| //== RetainSummaryManager.cpp - Summaries for reference counting --*- 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 summaries implementation for retain counting, which |
| // implements a reference count checker for Core Foundation, Cocoa |
| // and OSObject (on Mac OS X). |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/StaticAnalyzer/Core/RetainSummaryManager.h" |
| #include "clang/Analysis/DomainSpecific/CocoaConventions.h" |
| #include "clang/AST/Attr.h" |
| #include "clang/AST/DeclCXX.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/ParentMap.h" |
| #include "clang/ASTMatchers/ASTMatchFinder.h" |
| |
| using namespace clang; |
| using namespace ento; |
| |
| template <class T> |
| constexpr static bool isOneOf() { |
| return false; |
| } |
| |
| /// Helper function to check whether the class is one of the |
| /// rest of varargs. |
| template <class T, class P, class... ToCompare> |
| constexpr static bool isOneOf() { |
| return std::is_same<T, P>::value || isOneOf<T, ToCompare...>(); |
| } |
| |
| template <class T> bool RetainSummaryManager::isAttrEnabled() { |
| if (isOneOf<T, CFConsumedAttr, CFReturnsRetainedAttr, |
| CFReturnsNotRetainedAttr, NSConsumedAttr, NSConsumesSelfAttr, |
| NSReturnsAutoreleasedAttr, NSReturnsRetainedAttr, |
| NSReturnsNotRetainedAttr>()) { |
| return TrackObjCAndCFObjects; |
| } else if (isOneOf<T, OSConsumedAttr, OSConsumesThisAttr, |
| OSReturnsNotRetainedAttr, OSReturnsRetainedAttr>()) { |
| return TrackOSObjects; |
| } |
| llvm_unreachable("Unexpected attribute passed"); |
| } |
| |
| ArgEffects RetainSummaryManager::getArgEffects() { |
| ArgEffects AE = ScratchArgs; |
| ScratchArgs = AF.getEmptyMap(); |
| return AE; |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getPersistentSummary(const RetainSummary &OldSumm) { |
| // Unique "simple" summaries -- those without ArgEffects. |
| if (OldSumm.isSimple()) { |
| ::llvm::FoldingSetNodeID ID; |
| OldSumm.Profile(ID); |
| |
| void *Pos; |
| CachedSummaryNode *N = SimpleSummaries.FindNodeOrInsertPos(ID, Pos); |
| |
| if (!N) { |
| N = (CachedSummaryNode *) BPAlloc.Allocate<CachedSummaryNode>(); |
| new (N) CachedSummaryNode(OldSumm); |
| SimpleSummaries.InsertNode(N, Pos); |
| } |
| |
| return &N->getValue(); |
| } |
| |
| RetainSummary *Summ = (RetainSummary *) BPAlloc.Allocate<RetainSummary>(); |
| new (Summ) RetainSummary(OldSumm); |
| return Summ; |
| } |
| |
| static bool isSubclass(const Decl *D, |
| StringRef ClassName) { |
| using namespace ast_matchers; |
| DeclarationMatcher SubclassM = cxxRecordDecl(isSameOrDerivedFrom(ClassName)); |
| return !(match(SubclassM, *D, D->getASTContext()).empty()); |
| } |
| |
| static bool isOSObjectSubclass(const Decl *D) { |
| return isSubclass(D, "OSObject"); |
| } |
| |
| static bool isOSObjectDynamicCast(StringRef S) { |
| return S == "safeMetaCast"; |
| } |
| |
| static bool isOSIteratorSubclass(const Decl *D) { |
| return isSubclass(D, "OSIterator"); |
| } |
| |
| static bool hasRCAnnotation(const Decl *D, StringRef rcAnnotation) { |
| for (const auto *Ann : D->specific_attrs<AnnotateAttr>()) { |
| if (Ann->getAnnotation() == rcAnnotation) |
| return true; |
| } |
| return false; |
| } |
| |
| static bool isRetain(const FunctionDecl *FD, StringRef FName) { |
| return FName.startswith_lower("retain") || FName.endswith_lower("retain"); |
| } |
| |
| static bool isRelease(const FunctionDecl *FD, StringRef FName) { |
| return FName.startswith_lower("release") || FName.endswith_lower("release"); |
| } |
| |
| static bool isAutorelease(const FunctionDecl *FD, StringRef FName) { |
| return FName.startswith_lower("autorelease") || |
| FName.endswith_lower("autorelease"); |
| } |
| |
| static bool isMakeCollectable(StringRef FName) { |
| return FName.contains_lower("MakeCollectable"); |
| } |
| |
| /// A function is OSObject related if it is declared on a subclass |
| /// of OSObject, or any of the parameters is a subclass of an OSObject. |
| static bool isOSObjectRelated(const CXXMethodDecl *MD) { |
| if (isOSObjectSubclass(MD->getParent())) |
| return true; |
| |
| for (ParmVarDecl *Param : MD->parameters()) { |
| QualType PT = Param->getType()->getPointeeType(); |
| if (!PT.isNull()) |
| if (CXXRecordDecl *RD = PT->getAsCXXRecordDecl()) |
| if (isOSObjectSubclass(RD)) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getSummaryForOSObject(const FunctionDecl *FD, |
| StringRef FName, QualType RetTy) { |
| if (RetTy->isPointerType()) { |
| const CXXRecordDecl *PD = RetTy->getPointeeType()->getAsCXXRecordDecl(); |
| if (PD && isOSObjectSubclass(PD)) { |
| if (const IdentifierInfo *II = FD->getIdentifier()) { |
| if (isOSObjectDynamicCast(II->getName())) |
| return getDefaultSummary(); |
| |
| // All objects returned with functions *not* starting with |
| // get, or iterators, are returned at +1. |
| if ((!II->getName().startswith("get") && |
| !II->getName().startswith("Get")) || |
| isOSIteratorSubclass(PD)) { |
| return getOSSummaryCreateRule(FD); |
| } else { |
| return getOSSummaryGetRule(FD); |
| } |
| } |
| } |
| } |
| |
| if (const auto *MD = dyn_cast<CXXMethodDecl>(FD)) { |
| const CXXRecordDecl *Parent = MD->getParent(); |
| if (TrackOSObjects && Parent && isOSObjectSubclass(Parent)) { |
| if (FName == "release") |
| return getOSSummaryReleaseRule(FD); |
| |
| if (FName == "retain") |
| return getOSSummaryRetainRule(FD); |
| |
| if (FName == "free") |
| return getOSSummaryFreeRule(FD); |
| |
| if (MD->getOverloadedOperator() == OO_New) |
| return getOSSummaryCreateRule(MD); |
| } |
| } |
| |
| return nullptr; |
| } |
| |
| const RetainSummary *RetainSummaryManager::getSummaryForObjCOrCFObject( |
| const FunctionDecl *FD, |
| StringRef FName, |
| QualType RetTy, |
| const FunctionType *FT, |
| bool &AllowAnnotations) { |
| |
| std::string RetTyName = RetTy.getAsString(); |
| |
| // FIXME: This should all be refactored into a chain of "summary lookup" |
| // filters. |
| assert(ScratchArgs.isEmpty()); |
| if (FName == "pthread_create" || FName == "pthread_setspecific") { |
| // Part of: <rdar://problem/7299394> and <rdar://problem/11282706>. |
| // This will be addressed better with IPA. |
| return getPersistentStopSummary(); |
| } else if(FName == "NSMakeCollectable") { |
| // Handle: id NSMakeCollectable(CFTypeRef) |
| AllowAnnotations = false; |
| return RetTy->isObjCIdType() ? getUnarySummary(FT, cfmakecollectable) |
| : getPersistentStopSummary(); |
| } else if (FName == "CFPlugInInstanceCreate") { |
| return getPersistentSummary(RetEffect::MakeNoRet()); |
| } else if (FName == "IORegistryEntrySearchCFProperty" || |
| (RetTyName == "CFMutableDictionaryRef" && |
| (FName == "IOBSDNameMatching" || FName == "IOServiceMatching" || |
| FName == "IOServiceNameMatching" || |
| FName == "IORegistryEntryIDMatching" || |
| FName == "IOOpenFirmwarePathMatching"))) { |
| // Part of <rdar://problem/6961230>. (IOKit) |
| // This should be addressed using a API table. |
| return getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF), DoNothing, |
| DoNothing); |
| } else if (FName == "IOServiceGetMatchingService" || |
| FName == "IOServiceGetMatchingServices") { |
| // 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. |
| ScratchArgs = AF.add(ScratchArgs, 1, DecRef); |
| return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); |
| } else if (FName == "IOServiceAddNotification" || |
| FName == "IOServiceAddMatchingNotification") { |
| // Part of <rdar://problem/6961230>. (IOKit) |
| // This should be addressed using a API table. |
| ScratchArgs = AF.add(ScratchArgs, 2, DecRef); |
| return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); |
| } else if (FName == "CVPixelBufferCreateWithBytes") { |
| // FIXES: <rdar://problem/7283567> |
| // Eventually this can be improved by recognizing that the pixel |
| // buffer passed to CVPixelBufferCreateWithBytes is released via |
| // a callback and doing full IPA to make sure this is done correctly. |
| // FIXME: This function has an out parameter that returns an |
| // allocated object. |
| ScratchArgs = AF.add(ScratchArgs, 7, StopTracking); |
| return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); |
| } else if (FName == "CGBitmapContextCreateWithData") { |
| // FIXES: <rdar://problem/7358899> |
| // Eventually this can be improved by recognizing that 'releaseInfo' |
| // passed to CGBitmapContextCreateWithData is released via |
| // a callback and doing full IPA to make sure this is done correctly. |
| ScratchArgs = AF.add(ScratchArgs, 8, StopTracking); |
| return getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF), DoNothing, |
| DoNothing); |
| } else if (FName == "CVPixelBufferCreateWithPlanarBytes") { |
| // FIXES: <rdar://problem/7283567> |
| // Eventually this can be improved by recognizing that the pixel |
| // buffer passed to CVPixelBufferCreateWithPlanarBytes is released |
| // via a callback and doing full IPA to make sure this is done |
| // correctly. |
| ScratchArgs = AF.add(ScratchArgs, 12, StopTracking); |
| return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); |
| } else if (FName == "VTCompressionSessionEncodeFrame") { |
| // The context argument passed to VTCompressionSessionEncodeFrame() |
| // is passed to the callback specified when creating the session |
| // (e.g. with VTCompressionSessionCreate()) which can release it. |
| // To account for this possibility, conservatively stop tracking |
| // the context. |
| ScratchArgs = AF.add(ScratchArgs, 5, StopTracking); |
| return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); |
| } else if (FName == "dispatch_set_context" || |
| FName == "xpc_connection_set_context") { |
| // <rdar://problem/11059275> - The analyzer currently doesn't have |
| // a good way to reason about the finalizer function for libdispatch. |
| // If we pass a context object that is memory managed, stop tracking it. |
| // <rdar://problem/13783514> - Same problem, but for XPC. |
| // FIXME: this hack should possibly go away once we can handle |
| // libdispatch and XPC finalizers. |
| ScratchArgs = AF.add(ScratchArgs, 1, StopTracking); |
| return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); |
| } else if (FName.startswith("NSLog")) { |
| return getDoNothingSummary(); |
| } else if (FName.startswith("NS") && |
| (FName.find("Insert") != StringRef::npos)) { |
| // Whitelist NSXXInsertXX, for example NSMapInsertIfAbsent, since they can |
| // be deallocated by NSMapRemove. (radar://11152419) |
| ScratchArgs = AF.add(ScratchArgs, 1, StopTracking); |
| ScratchArgs = AF.add(ScratchArgs, 2, StopTracking); |
| return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); |
| } |
| |
| if (RetTy->isPointerType()) { |
| |
| // For CoreFoundation ('CF') types. |
| if (cocoa::isRefType(RetTy, "CF", FName)) { |
| if (isRetain(FD, FName)) { |
| // CFRetain isn't supposed to be annotated. However, this may as |
| // well be a user-made "safe" CFRetain function that is incorrectly |
| // annotated as cf_returns_retained due to lack of better options. |
| // We want to ignore such annotation. |
| AllowAnnotations = false; |
| |
| return getUnarySummary(FT, cfretain); |
| } else if (isAutorelease(FD, FName)) { |
| // The headers use cf_consumed, but we can fully model CFAutorelease |
| // ourselves. |
| AllowAnnotations = false; |
| |
| return getUnarySummary(FT, cfautorelease); |
| } else if (isMakeCollectable(FName)) { |
| AllowAnnotations = false; |
| return getUnarySummary(FT, cfmakecollectable); |
| } else { |
| return getCFCreateGetRuleSummary(FD); |
| } |
| } |
| |
| // For CoreGraphics ('CG') and CoreVideo ('CV') types. |
| if (cocoa::isRefType(RetTy, "CG", FName) || |
| cocoa::isRefType(RetTy, "CV", FName)) { |
| if (isRetain(FD, FName)) |
| return getUnarySummary(FT, cfretain); |
| else |
| return getCFCreateGetRuleSummary(FD); |
| } |
| |
| // For all other CF-style types, use the Create/Get |
| // rule for summaries but don't support Retain functions |
| // with framework-specific prefixes. |
| if (coreFoundation::isCFObjectRef(RetTy)) { |
| return getCFCreateGetRuleSummary(FD); |
| } |
| |
| if (FD->hasAttr<CFAuditedTransferAttr>()) { |
| return getCFCreateGetRuleSummary(FD); |
| } |
| } |
| |
| // Check for release functions, the only kind of functions that we care |
| // about that don't return a pointer type. |
| if (FName.startswith("CG") || FName.startswith("CF")) { |
| // Test for 'CGCF'. |
| FName = FName.substr(FName.startswith("CGCF") ? 4 : 2); |
| |
| if (isRelease(FD, FName)) |
| return getUnarySummary(FT, cfrelease); |
| else { |
| assert(ScratchArgs.isEmpty()); |
| // 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", "AddValue", |
| // "AppendValue", or "SetAttribute", then we assume that arguments may |
| // "escape." This means that something else holds on to the object, |
| // allowing it be used even after its local retain count drops to 0. |
| ArgEffect E = (StrInStrNoCase(FName, "InsertValue") != StringRef::npos || |
| StrInStrNoCase(FName, "AddValue") != StringRef::npos || |
| StrInStrNoCase(FName, "SetValue") != StringRef::npos || |
| StrInStrNoCase(FName, "AppendValue") != StringRef::npos || |
| StrInStrNoCase(FName, "SetAttribute") != StringRef::npos) |
| ? MayEscape |
| : DoNothing; |
| |
| return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, E); |
| } |
| } |
| |
| return nullptr; |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::generateSummary(const FunctionDecl *FD, |
| bool &AllowAnnotations) { |
| // We generate "stop" summaries for implicitly defined functions. |
| if (FD->isImplicit()) |
| return getPersistentStopSummary(); |
| |
| const IdentifierInfo *II = FD->getIdentifier(); |
| |
| StringRef FName = II ? II->getName() : ""; |
| |
| // Strip away preceding '_'. Doing this here will effect all the checks |
| // down below. |
| FName = FName.substr(FName.find_first_not_of('_')); |
| |
| // Inspect the result type. Strip away any typedefs. |
| const auto *FT = FD->getType()->getAs<FunctionType>(); |
| QualType RetTy = FT->getReturnType(); |
| |
| if (TrackOSObjects) |
| if (const RetainSummary *S = getSummaryForOSObject(FD, FName, RetTy)) |
| return S; |
| |
| if (TrackObjCAndCFObjects) |
| if (const RetainSummary *S = |
| getSummaryForObjCOrCFObject(FD, FName, RetTy, FT, AllowAnnotations)) |
| return S; |
| |
| if (const auto *MD = dyn_cast<CXXMethodDecl>(FD)) |
| if (!(TrackOSObjects && isOSObjectRelated(MD))) |
| return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, StopTracking, |
| DoNothing); |
| |
| return getDefaultSummary(); |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getFunctionSummary(const FunctionDecl *FD) { |
| // If we don't know what function we're calling, use our default summary. |
| if (!FD) |
| return getDefaultSummary(); |
| |
| // 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. |
| bool AllowAnnotations = true; |
| const RetainSummary *S = generateSummary(FD, AllowAnnotations); |
| |
| // Annotations override defaults. |
| if (AllowAnnotations) |
| updateSummaryFromAnnotations(S, FD); |
| |
| FuncSummaries[FD] = S; |
| return S; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Summary creation for functions (largely uses of Core Foundation). |
| //===----------------------------------------------------------------------===// |
| |
| static ArgEffect getStopTrackingHardEquivalent(ArgEffect E) { |
| switch (E) { |
| case DoNothing: |
| case Autorelease: |
| case DecRefBridgedTransferred: |
| case IncRef: |
| case IncRefMsg: |
| case MakeCollectable: |
| case UnretainedOutParameter: |
| case RetainedOutParameter: |
| case MayEscape: |
| case StopTracking: |
| case StopTrackingHard: |
| return StopTrackingHard; |
| case DecRef: |
| case DecRefAndStopTrackingHard: |
| return DecRefAndStopTrackingHard; |
| case DecRefMsg: |
| case DecRefMsgAndStopTrackingHard: |
| return DecRefMsgAndStopTrackingHard; |
| case Dealloc: |
| return Dealloc; |
| } |
| |
| llvm_unreachable("Unknown ArgEffect kind"); |
| } |
| |
| void RetainSummaryManager::updateSummaryForCall(const RetainSummary *&S, |
| const CallEvent &Call) { |
| if (Call.hasNonZeroCallbackArg()) { |
| ArgEffect RecEffect = |
| getStopTrackingHardEquivalent(S->getReceiverEffect()); |
| ArgEffect DefEffect = |
| getStopTrackingHardEquivalent(S->getDefaultArgEffect()); |
| |
| ArgEffects CustomArgEffects = S->getArgEffects(); |
| for (ArgEffects::iterator I = CustomArgEffects.begin(), |
| E = CustomArgEffects.end(); |
| I != E; ++I) { |
| ArgEffect Translated = getStopTrackingHardEquivalent(I->second); |
| if (Translated != DefEffect) |
| ScratchArgs = AF.add(ScratchArgs, I->first, Translated); |
| } |
| |
| RetEffect RE = RetEffect::MakeNoRetHard(); |
| |
| // Special cases where the callback argument CANNOT free the return value. |
| // This can generally only happen if we know that the callback will only be |
| // called when the return value is already being deallocated. |
| if (const SimpleFunctionCall *FC = dyn_cast<SimpleFunctionCall>(&Call)) { |
| if (IdentifierInfo *Name = FC->getDecl()->getIdentifier()) { |
| // When the CGBitmapContext is deallocated, the callback here will free |
| // the associated data buffer. |
| // The callback in dispatch_data_create frees the buffer, but not |
| // the data object. |
| if (Name->isStr("CGBitmapContextCreateWithData") || |
| Name->isStr("dispatch_data_create")) |
| RE = S->getRetEffect(); |
| } |
| } |
| |
| S = getPersistentSummary(RE, RecEffect, DefEffect); |
| } |
| |
| // Special case '[super init];' and '[self init];' |
| // |
| // Even though calling '[super init]' without assigning the result to self |
| // and checking if the parent returns 'nil' is a bad pattern, it is common. |
| // Additionally, our Self Init checker already warns about it. To avoid |
| // overwhelming the user with messages from both checkers, we model the case |
| // of '[super init]' in cases when it is not consumed by another expression |
| // as if the call preserves the value of 'self'; essentially, assuming it can |
| // never fail and return 'nil'. |
| // Note, we don't want to just stop tracking the value since we want the |
| // RetainCount checker to report leaks and use-after-free if SelfInit checker |
| // is turned off. |
| if (const ObjCMethodCall *MC = dyn_cast<ObjCMethodCall>(&Call)) { |
| if (MC->getMethodFamily() == OMF_init && MC->isReceiverSelfOrSuper()) { |
| |
| // Check if the message is not consumed, we know it will not be used in |
| // an assignment, ex: "self = [super init]". |
| const Expr *ME = MC->getOriginExpr(); |
| const LocationContext *LCtx = MC->getLocationContext(); |
| ParentMap &PM = LCtx->getAnalysisDeclContext()->getParentMap(); |
| if (!PM.isConsumedExpr(ME)) { |
| RetainSummaryTemplate ModifiableSummaryTemplate(S, *this); |
| ModifiableSummaryTemplate->setReceiverEffect(DoNothing); |
| ModifiableSummaryTemplate->setRetEffect(RetEffect::MakeNoRet()); |
| } |
| } |
| } |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getSummary(const CallEvent &Call, |
| QualType ReceiverType) { |
| const RetainSummary *Summ; |
| switch (Call.getKind()) { |
| case CE_Function: |
| case CE_CXXMember: |
| case CE_CXXMemberOperator: |
| case CE_CXXConstructor: |
| case CE_CXXAllocator: |
| Summ = getFunctionSummary(cast_or_null<FunctionDecl>(Call.getDecl())); |
| break; |
| case CE_Block: |
| case CE_CXXDestructor: |
| // FIXME: These calls are currently unsupported. |
| return getPersistentStopSummary(); |
| case CE_ObjCMessage: { |
| const ObjCMethodCall &Msg = cast<ObjCMethodCall>(Call); |
| if (Msg.isInstanceMessage()) |
| Summ = getInstanceMethodSummary(Msg, ReceiverType); |
| else |
| Summ = getClassMethodSummary(Msg); |
| break; |
| } |
| } |
| |
| updateSummaryForCall(Summ, Call); |
| |
| assert(Summ && "Unknown call type?"); |
| return Summ; |
| } |
| |
| |
| const RetainSummary * |
| RetainSummaryManager::getCFCreateGetRuleSummary(const FunctionDecl *FD) { |
| if (coreFoundation::followsCreateRule(FD)) |
| return getCFSummaryCreateRule(FD); |
| |
| return getCFSummaryGetRule(FD); |
| } |
| |
| bool RetainSummaryManager::isTrustedReferenceCountImplementation( |
| const FunctionDecl *FD) { |
| return hasRCAnnotation(FD, "rc_ownership_trusted_implementation"); |
| } |
| |
| Optional<RetainSummaryManager::BehaviorSummary> |
| RetainSummaryManager::canEval(const CallExpr *CE, const FunctionDecl *FD, |
| bool &hasTrustedImplementationAnnotation) { |
| |
| IdentifierInfo *II = FD->getIdentifier(); |
| if (!II) |
| return None; |
| |
| StringRef FName = II->getName(); |
| FName = FName.substr(FName.find_first_not_of('_')); |
| |
| QualType ResultTy = CE->getCallReturnType(Ctx); |
| if (ResultTy->isObjCIdType()) { |
| if (II->isStr("NSMakeCollectable")) |
| return BehaviorSummary::Identity; |
| } else if (ResultTy->isPointerType()) { |
| // Handle: (CF|CG|CV)Retain |
| // CFAutorelease |
| // It's okay to be a little sloppy here. |
| if (cocoa::isRefType(ResultTy, "CF", FName) || |
| cocoa::isRefType(ResultTy, "CG", FName) || |
| cocoa::isRefType(ResultTy, "CV", FName)) |
| if (isRetain(FD, FName) || isAutorelease(FD, FName) || |
| isMakeCollectable(FName)) |
| return BehaviorSummary::Identity; |
| |
| // safeMetaCast is called by OSDynamicCast. |
| // We assume that OSDynamicCast is either an identity (cast is OK, |
| // the input was non-zero), |
| // or that it returns zero (when the cast failed, or the input |
| // was zero). |
| if (TrackOSObjects && isOSObjectDynamicCast(FName)) { |
| return BehaviorSummary::IdentityOrZero; |
| } |
| |
| const FunctionDecl* FDD = FD->getDefinition(); |
| if (FDD && isTrustedReferenceCountImplementation(FDD)) { |
| hasTrustedImplementationAnnotation = true; |
| return BehaviorSummary::Identity; |
| } |
| } |
| |
| if (const auto *MD = dyn_cast<CXXMethodDecl>(FD)) { |
| const CXXRecordDecl *Parent = MD->getParent(); |
| if (TrackOSObjects && Parent && isOSObjectSubclass(Parent)) |
| if (FName == "release" || FName == "retain") |
| return BehaviorSummary::NoOp; |
| } |
| |
| return None; |
| } |
| |
| const 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->getNumParams() != 1) |
| return getPersistentStopSummary(); |
| |
| assert (ScratchArgs.isEmpty()); |
| |
| ArgEffect Effect; |
| switch (func) { |
| case cfretain: Effect = IncRef; break; |
| case cfrelease: Effect = DecRef; break; |
| case cfautorelease: Effect = Autorelease; break; |
| case cfmakecollectable: Effect = MakeCollectable; break; |
| } |
| |
| ScratchArgs = AF.add(ScratchArgs, 0, Effect); |
| return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getOSSummaryRetainRule(const FunctionDecl *FD) { |
| return getPersistentSummary(RetEffect::MakeNoRet(), |
| /*ReceiverEff=*/DoNothing, |
| /*DefaultEff=*/DoNothing, |
| /*ThisEff=*/IncRef); |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getOSSummaryReleaseRule(const FunctionDecl *FD) { |
| return getPersistentSummary(RetEffect::MakeNoRet(), |
| /*ReceiverEff=*/DoNothing, |
| /*DefaultEff=*/DoNothing, |
| /*ThisEff=*/DecRef); |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getOSSummaryFreeRule(const FunctionDecl *FD) { |
| return getPersistentSummary(RetEffect::MakeNoRet(), |
| /*ReceiverEff=*/DoNothing, |
| /*DefaultEff=*/DoNothing, |
| /*ThisEff=*/Dealloc); |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getOSSummaryCreateRule(const FunctionDecl *FD) { |
| return getPersistentSummary(RetEffect::MakeOwned(RetEffect::OS)); |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getOSSummaryGetRule(const FunctionDecl *FD) { |
| return getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::OS)); |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getCFSummaryCreateRule(const FunctionDecl *FD) { |
| assert (ScratchArgs.isEmpty()); |
| |
| return getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF)); |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getCFSummaryGetRule(const FunctionDecl *FD) { |
| assert (ScratchArgs.isEmpty()); |
| return getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::CF), |
| DoNothing, DoNothing); |
| } |
| |
| |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Summary creation for Selectors. |
| //===----------------------------------------------------------------------===// |
| |
| Optional<RetEffect> |
| RetainSummaryManager::getRetEffectFromAnnotations(QualType RetTy, |
| const Decl *D) { |
| if (TrackObjCAndCFObjects && cocoa::isCocoaObjectRef(RetTy)) { |
| if (D->hasAttr<NSReturnsRetainedAttr>()) |
| return ObjCAllocRetE; |
| |
| if (D->hasAttr<NSReturnsNotRetainedAttr>() || |
| D->hasAttr<NSReturnsAutoreleasedAttr>()) |
| return RetEffect::MakeNotOwned(RetEffect::ObjC); |
| |
| } else if (!RetTy->isPointerType()) { |
| return None; |
| } |
| |
| if (hasEnabledAttr<CFReturnsRetainedAttr>(D)) { |
| return RetEffect::MakeOwned(RetEffect::CF); |
| } else if (hasEnabledAttr<OSReturnsRetainedAttr>(D)) { |
| return RetEffect::MakeOwned(RetEffect::OS); |
| } else if (hasRCAnnotation(D, "rc_ownership_returns_retained")) { |
| return RetEffect::MakeOwned(RetEffect::Generalized); |
| } |
| |
| if (hasEnabledAttr<CFReturnsNotRetainedAttr>(D)) { |
| return RetEffect::MakeNotOwned(RetEffect::CF); |
| } else if (hasEnabledAttr<OSReturnsNotRetainedAttr>(D)) { |
| return RetEffect::MakeNotOwned(RetEffect::OS); |
| } else if (hasRCAnnotation(D, "rc_ownership_returns_not_retained")) { |
| return RetEffect::MakeNotOwned(RetEffect::Generalized); |
| } |
| |
| if (const auto *MD = dyn_cast<CXXMethodDecl>(D)) |
| for (const auto *PD : MD->overridden_methods()) |
| if (auto RE = getRetEffectFromAnnotations(RetTy, PD)) |
| return RE; |
| |
| return None; |
| } |
| |
| bool RetainSummaryManager::applyFunctionParamAnnotationEffect(const ParmVarDecl *pd, |
| unsigned parm_idx, |
| const FunctionDecl *FD, |
| ArgEffects::Factory &AF, |
| RetainSummaryTemplate &Template) { |
| if (hasEnabledAttr<NSConsumedAttr>(pd)) { |
| Template->addArg(AF, parm_idx, DecRefMsg); |
| return true; |
| } else if (hasEnabledAttr<CFConsumedAttr>(pd) || |
| hasEnabledAttr<OSConsumedAttr>(pd) || |
| hasRCAnnotation(pd, "rc_ownership_consumed")) { |
| Template->addArg(AF, parm_idx, DecRef); |
| return true; |
| } else if (hasEnabledAttr<CFReturnsRetainedAttr>(pd) || |
| hasRCAnnotation(pd, "rc_ownership_returns_retained")) { |
| QualType PointeeTy = pd->getType()->getPointeeType(); |
| if (!PointeeTy.isNull()) { |
| if (coreFoundation::isCFObjectRef(PointeeTy)) { |
| Template->addArg(AF, parm_idx, RetainedOutParameter); |
| return true; |
| } |
| } |
| } else if (hasEnabledAttr<CFReturnsNotRetainedAttr>(pd)) { |
| QualType PointeeTy = pd->getType()->getPointeeType(); |
| if (!PointeeTy.isNull()) { |
| if (coreFoundation::isCFObjectRef(PointeeTy)) { |
| Template->addArg(AF, parm_idx, UnretainedOutParameter); |
| return true; |
| } |
| } |
| } else { |
| if (const auto *MD = dyn_cast<CXXMethodDecl>(FD)) { |
| for (const auto *OD : MD->overridden_methods()) { |
| const ParmVarDecl *OP = OD->parameters()[parm_idx]; |
| if (applyFunctionParamAnnotationEffect(OP, parm_idx, OD, AF, Template)) |
| return true; |
| } |
| } |
| } |
| |
| return false; |
| } |
| |
| void |
| RetainSummaryManager::updateSummaryFromAnnotations(const RetainSummary *&Summ, |
| const FunctionDecl *FD) { |
| if (!FD) |
| return; |
| |
| assert(Summ && "Must have a summary to add annotations to."); |
| RetainSummaryTemplate Template(Summ, *this); |
| |
| // Effects on the parameters. |
| unsigned parm_idx = 0; |
| for (auto pi = FD->param_begin(), |
| pe = FD->param_end(); pi != pe; ++pi, ++parm_idx) { |
| const ParmVarDecl *pd = *pi; |
| applyFunctionParamAnnotationEffect(pd, parm_idx, FD, AF, Template); |
| } |
| |
| QualType RetTy = FD->getReturnType(); |
| if (Optional<RetEffect> RetE = getRetEffectFromAnnotations(RetTy, FD)) |
| Template->setRetEffect(*RetE); |
| |
| if (hasEnabledAttr<OSConsumesThisAttr>(FD)) |
| Template->setThisEffect(DecRef); |
| } |
| |
| void |
| RetainSummaryManager::updateSummaryFromAnnotations(const RetainSummary *&Summ, |
| const ObjCMethodDecl *MD) { |
| if (!MD) |
| return; |
| |
| assert(Summ && "Must have a valid summary to add annotations to"); |
| RetainSummaryTemplate Template(Summ, *this); |
| |
| // Effects on the receiver. |
| if (MD->hasAttr<NSConsumesSelfAttr>()) |
| Template->setReceiverEffect(DecRefMsg); |
| |
| // Effects on the parameters. |
| unsigned parm_idx = 0; |
| for (auto pi=MD->param_begin(), pe=MD->param_end(); |
| pi != pe; ++pi, ++parm_idx) { |
| const ParmVarDecl *pd = *pi; |
| if (pd->hasAttr<NSConsumedAttr>()) { |
| Template->addArg(AF, parm_idx, DecRefMsg); |
| } else if (pd->hasAttr<CFConsumedAttr>() || pd->hasAttr<OSConsumedAttr>()) { |
| Template->addArg(AF, parm_idx, DecRef); |
| } else if (pd->hasAttr<CFReturnsRetainedAttr>()) { |
| QualType PointeeTy = pd->getType()->getPointeeType(); |
| if (!PointeeTy.isNull()) |
| if (coreFoundation::isCFObjectRef(PointeeTy)) |
| Template->addArg(AF, parm_idx, RetainedOutParameter); |
| } else if (pd->hasAttr<CFReturnsNotRetainedAttr>()) { |
| QualType PointeeTy = pd->getType()->getPointeeType(); |
| if (!PointeeTy.isNull()) |
| if (coreFoundation::isCFObjectRef(PointeeTy)) |
| Template->addArg(AF, parm_idx, UnretainedOutParameter); |
| } |
| } |
| |
| QualType RetTy = MD->getReturnType(); |
| if (Optional<RetEffect> RetE = getRetEffectFromAnnotations(RetTy, MD)) |
| Template->setRetEffect(*RetE); |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getStandardMethodSummary(const ObjCMethodDecl *MD, |
| Selector S, QualType RetTy) { |
| // Any special effects? |
| ArgEffect ReceiverEff = DoNothing; |
| RetEffect ResultEff = RetEffect::MakeNoRet(); |
| |
| // Check the method family, and apply any default annotations. |
| switch (MD ? MD->getMethodFamily() : S.getMethodFamily()) { |
| case OMF_None: |
| case OMF_initialize: |
| case OMF_performSelector: |
| // Assume all Objective-C methods follow Cocoa Memory Management rules. |
| // FIXME: Does the non-threaded performSelector family really belong here? |
| // The selector could be, say, @selector(copy). |
| if (cocoa::isCocoaObjectRef(RetTy)) |
| ResultEff = RetEffect::MakeNotOwned(RetEffect::ObjC); |
| else if (coreFoundation::isCFObjectRef(RetTy)) { |
| // ObjCMethodDecl currently doesn't consider CF objects as valid return |
| // values for alloc, new, copy, or mutableCopy, so we have to |
| // double-check with the selector. This is ugly, but there aren't that |
| // many Objective-C methods that return CF objects, right? |
| if (MD) { |
| switch (S.getMethodFamily()) { |
| case OMF_alloc: |
| case OMF_new: |
| case OMF_copy: |
| case OMF_mutableCopy: |
| ResultEff = RetEffect::MakeOwned(RetEffect::CF); |
| break; |
| default: |
| ResultEff = RetEffect::MakeNotOwned(RetEffect::CF); |
| break; |
| } |
| } else { |
| ResultEff = RetEffect::MakeNotOwned(RetEffect::CF); |
| } |
| } |
| break; |
| case OMF_init: |
| ResultEff = ObjCInitRetE; |
| ReceiverEff = DecRefMsg; |
| break; |
| case OMF_alloc: |
| case OMF_new: |
| case OMF_copy: |
| case OMF_mutableCopy: |
| if (cocoa::isCocoaObjectRef(RetTy)) |
| ResultEff = ObjCAllocRetE; |
| else if (coreFoundation::isCFObjectRef(RetTy)) |
| ResultEff = RetEffect::MakeOwned(RetEffect::CF); |
| break; |
| case OMF_autorelease: |
| ReceiverEff = Autorelease; |
| break; |
| case OMF_retain: |
| ReceiverEff = IncRefMsg; |
| break; |
| case OMF_release: |
| ReceiverEff = DecRefMsg; |
| break; |
| case OMF_dealloc: |
| ReceiverEff = Dealloc; |
| break; |
| case OMF_self: |
| // -self is handled specially by the ExprEngine to propagate the receiver. |
| break; |
| case OMF_retainCount: |
| case OMF_finalize: |
| // These methods don't return objects. |
| break; |
| } |
| |
| // If one of the arguments in the selector has the keyword 'delegate' we |
| // should stop tracking the reference count for the receiver. This is |
| // because the reference count is quite possibly handled by a delegate |
| // method. |
| if (S.isKeywordSelector()) { |
| for (unsigned i = 0, e = S.getNumArgs(); i != e; ++i) { |
| StringRef Slot = S.getNameForSlot(i); |
| if (Slot.substr(Slot.size() - 8).equals_lower("delegate")) { |
| if (ResultEff == ObjCInitRetE) |
| ResultEff = RetEffect::MakeNoRetHard(); |
| else |
| ReceiverEff = StopTrackingHard; |
| } |
| } |
| } |
| |
| if (ScratchArgs.isEmpty() && ReceiverEff == DoNothing && |
| ResultEff.getKind() == RetEffect::NoRet) |
| return getDefaultSummary(); |
| |
| return getPersistentSummary(ResultEff, ReceiverEff, MayEscape); |
| } |
| |
| const RetainSummary *RetainSummaryManager::getInstanceMethodSummary( |
| const ObjCMethodCall &Msg, QualType ReceiverType) { |
| const ObjCInterfaceDecl *ReceiverClass = nullptr; |
| |
| // We do better tracking of the type of the object than the core ExprEngine. |
| // See if we have its type in our private state. |
| if (!ReceiverType.isNull()) |
| if (const auto *PT = ReceiverType->getAs<ObjCObjectPointerType>()) |
| ReceiverClass = PT->getInterfaceDecl(); |
| |
| // If we don't know what kind of object this is, fall back to its static type. |
| if (!ReceiverClass) |
| ReceiverClass = Msg.getReceiverInterface(); |
| |
| // FIXME: The receiver could be a reference to a class, meaning that |
| // we should use the class method. |
| // id x = [NSObject class]; |
| // [x performSelector:... withObject:... afterDelay:...]; |
| Selector S = Msg.getSelector(); |
| const ObjCMethodDecl *Method = Msg.getDecl(); |
| if (!Method && ReceiverClass) |
| Method = ReceiverClass->getInstanceMethod(S); |
| |
| return getMethodSummary(S, ReceiverClass, Method, Msg.getResultType(), |
| ObjCMethodSummaries); |
| } |
| |
| const RetainSummary * |
| RetainSummaryManager::getMethodSummary(Selector S, const ObjCInterfaceDecl *ID, |
| const ObjCMethodDecl *MD, QualType RetTy, |
| ObjCMethodSummariesTy &CachedSummaries) { |
| |
| // Objective-C method summaries are only applicable to ObjC and CF objects. |
| if (!TrackObjCAndCFObjects) |
| return getDefaultSummary(); |
| |
| // Look up a summary in our summary cache. |
| const RetainSummary *Summ = CachedSummaries.find(ID, S); |
| |
| if (!Summ) { |
| Summ = getStandardMethodSummary(MD, S, RetTy); |
| |
| // Annotations override defaults. |
| updateSummaryFromAnnotations(Summ, MD); |
| |
| // Memoize the summary. |
| CachedSummaries[ObjCSummaryKey(ID, S)] = Summ; |
| } |
| |
| return Summ; |
| } |
| |
| void RetainSummaryManager::InitializeClassMethodSummaries() { |
| assert(ScratchArgs.isEmpty()); |
| // Create the [NSAssertionHandler currentHander] summary. |
| addClassMethSummary("NSAssertionHandler", "currentHandler", |
| getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::ObjC))); |
| |
| // Create the [NSAutoreleasePool addObject:] summary. |
| ScratchArgs = AF.add(ScratchArgs, 0, Autorelease); |
| addClassMethSummary("NSAutoreleasePool", "addObject", |
| getPersistentSummary(RetEffect::MakeNoRet(), |
| DoNothing, Autorelease)); |
| } |
| |
| void RetainSummaryManager::InitializeMethodSummaries() { |
| |
| assert (ScratchArgs.isEmpty()); |
| |
| // Create the "init" selector. It just acts as a pass-through for the |
| // receiver. |
| const RetainSummary *InitSumm = getPersistentSummary(ObjCInitRetE, DecRefMsg); |
| addNSObjectMethSummary(GetNullarySelector("init", Ctx), InitSumm); |
| |
| // awakeAfterUsingCoder: behaves basically like an 'init' method. It |
| // claims the receiver and returns a retained object. |
| addNSObjectMethSummary(GetUnarySelector("awakeAfterUsingCoder", Ctx), |
| InitSumm); |
| |
| // The next methods are allocators. |
| const RetainSummary *AllocSumm = getPersistentSummary(ObjCAllocRetE); |
| const RetainSummary *CFAllocSumm = |
| getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF)); |
| |
| // Create the "retain" selector. |
| RetEffect NoRet = RetEffect::MakeNoRet(); |
| const RetainSummary *Summ = getPersistentSummary(NoRet, IncRefMsg); |
| addNSObjectMethSummary(GetNullarySelector("retain", Ctx), Summ); |
| |
| // Create the "release" selector. |
| Summ = getPersistentSummary(NoRet, DecRefMsg); |
| addNSObjectMethSummary(GetNullarySelector("release", Ctx), Summ); |
| |
| // Create the -dealloc summary. |
| Summ = getPersistentSummary(NoRet, Dealloc); |
| addNSObjectMethSummary(GetNullarySelector("dealloc", Ctx), Summ); |
| |
| // Create the "autorelease" selector. |
| Summ = getPersistentSummary(NoRet, Autorelease); |
| addNSObjectMethSummary(GetNullarySelector("autorelease", Ctx), Summ); |
| |
| // 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. |
| const RetainSummary *NoTrackYet = getPersistentSummary(RetEffect::MakeNoRet(), |
| StopTracking, |
| StopTracking); |
| |
| addClassMethSummary("NSWindow", "alloc", NoTrackYet); |
| |
| // 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); |
| |
| // For NSNull, objects returned by +null are singletons that ignore |
| // retain/release semantics. Just don't track them. |
| // <rdar://problem/12858915> |
| addClassMethSummary("NSNull", "null", NoTrackYet); |
| |
| // Don't track allocated autorelease pools, as it is okay to prematurely |
| // exit a method. |
| addClassMethSummary("NSAutoreleasePool", "alloc", NoTrackYet); |
| addClassMethSummary("NSAutoreleasePool", "allocWithZone", NoTrackYet, false); |
| addClassMethSummary("NSAutoreleasePool", "new", NoTrackYet); |
| |
| // Create summaries QCRenderer/QCView -createSnapShotImageOfType: |
| addInstMethSummary("QCRenderer", AllocSumm, "createSnapshotImageOfType"); |
| addInstMethSummary("QCView", AllocSumm, "createSnapshotImageOfType"); |
| |
| // Create summaries for CIContext, 'createCGImage' and |
| // 'createCGLayerWithSize'. These objects are CF objects, and are not |
| // automatically garbage collected. |
| addInstMethSummary("CIContext", CFAllocSumm, "createCGImage", "fromRect"); |
| addInstMethSummary("CIContext", CFAllocSumm, "createCGImage", "fromRect", |
| "format", "colorSpace"); |
| addInstMethSummary("CIContext", CFAllocSumm, "createCGLayerWithSize", "info"); |
| } |
| |
| CallEffects CallEffects::getEffect(const ObjCMethodDecl *MD) { |
| ASTContext &Ctx = MD->getASTContext(); |
| LangOptions L = Ctx.getLangOpts(); |
| RetainSummaryManager M(Ctx, L.ObjCAutoRefCount, |
| /*TrackNSAndCFObjects=*/true, |
| /*TrackOSObjects=*/false); |
| const RetainSummary *S = M.getMethodSummary(MD); |
| CallEffects CE(S->getRetEffect()); |
| CE.Receiver = S->getReceiverEffect(); |
| unsigned N = MD->param_size(); |
| for (unsigned i = 0; i < N; ++i) { |
| CE.Args.push_back(S->getArg(i)); |
| } |
| return CE; |
| } |
| |
| CallEffects CallEffects::getEffect(const FunctionDecl *FD) { |
| ASTContext &Ctx = FD->getASTContext(); |
| LangOptions L = Ctx.getLangOpts(); |
| RetainSummaryManager M(Ctx, L.ObjCAutoRefCount, |
| /*TrackNSAndCFObjects=*/true, |
| /*TrackOSObjects=*/false); |
| const RetainSummary *S = M.getFunctionSummary(FD); |
| CallEffects CE(S->getRetEffect()); |
| unsigned N = FD->param_size(); |
| for (unsigned i = 0; i < N; ++i) { |
| CE.Args.push_back(S->getArg(i)); |
| } |
| return CE; |
| } |
