| // CFRefCount.cpp - Transfer functions for tracking simple values -*- C++ -*--// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines the methods for CFRefCount, which implements |
| // a reference count checker for Core Foundation (Mac OS X). |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "GRSimpleVals.h" |
| #include "clang/Basic/LangOptions.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "clang/Analysis/PathSensitive/GRExprEngineBuilders.h" |
| #include "clang/Analysis/PathSensitive/GRStateTrait.h" |
| #include "clang/Analysis/PathDiagnostic.h" |
| #include "clang/Analysis/LocalCheckers.h" |
| #include "clang/Analysis/PathDiagnostic.h" |
| #include "clang/Analysis/PathSensitive/BugReporter.h" |
| #include "clang/Analysis/PathSensitive/SymbolManager.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/FoldingSet.h" |
| #include "llvm/ADT/ImmutableMap.h" |
| #include "llvm/ADT/ImmutableList.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "llvm/Support/Compiler.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include <ostream> |
| #include <stdarg.h> |
| |
| using namespace clang; |
| |
| //===----------------------------------------------------------------------===// |
| // Utility functions. |
| //===----------------------------------------------------------------------===// |
| |
| // The "fundamental rule" for naming conventions of methods: |
| // (url broken into two lines) |
| // http://developer.apple.com/documentation/Cocoa/Conceptual/ |
| // MemoryMgmt/Tasks/MemoryManagementRules.html |
| // |
| // "You take ownership of an object if you create it using a method whose name |
| // begins with “alloc” or “new” or contains “copy” (for example, alloc, |
| // newObject, or mutableCopy), or if you send it a retain message. You are |
| // responsible for relinquishing ownership of objects you own using release |
| // or autorelease. Any other time you receive an object, you must |
| // not release it." |
| // |
| |
| using llvm::CStrInCStrNoCase; |
| using llvm::StringsEqualNoCase; |
| |
| enum NamingConvention { NoConvention, CreateRule, InitRule }; |
| |
| static inline bool isWordEnd(char ch, char prev, char next) { |
| return ch == '\0' |
| || (islower(prev) && isupper(ch)) // xxxC |
| || (isupper(prev) && isupper(ch) && islower(next)) // XXCreate |
| || !isalpha(ch); |
| } |
| |
| static inline const char* parseWord(const char* s) { |
| char ch = *s, prev = '\0'; |
| assert(ch != '\0'); |
| char next = *(s+1); |
| while (!isWordEnd(ch, prev, next)) { |
| prev = ch; |
| ch = next; |
| next = *((++s)+1); |
| } |
| return s; |
| } |
| |
| static NamingConvention deriveNamingConvention(const char* s) { |
| // A method/function name may contain a prefix. We don't know it is there, |
| // however, until we encounter the first '_'. |
| bool InPossiblePrefix = true; |
| bool AtBeginning = true; |
| NamingConvention C = NoConvention; |
| |
| while (*s != '\0') { |
| // Skip '_'. |
| if (*s == '_') { |
| if (InPossiblePrefix) { |
| InPossiblePrefix = false; |
| AtBeginning = true; |
| // Discard whatever 'convention' we |
| // had already derived since it occurs |
| // in the prefix. |
| C = NoConvention; |
| } |
| ++s; |
| continue; |
| } |
| |
| // Skip numbers, ':', etc. |
| if (!isalpha(*s)) { |
| ++s; |
| continue; |
| } |
| |
| const char *wordEnd = parseWord(s); |
| assert(wordEnd > s); |
| unsigned len = wordEnd - s; |
| |
| switch (len) { |
| default: |
| break; |
| case 3: |
| // Methods starting with 'new' follow the create rule. |
| if (AtBeginning && StringsEqualNoCase("new", s, len)) |
| C = CreateRule; |
| break; |
| case 4: |
| // Methods starting with 'alloc' or contain 'copy' follow the |
| // create rule |
| if (C == NoConvention && StringsEqualNoCase("copy", s, len)) |
| C = CreateRule; |
| else // Methods starting with 'init' follow the init rule. |
| if (AtBeginning && StringsEqualNoCase("init", s, len)) |
| C = InitRule; |
| break; |
| case 5: |
| if (AtBeginning && StringsEqualNoCase("alloc", s, len)) |
| C = CreateRule; |
| break; |
| } |
| |
| // If we aren't in the prefix and have a derived convention then just |
| // return it now. |
| if (!InPossiblePrefix && C != NoConvention) |
| return C; |
| |
| AtBeginning = false; |
| s = wordEnd; |
| } |
| |
| // We will get here if there wasn't more than one word |
| // after the prefix. |
| return C; |
| } |
| |
| static bool followsFundamentalRule(const char* s) { |
| return deriveNamingConvention(s) == CreateRule; |
| } |
| |
| static bool followsReturnRule(const char* s) { |
| NamingConvention C = deriveNamingConvention(s); |
| return C == CreateRule || C == InitRule; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Selector creation functions. |
| //===----------------------------------------------------------------------===// |
| |
| static inline Selector GetNullarySelector(const char* name, ASTContext& Ctx) { |
| IdentifierInfo* II = &Ctx.Idents.get(name); |
| return Ctx.Selectors.getSelector(0, &II); |
| } |
| |
| static inline Selector GetUnarySelector(const char* name, ASTContext& Ctx) { |
| IdentifierInfo* II = &Ctx.Idents.get(name); |
| return Ctx.Selectors.getSelector(1, &II); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Type querying functions. |
| //===----------------------------------------------------------------------===// |
| |
| static bool hasPrefix(const char* s, const char* prefix) { |
| if (!prefix) |
| return true; |
| |
| char c = *s; |
| char cP = *prefix; |
| |
| while (c != '\0' && cP != '\0') { |
| if (c != cP) break; |
| c = *(++s); |
| cP = *(++prefix); |
| } |
| |
| return cP == '\0'; |
| } |
| |
| static bool hasSuffix(const char* s, const char* suffix) { |
| const char* loc = strstr(s, suffix); |
| return loc && strcmp(suffix, loc) == 0; |
| } |
| |
| static bool isRefType(QualType RetTy, const char* prefix, |
| ASTContext* Ctx = 0, const char* name = 0) { |
| |
| if (TypedefType* TD = dyn_cast<TypedefType>(RetTy.getTypePtr())) { |
| const char* TDName = TD->getDecl()->getIdentifier()->getName(); |
| return hasPrefix(TDName, prefix) && hasSuffix(TDName, "Ref"); |
| } |
| |
| if (!Ctx || !name) |
| return false; |
| |
| // Is the type void*? |
| const PointerType* PT = RetTy->getAsPointerType(); |
| if (!(PT->getPointeeType().getUnqualifiedType() == Ctx->VoidTy)) |
| return false; |
| |
| // Does the name start with the prefix? |
| return hasPrefix(name, prefix); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Primitives used for constructing summaries for function/method calls. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| /// ArgEffect is used to summarize a function/method call's effect on a |
| /// particular argument. |
| enum ArgEffect { Autorelease, Dealloc, DecRef, DecRefMsg, DoNothing, |
| DoNothingByRef, IncRefMsg, IncRef, MakeCollectable, MayEscape, |
| NewAutoreleasePool, SelfOwn, StopTracking }; |
| |
| /// ArgEffects summarizes the effects of a function/method call on all of |
| /// its arguments. |
| typedef std::vector<std::pair<unsigned,ArgEffect> > ArgEffects; |
| } |
| |
| namespace llvm { |
| template <> struct FoldingSetTrait<ArgEffects> { |
| static void Profile(const ArgEffects& X, FoldingSetNodeID& ID) { |
| for (ArgEffects::const_iterator I = X.begin(), E = X.end(); I!= E; ++I) { |
| ID.AddInteger(I->first); |
| ID.AddInteger((unsigned) I->second); |
| } |
| } |
| }; |
| } // end llvm namespace |
| |
| namespace { |
| |
| /// RetEffect is used to summarize a function/method call's behavior with |
| /// respect to its return value. |
| class VISIBILITY_HIDDEN RetEffect { |
| public: |
| enum Kind { NoRet, Alias, OwnedSymbol, OwnedAllocatedSymbol, |
| NotOwnedSymbol, ReceiverAlias }; |
| |
| enum ObjKind { CF, ObjC, AnyObj }; |
| |
| private: |
| Kind K; |
| ObjKind O; |
| unsigned index; |
| |
| RetEffect(Kind k, unsigned idx = 0) : K(k), O(AnyObj), index(idx) {} |
| RetEffect(Kind k, ObjKind o) : K(k), O(o), index(0) {} |
| |
| public: |
| Kind getKind() const { return K; } |
| |
| ObjKind getObjKind() const { return O; } |
| |
| unsigned getIndex() const { |
| assert(getKind() == Alias); |
| return index; |
| } |
| |
| static RetEffect MakeAlias(unsigned Idx) { |
| return RetEffect(Alias, Idx); |
| } |
| static RetEffect MakeReceiverAlias() { |
| return RetEffect(ReceiverAlias); |
| } |
| static RetEffect MakeOwned(ObjKind o, bool isAllocated = false) { |
| return RetEffect(isAllocated ? OwnedAllocatedSymbol : OwnedSymbol, o); |
| } |
| static RetEffect MakeNotOwned(ObjKind o) { |
| return RetEffect(NotOwnedSymbol, o); |
| } |
| static RetEffect MakeNoRet() { |
| return RetEffect(NoRet); |
| } |
| |
| void Profile(llvm::FoldingSetNodeID& ID) const { |
| ID.AddInteger((unsigned)K); |
| ID.AddInteger((unsigned)O); |
| ID.AddInteger(index); |
| } |
| }; |
| |
| |
| class VISIBILITY_HIDDEN RetainSummary : public llvm::FoldingSetNode { |
| /// Args - an ordered vector of (index, ArgEffect) pairs, where index |
| /// specifies the argument (starting from 0). This can be sparsely |
| /// populated; arguments with no entry in Args use 'DefaultArgEffect'. |
| ArgEffects* Args; |
| |
| /// DefaultArgEffect - The default ArgEffect to apply to arguments that |
| /// do not have an entry in Args. |
| ArgEffect DefaultArgEffect; |
| |
| /// Receiver - If this summary applies to an Objective-C message expression, |
| /// this is the effect applied to the state of the receiver. |
| ArgEffect Receiver; |
| |
| /// Ret - The effect on the return value. Used to indicate if the |
| /// function/method call returns a new tracked symbol, returns an |
| /// alias of one of the arguments in the call, and so on. |
| RetEffect Ret; |
| |
| /// EndPath - Indicates that execution of this method/function should |
| /// terminate the simulation of a path. |
| bool EndPath; |
| |
| public: |
| |
| RetainSummary(ArgEffects* A, RetEffect R, ArgEffect defaultEff, |
| ArgEffect ReceiverEff, bool endpath = false) |
| : Args(A), DefaultArgEffect(defaultEff), Receiver(ReceiverEff), Ret(R), |
| EndPath(endpath) {} |
| |
| /// getArg - Return the argument effect on the argument specified by |
| /// idx (starting from 0). |
| ArgEffect getArg(unsigned idx) const { |
| |
| if (!Args) |
| return DefaultArgEffect; |
| |
| // If Args is present, it is likely to contain only 1 element. |
| // Just do a linear search. Do it from the back because functions with |
| // large numbers of arguments will be tail heavy with respect to which |
| // argument they actually modify with respect to the reference count. |
| for (ArgEffects::reverse_iterator I=Args->rbegin(), E=Args->rend(); |
| I!=E; ++I) { |
| |
| if (idx > I->first) |
| return DefaultArgEffect; |
| |
| if (idx == I->first) |
| return I->second; |
| } |
| |
| return DefaultArgEffect; |
| } |
| |
| /// getRetEffect - Returns the effect on the return value of the call. |
| RetEffect getRetEffect() const { |
| return Ret; |
| } |
| |
| /// isEndPath - Returns true if executing the given method/function should |
| /// terminate the path. |
| bool isEndPath() const { return EndPath; } |
| |
| /// getReceiverEffect - Returns the effect on the receiver of the call. |
| /// This is only meaningful if the summary applies to an ObjCMessageExpr*. |
| ArgEffect getReceiverEffect() const { |
| return Receiver; |
| } |
| |
| typedef ArgEffects::const_iterator ExprIterator; |
| |
| ExprIterator begin_args() const { return Args->begin(); } |
| ExprIterator end_args() const { return Args->end(); } |
| |
| static void Profile(llvm::FoldingSetNodeID& ID, ArgEffects* A, |
| RetEffect RetEff, ArgEffect DefaultEff, |
| ArgEffect ReceiverEff, bool EndPath) { |
| ID.AddPointer(A); |
| ID.Add(RetEff); |
| ID.AddInteger((unsigned) DefaultEff); |
| ID.AddInteger((unsigned) ReceiverEff); |
| ID.AddInteger((unsigned) EndPath); |
| } |
| |
| void Profile(llvm::FoldingSetNodeID& ID) const { |
| Profile(ID, Args, Ret, DefaultArgEffect, Receiver, EndPath); |
| } |
| }; |
| } // end anonymous namespace |
| |
| //===----------------------------------------------------------------------===// |
| // Data structures for constructing summaries. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| class VISIBILITY_HIDDEN ObjCSummaryKey { |
| IdentifierInfo* II; |
| Selector S; |
| public: |
| ObjCSummaryKey(IdentifierInfo* ii, Selector s) |
| : II(ii), S(s) {} |
| |
| ObjCSummaryKey(ObjCInterfaceDecl* d, Selector s) |
| : II(d ? d->getIdentifier() : 0), S(s) {} |
| |
| ObjCSummaryKey(Selector s) |
| : II(0), S(s) {} |
| |
| IdentifierInfo* getIdentifier() const { return II; } |
| Selector getSelector() const { return S; } |
| }; |
| } |
| |
| namespace llvm { |
| template <> struct DenseMapInfo<ObjCSummaryKey> { |
| static inline ObjCSummaryKey getEmptyKey() { |
| return ObjCSummaryKey(DenseMapInfo<IdentifierInfo*>::getEmptyKey(), |
| DenseMapInfo<Selector>::getEmptyKey()); |
| } |
| |
| static inline ObjCSummaryKey getTombstoneKey() { |
| return ObjCSummaryKey(DenseMapInfo<IdentifierInfo*>::getTombstoneKey(), |
| DenseMapInfo<Selector>::getTombstoneKey()); |
| } |
| |
| static unsigned getHashValue(const ObjCSummaryKey &V) { |
| return (DenseMapInfo<IdentifierInfo*>::getHashValue(V.getIdentifier()) |
| & 0x88888888) |
| | (DenseMapInfo<Selector>::getHashValue(V.getSelector()) |
| & 0x55555555); |
| } |
| |
| static bool isEqual(const ObjCSummaryKey& LHS, const ObjCSummaryKey& RHS) { |
| return DenseMapInfo<IdentifierInfo*>::isEqual(LHS.getIdentifier(), |
| RHS.getIdentifier()) && |
| DenseMapInfo<Selector>::isEqual(LHS.getSelector(), |
| RHS.getSelector()); |
| } |
| |
| static bool isPod() { |
| return DenseMapInfo<ObjCInterfaceDecl*>::isPod() && |
| DenseMapInfo<Selector>::isPod(); |
| } |
| }; |
| } // end llvm namespace |
| |
| namespace { |
| class VISIBILITY_HIDDEN ObjCSummaryCache { |
| typedef llvm::DenseMap<ObjCSummaryKey, RetainSummary*> MapTy; |
| MapTy M; |
| public: |
| ObjCSummaryCache() {} |
| |
| typedef MapTy::iterator iterator; |
| |
| iterator find(ObjCInterfaceDecl* D, Selector S) { |
| |
| // Do a lookup with the (D,S) pair. If we find a match return |
| // the iterator. |
| ObjCSummaryKey K(D, S); |
| MapTy::iterator I = M.find(K); |
| |
| if (I != M.end() || !D) |
| return I; |
| |
| // Walk the super chain. If we find a hit with a parent, we'll end |
| // up returning that summary. We actually allow that key (null,S), as |
| // we cache summaries for the null ObjCInterfaceDecl* to allow us to |
| // generate initial summaries without having to worry about NSObject |
| // being declared. |
| // FIXME: We may change this at some point. |
| for (ObjCInterfaceDecl* C=D->getSuperClass() ;; C=C->getSuperClass()) { |
| if ((I = M.find(ObjCSummaryKey(C, S))) != M.end()) |
| break; |
| |
| if (!C) |
| return I; |
| } |
| |
| // Cache the summary with original key to make the next lookup faster |
| // and return the iterator. |
| M[K] = I->second; |
| return I; |
| } |
| |
| |
| iterator find(Expr* Receiver, Selector S) { |
| return find(getReceiverDecl(Receiver), S); |
| } |
| |
| iterator find(IdentifierInfo* II, Selector S) { |
| // FIXME: Class method lookup. Right now we dont' have a good way |
| // of going between IdentifierInfo* and the class hierarchy. |
| iterator I = M.find(ObjCSummaryKey(II, S)); |
| return I == M.end() ? M.find(ObjCSummaryKey(S)) : I; |
| } |
| |
| ObjCInterfaceDecl* getReceiverDecl(Expr* E) { |
| |
| const PointerType* PT = E->getType()->getAsPointerType(); |
| if (!PT) return 0; |
| |
| ObjCInterfaceType* OI = dyn_cast<ObjCInterfaceType>(PT->getPointeeType()); |
| if (!OI) return 0; |
| |
| return OI ? OI->getDecl() : 0; |
| } |
| |
| iterator end() { return M.end(); } |
| |
| RetainSummary*& operator[](ObjCMessageExpr* ME) { |
| |
| Selector S = ME->getSelector(); |
| |
| if (Expr* Receiver = ME->getReceiver()) { |
| ObjCInterfaceDecl* OD = getReceiverDecl(Receiver); |
| return OD ? M[ObjCSummaryKey(OD->getIdentifier(), S)] : M[S]; |
| } |
| |
| return M[ObjCSummaryKey(ME->getClassName(), S)]; |
| } |
| |
| RetainSummary*& operator[](ObjCSummaryKey K) { |
| return M[K]; |
| } |
| |
| RetainSummary*& operator[](Selector S) { |
| return M[ ObjCSummaryKey(S) ]; |
| } |
| }; |
| } // end anonymous namespace |
| |
| //===----------------------------------------------------------------------===// |
| // Data structures for managing collections of summaries. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| class VISIBILITY_HIDDEN RetainSummaryManager { |
| |
| //==-----------------------------------------------------------------==// |
| // Typedefs. |
| //==-----------------------------------------------------------------==// |
| |
| typedef llvm::FoldingSet<llvm::FoldingSetNodeWrapper<ArgEffects> > |
| ArgEffectsSetTy; |
| |
| typedef llvm::FoldingSet<RetainSummary> |
| SummarySetTy; |
| |
| typedef llvm::DenseMap<FunctionDecl*, RetainSummary*> |
| FuncSummariesTy; |
| |
| typedef ObjCSummaryCache ObjCMethodSummariesTy; |
| |
| //==-----------------------------------------------------------------==// |
| // Data. |
| //==-----------------------------------------------------------------==// |
| |
| /// Ctx - The ASTContext object for the analyzed ASTs. |
| ASTContext& Ctx; |
| |
| /// CFDictionaryCreateII - An IdentifierInfo* representing the indentifier |
| /// "CFDictionaryCreate". |
| IdentifierInfo* CFDictionaryCreateII; |
| |
| /// GCEnabled - Records whether or not the analyzed code runs in GC mode. |
| const bool GCEnabled; |
| |
| /// SummarySet - A FoldingSet of uniqued summaries. |
| SummarySetTy SummarySet; |
| |
| /// FuncSummaries - A map from FunctionDecls to summaries. |
| FuncSummariesTy FuncSummaries; |
| |
| /// ObjCClassMethodSummaries - A map from selectors (for instance methods) |
| /// to summaries. |
| ObjCMethodSummariesTy ObjCClassMethodSummaries; |
| |
| /// ObjCMethodSummaries - A map from selectors to summaries. |
| ObjCMethodSummariesTy ObjCMethodSummaries; |
| |
| /// ArgEffectsSet - A FoldingSet of uniqued ArgEffects. |
| ArgEffectsSetTy ArgEffectsSet; |
| |
| /// BPAlloc - A BumpPtrAllocator used for allocating summaries, ArgEffects, |
| /// and all other data used by the checker. |
| llvm::BumpPtrAllocator BPAlloc; |
| |
| /// ScratchArgs - A holding buffer for construct ArgEffects. |
| ArgEffects ScratchArgs; |
| |
| RetainSummary* StopSummary; |
| |
| //==-----------------------------------------------------------------==// |
| // Methods. |
| //==-----------------------------------------------------------------==// |
| |
| /// getArgEffects - Returns a persistent ArgEffects object based on the |
| /// data in ScratchArgs. |
| ArgEffects* getArgEffects(); |
| |
| enum UnaryFuncKind { cfretain, cfrelease, cfmakecollectable }; |
| |
| public: |
| RetainSummary* getUnarySummary(const FunctionType* FT, UnaryFuncKind func); |
| |
| RetainSummary* getCFSummaryCreateRule(FunctionDecl* FD); |
| RetainSummary* getCFSummaryGetRule(FunctionDecl* FD); |
| RetainSummary* getCFCreateGetRuleSummary(FunctionDecl* FD, const char* FName); |
| |
| RetainSummary* getPersistentSummary(ArgEffects* AE, RetEffect RetEff, |
| ArgEffect ReceiverEff = DoNothing, |
| ArgEffect DefaultEff = MayEscape, |
| bool isEndPath = false); |
| |
| RetainSummary* getPersistentSummary(RetEffect RE, |
| ArgEffect ReceiverEff = DoNothing, |
| ArgEffect DefaultEff = MayEscape) { |
| return getPersistentSummary(getArgEffects(), RE, ReceiverEff, DefaultEff); |
| } |
| |
| RetainSummary* getPersistentStopSummary() { |
| if (StopSummary) |
| return StopSummary; |
| |
| StopSummary = getPersistentSummary(RetEffect::MakeNoRet(), |
| StopTracking, StopTracking); |
| |
| return StopSummary; |
| } |
| |
| RetainSummary* getInitMethodSummary(ObjCMessageExpr* ME); |
| |
| void InitializeClassMethodSummaries(); |
| void InitializeMethodSummaries(); |
| |
| bool isTrackedObjectType(QualType T); |
| |
| private: |
| |
| void addClsMethSummary(IdentifierInfo* ClsII, Selector S, |
| RetainSummary* Summ) { |
| ObjCClassMethodSummaries[ObjCSummaryKey(ClsII, S)] = Summ; |
| } |
| |
| void addNSObjectClsMethSummary(Selector S, RetainSummary *Summ) { |
| ObjCClassMethodSummaries[S] = Summ; |
| } |
| |
| void addNSObjectMethSummary(Selector S, RetainSummary *Summ) { |
| ObjCMethodSummaries[S] = Summ; |
| } |
| |
| void addClassMethSummary(const char* Cls, const char* nullaryName, |
| RetainSummary *Summ) { |
| IdentifierInfo* ClsII = &Ctx.Idents.get(Cls); |
| Selector S = GetNullarySelector(nullaryName, Ctx); |
| ObjCClassMethodSummaries[ObjCSummaryKey(ClsII, S)] = Summ; |
| } |
| |
| void addInstMethSummary(const char* Cls, const char* nullaryName, |
| RetainSummary *Summ) { |
| IdentifierInfo* ClsII = &Ctx.Idents.get(Cls); |
| Selector S = GetNullarySelector(nullaryName, Ctx); |
| ObjCMethodSummaries[ObjCSummaryKey(ClsII, S)] = Summ; |
| } |
| |
| void addInstMethSummary(const char* Cls, RetainSummary* Summ, va_list argp) { |
| |
| IdentifierInfo* ClsII = &Ctx.Idents.get(Cls); |
| llvm::SmallVector<IdentifierInfo*, 10> II; |
| |
| while (const char* s = va_arg(argp, const char*)) |
| II.push_back(&Ctx.Idents.get(s)); |
| |
| Selector S = Ctx.Selectors.getSelector(II.size(), &II[0]); |
| ObjCMethodSummaries[ObjCSummaryKey(ClsII, S)] = Summ; |
| } |
| |
| void addInstMethSummary(const char* Cls, RetainSummary* Summ, ...) { |
| va_list argp; |
| va_start(argp, Summ); |
| addInstMethSummary(Cls, Summ, argp); |
| va_end(argp); |
| } |
| |
| void addPanicSummary(const char* Cls, ...) { |
| RetainSummary* Summ = getPersistentSummary(0, RetEffect::MakeNoRet(), |
| DoNothing, DoNothing, true); |
| va_list argp; |
| va_start (argp, Cls); |
| addInstMethSummary(Cls, Summ, argp); |
| va_end(argp); |
| } |
| |
| public: |
| |
| RetainSummaryManager(ASTContext& ctx, bool gcenabled) |
| : Ctx(ctx), |
| CFDictionaryCreateII(&ctx.Idents.get("CFDictionaryCreate")), |
| GCEnabled(gcenabled), StopSummary(0) { |
| |
| InitializeClassMethodSummaries(); |
| InitializeMethodSummaries(); |
| } |
| |
| ~RetainSummaryManager(); |
| |
| RetainSummary* getSummary(FunctionDecl* FD); |
| RetainSummary* getMethodSummary(ObjCMessageExpr* ME, ObjCInterfaceDecl* ID); |
| RetainSummary* getClassMethodSummary(IdentifierInfo* ClsName, Selector S); |
| |
| bool isGCEnabled() const { return GCEnabled; } |
| }; |
| |
| } // end anonymous namespace |
| |
| //===----------------------------------------------------------------------===// |
| // Implementation of checker data structures. |
| //===----------------------------------------------------------------------===// |
| |
| RetainSummaryManager::~RetainSummaryManager() { |
| |
| // FIXME: The ArgEffects could eventually be allocated from BPAlloc, |
| // mitigating the need to do explicit cleanup of the |
| // Argument-Effect summaries. |
| |
| for (ArgEffectsSetTy::iterator I = ArgEffectsSet.begin(), |
| E = ArgEffectsSet.end(); I!=E; ++I) |
| I->getValue().~ArgEffects(); |
| } |
| |
| ArgEffects* RetainSummaryManager::getArgEffects() { |
| |
| if (ScratchArgs.empty()) |
| return NULL; |
| |
| // Compute a profile for a non-empty ScratchArgs. |
| llvm::FoldingSetNodeID profile; |
| profile.Add(ScratchArgs); |
| void* InsertPos; |
| |
| // Look up the uniqued copy, or create a new one. |
| llvm::FoldingSetNodeWrapper<ArgEffects>* E = |
| ArgEffectsSet.FindNodeOrInsertPos(profile, InsertPos); |
| |
| if (E) { |
| ScratchArgs.clear(); |
| return &E->getValue(); |
| } |
| |
| E = (llvm::FoldingSetNodeWrapper<ArgEffects>*) |
| BPAlloc.Allocate<llvm::FoldingSetNodeWrapper<ArgEffects> >(); |
| |
| new (E) llvm::FoldingSetNodeWrapper<ArgEffects>(ScratchArgs); |
| ArgEffectsSet.InsertNode(E, InsertPos); |
| |
| ScratchArgs.clear(); |
| return &E->getValue(); |
| } |
| |
| RetainSummary* |
| RetainSummaryManager::getPersistentSummary(ArgEffects* AE, RetEffect RetEff, |
| ArgEffect ReceiverEff, |
| ArgEffect DefaultEff, |
| bool isEndPath) { |
| |
| // Generate a profile for the summary. |
| llvm::FoldingSetNodeID profile; |
| RetainSummary::Profile(profile, AE, RetEff, DefaultEff, ReceiverEff, |
| isEndPath); |
| |
| // Look up the uniqued summary, or create one if it doesn't exist. |
| void* InsertPos; |
| RetainSummary* Summ = SummarySet.FindNodeOrInsertPos(profile, InsertPos); |
| |
| if (Summ) |
| return Summ; |
| |
| // Create the summary and return it. |
| Summ = (RetainSummary*) BPAlloc.Allocate<RetainSummary>(); |
| new (Summ) RetainSummary(AE, RetEff, DefaultEff, ReceiverEff, isEndPath); |
| SummarySet.InsertNode(Summ, InsertPos); |
| |
| return Summ; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Predicates. |
| //===----------------------------------------------------------------------===// |
| |
| bool RetainSummaryManager::isTrackedObjectType(QualType T) { |
| if (!Ctx.isObjCObjectPointerType(T)) |
| return false; |
| |
| // Does it subclass NSObject? |
| ObjCInterfaceType* OT = dyn_cast<ObjCInterfaceType>(T.getTypePtr()); |
| |
| // We assume that id<..>, id, and "Class" all represent tracked objects. |
| if (!OT) |
| return true; |
| |
| // Does the object type subclass NSObject? |
| // FIXME: We can memoize here if this gets too expensive. |
| IdentifierInfo* NSObjectII = &Ctx.Idents.get("NSObject"); |
| ObjCInterfaceDecl* ID = OT->getDecl(); |
| |
| for ( ; ID ; ID = ID->getSuperClass()) |
| if (ID->getIdentifier() == NSObjectII) |
| return true; |
| |
| return false; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Summary creation for functions (largely uses of Core Foundation). |
| //===----------------------------------------------------------------------===// |
| |
| static bool isRetain(FunctionDecl* FD, const char* FName) { |
| const char* loc = strstr(FName, "Retain"); |
| return loc && loc[sizeof("Retain")-1] == '\0'; |
| } |
| |
| static bool isRelease(FunctionDecl* FD, const char* FName) { |
| const char* loc = strstr(FName, "Release"); |
| return loc && loc[sizeof("Release")-1] == '\0'; |
| } |
| |
| RetainSummary* RetainSummaryManager::getSummary(FunctionDecl* FD) { |
| |
| SourceLocation Loc = FD->getLocation(); |
| |
| if (!Loc.isFileID()) |
| return NULL; |
| |
| // Look up a summary in our cache of FunctionDecls -> Summaries. |
| FuncSummariesTy::iterator I = FuncSummaries.find(FD); |
| |
| if (I != FuncSummaries.end()) |
| return I->second; |
| |
| // No summary. Generate one. |
| RetainSummary *S = 0; |
| |
| do { |
| // We generate "stop" summaries for implicitly defined functions. |
| if (FD->isImplicit()) { |
| S = getPersistentStopSummary(); |
| break; |
| } |
| |
| // [PR 3337] Use 'getAsFunctionType' to strip away any typedefs on the |
| // function's type. |
| const FunctionType* FT = FD->getType()->getAsFunctionType(); |
| const char* FName = FD->getIdentifier()->getName(); |
| |
| // Strip away preceding '_'. Doing this here will effect all the checks |
| // down below. |
| while (*FName == '_') ++FName; |
| |
| // Inspect the result type. |
| QualType RetTy = FT->getResultType(); |
| |
| // FIXME: This should all be refactored into a chain of "summary lookup" |
| // filters. |
| if (strcmp(FName, "IOServiceGetMatchingServices") == 0) { |
| // FIXES: <rdar://problem/6326900> |
| // This should be addressed using a API table. This strcmp is also |
| // a little gross, but there is no need to super optimize here. |
| assert (ScratchArgs.empty()); |
| ScratchArgs.push_back(std::make_pair(1, DecRef)); |
| S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); |
| break; |
| } |
| |
| // Enable this code once the semantics of NSDeallocateObject are resolved |
| // for GC. <rdar://problem/6619988> |
| #if 0 |
| // Handle: NSDeallocateObject(id anObject); |
| // This method does allow 'nil' (although we don't check it now). |
| if (strcmp(FName, "NSDeallocateObject") == 0) { |
| return RetTy == Ctx.VoidTy |
| ? getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, Dealloc) |
| : getPersistentStopSummary(); |
| } |
| #endif |
| |
| // Handle: id NSMakeCollectable(CFTypeRef) |
| if (strcmp(FName, "NSMakeCollectable") == 0) { |
| S = (RetTy == Ctx.getObjCIdType()) |
| ? getUnarySummary(FT, cfmakecollectable) |
| : getPersistentStopSummary(); |
| |
| break; |
| } |
| |
| if (RetTy->isPointerType()) { |
| // For CoreFoundation ('CF') types. |
| if (isRefType(RetTy, "CF", &Ctx, FName)) { |
| if (isRetain(FD, FName)) |
| S = getUnarySummary(FT, cfretain); |
| else if (strstr(FName, "MakeCollectable")) |
| S = getUnarySummary(FT, cfmakecollectable); |
| else |
| S = getCFCreateGetRuleSummary(FD, FName); |
| |
| break; |
| } |
| |
| // For CoreGraphics ('CG') types. |
| if (isRefType(RetTy, "CG", &Ctx, FName)) { |
| if (isRetain(FD, FName)) |
| S = getUnarySummary(FT, cfretain); |
| else |
| S = getCFCreateGetRuleSummary(FD, FName); |
| |
| break; |
| } |
| |
| // For the Disk Arbitration API (DiskArbitration/DADisk.h) |
| if (isRefType(RetTy, "DADisk") || |
| isRefType(RetTy, "DADissenter") || |
| isRefType(RetTy, "DASessionRef")) { |
| S = getCFCreateGetRuleSummary(FD, FName); |
| break; |
| } |
| |
| break; |
| } |
| |
| // Check for release functions, the only kind of functions that we care |
| // about that don't return a pointer type. |
| if (FName[0] == 'C' && (FName[1] == 'F' || FName[1] == 'G')) { |
| // Test for 'CGCF'. |
| if (FName[1] == 'G' && FName[2] == 'C' && FName[3] == 'F') |
| FName += 4; |
| else |
| FName += 2; |
| |
| if (isRelease(FD, FName)) |
| S = getUnarySummary(FT, cfrelease); |
| else { |
| assert (ScratchArgs.empty()); |
| // Remaining CoreFoundation and CoreGraphics functions. |
| // We use to assume that they all strictly followed the ownership idiom |
| // and that ownership cannot be transferred. While this is technically |
| // correct, many methods allow a tracked object to escape. For example: |
| // |
| // CFMutableDictionaryRef x = CFDictionaryCreateMutable(...); |
| // CFDictionaryAddValue(y, key, x); |
| // CFRelease(x); |
| // ... it is okay to use 'x' since 'y' has a reference to it |
| // |
| // We handle this and similar cases with the follow heuristic. If the |
| // function name contains "InsertValue", "SetValue" or "AddValue" then |
| // we assume that arguments may "escape." |
| // |
| ArgEffect E = (CStrInCStrNoCase(FName, "InsertValue") || |
| CStrInCStrNoCase(FName, "AddValue") || |
| CStrInCStrNoCase(FName, "SetValue") || |
| CStrInCStrNoCase(FName, "AppendValue")) |
| ? MayEscape : DoNothing; |
| |
| S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, E); |
| } |
| } |
| } |
| while (0); |
| |
| FuncSummaries[FD] = S; |
| return S; |
| } |
| |
| RetainSummary* |
| RetainSummaryManager::getCFCreateGetRuleSummary(FunctionDecl* FD, |
| const char* FName) { |
| |
| if (strstr(FName, "Create") || strstr(FName, "Copy")) |
| return getCFSummaryCreateRule(FD); |
| |
| if (strstr(FName, "Get")) |
| return getCFSummaryGetRule(FD); |
| |
| return 0; |
| } |
| |
| RetainSummary* |
| RetainSummaryManager::getUnarySummary(const FunctionType* FT, |
| UnaryFuncKind func) { |
| |
| // Sanity check that this is *really* a unary function. This can |
| // happen if people do weird things. |
| const FunctionProtoType* FTP = dyn_cast<FunctionProtoType>(FT); |
| if (!FTP || FTP->getNumArgs() != 1) |
| return getPersistentStopSummary(); |
| |
| assert (ScratchArgs.empty()); |
| |
| switch (func) { |
| case cfretain: { |
| ScratchArgs.push_back(std::make_pair(0, IncRef)); |
| return getPersistentSummary(RetEffect::MakeAlias(0), |
| DoNothing, DoNothing); |
| } |
| |
| case cfrelease: { |
| ScratchArgs.push_back(std::make_pair(0, DecRef)); |
| return getPersistentSummary(RetEffect::MakeNoRet(), |
| DoNothing, DoNothing); |
| } |
| |
| case cfmakecollectable: { |
| ScratchArgs.push_back(std::make_pair(0, MakeCollectable)); |
| return getPersistentSummary(RetEffect::MakeAlias(0),DoNothing, DoNothing); |
| } |
| |
| default: |
| assert (false && "Not a supported unary function."); |
| return 0; |
| } |
| } |
| |
| RetainSummary* RetainSummaryManager::getCFSummaryCreateRule(FunctionDecl* FD) { |
| assert (ScratchArgs.empty()); |
| |
| if (FD->getIdentifier() == CFDictionaryCreateII) { |
| ScratchArgs.push_back(std::make_pair(1, DoNothingByRef)); |
| ScratchArgs.push_back(std::make_pair(2, DoNothingByRef)); |
| } |
| |
| return getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true)); |
| } |
| |
| RetainSummary* RetainSummaryManager::getCFSummaryGetRule(FunctionDecl* FD) { |
| assert (ScratchArgs.empty()); |
| return getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::CF), |
| DoNothing, DoNothing); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Summary creation for Selectors. |
| //===----------------------------------------------------------------------===// |
| |
| RetainSummary* |
| RetainSummaryManager::getInitMethodSummary(ObjCMessageExpr* ME) { |
| assert(ScratchArgs.empty()); |
| |
| // 'init' methods only return an alias if the return type is a location type. |
| QualType T = ME->getType(); |
| RetainSummary* Summ = |
| getPersistentSummary(Loc::IsLocType(T) ? RetEffect::MakeReceiverAlias() |
| : RetEffect::MakeNoRet()); |
| |
| ObjCMethodSummaries[ME] = Summ; |
| return Summ; |
| } |
| |
| |
| RetainSummary* |
| RetainSummaryManager::getMethodSummary(ObjCMessageExpr* ME, |
| ObjCInterfaceDecl* ID) { |
| |
| Selector S = ME->getSelector(); |
| |
| // Look up a summary in our summary cache. |
| ObjCMethodSummariesTy::iterator I = ObjCMethodSummaries.find(ID, S); |
| |
| if (I != ObjCMethodSummaries.end()) |
| return I->second; |
| |
| // "initXXX": pass-through for receiver. |
| const char* s = S.getIdentifierInfoForSlot(0)->getName(); |
| assert (ScratchArgs.empty()); |
| |
| if (deriveNamingConvention(s) == InitRule) |
| return getInitMethodSummary(ME); |
| |
| // Look for methods that return an owned object. |
| if (!isTrackedObjectType(Ctx.getCanonicalType(ME->getType()))) |
| return 0; |
| |
| if (followsFundamentalRule(s)) { |
| RetEffect E = isGCEnabled() ? RetEffect::MakeNoRet() |
| : RetEffect::MakeOwned(RetEffect::ObjC, true); |
| RetainSummary* Summ = getPersistentSummary(E); |
| ObjCMethodSummaries[ME] = Summ; |
| return Summ; |
| } |
| |
| return 0; |
| } |
| |
| RetainSummary* |
| RetainSummaryManager::getClassMethodSummary(IdentifierInfo* ClsName, |
| Selector S) { |
| |
| // FIXME: Eventually we should properly do class method summaries, but |
| // it requires us being able to walk the type hierarchy. Unfortunately, |
| // we cannot do this with just an IdentifierInfo* for the class name. |
| |
| // Look up a summary in our cache of Selectors -> Summaries. |
| ObjCMethodSummariesTy::iterator I = ObjCClassMethodSummaries.find(ClsName, S); |
| |
| if (I != ObjCClassMethodSummaries.end()) |
| return I->second; |
| |
| return 0; |
| } |
| |
| void RetainSummaryManager::InitializeClassMethodSummaries() { |
| |
| assert (ScratchArgs.empty()); |
| |
| RetEffect E = isGCEnabled() ? RetEffect::MakeNoRet() |
| : RetEffect::MakeOwned(RetEffect::ObjC, true); |
| |
| RetainSummary* Summ = getPersistentSummary(E); |
| |
| // Create the summaries for "alloc", "new", and "allocWithZone:" for |
| // NSObject and its derivatives. |
| addNSObjectClsMethSummary(GetNullarySelector("alloc", Ctx), Summ); |
| addNSObjectClsMethSummary(GetNullarySelector("new", Ctx), Summ); |
| addNSObjectClsMethSummary(GetUnarySelector("allocWithZone", Ctx), Summ); |
| |
| // Create the [NSAssertionHandler currentHander] summary. |
| addClsMethSummary(&Ctx.Idents.get("NSAssertionHandler"), |
| GetNullarySelector("currentHandler", Ctx), |
| getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::ObjC))); |
| |
| // Create the [NSAutoreleasePool addObject:] summary. |
| ScratchArgs.push_back(std::make_pair(0, Autorelease)); |
| addClsMethSummary(&Ctx.Idents.get("NSAutoreleasePool"), |
| GetUnarySelector("addObject", Ctx), |
| getPersistentSummary(RetEffect::MakeNoRet(), |
| DoNothing, Autorelease)); |
| } |
| |
| void RetainSummaryManager::InitializeMethodSummaries() { |
| |
| assert (ScratchArgs.empty()); |
| |
| // Create the "init" selector. It just acts as a pass-through for the |
| // receiver. |
| RetainSummary* InitSumm = |
| getPersistentSummary(RetEffect::MakeReceiverAlias()); |
| addNSObjectMethSummary(GetNullarySelector("init", Ctx), InitSumm); |
| |
| // The next methods are allocators. |
| RetEffect E = isGCEnabled() ? RetEffect::MakeNoRet() |
| : RetEffect::MakeOwned(RetEffect::ObjC, true); |
| |
| RetainSummary* Summ = getPersistentSummary(E); |
| |
| // Create the "copy" selector. |
| addNSObjectMethSummary(GetNullarySelector("copy", Ctx), Summ); |
| |
| // Create the "mutableCopy" selector. |
| addNSObjectMethSummary(GetNullarySelector("mutableCopy", Ctx), Summ); |
| |
| // Create the "retain" selector. |
| E = RetEffect::MakeReceiverAlias(); |
| Summ = getPersistentSummary(E, IncRefMsg); |
| addNSObjectMethSummary(GetNullarySelector("retain", Ctx), Summ); |
| |
| // Create the "release" selector. |
| Summ = getPersistentSummary(E, DecRefMsg); |
| addNSObjectMethSummary(GetNullarySelector("release", Ctx), Summ); |
| |
| // Create the "drain" selector. |
| Summ = getPersistentSummary(E, isGCEnabled() ? DoNothing : DecRef); |
| addNSObjectMethSummary(GetNullarySelector("drain", Ctx), Summ); |
| |
| // Create the -dealloc summary. |
| Summ = getPersistentSummary(RetEffect::MakeNoRet(), Dealloc); |
| addNSObjectMethSummary(GetNullarySelector("dealloc", Ctx), Summ); |
| |
| // Create the "autorelease" selector. |
| Summ = getPersistentSummary(E, Autorelease); |
| addNSObjectMethSummary(GetNullarySelector("autorelease", Ctx), Summ); |
| |
| // Specially handle NSAutoreleasePool. |
| addInstMethSummary("NSAutoreleasePool", "init", |
| getPersistentSummary(RetEffect::MakeReceiverAlias(), |
| NewAutoreleasePool)); |
| |
| // For NSWindow, allocated objects are (initially) self-owned. |
| // FIXME: For now we opt for false negatives with NSWindow, as these objects |
| // self-own themselves. However, they only do this once they are displayed. |
| // Thus, we need to track an NSWindow's display status. |
| // This is tracked in <rdar://problem/6062711>. |
| // See also http://llvm.org/bugs/show_bug.cgi?id=3714. |
| RetainSummary *NoTrackYet = getPersistentSummary(RetEffect::MakeNoRet()); |
| |
| addClassMethSummary("NSWindow", "alloc", NoTrackYet); |
| |
| |
| #if 0 |
| RetainSummary *NSWindowSumm = |
| getPersistentSummary(RetEffect::MakeReceiverAlias(), StopTracking); |
| |
| addInstMethSummary("NSWindow", NSWindowSumm, "initWithContentRect", |
| "styleMask", "backing", "defer", NULL); |
| |
| addInstMethSummary("NSWindow", NSWindowSumm, "initWithContentRect", |
| "styleMask", "backing", "defer", "screen", NULL); |
| #endif |
| |
| // For NSPanel (which subclasses NSWindow), allocated objects are not |
| // self-owned. |
| // FIXME: For now we don't track NSPanels. object for the same reason |
| // as for NSWindow objects. |
| addClassMethSummary("NSPanel", "alloc", NoTrackYet); |
| |
| addInstMethSummary("NSPanel", InitSumm, "initWithContentRect", |
| "styleMask", "backing", "defer", NULL); |
| |
| addInstMethSummary("NSPanel", InitSumm, "initWithContentRect", |
| "styleMask", "backing", "defer", "screen", NULL); |
| |
| // Create NSAssertionHandler summaries. |
| addPanicSummary("NSAssertionHandler", "handleFailureInFunction", "file", |
| "lineNumber", "description", NULL); |
| |
| addPanicSummary("NSAssertionHandler", "handleFailureInMethod", "object", |
| "file", "lineNumber", "description", NULL); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Reference-counting logic (typestate + counts). |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| |
| class VISIBILITY_HIDDEN RefVal { |
| public: |
| enum Kind { |
| Owned = 0, // Owning reference. |
| NotOwned, // Reference is not owned by still valid (not freed). |
| Released, // Object has been released. |
| ReturnedOwned, // Returned object passes ownership to caller. |
| ReturnedNotOwned, // Return object does not pass ownership to caller. |
| ERROR_START, |
| ErrorDeallocNotOwned, // -dealloc called on non-owned object. |
| ErrorDeallocGC, // Calling -dealloc with GC enabled. |
| ErrorUseAfterRelease, // Object used after released. |
| ErrorReleaseNotOwned, // Release of an object that was not owned. |
| ERROR_LEAK_START, |
| ErrorLeak, // A memory leak due to excessive reference counts. |
| ErrorLeakReturned // A memory leak due to the returning method not having |
| // the correct naming conventions. |
| }; |
| |
| private: |
| Kind kind; |
| RetEffect::ObjKind okind; |
| unsigned Cnt; |
| QualType T; |
| |
| RefVal(Kind k, RetEffect::ObjKind o, unsigned cnt, QualType t) |
| : kind(k), okind(o), Cnt(cnt), T(t) {} |
| |
| RefVal(Kind k, unsigned cnt = 0) |
| : kind(k), okind(RetEffect::AnyObj), Cnt(cnt) {} |
| |
| public: |
| Kind getKind() const { return kind; } |
| |
| RetEffect::ObjKind getObjKind() const { return okind; } |
| |
| unsigned getCount() const { return Cnt; } |
| void clearCounts() { Cnt = 0; } |
| |
| QualType getType() const { return T; } |
| |
| // Useful predicates. |
| |
| static bool isError(Kind k) { return k >= ERROR_START; } |
| |
| static bool isLeak(Kind k) { return k >= ERROR_LEAK_START; } |
| |
| bool isOwned() const { |
| return getKind() == Owned; |
| } |
| |
| bool isNotOwned() const { |
| return getKind() == NotOwned; |
| } |
| |
| bool isReturnedOwned() const { |
| return getKind() == ReturnedOwned; |
| } |
| |
| bool isReturnedNotOwned() const { |
| return getKind() == ReturnedNotOwned; |
| } |
| |
| bool isNonLeakError() const { |
| Kind k = getKind(); |
| return isError(k) && !isLeak(k); |
| } |
| |
| static RefVal makeOwned(RetEffect::ObjKind o, QualType t, |
| unsigned Count = 1) { |
| return RefVal(Owned, o, Count, t); |
| } |
| |
| static RefVal makeNotOwned(RetEffect::ObjKind o, QualType t, |
| unsigned Count = 0) { |
| return RefVal(NotOwned, o, Count, t); |
| } |
| |
| static RefVal makeReturnedOwned(unsigned Count) { |
| return RefVal(ReturnedOwned, Count); |
| } |
| |
| static RefVal makeReturnedNotOwned() { |
| return RefVal(ReturnedNotOwned); |
| } |
| |
| // Comparison, profiling, and pretty-printing. |
| |
| bool operator==(const RefVal& X) const { |
| return kind == X.kind && Cnt == X.Cnt && T == X.T; |
| } |
| |
| RefVal operator-(size_t i) const { |
| return RefVal(getKind(), getObjKind(), getCount() - i, getType()); |
| } |
| |
| RefVal operator+(size_t i) const { |
| return RefVal(getKind(), getObjKind(), getCount() + i, getType()); |
| } |
| |
| RefVal operator^(Kind k) const { |
| return RefVal(k, getObjKind(), getCount(), getType()); |
| } |
| |
| void Profile(llvm::FoldingSetNodeID& ID) const { |
| ID.AddInteger((unsigned) kind); |
| ID.AddInteger(Cnt); |
| ID.Add(T); |
| } |
| |
| void print(std::ostream& Out) const; |
| }; |
| |
| void RefVal::print(std::ostream& Out) const { |
| if (!T.isNull()) |
| Out << "Tracked Type:" << T.getAsString() << '\n'; |
| |
| switch (getKind()) { |
| default: assert(false); |
| case Owned: { |
| Out << "Owned"; |
| unsigned cnt = getCount(); |
| if (cnt) Out << " (+ " << cnt << ")"; |
| break; |
| } |
| |
| case NotOwned: { |
| Out << "NotOwned"; |
| unsigned cnt = getCount(); |
| if (cnt) Out << " (+ " << cnt << ")"; |
| break; |
| } |
| |
| case ReturnedOwned: { |
| Out << "ReturnedOwned"; |
| unsigned cnt = getCount(); |
| if (cnt) Out << " (+ " << cnt << ")"; |
| break; |
| } |
| |
| case ReturnedNotOwned: { |
| Out << "ReturnedNotOwned"; |
| unsigned cnt = getCount(); |
| if (cnt) Out << " (+ " << cnt << ")"; |
| break; |
| } |
| |
| case Released: |
| Out << "Released"; |
| break; |
| |
| case ErrorDeallocGC: |
| Out << "-dealloc (GC)"; |
| break; |
| |
| case ErrorDeallocNotOwned: |
| Out << "-dealloc (not-owned)"; |
| break; |
| |
| case ErrorLeak: |
| Out << "Leaked"; |
| break; |
| |
| case ErrorLeakReturned: |
| Out << "Leaked (Bad naming)"; |
| break; |
| |
| case ErrorUseAfterRelease: |
| Out << "Use-After-Release [ERROR]"; |
| break; |
| |
| case ErrorReleaseNotOwned: |
| Out << "Release of Not-Owned [ERROR]"; |
| break; |
| } |
| } |
| |
| } // end anonymous namespace |
| |
| //===----------------------------------------------------------------------===// |
| // RefBindings - State used to track object reference counts. |
| //===----------------------------------------------------------------------===// |
| |
| typedef llvm::ImmutableMap<SymbolRef, RefVal> RefBindings; |
| static int RefBIndex = 0; |
| static std::pair<const void*, const void*> LeakProgramPointTag(&RefBIndex, 0); |
| |
| namespace clang { |
| template<> |
| struct GRStateTrait<RefBindings> : public GRStatePartialTrait<RefBindings> { |
| static inline void* GDMIndex() { return &RefBIndex; } |
| }; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // AutoreleaseBindings - State used to track objects in autorelease pools. |
| //===----------------------------------------------------------------------===// |
| |
| typedef llvm::ImmutableMap<SymbolRef, unsigned> ARCounts; |
| typedef llvm::ImmutableMap<SymbolRef, ARCounts> ARPoolContents; |
| typedef llvm::ImmutableList<SymbolRef> ARStack; |
| |
| static int AutoRCIndex = 0; |
| static int AutoRBIndex = 0; |
| |
| namespace { class VISIBILITY_HIDDEN AutoreleasePoolContents {}; } |
| namespace { class VISIBILITY_HIDDEN AutoreleaseStack {}; } |
| |
| namespace clang { |
| template<> struct GRStateTrait<AutoreleaseStack> |
| : public GRStatePartialTrait<ARStack> { |
| static inline void* GDMIndex() { return &AutoRBIndex; } |
| }; |
| |
| template<> struct GRStateTrait<AutoreleasePoolContents> |
| : public GRStatePartialTrait<ARPoolContents> { |
| static inline void* GDMIndex() { return &AutoRCIndex; } |
| }; |
| } // end clang namespace |
| |
| static SymbolRef GetCurrentAutoreleasePool(const GRState* state) { |
| ARStack stack = state->get<AutoreleaseStack>(); |
| return stack.isEmpty() ? SymbolRef() : stack.getHead(); |
| } |
| |
| static GRStateRef SendAutorelease(GRStateRef state, ARCounts::Factory &F, |
| SymbolRef sym) { |
| |
| SymbolRef pool = GetCurrentAutoreleasePool(state); |
| const ARCounts *cnts = state.get<AutoreleasePoolContents>(pool); |
| ARCounts newCnts(0); |
| |
| if (cnts) { |
| const unsigned *cnt = (*cnts).lookup(sym); |
| newCnts = F.Add(*cnts, sym, cnt ? *cnt + 1 : 1); |
| } |
| else |
| newCnts = F.Add(F.GetEmptyMap(), sym, 1); |
| |
| return state.set<AutoreleasePoolContents>(pool, newCnts); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Transfer functions. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| |
| class VISIBILITY_HIDDEN CFRefCount : public GRSimpleVals { |
| public: |
| class BindingsPrinter : public GRState::Printer { |
| public: |
| virtual void Print(std::ostream& Out, const GRState* state, |
| const char* nl, const char* sep); |
| }; |
| |
| private: |
| typedef llvm::DenseMap<const GRExprEngine::NodeTy*, const RetainSummary*> |
| SummaryLogTy; |
| |
| RetainSummaryManager Summaries; |
| SummaryLogTy SummaryLog; |
| const LangOptions& LOpts; |
| ARCounts::Factory ARCountFactory; |
| |
| BugType *useAfterRelease, *releaseNotOwned; |
| BugType *deallocGC, *deallocNotOwned; |
| BugType *leakWithinFunction, *leakAtReturn; |
| BugReporter *BR; |
| |
| GRStateRef Update(GRStateRef state, SymbolRef sym, RefVal V, ArgEffect E, |
| RefVal::Kind& hasErr); |
| |
| void ProcessNonLeakError(ExplodedNodeSet<GRState>& Dst, |
| GRStmtNodeBuilder<GRState>& Builder, |
| Expr* NodeExpr, Expr* ErrorExpr, |
| ExplodedNode<GRState>* Pred, |
| const GRState* St, |
| RefVal::Kind hasErr, SymbolRef Sym); |
| |
| std::pair<GRStateRef, bool> |
| HandleSymbolDeath(GRStateManager& VMgr, const GRState* St, |
| const Decl* CD, SymbolRef sid, RefVal V, bool& hasLeak); |
| |
| public: |
| CFRefCount(ASTContext& Ctx, bool gcenabled, const LangOptions& lopts) |
| : Summaries(Ctx, gcenabled), |
| LOpts(lopts), useAfterRelease(0), releaseNotOwned(0), |
| deallocGC(0), deallocNotOwned(0), |
| leakWithinFunction(0), leakAtReturn(0), BR(0) {} |
| |
| virtual ~CFRefCount() {} |
| |
| void RegisterChecks(BugReporter &BR); |
| |
| virtual void RegisterPrinters(std::vector<GRState::Printer*>& Printers) { |
| Printers.push_back(new BindingsPrinter()); |
| } |
| |
| bool isGCEnabled() const { return Summaries.isGCEnabled(); } |
| const LangOptions& getLangOptions() const { return LOpts; } |
| |
| const RetainSummary *getSummaryOfNode(const ExplodedNode<GRState> *N) const { |
| SummaryLogTy::const_iterator I = SummaryLog.find(N); |
| return I == SummaryLog.end() ? 0 : I->second; |
| } |
| |
| // Calls. |
| |
| void EvalSummary(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Eng, |
| GRStmtNodeBuilder<GRState>& Builder, |
| Expr* Ex, |
| Expr* Receiver, |
| RetainSummary* Summ, |
| ExprIterator arg_beg, ExprIterator arg_end, |
| ExplodedNode<GRState>* Pred); |
| |
| virtual void EvalCall(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Eng, |
| GRStmtNodeBuilder<GRState>& Builder, |
| CallExpr* CE, SVal L, |
| ExplodedNode<GRState>* Pred); |
| |
| |
| virtual void EvalObjCMessageExpr(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Engine, |
| GRStmtNodeBuilder<GRState>& Builder, |
| ObjCMessageExpr* ME, |
| ExplodedNode<GRState>* Pred); |
| |
| bool EvalObjCMessageExprAux(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Engine, |
| GRStmtNodeBuilder<GRState>& Builder, |
| ObjCMessageExpr* ME, |
| ExplodedNode<GRState>* Pred); |
| |
| // Stores. |
| virtual void EvalBind(GRStmtNodeBuilderRef& B, SVal location, SVal val); |
| |
| // End-of-path. |
| |
| virtual void EvalEndPath(GRExprEngine& Engine, |
| GREndPathNodeBuilder<GRState>& Builder); |
| |
| virtual void EvalDeadSymbols(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Engine, |
| GRStmtNodeBuilder<GRState>& Builder, |
| ExplodedNode<GRState>* Pred, |
| Stmt* S, const GRState* state, |
| SymbolReaper& SymReaper); |
| |
| // Return statements. |
| |
| virtual void EvalReturn(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Engine, |
| GRStmtNodeBuilder<GRState>& Builder, |
| ReturnStmt* S, |
| ExplodedNode<GRState>* Pred); |
| |
| // Assumptions. |
| |
| virtual const GRState* EvalAssume(GRStateManager& VMgr, |
| const GRState* St, SVal Cond, |
| bool Assumption, bool& isFeasible); |
| }; |
| |
| } // end anonymous namespace |
| |
| static void PrintPool(std::ostream &Out, SymbolRef Sym, const GRState *state) { |
| Out << ' '; |
| if (Sym) |
| Out << Sym->getSymbolID(); |
| else |
| Out << "<pool>"; |
| Out << ":{"; |
| |
| // Get the contents of the pool. |
| if (const ARCounts *cnts = state->get<AutoreleasePoolContents>(Sym)) |
| for (ARCounts::iterator J=cnts->begin(), EJ=cnts->end(); J != EJ; ++J) |
| Out << '(' << J.getKey() << ',' << J.getData() << ')'; |
| |
| Out << '}'; |
| } |
| |
| void CFRefCount::BindingsPrinter::Print(std::ostream& Out, const GRState* state, |
| const char* nl, const char* sep) { |
| |
| |
| |
| RefBindings B = state->get<RefBindings>(); |
| |
| if (!B.isEmpty()) |
| Out << sep << nl; |
| |
| for (RefBindings::iterator I=B.begin(), E=B.end(); I!=E; ++I) { |
| Out << (*I).first << " : "; |
| (*I).second.print(Out); |
| Out << nl; |
| } |
| |
| // Print the autorelease stack. |
| Out << sep << nl << "AR pool stack:"; |
| ARStack stack = state->get<AutoreleaseStack>(); |
| |
| PrintPool(Out, SymbolRef(), state); // Print the caller's pool. |
| for (ARStack::iterator I=stack.begin(), E=stack.end(); I!=E; ++I) |
| PrintPool(Out, *I, state); |
| |
| Out << nl; |
| } |
| |
| static inline ArgEffect GetArgE(RetainSummary* Summ, unsigned idx) { |
| return Summ ? Summ->getArg(idx) : MayEscape; |
| } |
| |
| static inline RetEffect GetRetEffect(RetainSummary* Summ) { |
| return Summ ? Summ->getRetEffect() : RetEffect::MakeNoRet(); |
| } |
| |
| static inline ArgEffect GetReceiverE(RetainSummary* Summ) { |
| return Summ ? Summ->getReceiverEffect() : DoNothing; |
| } |
| |
| static inline bool IsEndPath(RetainSummary* Summ) { |
| return Summ ? Summ->isEndPath() : false; |
| } |
| |
| |
| /// GetReturnType - Used to get the return type of a message expression or |
| /// function call with the intention of affixing that type to a tracked symbol. |
| /// While the the return type can be queried directly from RetEx, when |
| /// invoking class methods we augment to the return type to be that of |
| /// a pointer to the class (as opposed it just being id). |
| static QualType GetReturnType(Expr* RetE, ASTContext& Ctx) { |
| |
| QualType RetTy = RetE->getType(); |
| |
| // FIXME: We aren't handling id<...>. |
| const PointerType* PT = RetTy->getAsPointerType(); |
| if (!PT) |
| return RetTy; |
| |
| // If RetEx is not a message expression just return its type. |
| // If RetEx is a message expression, return its types if it is something |
| /// more specific than id. |
| |
| ObjCMessageExpr* ME = dyn_cast<ObjCMessageExpr>(RetE); |
| |
| if (!ME || !Ctx.isObjCIdStructType(PT->getPointeeType())) |
| return RetTy; |
| |
| ObjCInterfaceDecl* D = ME->getClassInfo().first; |
| |
| // At this point we know the return type of the message expression is id. |
| // If we have an ObjCInterceDecl, we know this is a call to a class method |
| // whose type we can resolve. In such cases, promote the return type to |
| // Class*. |
| return !D ? RetTy : Ctx.getPointerType(Ctx.getObjCInterfaceType(D)); |
| } |
| |
| |
| void CFRefCount::EvalSummary(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Eng, |
| GRStmtNodeBuilder<GRState>& Builder, |
| Expr* Ex, |
| Expr* Receiver, |
| RetainSummary* Summ, |
| ExprIterator arg_beg, ExprIterator arg_end, |
| ExplodedNode<GRState>* Pred) { |
| |
| // Get the state. |
| GRStateRef state(Builder.GetState(Pred), Eng.getStateManager()); |
| ASTContext& Ctx = Eng.getStateManager().getContext(); |
| |
| // Evaluate the effect of the arguments. |
| RefVal::Kind hasErr = (RefVal::Kind) 0; |
| unsigned idx = 0; |
| Expr* ErrorExpr = NULL; |
| SymbolRef ErrorSym = 0; |
| |
| for (ExprIterator I = arg_beg; I != arg_end; ++I, ++idx) { |
| SVal V = state.GetSValAsScalarOrLoc(*I); |
| SymbolRef Sym = V.getAsLocSymbol(); |
| |
| if (Sym) |
| if (RefBindings::data_type* T = state.get<RefBindings>(Sym)) { |
| state = Update(state, Sym, *T, GetArgE(Summ, idx), hasErr); |
| if (hasErr) { |
| ErrorExpr = *I; |
| ErrorSym = Sym; |
| break; |
| } |
| continue; |
| } |
| |
| if (isa<Loc>(V)) { |
| if (loc::MemRegionVal* MR = dyn_cast<loc::MemRegionVal>(&V)) { |
| if (GetArgE(Summ, idx) == DoNothingByRef) |
| continue; |
| |
| // Invalidate the value of the variable passed by reference. |
| |
| // FIXME: Either this logic should also be replicated in GRSimpleVals |
| // or should be pulled into a separate "constraint engine." |
| |
| // FIXME: We can have collisions on the conjured symbol if the |
| // expression *I also creates conjured symbols. We probably want |
| // to identify conjured symbols by an expression pair: the enclosing |
| // expression (the context) and the expression itself. This should |
| // disambiguate conjured symbols. |
| |
| const TypedRegion* R = dyn_cast<TypedRegion>(MR->getRegion()); |
| |
| // Blast through TypedViewRegions to get the original region type. |
| while (R) { |
| const TypedViewRegion* ATR = dyn_cast<TypedViewRegion>(R); |
| if (!ATR) break; |
| R = dyn_cast<TypedRegion>(ATR->getSuperRegion()); |
| } |
| |
| if (R) { |
| // Is the invalidated variable something that we were tracking? |
| SymbolRef Sym = state.GetSValAsScalarOrLoc(R).getAsLocSymbol(); |
| |
| // Remove any existing reference-count binding. |
| if (Sym) state = state.remove<RefBindings>(Sym); |
| |
| if (R->isBoundable(Ctx)) { |
| // Set the value of the variable to be a conjured symbol. |
| unsigned Count = Builder.getCurrentBlockCount(); |
| QualType T = R->getRValueType(Ctx); |
| |
| if (Loc::IsLocType(T) || (T->isIntegerType() && T->isScalarType())){ |
| SVal V = SVal::GetConjuredSymbolVal(Eng.getSymbolManager(), |
| Eng.getStoreManager().getRegionManager(), *I, T, Count); |
| state = state.BindLoc(Loc::MakeVal(R), V); |
| } |
| else if (const RecordType *RT = T->getAsStructureType()) { |
| // Handle structs in a not so awesome way. Here we just |
| // eagerly bind new symbols to the fields. In reality we |
| // should have the store manager handle this. The idea is just |
| // to prototype some basic functionality here. All of this logic |
| // should one day soon just go away. |
| const RecordDecl *RD = RT->getDecl()->getDefinition(Ctx); |
| |
| // No record definition. There is nothing we can do. |
| if (!RD) |
| continue; |
| |
| MemRegionManager &MRMgr = state.getManager().getRegionManager(); |
| |
| // Iterate through the fields and construct new symbols. |
| for (RecordDecl::field_iterator FI=RD->field_begin(Ctx), |
| FE=RD->field_end(Ctx); FI!=FE; ++FI) { |
| |
| // For now just handle scalar fields. |
| FieldDecl *FD = *FI; |
| QualType FT = FD->getType(); |
| |
| if (Loc::IsLocType(FT) || |
| (FT->isIntegerType() && FT->isScalarType())) { |
| |
| const FieldRegion* FR = MRMgr.getFieldRegion(FD, R); |
| |
| SVal V = SVal::GetConjuredSymbolVal(Eng.getSymbolManager(), |
| Eng.getStoreManager().getRegionManager(), *I, FT, Count); |
| |
| state = state.BindLoc(Loc::MakeVal(FR), V); |
| } |
| } |
| } |
| else { |
| // Just blast away other values. |
| state = state.BindLoc(*MR, UnknownVal()); |
| } |
| } |
| } |
| else |
| state = state.BindLoc(*MR, UnknownVal()); |
| } |
| else { |
| // Nuke all other arguments passed by reference. |
| state = state.Unbind(cast<Loc>(V)); |
| } |
| } |
| else if (isa<nonloc::LocAsInteger>(V)) |
| state = state.Unbind(cast<nonloc::LocAsInteger>(V).getLoc()); |
| } |
| |
| // Evaluate the effect on the message receiver. |
| if (!ErrorExpr && Receiver) { |
| SymbolRef Sym = state.GetSValAsScalarOrLoc(Receiver).getAsLocSymbol(); |
| if (Sym) { |
| if (const RefVal* T = state.get<RefBindings>(Sym)) { |
| state = Update(state, Sym, *T, GetReceiverE(Summ), hasErr); |
| if (hasErr) { |
| ErrorExpr = Receiver; |
| ErrorSym = Sym; |
| } |
| } |
| } |
| } |
| |
| // Process any errors. |
| if (hasErr) { |
| ProcessNonLeakError(Dst, Builder, Ex, ErrorExpr, Pred, state, |
| hasErr, ErrorSym); |
| return; |
| } |
| |
| // Consult the summary for the return value. |
| RetEffect RE = GetRetEffect(Summ); |
| |
| switch (RE.getKind()) { |
| default: |
| assert (false && "Unhandled RetEffect."); break; |
| |
| case RetEffect::NoRet: { |
| |
| // Make up a symbol for the return value (not reference counted). |
| // FIXME: This is basically copy-and-paste from GRSimpleVals. We |
| // should compose behavior, not copy it. |
| |
| // FIXME: We eventually should handle structs and other compound types |
| // that are returned by value. |
| |
| QualType T = Ex->getType(); |
| |
| if (Loc::IsLocType(T) || (T->isIntegerType() && T->isScalarType())) { |
| unsigned Count = Builder.getCurrentBlockCount(); |
| SVal X = SVal::GetConjuredSymbolVal(Eng.getSymbolManager(), |
| Eng.getStoreManager().getRegionManager(), Ex, T, Count); |
| state = state.BindExpr(Ex, X, false); |
| } |
| |
| break; |
| } |
| |
| case RetEffect::Alias: { |
| unsigned idx = RE.getIndex(); |
| assert (arg_end >= arg_beg); |
| assert (idx < (unsigned) (arg_end - arg_beg)); |
| SVal V = state.GetSValAsScalarOrLoc(*(arg_beg+idx)); |
| state = state.BindExpr(Ex, V, false); |
| break; |
| } |
| |
| case RetEffect::ReceiverAlias: { |
| assert (Receiver); |
| SVal V = state.GetSValAsScalarOrLoc(Receiver); |
| state = state.BindExpr(Ex, V, false); |
| break; |
| } |
| |
| case RetEffect::OwnedAllocatedSymbol: |
| case RetEffect::OwnedSymbol: { |
| unsigned Count = Builder.getCurrentBlockCount(); |
| ValueManager &ValMgr = Eng.getValueManager(); |
| SymbolRef Sym = ValMgr.getConjuredSymbol(Ex, Count); |
| QualType RetT = GetReturnType(Ex, ValMgr.getContext()); |
| state = state.set<RefBindings>(Sym, RefVal::makeOwned(RE.getObjKind(), |
| RetT)); |
| state = state.BindExpr(Ex, ValMgr.makeRegionVal(Sym), false); |
| |
| // FIXME: Add a flag to the checker where allocations are assumed to |
| // *not fail. |
| #if 0 |
| if (RE.getKind() == RetEffect::OwnedAllocatedSymbol) { |
| bool isFeasible; |
| state = state.Assume(loc::SymbolVal(Sym), true, isFeasible); |
| assert(isFeasible && "Cannot assume fresh symbol is non-null."); |
| } |
| #endif |
| |
| break; |
| } |
| |
| case RetEffect::NotOwnedSymbol: { |
| unsigned Count = Builder.getCurrentBlockCount(); |
| ValueManager &ValMgr = Eng.getValueManager(); |
| SymbolRef Sym = ValMgr.getConjuredSymbol(Ex, Count); |
| QualType RetT = GetReturnType(Ex, ValMgr.getContext()); |
| state = state.set<RefBindings>(Sym, RefVal::makeNotOwned(RE.getObjKind(), |
| RetT)); |
| state = state.BindExpr(Ex, ValMgr.makeRegionVal(Sym), false); |
| break; |
| } |
| } |
| |
| // Generate a sink node if we are at the end of a path. |
| GRExprEngine::NodeTy *NewNode = |
| IsEndPath(Summ) ? Builder.MakeSinkNode(Dst, Ex, Pred, state) |
| : Builder.MakeNode(Dst, Ex, Pred, state); |
| |
| // Annotate the edge with summary we used. |
| // FIXME: This assumes that we always use the same summary when generating |
| // this node. |
| if (NewNode) SummaryLog[NewNode] = Summ; |
| } |
| |
| |
| void CFRefCount::EvalCall(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Eng, |
| GRStmtNodeBuilder<GRState>& Builder, |
| CallExpr* CE, SVal L, |
| ExplodedNode<GRState>* Pred) { |
| |
| RetainSummary* Summ = !isa<loc::FuncVal>(L) ? 0 |
| : Summaries.getSummary(cast<loc::FuncVal>(L).getDecl()); |
| |
| EvalSummary(Dst, Eng, Builder, CE, 0, Summ, |
| CE->arg_begin(), CE->arg_end(), Pred); |
| } |
| |
| void CFRefCount::EvalObjCMessageExpr(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Eng, |
| GRStmtNodeBuilder<GRState>& Builder, |
| ObjCMessageExpr* ME, |
| ExplodedNode<GRState>* Pred) { |
| RetainSummary* Summ; |
| |
| if (Expr* Receiver = ME->getReceiver()) { |
| // We need the type-information of the tracked receiver object |
| // Retrieve it from the state. |
| ObjCInterfaceDecl* ID = 0; |
| |
| // FIXME: Wouldn't it be great if this code could be reduced? It's just |
| // a chain of lookups. |
| const GRState* St = Builder.GetState(Pred); |
| SVal V = Eng.getStateManager().GetSValAsScalarOrLoc(St, Receiver); |
| |
| SymbolRef Sym = V.getAsLocSymbol(); |
| if (Sym) { |
| if (const RefVal* T = St->get<RefBindings>(Sym)) { |
| QualType Ty = T->getType(); |
| |
| if (const PointerType* PT = Ty->getAsPointerType()) { |
| QualType PointeeTy = PT->getPointeeType(); |
| |
| if (ObjCInterfaceType* IT = dyn_cast<ObjCInterfaceType>(PointeeTy)) |
| ID = IT->getDecl(); |
| } |
| } |
| } |
| |
| Summ = Summaries.getMethodSummary(ME, ID); |
| |
| // Special-case: are we sending a mesage to "self"? |
| // This is a hack. When we have full-IP this should be removed. |
| if (!Summ) { |
| ObjCMethodDecl* MD = |
| dyn_cast<ObjCMethodDecl>(&Eng.getGraph().getCodeDecl()); |
| |
| if (MD) { |
| if (Expr* Receiver = ME->getReceiver()) { |
| SVal X = Eng.getStateManager().GetSValAsScalarOrLoc(St, Receiver); |
| if (loc::MemRegionVal* L = dyn_cast<loc::MemRegionVal>(&X)) |
| if (L->getRegion() == Eng.getStateManager().getSelfRegion(St)) { |
| // Create a summmary where all of the arguments "StopTracking". |
| Summ = Summaries.getPersistentSummary(RetEffect::MakeNoRet(), |
| DoNothing, |
| StopTracking); |
| } |
| } |
| } |
| } |
| } |
| else |
| Summ = Summaries.getClassMethodSummary(ME->getClassName(), |
| ME->getSelector()); |
| |
| EvalSummary(Dst, Eng, Builder, ME, ME->getReceiver(), Summ, |
| ME->arg_begin(), ME->arg_end(), Pred); |
| } |
| |
| namespace { |
| class VISIBILITY_HIDDEN StopTrackingCallback : public SymbolVisitor { |
| GRStateRef state; |
| public: |
| StopTrackingCallback(GRStateRef st) : state(st) {} |
| GRStateRef getState() { return state; } |
| |
| bool VisitSymbol(SymbolRef sym) { |
| state = state.remove<RefBindings>(sym); |
| return true; |
| } |
| |
| const GRState* getState() const { return state.getState(); } |
| }; |
| } // end anonymous namespace |
| |
| |
| void CFRefCount::EvalBind(GRStmtNodeBuilderRef& B, SVal location, SVal val) { |
| // Are we storing to something that causes the value to "escape"? |
| bool escapes = false; |
| |
| // A value escapes in three possible cases (this may change): |
| // |
| // (1) we are binding to something that is not a memory region. |
| // (2) we are binding to a memregion that does not have stack storage |
| // (3) we are binding to a memregion with stack storage that the store |
| // does not understand. |
| GRStateRef state = B.getState(); |
| |
| if (!isa<loc::MemRegionVal>(location)) |
| escapes = true; |
| else { |
| const MemRegion* R = cast<loc::MemRegionVal>(location).getRegion(); |
| escapes = !B.getStateManager().hasStackStorage(R); |
| |
| if (!escapes) { |
| // To test (3), generate a new state with the binding removed. If it is |
| // the same state, then it escapes (since the store cannot represent |
| // the binding). |
| escapes = (state == (state.BindLoc(cast<Loc>(location), UnknownVal()))); |
| } |
| } |
| |
| // If our store can represent the binding and we aren't storing to something |
| // that doesn't have local storage then just return and have the simulation |
| // state continue as is. |
| if (!escapes) |
| return; |
| |
| // Otherwise, find all symbols referenced by 'val' that we are tracking |
| // and stop tracking them. |
| B.MakeNode(state.scanReachableSymbols<StopTrackingCallback>(val).getState()); |
| } |
| |
| std::pair<GRStateRef,bool> |
| CFRefCount::HandleSymbolDeath(GRStateManager& VMgr, |
| const GRState* St, const Decl* CD, |
| SymbolRef sid, |
| RefVal V, bool& hasLeak) { |
| |
| GRStateRef state(St, VMgr); |
| assert ((!V.isReturnedOwned() || CD) && |
| "CodeDecl must be available for reporting ReturnOwned errors."); |
| |
| if (V.isReturnedOwned() && V.getCount() == 0) |
| if (const ObjCMethodDecl* MD = dyn_cast<ObjCMethodDecl>(CD)) { |
| std::string s = MD->getSelector().getAsString(); |
| if (!followsReturnRule(s.c_str())) { |
| hasLeak = true; |
| state = state.set<RefBindings>(sid, V ^ RefVal::ErrorLeakReturned); |
| return std::make_pair(state, true); |
| } |
| } |
| |
| // All other cases. |
| |
| hasLeak = V.isOwned() || |
| ((V.isNotOwned() || V.isReturnedOwned()) && V.getCount() > 0); |
| |
| if (!hasLeak) |
| return std::make_pair(state.remove<RefBindings>(sid), false); |
| |
| return std::make_pair(state.set<RefBindings>(sid, V ^ RefVal::ErrorLeak), |
| false); |
| } |
| |
| |
| |
| // Dead symbols. |
| |
| |
| |
| // Return statements. |
| |
| void CFRefCount::EvalReturn(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Eng, |
| GRStmtNodeBuilder<GRState>& Builder, |
| ReturnStmt* S, |
| ExplodedNode<GRState>* Pred) { |
| |
| Expr* RetE = S->getRetValue(); |
| if (!RetE) |
| return; |
| |
| GRStateRef state(Builder.GetState(Pred), Eng.getStateManager()); |
| SymbolRef Sym = state.GetSValAsScalarOrLoc(RetE).getAsLocSymbol(); |
| |
| if (!Sym) |
| return; |
| |
| // Get the reference count binding (if any). |
| const RefVal* T = state.get<RefBindings>(Sym); |
| |
| if (!T) |
| return; |
| |
| // Change the reference count. |
| RefVal X = *T; |
| |
| switch (X.getKind()) { |
| case RefVal::Owned: { |
| unsigned cnt = X.getCount(); |
| assert (cnt > 0); |
| X = RefVal::makeReturnedOwned(cnt - 1); |
| break; |
| } |
| |
| case RefVal::NotOwned: { |
| unsigned cnt = X.getCount(); |
| X = cnt ? RefVal::makeReturnedOwned(cnt - 1) |
| : RefVal::makeReturnedNotOwned(); |
| break; |
| } |
| |
| default: |
| return; |
| } |
| |
| // Update the binding. |
| state = state.set<RefBindings>(Sym, X); |
| Builder.MakeNode(Dst, S, Pred, state); |
| } |
| |
| // Assumptions. |
| |
| const GRState* CFRefCount::EvalAssume(GRStateManager& VMgr, |
| const GRState* St, |
| SVal Cond, bool Assumption, |
| bool& isFeasible) { |
| |
| // FIXME: We may add to the interface of EvalAssume the list of symbols |
| // whose assumptions have changed. For now we just iterate through the |
| // bindings and check if any of the tracked symbols are NULL. This isn't |
| // too bad since the number of symbols we will track in practice are |
| // probably small and EvalAssume is only called at branches and a few |
| // other places. |
| RefBindings B = St->get<RefBindings>(); |
| |
| if (B.isEmpty()) |
| return St; |
| |
| bool changed = false; |
| |
| GRStateRef state(St, VMgr); |
| RefBindings::Factory& RefBFactory = state.get_context<RefBindings>(); |
| |
| for (RefBindings::iterator I=B.begin(), E=B.end(); I!=E; ++I) { |
| // Check if the symbol is null (or equal to any constant). |
| // If this is the case, stop tracking the symbol. |
| if (VMgr.getSymVal(St, I.getKey())) { |
| changed = true; |
| B = RefBFactory.Remove(B, I.getKey()); |
| } |
| } |
| |
| if (changed) |
| state = state.set<RefBindings>(B); |
| |
| return state; |
| } |
| |
| GRStateRef CFRefCount::Update(GRStateRef state, SymbolRef sym, |
| RefVal V, ArgEffect E, |
| RefVal::Kind& hasErr) { |
| |
| // In GC mode [... release] and [... retain] do nothing. |
| switch (E) { |
| default: break; |
| case IncRefMsg: E = isGCEnabled() ? DoNothing : IncRef; break; |
| case DecRefMsg: E = isGCEnabled() ? DoNothing : DecRef; break; |
| case MakeCollectable: E = isGCEnabled() ? DecRef : DoNothing; break; |
| case NewAutoreleasePool: E = isGCEnabled() ? DoNothing : |
| NewAutoreleasePool; break; |
| } |
| |
| // Handle all use-after-releases. |
| if (!isGCEnabled() && V.getKind() == RefVal::Released) { |
| V = V ^ RefVal::ErrorUseAfterRelease; |
| hasErr = V.getKind(); |
| return state.set<RefBindings>(sym, V); |
| } |
| |
| switch (E) { |
| default: |
| assert (false && "Unhandled CFRef transition."); |
| |
| case Dealloc: |
| // Any use of -dealloc in GC is *bad*. |
| if (isGCEnabled()) { |
| V = V ^ RefVal::ErrorDeallocGC; |
| hasErr = V.getKind(); |
| break; |
| } |
| |
| switch (V.getKind()) { |
| default: |
| assert(false && "Invalid case."); |
| case RefVal::Owned: |
| // The object immediately transitions to the released state. |
| V = V ^ RefVal::Released; |
| V.clearCounts(); |
| return state.set<RefBindings>(sym, V); |
| case RefVal::NotOwned: |
| V = V ^ RefVal::ErrorDeallocNotOwned; |
| hasErr = V.getKind(); |
| break; |
| } |
| break; |
| |
| case NewAutoreleasePool: |
| assert(!isGCEnabled()); |
| return state.add<AutoreleaseStack>(sym); |
| |
| case MayEscape: |
| if (V.getKind() == RefVal::Owned) { |
| V = V ^ RefVal::NotOwned; |
| break; |
| } |
| |
| // Fall-through. |
| |
| case DoNothingByRef: |
| case DoNothing: |
| return state; |
| |
| case Autorelease: |
| if (isGCEnabled()) |
| return state; |
| |
| // Update the autorelease counts. |
| state = SendAutorelease(state, ARCountFactory, sym); |
| |
| // Fall-through. |
| |
| case StopTracking: |
| return state.remove<RefBindings>(sym); |
| |
| case IncRef: |
| switch (V.getKind()) { |
| default: |
| assert(false); |
| |
| case RefVal::Owned: |
| case RefVal::NotOwned: |
| V = V + 1; |
| break; |
| case RefVal::Released: |
| // Non-GC cases are handled above. |
| assert(isGCEnabled()); |
| V = (V ^ RefVal::Owned) + 1; |
| break; |
| } |
| break; |
| |
| case SelfOwn: |
| V = V ^ RefVal::NotOwned; |
| // Fall-through. |
| case DecRef: |
| switch (V.getKind()) { |
| default: |
| // case 'RefVal::Released' handled above. |
| assert (false); |
| |
| case RefVal::Owned: |
| assert(V.getCount() > 0); |
| if (V.getCount() == 1) V = V ^ RefVal::Released; |
| V = V - 1; |
| break; |
| |
| case RefVal::NotOwned: |
| if (V.getCount() > 0) |
| V = V - 1; |
| else { |
| V = V ^ RefVal::ErrorReleaseNotOwned; |
| hasErr = V.getKind(); |
| } |
| break; |
| |
| case RefVal::Released: |
| // Non-GC cases are handled above. |
| assert(isGCEnabled()); |
| V = V ^ RefVal::ErrorUseAfterRelease; |
| hasErr = V.getKind(); |
| break; |
| } |
| break; |
| } |
| return state.set<RefBindings>(sym, V); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Error reporting. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| |
| //===-------------===// |
| // Bug Descriptions. // |
| //===-------------===// |
| |
| class VISIBILITY_HIDDEN CFRefBug : public BugType { |
| protected: |
| CFRefCount& TF; |
| |
| CFRefBug(CFRefCount* tf, const char* name) |
| : BugType(name, "Memory (Core Foundation/Objective-C)"), TF(*tf) {} |
| public: |
| |
| CFRefCount& getTF() { return TF; } |
| const CFRefCount& getTF() const { return TF; } |
| |
| // FIXME: Eventually remove. |
| virtual const char* getDescription() const = 0; |
| |
| virtual bool isLeak() const { return false; } |
| }; |
| |
| class VISIBILITY_HIDDEN UseAfterRelease : public CFRefBug { |
| public: |
| UseAfterRelease(CFRefCount* tf) |
| : CFRefBug(tf, "Use-after-release") {} |
| |
| const char* getDescription() const { |
| return "Reference-counted object is used after it is released"; |
| } |
| }; |
| |
| class VISIBILITY_HIDDEN BadRelease : public CFRefBug { |
| public: |
| BadRelease(CFRefCount* tf) : CFRefBug(tf, "bad release") {} |
| |
| const char* getDescription() const { |
| return "Incorrect decrement of the reference count of a " |
| "Core Foundation object (" |
| "the object is not owned at this point by the caller)"; |
| } |
| }; |
| |
| class VISIBILITY_HIDDEN DeallocGC : public CFRefBug { |
| public: |
| DeallocGC(CFRefCount *tf) : CFRefBug(tf, |
| "-dealloc called while using GC") {} |
| |
| const char *getDescription() const { |
| return "-dealloc called while using GC"; |
| } |
| }; |
| |
| class VISIBILITY_HIDDEN DeallocNotOwned : public CFRefBug { |
| public: |
| DeallocNotOwned(CFRefCount *tf) : CFRefBug(tf, |
| "-dealloc sent to non-exclusively owned object") {} |
| |
| const char *getDescription() const { |
| return "-dealloc sent to object that may be referenced elsewhere"; |
| } |
| }; |
| |
| class VISIBILITY_HIDDEN Leak : public CFRefBug { |
| const bool isReturn; |
| protected: |
| Leak(CFRefCount* tf, const char* name, bool isRet) |
| : CFRefBug(tf, name), isReturn(isRet) {} |
| public: |
| |
| const char* getDescription() const { return ""; } |
| |
| bool isLeak() const { return true; } |
| }; |
| |
| class VISIBILITY_HIDDEN LeakAtReturn : public Leak { |
| public: |
| LeakAtReturn(CFRefCount* tf, const char* name) |
| : Leak(tf, name, true) {} |
| }; |
| |
| class VISIBILITY_HIDDEN LeakWithinFunction : public Leak { |
| public: |
| LeakWithinFunction(CFRefCount* tf, const char* name) |
| : Leak(tf, name, false) {} |
| }; |
| |
| //===---------===// |
| // Bug Reports. // |
| //===---------===// |
| |
| class VISIBILITY_HIDDEN CFRefReport : public RangedBugReport { |
| protected: |
| SymbolRef Sym; |
| const CFRefCount &TF; |
| public: |
| CFRefReport(CFRefBug& D, const CFRefCount &tf, |
| ExplodedNode<GRState> *n, SymbolRef sym) |
| : RangedBugReport(D, D.getDescription(), n), Sym(sym), TF(tf) {} |
| |
| virtual ~CFRefReport() {} |
| |
| CFRefBug& getBugType() { |
| return (CFRefBug&) RangedBugReport::getBugType(); |
| } |
| const CFRefBug& getBugType() const { |
| return (const CFRefBug&) RangedBugReport::getBugType(); |
| } |
| |
| virtual void getRanges(BugReporter& BR, const SourceRange*& beg, |
| const SourceRange*& end) { |
| |
| if (!getBugType().isLeak()) |
| RangedBugReport::getRanges(BR, beg, end); |
| else |
| beg = end = 0; |
| } |
| |
| SymbolRef getSymbol() const { return Sym; } |
| |
| PathDiagnosticPiece* getEndPath(BugReporter& BR, |
| const ExplodedNode<GRState>* N); |
| |
| std::pair<const char**,const char**> getExtraDescriptiveText(); |
| |
| PathDiagnosticPiece* VisitNode(const ExplodedNode<GRState>* N, |
| const ExplodedNode<GRState>* PrevN, |
| const ExplodedGraph<GRState>& G, |
| BugReporter& BR, |
| NodeResolver& NR); |
| }; |
| |
| class VISIBILITY_HIDDEN CFRefLeakReport : public CFRefReport { |
| SourceLocation AllocSite; |
| const MemRegion* AllocBinding; |
| public: |
| CFRefLeakReport(CFRefBug& D, const CFRefCount &tf, |
| ExplodedNode<GRState> *n, SymbolRef sym, |
| GRExprEngine& Eng); |
| |
| PathDiagnosticPiece* getEndPath(BugReporter& BR, |
| const ExplodedNode<GRState>* N); |
| |
| SourceLocation getLocation() const { return AllocSite; } |
| }; |
| } // end anonymous namespace |
| |
| void CFRefCount::RegisterChecks(BugReporter& BR) { |
| useAfterRelease = new UseAfterRelease(this); |
| BR.Register(useAfterRelease); |
| |
| releaseNotOwned = new BadRelease(this); |
| BR.Register(releaseNotOwned); |
| |
| deallocGC = new DeallocGC(this); |
| BR.Register(deallocGC); |
| |
| deallocNotOwned = new DeallocNotOwned(this); |
| BR.Register(deallocNotOwned); |
| |
| // First register "return" leaks. |
| const char* name = 0; |
| |
| if (isGCEnabled()) |
| name = "Leak of returned object when using garbage collection"; |
| else if (getLangOptions().getGCMode() == LangOptions::HybridGC) |
| name = "Leak of returned object when not using garbage collection (GC) in " |
| "dual GC/non-GC code"; |
| else { |
| assert(getLangOptions().getGCMode() == LangOptions::NonGC); |
| name = "Leak of returned object"; |
| } |
| |
| leakAtReturn = new LeakAtReturn(this, name); |
| BR.Register(leakAtReturn); |
| |
| // Second, register leaks within a function/method. |
| if (isGCEnabled()) |
| name = "Leak of object when using garbage collection"; |
| else if (getLangOptions().getGCMode() == LangOptions::HybridGC) |
| name = "Leak of object when not using garbage collection (GC) in " |
| "dual GC/non-GC code"; |
| else { |
| assert(getLangOptions().getGCMode() == LangOptions::NonGC); |
| name = "Leak"; |
| } |
| |
| leakWithinFunction = new LeakWithinFunction(this, name); |
| BR.Register(leakWithinFunction); |
| |
| // Save the reference to the BugReporter. |
| this->BR = &BR; |
| } |
| |
| static const char* Msgs[] = { |
| // GC only |
| "Code is compiled to only use garbage collection", |
| // No GC. |
| "Code is compiled to use reference counts", |
| // Hybrid, with GC. |
| "Code is compiled to use either garbage collection (GC) or reference counts" |
| " (non-GC). The bug occurs with GC enabled", |
| // Hybrid, without GC |
| "Code is compiled to use either garbage collection (GC) or reference counts" |
| " (non-GC). The bug occurs in non-GC mode" |
| }; |
| |
| std::pair<const char**,const char**> CFRefReport::getExtraDescriptiveText() { |
| CFRefCount& TF = static_cast<CFRefBug&>(getBugType()).getTF(); |
| |
| switch (TF.getLangOptions().getGCMode()) { |
| default: |
| assert(false); |
| |
| case LangOptions::GCOnly: |
| assert (TF.isGCEnabled()); |
| return std::make_pair(&Msgs[0], &Msgs[0]+1); |
| |
| case LangOptions::NonGC: |
| assert (!TF.isGCEnabled()); |
| return std::make_pair(&Msgs[1], &Msgs[1]+1); |
| |
| case LangOptions::HybridGC: |
| if (TF.isGCEnabled()) |
| return std::make_pair(&Msgs[2], &Msgs[2]+1); |
| else |
| return std::make_pair(&Msgs[3], &Msgs[3]+1); |
| } |
| } |
| |
| static inline bool contains(const llvm::SmallVectorImpl<ArgEffect>& V, |
| ArgEffect X) { |
| for (llvm::SmallVectorImpl<ArgEffect>::const_iterator I=V.begin(), E=V.end(); |
| I!=E; ++I) |
| if (*I == X) return true; |
| |
| return false; |
| } |
| |
| PathDiagnosticPiece* CFRefReport::VisitNode(const ExplodedNode<GRState>* N, |
| const ExplodedNode<GRState>* PrevN, |
| const ExplodedGraph<GRState>& G, |
| BugReporter& BR, |
| NodeResolver& NR) { |
| |
| // Check if the type state has changed. |
| GRStateManager &StMgr = cast<GRBugReporter>(BR).getStateManager(); |
| GRStateRef PrevSt(PrevN->getState(), StMgr); |
| GRStateRef CurrSt(N->getState(), StMgr); |
| |
| const RefVal* CurrT = CurrSt.get<RefBindings>(Sym); |
| if (!CurrT) return NULL; |
| |
| const RefVal& CurrV = *CurrT; |
| const RefVal* PrevT = PrevSt.get<RefBindings>(Sym); |
| |
| // Create a string buffer to constain all the useful things we want |
| // to tell the user. |
| std::string sbuf; |
| llvm::raw_string_ostream os(sbuf); |
| |
| // This is the allocation site since the previous node had no bindings |
| // for this symbol. |
| if (!PrevT) { |
| Stmt* S = cast<PostStmt>(N->getLocation()).getStmt(); |
| |
| if (CallExpr *CE = dyn_cast<CallExpr>(S)) { |
| // Get the name of the callee (if it is available). |
| SVal X = CurrSt.GetSValAsScalarOrLoc(CE->getCallee()); |
| if (loc::FuncVal* FV = dyn_cast<loc::FuncVal>(&X)) |
| os << "Call to function '" << FV->getDecl()->getNameAsString() <<'\''; |
| else |
| os << "function call"; |
| } |
| else { |
| assert (isa<ObjCMessageExpr>(S)); |
| os << "Method"; |
| } |
| |
| if (CurrV.getObjKind() == RetEffect::CF) { |
| os << " returns a Core Foundation object with a "; |
| } |
| else { |
| assert (CurrV.getObjKind() == RetEffect::ObjC); |
| os << " returns an Objective-C object with a "; |
| } |
| |
| if (CurrV.isOwned()) { |
| os << "+1 retain count (owning reference)."; |
| |
| if (static_cast<CFRefBug&>(getBugType()).getTF().isGCEnabled()) { |
| assert(CurrV.getObjKind() == RetEffect::CF); |
| os << " " |
| "Core Foundation objects are not automatically garbage collected."; |
| } |
| } |
| else { |
| assert (CurrV.isNotOwned()); |
| os << "+0 retain count (non-owning reference)."; |
| } |
| |
| PathDiagnosticLocation Pos(S, BR.getContext().getSourceManager()); |
| return new PathDiagnosticEventPiece(Pos, os.str()); |
| } |
| |
| // Gather up the effects that were performed on the object at this |
| // program point |
| llvm::SmallVector<ArgEffect, 2> AEffects; |
| |
| if (const RetainSummary *Summ = TF.getSummaryOfNode(NR.getOriginalNode(N))) { |
| // We only have summaries attached to nodes after evaluating CallExpr and |
| // ObjCMessageExprs. |
| Stmt* S = cast<PostStmt>(N->getLocation()).getStmt(); |
| |
| if (CallExpr *CE = dyn_cast<CallExpr>(S)) { |
| // Iterate through the parameter expressions and see if the symbol |
| // was ever passed as an argument. |
| unsigned i = 0; |
| |
| for (CallExpr::arg_iterator AI=CE->arg_begin(), AE=CE->arg_end(); |
| AI!=AE; ++AI, ++i) { |
| |
| // Retrieve the value of the argument. Is it the symbol |
| // we are interested in? |
| if (CurrSt.GetSValAsScalarOrLoc(*AI).getAsLocSymbol() != Sym) |
| continue; |
| |
| // We have an argument. Get the effect! |
| AEffects.push_back(Summ->getArg(i)); |
| } |
| } |
| else if (ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(S)) { |
| if (Expr *receiver = ME->getReceiver()) |
| if (CurrSt.GetSValAsScalarOrLoc(receiver).getAsLocSymbol() == Sym) { |
| // The symbol we are tracking is the receiver. |
| AEffects.push_back(Summ->getReceiverEffect()); |
| } |
| } |
| } |
| |
| do { |
| // Get the previous type state. |
| RefVal PrevV = *PrevT; |
| |
| // Specially handle -dealloc. |
| if (!TF.isGCEnabled() && contains(AEffects, Dealloc)) { |
| // Determine if the object's reference count was pushed to zero. |
| assert(!(PrevV == CurrV) && "The typestate *must* have changed."); |
| // We may not have transitioned to 'release' if we hit an error. |
| // This case is handled elsewhere. |
| if (CurrV.getKind() == RefVal::Released) { |
| assert(CurrV.getCount() == 0); |
| os << "Object released by directly sending the '-dealloc' message"; |
| break; |
| } |
| } |
| |
| // Specially handle CFMakeCollectable and friends. |
| if (contains(AEffects, MakeCollectable)) { |
| // Get the name of the function. |
| Stmt* S = cast<PostStmt>(N->getLocation()).getStmt(); |
| loc::FuncVal FV = |
| cast<loc::FuncVal>(CurrSt.GetSValAsScalarOrLoc(cast<CallExpr>(S)->getCallee())); |
| const std::string& FName = FV.getDecl()->getNameAsString(); |
| |
| if (TF.isGCEnabled()) { |
| // Determine if the object's reference count was pushed to zero. |
| assert(!(PrevV == CurrV) && "The typestate *must* have changed."); |
| |
| os << "In GC mode a call to '" << FName |
| << "' decrements an object's retain count and registers the " |
| "object with the garbage collector. "; |
| |
| if (CurrV.getKind() == RefVal::Released) { |
| assert(CurrV.getCount() == 0); |
| os << "Since it now has a 0 retain count the object can be " |
| "automatically collected by the garbage collector."; |
| } |
| else |
| os << "An object must have a 0 retain count to be garbage collected. " |
| "After this call its retain count is +" << CurrV.getCount() |
| << '.'; |
| } |
| else |
| os << "When GC is not enabled a call to '" << FName |
| << "' has no effect on its argument."; |
| |
| // Nothing more to say. |
| break; |
| } |
| |
| // Determine if the typestate has changed. |
| if (!(PrevV == CurrV)) |
| switch (CurrV.getKind()) { |
| case RefVal::Owned: |
| case RefVal::NotOwned: |
| |
| if (PrevV.getCount() == CurrV.getCount()) |
| return 0; |
| |
| if (PrevV.getCount() > CurrV.getCount()) |
| os << "Reference count decremented."; |
| else |
| os << "Reference count incremented."; |
| |
| if (unsigned Count = CurrV.getCount()) |
| os << " The object now has a +" << Count << " retain count."; |
| |
| if (PrevV.getKind() == RefVal::Released) { |
| assert(TF.isGCEnabled() && CurrV.getCount() > 0); |
| os << " The object is not eligible for garbage collection until the " |
| "retain count reaches 0 again."; |
| } |
| |
| break; |
| |
| case RefVal::Released: |
| os << "Object released."; |
| break; |
| |
| case RefVal::ReturnedOwned: |
| os << "Object returned to caller as an owning reference (single retain " |
| "count transferred to caller)."; |
| break; |
| |
| case RefVal::ReturnedNotOwned: |
| os << "Object returned to caller with a +0 (non-owning) retain count."; |
| break; |
| |
| default: |
| return NULL; |
| } |
| |
| // Emit any remaining diagnostics for the argument effects (if any). |
| for (llvm::SmallVectorImpl<ArgEffect>::iterator I=AEffects.begin(), |
| E=AEffects.end(); I != E; ++I) { |
| |
| // A bunch of things have alternate behavior under GC. |
| if (TF.isGCEnabled()) |
| switch (*I) { |
| default: break; |
| case Autorelease: |
| os << "In GC mode an 'autorelease' has no effect."; |
| continue; |
| case IncRefMsg: |
| os << "In GC mode the 'retain' message has no effect."; |
| continue; |
| case DecRefMsg: |
| os << "In GC mode the 'release' message has no effect."; |
| continue; |
| } |
| } |
| } while(0); |
| |
| if (os.str().empty()) |
| return 0; // We have nothing to say! |
| |
| Stmt* S = cast<PostStmt>(N->getLocation()).getStmt(); |
| PathDiagnosticLocation Pos(S, BR.getContext().getSourceManager()); |
| PathDiagnosticPiece* P = new PathDiagnosticEventPiece(Pos, os.str()); |
| |
| // Add the range by scanning the children of the statement for any bindings |
| // to Sym. |
| for (Stmt::child_iterator I = S->child_begin(), E = S->child_end(); I!=E; ++I) |
| if (Expr* Exp = dyn_cast_or_null<Expr>(*I)) |
| if (CurrSt.GetSValAsScalarOrLoc(Exp).getAsLocSymbol() == Sym) { |
| P->addRange(Exp->getSourceRange()); |
| break; |
| } |
| |
| return P; |
| } |
| |
| namespace { |
| class VISIBILITY_HIDDEN FindUniqueBinding : |
| public StoreManager::BindingsHandler { |
| SymbolRef Sym; |
| const MemRegion* Binding; |
| bool First; |
| |
| public: |
| FindUniqueBinding(SymbolRef sym) : Sym(sym), Binding(0), First(true) {} |
| |
| bool HandleBinding(StoreManager& SMgr, Store store, const MemRegion* R, |
| SVal val) { |
| |
| SymbolRef SymV = val.getAsSymbol(); |
| if (!SymV || SymV != Sym) |
| return true; |
| |
| if (Binding) { |
| First = false; |
| return false; |
| } |
| else |
| Binding = R; |
| |
| return true; |
| } |
| |
| operator bool() { return First && Binding; } |
| const MemRegion* getRegion() { return Binding; } |
| }; |
| } |
| |
| static std::pair<const ExplodedNode<GRState>*,const MemRegion*> |
| GetAllocationSite(GRStateManager& StateMgr, const ExplodedNode<GRState>* N, |
| SymbolRef Sym) { |
| |
| // Find both first node that referred to the tracked symbol and the |
| // memory location that value was store to. |
| const ExplodedNode<GRState>* Last = N; |
| const MemRegion* FirstBinding = 0; |
| |
| while (N) { |
| const GRState* St = N->getState(); |
| RefBindings B = St->get<RefBindings>(); |
| |
| if (!B.lookup(Sym)) |
| break; |
| |
| FindUniqueBinding FB(Sym); |
| StateMgr.iterBindings(St, FB); |
| if (FB) FirstBinding = FB.getRegion(); |
| |
| Last = N; |
| N = N->pred_empty() ? NULL : *(N->pred_begin()); |
| } |
| |
| return std::make_pair(Last, FirstBinding); |
| } |
| |
| PathDiagnosticPiece* |
| CFRefReport::getEndPath(BugReporter& br, const ExplodedNode<GRState>* EndN) { |
| // Tell the BugReporter to report cases when the tracked symbol is |
| // assigned to different variables, etc. |
| GRBugReporter& BR = cast<GRBugReporter>(br); |
| cast<GRBugReporter>(BR).addNotableSymbol(Sym); |
| return RangedBugReport::getEndPath(BR, EndN); |
| } |
| |
| PathDiagnosticPiece* |
| CFRefLeakReport::getEndPath(BugReporter& br, const ExplodedNode<GRState>* EndN){ |
| |
| GRBugReporter& BR = cast<GRBugReporter>(br); |
| // Tell the BugReporter to report cases when the tracked symbol is |
| // assigned to different variables, etc. |
| cast<GRBugReporter>(BR).addNotableSymbol(Sym); |
| |
| // We are reporting a leak. Walk up the graph to get to the first node where |
| // the symbol appeared, and also get the first VarDecl that tracked object |
| // is stored to. |
| const ExplodedNode<GRState>* AllocNode = 0; |
| const MemRegion* FirstBinding = 0; |
| |
| llvm::tie(AllocNode, FirstBinding) = |
| GetAllocationSite(BR.getStateManager(), EndN, Sym); |
| |
| // Get the allocate site. |
| assert(AllocNode); |
| Stmt* FirstStmt = cast<PostStmt>(AllocNode->getLocation()).getStmt(); |
| |
| SourceManager& SMgr = BR.getContext().getSourceManager(); |
| unsigned AllocLine =SMgr.getInstantiationLineNumber(FirstStmt->getLocStart()); |
| |
| // Compute an actual location for the leak. Sometimes a leak doesn't |
| // occur at an actual statement (e.g., transition between blocks; end |
| // of function) so we need to walk the graph and compute a real location. |
| const ExplodedNode<GRState>* LeakN = EndN; |
| PathDiagnosticLocation L; |
| |
| while (LeakN) { |
| ProgramPoint P = LeakN->getLocation(); |
| |
| if (const PostStmt *PS = dyn_cast<PostStmt>(&P)) { |
| L = PathDiagnosticLocation(PS->getStmt()->getLocStart(), SMgr); |
| break; |
| } |
| else if (const BlockEdge *BE = dyn_cast<BlockEdge>(&P)) { |
| if (const Stmt* Term = BE->getSrc()->getTerminator()) { |
| L = PathDiagnosticLocation(Term->getLocStart(), SMgr); |
| break; |
| } |
| } |
| |
| LeakN = LeakN->succ_empty() ? 0 : *(LeakN->succ_begin()); |
| } |
| |
| if (!L.isValid()) { |
| CompoundStmt *CS = BR.getStateManager().getCodeDecl().getBody(); |
| L = PathDiagnosticLocation(CS->getRBracLoc(), SMgr); |
| } |
| |
| std::string sbuf; |
| llvm::raw_string_ostream os(sbuf); |
| |
| os << "Object allocated on line " << AllocLine; |
| |
| if (FirstBinding) |
| os << " and stored into '" << FirstBinding->getString() << '\''; |
| |
| // Get the retain count. |
| const RefVal* RV = EndN->getState()->get<RefBindings>(Sym); |
| |
| if (RV->getKind() == RefVal::ErrorLeakReturned) { |
| // FIXME: Per comments in rdar://6320065, "create" only applies to CF |
| // ojbects. Only "copy", "alloc", "retain" and "new" transfer ownership |
| // to the caller for NS objects. |
| ObjCMethodDecl& MD = cast<ObjCMethodDecl>(BR.getGraph().getCodeDecl()); |
| os << " is returned from a method whose name ('" |
| << MD.getSelector().getAsString() |
| << "') does not contain 'copy' or otherwise starts with" |
| " 'new' or 'alloc'. This violates the naming convention rules given" |
| " in the Memory Management Guide for Cocoa (object leaked)."; |
| } |
| else |
| os << " is no longer referenced after this point and has a retain count of" |
| " +" |
| << RV->getCount() << " (object leaked)."; |
| |
| return new PathDiagnosticEventPiece(L, os.str()); |
| } |
| |
| |
| CFRefLeakReport::CFRefLeakReport(CFRefBug& D, const CFRefCount &tf, |
| ExplodedNode<GRState> *n, |
| SymbolRef sym, GRExprEngine& Eng) |
| : CFRefReport(D, tf, n, sym) |
| { |
| |
| // Most bug reports are cached at the location where they occured. |
| // With leaks, we want to unique them by the location where they were |
| // allocated, and only report a single path. To do this, we need to find |
| // the allocation site of a piece of tracked memory, which we do via a |
| // call to GetAllocationSite. This will walk the ExplodedGraph backwards. |
| // Note that this is *not* the trimmed graph; we are guaranteed, however, |
| // that all ancestor nodes that represent the allocation site have the |
| // same SourceLocation. |
| const ExplodedNode<GRState>* AllocNode = 0; |
| |
| llvm::tie(AllocNode, AllocBinding) = // Set AllocBinding. |
| GetAllocationSite(Eng.getStateManager(), getEndNode(), getSymbol()); |
| |
| // Get the SourceLocation for the allocation site. |
| ProgramPoint P = AllocNode->getLocation(); |
| AllocSite = cast<PostStmt>(P).getStmt()->getLocStart(); |
| |
| // Fill in the description of the bug. |
| Description.clear(); |
| llvm::raw_string_ostream os(Description); |
| SourceManager& SMgr = Eng.getContext().getSourceManager(); |
| unsigned AllocLine = SMgr.getInstantiationLineNumber(AllocSite); |
| os << "Potential leak of object allocated on line " << AllocLine; |
| |
| // FIXME: AllocBinding doesn't get populated for RegionStore yet. |
| if (AllocBinding) |
| os << " and stored into '" << AllocBinding->getString() << '\''; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Handle dead symbols and end-of-path. |
| //===----------------------------------------------------------------------===// |
| |
| void CFRefCount::EvalEndPath(GRExprEngine& Eng, |
| GREndPathNodeBuilder<GRState>& Builder) { |
| |
| const GRState* St = Builder.getState(); |
| RefBindings B = St->get<RefBindings>(); |
| |
| llvm::SmallVector<std::pair<SymbolRef, bool>, 10> Leaked; |
| const Decl* CodeDecl = &Eng.getGraph().getCodeDecl(); |
| |
| for (RefBindings::iterator I = B.begin(), E = B.end(); I != E; ++I) { |
| bool hasLeak = false; |
| |
| std::pair<GRStateRef, bool> X = |
| HandleSymbolDeath(Eng.getStateManager(), St, CodeDecl, |
| (*I).first, (*I).second, hasLeak); |
| |
| St = X.first; |
| if (hasLeak) Leaked.push_back(std::make_pair((*I).first, X.second)); |
| } |
| |
| if (Leaked.empty()) |
| return; |
| |
| ExplodedNode<GRState>* N = Builder.MakeNode(St); |
| |
| if (!N) |
| return; |
| |
| for (llvm::SmallVector<std::pair<SymbolRef,bool>, 10>::iterator |
| I = Leaked.begin(), E = Leaked.end(); I != E; ++I) { |
| |
| CFRefBug *BT = static_cast<CFRefBug*>(I->second ? leakAtReturn |
| : leakWithinFunction); |
| assert(BT && "BugType not initialized."); |
| CFRefLeakReport* report = new CFRefLeakReport(*BT, *this, N, I->first, Eng); |
| BR->EmitReport(report); |
| } |
| } |
| |
| void CFRefCount::EvalDeadSymbols(ExplodedNodeSet<GRState>& Dst, |
| GRExprEngine& Eng, |
| GRStmtNodeBuilder<GRState>& Builder, |
| ExplodedNode<GRState>* Pred, |
| Stmt* S, |
| const GRState* St, |
| SymbolReaper& SymReaper) { |
| |
| // FIXME: a lot of copy-and-paste from EvalEndPath. Refactor. |
| RefBindings B = St->get<RefBindings>(); |
| llvm::SmallVector<std::pair<SymbolRef,bool>, 10> Leaked; |
| |
| for (SymbolReaper::dead_iterator I = SymReaper.dead_begin(), |
| E = SymReaper.dead_end(); I != E; ++I) { |
| |
| const RefVal* T = B.lookup(*I); |
| if (!T) continue; |
| |
| bool hasLeak = false; |
| |
| std::pair<GRStateRef, bool> X |
| = HandleSymbolDeath(Eng.getStateManager(), St, 0, *I, *T, hasLeak); |
| |
| St = X.first; |
| |
| if (hasLeak) |
| Leaked.push_back(std::make_pair(*I,X.second)); |
| } |
| |
| if (!Leaked.empty()) { |
| // Create a new intermediate node representing the leak point. We |
| // use a special program point that represents this checker-specific |
| // transition. We use the address of RefBIndex as a unique tag for this |
| // checker. We will create another node (if we don't cache out) that |
| // removes the retain-count bindings from the state. |
| // NOTE: We use 'generateNode' so that it does interplay with the |
| // auto-transition logic. |
| ExplodedNode<GRState>* N = |
| Builder.generateNode(PostStmtCustom(S, &LeakProgramPointTag), St, Pred); |
| |
| if (!N) |
| return; |
| |
| // Generate the bug reports. |
| for (llvm::SmallVectorImpl<std::pair<SymbolRef,bool> >::iterator |
| I = Leaked.begin(), E = Leaked.end(); I != E; ++I) { |
| |
| CFRefBug *BT = static_cast<CFRefBug*>(I->second ? leakAtReturn |
| : leakWithinFunction); |
| assert(BT && "BugType not initialized."); |
| CFRefLeakReport* report = new CFRefLeakReport(*BT, *this, N, |
| I->first, Eng); |
| BR->EmitReport(report); |
| } |
| |
| Pred = N; |
| } |
| |
| // Now generate a new node that nukes the old bindings. |
| GRStateRef state(St, Eng.getStateManager()); |
| RefBindings::Factory& F = state.get_context<RefBindings>(); |
| |
| for (SymbolReaper::dead_iterator I = SymReaper.dead_begin(), |
| E = SymReaper.dead_end(); I!=E; ++I) |
| B = F.Remove(B, *I); |
| |
| state = state.set<RefBindings>(B); |
| Builder.MakeNode(Dst, S, Pred, state); |
| } |
| |
| void CFRefCount::ProcessNonLeakError(ExplodedNodeSet<GRState>& Dst, |
| GRStmtNodeBuilder<GRState>& Builder, |
| Expr* NodeExpr, Expr* ErrorExpr, |
| ExplodedNode<GRState>* Pred, |
| const GRState* St, |
| RefVal::Kind hasErr, SymbolRef Sym) { |
| Builder.BuildSinks = true; |
| GRExprEngine::NodeTy* N = Builder.MakeNode(Dst, NodeExpr, Pred, St); |
| |
| if (!N) return; |
| |
| CFRefBug *BT = 0; |
| |
| switch (hasErr) { |
| default: |
| assert(false && "Unhandled error."); |
| return; |
| case RefVal::ErrorUseAfterRelease: |
| BT = static_cast<CFRefBug*>(useAfterRelease); |
| break; |
| case RefVal::ErrorReleaseNotOwned: |
| BT = static_cast<CFRefBug*>(releaseNotOwned); |
| break; |
| case RefVal::ErrorDeallocGC: |
| BT = static_cast<CFRefBug*>(deallocGC); |
| break; |
| case RefVal::ErrorDeallocNotOwned: |
| BT = static_cast<CFRefBug*>(deallocNotOwned); |
| break; |
| } |
| |
| CFRefReport *report = new CFRefReport(*BT, *this, N, Sym); |
| report->addRange(ErrorExpr->getSourceRange()); |
| BR->EmitReport(report); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Transfer function creation for external clients. |
| //===----------------------------------------------------------------------===// |
| |
| GRTransferFuncs* clang::MakeCFRefCountTF(ASTContext& Ctx, bool GCEnabled, |
| const LangOptions& lopts) { |
| return new CFRefCount(Ctx, GCEnabled, lopts); |
| } |