline' are incompatible!",
1402          V);
1403 
1404   Assert(!AttrBuilder(Attrs, Idx)
1405               .overlaps(AttributeFuncs::typeIncompatible(Ty)),
1406          "Wrong types for attribute: " +
1407          AttributeSet::get(*Context, Idx,
1408                         AttributeFuncs::typeIncompatible(Ty)).getAsString(Idx),
1409          V);
1410 
1411   if (PointerType *PTy = dyn_cast<PointerType>(Ty)) {
1412     SmallPtrSet<Type*, 4> Visited;
1413     if (!PTy->getElementType()->isSized(&Visited)) {
1414       Assert(!Attrs.hasAttribute(Idx, Attribute::ByVal) &&
1415                  !Attrs.hasAttribute(Idx, Attribute::InAlloca),
1416              "Attributes 'byval' and 'inalloca' do not support unsized types!",
1417              V);
1418     }
1419     if (!isa<PointerType>(PTy->getElementType()))
1420       Assert(!Attrs.hasAttribute(Idx, Attribute::SwiftError),
1421              "Attribute 'swifterror' only applies to parameters "
1422              "with pointer to pointer type!",
1423              V);
1424   } else {
1425     Assert(!Attrs.hasAttribute(Idx, Attribute::ByVal),
1426            "Attribute 'byval' only applies to parameters with pointer type!",
1427            V);
1428     Assert(!Attrs.hasAttribute(Idx, Attribute::SwiftError),
1429            "Attribute 'swifterror' only applies to parameters "
1430            "with pointer type!",
1431            V);
1432   }
1433 }
1434 
1435 // Check parameter attributes against a function type.
1436 // The value V is printed in error messages.
verifyFunctionAttrs(FunctionType * FT,AttributeSet Attrs,const Value * V)1437 void Verifier::verifyFunctionAttrs(FunctionType *FT, AttributeSet Attrs,
1438                                    const Value *V) {
1439   if (Attrs.isEmpty())
1440     return;
1441 
1442   bool SawNest = false;
1443   bool SawReturned = false;
1444   bool SawSRet = false;
1445   bool SawSwiftSelf = false;
1446   bool SawSwiftError = false;
1447 
1448   for (unsigned i = 0, e = Attrs.getNumSlots(); i != e; ++i) {
1449     unsigned Idx = Attrs.getSlotIndex(i);
1450 
1451     Type *Ty;
1452     if (Idx == 0)
1453       Ty = FT->getReturnType();
1454     else if (Idx-1 < FT->getNumParams())
1455       Ty = FT->getParamType(Idx-1);
1456     else
1457       break;  // VarArgs attributes, verified elsewhere.
1458 
1459     verifyParameterAttrs(Attrs, Idx, Ty, Idx == 0, V);
1460 
1461     if (Idx == 0)
1462       continue;
1463 
1464     if (Attrs.hasAttribute(Idx, Attribute::Nest)) {
1465       Assert(!SawNest, "More than one parameter has attribute nest!", V);
1466       SawNest = true;
1467     }
1468 
1469     if (Attrs.hasAttribute(Idx, Attribute::Returned)) {
1470       Assert(!SawReturned, "More than one parameter has attribute returned!",
1471              V);
1472       Assert(Ty->canLosslesslyBitCastTo(FT->getReturnType()),
1473              "Incompatible "
1474              "argument and return types for 'returned' attribute",
1475              V);
1476       SawReturned = true;
1477     }
1478 
1479     if (Attrs.hasAttribute(Idx, Attribute::StructRet)) {
1480       Assert(!SawSRet, "Cannot have multiple 'sret' parameters!", V);
1481       Assert(Idx == 1 || Idx == 2,
1482              "Attribute 'sret' is not on first or second parameter!", V);
1483       SawSRet = true;
1484     }
1485 
1486     if (Attrs.hasAttribute(Idx, Attribute::SwiftSelf)) {
1487       Assert(!SawSwiftSelf, "Cannot have multiple 'swiftself' parameters!", V);
1488       SawSwiftSelf = true;
1489     }
1490 
1491     if (Attrs.hasAttribute(Idx, Attribute::SwiftError)) {
1492       Assert(!SawSwiftError, "Cannot have multiple 'swifterror' parameters!",
1493              V);
1494       SawSwiftError = true;
1495     }
1496 
1497     if (Attrs.hasAttribute(Idx, Attribute::InAlloca)) {
1498       Assert(Idx == FT->getNumParams(), "inalloca isn't on the last parameter!",
1499              V);
1500     }
1501   }
1502 
1503   if (!Attrs.hasAttributes(AttributeSet::FunctionIndex))
1504     return;
1505 
1506   verifyAttributeTypes(Attrs, AttributeSet::FunctionIndex, true, V);
1507 
1508   Assert(
1509       !(Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::ReadNone) &&
1510         Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::ReadOnly)),
1511       "Attributes 'readnone and readonly' are incompatible!", V);
1512 
1513   Assert(
1514       !(Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::ReadNone) &&
1515         Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::WriteOnly)),
1516       "Attributes 'readnone and writeonly' are incompatible!", V);
1517 
1518   Assert(
1519       !(Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::ReadOnly) &&
1520         Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::WriteOnly)),
1521       "Attributes 'readonly and writeonly' are incompatible!", V);
1522 
1523   Assert(
1524       !(Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::ReadNone) &&
1525         Attrs.hasAttribute(AttributeSet::FunctionIndex,
1526                            Attribute::InaccessibleMemOrArgMemOnly)),
1527       "Attributes 'readnone and inaccessiblemem_or_argmemonly' are incompatible!", V);
1528 
1529   Assert(
1530       !(Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::ReadNone) &&
1531         Attrs.hasAttribute(AttributeSet::FunctionIndex,
1532                            Attribute::InaccessibleMemOnly)),
1533       "Attributes 'readnone and inaccessiblememonly' are incompatible!", V);
1534 
1535   Assert(
1536       !(Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::NoInline) &&
1537         Attrs.hasAttribute(AttributeSet::FunctionIndex,
1538                            Attribute::AlwaysInline)),
1539       "Attributes 'noinline and alwaysinline' are incompatible!", V);
1540 
1541   if (Attrs.hasAttribute(AttributeSet::FunctionIndex,
1542                          Attribute::OptimizeNone)) {
1543     Assert(Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::NoInline),
1544            "Attribute 'optnone' requires 'noinline'!", V);
1545 
1546     Assert(!Attrs.hasAttribute(AttributeSet::FunctionIndex,
1547                                Attribute::OptimizeForSize),
1548            "Attributes 'optsize and optnone' are incompatible!", V);
1549 
1550     Assert(!Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::MinSize),
1551            "Attributes 'minsize and optnone' are incompatible!", V);
1552   }
1553 
1554   if (Attrs.hasAttribute(AttributeSet::FunctionIndex,
1555                          Attribute::JumpTable)) {
1556     const GlobalValue *GV = cast<GlobalValue>(V);
1557     Assert(GV->hasGlobalUnnamedAddr(),
1558            "Attribute 'jumptable' requires 'unnamed_addr'", V);
1559   }
1560 
1561   if (Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::AllocSize)) {
1562     std::pair<unsigned, Optional<unsigned>> Args =
1563         Attrs.getAllocSizeArgs(AttributeSet::FunctionIndex);
1564 
1565     auto CheckParam = [&](StringRef Name, unsigned ParamNo) {
1566       if (ParamNo >= FT->getNumParams()) {
1567         CheckFailed("'allocsize' " + Name + " argument is out of bounds", V);
1568         return false;
1569       }
1570 
1571       if (!FT->getParamType(ParamNo)->isIntegerTy()) {
1572         CheckFailed("'allocsize' " + Name +
1573                         " argument must refer to an integer parameter",
1574                     V);
1575         return false;
1576       }
1577 
1578       return true;
1579     };
1580 
1581     if (!CheckParam("element size", Args.first))
1582       return;
1583 
1584     if (Args.second && !CheckParam("number of elements", *Args.second))
1585       return;
1586   }
1587 }
1588 
verifyFunctionMetadata(ArrayRef<std::pair<unsigned,MDNode * >> MDs)1589 void Verifier::verifyFunctionMetadata(
1590     ArrayRef<std::pair<unsigned, MDNode *>> MDs) {
1591   for (const auto &Pair : MDs) {
1592     if (Pair.first == LLVMContext::MD_prof) {
1593       MDNode *MD = Pair.second;
1594       Assert(MD->getNumOperands() == 2,
1595              "!prof annotations should have exactly 2 operands", MD);
1596 
1597       // Check first operand.
1598       Assert(MD->getOperand(0) != nullptr, "first operand should not be null",
1599              MD);
1600       Assert(isa<MDString>(MD->getOperand(0)),
1601              "expected string with name of the !prof annotation", MD);
1602       MDString *MDS = cast<MDString>(MD->getOperand(0));
1603       StringRef ProfName = MDS->getString();
1604       Assert(ProfName.equals("function_entry_count"),
1605              "first operand should be 'function_entry_count'", MD);
1606 
1607       // Check second operand.
1608       Assert(MD->getOperand(1) != nullptr, "second operand should not be null",
1609              MD);
1610       Assert(isa<ConstantAsMetadata>(MD->getOperand(1)),
1611              "expected integer argument to function_entry_count", MD);
1612     }
1613   }
1614 }
1615 
visitConstantExprsRecursively(const Constant * EntryC)1616 void Verifier::visitConstantExprsRecursively(const Constant *EntryC) {
1617   if (!ConstantExprVisited.insert(EntryC).second)
1618     return;
1619 
1620   SmallVector<const Constant *, 16> Stack;
1621   Stack.push_back(EntryC);
1622 
1623   while (!Stack.empty()) {
1624     const Constant *C = Stack.pop_back_val();
1625 
1626     // Check this constant expression.
1627     if (const auto *CE = dyn_cast<ConstantExpr>(C))
1628       visitConstantExpr(CE);
1629 
1630     if (const auto *GV = dyn_cast<GlobalValue>(C)) {
1631       // Global Values get visited separately, but we do need to make sure
1632       // that the global value is in the correct module
1633       Assert(GV->getParent() == M, "Referencing global in another module!",
1634              EntryC, M, GV, GV->getParent());
1635       continue;
1636     }
1637 
1638     // Visit all sub-expressions.
1639     for (const Use &U : C->operands()) {
1640       const auto *OpC = dyn_cast<Constant>(U);
1641       if (!OpC)
1642         continue;
1643       if (!ConstantExprVisited.insert(OpC).second)
1644         continue;
1645       Stack.push_back(OpC);
1646     }
1647   }
1648 }
1649 
visitConstantExpr(const ConstantExpr * CE)1650 void Verifier::visitConstantExpr(const ConstantExpr *CE) {
1651   if (CE->getOpcode() != Instruction::BitCast)
1652     return;
1653 
1654   Assert(CastInst::castIsValid(Instruction::BitCast, CE->getOperand(0),
1655                                CE->getType()),
1656          "Invalid bitcast", CE);
1657 }
1658 
verifyAttributeCount(AttributeSet Attrs,unsigned Params)1659 bool Verifier::verifyAttributeCount(AttributeSet Attrs, unsigned Params) {
1660   if (Attrs.getNumSlots() == 0)
1661     return true;
1662 
1663   unsigned LastSlot = Attrs.getNumSlots() - 1;
1664   unsigned LastIndex = Attrs.getSlotIndex(LastSlot);
1665   if (LastIndex <= Params
1666       || (LastIndex == AttributeSet::FunctionIndex
1667           && (LastSlot == 0 || Attrs.getSlotIndex(LastSlot - 1) <= Params)))
1668     return true;
1669 
1670   return false;
1671 }
1672 
1673 /// Verify that statepoint intrinsic is well formed.
verifyStatepoint(ImmutableCallSite CS)1674 void Verifier::verifyStatepoint(ImmutableCallSite CS) {
1675   assert(CS.getCalledFunction() &&
1676          CS.getCalledFunction()->getIntrinsicID() ==
1677            Intrinsic::experimental_gc_statepoint);
1678 
1679   const Instruction &CI = *CS.getInstruction();
1680 
1681   Assert(!CS.doesNotAccessMemory() && !CS.onlyReadsMemory() &&
1682          !CS.onlyAccessesArgMemory(),
1683          "gc.statepoint must read and write all memory to preserve "
1684          "reordering restrictions required by safepoint semantics",
1685          &CI);
1686 
1687   const Value *IDV = CS.getArgument(0);
1688   Assert(isa<ConstantInt>(IDV), "gc.statepoint ID must be a constant integer",
1689          &CI);
1690 
1691   const Value *NumPatchBytesV = CS.getArgument(1);
1692   Assert(isa<ConstantInt>(NumPatchBytesV),
1693          "gc.statepoint number of patchable bytes must be a constant integer",
1694          &CI);
1695   const int64_t NumPatchBytes =
1696       cast<ConstantInt>(NumPatchBytesV)->getSExtValue();
1697   assert(isInt<32>(NumPatchBytes) && "NumPatchBytesV is an i32!");
1698   Assert(NumPatchBytes >= 0, "gc.statepoint number of patchable bytes must be "
1699                              "positive",
1700          &CI);
1701 
1702   const Value *Target = CS.getArgument(2);
1703   auto *PT = dyn_cast<PointerType>(Target->getType());
1704   Assert(PT && PT->getElementType()->isFunctionTy(),
1705          "gc.statepoint callee must be of function pointer type", &CI, Target);
1706   FunctionType *TargetFuncType = cast<FunctionType>(PT->getElementType());
1707 
1708   const Value *NumCallArgsV = CS.getArgument(3);
1709   Assert(isa<ConstantInt>(NumCallArgsV),
1710          "gc.statepoint number of arguments to underlying call "
1711          "must be constant integer",
1712          &CI);
1713   const int NumCallArgs = cast<ConstantInt>(NumCallArgsV)->getZExtValue();
1714   Assert(NumCallArgs >= 0,
1715          "gc.statepoint number of arguments to underlying call "
1716          "must be positive",
1717          &CI);
1718   const int NumParams = (int)TargetFuncType->getNumParams();
1719   if (TargetFuncType->isVarArg()) {
1720     Assert(NumCallArgs >= NumParams,
1721            "gc.statepoint mismatch in number of vararg call args", &CI);
1722 
1723     // TODO: Remove this limitation
1724     Assert(TargetFuncType->getReturnType()->isVoidTy(),
1725            "gc.statepoint doesn't support wrapping non-void "
1726            "vararg functions yet",
1727            &CI);
1728   } else
1729     Assert(NumCallArgs == NumParams,
1730            "gc.statepoint mismatch in number of call args", &CI);
1731 
1732   const Value *FlagsV = CS.getArgument(4);
1733   Assert(isa<ConstantInt>(FlagsV),
1734          "gc.statepoint flags must be constant integer", &CI);
1735   const uint64_t Flags = cast<ConstantInt>(FlagsV)->getZExtValue();
1736   Assert((Flags & ~(uint64_t)StatepointFlags::MaskAll) == 0,
1737          "unknown flag used in gc.statepoint flags argument", &CI);
1738 
1739   // Verify that the types of the call parameter arguments match
1740   // the type of the wrapped callee.
1741   for (int i = 0; i < NumParams; i++) {
1742     Type *ParamType = TargetFuncType->getParamType(i);
1743     Type *ArgType = CS.getArgument(5 + i)->getType();
1744     Assert(ArgType == ParamType,
1745            "gc.statepoint call argument does not match wrapped "
1746            "function type",
1747            &CI);
1748   }
1749 
1750   const int EndCallArgsInx = 4 + NumCallArgs;
1751 
1752   const Value *NumTransitionArgsV = CS.getArgument(EndCallArgsInx+1);
1753   Assert(isa<ConstantInt>(NumTransitionArgsV),
1754          "gc.statepoint number of transition arguments "
1755          "must be constant integer",
1756          &CI);
1757   const int NumTransitionArgs =
1758       cast<ConstantInt>(NumTransitionArgsV)->getZExtValue();
1759   Assert(NumTransitionArgs >= 0,
1760          "gc.statepoint number of transition arguments must be positive", &CI);
1761   const int EndTransitionArgsInx = EndCallArgsInx + 1 + NumTransitionArgs;
1762 
1763   const Value *NumDeoptArgsV = CS.getArgument(EndTransitionArgsInx+1);
1764   Assert(isa<ConstantInt>(NumDeoptArgsV),
1765          "gc.statepoint number of deoptimization arguments "
1766          "must be constant integer",
1767          &CI);
1768   const int NumDeoptArgs = cast<ConstantInt>(NumDeoptArgsV)->getZExtValue();
1769   Assert(NumDeoptArgs >= 0, "gc.statepoint number of deoptimization arguments "
1770                             "must be positive",
1771          &CI);
1772 
1773   const int ExpectedNumArgs =
1774       7 + NumCallArgs + NumTransitionArgs + NumDeoptArgs;
1775   Assert(ExpectedNumArgs <= (int)CS.arg_size(),
1776          "gc.statepoint too few arguments according to length fields", &CI);
1777 
1778   // Check that the only uses of this gc.statepoint are gc.result or
1779   // gc.relocate calls which are tied to this statepoint and thus part
1780   // of the same statepoint sequence
1781   for (const User *U : CI.users()) {
1782     const CallInst *Call = dyn_cast<const CallInst>(U);
1783     Assert(Call, "illegal use of statepoint token", &CI, U);
1784     if (!Call) continue;
1785     Assert(isa<GCRelocateInst>(Call) || isa<GCResultInst>(Call),
1786            "gc.result or gc.relocate are the only value uses"
1787            "of a gc.statepoint",
1788            &CI, U);
1789     if (isa<GCResultInst>(Call)) {
1790       Assert(Call->getArgOperand(0) == &CI,
1791              "gc.result connected to wrong gc.statepoint", &CI, Call);
1792     } else if (isa<GCRelocateInst>(Call)) {
1793       Assert(Call->getArgOperand(0) == &CI,
1794              "gc.relocate connected to wrong gc.statepoint", &CI, Call);
1795     }
1796   }
1797 
1798   // Note: It is legal for a single derived pointer to be listed multiple
1799   // times.  It's non-optimal, but it is legal.  It can also happen after
1800   // insertion if we strip a bitcast away.
1801   // Note: It is really tempting to check that each base is relocated and
1802   // that a derived pointer is never reused as a base pointer.  This turns
1803   // out to be problematic since optimizations run after safepoint insertion
1804   // can recognize equality properties that the insertion logic doesn't know
1805   // about.  See example statepoint.ll in the verifier subdirectory
1806 }
1807 
verifyFrameRecoverIndices()1808 void Verifier::verifyFrameRecoverIndices() {
1809   for (auto &Counts : FrameEscapeInfo) {
1810     Function *F = Counts.first;
1811     unsigned EscapedObjectCount = Counts.second.first;
1812     unsigned MaxRecoveredIndex = Counts.second.second;
1813     Assert(MaxRecoveredIndex <= EscapedObjectCount,
1814            "all indices passed to llvm.localrecover must be less than the "
1815            "number of arguments passed ot llvm.localescape in the parent "
1816            "function",
1817            F);
1818   }
1819 }
1820 
getSuccPad(TerminatorInst * Terminator)1821 static Instruction *getSuccPad(TerminatorInst *Terminator) {
1822   BasicBlock *UnwindDest;
1823   if (auto *II = dyn_cast<InvokeInst>(Terminator))
1824     UnwindDest = II->getUnwindDest();
1825   else if (auto *CSI = dyn_cast<CatchSwitchInst>(Terminator))
1826     UnwindDest = CSI->getUnwindDest();
1827   else
1828     UnwindDest = cast<CleanupReturnInst>(Terminator)->getUnwindDest();
1829   return UnwindDest->getFirstNonPHI();
1830 }
1831 
verifySiblingFuncletUnwinds()1832 void Verifier::verifySiblingFuncletUnwinds() {
1833   SmallPtrSet<Instruction *, 8> Visited;
1834   SmallPtrSet<Instruction *, 8> Active;
1835   for (const auto &Pair : SiblingFuncletInfo) {
1836     Instruction *PredPad = Pair.first;
1837     if (Visited.count(PredPad))
1838       continue;
1839     Active.insert(PredPad);
1840     TerminatorInst *Terminator = Pair.second;
1841     do {
1842       Instruction *SuccPad = getSuccPad(Terminator);
1843       if (Active.count(SuccPad)) {
1844         // Found a cycle; report error
1845         Instruction *CyclePad = SuccPad;
1846         SmallVector<Instruction *, 8> CycleNodes;
1847         do {
1848           CycleNodes.push_back(CyclePad);
1849           TerminatorInst *CycleTerminator = SiblingFuncletInfo[CyclePad];
1850           if (CycleTerminator != CyclePad)
1851             CycleNodes.push_back(CycleTerminator);
1852           CyclePad = getSuccPad(CycleTerminator);
1853         } while (CyclePad != SuccPad);
1854         Assert(false, "EH pads can't handle each other's exceptions",
1855                ArrayRef<Instruction *>(CycleNodes));
1856       }
1857       // Don't re-walk a node we've already checked
1858       if (!Visited.insert(SuccPad).second)
1859         break;
1860       // Walk to this successor if it has a map entry.
1861       PredPad = SuccPad;
1862       auto TermI = SiblingFuncletInfo.find(PredPad);
1863       if (TermI == SiblingFuncletInfo.end())
1864         break;
1865       Terminator = TermI->second;
1866       Active.insert(PredPad);
1867     } while (true);
1868     // Each node only has one successor, so we've walked all the active
1869     // nodes' successors.
1870     Active.clear();
1871   }
1872 }
1873 
1874 // visitFunction - Verify that a function is ok.
1875 //
visitFunction(const Function & F)1876 void Verifier::visitFunction(const Function &F) {
1877   visitGlobalValue(F);
1878 
1879   // Check function arguments.
1880   FunctionType *FT = F.getFunctionType();
1881   unsigned NumArgs = F.arg_size();
1882 
1883   Assert(Context == &F.getContext(),
1884          "Function context does not match Module context!", &F);
1885 
1886   Assert(!F.hasCommonLinkage(), "Functions may not have common linkage", &F);
1887   Assert(FT->getNumParams() == NumArgs,
1888          "# formal arguments must match # of arguments for function type!", &F,
1889          FT);
1890   Assert(F.getReturnType()->isFirstClassType() ||
1891              F.getReturnType()->isVoidTy() || F.getReturnType()->isStructTy(),
1892          "Functions cannot return aggregate values!", &F);
1893 
1894   Assert(!F.hasStructRetAttr() || F.getReturnType()->isVoidTy(),
1895          "Invalid struct return type!", &F);
1896 
1897   AttributeSet Attrs = F.getAttributes();
1898 
1899   Assert(verifyAttributeCount(Attrs, FT->getNumParams()),
1900          "Attribute after last parameter!", &F);
1901 
1902   // Check function attributes.
1903   verifyFunctionAttrs(FT, Attrs, &F);
1904 
1905   // On function declarations/definitions, we do not support the builtin
1906   // attribute. We do not check this in VerifyFunctionAttrs since that is
1907   // checking for Attributes that can/can not ever be on functions.
1908   Assert(!Attrs.hasAttribute(AttributeSet::FunctionIndex, Attribute::Builtin),
1909          "Attribute 'builtin' can only be applied to a callsite.", &F);
1910 
1911   // Check that this function meets the restrictions on this calling convention.
1912   // Sometimes varargs is used for perfectly forwarding thunks, so some of these
1913   // restrictions can be lifted.
1914   switch (F.getCallingConv()) {
1915   default:
1916   case CallingConv::C:
1917     break;
1918   case CallingConv::Fast:
1919   case CallingConv::Cold:
1920   case CallingConv::Intel_OCL_BI:
1921   case CallingConv::PTX_Kernel:
1922   case CallingConv::PTX_Device:
1923     Assert(!F.isVarArg(), "Calling convention does not support varargs or "
1924                           "perfect forwarding!",
1925            &F);
1926     break;
1927   }
1928 
1929   bool isLLVMdotName = F.getName().size() >= 5 &&
1930                        F.getName().substr(0, 5) == "llvm.";
1931 
1932   // Check that the argument values match the function type for this function...
1933   unsigned i = 0;
1934   for (const Argument &Arg : F.args()) {
1935     Assert(Arg.getType() == FT->getParamType(i),
1936            "Argument value does not match function argument type!", &Arg,
1937            FT->getParamType(i));
1938     Assert(Arg.getType()->isFirstClassType(),
1939            "Function arguments must have first-class types!", &Arg);
1940     if (!isLLVMdotName) {
1941       Assert(!Arg.getType()->isMetadataTy(),
1942              "Function takes metadata but isn't an intrinsic", &Arg, &F);
1943       Assert(!Arg.getType()->isTokenTy(),
1944              "Function takes token but isn't an intrinsic", &Arg, &F);
1945     }
1946 
1947     // Check that swifterror argument is only used by loads and stores.
1948     if (Attrs.hasAttribute(i+1, Attribute::SwiftError)) {
1949       verifySwiftErrorValue(&Arg);
1950     }
1951     ++i;
1952   }
1953 
1954   if (!isLLVMdotName)
1955     Assert(!F.getReturnType()->isTokenTy(),
1956            "Functions returns a token but isn't an intrinsic", &F);
1957 
1958   // Get the function metadata attachments.
1959   SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
1960   F.getAllMetadata(MDs);
1961   assert(F.hasMetadata() != MDs.empty() && "Bit out-of-sync");
1962   verifyFunctionMetadata(MDs);
1963 
1964   // Check validity of the personality function
1965   if (F.hasPersonalityFn()) {
1966     auto *Per = dyn_cast<Function>(F.getPersonalityFn()->stripPointerCasts());
1967     if (Per)
1968       Assert(Per->getParent() == F.getParent(),
1969              "Referencing personality function in another module!",
1970              &F, F.getParent(), Per, Per->getParent());
1971   }
1972 
1973   if (F.isMaterializable()) {
1974     // Function has a body somewhere we can't see.
1975     Assert(MDs.empty(), "unmaterialized function cannot have metadata", &F,
1976            MDs.empty() ? nullptr : MDs.front().second);
1977   } else if (F.isDeclaration()) {
1978     for (const auto &I : MDs) {
1979       AssertDI(I.first != LLVMContext::MD_dbg,
1980                "function declaration may not have a !dbg attachment", &F);
1981       Assert(I.first != LLVMContext::MD_prof,
1982              "function declaration may not have a !prof attachment", &F);
1983 
1984       // Verify the metadata itself.
1985       visitMDNode(*I.second);
1986     }
1987     Assert(!F.hasPersonalityFn(),
1988            "Function declaration shouldn't have a personality routine", &F);
1989   } else {
1990     // Verify that this function (which has a body) is not named "llvm.*".  It
1991     // is not legal to define intrinsics.
1992     Assert(!isLLVMdotName, "llvm intrinsics cannot be defined!", &F);
1993 
1994     // Check the entry node
1995     const BasicBlock *Entry = &F.getEntryBlock();
1996     Assert(pred_empty(Entry),
1997            "Entry block to function must not have predecessors!", Entry);
1998 
1999     // The address of the entry block cannot be taken, unless it is dead.
2000     if (Entry->hasAddressTaken()) {
2001       Assert(!BlockAddress::lookup(Entry)->isConstantUsed(),
2002              "blockaddress may not be used with the entry block!", Entry);
2003     }
2004 
2005     unsigned NumDebugAttachments = 0, NumProfAttachments = 0;
2006     // Visit metadata attachments.
2007     for (const auto &I : MDs) {
2008       // Verify that the attachment is legal.
2009       switch (I.first) {
2010       default:
2011         break;
2012       case LLVMContext::MD_dbg:
2013         ++NumDebugAttachments;
2014         AssertDI(NumDebugAttachments == 1,
2015                  "function must have a single !dbg attachment", &F, I.second);
2016         AssertDI(isa<DISubprogram>(I.second),
2017                  "function !dbg attachment must be a subprogram", &F, I.second);
2018         break;
2019       case LLVMContext::MD_prof:
2020         ++NumProfAttachments;
2021         Assert(NumProfAttachments == 1,
2022                "function must have a single !prof attachment", &F, I.second);
2023         break;
2024       }
2025 
2026       // Verify the metadata itself.
2027       visitMDNode(*I.second);
2028     }
2029   }
2030 
2031   // If this function is actually an intrinsic, verify that it is only used in
2032   // direct call/invokes, never having its "address taken".
2033   // Only do this if the module is materialized, otherwise we don't have all the
2034   // uses.
2035   if (F.getIntrinsicID() && F.getParent()->isMaterialized()) {
2036     const User *U;
2037     if (F.hasAddressTaken(&U))
2038       Assert(0, "Invalid user of intrinsic instruction!", U);
2039   }
2040 
2041   Assert(!F.hasDLLImportStorageClass() ||
2042              (F.isDeclaration() && F.hasExternalLinkage()) ||
2043              F.hasAvailableExternallyLinkage(),
2044          "Function is marked as dllimport, but not external.", &F);
2045 
2046   auto *N = F.getSubprogram();
2047   if (!N)
2048     return;
2049 
2050   visitDISubprogram(*N);
2051 
2052   // Check that all !dbg attachments lead to back to N (or, at least, another
2053   // subprogram that describes the same function).
2054   //
2055   // FIXME: Check this incrementally while visiting !dbg attachments.
2056   // FIXME: Only check when N is the canonical subprogram for F.
2057   SmallPtrSet<const MDNode *, 32> Seen;
2058   for (auto &BB : F)
2059     for (auto &I : BB) {
2060       // Be careful about using DILocation here since we might be dealing with
2061       // broken code (this is the Verifier after all).
2062       DILocation *DL =
2063           dyn_cast_or_null<DILocation>(I.getDebugLoc().getAsMDNode());
2064       if (!DL)
2065         continue;
2066       if (!Seen.insert(DL).second)
2067         continue;
2068 
2069       DILocalScope *Scope = DL->getInlinedAtScope();
2070       if (Scope && !Seen.insert(Scope).second)
2071         continue;
2072 
2073       DISubprogram *SP = Scope ? Scope->getSubprogram() : nullptr;
2074 
2075       // Scope and SP could be the same MDNode and we don't want to skip
2076       // validation in that case
2077       if (SP && ((Scope != SP) && !Seen.insert(SP).second))
2078         continue;
2079 
2080       // FIXME: Once N is canonical, check "SP == &N".
2081       Assert(SP->describes(&F),
2082              "!dbg attachment points at wrong subprogram for function", N, &F,
2083              &I, DL, Scope, SP);
2084     }
2085 }
2086 
2087 // verifyBasicBlock - Verify that a basic block is well formed...
2088 //
visitBasicBlock(BasicBlock & BB)2089 void Verifier::visitBasicBlock(BasicBlock &BB) {
2090   InstsInThisBlock.clear();
2091 
2092   // Ensure that basic blocks have terminators!
2093   Assert(BB.getTerminator(), "Basic Block does not have terminator!", &BB);
2094 
2095   // Check constraints that this basic block imposes on all of the PHI nodes in
2096   // it.
2097   if (isa<PHINode>(BB.front())) {
2098     SmallVector<BasicBlock*, 8> Preds(pred_begin(&BB), pred_end(&BB));
2099     SmallVector<std::pair<BasicBlock*, Value*>, 8> Values;
2100     std::sort(Preds.begin(), Preds.end());
2101     PHINode *PN;
2102     for (BasicBlock::iterator I = BB.begin(); (PN = dyn_cast<PHINode>(I));++I) {
2103       // Ensure that PHI nodes have at least one entry!
2104       Assert(PN->getNumIncomingValues() != 0,
2105              "PHI nodes must have at least one entry.  If the block is dead, "
2106              "the PHI should be removed!",
2107              PN);
2108       Assert(PN->getNumIncomingValues() == Preds.size(),
2109              "PHINode should have one entry for each predecessor of its "
2110              "parent basic block!",
2111              PN);
2112 
2113       // Get and sort all incoming values in the PHI node...
2114       Values.clear();
2115       Values.reserve(PN->getNumIncomingValues());
2116       for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
2117         Values.push_back(std::make_pair(PN->getIncomingBlock(i),
2118                                         PN->getIncomingValue(i)));
2119       std::sort(Values.begin(), Values.end());
2120 
2121       for (unsigned i = 0, e = Values.size(); i != e; ++i) {
2122         // Check to make sure that if there is more than one entry for a
2123         // particular basic block in this PHI node, that the incoming values are
2124         // all identical.
2125         //
2126         Assert(i == 0 || Values[i].first != Values[i - 1].first ||
2127                    Values[i].second == Values[i - 1].second,
2128                "PHI node has multiple entries for the same basic block with "
2129                "different incoming values!",
2130                PN, Values[i].first, Values[i].second, Values[i - 1].second);
2131 
2132         // Check to make sure that the predecessors and PHI node entries are
2133         // matched up.
2134         Assert(Values[i].first == Preds[i],
2135                "PHI node entries do not match predecessors!", PN,
2136                Values[i].first, Preds[i]);
2137       }
2138     }
2139   }
2140 
2141   // Check that all instructions have their parent pointers set up correctly.
2142   for (auto &I : BB)
2143   {
2144     Assert(I.getParent() == &BB, "Instruction has bogus parent pointer!");
2145   }
2146 }
2147 
visitTerminatorInst(TerminatorInst & I)2148 void Verifier::visitTerminatorInst(TerminatorInst &I) {
2149   // Ensure that terminators only exist at the end of the basic block.
2150   Assert(&I == I.getParent()->getTerminator(),
2151          "Terminator found in the middle of a basic block!", I.getParent());
2152   visitInstruction(I);
2153 }
2154 
visitBranchInst(BranchInst & BI)2155 void Verifier::visitBranchInst(BranchInst &BI) {
2156   if (BI.isConditional()) {
2157     Assert(BI.getCondition()->getType()->isIntegerTy(1),
2158            "Branch condition is not 'i1' type!", &BI, BI.getCondition());
2159   }
2160   visitTerminatorInst(BI);
2161 }
2162 
visitReturnInst(ReturnInst & RI)2163 void Verifier::visitReturnInst(ReturnInst &RI) {
2164   Function *F = RI.getParent()->getParent();
2165   unsigned N = RI.getNumOperands();
2166   if (F->getReturnType()->isVoidTy())
2167     Assert(N == 0,
2168            "Found return instr that returns non-void in Function of void "
2169            "return type!",
2170            &RI, F->getReturnType());
2171   else
2172     Assert(N == 1 && F->getReturnType() == RI.getOperand(0)->getType(),
2173            "Function return type does not match operand "
2174            "type of return inst!",
2175            &RI, F->getReturnType());
2176 
2177   // Check to make sure that the return value has necessary properties for
2178   // terminators...
2179   visitTerminatorInst(RI);
2180 }
2181 
visitSwitchInst(SwitchInst & SI)2182 void Verifier::visitSwitchInst(SwitchInst &SI) {
2183   // Check to make sure that all of the constants in the switch instruction
2184   // have the same type as the switched-on value.
2185   Type *SwitchTy = SI.getCondition()->getType();
2186   SmallPtrSet<ConstantInt*, 32> Constants;
2187   for (auto &Case : SI.cases()) {
2188     Assert(Case.getCaseValue()->getType() == SwitchTy,
2189            "Switch constants must all be same type as switch value!", &SI);
2190     Assert(Constants.insert(Case.getCaseValue()).second,
2191            "Duplicate integer as switch case", &SI, Case.getCaseValue());
2192   }
2193 
2194   visitTerminatorInst(SI);
2195 }
2196 
visitIndirectBrInst(IndirectBrInst & BI)2197 void Verifier::visitIndirectBrInst(IndirectBrInst &BI) {
2198   Assert(BI.getAddress()->getType()->isPointerTy(),
2199          "Indirectbr operand must have pointer type!", &BI);
2200   for (unsigned i = 0, e = BI.getNumDestinations(); i != e; ++i)
2201     Assert(BI.getDestination(i)->getType()->isLabelTy(),
2202            "Indirectbr destinations must all have pointer type!", &BI);
2203 
2204   visitTerminatorInst(BI);
2205 }
2206 
visitSelectInst(SelectInst & SI)2207 void Verifier::visitSelectInst(SelectInst &SI) {
2208   Assert(!SelectInst::areInvalidOperands(SI.getOperand(0), SI.getOperand(1),
2209                                          SI.getOperand(2)),
2210          "Invalid operands for select instruction!", &SI);
2211 
2212   Assert(SI.getTrueValue()->getType() == SI.getType(),
2213          "Select values must have same type as select instruction!", &SI);
2214   visitInstruction(SI);
2215 }
2216 
2217 /// visitUserOp1 - User defined operators shouldn't live beyond the lifetime of
2218 /// a pass, if any exist, it's an error.
2219 ///
visitUserOp1(Instruction & I)2220 void Verifier::visitUserOp1(Instruction &I) {
2221   Assert(0, "User-defined operators should not live outside of a pass!", &I);
2222 }
2223 
visitTruncInst(TruncInst & I)2224 void Verifier::visitTruncInst(TruncInst &I) {
2225   // Get the source and destination types
2226   Type *SrcTy = I.getOperand(0)->getType();
2227   Type *DestTy = I.getType();
2228 
2229   // Get the size of the types in bits, we'll need this later
2230   unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
2231   unsigned DestBitSize = DestTy->getScalarSizeInBits();
2232 
2233   Assert(SrcTy->isIntOrIntVectorTy(), "Trunc only operates on integer", &I);
2234   Assert(DestTy->isIntOrIntVectorTy(), "Trunc only produces integer", &I);
2235   Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(),
2236          "trunc source and destination must both be a vector or neither", &I);
2237   Assert(SrcBitSize > DestBitSize, "DestTy too big for Trunc", &I);
2238 
2239   visitInstruction(I);
2240 }
2241 
visitZExtInst(ZExtInst & I)2242 void Verifier::visitZExtInst(ZExtInst &I) {
2243   // Get the source and destination types
2244   Type *SrcTy = I.getOperand(0)->getType();
2245   Type *DestTy = I.getType();
2246 
2247   // Get the size of the types in bits, we'll need this later
2248   Assert(SrcTy->isIntOrIntVectorTy(), "ZExt only operates on integer", &I);
2249   Assert(DestTy->isIntOrIntVectorTy(), "ZExt only produces an integer", &I);
2250   Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(),
2251          "zext source and destination must both be a vector or neither", &I);
2252   unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
2253   unsigned DestBitSize = DestTy->getScalarSizeInBits();
2254 
2255   Assert(SrcBitSize < DestBitSize, "Type too small for ZExt", &I);
2256 
2257   visitInstruction(I);
2258 }
2259 
visitSExtInst(SExtInst & I)2260 void Verifier::visitSExtInst(SExtInst &I) {
2261   // Get the source and destination types
2262   Type *SrcTy = I.getOperand(0)->getType();
2263   Type *DestTy = I.getType();
2264 
2265   // Get the size of the types in bits, we'll need this later
2266   unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
2267   unsigned DestBitSize = DestTy->getScalarSizeInBits();
2268 
2269   Assert(SrcTy->isIntOrIntVectorTy(), "SExt only operates on integer", &I);
2270   Assert(DestTy->isIntOrIntVectorTy(), "SExt only produces an integer", &I);
2271   Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(),
2272          "sext source and destination must both be a vector or neither", &I);
2273   Assert(SrcBitSize < DestBitSize, "Type too small for SExt", &I);
2274 
2275   visitInstruction(I);
2276 }
2277 
visitFPTruncInst(FPTruncInst & I)2278 void Verifier::visitFPTruncInst(FPTruncInst &I) {
2279   // Get the source and destination types
2280   Type *SrcTy = I.getOperand(0)->getType();
2281   Type *DestTy = I.getType();
2282   // Get the size of the types in bits, we'll need this later
2283   unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
2284   unsigned DestBitSize = DestTy->getScalarSizeInBits();
2285 
2286   Assert(SrcTy->isFPOrFPVectorTy(), "FPTrunc only operates on FP", &I);
2287   Assert(DestTy->isFPOrFPVectorTy(), "FPTrunc only produces an FP", &I);
2288   Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(),
2289          "fptrunc source and destination must both be a vector or neither", &I);
2290   Assert(SrcBitSize > DestBitSize, "DestTy too big for FPTrunc", &I);
2291 
2292   visitInstruction(I);
2293 }
2294 
visitFPExtInst(FPExtInst & I)2295 void Verifier::visitFPExtInst(FPExtInst &I) {
2296   // Get the source and destination types
2297   Type *SrcTy = I.getOperand(0)->getType();
2298   Type *DestTy = I.getType();
2299 
2300   // Get the size of the types in bits, we'll need this later
2301   unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
2302   unsigned DestBitSize = DestTy->getScalarSizeInBits();
2303 
2304   Assert(SrcTy->isFPOrFPVectorTy(), "FPExt only operates on FP", &I);
2305   Assert(DestTy->isFPOrFPVectorTy(), "FPExt only produces an FP", &I);
2306   Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(),
2307          "fpext source and destination must both be a vector or neither", &I);
2308   Assert(SrcBitSize < DestBitSize, "DestTy too small for FPExt", &I);
2309 
2310   visitInstruction(I);
2311 }
2312 
visitUIToFPInst(UIToFPInst & I)2313 void Verifier::visitUIToFPInst(UIToFPInst &I) {
2314   // Get the source and destination types
2315   Type *SrcTy = I.getOperand(0)->getType();
2316   Type *DestTy = I.getType();
2317 
2318   bool SrcVec = SrcTy->isVectorTy();
2319   bool DstVec = DestTy->isVectorTy();
2320 
2321   Assert(SrcVec == DstVec,
2322          "UIToFP source and dest must both be vector or scalar", &I);
2323   Assert(SrcTy->isIntOrIntVectorTy(),
2324          "UIToFP source must be integer or integer vector", &I);
2325   Assert(DestTy->isFPOrFPVectorTy(), "UIToFP result must be FP or FP vector",
2326          &I);
2327 
2328   if (SrcVec && DstVec)
2329     Assert(cast<VectorType>(SrcTy)->getNumElements() ==
2330                cast<VectorType>(DestTy)->getNumElements(),
2331            "UIToFP source and dest vector length mismatch", &I);
2332 
2333   visitInstruction(I);
2334 }
2335 
visitSIToFPInst(SIToFPInst & I)2336 void Verifier::visitSIToFPInst(SIToFPInst &I) {
2337   // Get the source and destination types
2338   Type *SrcTy = I.getOperand(0)->getType();
2339   Type *DestTy = I.getType();
2340 
2341   bool SrcVec = SrcTy->isVectorTy();
2342   bool DstVec = DestTy->isVectorTy();
2343 
2344   Assert(SrcVec == DstVec,
2345          "SIToFP source and dest must both be vector or scalar", &I);
2346   Assert(SrcTy->isIntOrIntVectorTy(),
2347          "SIToFP source must be integer or integer vector", &I);
2348   Assert(DestTy->isFPOrFPVectorTy(), "SIToFP result must be FP or FP vector",
2349          &I);
2350 
2351   if (SrcVec && DstVec)
2352     Assert(cast<VectorType>(SrcTy)->getNumElements() ==
2353                cast<VectorType>(DestTy)->getNumElements(),
2354            "SIToFP source and dest vector length mismatch", &I);
2355 
2356   visitInstruction(I);
2357 }
2358 
visitFPToUIInst(FPToUIInst & I)2359 void Verifier::visitFPToUIInst(FPToUIInst &I) {
2360   // Get the source and destination types
2361   Type *SrcTy = I.getOperand(0)->getType();
2362   Type *DestTy = I.getType();
2363 
2364   bool SrcVec = SrcTy->isVectorTy();
2365   bool DstVec = DestTy->isVectorTy();
2366 
2367   Assert(SrcVec == DstVec,
2368          "FPToUI source and dest must both be vector or scalar", &I);
2369   Assert(SrcTy->isFPOrFPVectorTy(), "FPToUI source must be FP or FP vector",
2370          &I);
2371   Assert(DestTy->isIntOrIntVectorTy(),
2372          "FPToUI result must be integer or integer vector", &I);
2373 
2374   if (SrcVec && DstVec)
2375     Assert(cast<VectorType>(SrcTy)->getNumElements() ==
2376                cast<VectorType>(DestTy)->getNumElements(),
2377            "FPToUI source and dest vector length mismatch", &I);
2378 
2379   visitInstruction(I);
2380 }
2381 
visitFPToSIInst(FPToSIInst & I)2382 void Verifier::visitFPToSIInst(FPToSIInst &I) {
2383   // Get the source and destination types
2384   Type *SrcTy = I.getOperand(0)->getType();
2385   Type *DestTy = I.getType();
2386 
2387   bool SrcVec = SrcTy->isVectorTy();
2388   bool DstVec = DestTy->isVectorTy();
2389 
2390   Assert(SrcVec == DstVec,
2391          "FPToSI source and dest must both be vector or scalar", &I);
2392   Assert(SrcTy->isFPOrFPVectorTy(), "FPToSI source must be FP or FP vector",
2393          &I);
2394   Assert(DestTy->isIntOrIntVectorTy(),
2395          "FPToSI result must be integer or integer vector", &I);
2396 
2397   if (SrcVec && DstVec)
2398     Assert(cast<VectorType>(SrcTy)->getNumElements() ==
2399                cast<VectorType>(DestTy)->getNumElements(),
2400            "FPToSI source and dest vector length mismatch", &I);
2401 
2402   visitInstruction(I);
2403 }
2404 
visitPtrToIntInst(PtrToIntInst & I)2405 void Verifier::visitPtrToIntInst(PtrToIntInst &I) {
2406   // Get the source and destination types
2407   Type *SrcTy = I.getOperand(0)->getType();
2408   Type *DestTy = I.getType();
2409 
2410   Assert(SrcTy->getScalarType()->isPointerTy(),
2411          "PtrToInt source must be pointer", &I);
2412   Assert(DestTy->getScalarType()->isIntegerTy(),
2413          "PtrToInt result must be integral", &I);
2414   Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(), "PtrToInt type mismatch",
2415          &I);
2416 
2417   if (SrcTy->isVectorTy()) {
2418     VectorType *VSrc = dyn_cast<VectorType>(SrcTy);
2419     VectorType *VDest = dyn_cast<VectorType>(DestTy);
2420     Assert(VSrc->getNumElements() == VDest->getNumElements(),
2421            "PtrToInt Vector width mismatch", &I);
2422   }
2423 
2424   visitInstruction(I);
2425 }
2426 
visitIntToPtrInst(IntToPtrInst & I)2427 void Verifier::visitIntToPtrInst(IntToPtrInst &I) {
2428   // Get the source and destination types
2429   Type *SrcTy = I.getOperand(0)->getType();
2430   Type *DestTy = I.getType();
2431 
2432   Assert(SrcTy->getScalarType()->isIntegerTy(),
2433          "IntToPtr source must be an integral", &I);
2434   Assert(DestTy->getScalarType()->isPointerTy(),
2435          "IntToPtr result must be a pointer", &I);
2436   Assert(SrcTy->isVectorTy() == DestTy->isVectorTy(), "IntToPtr type mismatch",
2437          &I);
2438   if (SrcTy->isVectorTy()) {
2439     VectorType *VSrc = dyn_cast<VectorType>(SrcTy);
2440     VectorType *VDest = dyn_cast<VectorType>(DestTy);
2441     Assert(VSrc->getNumElements() == VDest->getNumElements(),
2442            "IntToPtr Vector width mismatch", &I);
2443   }
2444   visitInstruction(I);
2445 }
2446 
visitBitCastInst(BitCastInst & I)2447 void Verifier::visitBitCastInst(BitCastInst &I) {
2448   Assert(
2449       CastInst::castIsValid(Instruction::BitCast, I.getOperand(0), I.getType()),
2450       "Invalid bitcast", &I);
2451   visitInstruction(I);
2452 }
2453 
visitAddrSpaceCastInst(AddrSpaceCastInst & I)2454 void Verifier::visitAddrSpaceCastInst(AddrSpaceCastInst &I) {
2455   Type *SrcTy = I.getOperand(0)->getType();
2456   Type *DestTy = I.getType();
2457 
2458   Assert(SrcTy->isPtrOrPtrVectorTy(), "AddrSpaceCast source must be a pointer",
2459          &I);
2460   Assert(DestTy->isPtrOrPtrVectorTy(), "AddrSpaceCast result must be a pointer",
2461          &I);
2462   Assert(SrcTy->getPointerAddressSpace() != DestTy->getPointerAddressSpace(),
2463          "AddrSpaceCast must be between different address spaces", &I);
2464   if (SrcTy->isVectorTy())
2465     Assert(SrcTy->getVectorNumElements() == DestTy->getVectorNumElements(),
2466            "AddrSpaceCast vector pointer number of elements mismatch", &I);
2467   visitInstruction(I);
2468 }
2469 
2470 /// visitPHINode - Ensure that a PHI node is well formed.
2471 ///
visitPHINode(PHINode & PN)2472 void Verifier::visitPHINode(PHINode &PN) {
2473   // Ensure that the PHI nodes are all grouped together at the top of the block.
2474   // This can be tested by checking whether the instruction before this is
2475   // either nonexistent (because this is begin()) or is a PHI node.  If not,
2476   // then there is some other instruction before a PHI.
2477   Assert(&PN == &PN.getParent()->front() ||
2478              isa<PHINode>(--BasicBlock::iterator(&PN)),
2479          "PHI nodes not grouped at top of basic block!", &PN, PN.getParent());
2480 
2481   // Check that a PHI doesn't yield a Token.
2482   Assert(!PN.getType()->isTokenTy(), "PHI nodes cannot have token type!");
2483 
2484   // Check that all of the values of the PHI node have the same type as the
2485   // result, and that the incoming blocks are really basic blocks.
2486   for (Value *IncValue : PN.incoming_values()) {
2487     Assert(PN.getType() == IncValue->getType(),
2488            "PHI node operands are not the same type as the result!", &PN);
2489   }
2490 
2491   // All other PHI node constraints are checked in the visitBasicBlock method.
2492 
2493   visitInstruction(PN);
2494 }
2495 
verifyCallSite(CallSite CS)2496 void Verifier::verifyCallSite(CallSite CS) {
2497   Instruction *I = CS.getInstruction();
2498 
2499   Assert(CS.getCalledValue()->getType()->isPointerTy(),
2500          "Called function must be a pointer!", I);
2501   PointerType *FPTy = cast<PointerType>(CS.getCalledValue()->getType());
2502 
2503   Assert(FPTy->getElementType()->isFunctionTy(),
2504          "Called function is not pointer to function type!", I);
2505 
2506   Assert(FPTy->getElementType() == CS.getFunctionType(),
2507          "Called function is not the same type as the call!", I);
2508 
2509   FunctionType *FTy = CS.getFunctionType();
2510 
2511   // Verify that the correct number of arguments are being passed
2512   if (FTy->isVarArg())
2513     Assert(CS.arg_size() >= FTy->getNumParams(),
2514            "Called function requires more parameters than were provided!", I);
2515   else
2516     Assert(CS.arg_size() == FTy->getNumParams(),
2517            "Incorrect number of arguments passed to called function!", I);
2518 
2519   // Verify that all arguments to the call match the function type.
2520   for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
2521     Assert(CS.getArgument(i)->getType() == FTy->getParamType(i),
2522            "Call parameter type does not match function signature!",
2523            CS.getArgument(i), FTy->getParamType(i), I);
2524 
2525   AttributeSet Attrs = CS.getAttributes();
2526 
2527   Assert(verifyAttributeCount(Attrs, CS.arg_size()),
2528          "Attribute after last parameter!", I);
2529 
2530   // Verify call attributes.
2531   verifyFunctionAttrs(FTy, Attrs, I);
2532 
2533   // Conservatively check the inalloca argument.
2534   // We have a bug if we can find that there is an underlying alloca without
2535   // inalloca.
2536   if (CS.hasInAllocaArgument()) {
2537     Value *InAllocaArg = CS.getArgument(FTy->getNumParams() - 1);
2538     if (auto AI = dyn_cast<AllocaInst>(InAllocaArg->stripInBoundsOffsets()))
2539       Assert(AI->isUsedWithInAlloca(),
2540              "inalloca argument for call has mismatched alloca", AI, I);
2541   }
2542 
2543   // For each argument of the callsite, if it has the swifterror argument,
2544   // make sure the underlying alloca has swifterror as well.
2545   for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
2546     if (CS.paramHasAttr(i+1, Attribute::SwiftError)) {
2547       Value *SwiftErrorArg = CS.getArgument(i);
2548       auto AI = dyn_cast<AllocaInst>(SwiftErrorArg->stripInBoundsOffsets());
2549       Assert(AI, "swifterror argument should come from alloca", AI, I);
2550       if (AI)
2551         Assert(AI->isSwiftError(),
2552                "swifterror argument for call has mismatched alloca", AI, I);
2553     }
2554 
2555   if (FTy->isVarArg()) {
2556     // FIXME? is 'nest' even legal here?
2557     bool SawNest = false;
2558     bool SawReturned = false;
2559 
2560     for (unsigned Idx = 1; Idx < 1 + FTy->getNumParams(); ++Idx) {
2561       if (Attrs.hasAttribute(Idx, Attribute::Nest))
2562         SawNest = true;
2563       if (Attrs.hasAttribute(Idx, Attribute::Returned))
2564         SawReturned = true;
2565     }
2566 
2567     // Check attributes on the varargs part.
2568     for (unsigned Idx = 1 + FTy->getNumParams(); Idx <= CS.arg_size(); ++Idx) {
2569       Type *Ty = CS.getArgument(Idx-1)->getType();
2570       verifyParameterAttrs(Attrs, Idx, Ty, false, I);
2571 
2572       if (Attrs.hasAttribute(Idx, Attribute::Nest)) {
2573         Assert(!SawNest, "More than one parameter has attribute nest!", I);
2574         SawNest = true;
2575       }
2576 
2577       if (Attrs.hasAttribute(Idx, Attribute::Returned)) {
2578         Assert(!SawReturned, "More than one parameter has attribute returned!",
2579                I);
2580         Assert(Ty->canLosslesslyBitCastTo(FTy->getReturnType()),
2581                "Incompatible argument and return types for 'returned' "
2582                "attribute",
2583                I);
2584         SawReturned = true;
2585       }
2586 
2587       Assert(!Attrs.hasAttribute(Idx, Attribute::StructRet),
2588              "Attribute 'sret' cannot be used for vararg call arguments!", I);
2589 
2590       if (Attrs.hasAttribute(Idx, Attribute::InAlloca))
2591         Assert(Idx == CS.arg_size(), "inalloca isn't on the last argument!", I);
2592     }
2593   }
2594 
2595   // Verify that there's no metadata unless it's a direct call to an intrinsic.
2596   if (CS.getCalledFunction() == nullptr ||
2597       !CS.getCalledFunction()->getName().startswith("llvm.")) {
2598     for (Type *ParamTy : FTy->params()) {
2599       Assert(!ParamTy->isMetadataTy(),
2600              "Function has metadata parameter but isn't an intrinsic", I);
2601       Assert(!ParamTy->isTokenTy(),
2602              "Function has token parameter but isn't an intrinsic", I);
2603     }
2604   }
2605 
2606   // Verify that indirect calls don't return tokens.
2607   if (CS.getCalledFunction() == nullptr)
2608     Assert(!FTy->getReturnType()->isTokenTy(),
2609            "Return type cannot be token for indirect call!");
2610 
2611   if (Function *F = CS.getCalledFunction())
2612     if (Intrinsic::ID ID = (Intrinsic::ID)F->getIntrinsicID())
2613       visitIntrinsicCallSite(ID, CS);
2614 
2615   // Verify that a callsite has at most one "deopt", at most one "funclet" and
2616   // at most one "gc-transition" operand bundle.
2617   bool FoundDeoptBundle = false, FoundFuncletBundle = false,
2618        FoundGCTransitionBundle = false;
2619   for (unsigned i = 0, e = CS.getNumOperandBundles(); i < e; ++i) {
2620     OperandBundleUse BU = CS.getOperandBundleAt(i);
2621     uint32_t Tag = BU.getTagID();
2622     if (Tag == LLVMContext::OB_deopt) {
2623       Assert(!FoundDeoptBundle, "Multiple deopt operand bundles", I);
2624       FoundDeoptBundle = true;
2625     } else if (Tag == LLVMContext::OB_gc_transition) {
2626       Assert(!FoundGCTransitionBundle, "Multiple gc-transition operand bundles",
2627              I);
2628       FoundGCTransitionBundle = true;
2629     } else if (Tag == LLVMContext::OB_funclet) {
2630       Assert(!FoundFuncletBundle, "Multiple funclet operand bundles", I);
2631       FoundFuncletBundle = true;
2632       Assert(BU.Inputs.size() == 1,
2633              "Expected exactly one funclet bundle operand", I);
2634       Assert(isa<FuncletPadInst>(BU.Inputs.front()),
2635              "Funclet bundle operands should correspond to a FuncletPadInst",
2636              I);
2637     }
2638   }
2639 
2640   // Verify that each inlinable callsite of a debug-info-bearing function in a
2641   // debug-info-bearing function has a debug location attached to it. Failure to
2642   // do so causes assertion failures when the inliner sets up inline scope info.
2643   if (I->getFunction()->getSubprogram() && CS.getCalledFunction() &&
2644       CS.getCalledFunction()->getSubprogram())
2645     Assert(I->getDebugLoc(), "inlinable function call in a function with debug "
2646                              "info must have a !dbg location",
2647            I);
2648 
2649   visitInstruction(*I);
2650 }
2651 
2652 /// Two types are "congruent" if they are identical, or if they are both pointer
2653 /// types with different pointee types and the same address space.
isTypeCongruent(Type * L,Type * R)2654 static bool isTypeCongruent(Type *L, Type *R) {
2655   if (L == R)
2656     return true;
2657   PointerType *PL = dyn_cast<PointerType>(L);
2658   PointerType *PR = dyn_cast<PointerType>(R);
2659   if (!PL || !PR)
2660     return false;
2661   return PL->getAddressSpace() == PR->getAddressSpace();
2662 }
2663 
getParameterABIAttributes(int I,AttributeSet Attrs)2664 static AttrBuilder getParameterABIAttributes(int I, AttributeSet Attrs) {
2665   static const Attribute::AttrKind ABIAttrs[] = {
2666       Attribute::StructRet, Attribute::ByVal, Attribute::InAlloca,
2667       Attribute::InReg, Attribute::Returned, Attribute::SwiftSelf,
2668       Attribute::SwiftError};
2669   AttrBuilder Copy;
2670   for (auto AK : ABIAttrs) {
2671     if (Attrs.hasAttribute(I + 1, AK))
2672       Copy.addAttribute(AK);
2673   }
2674   if (Attrs.hasAttribute(I + 1, Attribute::Alignment))
2675     Copy.addAlignmentAttr(Attrs.getParamAlignment(I + 1));
2676   return Copy;
2677 }
2678 
verifyMustTailCall(CallInst & CI)2679 void Verifier::verifyMustTailCall(CallInst &CI) {
2680   Assert(!CI.isInlineAsm(), "cannot use musttail call with inline asm", &CI);
2681 
2682   // - The caller and callee prototypes must match.  Pointer types of
2683   //   parameters or return types may differ in pointee type, but not
2684   //   address space.
2685   Function *F = CI.getParent()->getParent();
2686   FunctionType *CallerTy = F->getFunctionType();
2687   FunctionType *CalleeTy = CI.getFunctionType();
2688   Assert(CallerTy->getNumParams() == CalleeTy->getNumParams(),
2689          "cannot guarantee tail call due to mismatched parameter counts", &CI);
2690   Assert(CallerTy->isVarArg() == CalleeTy->isVarArg(),
2691          "cannot guarantee tail call due to mismatched varargs", &CI);
2692   Assert(isTypeCongruent(CallerTy->getReturnType(), CalleeTy->getReturnType()),
2693          "cannot guarantee tail call due to mismatched return types", &CI);
2694   for (int I = 0, E = CallerTy->getNumParams(); I != E; ++I) {
2695     Assert(
2696         isTypeCongruent(CallerTy->getParamType(I), CalleeTy->getParamType(I)),
2697         "cannot guarantee tail call due to mismatched parameter types", &CI);
2698   }
2699 
2700   // - The calling conventions of the caller and callee must match.
2701   Assert(F->getCallingConv() == CI.getCallingConv(),
2702          "cannot guarantee tail call due to mismatched calling conv", &CI);
2703 
2704   // - All ABI-impacting function attributes, such as sret, byval, inreg,
2705   //   returned, and inalloca, must match.
2706   AttributeSet CallerAttrs = F->getAttributes();
2707   AttributeSet CalleeAttrs = CI.getAttributes();
2708   for (int I = 0, E = CallerTy->getNumParams(); I != E; ++I) {
2709     AttrBuilder CallerABIAttrs = getParameterABIAttributes(I, CallerAttrs);
2710     AttrBuilder CalleeABIAttrs = getParameterABIAttributes(I, CalleeAttrs);
2711     Assert(CallerABIAttrs == CalleeABIAttrs,
2712            "cannot guarantee tail call due to mismatched ABI impacting "
2713            "function attributes",
2714            &CI, CI.getOperand(I));
2715   }
2716 
2717   // - The call must immediately precede a :ref:`ret <i_ret>` instruction,
2718   //   or a pointer bitcast followed by a ret instruction.
2719   // - The ret instruction must return the (possibly bitcasted) value
2720   //   produced by the call or void.
2721   Value *RetVal = &CI;
2722   Instruction *Next = CI.getNextNode();
2723 
2724   // Handle the optional bitcast.
2725   if (BitCastInst *BI = dyn_cast_or_null<BitCastInst>(Next)) {
2726     Assert(BI->getOperand(0) == RetVal,
2727            "bitcast following musttail call must use the call", BI);
2728     RetVal = BI;
2729     Next = BI->getNextNode();
2730   }
2731 
2732   // Check the return.
2733   ReturnInst *Ret = dyn_cast_or_null<ReturnInst>(Next);
2734   Assert(Ret, "musttail call must be precede a ret with an optional bitcast",
2735          &CI);
2736   Assert(!Ret->getReturnValue() || Ret->getReturnValue() == RetVal,
2737          "musttail call result must be returned", Ret);
2738 }
2739 
visitCallInst(CallInst & CI)2740 void Verifier::visitCallInst(CallInst &CI) {
2741   verifyCallSite(&CI);
2742 
2743   if (CI.isMustTailCall())
2744     verifyMustTailCall(CI);
2745 }
2746 
visitInvokeInst(InvokeInst & II)2747 void Verifier::visitInvokeInst(InvokeInst &II) {
2748   verifyCallSite(&II);
2749 
2750   // Verify that the first non-PHI instruction of the unwind destination is an
2751   // exception handling instruction.
2752   Assert(
2753       II.getUnwindDest()->isEHPad(),
2754       "The unwind destination does not have an exception handling instruction!",
2755       &II);
2756 
2757   visitTerminatorInst(II);
2758 }
2759 
2760 /// visitBinaryOperator - Check that both arguments to the binary operator are
2761 /// of the same type!
2762 ///
visitBinaryOperator(BinaryOperator & B)2763 void Verifier::visitBinaryOperator(BinaryOperator &B) {
2764   Assert(B.getOperand(0)->getType() == B.getOperand(1)->getType(),
2765          "Both operands to a binary operator are not of the same type!", &B);
2766 
2767   switch (B.getOpcode()) {
2768   // Check that integer arithmetic operators are only used with
2769   // integral operands.
2770   case Instruction::Add:
2771   case Instruction::Sub:
2772   case Instruction::Mul:
2773   case Instruction::SDiv:
2774   case Instruction::UDiv:
2775   case Instruction::SRem:
2776   case Instruction::URem:
2777     Assert(B.getType()->isIntOrIntVectorTy(),
2778            "Integer arithmetic operators only work with integral types!", &B);
2779     Assert(B.getType() == B.getOperand(0)->getType(),
2780            "Integer arithmetic operators must have same type "
2781            "for operands and result!",
2782            &B);
2783     break;
2784   // Check that floating-point arithmetic operators are only used with
2785   // floating-point operands.
2786   case Instruction::FAdd:
2787   case Instruction::FSub:
2788   case Instruction::FMul:
2789   case Instruction::FDiv:
2790   case Instruction::FRem:
2791     Assert(B.getType()->isFPOrFPVectorTy(),
2792            "Floating-point arithmetic operators only work with "
2793            "floating-point types!",
2794            &B);
2795     Assert(B.getType() == B.getOperand(0)->getType(),
2796            "Floating-point arithmetic operators must have same type "
2797            "for operands and result!",
2798            &B);
2799     break;
2800   // Check that logical operators are only used with integral operands.
2801   case Instruction::And:
2802   case Instruction::Or:
2803   case Instruction::Xor:
2804     Assert(B.getType()->isIntOrIntVectorTy(),
2805            "Logical operators only work with integral types!", &B);
2806     Assert(B.getType() == B.getOperand(0)->getType(),
2807            "Logical operators must have same type for operands and result!",
2808            &B);
2809     break;
2810   case Instruction::Shl:
2811   case Instruction::LShr:
2812   case Instruction::AShr:
2813     Assert(B.getType()->isIntOrIntVectorTy(),
2814            "Shifts only work with integral types!", &B);
2815     Assert(B.getType() == B.getOperand(0)->getType(),
2816            "Shift return type must be same as operands!", &B);
2817     break;
2818   default:
2819     llvm_unreachable("Unknown BinaryOperator opcode!");
2820   }
2821 
2822   visitInstruction(B);
2823 }
2824 
visitICmpInst(ICmpInst & IC)2825 void Verifier::visitICmpInst(ICmpInst &IC) {
2826   // Check that the operands are the same type
2827   Type *Op0Ty = IC.getOperand(0)->getType();
2828   Type *Op1Ty = IC.getOperand(1)->getType();
2829   Assert(Op0Ty == Op1Ty,
2830          "Both operands to ICmp instruction are not of the same type!", &IC);
2831   // Check that the operands are the right type
2832   Assert(Op0Ty->isIntOrIntVectorTy() || Op0Ty->getScalarType()->isPointerTy(),
2833          "Invalid operand types for ICmp instruction", &IC);
2834   // Check that the predicate is valid.
2835   Assert(IC.getPredicate() >= CmpInst::FIRST_ICMP_PREDICATE &&
2836              IC.getPredicate() <= CmpInst::LAST_ICMP_PREDICATE,
2837          "Invalid predicate in ICmp instruction!", &IC);
2838 
2839   visitInstruction(IC);
2840 }
2841 
visitFCmpInst(FCmpInst & FC)2842 void Verifier::visitFCmpInst(FCmpInst &FC) {
2843   // Check that the operands are the same type
2844   Type *Op0Ty = FC.getOperand(0)->getType();
2845   Type *Op1Ty = FC.getOperand(1)->getType();
2846   Assert(Op0Ty == Op1Ty,
2847          "Both operands to FCmp instruction are not of the same type!", &FC);
2848   // Check that the operands are the right type
2849   Assert(Op0Ty->isFPOrFPVectorTy(),
2850          "Invalid operand types for FCmp instruction", &FC);
2851   // Check that the predicate is valid.
2852   Assert(FC.getPredicate() >= CmpInst::FIRST_FCMP_PREDICATE &&
2853              FC.getPredicate() <= CmpInst::LAST_FCMP_PREDICATE,
2854          "Invalid predicate in FCmp instruction!", &FC);
2855 
2856   visitInstruction(FC);
2857 }
2858 
visitExtractElementInst(ExtractElementInst & EI)2859 void Verifier::visitExtractElementInst(ExtractElementInst &EI) {
2860   Assert(
2861       ExtractElementInst::isValidOperands(EI.getOperand(0), EI.getOperand(1)),
2862       "Invalid extractelement operands!", &EI);
2863   visitInstruction(EI);
2864 }
2865 
visitInsertElementInst(InsertElementInst & IE)2866 void Verifier::visitInsertElementInst(InsertElementInst &IE) {
2867   Assert(InsertElementInst::isValidOperands(IE.getOperand(0), IE.getOperand(1),
2868                                             IE.getOperand(2)),
2869          "Invalid insertelement operands!", &IE);
2870   visitInstruction(IE);
2871 }
2872 
visitShuffleVectorInst(ShuffleVectorInst & SV)2873 void Verifier::visitShuffleVectorInst(ShuffleVectorInst &SV) {
2874   Assert(ShuffleVectorInst::isValidOperands(SV.getOperand(0), SV.getOperand(1),
2875                                             SV.getOperand(2)),
2876          "Invalid shufflevector operands!", &SV);
2877   visitInstruction(SV);
2878 }
2879 
visitGetElementPtrInst(GetElementPtrInst & GEP)2880 void Verifier::visitGetElementPtrInst(GetElementPtrInst &GEP) {
2881   Type *TargetTy = GEP.getPointerOperandType()->getScalarType();
2882 
2883   Assert(isa<PointerType>(TargetTy),
2884          "GEP base pointer is not a vector or a vector of pointers", &GEP);
2885   Assert(GEP.getSourceElementType()->isSized(), "GEP into unsized type!", &GEP);
2886   SmallVector<Value*, 16> Idxs(GEP.idx_begin(), GEP.idx_end());
2887   Type *ElTy =
2888       GetElementPtrInst::getIndexedType(GEP.getSourceElementType(), Idxs);
2889   Assert(ElTy, "Invalid indices for GEP pointer type!", &GEP);
2890 
2891   Assert(GEP.getType()->getScalarType()->isPointerTy() &&
2892              GEP.getResultElementType() == ElTy,
2893          "GEP is not of right type for indices!", &GEP, ElTy);
2894 
2895   if (GEP.getType()->isVectorTy()) {
2896     // Additional checks for vector GEPs.
2897     unsigned GEPWidth = GEP.getType()->getVectorNumElements();
2898     if (GEP.getPointerOperandType()->isVectorTy())
2899       Assert(GEPWidth == GEP.getPointerOperandType()->getVectorNumElements(),
2900              "Vector GEP result width doesn't match operand's", &GEP);
2901     for (Value *Idx : Idxs) {
2902       Type *IndexTy = Idx->getType();
2903       if (IndexTy->isVectorTy()) {
2904         unsigned IndexWidth = IndexTy->getVectorNumElements();
2905         Assert(IndexWidth == GEPWidth, "Invalid GEP index vector width", &GEP);
2906       }
2907       Assert(IndexTy->getScalarType()->isIntegerTy(),
2908              "All GEP indices should be of integer type");
2909     }
2910   }
2911   visitInstruction(GEP);
2912 }
2913 
isContiguous(const ConstantRange & A,const ConstantRange & B)2914 static bool isContiguous(const ConstantRange &A, const ConstantRange &B) {
2915   return A.getUpper() == B.getLower() || A.getLower() == B.getUpper();
2916 }
2917 
visitRangeMetadata(Instruction & I,MDNode * Range,Type * Ty)2918 void Verifier::visitRangeMetadata(Instruction& I,
2919                                   MDNode* Range, Type* Ty) {
2920   assert(Range &&
2921          Range == I.getMetadata(LLVMContext::MD_range) &&
2922          "precondition violation");
2923 
2924   unsigned NumOperands = Range->getNumOperands();
2925   Assert(NumOperands % 2 == 0, "Unfinished range!", Range);
2926   unsigned NumRanges = NumOperands / 2;
2927   Assert(NumRanges >= 1, "It should have at least one range!", Range);
2928 
2929   ConstantRange LastRange(1); // Dummy initial value
2930   for (unsigned i = 0; i < NumRanges; ++i) {
2931     ConstantInt *Low =
2932         mdconst::dyn_extract<ConstantInt>(Range->getOperand(2 * i));
2933     Assert(Low, "The lower limit must be an integer!", Low);
2934     ConstantInt *High =
2935         mdconst::dyn_extract<ConstantInt>(Range->getOperand(2 * i + 1));
2936     Assert(High, "The upper limit must be an integer!", High);
2937     Assert(High->getType() == Low->getType() && High->getType() == Ty,
2938            "Range types must match instruction type!", &I);
2939 
2940     APInt HighV = High->getValue();
2941     APInt LowV = Low->getValue();
2942     ConstantRange CurRange(LowV, HighV);
2943     Assert(!CurRange.isEmptySet() && !CurRange.isFullSet(),
2944            "Range must not be empty!", Range);
2945     if (i != 0) {
2946       Assert(CurRange.intersectWith(LastRange).isEmptySet(),
2947              "Intervals are overlapping", Range);
2948       Assert(LowV.sgt(LastRange.getLower()), "Intervals are not in order",
2949              Range);
2950       Assert(!isContiguous(CurRange, LastRange), "Intervals are contiguous",
2951              Range);
2952     }
2953     LastRange = ConstantRange(LowV, HighV);
2954   }
2955   if (NumRanges > 2) {
2956     APInt FirstLow =
2957         mdconst::dyn_extract<ConstantInt>(Range->getOperand(0))->getValue();
2958     APInt FirstHigh =
2959         mdconst::dyn_extract<ConstantInt>(Range->getOperand(1))->getValue();
2960     ConstantRange FirstRange(FirstLow, FirstHigh);
2961     Assert(FirstRange.intersectWith(LastRange).isEmptySet(),
2962            "Intervals are overlapping", Range);
2963     Assert(!isContiguous(FirstRange, LastRange), "Intervals are contiguous",
2964            Range);
2965   }
2966 }
2967 
checkAtomicMemAccessSize(const Module * M,Type * Ty,const Instruction * I)2968 void Verifier::checkAtomicMemAccessSize(const Module *M, Type *Ty,
2969                                         const Instruction *I) {
2970   unsigned Size = M->getDataLayout().getTypeSizeInBits(Ty);
2971   Assert(Size >= 8, "atomic memory access' size must be byte-sized", Ty, I);
2972   Assert(!(Size & (Size - 1)),
2973          "atomic memory access' operand must have a power-of-two size", Ty, I);
2974 }
2975 
visitLoadInst(LoadInst & LI)2976 void Verifier::visitLoadInst(LoadInst &LI) {
2977   PointerType *PTy = dyn_cast<PointerType>(LI.getOperand(0)->getType());
2978   Assert(PTy, "Load operand must be a pointer.", &LI);
2979   Type *ElTy = LI.getType();
2980   Assert(LI.getAlignment() <= Value::MaximumAlignment,
2981          "huge alignment values are unsupported", &LI);
2982   Assert(ElTy->isSized(), "loading unsized types is not allowed", &LI);
2983   if (LI.isAtomic()) {
2984     Assert(LI.getOrdering() != AtomicOrdering::Release &&
2985                LI.getOrdering() != AtomicOrdering::AcquireRelease,
2986            "Load cannot have Release ordering", &LI);
2987     Assert(LI.getAlignment() != 0,
2988            "Atomic load must specify explicit alignment", &LI);
2989     Assert(ElTy->isIntegerTy() || ElTy->isPointerTy() ||
2990                ElTy->isFloatingPointTy(),
2991            "atomic load operand must have integer, pointer, or floating point "
2992            "type!",
2993            ElTy, &LI);
2994     checkAtomicMemAccessSize(M, ElTy, &LI);
2995   } else {
2996     Assert(LI.getSynchScope() == CrossThread,
2997            "Non-atomic load cannot have SynchronizationScope specified", &LI);
2998   }
2999 
3000   visitInstruction(LI);
3001 }
3002 
visitStoreInst(StoreInst & SI)3003 void Verifier::visitStoreInst(StoreInst &SI) {
3004   PointerType *PTy = dyn_cast<PointerType>(SI.getOperand(1)->getType());
3005   Assert(PTy, "Store operand must be a pointer.", &SI);
3006   Type *ElTy = PTy->getElementType();
3007   Assert(ElTy == SI.getOperand(0)->getType(),
3008          "Stored value type does not match pointer operand type!", &SI, ElTy);
3009   Assert(SI.getAlignment() <= Value::MaximumAlignment,
3010          "huge alignment values are unsupported", &SI);
3011   Assert(ElTy->isSized(), "storing unsized types is not allowed", &SI);
3012   if (SI.isAtomic()) {
3013     Assert(SI.getOrdering() != AtomicOrdering::Acquire &&
3014                SI.getOrdering() != AtomicOrdering::AcquireRelease,
3015            "Store cannot have Acquire ordering", &SI);
3016     Assert(SI.getAlignment() != 0,
3017            "Atomic store must specify explicit alignment", &SI);
3018     Assert(ElTy->isIntegerTy() || ElTy->isPointerTy() ||
3019                ElTy->isFloatingPointTy(),
3020            "atomic store operand must have integer, pointer, or floating point "
3021            "type!",
3022            ElTy, &SI);
3023     checkAtomicMemAccessSize(M, ElTy, &SI);
3024   } else {
3025     Assert(SI.getSynchScope() == CrossThread,
3026            "Non-atomic store cannot have SynchronizationScope specified", &SI);
3027   }
3028   visitInstruction(SI);
3029 }
3030 
3031 /// Check that SwiftErrorVal is used as a swifterror argument in CS.
verifySwiftErrorCallSite(CallSite CS,const Value * SwiftErrorVal)3032 void Verifier::verifySwiftErrorCallSite(CallSite CS,
3033                                         const Value *SwiftErrorVal) {
3034   unsigned Idx = 0;
3035   for (CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end();
3036        I != E; ++I, ++Idx) {
3037     if (*I == SwiftErrorVal) {
3038       Assert(CS.paramHasAttr(Idx+1, Attribute::SwiftError),
3039              "swifterror value when used in a callsite should be marked "
3040              "with swifterror attribute",
3041               SwiftErrorVal, CS);
3042     }
3043   }
3044 }
3045 
verifySwiftErrorValue(const Value * SwiftErrorVal)3046 void Verifier::verifySwiftErrorValue(const Value *SwiftErrorVal) {
3047   // Check that swifterror value is only used by loads, stores, or as
3048   // a swifterror argument.
3049   for (const User *U : SwiftErrorVal->users()) {
3050     Assert(isa<LoadInst>(U) || isa<StoreInst>(U) || isa<CallInst>(U) ||
3051            isa<InvokeInst>(U),
3052            "swifterror value can only be loaded and stored from, or "
3053            "as a swifterror argument!",
3054            SwiftErrorVal, U);
3055     // If it is used by a store, check it is the second operand.
3056     if (auto StoreI = dyn_cast<StoreInst>(U))
3057       Assert(StoreI->getOperand(1) == SwiftErrorVal,
3058              "swifterror value should be the second operand when used "
3059              "by stores", SwiftErrorVal, U);
3060     if (auto CallI = dyn_cast<CallInst>(U))
3061       verifySwiftErrorCallSite(const_cast<CallInst*>(CallI), SwiftErrorVal);
3062     if (auto II = dyn_cast<InvokeInst>(U))
3063       verifySwiftErrorCallSite(const_cast<InvokeInst*>(II), SwiftErrorVal);
3064   }
3065 }
3066 
visitAllocaInst(AllocaInst & AI)3067 void Verifier::visitAllocaInst(AllocaInst &AI) {
3068   SmallPtrSet<Type*, 4> Visited;
3069   PointerType *PTy = AI.getType();
3070   Assert(PTy->getAddressSpace() == 0,
3071          "Allocation instruction pointer not in the generic address space!",
3072          &AI);
3073   Assert(AI.getAllocatedType()->isSized(&Visited),
3074          "Cannot allocate unsized type", &AI);
3075   Assert(AI.getArraySize()->getType()->isIntegerTy(),
3076          "Alloca array size must have integer type", &AI);
3077   Assert(AI.getAlignment() <= Value::MaximumAlignment,
3078          "huge alignment values are unsupported", &AI);
3079 
3080   if (AI.isSwiftError()) {
3081     verifySwiftErrorValue(&AI);
3082   }
3083 
3084   visitInstruction(AI);
3085 }
3086 
visitAtomicCmpXchgInst(AtomicCmpXchgInst & CXI)3087 void Verifier::visitAtomicCmpXchgInst(AtomicCmpXchgInst &CXI) {
3088 
3089   // FIXME: more conditions???
3090   Assert(CXI.getSuccessOrdering() != AtomicOrdering::NotAtomic,
3091          "cmpxchg instructions must be atomic.", &CXI);
3092   Assert(CXI.getFailureOrdering() != AtomicOrdering::NotAtomic,
3093          "cmpxchg instructions must be atomic.", &CXI);
3094   Assert(CXI.getSuccessOrdering() != AtomicOrdering::Unordered,
3095          "cmpxchg instructions cannot be unordered.", &CXI);
3096   Assert(CXI.getFailureOrdering() != AtomicOrdering::Unordered,
3097          "cmpxchg instructions cannot be unordered.", &CXI);
3098   Assert(!isStrongerThan(CXI.getFailureOrdering(), CXI.getSuccessOrdering()),
3099          "cmpxchg instructions failure argument shall be no stronger than the "
3100          "success argument",
3101          &CXI);
3102   Assert(CXI.getFailureOrdering() != AtomicOrdering::Release &&
3103              CXI.getFailureOrdering() != AtomicOrdering::AcquireRelease,
3104          "cmpxchg failure ordering cannot include release semantics", &CXI);
3105 
3106   PointerType *PTy = dyn_cast<PointerType>(CXI.getOperand(0)->getType());
3107   Assert(PTy, "First cmpxchg operand must be a pointer.", &CXI);
3108   Type *ElTy = PTy->getElementType();
3109   Assert(ElTy->isIntegerTy() || ElTy->isPointerTy(),
3110         "cmpxchg operand must have integer or pointer type",
3111          ElTy, &CXI);
3112   checkAtomicMemAccessSize(M, ElTy, &CXI);
3113   Assert(ElTy == CXI.getOperand(1)->getType(),
3114          "Expected value type does not match pointer operand type!", &CXI,
3115          ElTy);
3116   Assert(ElTy == CXI.getOperand(2)->getType(),
3117          "Stored value type does not match pointer operand type!", &CXI, ElTy);
3118   visitInstruction(CXI);
3119 }
3120 
visitAtomicRMWInst(AtomicRMWInst & RMWI)3121 void Verifier::visitAtomicRMWInst(AtomicRMWInst &RMWI) {
3122   Assert(RMWI.getOrdering() != AtomicOrdering::NotAtomic,
3123          "atomicrmw instructions must be atomic.", &RMWI);
3124   Assert(RMWI.getOrdering() != AtomicOrdering::Unordered,
3125          "atomicrmw instructions cannot be unordered.", &RMWI);
3126   PointerType *PTy = dyn_cast<PointerType>(RMWI.getOperand(0)->getType());
3127   Assert(PTy, "First atomicrmw operand must be a pointer.", &RMWI);
3128   Type *ElTy = PTy->getElementType();
3129   Assert(ElTy->isIntegerTy(), "atomicrmw operand must have integer type!",
3130          &RMWI, ElTy);
3131   checkAtomicMemAccessSize(M, ElTy, &RMWI);
3132   Assert(ElTy == RMWI.getOperand(1)->getType(),
3133          "Argument value type does not match pointer operand type!", &RMWI,
3134          ElTy);
3135   Assert(AtomicRMWInst::FIRST_BINOP <= RMWI.getOperation() &&
3136              RMWI.getOperation() <= AtomicRMWInst::LAST_BINOP,
3137          "Invalid binary operation!", &RMWI);
3138   visitInstruction(RMWI);
3139 }
3140 
visitFenceInst(FenceInst & FI)3141 void Verifier::visitFenceInst(FenceInst &FI) {
3142   const AtomicOrdering Ordering = FI.getOrdering();
3143   Assert(Ordering == AtomicOrdering::Acquire ||
3144              Ordering == AtomicOrdering::Release ||
3145              Ordering == AtomicOrdering::AcquireRelease ||
3146              Ordering == AtomicOrdering::SequentiallyConsistent,
3147          "fence instructions may only have acquire, release, acq_rel, or "
3148          "seq_cst ordering.",
3149          &FI);
3150   visitInstruction(FI);
3151 }
3152 
visitExtractValueInst(ExtractValueInst & EVI)3153 void Verifier::visitExtractValueInst(ExtractValueInst &EVI) {
3154   Assert(ExtractValueInst::getIndexedType(EVI.getAggregateOperand()->getType(),
3155                                           EVI.getIndices()) == EVI.getType(),
3156          "Invalid ExtractValueInst operands!", &EVI);
3157 
3158   visitInstruction(EVI);
3159 }
3160 
visitInsertValueInst(InsertValueInst & IVI)3161 void Verifier::visitInsertValueInst(InsertValueInst &IVI) {
3162   Assert(ExtractValueInst::getIndexedType(IVI.getAggregateOperand()->getType(),
3163                                           IVI.getIndices()) ==
3164              IVI.getOperand(1)->getType(),
3165          "Invalid InsertValueInst operands!", &IVI);
3166 
3167   visitInstruction(IVI);
3168 }
3169 
getParentPad(Value * EHPad)3170 static Value *getParentPad(Value *EHPad) {
3171   if (auto *FPI = dyn_cast<FuncletPadInst>(EHPad))
3172     return FPI->getParentPad();
3173 
3174   return cast<CatchSwitchInst>(EHPad)->getParentPad();
3175 }
3176 
visitEHPadPredecessors(Instruction & I)3177 void Verifier::visitEHPadPredecessors(Instruction &I) {
3178   assert(I.isEHPad());
3179 
3180   BasicBlock *BB = I.getParent();
3181   Function *F = BB->getParent();
3182 
3183   Assert(BB != &F->getEntryBlock(), "EH pad cannot be in entry block.", &I);
3184 
3185   if (auto *LPI = dyn_cast<LandingPadInst>(&I)) {
3186     // The landingpad instruction defines its parent as a landing pad block. The
3187     // landing pad block may be branched to only by the unwind edge of an
3188     // invoke.
3189     for (BasicBlock *PredBB : predecessors(BB)) {
3190       const auto *II = dyn_cast<InvokeInst>(PredBB->getTerminator());
3191       Assert(II && II->getUnwindDest() == BB && II->getNormalDest() != BB,
3192              "Block containing LandingPadInst must be jumped to "
3193              "only by the unwind edge of an invoke.",
3194              LPI);
3195     }
3196     return;
3197   }
3198   if (auto *CPI = dyn_cast<CatchPadInst>(&I)) {
3199     if (!pred_empty(BB))
3200       Assert(BB->getUniquePredecessor() == CPI->getCatchSwitch()->getParent(),
3201              "Block containg CatchPadInst must be jumped to "
3202              "only by its catchswitch.",
3203              CPI);
3204     Assert(BB != CPI->getCatchSwitch()->getUnwindDest(),
3205            "Catchswitch cannot unwind to one of its catchpads",
3206            CPI->getCatchSwitch(), CPI);
3207     return;
3208   }
3209 
3210   // Verify that each pred has a legal terminator with a legal to/from EH
3211   // pad relationship.
3212   Instruction *ToPad = &I;
3213   Value *ToPadParent = getParentPad(ToPad);
3214   for (BasicBlock *PredBB : predecessors(BB)) {
3215     TerminatorInst *TI = PredBB->getTerminator();
3216     Value *FromPad;
3217     if (auto *II = dyn_cast<InvokeInst>(TI)) {
3218       Assert(II->getUnwindDest() == BB && II->getNormalDest() != BB,
3219              "EH pad must be jumped to via an unwind edge", ToPad, II);
3220       if (auto Bundle = II->getOperandBundle(LLVMContext::OB_funclet))
3221         FromPad = Bundle->Inputs[0];
3222       else
3223         FromPad = ConstantTokenNone::get(II->getContext());
3224     } else if (auto *CRI = dyn_cast<CleanupReturnInst>(TI)) {
3225       FromPad = CRI->getOperand(0);
3226       Assert(FromPad != ToPadParent, "A cleanupret must exit its cleanup", CRI);
3227     } else if (auto *CSI = dyn_cast<CatchSwitchInst>(TI)) {
3228       FromPad = CSI;
3229     } else {
3230       Assert(false, "EH pad must be jumped to via an unwind edge", ToPad, TI);
3231     }
3232 
3233     // The edge may exit from zero or more nested pads.
3234     SmallSet<Value *, 8> Seen;
3235     for (;; FromPad = getParentPad(FromPad)) {
3236       Assert(FromPad != ToPad,
3237              "EH pad cannot handle exceptions raised within it", FromPad, TI);
3238       if (FromPad == ToPadParent) {
3239         // This is a legal unwind edge.
3240         break;
3241       }
3242       Assert(!isa<ConstantTokenNone>(FromPad),
3243              "A single unwind edge may only enter one EH pad", TI);
3244       Assert(Seen.insert(FromPad).second,
3245              "EH pad jumps through a cycle of pads", FromPad);
3246     }
3247   }
3248 }
3249 
visitLandingPadInst(LandingPadInst & LPI)3250 void Verifier::visitLandingPadInst(LandingPadInst &LPI) {
3251   // The landingpad instruction is ill-formed if it doesn't have any clauses and
3252   // isn't a cleanup.
3253   Assert(LPI.getNumClauses() > 0 || LPI.isCleanup(),
3254          "LandingPadInst needs at least one clause or to be a cleanup.", &LPI);
3255 
3256   visitEHPadPredecessors(LPI);
3257 
3258   if (!LandingPadResultTy)
3259     LandingPadResultTy = LPI.getType();
3260   else
3261     Assert(LandingPadResultTy == LPI.getType(),
3262            "The landingpad instruction should have a consistent result type "
3263            "inside a function.",
3264            &LPI);
3265 
3266   Function *F = LPI.getParent()->getParent();
3267   Assert(F->hasPersonalityFn(),
3268          "LandingPadInst needs to be in a function with a personality.", &LPI);
3269 
3270   // The landingpad instruction must be the first non-PHI instruction in the
3271   // block.
3272   Assert(LPI.getParent()->getLandingPadInst() == &LPI,
3273          "LandingPadInst not the first non-PHI instruction in the block.",
3274          &LPI);
3275 
3276   for (unsigned i = 0, e = LPI.getNumClauses(); i < e; ++i) {
3277     Constant *Clause = LPI.getClause(i);
3278     if (LPI.isCatch(i)) {
3279       Assert(isa<PointerType>(Clause->getType()),
3280              "Catch operand does not have pointer type!", &LPI);
3281     } else {
3282       Assert(LPI.isFilter(i), "Clause is neither catch nor filter!", &LPI);
3283       Assert(isa<ConstantArray>(Clause) || isa<ConstantAggregateZero>(Clause),
3284              "Filter operand is not an array of constants!", &LPI);
3285     }
3286   }
3287 
3288   visitInstruction(LPI);
3289 }
3290 
visitCatchPadInst(CatchPadInst & CPI)3291 void Verifier::visitCatchPadInst(CatchPadInst &CPI) {
3292   BasicBlock *BB = CPI.getParent();
3293 
3294   Function *F = BB->getParent();
3295   Assert(F->hasPersonalityFn(),
3296          "CatchPadInst needs to be in a function with a personality.", &CPI);
3297 
3298   Assert(isa<CatchSwitchInst>(CPI.getParentPad()),
3299          "CatchPadInst needs to be directly nested in a CatchSwitchInst.",
3300          CPI.getParentPad());
3301 
3302   // The catchpad instruction must be the first non-PHI instruction in the
3303   // block.
3304   Assert(BB->getFirstNonPHI() == &CPI,
3305          "CatchPadInst not the first non-PHI instruction in the block.", &CPI);
3306 
3307   visitEHPadPredecessors(CPI);
3308   visitFuncletPadInst(CPI);
3309 }
3310 
visitCatchReturnInst(CatchReturnInst & CatchReturn)3311 void Verifier::visitCatchReturnInst(CatchReturnInst &CatchReturn) {
3312   Assert(isa<CatchPadInst>(CatchReturn.getOperand(0)),
3313          "CatchReturnInst needs to be provided a CatchPad", &CatchReturn,
3314          CatchReturn.getOperand(0));
3315 
3316   visitTerminatorInst(CatchReturn);
3317 }
3318 
visitCleanupPadInst(CleanupPadInst & CPI)3319 void Verifier::visitCleanupPadInst(CleanupPadInst &CPI) {
3320   BasicBlock *BB = CPI.getParent();
3321 
3322   Function *F = BB->getParent();
3323   Assert(F->hasPersonalityFn(),
3324          "CleanupPadInst needs to be in a function with a personality.", &CPI);
3325 
3326   // The cleanuppad instruction must be the first non-PHI instruction in the
3327   // block.
3328   Assert(BB->getFirstNonPHI() == &CPI,
3329          "CleanupPadInst not the first non-PHI instruction in the block.",
3330          &CPI);
3331 
3332   auto *ParentPad = CPI.getParentPad();
3333   Assert(isa<ConstantTokenNone>(ParentPad) || isa<FuncletPadInst>(ParentPad),
3334          "CleanupPadInst has an invalid parent.", &CPI);
3335 
3336   visitEHPadPredecessors(CPI);
3337   visitFuncletPadInst(CPI);
3338 }
3339 
visitFuncletPadInst(FuncletPadInst & FPI)3340 void Verifier::visitFuncletPadInst(FuncletPadInst &FPI) {
3341   User *FirstUser = nullptr;
3342   Value *FirstUnwindPad = nullptr;
3343   SmallVector<FuncletPadInst *, 8> Worklist({&FPI});
3344   SmallSet<FuncletPadInst *, 8> Seen;
3345 
3346   while (!Worklist.empty()) {
3347     FuncletPadInst *CurrentPad = Worklist.pop_back_val();
3348     Assert(Seen.insert(CurrentPad).second,
3349            "FuncletPadInst must not be nested within itself", CurrentPad);
3350     Value *UnresolvedAncestorPad = nullptr;
3351     for (User *U : CurrentPad->users()) {
3352       BasicBlock *UnwindDest;
3353       if (auto *CRI = dyn_cast<CleanupReturnInst>(U)) {
3354         UnwindDest = CRI->getUnwindDest();
3355       } else if (auto *CSI = dyn_cast<CatchSwitchInst>(U)) {
3356         // We allow catchswitch unwind to caller to nest
3357         // within an outer pad that unwinds somewhere else,
3358         // because catchswitch doesn't have a nounwind variant.
3359         // See e.g. SimplifyCFGOpt::SimplifyUnreachable.
3360         if (CSI->unwindsToCaller())
3361           continue;
3362         UnwindDest = CSI->getUnwindDest();
3363       } else if (auto *II = dyn_cast<InvokeInst>(U)) {
3364         UnwindDest = II->getUnwindDest();
3365       } else if (isa<CallInst>(U)) {
3366         // Calls which don't unwind may be found inside funclet
3367         // pads that unwind somewhere else.  We don't *require*
3368         // such calls to be annotated nounwind.
3369         continue;
3370       } else if (auto *CPI = dyn_cast<CleanupPadInst>(U)) {
3371         // The unwind dest for a cleanup can only be found by
3372         // recursive search.  Add it to the worklist, and we'll
3373         // search for its first use that determines where it unwinds.
3374         Worklist.push_back(CPI);
3375         continue;
3376       } else {
3377         Assert(isa<CatchReturnInst>(U), "Bogus funclet pad use", U);
3378         continue;
3379       }
3380 
3381       Value *UnwindPad;
3382       bool ExitsFPI;
3383       if (UnwindDest) {
3384         UnwindPad = UnwindDest->getFirstNonPHI();
3385         if (!cast<Instruction>(UnwindPad)->isEHPad())
3386           continue;
3387         Value *UnwindParent = getParentPad(UnwindPad);
3388         // Ignore unwind edges that don't exit CurrentPad.
3389         if (UnwindParent == CurrentPad)
3390           continue;
3391         // Determine whether the original funclet pad is exited,
3392         // and if we are scanning nested pads determine how many
3393         // of them are exited so we can stop searching their
3394         // children.
3395         Value *ExitedPad = CurrentPad;
3396         ExitsFPI = false;
3397         do {
3398           if (ExitedPad == &FPI) {
3399             ExitsFPI = true;
3400             // Now we can resolve any ancestors of CurrentPad up to
3401             // FPI, but not including FPI since we need to make sure
3402             // to check all direct users of FPI for consistency.
3403             UnresolvedAncestorPad = &FPI;
3404             break;
3405           }
3406           Value *ExitedParent = getParentPad(ExitedPad);
3407           if (ExitedParent == UnwindParent) {
3408             // ExitedPad is the ancestor-most pad which this unwind
3409             // edge exits, so we can resolve up to it, meaning that
3410             // ExitedParent is the first ancestor still unresolved.
3411             UnresolvedAncestorPad = ExitedParent;
3412             break;
3413           }
3414           ExitedPad = ExitedParent;
3415         } while (!isa<ConstantTokenNone>(ExitedPad));
3416       } else {
3417         // Unwinding to caller exits all pads.
3418         UnwindPad = ConstantTokenNone::get(FPI.getContext());
3419         ExitsFPI = true;
3420         UnresolvedAncestorPad = &FPI;
3421       }
3422 
3423       if (ExitsFPI) {
3424         // This unwind edge exits FPI.  Make sure it agrees with other
3425         // such edges.
3426         if (FirstUser) {
3427           Assert(UnwindPad == FirstUnwindPad, "Unwind edges out of a funclet "
3428                                               "pad must have the same unwind "
3429                                               "dest",
3430                  &FPI, U, FirstUser);
3431         } else {
3432           FirstUser = U;
3433           FirstUnwindPad = UnwindPad;
3434           // Record cleanup sibling unwinds for verifySiblingFuncletUnwinds
3435           if (isa<CleanupPadInst>(&FPI) && !isa<ConstantTokenNone>(UnwindPad) &&
3436               getParentPad(UnwindPad) == getParentPad(&FPI))
3437             SiblingFuncletInfo[&FPI] = cast<TerminatorInst>(U);
3438         }
3439       }
3440       // Make sure we visit all uses of FPI, but for nested pads stop as
3441       // soon as we know where they unwind to.
3442       if (CurrentPad != &FPI)
3443         break;
3444     }
3445     if (UnresolvedAncestorPad) {
3446       if (CurrentPad == UnresolvedAncestorPad) {
3447         // When CurrentPad is FPI itself, we don't mark it as resolved even if
3448         // we've found an unwind edge that exits it, because we need to verify
3449         // all direct uses of FPI.
3450         assert(CurrentPad == &FPI);
3451         continue;
3452       }
3453       // Pop off the worklist any nested pads that we've found an unwind
3454       // destination for.  The pads on the worklist are the uncles,
3455       // great-uncles, etc. of CurrentPad.  We've found an unwind destination
3456       // for all ancestors of CurrentPad up to but not including
3457       // UnresolvedAncestorPad.
3458       Value *ResolvedPad = CurrentPad;
3459       while (!Worklist.empty()) {
3460         Value *UnclePad = Worklist.back();
3461         Value *AncestorPad = getParentPad(UnclePad);
3462         // Walk ResolvedPad up the ancestor list until we either find the
3463         // uncle's parent or the last resolved ancestor.
3464         while (ResolvedPad != AncestorPad) {
3465           Value *ResolvedParent = getParentPad(ResolvedPad);
3466           if (ResolvedParent == UnresolvedAncestorPad) {
3467             break;
3468           }
3469           ResolvedPad = ResolvedParent;
3470         }
3471         // If the resolved ancestor search didn't find the uncle's parent,
3472         // then the uncle is not yet resolved.
3473         if (ResolvedPad != AncestorPad)
3474           break;
3475         // This uncle is resolved, so pop it from the worklist.
3476         Worklist.pop_back();
3477       }
3478     }
3479   }
3480 
3481   if (FirstUnwindPad) {
3482     if (auto *CatchSwitch = dyn_cast<CatchSwitchInst>(FPI.getParentPad())) {
3483       BasicBlock *SwitchUnwindDest = CatchSwitch->getUnwindDest();
3484       Value *SwitchUnwindPad;
3485       if (SwitchUnwindDest)
3486         SwitchUnwindPad = SwitchUnwindDest->getFirstNonPHI();
3487       else
3488         SwitchUnwindPad = ConstantTokenNone::get(FPI.getContext());
3489       Assert(SwitchUnwindPad == FirstUnwindPad,
3490              "Unwind edges out of a catch must have the same unwind dest as "
3491              "the parent catchswitch",
3492              &FPI, FirstUser, CatchSwitch);
3493     }
3494   }
3495 
3496   visitInstruction(FPI);
3497 }
3498 
visitCatchSwitchInst(CatchSwitchInst & CatchSwitch)3499 void Verifier::visitCatchSwitchInst(CatchSwitchInst &CatchSwitch) {
3500   BasicBlock *BB = CatchSwitch.getParent();
3501 
3502   Function *F = BB->getParent();
3503   Assert(F->hasPersonalityFn(),
3504          "CatchSwitchInst needs to be in a function with a personality.",
3505          &CatchSwitch);
3506 
3507   // The catchswitch instruction must be the first non-PHI instruction in the
3508   // block.
3509   Assert(BB->getFirstNonPHI() == &CatchSwitch,
3510          "CatchSwitchInst not the first non-PHI instruction in the block.",
3511          &CatchSwitch);
3512 
3513   auto *ParentPad = CatchSwitch.getParentPad();
3514   Assert(isa<ConstantTokenNone>(ParentPad) || isa<FuncletPadInst>(ParentPad),
3515          "CatchSwitchInst has an invalid parent.", ParentPad);
3516 
3517   if (BasicBlock *UnwindDest = CatchSwitch.getUnwindDest()) {
3518     Instruction *I = UnwindDest->getFirstNonPHI();
3519     Assert(I->isEHPad() && !isa<LandingPadInst>(I),
3520            "CatchSwitchInst must unwind to an EH block which is not a "
3521            "landingpad.",
3522            &CatchSwitch);
3523 
3524     // Record catchswitch sibling unwinds for verifySiblingFuncletUnwinds
3525     if (getParentPad(I) == ParentPad)
3526       SiblingFuncletInfo[&CatchSwitch] = &CatchSwitch;
3527   }
3528 
3529   Assert(CatchSwitch.getNumHandlers() != 0,
3530          "CatchSwitchInst cannot have empty handler list", &CatchSwitch);
3531 
3532   for (BasicBlock *Handler : CatchSwitch.handlers()) {
3533     Assert(isa<CatchPadInst>(Handler->getFirstNonPHI()),
3534            "CatchSwitchInst handlers must be catchpads", &CatchSwitch, Handler);
3535   }
3536 
3537   visitEHPadPredecessors(CatchSwitch);
3538   visitTerminatorInst(CatchSwitch);
3539 }
3540 
visitCleanupReturnInst(CleanupReturnInst & CRI)3541 void Verifier::visitCleanupReturnInst(CleanupReturnInst &CRI) {
3542   Assert(isa<CleanupPadInst>(CRI.getOperand(0)),
3543          "CleanupReturnInst needs to be provided a CleanupPad", &CRI,
3544          CRI.getOperand(0));
3545 
3546   if (BasicBlock *UnwindDest = CRI.getUnwindDest()) {
3547     Instruction *I = UnwindDest->getFirstNonPHI();
3548     Assert(I->isEHPad() && !isa<LandingPadInst>(I),
3549            "CleanupReturnInst must unwind to an EH block which is not a "
3550            "landingpad.",
3551            &CRI);
3552   }
3553 
3554   visitTerminatorInst(CRI);
3555 }
3556 
verifyDominatesUse(Instruction & I,unsigned i)3557 void Verifier::verifyDominatesUse(Instruction &I, unsigned i) {
3558   Instruction *Op = cast<Instruction>(I.getOperand(i));
3559   // If the we have an invalid invoke, don't try to compute the dominance.
3560   // We already reject it in the invoke specific checks and the dominance
3561   // computation doesn't handle multiple edges.
3562   if (InvokeInst *II = dyn_cast<InvokeInst>(Op)) {
3563     if (II->getNormalDest() == II->getUnwindDest())
3564       return;
3565   }
3566 
3567   // Quick check whether the def has already been encountered in the same block.
3568   // PHI nodes are not checked to prevent accepting preceeding PHIs, because PHI
3569   // uses are defined to happen on the incoming edge, not at the instruction.
3570   //
3571   // FIXME: If this operand is a MetadataAsValue (wrapping a LocalAsMetadata)
3572   // wrapping an SSA value, assert that we've already encountered it.  See
3573   // related FIXME in Mapper::mapLocalAsMetadata in ValueMapper.cpp.
3574   if (!isa<PHINode>(I) && InstsInThisBlock.count(Op))
3575     return;
3576 
3577   const Use &U = I.getOperandUse(i);
3578   Assert(DT.dominates(Op, U),
3579          "Instruction does not dominate all uses!", Op, &I);
3580 }
3581 
visitDereferenceableMetadata(Instruction & I,MDNode * MD)3582 void Verifier::visitDereferenceableMetadata(Instruction& I, MDNode* MD) {
3583   Assert(I.getType()->isPointerTy(), "dereferenceable, dereferenceable_or_null "
3584          "apply only to pointer types", &I);
3585   Assert(isa<LoadInst>(I),
3586          "dereferenceable, dereferenceable_or_null apply only to load"
3587          " instructions, use attributes for calls or invokes", &I);
3588   Assert(MD->getNumOperands() == 1, "dereferenceable, dereferenceable_or_null "
3589          "take one operand!", &I);
3590   ConstantInt *CI = mdconst::dyn_extract<ConstantInt>(MD->getOperand(0));
3591   Assert(CI && CI->getType()->isIntegerTy(64), "dereferenceable, "
3592          "dereferenceable_or_null metadata value must be an i64!", &I);
3593 }
3594 
3595 /// verifyInstruction - Verify that an instruction is well formed.
3596 ///
visitInstruction(Instruction & I)3597 void Verifier::visitInstruction(Instruction &I) {
3598   BasicBlock *BB = I.getParent();
3599   Assert(BB, "Instruction not embedded in basic block!", &I);
3600 
3601   if (!isa<PHINode>(I)) {   // Check that non-phi nodes are not self referential
3602     for (User *U : I.users()) {
3603       Assert(U != (User *)&I || !DT.isReachableFromEntry(BB),
3604              "Only PHI nodes may reference their own value!", &I);
3605     }
3606   }
3607 
3608   // Check that void typed values don't have names
3609   Assert(!I.getType()->isVoidTy() || !I.hasName(),
3610          "Instruction has a name, but provides a void value!", &I);
3611 
3612   // Check that the return value of the instruction is either void or a legal
3613   // value type.
3614   Assert(I.getType()->isVoidTy() || I.getType()->isFirstClassType(),
3615          "Instruction returns a non-scalar type!", &I);
3616 
3617   // Check that the instruction doesn't produce metadata. Calls are already
3618   // checked against the callee type.
3619   Assert(!I.getType()->isMetadataTy() || isa<CallInst>(I) || isa<InvokeInst>(I),
3620          "Invalid use of metadata!", &I);
3621 
3622   // Check that all uses of the instruction, if they are instructions
3623   // themselves, actually have parent basic blocks.  If the use is not an
3624   // instruction, it is an error!
3625   for (Use &U : I.uses()) {
3626     if (Instruction *Used = dyn_cast<Instruction>(U.getUser()))
3627       Assert(Used->getParent() != nullptr,
3628              "Instruction referencing"
3629              " instruction not embedded in a basic block!",
3630              &I, Used);
3631     else {
3632       CheckFailed("Use of instruction is not an instruction!", U);
3633       return;
3634     }
3635   }
3636 
3637   for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i) {
3638     Assert(I.getOperand(i) != nullptr, "Instruction has null operand!", &I);
3639 
3640     // Check to make sure that only first-class-values are operands to
3641     // instructions.
3642     if (!I.getOperand(i)->getType()->isFirstClassType()) {
3643       Assert(0, "Instruction operands must be first-class values!", &I);
3644     }
3645 
3646     if (Function *F = dyn_cast<Function>(I.getOperand(i))) {
3647       // Check to make sure that the "address of" an intrinsic function is never
3648       // taken.
3649       Assert(
3650           !F->isIntrinsic() ||
3651               i == (isa<CallInst>(I) ? e - 1 : isa<InvokeInst>(I) ? e - 3 : 0),
3652           "Cannot take the address of an intrinsic!", &I);
3653       Assert(
3654           !F->isIntrinsic() || isa<CallInst>(I) ||
3655               F->getIntrinsicID() == Intrinsic::donothing ||
3656               F->getIntrinsicID() == Intrinsic::experimental_patchpoint_void ||
3657               F->getIntrinsicID() == Intrinsic::experimental_patchpoint_i64 ||
3658               F->getIntrinsicID() == Intrinsic::experimental_gc_statepoint,
3659           "Cannot invoke an intrinsic other than donothing, patchpoint or "
3660           "statepoint",
3661           &I);
3662       Assert(F->getParent() == M, "Referencing function in another module!",
3663              &I, M, F, F->getParent());
3664     } else if (BasicBlock *OpBB = dyn_cast<BasicBlock>(I.getOperand(i))) {
3665       Assert(OpBB->getParent() == BB->getParent(),
3666              "Referring to a basic block in another function!", &I);
3667     } else if (Argument *OpArg = dyn_cast<Argument>(I.getOperand(i))) {
3668       Assert(OpArg->getParent() == BB->getParent(),
3669              "Referring to an argument in another function!", &I);
3670     } else if (GlobalValue *GV = dyn_cast<GlobalValue>(I.getOperand(i))) {
3671       Assert(GV->getParent() == M, "Referencing global in another module!", &I, M, GV, GV->getParent());
3672     } else if (isa<Instruction>(I.getOperand(i))) {
3673       verifyDominatesUse(I, i);
3674     } else if (isa<InlineAsm>(I.getOperand(i))) {
3675       Assert((i + 1 == e && isa<CallInst>(I)) ||
3676                  (i + 3 == e && isa<InvokeInst>(I)),
3677              "Cannot take the address of an inline asm!", &I);
3678     } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(I.getOperand(i))) {
3679       if (CE->getType()->isPtrOrPtrVectorTy()) {
3680         // If we have a ConstantExpr pointer, we need to see if it came from an
3681         // illegal bitcast (inttoptr <constant int> )
3682         visitConstantExprsRecursively(CE);
3683       }
3684     }
3685   }
3686 
3687   if (MDNode *MD = I.getMetadata(LLVMContext::MD_fpmath)) {
3688     Assert(I.getType()->isFPOrFPVectorTy(),
3689            "fpmath requires a floating point result!", &I);
3690     Assert(MD->getNumOperands() == 1, "fpmath takes one operand!", &I);
3691     if (ConstantFP *CFP0 =
3692             mdconst::dyn_extract_or_null<ConstantFP>(MD->getOperand(0))) {
3693       const APFloat &Accuracy = CFP0->getValueAPF();
3694       Assert(&Accuracy.getSemantics() == &APFloat::IEEEsingle,
3695              "fpmath accuracy must have float type", &I);
3696       Assert(Accuracy.isFiniteNonZero() && !Accuracy.isNegative(),
3697              "fpmath accuracy not a positive number!", &I);
3698     } else {
3699       Assert(false, "invalid fpmath accuracy!", &I);
3700     }
3701   }
3702 
3703   if (MDNode *Range = I.getMetadata(LLVMContext::MD_range)) {
3704     Assert(isa<LoadInst>(I) || isa<CallInst>(I) || isa<InvokeInst>(I),
3705            "Ranges are only for loads, calls and invokes!", &I);
3706     visitRangeMetadata(I, Range, I.getType());
3707   }
3708 
3709   if (I.getMetadata(LLVMContext::MD_nonnull)) {
3710     Assert(I.getType()->isPointerTy(), "nonnull applies only to pointer types",
3711            &I);
3712     Assert(isa<LoadInst>(I),
3713            "nonnull applies only to load instructions, use attributes"
3714            " for calls or invokes",
3715            &I);
3716   }
3717 
3718   if (MDNode *MD = I.getMetadata(LLVMContext::MD_dereferenceable))
3719     visitDereferenceableMetadata(I, MD);
3720 
3721   if (MDNode *MD = I.getMetadata(LLVMContext::MD_dereferenceable_or_null))
3722     visitDereferenceableMetadata(I, MD);
3723 
3724   if (MDNode *AlignMD = I.getMetadata(LLVMContext::MD_align)) {
3725     Assert(I.getType()->isPointerTy(), "align applies only to pointer types",
3726            &I);
3727     Assert(isa<LoadInst>(I), "align applies only to load instructions, "
3728            "use attributes for calls or invokes", &I);
3729     Assert(AlignMD->getNumOperands() == 1, "align takes one operand!", &I);
3730     ConstantInt *CI = mdconst::dyn_extract<ConstantInt>(AlignMD->getOperand(0));
3731     Assert(CI && CI->getType()->isIntegerTy(64),
3732            "align metadata value must be an i64!", &I);
3733     uint64_t Align = CI->getZExtValue();
3734     Assert(isPowerOf2_64(Align),
3735            "align metadata value must be a power of 2!", &I);
3736     Assert(Align <= Value::MaximumAlignment,
3737            "alignment is larger that implementation defined limit", &I);
3738   }
3739 
3740   if (MDNode *N = I.getDebugLoc().getAsMDNode()) {
3741     AssertDI(isa<DILocation>(N), "invalid !dbg metadata attachment", &I, N);
3742     visitMDNode(*N);
3743   }
3744 
3745   if (auto *DII = dyn_cast<DbgInfoIntrinsic>(&I))
3746     verifyBitPieceExpression(*DII);
3747 
3748   InstsInThisBlock.insert(&I);
3749 }
3750 
3751 /// Allow intrinsics to be verified in different ways.
visitIntrinsicCallSite(Intrinsic::ID ID,CallSite CS)3752 void Verifier::visitIntrinsicCallSite(Intrinsic::ID ID, CallSite CS) {
3753   Function *IF = CS.getCalledFunction();
3754   Assert(IF->isDeclaration(), "Intrinsic functions should never be defined!",
3755          IF);
3756 
3757   // Verify that the intrinsic prototype lines up with what the .td files
3758   // describe.
3759   FunctionType *IFTy = IF->getFunctionType();
3760   bool IsVarArg = IFTy->isVarArg();
3761 
3762   SmallVector<Intrinsic::IITDescriptor, 8> Table;
3763   getIntrinsicInfoTableEntries(ID, Table);
3764   ArrayRef<Intrinsic::IITDescriptor> TableRef = Table;
3765 
3766   SmallVector<Type *, 4> ArgTys;
3767   Assert(!Intrinsic::matchIntrinsicType(IFTy->getReturnType(),
3768                                         TableRef, ArgTys),
3769          "Intrinsic has incorrect return type!", IF);
3770   for (unsigned i = 0, e = IFTy->getNumParams(); i != e; ++i)
3771     Assert(!Intrinsic::matchIntrinsicType(IFTy->getParamType(i),
3772                                           TableRef, ArgTys),
3773            "Intrinsic has incorrect argument type!", IF);
3774 
3775   // Verify if the intrinsic call matches the vararg property.
3776   if (IsVarArg)
3777     Assert(!Intrinsic::matchIntrinsicVarArg(IsVarArg, TableRef),
3778            "Intrinsic was not defined with variable arguments!", IF);
3779   else
3780     Assert(!Intrinsic::matchIntrinsicVarArg(IsVarArg, TableRef),
3781            "Callsite was not defined with variable arguments!", IF);
3782 
3783   // All descriptors should be absorbed by now.
3784   Assert(TableRef.empty(), "Intrinsic has too few arguments!", IF);
3785 
3786   // Now that we have the intrinsic ID and the actual argument types (and we
3787   // know they are legal for the intrinsic!) get the intrinsic name through the
3788   // usual means.  This allows us to verify the mangling of argument types into
3789   // the name.
3790   const std::string ExpectedName = Intrinsic::getName(ID, ArgTys);
3791   Assert(ExpectedName == IF->getName(),
3792          "Intrinsic name not mangled correctly for type arguments! "
3793          "Should be: " +
3794              ExpectedName,
3795          IF);
3796 
3797   // If the intrinsic takes MDNode arguments, verify that they are either global
3798   // or are local to *this* function.
3799   for (Value *V : CS.args())
3800     if (auto *MD = dyn_cast<MetadataAsValue>(V))
3801       visitMetadataAsValue(*MD, CS.getCaller());
3802 
3803   switch (ID) {
3804   default:
3805     break;
3806   case Intrinsic::ctlz:  // llvm.ctlz
3807   case Intrinsic::cttz:  // llvm.cttz
3808     Assert(isa<ConstantInt>(CS.getArgOperand(1)),
3809            "is_zero_undef argument of bit counting intrinsics must be a "
3810            "constant int",
3811            CS);
3812     break;
3813   case Intrinsic::dbg_declare: // llvm.dbg.declare
3814     Assert(isa<MetadataAsValue>(CS.getArgOperand(0)),
3815            "invalid llvm.dbg.declare intrinsic call 1", CS);
3816     visitDbgIntrinsic("declare", cast<DbgDeclareInst>(*CS.getInstruction()));
3817     break;
3818   case Intrinsic::dbg_value: // llvm.dbg.value
3819     visitDbgIntrinsic("value", cast<DbgValueInst>(*CS.getInstruction()));
3820     break;
3821   case Intrinsic::memcpy:
3822   case Intrinsic::memmove:
3823   case Intrinsic::memset: {
3824     ConstantInt *AlignCI = dyn_cast<ConstantInt>(CS.getArgOperand(3));
3825     Assert(AlignCI,
3826            "alignment argument of memory intrinsics must be a constant int",
3827            CS);
3828     const APInt &AlignVal = AlignCI->getValue();
3829     Assert(AlignCI->isZero() || AlignVal.isPowerOf2(),
3830            "alignment argument of memory intrinsics must be a power of 2", CS);
3831     Assert(isa<ConstantInt>(CS.getArgOperand(4)),
3832            "isvolatile argument of memory intrinsics must be a constant int",
3833            CS);
3834     break;
3835   }
3836   case Intrinsic::gcroot:
3837   case Intrinsic::gcwrite:
3838   case Intrinsic::gcread:
3839     if (ID == Intrinsic::gcroot) {
3840       AllocaInst *AI =
3841         dyn_cast<AllocaInst>(CS.getArgOperand(0)->stripPointerCasts());
3842       Assert(AI, "llvm.gcroot parameter #1 must be an alloca.", CS);
3843       Assert(isa<Constant>(CS.getArgOperand(1)),
3844              "llvm.gcroot parameter #2 must be a constant.", CS);
3845       if (!AI->getAllocatedType()->isPointerTy()) {
3846         Assert(!isa<ConstantPointerNull>(CS.getArgOperand(1)),
3847                "llvm.gcroot parameter #1 must either be a pointer alloca, "
3848                "or argument #2 must be a non-null constant.",
3849                CS);
3850       }
3851     }
3852 
3853     Assert(CS.getParent()->getParent()->hasGC(),
3854            "Enclosing function does not use GC.", CS);
3855     break;
3856   case Intrinsic::init_trampoline:
3857     Assert(isa<Function>(CS.getArgOperand(1)->stripPointerCasts()),
3858            "llvm.init_trampoline parameter #2 must resolve to a function.",
3859            CS);
3860     break;
3861   case Intrinsic::prefetch:
3862     Assert(isa<ConstantInt>(CS.getArgOperand(1)) &&
3863                isa<ConstantInt>(CS.getArgOperand(2)) &&
3864                cast<ConstantInt>(CS.getArgOperand(1))->getZExtValue() < 2 &&
3865                cast<ConstantInt>(CS.getArgOperand(2))->getZExtValue() < 4,
3866            "invalid arguments to llvm.prefetch", CS);
3867     break;
3868   case Intrinsic::stackprotector:
3869     Assert(isa<AllocaInst>(CS.getArgOperand(1)->stripPointerCasts()),
3870            "llvm.stackprotector parameter #2 must resolve to an alloca.", CS);
3871     break;
3872   case Intrinsic::lifetime_start:
3873   case Intrinsic::lifetime_end:
3874   case Intrinsic::invariant_start:
3875     Assert(isa<ConstantInt>(CS.getArgOperand(0)),
3876            "size argument of memory use markers must be a constant integer",
3877            CS);
3878     break;
3879   case Intrinsic::invariant_end:
3880     Assert(isa<ConstantInt>(CS.getArgOperand(1)),
3881            "llvm.invariant.end parameter #2 must be a constant integer", CS);
3882     break;
3883 
3884   case Intrinsic::localescape: {
3885     BasicBlock *BB = CS.getParent();
3886     Assert(BB == &BB->getParent()->front(),
3887            "llvm.localescape used outside of entry block", CS);
3888     Assert(!SawFrameEscape,
3889            "multiple calls to llvm.localescape in one function", CS);
3890     for (Value *Arg : CS.args()) {
3891       if (isa<ConstantPointerNull>(Arg))
3892         continue; // Null values are allowed as placeholders.
3893       auto *AI = dyn_cast<AllocaInst>(Arg->stripPointerCasts());
3894       Assert(AI && AI->isStaticAlloca(),
3895              "llvm.localescape only accepts static allocas", CS);
3896     }
3897     FrameEscapeInfo[BB->getParent()].first = CS.getNumArgOperands();
3898     SawFrameEscape = true;
3899     break;
3900   }
3901   case Intrinsic::localrecover: {
3902     Value *FnArg = CS.getArgOperand(0)->stripPointerCasts();
3903     Function *Fn = dyn_cast<Function>(FnArg);
3904     Assert(Fn && !Fn->isDeclaration(),
3905            "llvm.localrecover first "
3906            "argument must be function defined in this module",
3907            CS);
3908     auto *IdxArg = dyn_cast<ConstantInt>(CS.getArgOperand(2));
3909     Assert(IdxArg, "idx argument of llvm.localrecover must be a constant int",
3910            CS);
3911     auto &Entry = FrameEscapeInfo[Fn];
3912     Entry.second = unsigned(
3913         std::max(uint64_t(Entry.second), IdxArg->getLimitedValue(~0U) + 1));
3914     break;
3915   }
3916 
3917   case Intrinsic::experimental_gc_statepoint:
3918     Assert(!CS.isInlineAsm(),
3919            "gc.statepoint support for inline assembly unimplemented", CS);
3920     Assert(CS.getParent()->getParent()->hasGC(),
3921            "Enclosing function does not use GC.", CS);
3922 
3923     verifyStatepoint(CS);
3924     break;
3925   case Intrinsic::experimental_gc_result: {
3926     Assert(CS.getParent()->getParent()->hasGC(),
3927            "Enclosing function does not use GC.", CS);
3928     // Are we tied to a statepoint properly?
3929     CallSite StatepointCS(CS.getArgOperand(0));
3930     const Function *StatepointFn =
3931       StatepointCS.getInstruction() ? StatepointCS.getCalledFunction() : nullptr;
3932     Assert(StatepointFn && StatepointFn->isDeclaration() &&
3933                StatepointFn->getIntrinsicID() ==
3934                    Intrinsic::experimental_gc_statepoint,
3935            "gc.result operand #1 must be from a statepoint", CS,
3936            CS.getArgOperand(0));
3937 
3938     // Assert that result type matches wrapped callee.
3939     const Value *Target = StatepointCS.getArgument(2);
3940     auto *PT = cast<PointerType>(Target->getType());
3941     auto *TargetFuncType = cast<FunctionType>(PT->getElementType());
3942     Assert(CS.getType() == TargetFuncType->getReturnType(),
3943            "gc.result result type does not match wrapped callee", CS);
3944     break;
3945   }
3946   case Intrinsic::experimental_gc_relocate: {
3947     Assert(CS.getNumArgOperands() == 3, "wrong number of arguments", CS);
3948 
3949     Assert(isa<PointerType>(CS.getType()->getScalarType()),
3950            "gc.relocate must return a pointer or a vector of pointers", CS);
3951 
3952     // Check that this relocate is correctly tied to the statepoint
3953 
3954     // This is case for relocate on the unwinding path of an invoke statepoint
3955     if (LandingPadInst *LandingPad =
3956           dyn_cast<LandingPadInst>(CS.getArgOperand(0))) {
3957 
3958       const BasicBlock *InvokeBB =
3959           LandingPad->getParent()->getUniquePredecessor();
3960 
3961       // Landingpad relocates should have only one predecessor with invoke
3962       // statepoint terminator
3963       Assert(InvokeBB, "safepoints should have unique landingpads",
3964              LandingPad->getParent());
3965       Assert(InvokeBB->getTerminator(), "safepoint block should be well formed",
3966              InvokeBB);
3967       Assert(isStatepoint(InvokeBB->getTerminator()),
3968              "gc relocate should be linked to a statepoint", InvokeBB);
3969     }
3970     else {
3971       // In all other cases relocate should be tied to the statepoint directly.
3972       // This covers relocates on a normal return path of invoke statepoint and
3973       // relocates of a call statepoint.
3974       auto Token = CS.getArgOperand(0);
3975       Assert(isa<Instruction>(Token) && isStatepoint(cast<Instruction>(Token)),
3976              "gc relocate is incorrectly tied to the statepoint", CS, Token);
3977     }
3978 
3979     // Verify rest of the relocate arguments.
3980 
3981     ImmutableCallSite StatepointCS(
3982         cast<GCRelocateInst>(*CS.getInstruction()).getStatepoint());
3983 
3984     // Both the base and derived must be piped through the safepoint.
3985     Value* Base = CS.getArgOperand(1);
3986     Assert(isa<ConstantInt>(Base),
3987            "gc.relocate operand #2 must be integer offset", CS);
3988 
3989     Value* Derived = CS.getArgOperand(2);
3990     Assert(isa<ConstantInt>(Derived),
3991            "gc.relocate operand #3 must be integer offset", CS);
3992 
3993     const int BaseIndex = cast<ConstantInt>(Base)->getZExtValue();
3994     const int DerivedIndex = cast<ConstantInt>(Derived)->getZExtValue();
3995     // Check the bounds
3996     Assert(0 <= BaseIndex && BaseIndex < (int)StatepointCS.arg_size(),
3997            "gc.relocate: statepoint base index out of bounds", CS);
3998     Assert(0 <= DerivedIndex && DerivedIndex < (int)StatepointCS.arg_size(),
3999            "gc.relocate: statepoint derived index out of bounds", CS);
4000 
4001     // Check that BaseIndex and DerivedIndex fall within the 'gc parameters'
4002     // section of the statepoint's argument.
4003     Assert(StatepointCS.arg_size() > 0,
4004            "gc.statepoint: insufficient arguments");
4005     Assert(isa<ConstantInt>(StatepointCS.getArgument(3)),
4006            "gc.statement: number of call arguments must be constant integer");
4007     const unsigned NumCallArgs =
4008         cast<ConstantInt>(StatepointCS.getArgument(3))->getZExtValue();
4009     Assert(StatepointCS.arg_size() > NumCallArgs + 5,
4010            "gc.statepoint: mismatch in number of call arguments");
4011     Assert(isa<ConstantInt>(StatepointCS.getArgument(NumCallArgs + 5)),
4012            "gc.statepoint: number of transition arguments must be "
4013            "a constant integer");
4014     const int NumTransitionArgs =
4015         cast<ConstantInt>(StatepointCS.getArgument(NumCallArgs + 5))
4016             ->getZExtValue();
4017     const int DeoptArgsStart = 4 + NumCallArgs + 1 + NumTransitionArgs + 1;
4018     Assert(isa<ConstantInt>(StatepointCS.getArgument(DeoptArgsStart)),
4019            "gc.statepoint: number of deoptimization arguments must be "
4020            "a constant integer");
4021     const int NumDeoptArgs =
4022         cast<ConstantInt>(StatepointCS.getArgument(DeoptArgsStart))
4023             ->getZExtValue();
4024     const int GCParamArgsStart = DeoptArgsStart + 1 + NumDeoptArgs;
4025     const int GCParamArgsEnd = StatepointCS.arg_size();
4026     Assert(GCParamArgsStart <= BaseIndex && BaseIndex < GCParamArgsEnd,
4027            "gc.relocate: statepoint base index doesn't fall within the "
4028            "'gc parameters' section of the statepoint call",
4029            CS);
4030     Assert(GCParamArgsStart <= DerivedIndex && DerivedIndex < GCParamArgsEnd,
4031            "gc.relocate: statepoint derived index doesn't fall within the "
4032            "'gc parameters' section of the statepoint call",
4033            CS);
4034 
4035     // Relocated value must be either a pointer type or vector-of-pointer type,
4036     // but gc_relocate does not need to return the same pointer type as the
4037     // relocated pointer. It can be casted to the correct type later if it's
4038     // desired. However, they must have the same address space and 'vectorness'
4039     GCRelocateInst &Relocate = cast<GCRelocateInst>(*CS.getInstruction());
4040     Assert(Relocate.getDerivedPtr()->getType()->getScalarType()->isPointerTy(),
4041            "gc.relocate: relocated value must be a gc pointer", CS);
4042 
4043     auto ResultType = CS.getType();
4044     auto DerivedType = Relocate.getDerivedPtr()->getType();
4045     Assert(ResultType->isVectorTy() == DerivedType->isVectorTy(),
4046            "gc.relocate: vector relocates to vector and pointer to pointer",
4047            CS);
4048     Assert(
4049         ResultType->getPointerAddressSpace() ==
4050             DerivedType->getPointerAddressSpace(),
4051         "gc.relocate: relocating a pointer shouldn't change its address space",
4052         CS);
4053     break;
4054   }
4055   case Intrinsic::eh_exceptioncode:
4056   case Intrinsic::eh_exceptionpointer: {
4057     Assert(isa<CatchPadInst>(CS.getArgOperand(0)),
4058            "eh.exceptionpointer argument must be a catchpad", CS);
4059     break;
4060   }
4061   case Intrinsic::masked_load: {
4062     Assert(CS.getType()->isVectorTy(), "masked_load: must return a vector", CS);
4063 
4064     Value *Ptr = CS.getArgOperand(0);
4065     //Value *Alignment = CS.getArgOperand(1);
4066     Value *Mask = CS.getArgOperand(2);
4067     Value *PassThru = CS.getArgOperand(3);
4068     Assert(Mask->getType()->isVectorTy(),
4069            "masked_load: mask must be vector", CS);
4070 
4071     // DataTy is the overloaded type
4072     Type *DataTy = cast<PointerType>(Ptr->getType())->getElementType();
4073     Assert(DataTy == CS.getType(),
4074            "masked_load: return must match pointer type", CS);
4075     Assert(PassThru->getType() == DataTy,
4076            "masked_load: pass through and data type must match", CS);
4077     Assert(Mask->getType()->getVectorNumElements() ==
4078            DataTy->getVectorNumElements(),
4079            "masked_load: vector mask must be same length as data", CS);
4080     break;
4081   }
4082   case Intrinsic::masked_store: {
4083     Value *Val = CS.getArgOperand(0);
4084     Value *Ptr = CS.getArgOperand(1);
4085     //Value *Alignment = CS.getArgOperand(2);
4086     Value *Mask = CS.getArgOperand(3);
4087     Assert(Mask->getType()->isVectorTy(),
4088            "masked_store: mask must be vector", CS);
4089 
4090     // DataTy is the overloaded type
4091     Type *DataTy = cast<PointerType>(Ptr->getType())->getElementType();
4092     Assert(DataTy == Val->getType(),
4093            "masked_store: storee must match pointer type", CS);
4094     Assert(Mask->getType()->getVectorNumElements() ==
4095            DataTy->getVectorNumElements(),
4096            "masked_store: vector mask must be same length as data", CS);
4097     break;
4098   }
4099 
4100   case Intrinsic::experimental_guard: {
4101     Assert(CS.isCall(), "experimental_guard cannot be invoked", CS);
4102     Assert(CS.countOperandBundlesOfType(LLVMContext::OB_deopt) == 1,
4103            "experimental_guard must have exactly one "
4104            "\"deopt\" operand bundle");
4105     break;
4106   }
4107 
4108   case Intrinsic::experimental_deoptimize: {
4109     Assert(CS.isCall(), "experimental_deoptimize cannot be invoked", CS);
4110     Assert(CS.countOperandBundlesOfType(LLVMContext::OB_deopt) == 1,
4111            "experimental_deoptimize must have exactly one "
4112            "\"deopt\" operand bundle");
4113     Assert(CS.getType() == CS.getInstruction()->getFunction()->getReturnType(),
4114            "experimental_deoptimize return type must match caller return type");
4115 
4116     if (CS.isCall()) {
4117       auto *DeoptCI = CS.getInstruction();
4118       auto *RI = dyn_cast<ReturnInst>(DeoptCI->getNextNode());
4119       Assert(RI,
4120              "calls to experimental_deoptimize must be followed by a return");
4121 
4122       if (!CS.getType()->isVoidTy() && RI)
4123         Assert(RI->getReturnValue() == DeoptCI,
4124                "calls to experimental_deoptimize must be followed by a return "
4125                "of the value computed by experimental_deoptimize");
4126     }
4127 
4128     break;
4129   }
4130   };
4131 }
4132 
4133 /// \brief Carefully grab the subprogram from a local scope.
4134 ///
4135 /// This carefully grabs the subprogram from a local scope, avoiding the
4136 /// built-in assertions that would typically fire.
getSubprogram(Metadata * LocalScope)4137 static DISubprogram *getSubprogram(Metadata *LocalScope) {
4138   if (!LocalScope)
4139     return nullptr;
4140 
4141   if (auto *SP = dyn_cast<DISubprogram>(LocalScope))
4142     return SP;
4143 
4144   if (auto *LB = dyn_cast<DILexicalBlockBase>(LocalScope))
4145     return getSubprogram(LB->getRawScope());
4146 
4147   // Just return null; broken scope chains are checked elsewhere.
4148   assert(!isa<DILocalScope>(LocalScope) && "Unknown type of local scope");
4149   return nullptr;
4150 }
4151 
4152 template <class DbgIntrinsicTy>
visitDbgIntrinsic(StringRef Kind,DbgIntrinsicTy & DII)4153 void Verifier::visitDbgIntrinsic(StringRef Kind, DbgIntrinsicTy &DII) {
4154   auto *MD = cast<MetadataAsValue>(DII.getArgOperand(0))->getMetadata();
4155   AssertDI(isa<ValueAsMetadata>(MD) ||
4156              (isa<MDNode>(MD) && !cast<MDNode>(MD)->getNumOperands()),
4157          "invalid llvm.dbg." + Kind + " intrinsic address/value", &DII, MD);
4158   AssertDI(isa<DILocalVariable>(DII.getRawVariable()),
4159          "invalid llvm.dbg." + Kind + " intrinsic variable", &DII,
4160          DII.getRawVariable());
4161   AssertDI(isa<DIExpression>(DII.getRawExpression()),
4162          "invalid llvm.dbg." + Kind + " intrinsic expression", &DII,
4163          DII.getRawExpression());
4164 
4165   // Ignore broken !dbg attachments; they're checked elsewhere.
4166   if (MDNode *N = DII.getDebugLoc().getAsMDNode())
4167     if (!isa<DILocation>(N))
4168       return;
4169 
4170   BasicBlock *BB = DII.getParent();
4171   Function *F = BB ? BB->getParent() : nullptr;
4172 
4173   // The scopes for variables and !dbg attachments must agree.
4174   DILocalVariable *Var = DII.getVariable();
4175   DILocation *Loc = DII.getDebugLoc();
4176   Assert(Loc, "llvm.dbg." + Kind + " intrinsic requires a !dbg attachment",
4177          &DII, BB, F);
4178 
4179   DISubprogram *VarSP = getSubprogram(Var->getRawScope());
4180   DISubprogram *LocSP = getSubprogram(Loc->getRawScope());
4181   if (!VarSP || !LocSP)
4182     return; // Broken scope chains are checked elsewhere.
4183 
4184   Assert(VarSP == LocSP, "mismatched subprogram between llvm.dbg." + Kind +
4185                              " variable and !dbg attachment",
4186          &DII, BB, F, Var, Var->getScope()->getSubprogram(), Loc,
4187          Loc->getScope()->getSubprogram());
4188 }
4189 
getVariableSize(const DILocalVariable & V)4190 static uint64_t getVariableSize(const DILocalVariable &V) {
4191   // Be careful of broken types (checked elsewhere).
4192   const Metadata *RawType = V.getRawType();
4193   while (RawType) {
4194     // Try to get the size directly.
4195     if (auto *T = dyn_cast<DIType>(RawType))
4196       if (uint64_t Size = T->getSizeInBits())
4197         return Size;
4198 
4199     if (auto *DT = dyn_cast<DIDerivedType>(RawType)) {
4200       // Look at the base type.
4201       RawType = DT->getRawBaseType();
4202       continue;
4203     }
4204 
4205     // Missing type or size.
4206     break;
4207   }
4208 
4209   // Fail gracefully.
4210   return 0;
4211 }
4212 
verifyBitPieceExpression(const DbgInfoIntrinsic & I)4213 void Verifier::verifyBitPieceExpression(const DbgInfoIntrinsic &I) {
4214   DILocalVariable *V;
4215   DIExpression *E;
4216   if (auto *DVI = dyn_cast<DbgValueInst>(&I)) {
4217     V = dyn_cast_or_null<DILocalVariable>(DVI->getRawVariable());
4218     E = dyn_cast_or_null<DIExpression>(DVI->getRawExpression());
4219   } else {
4220     auto *DDI = cast<DbgDeclareInst>(&I);
4221     V = dyn_cast_or_null<DILocalVariable>(DDI->getRawVariable());
4222     E = dyn_cast_or_null<DIExpression>(DDI->getRawExpression());
4223   }
4224 
4225   // We don't know whether this intrinsic verified correctly.
4226   if (!V || !E || !E->isValid())
4227     return;
4228 
4229   // Nothing to do if this isn't a bit piece expression.
4230   if (!E->isBitPiece())
4231     return;
4232 
4233   // The frontend helps out GDB by emitting the members of local anonymous
4234   // unions as artificial local variables with shared storage. When SROA splits
4235   // the storage for artificial local variables that are smaller than the entire
4236   // union, the overhang piece will be outside of the allotted space for the
4237   // variable and this check fails.
4238   // FIXME: Remove this check as soon as clang stops doing this; it hides bugs.
4239   if (V->isArtificial())
4240     return;
4241 
4242   // If there's no size, the type is broken, but that should be checked
4243   // elsewhere.
4244   uint64_t VarSize = getVariableSize(*V);
4245   if (!VarSize)
4246     return;
4247 
4248   unsigned PieceSize = E->getBitPieceSize();
4249   unsigned PieceOffset = E->getBitPieceOffset();
4250   Assert(PieceSize + PieceOffset <= VarSize,
4251          "piece is larger than or outside of variable", &I, V, E);
4252   Assert(PieceSize != VarSize, "piece covers entire variable", &I, V, E);
4253 }
4254 
verifyCompileUnits()4255 void Verifier::verifyCompileUnits() {
4256   auto *CUs = M->getNamedMetadata("llvm.dbg.cu");
4257   SmallPtrSet<const Metadata *, 2> Listed;
4258   if (CUs)
4259     Listed.insert(CUs->op_begin(), CUs->op_end());
4260   Assert(
4261       std::all_of(CUVisited.begin(), CUVisited.end(),
4262                   [&Listed](const Metadata *CU) { return Listed.count(CU); }),
4263       "All DICompileUnits must be listed in llvm.dbg.cu");
4264   CUVisited.clear();
4265 }
4266 
verifyDeoptimizeCallingConvs()4267 void Verifier::verifyDeoptimizeCallingConvs() {
4268   if (DeoptimizeDeclarations.empty())
4269     return;
4270 
4271   const Function *First = DeoptimizeDeclarations[0];
4272   for (auto *F : makeArrayRef(DeoptimizeDeclarations).slice(1)) {
4273     Assert(First->getCallingConv() == F->getCallingConv(),
4274            "All llvm.experimental.deoptimize declarations must have the same "
4275            "calling convention",
4276            First, F);
4277   }
4278 }
4279 
4280 //===----------------------------------------------------------------------===//
4281 //  Implement the public interfaces to this file...
4282 //===----------------------------------------------------------------------===//
4283 
verifyFunction(const Function & f,raw_ostream * OS)4284 bool llvm::verifyFunction(const Function &f, raw_ostream *OS) {
4285   Function &F = const_cast<Function &>(f);
4286 
4287   // Don't use a raw_null_ostream.  Printing IR is expensive.
4288   Verifier V(OS, /*ShouldTreatBrokenDebugInfoAsError=*/true);
4289 
4290   // Note that this function's return value is inverted from what you would
4291   // expect of a function called "verify".
4292   return !V.verify(F);
4293 }
4294 
verifyModule(const Module & M,raw_ostream * OS,bool * BrokenDebugInfo)4295 bool llvm::verifyModule(const Module &M, raw_ostream *OS,
4296                         bool *BrokenDebugInfo) {
4297   // Don't use a raw_null_ostream.  Printing IR is expensive.
4298   Verifier V(OS, /*ShouldTreatBrokenDebugInfoAsError=*/!BrokenDebugInfo);
4299 
4300   bool Broken = false;
4301   for (const Function &F : M)
4302     Broken |= !V.verify(F);
4303 
4304   Broken |= !V.verify(M);
4305   if (BrokenDebugInfo)
4306     *BrokenDebugInfo = V.hasBrokenDebugInfo();
4307   // Note that this function's return value is inverted from what you would
4308   // expect of a function called "verify".
4309   return Broken;
4310 }
4311 
4312 namespace {
4313 struct VerifierLegacyPass : public FunctionPass {
4314   static char ID;
4315 
4316   Verifier V;
4317   bool FatalErrors = true;
4318 
VerifierLegacyPass__anon51203d770511::VerifierLegacyPass4319   VerifierLegacyPass()
4320       : FunctionPass(ID),
4321         V(&dbgs(), /*ShouldTreatBrokenDebugInfoAsError=*/false) {
4322     initializeVerifierLegacyPassPass(*PassRegistry::getPassRegistry());
4323   }
VerifierLegacyPass__anon51203d770511::VerifierLegacyPass4324   explicit VerifierLegacyPass(bool FatalErrors)
4325       : FunctionPass(ID),
4326         V(&dbgs(), /*ShouldTreatBrokenDebugInfoAsError=*/false),
4327         FatalErrors(FatalErrors) {
4328     initializeVerifierLegacyPassPass(*PassRegistry::getPassRegistry());
4329   }
4330 
runOnFunction__anon51203d770511::VerifierLegacyPass4331   bool runOnFunction(Function &F) override {
4332     if (!V.verify(F) && FatalErrors)
4333       report_fatal_error("Broken function found, compilation aborted!");
4334 
4335     return false;
4336   }
4337 
doFinalization__anon51203d770511::VerifierLegacyPass4338   bool doFinalization(Module &M) override {
4339     bool HasErrors = false;
4340     for (Function &F : M)
4341       if (F.isDeclaration())
4342         HasErrors |= !V.verify(F);
4343 
4344     HasErrors |= !V.verify(M);
4345     if (FatalErrors) {
4346       if (HasErrors)
4347         report_fatal_error("Broken module found, compilation aborted!");
4348       assert(!V.hasBrokenDebugInfo() && "Module contains invalid debug info");
4349     }
4350 
4351     // Strip broken debug info.
4352     if (V.hasBrokenDebugInfo()) {
4353       DiagnosticInfoIgnoringInvalidDebugMetadata DiagInvalid(M);
4354       M.getContext().diagnose(DiagInvalid);
4355       if (!StripDebugInfo(M))
4356         report_fatal_error("Failed to strip malformed debug info");
4357     }
4358     return false;
4359   }
4360 
getAnalysisUsage__anon51203d770511::VerifierLegacyPass4361   void getAnalysisUsage(AnalysisUsage &AU) const override {
4362     AU.setPreservesAll();
4363   }
4364 };
4365 }
4366 
4367 char VerifierLegacyPass::ID = 0;
4368 INITIALIZE_PASS(VerifierLegacyPass, "verify", "Module Verifier", false, false)
4369 
createVerifierPass(bool FatalErrors)4370 FunctionPass *llvm::createVerifierPass(bool FatalErrors) {
4371   return new VerifierLegacyPass(FatalErrors);
4372 }
4373 
4374 char VerifierAnalysis::PassID;
run(Module & M,ModuleAnalysisManager &)4375 VerifierAnalysis::Result VerifierAnalysis::run(Module &M,
4376                                                ModuleAnalysisManager &) {
4377   Result Res;
4378   Res.IRBroken = llvm::verifyModule(M, &dbgs(), &Res.DebugInfoBroken);
4379   return Res;
4380 }
4381 
run(Function & F,FunctionAnalysisManager &)4382 VerifierAnalysis::Result VerifierAnalysis::run(Function &F,
4383                                                FunctionAnalysisManager &) {
4384   return { llvm::verifyFunction(F, &dbgs()), false };
4385 }
4386 
run(Module & M,ModuleAnalysisManager & AM)4387 PreservedAnalyses VerifierPass::run(Module &M, ModuleAnalysisManager &AM) {
4388   auto Res = AM.getResult<VerifierAnalysis>(M);
4389   if (FatalErrors) {
4390     if (Res.IRBroken)
4391       report_fatal_error("Broken module found, compilation aborted!");
4392     assert(!Res.DebugInfoBroken && "Module contains invalid debug info");
4393   }
4394 
4395   // Strip broken debug info.
4396   if (Res.DebugInfoBroken) {
4397     DiagnosticInfoIgnoringInvalidDebugMetadata DiagInvalid(M);
4398     M.getContext().diagnose(DiagInvalid);
4399     if (!StripDebugInfo(M))
4400       report_fatal_error("Failed to strip malformed debug info");
4401   }
4402   return PreservedAnalyses::all();
4403 }
4404 
run(Function & F,FunctionAnalysisManager & AM)4405 PreservedAnalyses VerifierPass::run(Function &F, FunctionAnalysisManager &AM) {
4406   auto res = AM.getResult<VerifierAnalysis>(F);
4407   if (res.IRBroken && FatalErrors)
4408     report_fatal_error("Broken function found, compilation aborted!");
4409 
4410   return PreservedAnalyses::all();
4411 }
4412