RetainCountChecker.cpp revision 73fa2525b4d8b9768dbc1e5a09976d6f9e568e23
1//==-- RetainCountChecker.cpp - Checks for leaks and other issues -*- C++ -*--// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file defines the methods for RetainCountChecker, which implements 11// a reference count checker for Core Foundation and Cocoa on (Mac OS X). 12// 13//===----------------------------------------------------------------------===// 14 15#include "ClangSACheckers.h" 16#include "clang/AST/Attr.h" 17#include "clang/AST/DeclCXX.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/ParentMap.h" 20#include "clang/Analysis/DomainSpecific/CocoaConventions.h" 21#include "clang/Basic/LangOptions.h" 22#include "clang/Basic/SourceManager.h" 23#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" 24#include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h" 25#include "clang/StaticAnalyzer/Core/Checker.h" 26#include "clang/StaticAnalyzer/Core/CheckerManager.h" 27#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" 28#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" 29#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h" 30#include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h" 31#include "clang/StaticAnalyzer/Checkers/ObjCRetainCount.h" 32#include "llvm/ADT/DenseMap.h" 33#include "llvm/ADT/FoldingSet.h" 34#include "llvm/ADT/ImmutableList.h" 35#include "llvm/ADT/ImmutableMap.h" 36#include "llvm/ADT/STLExtras.h" 37#include "llvm/ADT/SmallString.h" 38#include "llvm/ADT/StringExtras.h" 39#include <cstdarg> 40 41#include "AllocationDiagnostics.h" 42 43using namespace clang; 44using namespace ento; 45using namespace objc_retain; 46using llvm::StrInStrNoCase; 47 48//===----------------------------------------------------------------------===// 49// Adapters for FoldingSet. 50//===----------------------------------------------------------------------===// 51 52namespace llvm { 53template <> struct FoldingSetTrait<ArgEffect> { 54static inline void Profile(const ArgEffect X, FoldingSetNodeID &ID) { 55 ID.AddInteger((unsigned) X); 56} 57}; 58template <> struct FoldingSetTrait<RetEffect> { 59 static inline void Profile(const RetEffect &X, FoldingSetNodeID &ID) { 60 ID.AddInteger((unsigned) X.getKind()); 61 ID.AddInteger((unsigned) X.getObjKind()); 62} 63}; 64} // end llvm namespace 65 66//===----------------------------------------------------------------------===// 67// Reference-counting logic (typestate + counts). 68//===----------------------------------------------------------------------===// 69 70/// ArgEffects summarizes the effects of a function/method call on all of 71/// its arguments. 72typedef llvm::ImmutableMap<unsigned,ArgEffect> ArgEffects; 73 74namespace { 75class RefVal { 76public: 77 enum Kind { 78 Owned = 0, // Owning reference. 79 NotOwned, // Reference is not owned by still valid (not freed). 80 Released, // Object has been released. 81 ReturnedOwned, // Returned object passes ownership to caller. 82 ReturnedNotOwned, // Return object does not pass ownership to caller. 83 ERROR_START, 84 ErrorDeallocNotOwned, // -dealloc called on non-owned object. 85 ErrorDeallocGC, // Calling -dealloc with GC enabled. 86 ErrorUseAfterRelease, // Object used after released. 87 ErrorReleaseNotOwned, // Release of an object that was not owned. 88 ERROR_LEAK_START, 89 ErrorLeak, // A memory leak due to excessive reference counts. 90 ErrorLeakReturned, // A memory leak due to the returning method not having 91 // the correct naming conventions. 92 ErrorGCLeakReturned, 93 ErrorOverAutorelease, 94 ErrorReturnedNotOwned 95 }; 96 97private: 98 Kind kind; 99 RetEffect::ObjKind okind; 100 unsigned Cnt; 101 unsigned ACnt; 102 QualType T; 103 104 RefVal(Kind k, RetEffect::ObjKind o, unsigned cnt, unsigned acnt, QualType t) 105 : kind(k), okind(o), Cnt(cnt), ACnt(acnt), T(t) {} 106 107public: 108 Kind getKind() const { return kind; } 109 110 RetEffect::ObjKind getObjKind() const { return okind; } 111 112 unsigned getCount() const { return Cnt; } 113 unsigned getAutoreleaseCount() const { return ACnt; } 114 unsigned getCombinedCounts() const { return Cnt + ACnt; } 115 void clearCounts() { Cnt = 0; ACnt = 0; } 116 void setCount(unsigned i) { Cnt = i; } 117 void setAutoreleaseCount(unsigned i) { ACnt = i; } 118 119 QualType getType() const { return T; } 120 121 bool isOwned() const { 122 return getKind() == Owned; 123 } 124 125 bool isNotOwned() const { 126 return getKind() == NotOwned; 127 } 128 129 bool isReturnedOwned() const { 130 return getKind() == ReturnedOwned; 131 } 132 133 bool isReturnedNotOwned() const { 134 return getKind() == ReturnedNotOwned; 135 } 136 137 static RefVal makeOwned(RetEffect::ObjKind o, QualType t, 138 unsigned Count = 1) { 139 return RefVal(Owned, o, Count, 0, t); 140 } 141 142 static RefVal makeNotOwned(RetEffect::ObjKind o, QualType t, 143 unsigned Count = 0) { 144 return RefVal(NotOwned, o, Count, 0, t); 145 } 146 147 // Comparison, profiling, and pretty-printing. 148 149 bool operator==(const RefVal& X) const { 150 return kind == X.kind && Cnt == X.Cnt && T == X.T && ACnt == X.ACnt; 151 } 152 153 RefVal operator-(size_t i) const { 154 return RefVal(getKind(), getObjKind(), getCount() - i, 155 getAutoreleaseCount(), getType()); 156 } 157 158 RefVal operator+(size_t i) const { 159 return RefVal(getKind(), getObjKind(), getCount() + i, 160 getAutoreleaseCount(), getType()); 161 } 162 163 RefVal operator^(Kind k) const { 164 return RefVal(k, getObjKind(), getCount(), getAutoreleaseCount(), 165 getType()); 166 } 167 168 RefVal autorelease() const { 169 return RefVal(getKind(), getObjKind(), getCount(), getAutoreleaseCount()+1, 170 getType()); 171 } 172 173 void Profile(llvm::FoldingSetNodeID& ID) const { 174 ID.AddInteger((unsigned) kind); 175 ID.AddInteger(Cnt); 176 ID.AddInteger(ACnt); 177 ID.Add(T); 178 } 179 180 void print(raw_ostream &Out) const; 181}; 182 183void RefVal::print(raw_ostream &Out) const { 184 if (!T.isNull()) 185 Out << "Tracked " << T.getAsString() << '/'; 186 187 switch (getKind()) { 188 default: llvm_unreachable("Invalid RefVal kind"); 189 case Owned: { 190 Out << "Owned"; 191 unsigned cnt = getCount(); 192 if (cnt) Out << " (+ " << cnt << ")"; 193 break; 194 } 195 196 case NotOwned: { 197 Out << "NotOwned"; 198 unsigned cnt = getCount(); 199 if (cnt) Out << " (+ " << cnt << ")"; 200 break; 201 } 202 203 case ReturnedOwned: { 204 Out << "ReturnedOwned"; 205 unsigned cnt = getCount(); 206 if (cnt) Out << " (+ " << cnt << ")"; 207 break; 208 } 209 210 case ReturnedNotOwned: { 211 Out << "ReturnedNotOwned"; 212 unsigned cnt = getCount(); 213 if (cnt) Out << " (+ " << cnt << ")"; 214 break; 215 } 216 217 case Released: 218 Out << "Released"; 219 break; 220 221 case ErrorDeallocGC: 222 Out << "-dealloc (GC)"; 223 break; 224 225 case ErrorDeallocNotOwned: 226 Out << "-dealloc (not-owned)"; 227 break; 228 229 case ErrorLeak: 230 Out << "Leaked"; 231 break; 232 233 case ErrorLeakReturned: 234 Out << "Leaked (Bad naming)"; 235 break; 236 237 case ErrorGCLeakReturned: 238 Out << "Leaked (GC-ed at return)"; 239 break; 240 241 case ErrorUseAfterRelease: 242 Out << "Use-After-Release [ERROR]"; 243 break; 244 245 case ErrorReleaseNotOwned: 246 Out << "Release of Not-Owned [ERROR]"; 247 break; 248 249 case RefVal::ErrorOverAutorelease: 250 Out << "Over-autoreleased"; 251 break; 252 253 case RefVal::ErrorReturnedNotOwned: 254 Out << "Non-owned object returned instead of owned"; 255 break; 256 } 257 258 if (ACnt) { 259 Out << " [ARC +" << ACnt << ']'; 260 } 261} 262} //end anonymous namespace 263 264//===----------------------------------------------------------------------===// 265// RefBindings - State used to track object reference counts. 266//===----------------------------------------------------------------------===// 267 268REGISTER_MAP_WITH_PROGRAMSTATE(RefBindings, SymbolRef, RefVal) 269 270static inline const RefVal *getRefBinding(ProgramStateRef State, 271 SymbolRef Sym) { 272 return State->get<RefBindings>(Sym); 273} 274 275static inline ProgramStateRef setRefBinding(ProgramStateRef State, 276 SymbolRef Sym, RefVal Val) { 277 return State->set<RefBindings>(Sym, Val); 278} 279 280static ProgramStateRef removeRefBinding(ProgramStateRef State, SymbolRef Sym) { 281 return State->remove<RefBindings>(Sym); 282} 283 284//===----------------------------------------------------------------------===// 285// Function/Method behavior summaries. 286//===----------------------------------------------------------------------===// 287 288namespace { 289class RetainSummary { 290 /// Args - a map of (index, ArgEffect) pairs, where index 291 /// specifies the argument (starting from 0). This can be sparsely 292 /// populated; arguments with no entry in Args use 'DefaultArgEffect'. 293 ArgEffects Args; 294 295 /// DefaultArgEffect - The default ArgEffect to apply to arguments that 296 /// do not have an entry in Args. 297 ArgEffect DefaultArgEffect; 298 299 /// Receiver - If this summary applies to an Objective-C message expression, 300 /// this is the effect applied to the state of the receiver. 301 ArgEffect Receiver; 302 303 /// Ret - The effect on the return value. Used to indicate if the 304 /// function/method call returns a new tracked symbol. 305 RetEffect Ret; 306 307public: 308 RetainSummary(ArgEffects A, RetEffect R, ArgEffect defaultEff, 309 ArgEffect ReceiverEff) 310 : Args(A), DefaultArgEffect(defaultEff), Receiver(ReceiverEff), Ret(R) {} 311 312 /// getArg - Return the argument effect on the argument specified by 313 /// idx (starting from 0). 314 ArgEffect getArg(unsigned idx) const { 315 if (const ArgEffect *AE = Args.lookup(idx)) 316 return *AE; 317 318 return DefaultArgEffect; 319 } 320 321 void addArg(ArgEffects::Factory &af, unsigned idx, ArgEffect e) { 322 Args = af.add(Args, idx, e); 323 } 324 325 /// setDefaultArgEffect - Set the default argument effect. 326 void setDefaultArgEffect(ArgEffect E) { 327 DefaultArgEffect = E; 328 } 329 330 /// getRetEffect - Returns the effect on the return value of the call. 331 RetEffect getRetEffect() const { return Ret; } 332 333 /// setRetEffect - Set the effect of the return value of the call. 334 void setRetEffect(RetEffect E) { Ret = E; } 335 336 337 /// Sets the effect on the receiver of the message. 338 void setReceiverEffect(ArgEffect e) { Receiver = e; } 339 340 /// getReceiverEffect - Returns the effect on the receiver of the call. 341 /// This is only meaningful if the summary applies to an ObjCMessageExpr*. 342 ArgEffect getReceiverEffect() const { return Receiver; } 343 344 /// Test if two retain summaries are identical. Note that merely equivalent 345 /// summaries are not necessarily identical (for example, if an explicit 346 /// argument effect matches the default effect). 347 bool operator==(const RetainSummary &Other) const { 348 return Args == Other.Args && DefaultArgEffect == Other.DefaultArgEffect && 349 Receiver == Other.Receiver && Ret == Other.Ret; 350 } 351 352 /// Profile this summary for inclusion in a FoldingSet. 353 void Profile(llvm::FoldingSetNodeID& ID) const { 354 ID.Add(Args); 355 ID.Add(DefaultArgEffect); 356 ID.Add(Receiver); 357 ID.Add(Ret); 358 } 359 360 /// A retain summary is simple if it has no ArgEffects other than the default. 361 bool isSimple() const { 362 return Args.isEmpty(); 363 } 364 365private: 366 ArgEffects getArgEffects() const { return Args; } 367 ArgEffect getDefaultArgEffect() const { return DefaultArgEffect; } 368 369 friend class RetainSummaryManager; 370}; 371} // end anonymous namespace 372 373//===----------------------------------------------------------------------===// 374// Data structures for constructing summaries. 375//===----------------------------------------------------------------------===// 376 377namespace { 378class ObjCSummaryKey { 379 IdentifierInfo* II; 380 Selector S; 381public: 382 ObjCSummaryKey(IdentifierInfo* ii, Selector s) 383 : II(ii), S(s) {} 384 385 ObjCSummaryKey(const ObjCInterfaceDecl *d, Selector s) 386 : II(d ? d->getIdentifier() : 0), S(s) {} 387 388 ObjCSummaryKey(Selector s) 389 : II(0), S(s) {} 390 391 IdentifierInfo *getIdentifier() const { return II; } 392 Selector getSelector() const { return S; } 393}; 394} 395 396namespace llvm { 397template <> struct DenseMapInfo<ObjCSummaryKey> { 398 static inline ObjCSummaryKey getEmptyKey() { 399 return ObjCSummaryKey(DenseMapInfo<IdentifierInfo*>::getEmptyKey(), 400 DenseMapInfo<Selector>::getEmptyKey()); 401 } 402 403 static inline ObjCSummaryKey getTombstoneKey() { 404 return ObjCSummaryKey(DenseMapInfo<IdentifierInfo*>::getTombstoneKey(), 405 DenseMapInfo<Selector>::getTombstoneKey()); 406 } 407 408 static unsigned getHashValue(const ObjCSummaryKey &V) { 409 typedef std::pair<IdentifierInfo*, Selector> PairTy; 410 return DenseMapInfo<PairTy>::getHashValue(PairTy(V.getIdentifier(), 411 V.getSelector())); 412 } 413 414 static bool isEqual(const ObjCSummaryKey& LHS, const ObjCSummaryKey& RHS) { 415 return LHS.getIdentifier() == RHS.getIdentifier() && 416 LHS.getSelector() == RHS.getSelector(); 417 } 418 419}; 420} // end llvm namespace 421 422namespace { 423class ObjCSummaryCache { 424 typedef llvm::DenseMap<ObjCSummaryKey, const RetainSummary *> MapTy; 425 MapTy M; 426public: 427 ObjCSummaryCache() {} 428 429 const RetainSummary * find(const ObjCInterfaceDecl *D, Selector S) { 430 // Do a lookup with the (D,S) pair. If we find a match return 431 // the iterator. 432 ObjCSummaryKey K(D, S); 433 MapTy::iterator I = M.find(K); 434 435 if (I != M.end()) 436 return I->second; 437 if (!D) 438 return NULL; 439 440 // Walk the super chain. If we find a hit with a parent, we'll end 441 // up returning that summary. We actually allow that key (null,S), as 442 // we cache summaries for the null ObjCInterfaceDecl* to allow us to 443 // generate initial summaries without having to worry about NSObject 444 // being declared. 445 // FIXME: We may change this at some point. 446 for (ObjCInterfaceDecl *C=D->getSuperClass() ;; C=C->getSuperClass()) { 447 if ((I = M.find(ObjCSummaryKey(C, S))) != M.end()) 448 break; 449 450 if (!C) 451 return NULL; 452 } 453 454 // Cache the summary with original key to make the next lookup faster 455 // and return the iterator. 456 const RetainSummary *Summ = I->second; 457 M[K] = Summ; 458 return Summ; 459 } 460 461 const RetainSummary *find(IdentifierInfo* II, Selector S) { 462 // FIXME: Class method lookup. Right now we dont' have a good way 463 // of going between IdentifierInfo* and the class hierarchy. 464 MapTy::iterator I = M.find(ObjCSummaryKey(II, S)); 465 466 if (I == M.end()) 467 I = M.find(ObjCSummaryKey(S)); 468 469 return I == M.end() ? NULL : I->second; 470 } 471 472 const RetainSummary *& operator[](ObjCSummaryKey K) { 473 return M[K]; 474 } 475 476 const RetainSummary *& operator[](Selector S) { 477 return M[ ObjCSummaryKey(S) ]; 478 } 479}; 480} // end anonymous namespace 481 482//===----------------------------------------------------------------------===// 483// Data structures for managing collections of summaries. 484//===----------------------------------------------------------------------===// 485 486namespace { 487class RetainSummaryManager { 488 489 //==-----------------------------------------------------------------==// 490 // Typedefs. 491 //==-----------------------------------------------------------------==// 492 493 typedef llvm::DenseMap<const FunctionDecl*, const RetainSummary *> 494 FuncSummariesTy; 495 496 typedef ObjCSummaryCache ObjCMethodSummariesTy; 497 498 typedef llvm::FoldingSetNodeWrapper<RetainSummary> CachedSummaryNode; 499 500 //==-----------------------------------------------------------------==// 501 // Data. 502 //==-----------------------------------------------------------------==// 503 504 /// Ctx - The ASTContext object for the analyzed ASTs. 505 ASTContext &Ctx; 506 507 /// GCEnabled - Records whether or not the analyzed code runs in GC mode. 508 const bool GCEnabled; 509 510 /// Records whether or not the analyzed code runs in ARC mode. 511 const bool ARCEnabled; 512 513 /// FuncSummaries - A map from FunctionDecls to summaries. 514 FuncSummariesTy FuncSummaries; 515 516 /// ObjCClassMethodSummaries - A map from selectors (for instance methods) 517 /// to summaries. 518 ObjCMethodSummariesTy ObjCClassMethodSummaries; 519 520 /// ObjCMethodSummaries - A map from selectors to summaries. 521 ObjCMethodSummariesTy ObjCMethodSummaries; 522 523 /// BPAlloc - A BumpPtrAllocator used for allocating summaries, ArgEffects, 524 /// and all other data used by the checker. 525 llvm::BumpPtrAllocator BPAlloc; 526 527 /// AF - A factory for ArgEffects objects. 528 ArgEffects::Factory AF; 529 530 /// ScratchArgs - A holding buffer for construct ArgEffects. 531 ArgEffects ScratchArgs; 532 533 /// ObjCAllocRetE - Default return effect for methods returning Objective-C 534 /// objects. 535 RetEffect ObjCAllocRetE; 536 537 /// ObjCInitRetE - Default return effect for init methods returning 538 /// Objective-C objects. 539 RetEffect ObjCInitRetE; 540 541 /// SimpleSummaries - Used for uniquing summaries that don't have special 542 /// effects. 543 llvm::FoldingSet<CachedSummaryNode> SimpleSummaries; 544 545 //==-----------------------------------------------------------------==// 546 // Methods. 547 //==-----------------------------------------------------------------==// 548 549 /// getArgEffects - Returns a persistent ArgEffects object based on the 550 /// data in ScratchArgs. 551 ArgEffects getArgEffects(); 552 553 enum UnaryFuncKind { cfretain, cfrelease, cfmakecollectable }; 554 555 const RetainSummary *getUnarySummary(const FunctionType* FT, 556 UnaryFuncKind func); 557 558 const RetainSummary *getCFSummaryCreateRule(const FunctionDecl *FD); 559 const RetainSummary *getCFSummaryGetRule(const FunctionDecl *FD); 560 const RetainSummary *getCFCreateGetRuleSummary(const FunctionDecl *FD); 561 562 const RetainSummary *getPersistentSummary(const RetainSummary &OldSumm); 563 564 const RetainSummary *getPersistentSummary(RetEffect RetEff, 565 ArgEffect ReceiverEff = DoNothing, 566 ArgEffect DefaultEff = MayEscape) { 567 RetainSummary Summ(getArgEffects(), RetEff, DefaultEff, ReceiverEff); 568 return getPersistentSummary(Summ); 569 } 570 571 const RetainSummary *getDoNothingSummary() { 572 return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 573 } 574 575 const RetainSummary *getDefaultSummary() { 576 return getPersistentSummary(RetEffect::MakeNoRet(), 577 DoNothing, MayEscape); 578 } 579 580 const RetainSummary *getPersistentStopSummary() { 581 return getPersistentSummary(RetEffect::MakeNoRet(), 582 StopTracking, StopTracking); 583 } 584 585 void InitializeClassMethodSummaries(); 586 void InitializeMethodSummaries(); 587private: 588 void addNSObjectClsMethSummary(Selector S, const RetainSummary *Summ) { 589 ObjCClassMethodSummaries[S] = Summ; 590 } 591 592 void addNSObjectMethSummary(Selector S, const RetainSummary *Summ) { 593 ObjCMethodSummaries[S] = Summ; 594 } 595 596 void addClassMethSummary(const char* Cls, const char* name, 597 const RetainSummary *Summ, bool isNullary = true) { 598 IdentifierInfo* ClsII = &Ctx.Idents.get(Cls); 599 Selector S = isNullary ? GetNullarySelector(name, Ctx) 600 : GetUnarySelector(name, Ctx); 601 ObjCClassMethodSummaries[ObjCSummaryKey(ClsII, S)] = Summ; 602 } 603 604 void addInstMethSummary(const char* Cls, const char* nullaryName, 605 const RetainSummary *Summ) { 606 IdentifierInfo* ClsII = &Ctx.Idents.get(Cls); 607 Selector S = GetNullarySelector(nullaryName, Ctx); 608 ObjCMethodSummaries[ObjCSummaryKey(ClsII, S)] = Summ; 609 } 610 611 Selector generateSelector(va_list argp) { 612 SmallVector<IdentifierInfo*, 10> II; 613 614 while (const char* s = va_arg(argp, const char*)) 615 II.push_back(&Ctx.Idents.get(s)); 616 617 return Ctx.Selectors.getSelector(II.size(), &II[0]); 618 } 619 620 void addMethodSummary(IdentifierInfo *ClsII, ObjCMethodSummariesTy& Summaries, 621 const RetainSummary * Summ, va_list argp) { 622 Selector S = generateSelector(argp); 623 Summaries[ObjCSummaryKey(ClsII, S)] = Summ; 624 } 625 626 void addInstMethSummary(const char* Cls, const RetainSummary * Summ, ...) { 627 va_list argp; 628 va_start(argp, Summ); 629 addMethodSummary(&Ctx.Idents.get(Cls), ObjCMethodSummaries, Summ, argp); 630 va_end(argp); 631 } 632 633 void addClsMethSummary(const char* Cls, const RetainSummary * Summ, ...) { 634 va_list argp; 635 va_start(argp, Summ); 636 addMethodSummary(&Ctx.Idents.get(Cls),ObjCClassMethodSummaries, Summ, argp); 637 va_end(argp); 638 } 639 640 void addClsMethSummary(IdentifierInfo *II, const RetainSummary * Summ, ...) { 641 va_list argp; 642 va_start(argp, Summ); 643 addMethodSummary(II, ObjCClassMethodSummaries, Summ, argp); 644 va_end(argp); 645 } 646 647public: 648 649 RetainSummaryManager(ASTContext &ctx, bool gcenabled, bool usesARC) 650 : Ctx(ctx), 651 GCEnabled(gcenabled), 652 ARCEnabled(usesARC), 653 AF(BPAlloc), ScratchArgs(AF.getEmptyMap()), 654 ObjCAllocRetE(gcenabled 655 ? RetEffect::MakeGCNotOwned() 656 : (usesARC ? RetEffect::MakeARCNotOwned() 657 : RetEffect::MakeOwned(RetEffect::ObjC, true))), 658 ObjCInitRetE(gcenabled 659 ? RetEffect::MakeGCNotOwned() 660 : (usesARC ? RetEffect::MakeARCNotOwned() 661 : RetEffect::MakeOwnedWhenTrackedReceiver())) { 662 InitializeClassMethodSummaries(); 663 InitializeMethodSummaries(); 664 } 665 666 const RetainSummary *getSummary(const CallEvent &Call, 667 ProgramStateRef State = 0); 668 669 const RetainSummary *getFunctionSummary(const FunctionDecl *FD); 670 671 const RetainSummary *getMethodSummary(Selector S, const ObjCInterfaceDecl *ID, 672 const ObjCMethodDecl *MD, 673 QualType RetTy, 674 ObjCMethodSummariesTy &CachedSummaries); 675 676 const RetainSummary *getInstanceMethodSummary(const ObjCMethodCall &M, 677 ProgramStateRef State); 678 679 const RetainSummary *getClassMethodSummary(const ObjCMethodCall &M) { 680 assert(!M.isInstanceMessage()); 681 const ObjCInterfaceDecl *Class = M.getReceiverInterface(); 682 683 return getMethodSummary(M.getSelector(), Class, M.getDecl(), 684 M.getResultType(), ObjCClassMethodSummaries); 685 } 686 687 /// getMethodSummary - This version of getMethodSummary is used to query 688 /// the summary for the current method being analyzed. 689 const RetainSummary *getMethodSummary(const ObjCMethodDecl *MD) { 690 const ObjCInterfaceDecl *ID = MD->getClassInterface(); 691 Selector S = MD->getSelector(); 692 QualType ResultTy = MD->getResultType(); 693 694 ObjCMethodSummariesTy *CachedSummaries; 695 if (MD->isInstanceMethod()) 696 CachedSummaries = &ObjCMethodSummaries; 697 else 698 CachedSummaries = &ObjCClassMethodSummaries; 699 700 return getMethodSummary(S, ID, MD, ResultTy, *CachedSummaries); 701 } 702 703 const RetainSummary *getStandardMethodSummary(const ObjCMethodDecl *MD, 704 Selector S, QualType RetTy); 705 706 /// Determine if there is a special return effect for this function or method. 707 Optional<RetEffect> getRetEffectFromAnnotations(QualType RetTy, 708 const Decl *D); 709 710 void updateSummaryFromAnnotations(const RetainSummary *&Summ, 711 const ObjCMethodDecl *MD); 712 713 void updateSummaryFromAnnotations(const RetainSummary *&Summ, 714 const FunctionDecl *FD); 715 716 void updateSummaryForCall(const RetainSummary *&Summ, 717 const CallEvent &Call); 718 719 bool isGCEnabled() const { return GCEnabled; } 720 721 bool isARCEnabled() const { return ARCEnabled; } 722 723 bool isARCorGCEnabled() const { return GCEnabled || ARCEnabled; } 724 725 RetEffect getObjAllocRetEffect() const { return ObjCAllocRetE; } 726 727 friend class RetainSummaryTemplate; 728}; 729 730// Used to avoid allocating long-term (BPAlloc'd) memory for default retain 731// summaries. If a function or method looks like it has a default summary, but 732// it has annotations, the annotations are added to the stack-based template 733// and then copied into managed memory. 734class RetainSummaryTemplate { 735 RetainSummaryManager &Manager; 736 const RetainSummary *&RealSummary; 737 RetainSummary ScratchSummary; 738 bool Accessed; 739public: 740 RetainSummaryTemplate(const RetainSummary *&real, RetainSummaryManager &mgr) 741 : Manager(mgr), RealSummary(real), ScratchSummary(*real), Accessed(false) {} 742 743 ~RetainSummaryTemplate() { 744 if (Accessed) 745 RealSummary = Manager.getPersistentSummary(ScratchSummary); 746 } 747 748 RetainSummary &operator*() { 749 Accessed = true; 750 return ScratchSummary; 751 } 752 753 RetainSummary *operator->() { 754 Accessed = true; 755 return &ScratchSummary; 756 } 757}; 758 759} // end anonymous namespace 760 761//===----------------------------------------------------------------------===// 762// Implementation of checker data structures. 763//===----------------------------------------------------------------------===// 764 765ArgEffects RetainSummaryManager::getArgEffects() { 766 ArgEffects AE = ScratchArgs; 767 ScratchArgs = AF.getEmptyMap(); 768 return AE; 769} 770 771const RetainSummary * 772RetainSummaryManager::getPersistentSummary(const RetainSummary &OldSumm) { 773 // Unique "simple" summaries -- those without ArgEffects. 774 if (OldSumm.isSimple()) { 775 llvm::FoldingSetNodeID ID; 776 OldSumm.Profile(ID); 777 778 void *Pos; 779 CachedSummaryNode *N = SimpleSummaries.FindNodeOrInsertPos(ID, Pos); 780 781 if (!N) { 782 N = (CachedSummaryNode *) BPAlloc.Allocate<CachedSummaryNode>(); 783 new (N) CachedSummaryNode(OldSumm); 784 SimpleSummaries.InsertNode(N, Pos); 785 } 786 787 return &N->getValue(); 788 } 789 790 RetainSummary *Summ = (RetainSummary *) BPAlloc.Allocate<RetainSummary>(); 791 new (Summ) RetainSummary(OldSumm); 792 return Summ; 793} 794 795//===----------------------------------------------------------------------===// 796// Summary creation for functions (largely uses of Core Foundation). 797//===----------------------------------------------------------------------===// 798 799static bool isRetain(const FunctionDecl *FD, StringRef FName) { 800 return FName.endswith("Retain"); 801} 802 803static bool isRelease(const FunctionDecl *FD, StringRef FName) { 804 return FName.endswith("Release"); 805} 806 807static bool isMakeCollectable(const FunctionDecl *FD, StringRef FName) { 808 // FIXME: Remove FunctionDecl parameter. 809 // FIXME: Is it really okay if MakeCollectable isn't a suffix? 810 return FName.find("MakeCollectable") != StringRef::npos; 811} 812 813static ArgEffect getStopTrackingHardEquivalent(ArgEffect E) { 814 switch (E) { 815 case DoNothing: 816 case Autorelease: 817 case DecRefBridgedTransfered: 818 case IncRef: 819 case IncRefMsg: 820 case MakeCollectable: 821 case MayEscape: 822 case StopTracking: 823 case StopTrackingHard: 824 return StopTrackingHard; 825 case DecRef: 826 case DecRefAndStopTrackingHard: 827 return DecRefAndStopTrackingHard; 828 case DecRefMsg: 829 case DecRefMsgAndStopTrackingHard: 830 return DecRefMsgAndStopTrackingHard; 831 case Dealloc: 832 return Dealloc; 833 } 834 835 llvm_unreachable("Unknown ArgEffect kind"); 836} 837 838void RetainSummaryManager::updateSummaryForCall(const RetainSummary *&S, 839 const CallEvent &Call) { 840 if (Call.hasNonZeroCallbackArg()) { 841 ArgEffect RecEffect = 842 getStopTrackingHardEquivalent(S->getReceiverEffect()); 843 ArgEffect DefEffect = 844 getStopTrackingHardEquivalent(S->getDefaultArgEffect()); 845 846 ArgEffects CustomArgEffects = S->getArgEffects(); 847 for (ArgEffects::iterator I = CustomArgEffects.begin(), 848 E = CustomArgEffects.end(); 849 I != E; ++I) { 850 ArgEffect Translated = getStopTrackingHardEquivalent(I->second); 851 if (Translated != DefEffect) 852 ScratchArgs = AF.add(ScratchArgs, I->first, Translated); 853 } 854 855 RetEffect RE = RetEffect::MakeNoRetHard(); 856 857 // Special cases where the callback argument CANNOT free the return value. 858 // This can generally only happen if we know that the callback will only be 859 // called when the return value is already being deallocated. 860 if (const FunctionCall *FC = dyn_cast<FunctionCall>(&Call)) { 861 if (IdentifierInfo *Name = FC->getDecl()->getIdentifier()) { 862 // When the CGBitmapContext is deallocated, the callback here will free 863 // the associated data buffer. 864 if (Name->isStr("CGBitmapContextCreateWithData")) 865 RE = S->getRetEffect(); 866 } 867 } 868 869 S = getPersistentSummary(RE, RecEffect, DefEffect); 870 } 871 872 // Special case '[super init];' and '[self init];' 873 // 874 // Even though calling '[super init]' without assigning the result to self 875 // and checking if the parent returns 'nil' is a bad pattern, it is common. 876 // Additionally, our Self Init checker already warns about it. To avoid 877 // overwhelming the user with messages from both checkers, we model the case 878 // of '[super init]' in cases when it is not consumed by another expression 879 // as if the call preserves the value of 'self'; essentially, assuming it can 880 // never fail and return 'nil'. 881 // Note, we don't want to just stop tracking the value since we want the 882 // RetainCount checker to report leaks and use-after-free if SelfInit checker 883 // is turned off. 884 if (const ObjCMethodCall *MC = dyn_cast<ObjCMethodCall>(&Call)) { 885 if (MC->getMethodFamily() == OMF_init && MC->isReceiverSelfOrSuper()) { 886 887 // Check if the message is not consumed, we know it will not be used in 888 // an assignment, ex: "self = [super init]". 889 const Expr *ME = MC->getOriginExpr(); 890 const LocationContext *LCtx = MC->getLocationContext(); 891 ParentMap &PM = LCtx->getAnalysisDeclContext()->getParentMap(); 892 if (!PM.isConsumedExpr(ME)) { 893 RetainSummaryTemplate ModifiableSummaryTemplate(S, *this); 894 ModifiableSummaryTemplate->setReceiverEffect(DoNothing); 895 ModifiableSummaryTemplate->setRetEffect(RetEffect::MakeNoRet()); 896 } 897 } 898 899 } 900} 901 902const RetainSummary * 903RetainSummaryManager::getSummary(const CallEvent &Call, 904 ProgramStateRef State) { 905 const RetainSummary *Summ; 906 switch (Call.getKind()) { 907 case CE_Function: 908 Summ = getFunctionSummary(cast<FunctionCall>(Call).getDecl()); 909 break; 910 case CE_CXXMember: 911 case CE_CXXMemberOperator: 912 case CE_Block: 913 case CE_CXXConstructor: 914 case CE_CXXDestructor: 915 case CE_CXXAllocator: 916 // FIXME: These calls are currently unsupported. 917 return getPersistentStopSummary(); 918 case CE_ObjCMessage: { 919 const ObjCMethodCall &Msg = cast<ObjCMethodCall>(Call); 920 if (Msg.isInstanceMessage()) 921 Summ = getInstanceMethodSummary(Msg, State); 922 else 923 Summ = getClassMethodSummary(Msg); 924 break; 925 } 926 } 927 928 updateSummaryForCall(Summ, Call); 929 930 assert(Summ && "Unknown call type?"); 931 return Summ; 932} 933 934const RetainSummary * 935RetainSummaryManager::getFunctionSummary(const FunctionDecl *FD) { 936 // If we don't know what function we're calling, use our default summary. 937 if (!FD) 938 return getDefaultSummary(); 939 940 // Look up a summary in our cache of FunctionDecls -> Summaries. 941 FuncSummariesTy::iterator I = FuncSummaries.find(FD); 942 if (I != FuncSummaries.end()) 943 return I->second; 944 945 // No summary? Generate one. 946 const RetainSummary *S = 0; 947 bool AllowAnnotations = true; 948 949 do { 950 // We generate "stop" summaries for implicitly defined functions. 951 if (FD->isImplicit()) { 952 S = getPersistentStopSummary(); 953 break; 954 } 955 956 // [PR 3337] Use 'getAs<FunctionType>' to strip away any typedefs on the 957 // function's type. 958 const FunctionType* FT = FD->getType()->getAs<FunctionType>(); 959 const IdentifierInfo *II = FD->getIdentifier(); 960 if (!II) 961 break; 962 963 StringRef FName = II->getName(); 964 965 // Strip away preceding '_'. Doing this here will effect all the checks 966 // down below. 967 FName = FName.substr(FName.find_first_not_of('_')); 968 969 // Inspect the result type. 970 QualType RetTy = FT->getResultType(); 971 972 // FIXME: This should all be refactored into a chain of "summary lookup" 973 // filters. 974 assert(ScratchArgs.isEmpty()); 975 976 if (FName == "pthread_create" || FName == "pthread_setspecific") { 977 // Part of: <rdar://problem/7299394> and <rdar://problem/11282706>. 978 // This will be addressed better with IPA. 979 S = getPersistentStopSummary(); 980 } else if (FName == "NSMakeCollectable") { 981 // Handle: id NSMakeCollectable(CFTypeRef) 982 S = (RetTy->isObjCIdType()) 983 ? getUnarySummary(FT, cfmakecollectable) 984 : getPersistentStopSummary(); 985 // The headers on OS X 10.8 use cf_consumed/ns_returns_retained, 986 // but we can fully model NSMakeCollectable ourselves. 987 AllowAnnotations = false; 988 } else if (FName == "CFPlugInInstanceCreate") { 989 S = getPersistentSummary(RetEffect::MakeNoRet()); 990 } else if (FName == "IOBSDNameMatching" || 991 FName == "IOServiceMatching" || 992 FName == "IOServiceNameMatching" || 993 FName == "IORegistryEntrySearchCFProperty" || 994 FName == "IORegistryEntryIDMatching" || 995 FName == "IOOpenFirmwarePathMatching") { 996 // Part of <rdar://problem/6961230>. (IOKit) 997 // This should be addressed using a API table. 998 S = getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true), 999 DoNothing, DoNothing); 1000 } else if (FName == "IOServiceGetMatchingService" || 1001 FName == "IOServiceGetMatchingServices") { 1002 // FIXES: <rdar://problem/6326900> 1003 // This should be addressed using a API table. This strcmp is also 1004 // a little gross, but there is no need to super optimize here. 1005 ScratchArgs = AF.add(ScratchArgs, 1, DecRef); 1006 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 1007 } else if (FName == "IOServiceAddNotification" || 1008 FName == "IOServiceAddMatchingNotification") { 1009 // Part of <rdar://problem/6961230>. (IOKit) 1010 // This should be addressed using a API table. 1011 ScratchArgs = AF.add(ScratchArgs, 2, DecRef); 1012 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 1013 } else if (FName == "CVPixelBufferCreateWithBytes") { 1014 // FIXES: <rdar://problem/7283567> 1015 // Eventually this can be improved by recognizing that the pixel 1016 // buffer passed to CVPixelBufferCreateWithBytes is released via 1017 // a callback and doing full IPA to make sure this is done correctly. 1018 // FIXME: This function has an out parameter that returns an 1019 // allocated object. 1020 ScratchArgs = AF.add(ScratchArgs, 7, StopTracking); 1021 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 1022 } else if (FName == "CGBitmapContextCreateWithData") { 1023 // FIXES: <rdar://problem/7358899> 1024 // Eventually this can be improved by recognizing that 'releaseInfo' 1025 // passed to CGBitmapContextCreateWithData is released via 1026 // a callback and doing full IPA to make sure this is done correctly. 1027 ScratchArgs = AF.add(ScratchArgs, 8, StopTracking); 1028 S = getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true), 1029 DoNothing, DoNothing); 1030 } else if (FName == "CVPixelBufferCreateWithPlanarBytes") { 1031 // FIXES: <rdar://problem/7283567> 1032 // Eventually this can be improved by recognizing that the pixel 1033 // buffer passed to CVPixelBufferCreateWithPlanarBytes is released 1034 // via a callback and doing full IPA to make sure this is done 1035 // correctly. 1036 ScratchArgs = AF.add(ScratchArgs, 12, StopTracking); 1037 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 1038 } else if (FName == "dispatch_set_context" || 1039 FName == "xpc_connection_set_context") { 1040 // <rdar://problem/11059275> - The analyzer currently doesn't have 1041 // a good way to reason about the finalizer function for libdispatch. 1042 // If we pass a context object that is memory managed, stop tracking it. 1043 // <rdar://problem/13783514> - Same problem, but for XPC. 1044 // FIXME: this hack should possibly go away once we can handle 1045 // libdispatch and XPC finalizers. 1046 ScratchArgs = AF.add(ScratchArgs, 1, StopTracking); 1047 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 1048 } else if (FName.startswith("NSLog")) { 1049 S = getDoNothingSummary(); 1050 } else if (FName.startswith("NS") && 1051 (FName.find("Insert") != StringRef::npos)) { 1052 // Whitelist NSXXInsertXX, for example NSMapInsertIfAbsent, since they can 1053 // be deallocated by NSMapRemove. (radar://11152419) 1054 ScratchArgs = AF.add(ScratchArgs, 1, StopTracking); 1055 ScratchArgs = AF.add(ScratchArgs, 2, StopTracking); 1056 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 1057 } 1058 1059 // Did we get a summary? 1060 if (S) 1061 break; 1062 1063 if (RetTy->isPointerType()) { 1064 // For CoreFoundation ('CF') types. 1065 if (cocoa::isRefType(RetTy, "CF", FName)) { 1066 if (isRetain(FD, FName)) 1067 S = getUnarySummary(FT, cfretain); 1068 else if (isMakeCollectable(FD, FName)) 1069 S = getUnarySummary(FT, cfmakecollectable); 1070 else 1071 S = getCFCreateGetRuleSummary(FD); 1072 1073 break; 1074 } 1075 1076 // For CoreGraphics ('CG') types. 1077 if (cocoa::isRefType(RetTy, "CG", FName)) { 1078 if (isRetain(FD, FName)) 1079 S = getUnarySummary(FT, cfretain); 1080 else 1081 S = getCFCreateGetRuleSummary(FD); 1082 1083 break; 1084 } 1085 1086 // For the Disk Arbitration API (DiskArbitration/DADisk.h) 1087 if (cocoa::isRefType(RetTy, "DADisk") || 1088 cocoa::isRefType(RetTy, "DADissenter") || 1089 cocoa::isRefType(RetTy, "DASessionRef")) { 1090 S = getCFCreateGetRuleSummary(FD); 1091 break; 1092 } 1093 1094 if (FD->getAttr<CFAuditedTransferAttr>()) { 1095 S = getCFCreateGetRuleSummary(FD); 1096 break; 1097 } 1098 1099 break; 1100 } 1101 1102 // Check for release functions, the only kind of functions that we care 1103 // about that don't return a pointer type. 1104 if (FName[0] == 'C' && (FName[1] == 'F' || FName[1] == 'G')) { 1105 // Test for 'CGCF'. 1106 FName = FName.substr(FName.startswith("CGCF") ? 4 : 2); 1107 1108 if (isRelease(FD, FName)) 1109 S = getUnarySummary(FT, cfrelease); 1110 else { 1111 assert (ScratchArgs.isEmpty()); 1112 // Remaining CoreFoundation and CoreGraphics functions. 1113 // We use to assume that they all strictly followed the ownership idiom 1114 // and that ownership cannot be transferred. While this is technically 1115 // correct, many methods allow a tracked object to escape. For example: 1116 // 1117 // CFMutableDictionaryRef x = CFDictionaryCreateMutable(...); 1118 // CFDictionaryAddValue(y, key, x); 1119 // CFRelease(x); 1120 // ... it is okay to use 'x' since 'y' has a reference to it 1121 // 1122 // We handle this and similar cases with the follow heuristic. If the 1123 // function name contains "InsertValue", "SetValue", "AddValue", 1124 // "AppendValue", or "SetAttribute", then we assume that arguments may 1125 // "escape." This means that something else holds on to the object, 1126 // allowing it be used even after its local retain count drops to 0. 1127 ArgEffect E = (StrInStrNoCase(FName, "InsertValue") != StringRef::npos|| 1128 StrInStrNoCase(FName, "AddValue") != StringRef::npos || 1129 StrInStrNoCase(FName, "SetValue") != StringRef::npos || 1130 StrInStrNoCase(FName, "AppendValue") != StringRef::npos|| 1131 StrInStrNoCase(FName, "SetAttribute") != StringRef::npos) 1132 ? MayEscape : DoNothing; 1133 1134 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, E); 1135 } 1136 } 1137 } 1138 while (0); 1139 1140 // If we got all the way here without any luck, use a default summary. 1141 if (!S) 1142 S = getDefaultSummary(); 1143 1144 // Annotations override defaults. 1145 if (AllowAnnotations) 1146 updateSummaryFromAnnotations(S, FD); 1147 1148 FuncSummaries[FD] = S; 1149 return S; 1150} 1151 1152const RetainSummary * 1153RetainSummaryManager::getCFCreateGetRuleSummary(const FunctionDecl *FD) { 1154 if (coreFoundation::followsCreateRule(FD)) 1155 return getCFSummaryCreateRule(FD); 1156 1157 return getCFSummaryGetRule(FD); 1158} 1159 1160const RetainSummary * 1161RetainSummaryManager::getUnarySummary(const FunctionType* FT, 1162 UnaryFuncKind func) { 1163 1164 // Sanity check that this is *really* a unary function. This can 1165 // happen if people do weird things. 1166 const FunctionProtoType* FTP = dyn_cast<FunctionProtoType>(FT); 1167 if (!FTP || FTP->getNumArgs() != 1) 1168 return getPersistentStopSummary(); 1169 1170 assert (ScratchArgs.isEmpty()); 1171 1172 ArgEffect Effect; 1173 switch (func) { 1174 case cfretain: Effect = IncRef; break; 1175 case cfrelease: Effect = DecRef; break; 1176 case cfmakecollectable: Effect = MakeCollectable; break; 1177 } 1178 1179 ScratchArgs = AF.add(ScratchArgs, 0, Effect); 1180 return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 1181} 1182 1183const RetainSummary * 1184RetainSummaryManager::getCFSummaryCreateRule(const FunctionDecl *FD) { 1185 assert (ScratchArgs.isEmpty()); 1186 1187 return getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true)); 1188} 1189 1190const RetainSummary * 1191RetainSummaryManager::getCFSummaryGetRule(const FunctionDecl *FD) { 1192 assert (ScratchArgs.isEmpty()); 1193 return getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::CF), 1194 DoNothing, DoNothing); 1195} 1196 1197//===----------------------------------------------------------------------===// 1198// Summary creation for Selectors. 1199//===----------------------------------------------------------------------===// 1200 1201Optional<RetEffect> 1202RetainSummaryManager::getRetEffectFromAnnotations(QualType RetTy, 1203 const Decl *D) { 1204 if (cocoa::isCocoaObjectRef(RetTy)) { 1205 if (D->getAttr<NSReturnsRetainedAttr>()) 1206 return ObjCAllocRetE; 1207 1208 if (D->getAttr<NSReturnsNotRetainedAttr>() || 1209 D->getAttr<NSReturnsAutoreleasedAttr>()) 1210 return RetEffect::MakeNotOwned(RetEffect::ObjC); 1211 1212 } else if (!RetTy->isPointerType()) { 1213 return None; 1214 } 1215 1216 if (D->getAttr<CFReturnsRetainedAttr>()) 1217 return RetEffect::MakeOwned(RetEffect::CF, true); 1218 1219 if (D->getAttr<CFReturnsNotRetainedAttr>()) 1220 return RetEffect::MakeNotOwned(RetEffect::CF); 1221 1222 return None; 1223} 1224 1225void 1226RetainSummaryManager::updateSummaryFromAnnotations(const RetainSummary *&Summ, 1227 const FunctionDecl *FD) { 1228 if (!FD) 1229 return; 1230 1231 assert(Summ && "Must have a summary to add annotations to."); 1232 RetainSummaryTemplate Template(Summ, *this); 1233 1234 // Effects on the parameters. 1235 unsigned parm_idx = 0; 1236 for (FunctionDecl::param_const_iterator pi = FD->param_begin(), 1237 pe = FD->param_end(); pi != pe; ++pi, ++parm_idx) { 1238 const ParmVarDecl *pd = *pi; 1239 if (pd->getAttr<NSConsumedAttr>()) 1240 Template->addArg(AF, parm_idx, DecRefMsg); 1241 else if (pd->getAttr<CFConsumedAttr>()) 1242 Template->addArg(AF, parm_idx, DecRef); 1243 } 1244 1245 QualType RetTy = FD->getResultType(); 1246 if (Optional<RetEffect> RetE = getRetEffectFromAnnotations(RetTy, FD)) 1247 Template->setRetEffect(*RetE); 1248} 1249 1250void 1251RetainSummaryManager::updateSummaryFromAnnotations(const RetainSummary *&Summ, 1252 const ObjCMethodDecl *MD) { 1253 if (!MD) 1254 return; 1255 1256 assert(Summ && "Must have a valid summary to add annotations to"); 1257 RetainSummaryTemplate Template(Summ, *this); 1258 1259 // Effects on the receiver. 1260 if (MD->getAttr<NSConsumesSelfAttr>()) 1261 Template->setReceiverEffect(DecRefMsg); 1262 1263 // Effects on the parameters. 1264 unsigned parm_idx = 0; 1265 for (ObjCMethodDecl::param_const_iterator 1266 pi=MD->param_begin(), pe=MD->param_end(); 1267 pi != pe; ++pi, ++parm_idx) { 1268 const ParmVarDecl *pd = *pi; 1269 if (pd->getAttr<NSConsumedAttr>()) 1270 Template->addArg(AF, parm_idx, DecRefMsg); 1271 else if (pd->getAttr<CFConsumedAttr>()) { 1272 Template->addArg(AF, parm_idx, DecRef); 1273 } 1274 } 1275 1276 QualType RetTy = MD->getResultType(); 1277 if (Optional<RetEffect> RetE = getRetEffectFromAnnotations(RetTy, MD)) 1278 Template->setRetEffect(*RetE); 1279} 1280 1281const RetainSummary * 1282RetainSummaryManager::getStandardMethodSummary(const ObjCMethodDecl *MD, 1283 Selector S, QualType RetTy) { 1284 // Any special effects? 1285 ArgEffect ReceiverEff = DoNothing; 1286 RetEffect ResultEff = RetEffect::MakeNoRet(); 1287 1288 // Check the method family, and apply any default annotations. 1289 switch (MD ? MD->getMethodFamily() : S.getMethodFamily()) { 1290 case OMF_None: 1291 case OMF_performSelector: 1292 // Assume all Objective-C methods follow Cocoa Memory Management rules. 1293 // FIXME: Does the non-threaded performSelector family really belong here? 1294 // The selector could be, say, @selector(copy). 1295 if (cocoa::isCocoaObjectRef(RetTy)) 1296 ResultEff = RetEffect::MakeNotOwned(RetEffect::ObjC); 1297 else if (coreFoundation::isCFObjectRef(RetTy)) { 1298 // ObjCMethodDecl currently doesn't consider CF objects as valid return 1299 // values for alloc, new, copy, or mutableCopy, so we have to 1300 // double-check with the selector. This is ugly, but there aren't that 1301 // many Objective-C methods that return CF objects, right? 1302 if (MD) { 1303 switch (S.getMethodFamily()) { 1304 case OMF_alloc: 1305 case OMF_new: 1306 case OMF_copy: 1307 case OMF_mutableCopy: 1308 ResultEff = RetEffect::MakeOwned(RetEffect::CF, true); 1309 break; 1310 default: 1311 ResultEff = RetEffect::MakeNotOwned(RetEffect::CF); 1312 break; 1313 } 1314 } else { 1315 ResultEff = RetEffect::MakeNotOwned(RetEffect::CF); 1316 } 1317 } 1318 break; 1319 case OMF_init: 1320 ResultEff = ObjCInitRetE; 1321 ReceiverEff = DecRefMsg; 1322 break; 1323 case OMF_alloc: 1324 case OMF_new: 1325 case OMF_copy: 1326 case OMF_mutableCopy: 1327 if (cocoa::isCocoaObjectRef(RetTy)) 1328 ResultEff = ObjCAllocRetE; 1329 else if (coreFoundation::isCFObjectRef(RetTy)) 1330 ResultEff = RetEffect::MakeOwned(RetEffect::CF, true); 1331 break; 1332 case OMF_autorelease: 1333 ReceiverEff = Autorelease; 1334 break; 1335 case OMF_retain: 1336 ReceiverEff = IncRefMsg; 1337 break; 1338 case OMF_release: 1339 ReceiverEff = DecRefMsg; 1340 break; 1341 case OMF_dealloc: 1342 ReceiverEff = Dealloc; 1343 break; 1344 case OMF_self: 1345 // -self is handled specially by the ExprEngine to propagate the receiver. 1346 break; 1347 case OMF_retainCount: 1348 case OMF_finalize: 1349 // These methods don't return objects. 1350 break; 1351 } 1352 1353 // If one of the arguments in the selector has the keyword 'delegate' we 1354 // should stop tracking the reference count for the receiver. This is 1355 // because the reference count is quite possibly handled by a delegate 1356 // method. 1357 if (S.isKeywordSelector()) { 1358 for (unsigned i = 0, e = S.getNumArgs(); i != e; ++i) { 1359 StringRef Slot = S.getNameForSlot(i); 1360 if (Slot.substr(Slot.size() - 8).equals_lower("delegate")) { 1361 if (ResultEff == ObjCInitRetE) 1362 ResultEff = RetEffect::MakeNoRetHard(); 1363 else 1364 ReceiverEff = StopTrackingHard; 1365 } 1366 } 1367 } 1368 1369 if (ScratchArgs.isEmpty() && ReceiverEff == DoNothing && 1370 ResultEff.getKind() == RetEffect::NoRet) 1371 return getDefaultSummary(); 1372 1373 return getPersistentSummary(ResultEff, ReceiverEff, MayEscape); 1374} 1375 1376const RetainSummary * 1377RetainSummaryManager::getInstanceMethodSummary(const ObjCMethodCall &Msg, 1378 ProgramStateRef State) { 1379 const ObjCInterfaceDecl *ReceiverClass = 0; 1380 1381 // We do better tracking of the type of the object than the core ExprEngine. 1382 // See if we have its type in our private state. 1383 // FIXME: Eventually replace the use of state->get<RefBindings> with 1384 // a generic API for reasoning about the Objective-C types of symbolic 1385 // objects. 1386 SVal ReceiverV = Msg.getReceiverSVal(); 1387 if (SymbolRef Sym = ReceiverV.getAsLocSymbol()) 1388 if (const RefVal *T = getRefBinding(State, Sym)) 1389 if (const ObjCObjectPointerType *PT = 1390 T->getType()->getAs<ObjCObjectPointerType>()) 1391 ReceiverClass = PT->getInterfaceDecl(); 1392 1393 // If we don't know what kind of object this is, fall back to its static type. 1394 if (!ReceiverClass) 1395 ReceiverClass = Msg.getReceiverInterface(); 1396 1397 // FIXME: The receiver could be a reference to a class, meaning that 1398 // we should use the class method. 1399 // id x = [NSObject class]; 1400 // [x performSelector:... withObject:... afterDelay:...]; 1401 Selector S = Msg.getSelector(); 1402 const ObjCMethodDecl *Method = Msg.getDecl(); 1403 if (!Method && ReceiverClass) 1404 Method = ReceiverClass->getInstanceMethod(S); 1405 1406 return getMethodSummary(S, ReceiverClass, Method, Msg.getResultType(), 1407 ObjCMethodSummaries); 1408} 1409 1410const RetainSummary * 1411RetainSummaryManager::getMethodSummary(Selector S, const ObjCInterfaceDecl *ID, 1412 const ObjCMethodDecl *MD, QualType RetTy, 1413 ObjCMethodSummariesTy &CachedSummaries) { 1414 1415 // Look up a summary in our summary cache. 1416 const RetainSummary *Summ = CachedSummaries.find(ID, S); 1417 1418 if (!Summ) { 1419 Summ = getStandardMethodSummary(MD, S, RetTy); 1420 1421 // Annotations override defaults. 1422 updateSummaryFromAnnotations(Summ, MD); 1423 1424 // Memoize the summary. 1425 CachedSummaries[ObjCSummaryKey(ID, S)] = Summ; 1426 } 1427 1428 return Summ; 1429} 1430 1431void RetainSummaryManager::InitializeClassMethodSummaries() { 1432 assert(ScratchArgs.isEmpty()); 1433 // Create the [NSAssertionHandler currentHander] summary. 1434 addClassMethSummary("NSAssertionHandler", "currentHandler", 1435 getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::ObjC))); 1436 1437 // Create the [NSAutoreleasePool addObject:] summary. 1438 ScratchArgs = AF.add(ScratchArgs, 0, Autorelease); 1439 addClassMethSummary("NSAutoreleasePool", "addObject", 1440 getPersistentSummary(RetEffect::MakeNoRet(), 1441 DoNothing, Autorelease)); 1442} 1443 1444void RetainSummaryManager::InitializeMethodSummaries() { 1445 1446 assert (ScratchArgs.isEmpty()); 1447 1448 // Create the "init" selector. It just acts as a pass-through for the 1449 // receiver. 1450 const RetainSummary *InitSumm = getPersistentSummary(ObjCInitRetE, DecRefMsg); 1451 addNSObjectMethSummary(GetNullarySelector("init", Ctx), InitSumm); 1452 1453 // awakeAfterUsingCoder: behaves basically like an 'init' method. It 1454 // claims the receiver and returns a retained object. 1455 addNSObjectMethSummary(GetUnarySelector("awakeAfterUsingCoder", Ctx), 1456 InitSumm); 1457 1458 // The next methods are allocators. 1459 const RetainSummary *AllocSumm = getPersistentSummary(ObjCAllocRetE); 1460 const RetainSummary *CFAllocSumm = 1461 getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true)); 1462 1463 // Create the "retain" selector. 1464 RetEffect NoRet = RetEffect::MakeNoRet(); 1465 const RetainSummary *Summ = getPersistentSummary(NoRet, IncRefMsg); 1466 addNSObjectMethSummary(GetNullarySelector("retain", Ctx), Summ); 1467 1468 // Create the "release" selector. 1469 Summ = getPersistentSummary(NoRet, DecRefMsg); 1470 addNSObjectMethSummary(GetNullarySelector("release", Ctx), Summ); 1471 1472 // Create the -dealloc summary. 1473 Summ = getPersistentSummary(NoRet, Dealloc); 1474 addNSObjectMethSummary(GetNullarySelector("dealloc", Ctx), Summ); 1475 1476 // Create the "autorelease" selector. 1477 Summ = getPersistentSummary(NoRet, Autorelease); 1478 addNSObjectMethSummary(GetNullarySelector("autorelease", Ctx), Summ); 1479 1480 // For NSWindow, allocated objects are (initially) self-owned. 1481 // FIXME: For now we opt for false negatives with NSWindow, as these objects 1482 // self-own themselves. However, they only do this once they are displayed. 1483 // Thus, we need to track an NSWindow's display status. 1484 // This is tracked in <rdar://problem/6062711>. 1485 // See also http://llvm.org/bugs/show_bug.cgi?id=3714. 1486 const RetainSummary *NoTrackYet = getPersistentSummary(RetEffect::MakeNoRet(), 1487 StopTracking, 1488 StopTracking); 1489 1490 addClassMethSummary("NSWindow", "alloc", NoTrackYet); 1491 1492 // For NSPanel (which subclasses NSWindow), allocated objects are not 1493 // self-owned. 1494 // FIXME: For now we don't track NSPanels. object for the same reason 1495 // as for NSWindow objects. 1496 addClassMethSummary("NSPanel", "alloc", NoTrackYet); 1497 1498 // Don't track allocated autorelease pools, as it is okay to prematurely 1499 // exit a method. 1500 addClassMethSummary("NSAutoreleasePool", "alloc", NoTrackYet); 1501 addClassMethSummary("NSAutoreleasePool", "allocWithZone", NoTrackYet, false); 1502 addClassMethSummary("NSAutoreleasePool", "new", NoTrackYet); 1503 1504 // Create summaries QCRenderer/QCView -createSnapShotImageOfType: 1505 addInstMethSummary("QCRenderer", AllocSumm, 1506 "createSnapshotImageOfType", NULL); 1507 addInstMethSummary("QCView", AllocSumm, 1508 "createSnapshotImageOfType", NULL); 1509 1510 // Create summaries for CIContext, 'createCGImage' and 1511 // 'createCGLayerWithSize'. These objects are CF objects, and are not 1512 // automatically garbage collected. 1513 addInstMethSummary("CIContext", CFAllocSumm, 1514 "createCGImage", "fromRect", NULL); 1515 addInstMethSummary("CIContext", CFAllocSumm, 1516 "createCGImage", "fromRect", "format", "colorSpace", NULL); 1517 addInstMethSummary("CIContext", CFAllocSumm, "createCGLayerWithSize", 1518 "info", NULL); 1519} 1520 1521//===----------------------------------------------------------------------===// 1522// Error reporting. 1523//===----------------------------------------------------------------------===// 1524namespace { 1525 typedef llvm::DenseMap<const ExplodedNode *, const RetainSummary *> 1526 SummaryLogTy; 1527 1528 //===-------------===// 1529 // Bug Descriptions. // 1530 //===-------------===// 1531 1532 class CFRefBug : public BugType { 1533 protected: 1534 CFRefBug(StringRef name) 1535 : BugType(name, categories::MemoryCoreFoundationObjectiveC) {} 1536 public: 1537 1538 // FIXME: Eventually remove. 1539 virtual const char *getDescription() const = 0; 1540 1541 virtual bool isLeak() const { return false; } 1542 }; 1543 1544 class UseAfterRelease : public CFRefBug { 1545 public: 1546 UseAfterRelease() : CFRefBug("Use-after-release") {} 1547 1548 const char *getDescription() const { 1549 return "Reference-counted object is used after it is released"; 1550 } 1551 }; 1552 1553 class BadRelease : public CFRefBug { 1554 public: 1555 BadRelease() : CFRefBug("Bad release") {} 1556 1557 const char *getDescription() const { 1558 return "Incorrect decrement of the reference count of an object that is " 1559 "not owned at this point by the caller"; 1560 } 1561 }; 1562 1563 class DeallocGC : public CFRefBug { 1564 public: 1565 DeallocGC() 1566 : CFRefBug("-dealloc called while using garbage collection") {} 1567 1568 const char *getDescription() const { 1569 return "-dealloc called while using garbage collection"; 1570 } 1571 }; 1572 1573 class DeallocNotOwned : public CFRefBug { 1574 public: 1575 DeallocNotOwned() 1576 : CFRefBug("-dealloc sent to non-exclusively owned object") {} 1577 1578 const char *getDescription() const { 1579 return "-dealloc sent to object that may be referenced elsewhere"; 1580 } 1581 }; 1582 1583 class OverAutorelease : public CFRefBug { 1584 public: 1585 OverAutorelease() 1586 : CFRefBug("Object autoreleased too many times") {} 1587 1588 const char *getDescription() const { 1589 return "Object autoreleased too many times"; 1590 } 1591 }; 1592 1593 class ReturnedNotOwnedForOwned : public CFRefBug { 1594 public: 1595 ReturnedNotOwnedForOwned() 1596 : CFRefBug("Method should return an owned object") {} 1597 1598 const char *getDescription() const { 1599 return "Object with a +0 retain count returned to caller where a +1 " 1600 "(owning) retain count is expected"; 1601 } 1602 }; 1603 1604 class Leak : public CFRefBug { 1605 public: 1606 Leak(StringRef name) 1607 : CFRefBug(name) { 1608 // Leaks should not be reported if they are post-dominated by a sink. 1609 setSuppressOnSink(true); 1610 } 1611 1612 const char *getDescription() const { return ""; } 1613 1614 bool isLeak() const { return true; } 1615 }; 1616 1617 //===---------===// 1618 // Bug Reports. // 1619 //===---------===// 1620 1621 class CFRefReportVisitor : public BugReporterVisitorImpl<CFRefReportVisitor> { 1622 protected: 1623 SymbolRef Sym; 1624 const SummaryLogTy &SummaryLog; 1625 bool GCEnabled; 1626 1627 public: 1628 CFRefReportVisitor(SymbolRef sym, bool gcEnabled, const SummaryLogTy &log) 1629 : Sym(sym), SummaryLog(log), GCEnabled(gcEnabled) {} 1630 1631 virtual void Profile(llvm::FoldingSetNodeID &ID) const { 1632 static int x = 0; 1633 ID.AddPointer(&x); 1634 ID.AddPointer(Sym); 1635 } 1636 1637 virtual PathDiagnosticPiece *VisitNode(const ExplodedNode *N, 1638 const ExplodedNode *PrevN, 1639 BugReporterContext &BRC, 1640 BugReport &BR); 1641 1642 virtual PathDiagnosticPiece *getEndPath(BugReporterContext &BRC, 1643 const ExplodedNode *N, 1644 BugReport &BR); 1645 }; 1646 1647 class CFRefLeakReportVisitor : public CFRefReportVisitor { 1648 public: 1649 CFRefLeakReportVisitor(SymbolRef sym, bool GCEnabled, 1650 const SummaryLogTy &log) 1651 : CFRefReportVisitor(sym, GCEnabled, log) {} 1652 1653 PathDiagnosticPiece *getEndPath(BugReporterContext &BRC, 1654 const ExplodedNode *N, 1655 BugReport &BR); 1656 1657 virtual BugReporterVisitor *clone() const { 1658 // The curiously-recurring template pattern only works for one level of 1659 // subclassing. Rather than make a new template base for 1660 // CFRefReportVisitor, we simply override clone() to do the right thing. 1661 // This could be trouble someday if BugReporterVisitorImpl is ever 1662 // used for something else besides a convenient implementation of clone(). 1663 return new CFRefLeakReportVisitor(*this); 1664 } 1665 }; 1666 1667 class CFRefReport : public BugReport { 1668 void addGCModeDescription(const LangOptions &LOpts, bool GCEnabled); 1669 1670 public: 1671 CFRefReport(CFRefBug &D, const LangOptions &LOpts, bool GCEnabled, 1672 const SummaryLogTy &Log, ExplodedNode *n, SymbolRef sym, 1673 bool registerVisitor = true) 1674 : BugReport(D, D.getDescription(), n) { 1675 if (registerVisitor) 1676 addVisitor(new CFRefReportVisitor(sym, GCEnabled, Log)); 1677 addGCModeDescription(LOpts, GCEnabled); 1678 } 1679 1680 CFRefReport(CFRefBug &D, const LangOptions &LOpts, bool GCEnabled, 1681 const SummaryLogTy &Log, ExplodedNode *n, SymbolRef sym, 1682 StringRef endText) 1683 : BugReport(D, D.getDescription(), endText, n) { 1684 addVisitor(new CFRefReportVisitor(sym, GCEnabled, Log)); 1685 addGCModeDescription(LOpts, GCEnabled); 1686 } 1687 1688 virtual std::pair<ranges_iterator, ranges_iterator> getRanges() { 1689 const CFRefBug& BugTy = static_cast<CFRefBug&>(getBugType()); 1690 if (!BugTy.isLeak()) 1691 return BugReport::getRanges(); 1692 else 1693 return std::make_pair(ranges_iterator(), ranges_iterator()); 1694 } 1695 }; 1696 1697 class CFRefLeakReport : public CFRefReport { 1698 const MemRegion* AllocBinding; 1699 public: 1700 CFRefLeakReport(CFRefBug &D, const LangOptions &LOpts, bool GCEnabled, 1701 const SummaryLogTy &Log, ExplodedNode *n, SymbolRef sym, 1702 CheckerContext &Ctx, 1703 bool IncludeAllocationLine); 1704 1705 PathDiagnosticLocation getLocation(const SourceManager &SM) const { 1706 assert(Location.isValid()); 1707 return Location; 1708 } 1709 }; 1710} // end anonymous namespace 1711 1712void CFRefReport::addGCModeDescription(const LangOptions &LOpts, 1713 bool GCEnabled) { 1714 const char *GCModeDescription = 0; 1715 1716 switch (LOpts.getGC()) { 1717 case LangOptions::GCOnly: 1718 assert(GCEnabled); 1719 GCModeDescription = "Code is compiled to only use garbage collection"; 1720 break; 1721 1722 case LangOptions::NonGC: 1723 assert(!GCEnabled); 1724 GCModeDescription = "Code is compiled to use reference counts"; 1725 break; 1726 1727 case LangOptions::HybridGC: 1728 if (GCEnabled) { 1729 GCModeDescription = "Code is compiled to use either garbage collection " 1730 "(GC) or reference counts (non-GC). The bug occurs " 1731 "with GC enabled"; 1732 break; 1733 } else { 1734 GCModeDescription = "Code is compiled to use either garbage collection " 1735 "(GC) or reference counts (non-GC). The bug occurs " 1736 "in non-GC mode"; 1737 break; 1738 } 1739 } 1740 1741 assert(GCModeDescription && "invalid/unknown GC mode"); 1742 addExtraText(GCModeDescription); 1743} 1744 1745static bool isNumericLiteralExpression(const Expr *E) { 1746 // FIXME: This set of cases was copied from SemaExprObjC. 1747 return isa<IntegerLiteral>(E) || 1748 isa<CharacterLiteral>(E) || 1749 isa<FloatingLiteral>(E) || 1750 isa<ObjCBoolLiteralExpr>(E) || 1751 isa<CXXBoolLiteralExpr>(E); 1752} 1753 1754PathDiagnosticPiece *CFRefReportVisitor::VisitNode(const ExplodedNode *N, 1755 const ExplodedNode *PrevN, 1756 BugReporterContext &BRC, 1757 BugReport &BR) { 1758 // FIXME: We will eventually need to handle non-statement-based events 1759 // (__attribute__((cleanup))). 1760 if (!N->getLocation().getAs<StmtPoint>()) 1761 return NULL; 1762 1763 // Check if the type state has changed. 1764 ProgramStateRef PrevSt = PrevN->getState(); 1765 ProgramStateRef CurrSt = N->getState(); 1766 const LocationContext *LCtx = N->getLocationContext(); 1767 1768 const RefVal* CurrT = getRefBinding(CurrSt, Sym); 1769 if (!CurrT) return NULL; 1770 1771 const RefVal &CurrV = *CurrT; 1772 const RefVal *PrevT = getRefBinding(PrevSt, Sym); 1773 1774 // Create a string buffer to constain all the useful things we want 1775 // to tell the user. 1776 std::string sbuf; 1777 llvm::raw_string_ostream os(sbuf); 1778 1779 // This is the allocation site since the previous node had no bindings 1780 // for this symbol. 1781 if (!PrevT) { 1782 const Stmt *S = N->getLocation().castAs<StmtPoint>().getStmt(); 1783 1784 if (isa<ObjCArrayLiteral>(S)) { 1785 os << "NSArray literal is an object with a +0 retain count"; 1786 } 1787 else if (isa<ObjCDictionaryLiteral>(S)) { 1788 os << "NSDictionary literal is an object with a +0 retain count"; 1789 } 1790 else if (const ObjCBoxedExpr *BL = dyn_cast<ObjCBoxedExpr>(S)) { 1791 if (isNumericLiteralExpression(BL->getSubExpr())) 1792 os << "NSNumber literal is an object with a +0 retain count"; 1793 else { 1794 const ObjCInterfaceDecl *BoxClass = 0; 1795 if (const ObjCMethodDecl *Method = BL->getBoxingMethod()) 1796 BoxClass = Method->getClassInterface(); 1797 1798 // We should always be able to find the boxing class interface, 1799 // but consider this future-proofing. 1800 if (BoxClass) 1801 os << *BoxClass << " b"; 1802 else 1803 os << "B"; 1804 1805 os << "oxed expression produces an object with a +0 retain count"; 1806 } 1807 } 1808 else { 1809 if (const CallExpr *CE = dyn_cast<CallExpr>(S)) { 1810 // Get the name of the callee (if it is available). 1811 SVal X = CurrSt->getSValAsScalarOrLoc(CE->getCallee(), LCtx); 1812 if (const FunctionDecl *FD = X.getAsFunctionDecl()) 1813 os << "Call to function '" << *FD << '\''; 1814 else 1815 os << "function call"; 1816 } 1817 else { 1818 assert(isa<ObjCMessageExpr>(S)); 1819 CallEventManager &Mgr = CurrSt->getStateManager().getCallEventManager(); 1820 CallEventRef<ObjCMethodCall> Call 1821 = Mgr.getObjCMethodCall(cast<ObjCMessageExpr>(S), CurrSt, LCtx); 1822 1823 switch (Call->getMessageKind()) { 1824 case OCM_Message: 1825 os << "Method"; 1826 break; 1827 case OCM_PropertyAccess: 1828 os << "Property"; 1829 break; 1830 case OCM_Subscript: 1831 os << "Subscript"; 1832 break; 1833 } 1834 } 1835 1836 if (CurrV.getObjKind() == RetEffect::CF) { 1837 os << " returns a Core Foundation object with a "; 1838 } 1839 else { 1840 assert (CurrV.getObjKind() == RetEffect::ObjC); 1841 os << " returns an Objective-C object with a "; 1842 } 1843 1844 if (CurrV.isOwned()) { 1845 os << "+1 retain count"; 1846 1847 if (GCEnabled) { 1848 assert(CurrV.getObjKind() == RetEffect::CF); 1849 os << ". " 1850 "Core Foundation objects are not automatically garbage collected."; 1851 } 1852 } 1853 else { 1854 assert (CurrV.isNotOwned()); 1855 os << "+0 retain count"; 1856 } 1857 } 1858 1859 PathDiagnosticLocation Pos(S, BRC.getSourceManager(), 1860 N->getLocationContext()); 1861 return new PathDiagnosticEventPiece(Pos, os.str()); 1862 } 1863 1864 // Gather up the effects that were performed on the object at this 1865 // program point 1866 SmallVector<ArgEffect, 2> AEffects; 1867 1868 const ExplodedNode *OrigNode = BRC.getNodeResolver().getOriginalNode(N); 1869 if (const RetainSummary *Summ = SummaryLog.lookup(OrigNode)) { 1870 // We only have summaries attached to nodes after evaluating CallExpr and 1871 // ObjCMessageExprs. 1872 const Stmt *S = N->getLocation().castAs<StmtPoint>().getStmt(); 1873 1874 if (const CallExpr *CE = dyn_cast<CallExpr>(S)) { 1875 // Iterate through the parameter expressions and see if the symbol 1876 // was ever passed as an argument. 1877 unsigned i = 0; 1878 1879 for (CallExpr::const_arg_iterator AI=CE->arg_begin(), AE=CE->arg_end(); 1880 AI!=AE; ++AI, ++i) { 1881 1882 // Retrieve the value of the argument. Is it the symbol 1883 // we are interested in? 1884 if (CurrSt->getSValAsScalarOrLoc(*AI, LCtx).getAsLocSymbol() != Sym) 1885 continue; 1886 1887 // We have an argument. Get the effect! 1888 AEffects.push_back(Summ->getArg(i)); 1889 } 1890 } 1891 else if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(S)) { 1892 if (const Expr *receiver = ME->getInstanceReceiver()) 1893 if (CurrSt->getSValAsScalarOrLoc(receiver, LCtx) 1894 .getAsLocSymbol() == Sym) { 1895 // The symbol we are tracking is the receiver. 1896 AEffects.push_back(Summ->getReceiverEffect()); 1897 } 1898 } 1899 } 1900 1901 do { 1902 // Get the previous type state. 1903 RefVal PrevV = *PrevT; 1904 1905 // Specially handle -dealloc. 1906 if (!GCEnabled && std::find(AEffects.begin(), AEffects.end(), Dealloc) != 1907 AEffects.end()) { 1908 // Determine if the object's reference count was pushed to zero. 1909 assert(!(PrevV == CurrV) && "The typestate *must* have changed."); 1910 // We may not have transitioned to 'release' if we hit an error. 1911 // This case is handled elsewhere. 1912 if (CurrV.getKind() == RefVal::Released) { 1913 assert(CurrV.getCombinedCounts() == 0); 1914 os << "Object released by directly sending the '-dealloc' message"; 1915 break; 1916 } 1917 } 1918 1919 // Specially handle CFMakeCollectable and friends. 1920 if (std::find(AEffects.begin(), AEffects.end(), MakeCollectable) != 1921 AEffects.end()) { 1922 // Get the name of the function. 1923 const Stmt *S = N->getLocation().castAs<StmtPoint>().getStmt(); 1924 SVal X = 1925 CurrSt->getSValAsScalarOrLoc(cast<CallExpr>(S)->getCallee(), LCtx); 1926 const FunctionDecl *FD = X.getAsFunctionDecl(); 1927 1928 if (GCEnabled) { 1929 // Determine if the object's reference count was pushed to zero. 1930 assert(!(PrevV == CurrV) && "The typestate *must* have changed."); 1931 1932 os << "In GC mode a call to '" << *FD 1933 << "' decrements an object's retain count and registers the " 1934 "object with the garbage collector. "; 1935 1936 if (CurrV.getKind() == RefVal::Released) { 1937 assert(CurrV.getCount() == 0); 1938 os << "Since it now has a 0 retain count the object can be " 1939 "automatically collected by the garbage collector."; 1940 } 1941 else 1942 os << "An object must have a 0 retain count to be garbage collected. " 1943 "After this call its retain count is +" << CurrV.getCount() 1944 << '.'; 1945 } 1946 else 1947 os << "When GC is not enabled a call to '" << *FD 1948 << "' has no effect on its argument."; 1949 1950 // Nothing more to say. 1951 break; 1952 } 1953 1954 // Determine if the typestate has changed. 1955 if (!(PrevV == CurrV)) 1956 switch (CurrV.getKind()) { 1957 case RefVal::Owned: 1958 case RefVal::NotOwned: 1959 1960 if (PrevV.getCount() == CurrV.getCount()) { 1961 // Did an autorelease message get sent? 1962 if (PrevV.getAutoreleaseCount() == CurrV.getAutoreleaseCount()) 1963 return 0; 1964 1965 assert(PrevV.getAutoreleaseCount() < CurrV.getAutoreleaseCount()); 1966 os << "Object autoreleased"; 1967 break; 1968 } 1969 1970 if (PrevV.getCount() > CurrV.getCount()) 1971 os << "Reference count decremented."; 1972 else 1973 os << "Reference count incremented."; 1974 1975 if (unsigned Count = CurrV.getCount()) 1976 os << " The object now has a +" << Count << " retain count."; 1977 1978 if (PrevV.getKind() == RefVal::Released) { 1979 assert(GCEnabled && CurrV.getCount() > 0); 1980 os << " The object is not eligible for garbage collection until " 1981 "the retain count reaches 0 again."; 1982 } 1983 1984 break; 1985 1986 case RefVal::Released: 1987 os << "Object released."; 1988 break; 1989 1990 case RefVal::ReturnedOwned: 1991 // Autoreleases can be applied after marking a node ReturnedOwned. 1992 if (CurrV.getAutoreleaseCount()) 1993 return NULL; 1994 1995 os << "Object returned to caller as an owning reference (single " 1996 "retain count transferred to caller)"; 1997 break; 1998 1999 case RefVal::ReturnedNotOwned: 2000 os << "Object returned to caller with a +0 retain count"; 2001 break; 2002 2003 default: 2004 return NULL; 2005 } 2006 2007 // Emit any remaining diagnostics for the argument effects (if any). 2008 for (SmallVectorImpl<ArgEffect>::iterator I=AEffects.begin(), 2009 E=AEffects.end(); I != E; ++I) { 2010 2011 // A bunch of things have alternate behavior under GC. 2012 if (GCEnabled) 2013 switch (*I) { 2014 default: break; 2015 case Autorelease: 2016 os << "In GC mode an 'autorelease' has no effect."; 2017 continue; 2018 case IncRefMsg: 2019 os << "In GC mode the 'retain' message has no effect."; 2020 continue; 2021 case DecRefMsg: 2022 os << "In GC mode the 'release' message has no effect."; 2023 continue; 2024 } 2025 } 2026 } while (0); 2027 2028 if (os.str().empty()) 2029 return 0; // We have nothing to say! 2030 2031 const Stmt *S = N->getLocation().castAs<StmtPoint>().getStmt(); 2032 PathDiagnosticLocation Pos(S, BRC.getSourceManager(), 2033 N->getLocationContext()); 2034 PathDiagnosticPiece *P = new PathDiagnosticEventPiece(Pos, os.str()); 2035 2036 // Add the range by scanning the children of the statement for any bindings 2037 // to Sym. 2038 for (Stmt::const_child_iterator I = S->child_begin(), E = S->child_end(); 2039 I!=E; ++I) 2040 if (const Expr *Exp = dyn_cast_or_null<Expr>(*I)) 2041 if (CurrSt->getSValAsScalarOrLoc(Exp, LCtx).getAsLocSymbol() == Sym) { 2042 P->addRange(Exp->getSourceRange()); 2043 break; 2044 } 2045 2046 return P; 2047} 2048 2049// Find the first node in the current function context that referred to the 2050// tracked symbol and the memory location that value was stored to. Note, the 2051// value is only reported if the allocation occurred in the same function as 2052// the leak. The function can also return a location context, which should be 2053// treated as interesting. 2054struct AllocationInfo { 2055 const ExplodedNode* N; 2056 const MemRegion *R; 2057 const LocationContext *InterestingMethodContext; 2058 AllocationInfo(const ExplodedNode *InN, 2059 const MemRegion *InR, 2060 const LocationContext *InInterestingMethodContext) : 2061 N(InN), R(InR), InterestingMethodContext(InInterestingMethodContext) {} 2062}; 2063 2064static AllocationInfo 2065GetAllocationSite(ProgramStateManager& StateMgr, const ExplodedNode *N, 2066 SymbolRef Sym) { 2067 const ExplodedNode *AllocationNode = N; 2068 const ExplodedNode *AllocationNodeInCurrentContext = N; 2069 const MemRegion* FirstBinding = 0; 2070 const LocationContext *LeakContext = N->getLocationContext(); 2071 2072 // The location context of the init method called on the leaked object, if 2073 // available. 2074 const LocationContext *InitMethodContext = 0; 2075 2076 while (N) { 2077 ProgramStateRef St = N->getState(); 2078 const LocationContext *NContext = N->getLocationContext(); 2079 2080 if (!getRefBinding(St, Sym)) 2081 break; 2082 2083 StoreManager::FindUniqueBinding FB(Sym); 2084 StateMgr.iterBindings(St, FB); 2085 2086 if (FB) { 2087 const MemRegion *R = FB.getRegion(); 2088 const VarRegion *VR = R->getBaseRegion()->getAs<VarRegion>(); 2089 // Do not show local variables belonging to a function other than 2090 // where the error is reported. 2091 if (!VR || VR->getStackFrame() == LeakContext->getCurrentStackFrame()) 2092 FirstBinding = R; 2093 } 2094 2095 // AllocationNode is the last node in which the symbol was tracked. 2096 AllocationNode = N; 2097 2098 // AllocationNodeInCurrentContext, is the last node in the current context 2099 // in which the symbol was tracked. 2100 if (NContext == LeakContext) 2101 AllocationNodeInCurrentContext = N; 2102 2103 // Find the last init that was called on the given symbol and store the 2104 // init method's location context. 2105 if (!InitMethodContext) 2106 if (Optional<CallEnter> CEP = N->getLocation().getAs<CallEnter>()) { 2107 const Stmt *CE = CEP->getCallExpr(); 2108 if (const ObjCMessageExpr *ME = dyn_cast_or_null<ObjCMessageExpr>(CE)) { 2109 const Stmt *RecExpr = ME->getInstanceReceiver(); 2110 if (RecExpr) { 2111 SVal RecV = St->getSVal(RecExpr, NContext); 2112 if (ME->getMethodFamily() == OMF_init && RecV.getAsSymbol() == Sym) 2113 InitMethodContext = CEP->getCalleeContext(); 2114 } 2115 } 2116 } 2117 2118 N = N->pred_empty() ? NULL : *(N->pred_begin()); 2119 } 2120 2121 // If we are reporting a leak of the object that was allocated with alloc, 2122 // mark its init method as interesting. 2123 const LocationContext *InterestingMethodContext = 0; 2124 if (InitMethodContext) { 2125 const ProgramPoint AllocPP = AllocationNode->getLocation(); 2126 if (Optional<StmtPoint> SP = AllocPP.getAs<StmtPoint>()) 2127 if (const ObjCMessageExpr *ME = SP->getStmtAs<ObjCMessageExpr>()) 2128 if (ME->getMethodFamily() == OMF_alloc) 2129 InterestingMethodContext = InitMethodContext; 2130 } 2131 2132 // If allocation happened in a function different from the leak node context, 2133 // do not report the binding. 2134 assert(N && "Could not find allocation node"); 2135 if (N->getLocationContext() != LeakContext) { 2136 FirstBinding = 0; 2137 } 2138 2139 return AllocationInfo(AllocationNodeInCurrentContext, 2140 FirstBinding, 2141 InterestingMethodContext); 2142} 2143 2144PathDiagnosticPiece* 2145CFRefReportVisitor::getEndPath(BugReporterContext &BRC, 2146 const ExplodedNode *EndN, 2147 BugReport &BR) { 2148 BR.markInteresting(Sym); 2149 return BugReporterVisitor::getDefaultEndPath(BRC, EndN, BR); 2150} 2151 2152PathDiagnosticPiece* 2153CFRefLeakReportVisitor::getEndPath(BugReporterContext &BRC, 2154 const ExplodedNode *EndN, 2155 BugReport &BR) { 2156 2157 // Tell the BugReporterContext to report cases when the tracked symbol is 2158 // assigned to different variables, etc. 2159 BR.markInteresting(Sym); 2160 2161 // We are reporting a leak. Walk up the graph to get to the first node where 2162 // the symbol appeared, and also get the first VarDecl that tracked object 2163 // is stored to. 2164 AllocationInfo AllocI = 2165 GetAllocationSite(BRC.getStateManager(), EndN, Sym); 2166 2167 const MemRegion* FirstBinding = AllocI.R; 2168 BR.markInteresting(AllocI.InterestingMethodContext); 2169 2170 SourceManager& SM = BRC.getSourceManager(); 2171 2172 // Compute an actual location for the leak. Sometimes a leak doesn't 2173 // occur at an actual statement (e.g., transition between blocks; end 2174 // of function) so we need to walk the graph and compute a real location. 2175 const ExplodedNode *LeakN = EndN; 2176 PathDiagnosticLocation L = PathDiagnosticLocation::createEndOfPath(LeakN, SM); 2177 2178 std::string sbuf; 2179 llvm::raw_string_ostream os(sbuf); 2180 2181 os << "Object leaked: "; 2182 2183 if (FirstBinding) { 2184 os << "object allocated and stored into '" 2185 << FirstBinding->getString() << '\''; 2186 } 2187 else 2188 os << "allocated object"; 2189 2190 // Get the retain count. 2191 const RefVal* RV = getRefBinding(EndN->getState(), Sym); 2192 assert(RV); 2193 2194 if (RV->getKind() == RefVal::ErrorLeakReturned) { 2195 // FIXME: Per comments in rdar://6320065, "create" only applies to CF 2196 // objects. Only "copy", "alloc", "retain" and "new" transfer ownership 2197 // to the caller for NS objects. 2198 const Decl *D = &EndN->getCodeDecl(); 2199 2200 os << (isa<ObjCMethodDecl>(D) ? " is returned from a method " 2201 : " is returned from a function "); 2202 2203 if (D->getAttr<CFReturnsNotRetainedAttr>()) 2204 os << "that is annotated as CF_RETURNS_NOT_RETAINED"; 2205 else if (D->getAttr<NSReturnsNotRetainedAttr>()) 2206 os << "that is annotated as NS_RETURNS_NOT_RETAINED"; 2207 else { 2208 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 2209 os << "whose name ('" << MD->getSelector().getAsString() 2210 << "') does not start with 'copy', 'mutableCopy', 'alloc' or 'new'." 2211 " This violates the naming convention rules" 2212 " given in the Memory Management Guide for Cocoa"; 2213 } 2214 else { 2215 const FunctionDecl *FD = cast<FunctionDecl>(D); 2216 os << "whose name ('" << *FD 2217 << "') does not contain 'Copy' or 'Create'. This violates the naming" 2218 " convention rules given in the Memory Management Guide for Core" 2219 " Foundation"; 2220 } 2221 } 2222 } 2223 else if (RV->getKind() == RefVal::ErrorGCLeakReturned) { 2224 const ObjCMethodDecl &MD = cast<ObjCMethodDecl>(EndN->getCodeDecl()); 2225 os << " and returned from method '" << MD.getSelector().getAsString() 2226 << "' is potentially leaked when using garbage collection. Callers " 2227 "of this method do not expect a returned object with a +1 retain " 2228 "count since they expect the object to be managed by the garbage " 2229 "collector"; 2230 } 2231 else 2232 os << " is not referenced later in this execution path and has a retain " 2233 "count of +" << RV->getCount(); 2234 2235 return new PathDiagnosticEventPiece(L, os.str()); 2236} 2237 2238CFRefLeakReport::CFRefLeakReport(CFRefBug &D, const LangOptions &LOpts, 2239 bool GCEnabled, const SummaryLogTy &Log, 2240 ExplodedNode *n, SymbolRef sym, 2241 CheckerContext &Ctx, 2242 bool IncludeAllocationLine) 2243 : CFRefReport(D, LOpts, GCEnabled, Log, n, sym, false) { 2244 2245 // Most bug reports are cached at the location where they occurred. 2246 // With leaks, we want to unique them by the location where they were 2247 // allocated, and only report a single path. To do this, we need to find 2248 // the allocation site of a piece of tracked memory, which we do via a 2249 // call to GetAllocationSite. This will walk the ExplodedGraph backwards. 2250 // Note that this is *not* the trimmed graph; we are guaranteed, however, 2251 // that all ancestor nodes that represent the allocation site have the 2252 // same SourceLocation. 2253 const ExplodedNode *AllocNode = 0; 2254 2255 const SourceManager& SMgr = Ctx.getSourceManager(); 2256 2257 AllocationInfo AllocI = 2258 GetAllocationSite(Ctx.getStateManager(), getErrorNode(), sym); 2259 2260 AllocNode = AllocI.N; 2261 AllocBinding = AllocI.R; 2262 markInteresting(AllocI.InterestingMethodContext); 2263 2264 // Get the SourceLocation for the allocation site. 2265 // FIXME: This will crash the analyzer if an allocation comes from an 2266 // implicit call. (Currently there are no such allocations in Cocoa, though.) 2267 const Stmt *AllocStmt; 2268 ProgramPoint P = AllocNode->getLocation(); 2269 if (Optional<CallExitEnd> Exit = P.getAs<CallExitEnd>()) 2270 AllocStmt = Exit->getCalleeContext()->getCallSite(); 2271 else 2272 AllocStmt = P.castAs<PostStmt>().getStmt(); 2273 assert(AllocStmt && "All allocations must come from explicit calls"); 2274 2275 PathDiagnosticLocation AllocLocation = 2276 PathDiagnosticLocation::createBegin(AllocStmt, SMgr, 2277 AllocNode->getLocationContext()); 2278 Location = AllocLocation; 2279 2280 // Set uniqieing info, which will be used for unique the bug reports. The 2281 // leaks should be uniqued on the allocation site. 2282 UniqueingLocation = AllocLocation; 2283 UniqueingDecl = AllocNode->getLocationContext()->getDecl(); 2284 2285 // Fill in the description of the bug. 2286 Description.clear(); 2287 llvm::raw_string_ostream os(Description); 2288 os << "Potential leak "; 2289 if (GCEnabled) 2290 os << "(when using garbage collection) "; 2291 os << "of an object"; 2292 2293 if (AllocBinding) { 2294 os << " stored into '" << AllocBinding->getString() << '\''; 2295 if (IncludeAllocationLine) { 2296 FullSourceLoc SL(AllocStmt->getLocStart(), Ctx.getSourceManager()); 2297 os << " (allocated on line " << SL.getSpellingLineNumber() << ")"; 2298 } 2299 } 2300 2301 addVisitor(new CFRefLeakReportVisitor(sym, GCEnabled, Log)); 2302} 2303 2304//===----------------------------------------------------------------------===// 2305// Main checker logic. 2306//===----------------------------------------------------------------------===// 2307 2308namespace { 2309class RetainCountChecker 2310 : public Checker< check::Bind, 2311 check::DeadSymbols, 2312 check::EndAnalysis, 2313 check::EndFunction, 2314 check::PostStmt<BlockExpr>, 2315 check::PostStmt<CastExpr>, 2316 check::PostStmt<ObjCArrayLiteral>, 2317 check::PostStmt<ObjCDictionaryLiteral>, 2318 check::PostStmt<ObjCBoxedExpr>, 2319 check::PostCall, 2320 check::PreStmt<ReturnStmt>, 2321 check::RegionChanges, 2322 eval::Assume, 2323 eval::Call > { 2324 mutable OwningPtr<CFRefBug> useAfterRelease, releaseNotOwned; 2325 mutable OwningPtr<CFRefBug> deallocGC, deallocNotOwned; 2326 mutable OwningPtr<CFRefBug> overAutorelease, returnNotOwnedForOwned; 2327 mutable OwningPtr<CFRefBug> leakWithinFunction, leakAtReturn; 2328 mutable OwningPtr<CFRefBug> leakWithinFunctionGC, leakAtReturnGC; 2329 2330 typedef llvm::DenseMap<SymbolRef, const SimpleProgramPointTag *> SymbolTagMap; 2331 2332 // This map is only used to ensure proper deletion of any allocated tags. 2333 mutable SymbolTagMap DeadSymbolTags; 2334 2335 mutable OwningPtr<RetainSummaryManager> Summaries; 2336 mutable OwningPtr<RetainSummaryManager> SummariesGC; 2337 mutable SummaryLogTy SummaryLog; 2338 mutable bool ShouldResetSummaryLog; 2339 2340 /// Optional setting to indicate if leak reports should include 2341 /// the allocation line. 2342 mutable bool IncludeAllocationLine; 2343 2344public: 2345 RetainCountChecker(AnalyzerOptions &AO) 2346 : ShouldResetSummaryLog(false), 2347 IncludeAllocationLine(shouldIncludeAllocationSiteInLeakDiagnostics(AO)) {} 2348 2349 virtual ~RetainCountChecker() { 2350 DeleteContainerSeconds(DeadSymbolTags); 2351 } 2352 2353 void checkEndAnalysis(ExplodedGraph &G, BugReporter &BR, 2354 ExprEngine &Eng) const { 2355 // FIXME: This is a hack to make sure the summary log gets cleared between 2356 // analyses of different code bodies. 2357 // 2358 // Why is this necessary? Because a checker's lifetime is tied to a 2359 // translation unit, but an ExplodedGraph's lifetime is just a code body. 2360 // Once in a blue moon, a new ExplodedNode will have the same address as an 2361 // old one with an associated summary, and the bug report visitor gets very 2362 // confused. (To make things worse, the summary lifetime is currently also 2363 // tied to a code body, so we get a crash instead of incorrect results.) 2364 // 2365 // Why is this a bad solution? Because if the lifetime of the ExplodedGraph 2366 // changes, things will start going wrong again. Really the lifetime of this 2367 // log needs to be tied to either the specific nodes in it or the entire 2368 // ExplodedGraph, not to a specific part of the code being analyzed. 2369 // 2370 // (Also, having stateful local data means that the same checker can't be 2371 // used from multiple threads, but a lot of checkers have incorrect 2372 // assumptions about that anyway. So that wasn't a priority at the time of 2373 // this fix.) 2374 // 2375 // This happens at the end of analysis, but bug reports are emitted /after/ 2376 // this point. So we can't just clear the summary log now. Instead, we mark 2377 // that the next time we access the summary log, it should be cleared. 2378 2379 // If we never reset the summary log during /this/ code body analysis, 2380 // there were no new summaries. There might still have been summaries from 2381 // the /last/ analysis, so clear them out to make sure the bug report 2382 // visitors don't get confused. 2383 if (ShouldResetSummaryLog) 2384 SummaryLog.clear(); 2385 2386 ShouldResetSummaryLog = !SummaryLog.empty(); 2387 } 2388 2389 CFRefBug *getLeakWithinFunctionBug(const LangOptions &LOpts, 2390 bool GCEnabled) const { 2391 if (GCEnabled) { 2392 if (!leakWithinFunctionGC) 2393 leakWithinFunctionGC.reset(new Leak("Leak of object when using " 2394 "garbage collection")); 2395 return leakWithinFunctionGC.get(); 2396 } else { 2397 if (!leakWithinFunction) { 2398 if (LOpts.getGC() == LangOptions::HybridGC) { 2399 leakWithinFunction.reset(new Leak("Leak of object when not using " 2400 "garbage collection (GC) in " 2401 "dual GC/non-GC code")); 2402 } else { 2403 leakWithinFunction.reset(new Leak("Leak")); 2404 } 2405 } 2406 return leakWithinFunction.get(); 2407 } 2408 } 2409 2410 CFRefBug *getLeakAtReturnBug(const LangOptions &LOpts, bool GCEnabled) const { 2411 if (GCEnabled) { 2412 if (!leakAtReturnGC) 2413 leakAtReturnGC.reset(new Leak("Leak of returned object when using " 2414 "garbage collection")); 2415 return leakAtReturnGC.get(); 2416 } else { 2417 if (!leakAtReturn) { 2418 if (LOpts.getGC() == LangOptions::HybridGC) { 2419 leakAtReturn.reset(new Leak("Leak of returned object when not using " 2420 "garbage collection (GC) in dual " 2421 "GC/non-GC code")); 2422 } else { 2423 leakAtReturn.reset(new Leak("Leak of returned object")); 2424 } 2425 } 2426 return leakAtReturn.get(); 2427 } 2428 } 2429 2430 RetainSummaryManager &getSummaryManager(ASTContext &Ctx, 2431 bool GCEnabled) const { 2432 // FIXME: We don't support ARC being turned on and off during one analysis. 2433 // (nor, for that matter, do we support changing ASTContexts) 2434 bool ARCEnabled = (bool)Ctx.getLangOpts().ObjCAutoRefCount; 2435 if (GCEnabled) { 2436 if (!SummariesGC) 2437 SummariesGC.reset(new RetainSummaryManager(Ctx, true, ARCEnabled)); 2438 else 2439 assert(SummariesGC->isARCEnabled() == ARCEnabled); 2440 return *SummariesGC; 2441 } else { 2442 if (!Summaries) 2443 Summaries.reset(new RetainSummaryManager(Ctx, false, ARCEnabled)); 2444 else 2445 assert(Summaries->isARCEnabled() == ARCEnabled); 2446 return *Summaries; 2447 } 2448 } 2449 2450 RetainSummaryManager &getSummaryManager(CheckerContext &C) const { 2451 return getSummaryManager(C.getASTContext(), C.isObjCGCEnabled()); 2452 } 2453 2454 void printState(raw_ostream &Out, ProgramStateRef State, 2455 const char *NL, const char *Sep) const; 2456 2457 void checkBind(SVal loc, SVal val, const Stmt *S, CheckerContext &C) const; 2458 void checkPostStmt(const BlockExpr *BE, CheckerContext &C) const; 2459 void checkPostStmt(const CastExpr *CE, CheckerContext &C) const; 2460 2461 void checkPostStmt(const ObjCArrayLiteral *AL, CheckerContext &C) const; 2462 void checkPostStmt(const ObjCDictionaryLiteral *DL, CheckerContext &C) const; 2463 void checkPostStmt(const ObjCBoxedExpr *BE, CheckerContext &C) const; 2464 2465 void checkPostCall(const CallEvent &Call, CheckerContext &C) const; 2466 2467 void checkSummary(const RetainSummary &Summ, const CallEvent &Call, 2468 CheckerContext &C) const; 2469 2470 void processSummaryOfInlined(const RetainSummary &Summ, 2471 const CallEvent &Call, 2472 CheckerContext &C) const; 2473 2474 bool evalCall(const CallExpr *CE, CheckerContext &C) const; 2475 2476 ProgramStateRef evalAssume(ProgramStateRef state, SVal Cond, 2477 bool Assumption) const; 2478 2479 ProgramStateRef 2480 checkRegionChanges(ProgramStateRef state, 2481 const InvalidatedSymbols *invalidated, 2482 ArrayRef<const MemRegion *> ExplicitRegions, 2483 ArrayRef<const MemRegion *> Regions, 2484 const CallEvent *Call) const; 2485 2486 bool wantsRegionChangeUpdate(ProgramStateRef state) const { 2487 return true; 2488 } 2489 2490 void checkPreStmt(const ReturnStmt *S, CheckerContext &C) const; 2491 void checkReturnWithRetEffect(const ReturnStmt *S, CheckerContext &C, 2492 ExplodedNode *Pred, RetEffect RE, RefVal X, 2493 SymbolRef Sym, ProgramStateRef state) const; 2494 2495 void checkDeadSymbols(SymbolReaper &SymReaper, CheckerContext &C) const; 2496 void checkEndFunction(CheckerContext &C) const; 2497 2498 ProgramStateRef updateSymbol(ProgramStateRef state, SymbolRef sym, 2499 RefVal V, ArgEffect E, RefVal::Kind &hasErr, 2500 CheckerContext &C) const; 2501 2502 void processNonLeakError(ProgramStateRef St, SourceRange ErrorRange, 2503 RefVal::Kind ErrorKind, SymbolRef Sym, 2504 CheckerContext &C) const; 2505 2506 void processObjCLiterals(CheckerContext &C, const Expr *Ex) const; 2507 2508 const ProgramPointTag *getDeadSymbolTag(SymbolRef sym) const; 2509 2510 ProgramStateRef handleSymbolDeath(ProgramStateRef state, 2511 SymbolRef sid, RefVal V, 2512 SmallVectorImpl<SymbolRef> &Leaked) const; 2513 2514 ProgramStateRef 2515 handleAutoreleaseCounts(ProgramStateRef state, ExplodedNode *Pred, 2516 const ProgramPointTag *Tag, CheckerContext &Ctx, 2517 SymbolRef Sym, RefVal V) const; 2518 2519 ExplodedNode *processLeaks(ProgramStateRef state, 2520 SmallVectorImpl<SymbolRef> &Leaked, 2521 CheckerContext &Ctx, 2522 ExplodedNode *Pred = 0) const; 2523}; 2524} // end anonymous namespace 2525 2526namespace { 2527class StopTrackingCallback : public SymbolVisitor { 2528 ProgramStateRef state; 2529public: 2530 StopTrackingCallback(ProgramStateRef st) : state(st) {} 2531 ProgramStateRef getState() const { return state; } 2532 2533 bool VisitSymbol(SymbolRef sym) { 2534 state = state->remove<RefBindings>(sym); 2535 return true; 2536 } 2537}; 2538} // end anonymous namespace 2539 2540//===----------------------------------------------------------------------===// 2541// Handle statements that may have an effect on refcounts. 2542//===----------------------------------------------------------------------===// 2543 2544void RetainCountChecker::checkPostStmt(const BlockExpr *BE, 2545 CheckerContext &C) const { 2546 2547 // Scan the BlockDecRefExprs for any object the retain count checker 2548 // may be tracking. 2549 if (!BE->getBlockDecl()->hasCaptures()) 2550 return; 2551 2552 ProgramStateRef state = C.getState(); 2553 const BlockDataRegion *R = 2554 cast<BlockDataRegion>(state->getSVal(BE, 2555 C.getLocationContext()).getAsRegion()); 2556 2557 BlockDataRegion::referenced_vars_iterator I = R->referenced_vars_begin(), 2558 E = R->referenced_vars_end(); 2559 2560 if (I == E) 2561 return; 2562 2563 // FIXME: For now we invalidate the tracking of all symbols passed to blocks 2564 // via captured variables, even though captured variables result in a copy 2565 // and in implicit increment/decrement of a retain count. 2566 SmallVector<const MemRegion*, 10> Regions; 2567 const LocationContext *LC = C.getLocationContext(); 2568 MemRegionManager &MemMgr = C.getSValBuilder().getRegionManager(); 2569 2570 for ( ; I != E; ++I) { 2571 const VarRegion *VR = I.getCapturedRegion(); 2572 if (VR->getSuperRegion() == R) { 2573 VR = MemMgr.getVarRegion(VR->getDecl(), LC); 2574 } 2575 Regions.push_back(VR); 2576 } 2577 2578 state = 2579 state->scanReachableSymbols<StopTrackingCallback>(Regions.data(), 2580 Regions.data() + Regions.size()).getState(); 2581 C.addTransition(state); 2582} 2583 2584void RetainCountChecker::checkPostStmt(const CastExpr *CE, 2585 CheckerContext &C) const { 2586 const ObjCBridgedCastExpr *BE = dyn_cast<ObjCBridgedCastExpr>(CE); 2587 if (!BE) 2588 return; 2589 2590 ArgEffect AE = IncRef; 2591 2592 switch (BE->getBridgeKind()) { 2593 case clang::OBC_Bridge: 2594 // Do nothing. 2595 return; 2596 case clang::OBC_BridgeRetained: 2597 AE = IncRef; 2598 break; 2599 case clang::OBC_BridgeTransfer: 2600 AE = DecRefBridgedTransfered; 2601 break; 2602 } 2603 2604 ProgramStateRef state = C.getState(); 2605 SymbolRef Sym = state->getSVal(CE, C.getLocationContext()).getAsLocSymbol(); 2606 if (!Sym) 2607 return; 2608 const RefVal* T = getRefBinding(state, Sym); 2609 if (!T) 2610 return; 2611 2612 RefVal::Kind hasErr = (RefVal::Kind) 0; 2613 state = updateSymbol(state, Sym, *T, AE, hasErr, C); 2614 2615 if (hasErr) { 2616 // FIXME: If we get an error during a bridge cast, should we report it? 2617 // Should we assert that there is no error? 2618 return; 2619 } 2620 2621 C.addTransition(state); 2622} 2623 2624void RetainCountChecker::processObjCLiterals(CheckerContext &C, 2625 const Expr *Ex) const { 2626 ProgramStateRef state = C.getState(); 2627 const ExplodedNode *pred = C.getPredecessor(); 2628 for (Stmt::const_child_iterator it = Ex->child_begin(), et = Ex->child_end() ; 2629 it != et ; ++it) { 2630 const Stmt *child = *it; 2631 SVal V = state->getSVal(child, pred->getLocationContext()); 2632 if (SymbolRef sym = V.getAsSymbol()) 2633 if (const RefVal* T = getRefBinding(state, sym)) { 2634 RefVal::Kind hasErr = (RefVal::Kind) 0; 2635 state = updateSymbol(state, sym, *T, MayEscape, hasErr, C); 2636 if (hasErr) { 2637 processNonLeakError(state, child->getSourceRange(), hasErr, sym, C); 2638 return; 2639 } 2640 } 2641 } 2642 2643 // Return the object as autoreleased. 2644 // RetEffect RE = RetEffect::MakeNotOwned(RetEffect::ObjC); 2645 if (SymbolRef sym = 2646 state->getSVal(Ex, pred->getLocationContext()).getAsSymbol()) { 2647 QualType ResultTy = Ex->getType(); 2648 state = setRefBinding(state, sym, 2649 RefVal::makeNotOwned(RetEffect::ObjC, ResultTy)); 2650 } 2651 2652 C.addTransition(state); 2653} 2654 2655void RetainCountChecker::checkPostStmt(const ObjCArrayLiteral *AL, 2656 CheckerContext &C) const { 2657 // Apply the 'MayEscape' to all values. 2658 processObjCLiterals(C, AL); 2659} 2660 2661void RetainCountChecker::checkPostStmt(const ObjCDictionaryLiteral *DL, 2662 CheckerContext &C) const { 2663 // Apply the 'MayEscape' to all keys and values. 2664 processObjCLiterals(C, DL); 2665} 2666 2667void RetainCountChecker::checkPostStmt(const ObjCBoxedExpr *Ex, 2668 CheckerContext &C) const { 2669 const ExplodedNode *Pred = C.getPredecessor(); 2670 const LocationContext *LCtx = Pred->getLocationContext(); 2671 ProgramStateRef State = Pred->getState(); 2672 2673 if (SymbolRef Sym = State->getSVal(Ex, LCtx).getAsSymbol()) { 2674 QualType ResultTy = Ex->getType(); 2675 State = setRefBinding(State, Sym, 2676 RefVal::makeNotOwned(RetEffect::ObjC, ResultTy)); 2677 } 2678 2679 C.addTransition(State); 2680} 2681 2682void RetainCountChecker::checkPostCall(const CallEvent &Call, 2683 CheckerContext &C) const { 2684 RetainSummaryManager &Summaries = getSummaryManager(C); 2685 const RetainSummary *Summ = Summaries.getSummary(Call, C.getState()); 2686 2687 if (C.wasInlined) { 2688 processSummaryOfInlined(*Summ, Call, C); 2689 return; 2690 } 2691 checkSummary(*Summ, Call, C); 2692} 2693 2694/// GetReturnType - Used to get the return type of a message expression or 2695/// function call with the intention of affixing that type to a tracked symbol. 2696/// While the return type can be queried directly from RetEx, when 2697/// invoking class methods we augment to the return type to be that of 2698/// a pointer to the class (as opposed it just being id). 2699// FIXME: We may be able to do this with related result types instead. 2700// This function is probably overestimating. 2701static QualType GetReturnType(const Expr *RetE, ASTContext &Ctx) { 2702 QualType RetTy = RetE->getType(); 2703 // If RetE is not a message expression just return its type. 2704 // If RetE is a message expression, return its types if it is something 2705 /// more specific than id. 2706 if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(RetE)) 2707 if (const ObjCObjectPointerType *PT = RetTy->getAs<ObjCObjectPointerType>()) 2708 if (PT->isObjCQualifiedIdType() || PT->isObjCIdType() || 2709 PT->isObjCClassType()) { 2710 // At this point we know the return type of the message expression is 2711 // id, id<...>, or Class. If we have an ObjCInterfaceDecl, we know this 2712 // is a call to a class method whose type we can resolve. In such 2713 // cases, promote the return type to XXX* (where XXX is the class). 2714 const ObjCInterfaceDecl *D = ME->getReceiverInterface(); 2715 return !D ? RetTy : 2716 Ctx.getObjCObjectPointerType(Ctx.getObjCInterfaceType(D)); 2717 } 2718 2719 return RetTy; 2720} 2721 2722// We don't always get the exact modeling of the function with regards to the 2723// retain count checker even when the function is inlined. For example, we need 2724// to stop tracking the symbols which were marked with StopTrackingHard. 2725void RetainCountChecker::processSummaryOfInlined(const RetainSummary &Summ, 2726 const CallEvent &CallOrMsg, 2727 CheckerContext &C) const { 2728 ProgramStateRef state = C.getState(); 2729 2730 // Evaluate the effect of the arguments. 2731 for (unsigned idx = 0, e = CallOrMsg.getNumArgs(); idx != e; ++idx) { 2732 if (Summ.getArg(idx) == StopTrackingHard) { 2733 SVal V = CallOrMsg.getArgSVal(idx); 2734 if (SymbolRef Sym = V.getAsLocSymbol()) { 2735 state = removeRefBinding(state, Sym); 2736 } 2737 } 2738 } 2739 2740 // Evaluate the effect on the message receiver. 2741 const ObjCMethodCall *MsgInvocation = dyn_cast<ObjCMethodCall>(&CallOrMsg); 2742 if (MsgInvocation) { 2743 if (SymbolRef Sym = MsgInvocation->getReceiverSVal().getAsLocSymbol()) { 2744 if (Summ.getReceiverEffect() == StopTrackingHard) { 2745 state = removeRefBinding(state, Sym); 2746 } 2747 } 2748 } 2749 2750 // Consult the summary for the return value. 2751 RetEffect RE = Summ.getRetEffect(); 2752 if (RE.getKind() == RetEffect::NoRetHard) { 2753 SymbolRef Sym = CallOrMsg.getReturnValue().getAsSymbol(); 2754 if (Sym) 2755 state = removeRefBinding(state, Sym); 2756 } 2757 2758 C.addTransition(state); 2759} 2760 2761void RetainCountChecker::checkSummary(const RetainSummary &Summ, 2762 const CallEvent &CallOrMsg, 2763 CheckerContext &C) const { 2764 ProgramStateRef state = C.getState(); 2765 2766 // Evaluate the effect of the arguments. 2767 RefVal::Kind hasErr = (RefVal::Kind) 0; 2768 SourceRange ErrorRange; 2769 SymbolRef ErrorSym = 0; 2770 2771 for (unsigned idx = 0, e = CallOrMsg.getNumArgs(); idx != e; ++idx) { 2772 SVal V = CallOrMsg.getArgSVal(idx); 2773 2774 if (SymbolRef Sym = V.getAsLocSymbol()) { 2775 if (const RefVal *T = getRefBinding(state, Sym)) { 2776 state = updateSymbol(state, Sym, *T, Summ.getArg(idx), hasErr, C); 2777 if (hasErr) { 2778 ErrorRange = CallOrMsg.getArgSourceRange(idx); 2779 ErrorSym = Sym; 2780 break; 2781 } 2782 } 2783 } 2784 } 2785 2786 // Evaluate the effect on the message receiver. 2787 bool ReceiverIsTracked = false; 2788 if (!hasErr) { 2789 const ObjCMethodCall *MsgInvocation = dyn_cast<ObjCMethodCall>(&CallOrMsg); 2790 if (MsgInvocation) { 2791 if (SymbolRef Sym = MsgInvocation->getReceiverSVal().getAsLocSymbol()) { 2792 if (const RefVal *T = getRefBinding(state, Sym)) { 2793 ReceiverIsTracked = true; 2794 state = updateSymbol(state, Sym, *T, Summ.getReceiverEffect(), 2795 hasErr, C); 2796 if (hasErr) { 2797 ErrorRange = MsgInvocation->getOriginExpr()->getReceiverRange(); 2798 ErrorSym = Sym; 2799 } 2800 } 2801 } 2802 } 2803 } 2804 2805 // Process any errors. 2806 if (hasErr) { 2807 processNonLeakError(state, ErrorRange, hasErr, ErrorSym, C); 2808 return; 2809 } 2810 2811 // Consult the summary for the return value. 2812 RetEffect RE = Summ.getRetEffect(); 2813 2814 if (RE.getKind() == RetEffect::OwnedWhenTrackedReceiver) { 2815 if (ReceiverIsTracked) 2816 RE = getSummaryManager(C).getObjAllocRetEffect(); 2817 else 2818 RE = RetEffect::MakeNoRet(); 2819 } 2820 2821 switch (RE.getKind()) { 2822 default: 2823 llvm_unreachable("Unhandled RetEffect."); 2824 2825 case RetEffect::NoRet: 2826 case RetEffect::NoRetHard: 2827 // No work necessary. 2828 break; 2829 2830 case RetEffect::OwnedAllocatedSymbol: 2831 case RetEffect::OwnedSymbol: { 2832 SymbolRef Sym = CallOrMsg.getReturnValue().getAsSymbol(); 2833 if (!Sym) 2834 break; 2835 2836 // Use the result type from the CallEvent as it automatically adjusts 2837 // for methods/functions that return references. 2838 QualType ResultTy = CallOrMsg.getResultType(); 2839 state = setRefBinding(state, Sym, RefVal::makeOwned(RE.getObjKind(), 2840 ResultTy)); 2841 2842 // FIXME: Add a flag to the checker where allocations are assumed to 2843 // *not* fail. 2844 break; 2845 } 2846 2847 case RetEffect::GCNotOwnedSymbol: 2848 case RetEffect::ARCNotOwnedSymbol: 2849 case RetEffect::NotOwnedSymbol: { 2850 const Expr *Ex = CallOrMsg.getOriginExpr(); 2851 SymbolRef Sym = CallOrMsg.getReturnValue().getAsSymbol(); 2852 if (!Sym) 2853 break; 2854 assert(Ex); 2855 // Use GetReturnType in order to give [NSFoo alloc] the type NSFoo *. 2856 QualType ResultTy = GetReturnType(Ex, C.getASTContext()); 2857 state = setRefBinding(state, Sym, RefVal::makeNotOwned(RE.getObjKind(), 2858 ResultTy)); 2859 break; 2860 } 2861 } 2862 2863 // This check is actually necessary; otherwise the statement builder thinks 2864 // we've hit a previously-found path. 2865 // Normally addTransition takes care of this, but we want the node pointer. 2866 ExplodedNode *NewNode; 2867 if (state == C.getState()) { 2868 NewNode = C.getPredecessor(); 2869 } else { 2870 NewNode = C.addTransition(state); 2871 } 2872 2873 // Annotate the node with summary we used. 2874 if (NewNode) { 2875 // FIXME: This is ugly. See checkEndAnalysis for why it's necessary. 2876 if (ShouldResetSummaryLog) { 2877 SummaryLog.clear(); 2878 ShouldResetSummaryLog = false; 2879 } 2880 SummaryLog[NewNode] = &Summ; 2881 } 2882} 2883 2884 2885ProgramStateRef 2886RetainCountChecker::updateSymbol(ProgramStateRef state, SymbolRef sym, 2887 RefVal V, ArgEffect E, RefVal::Kind &hasErr, 2888 CheckerContext &C) const { 2889 // In GC mode [... release] and [... retain] do nothing. 2890 // In ARC mode they shouldn't exist at all, but we just ignore them. 2891 bool IgnoreRetainMsg = C.isObjCGCEnabled(); 2892 if (!IgnoreRetainMsg) 2893 IgnoreRetainMsg = (bool)C.getASTContext().getLangOpts().ObjCAutoRefCount; 2894 2895 switch (E) { 2896 default: 2897 break; 2898 case IncRefMsg: 2899 E = IgnoreRetainMsg ? DoNothing : IncRef; 2900 break; 2901 case DecRefMsg: 2902 E = IgnoreRetainMsg ? DoNothing : DecRef; 2903 break; 2904 case DecRefMsgAndStopTrackingHard: 2905 E = IgnoreRetainMsg ? StopTracking : DecRefAndStopTrackingHard; 2906 break; 2907 case MakeCollectable: 2908 E = C.isObjCGCEnabled() ? DecRef : DoNothing; 2909 break; 2910 } 2911 2912 // Handle all use-after-releases. 2913 if (!C.isObjCGCEnabled() && V.getKind() == RefVal::Released) { 2914 V = V ^ RefVal::ErrorUseAfterRelease; 2915 hasErr = V.getKind(); 2916 return setRefBinding(state, sym, V); 2917 } 2918 2919 switch (E) { 2920 case DecRefMsg: 2921 case IncRefMsg: 2922 case MakeCollectable: 2923 case DecRefMsgAndStopTrackingHard: 2924 llvm_unreachable("DecRefMsg/IncRefMsg/MakeCollectable already converted"); 2925 2926 case Dealloc: 2927 // Any use of -dealloc in GC is *bad*. 2928 if (C.isObjCGCEnabled()) { 2929 V = V ^ RefVal::ErrorDeallocGC; 2930 hasErr = V.getKind(); 2931 break; 2932 } 2933 2934 switch (V.getKind()) { 2935 default: 2936 llvm_unreachable("Invalid RefVal state for an explicit dealloc."); 2937 case RefVal::Owned: 2938 // The object immediately transitions to the released state. 2939 V = V ^ RefVal::Released; 2940 V.clearCounts(); 2941 return setRefBinding(state, sym, V); 2942 case RefVal::NotOwned: 2943 V = V ^ RefVal::ErrorDeallocNotOwned; 2944 hasErr = V.getKind(); 2945 break; 2946 } 2947 break; 2948 2949 case MayEscape: 2950 if (V.getKind() == RefVal::Owned) { 2951 V = V ^ RefVal::NotOwned; 2952 break; 2953 } 2954 2955 // Fall-through. 2956 2957 case DoNothing: 2958 return state; 2959 2960 case Autorelease: 2961 if (C.isObjCGCEnabled()) 2962 return state; 2963 // Update the autorelease counts. 2964 V = V.autorelease(); 2965 break; 2966 2967 case StopTracking: 2968 case StopTrackingHard: 2969 return removeRefBinding(state, sym); 2970 2971 case IncRef: 2972 switch (V.getKind()) { 2973 default: 2974 llvm_unreachable("Invalid RefVal state for a retain."); 2975 case RefVal::Owned: 2976 case RefVal::NotOwned: 2977 V = V + 1; 2978 break; 2979 case RefVal::Released: 2980 // Non-GC cases are handled above. 2981 assert(C.isObjCGCEnabled()); 2982 V = (V ^ RefVal::Owned) + 1; 2983 break; 2984 } 2985 break; 2986 2987 case DecRef: 2988 case DecRefBridgedTransfered: 2989 case DecRefAndStopTrackingHard: 2990 switch (V.getKind()) { 2991 default: 2992 // case 'RefVal::Released' handled above. 2993 llvm_unreachable("Invalid RefVal state for a release."); 2994 2995 case RefVal::Owned: 2996 assert(V.getCount() > 0); 2997 if (V.getCount() == 1) 2998 V = V ^ (E == DecRefBridgedTransfered ? 2999 RefVal::NotOwned : RefVal::Released); 3000 else if (E == DecRefAndStopTrackingHard) 3001 return removeRefBinding(state, sym); 3002 3003 V = V - 1; 3004 break; 3005 3006 case RefVal::NotOwned: 3007 if (V.getCount() > 0) { 3008 if (E == DecRefAndStopTrackingHard) 3009 return removeRefBinding(state, sym); 3010 V = V - 1; 3011 } else { 3012 V = V ^ RefVal::ErrorReleaseNotOwned; 3013 hasErr = V.getKind(); 3014 } 3015 break; 3016 3017 case RefVal::Released: 3018 // Non-GC cases are handled above. 3019 assert(C.isObjCGCEnabled()); 3020 V = V ^ RefVal::ErrorUseAfterRelease; 3021 hasErr = V.getKind(); 3022 break; 3023 } 3024 break; 3025 } 3026 return setRefBinding(state, sym, V); 3027} 3028 3029void RetainCountChecker::processNonLeakError(ProgramStateRef St, 3030 SourceRange ErrorRange, 3031 RefVal::Kind ErrorKind, 3032 SymbolRef Sym, 3033 CheckerContext &C) const { 3034 ExplodedNode *N = C.generateSink(St); 3035 if (!N) 3036 return; 3037 3038 CFRefBug *BT; 3039 switch (ErrorKind) { 3040 default: 3041 llvm_unreachable("Unhandled error."); 3042 case RefVal::ErrorUseAfterRelease: 3043 if (!useAfterRelease) 3044 useAfterRelease.reset(new UseAfterRelease()); 3045 BT = &*useAfterRelease; 3046 break; 3047 case RefVal::ErrorReleaseNotOwned: 3048 if (!releaseNotOwned) 3049 releaseNotOwned.reset(new BadRelease()); 3050 BT = &*releaseNotOwned; 3051 break; 3052 case RefVal::ErrorDeallocGC: 3053 if (!deallocGC) 3054 deallocGC.reset(new DeallocGC()); 3055 BT = &*deallocGC; 3056 break; 3057 case RefVal::ErrorDeallocNotOwned: 3058 if (!deallocNotOwned) 3059 deallocNotOwned.reset(new DeallocNotOwned()); 3060 BT = &*deallocNotOwned; 3061 break; 3062 } 3063 3064 assert(BT); 3065 CFRefReport *report = new CFRefReport(*BT, C.getASTContext().getLangOpts(), 3066 C.isObjCGCEnabled(), SummaryLog, 3067 N, Sym); 3068 report->addRange(ErrorRange); 3069 C.emitReport(report); 3070} 3071 3072//===----------------------------------------------------------------------===// 3073// Handle the return values of retain-count-related functions. 3074//===----------------------------------------------------------------------===// 3075 3076bool RetainCountChecker::evalCall(const CallExpr *CE, CheckerContext &C) const { 3077 // Get the callee. We're only interested in simple C functions. 3078 ProgramStateRef state = C.getState(); 3079 const FunctionDecl *FD = C.getCalleeDecl(CE); 3080 if (!FD) 3081 return false; 3082 3083 IdentifierInfo *II = FD->getIdentifier(); 3084 if (!II) 3085 return false; 3086 3087 // For now, we're only handling the functions that return aliases of their 3088 // arguments: CFRetain and CFMakeCollectable (and their families). 3089 // Eventually we should add other functions we can model entirely, 3090 // such as CFRelease, which don't invalidate their arguments or globals. 3091 if (CE->getNumArgs() != 1) 3092 return false; 3093 3094 // Get the name of the function. 3095 StringRef FName = II->getName(); 3096 FName = FName.substr(FName.find_first_not_of('_')); 3097 3098 // See if it's one of the specific functions we know how to eval. 3099 bool canEval = false; 3100 3101 QualType ResultTy = CE->getCallReturnType(); 3102 if (ResultTy->isObjCIdType()) { 3103 // Handle: id NSMakeCollectable(CFTypeRef) 3104 canEval = II->isStr("NSMakeCollectable"); 3105 } else if (ResultTy->isPointerType()) { 3106 // Handle: (CF|CG)Retain 3107 // CFMakeCollectable 3108 // It's okay to be a little sloppy here (CGMakeCollectable doesn't exist). 3109 if (cocoa::isRefType(ResultTy, "CF", FName) || 3110 cocoa::isRefType(ResultTy, "CG", FName)) { 3111 canEval = isRetain(FD, FName) || isMakeCollectable(FD, FName); 3112 } 3113 } 3114 3115 if (!canEval) 3116 return false; 3117 3118 // Bind the return value. 3119 const LocationContext *LCtx = C.getLocationContext(); 3120 SVal RetVal = state->getSVal(CE->getArg(0), LCtx); 3121 if (RetVal.isUnknown()) { 3122 // If the receiver is unknown, conjure a return value. 3123 SValBuilder &SVB = C.getSValBuilder(); 3124 RetVal = SVB.conjureSymbolVal(0, CE, LCtx, ResultTy, C.blockCount()); 3125 } 3126 state = state->BindExpr(CE, LCtx, RetVal, false); 3127 3128 // FIXME: This should not be necessary, but otherwise the argument seems to be 3129 // considered alive during the next statement. 3130 if (const MemRegion *ArgRegion = RetVal.getAsRegion()) { 3131 // Save the refcount status of the argument. 3132 SymbolRef Sym = RetVal.getAsLocSymbol(); 3133 const RefVal *Binding = 0; 3134 if (Sym) 3135 Binding = getRefBinding(state, Sym); 3136 3137 // Invalidate the argument region. 3138 state = state->invalidateRegions(ArgRegion, CE, C.blockCount(), LCtx, 3139 /*CausesPointerEscape*/ false); 3140 3141 // Restore the refcount status of the argument. 3142 if (Binding) 3143 state = setRefBinding(state, Sym, *Binding); 3144 } 3145 3146 C.addTransition(state); 3147 return true; 3148} 3149 3150//===----------------------------------------------------------------------===// 3151// Handle return statements. 3152//===----------------------------------------------------------------------===// 3153 3154void RetainCountChecker::checkPreStmt(const ReturnStmt *S, 3155 CheckerContext &C) const { 3156 3157 // Only adjust the reference count if this is the top-level call frame, 3158 // and not the result of inlining. In the future, we should do 3159 // better checking even for inlined calls, and see if they match 3160 // with their expected semantics (e.g., the method should return a retained 3161 // object, etc.). 3162 if (!C.inTopFrame()) 3163 return; 3164 3165 const Expr *RetE = S->getRetValue(); 3166 if (!RetE) 3167 return; 3168 3169 ProgramStateRef state = C.getState(); 3170 SymbolRef Sym = 3171 state->getSValAsScalarOrLoc(RetE, C.getLocationContext()).getAsLocSymbol(); 3172 if (!Sym) 3173 return; 3174 3175 // Get the reference count binding (if any). 3176 const RefVal *T = getRefBinding(state, Sym); 3177 if (!T) 3178 return; 3179 3180 // Change the reference count. 3181 RefVal X = *T; 3182 3183 switch (X.getKind()) { 3184 case RefVal::Owned: { 3185 unsigned cnt = X.getCount(); 3186 assert(cnt > 0); 3187 X.setCount(cnt - 1); 3188 X = X ^ RefVal::ReturnedOwned; 3189 break; 3190 } 3191 3192 case RefVal::NotOwned: { 3193 unsigned cnt = X.getCount(); 3194 if (cnt) { 3195 X.setCount(cnt - 1); 3196 X = X ^ RefVal::ReturnedOwned; 3197 } 3198 else { 3199 X = X ^ RefVal::ReturnedNotOwned; 3200 } 3201 break; 3202 } 3203 3204 default: 3205 return; 3206 } 3207 3208 // Update the binding. 3209 state = setRefBinding(state, Sym, X); 3210 ExplodedNode *Pred = C.addTransition(state); 3211 3212 // At this point we have updated the state properly. 3213 // Everything after this is merely checking to see if the return value has 3214 // been over- or under-retained. 3215 3216 // Did we cache out? 3217 if (!Pred) 3218 return; 3219 3220 // Update the autorelease counts. 3221 static SimpleProgramPointTag 3222 AutoreleaseTag("RetainCountChecker : Autorelease"); 3223 state = handleAutoreleaseCounts(state, Pred, &AutoreleaseTag, C, Sym, X); 3224 3225 // Did we cache out? 3226 if (!state) 3227 return; 3228 3229 // Get the updated binding. 3230 T = getRefBinding(state, Sym); 3231 assert(T); 3232 X = *T; 3233 3234 // Consult the summary of the enclosing method. 3235 RetainSummaryManager &Summaries = getSummaryManager(C); 3236 const Decl *CD = &Pred->getCodeDecl(); 3237 RetEffect RE = RetEffect::MakeNoRet(); 3238 3239 // FIXME: What is the convention for blocks? Is there one? 3240 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(CD)) { 3241 const RetainSummary *Summ = Summaries.getMethodSummary(MD); 3242 RE = Summ->getRetEffect(); 3243 } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CD)) { 3244 if (!isa<CXXMethodDecl>(FD)) { 3245 const RetainSummary *Summ = Summaries.getFunctionSummary(FD); 3246 RE = Summ->getRetEffect(); 3247 } 3248 } 3249 3250 checkReturnWithRetEffect(S, C, Pred, RE, X, Sym, state); 3251} 3252 3253void RetainCountChecker::checkReturnWithRetEffect(const ReturnStmt *S, 3254 CheckerContext &C, 3255 ExplodedNode *Pred, 3256 RetEffect RE, RefVal X, 3257 SymbolRef Sym, 3258 ProgramStateRef state) const { 3259 // Any leaks or other errors? 3260 if (X.isReturnedOwned() && X.getCount() == 0) { 3261 if (RE.getKind() != RetEffect::NoRet) { 3262 bool hasError = false; 3263 if (C.isObjCGCEnabled() && RE.getObjKind() == RetEffect::ObjC) { 3264 // Things are more complicated with garbage collection. If the 3265 // returned object is suppose to be an Objective-C object, we have 3266 // a leak (as the caller expects a GC'ed object) because no 3267 // method should return ownership unless it returns a CF object. 3268 hasError = true; 3269 X = X ^ RefVal::ErrorGCLeakReturned; 3270 } 3271 else if (!RE.isOwned()) { 3272 // Either we are using GC and the returned object is a CF type 3273 // or we aren't using GC. In either case, we expect that the 3274 // enclosing method is expected to return ownership. 3275 hasError = true; 3276 X = X ^ RefVal::ErrorLeakReturned; 3277 } 3278 3279 if (hasError) { 3280 // Generate an error node. 3281 state = setRefBinding(state, Sym, X); 3282 3283 static SimpleProgramPointTag 3284 ReturnOwnLeakTag("RetainCountChecker : ReturnsOwnLeak"); 3285 ExplodedNode *N = C.addTransition(state, Pred, &ReturnOwnLeakTag); 3286 if (N) { 3287 const LangOptions &LOpts = C.getASTContext().getLangOpts(); 3288 bool GCEnabled = C.isObjCGCEnabled(); 3289 CFRefReport *report = 3290 new CFRefLeakReport(*getLeakAtReturnBug(LOpts, GCEnabled), 3291 LOpts, GCEnabled, SummaryLog, 3292 N, Sym, C, IncludeAllocationLine); 3293 3294 C.emitReport(report); 3295 } 3296 } 3297 } 3298 } else if (X.isReturnedNotOwned()) { 3299 if (RE.isOwned()) { 3300 // Trying to return a not owned object to a caller expecting an 3301 // owned object. 3302 state = setRefBinding(state, Sym, X ^ RefVal::ErrorReturnedNotOwned); 3303 3304 static SimpleProgramPointTag 3305 ReturnNotOwnedTag("RetainCountChecker : ReturnNotOwnedForOwned"); 3306 ExplodedNode *N = C.addTransition(state, Pred, &ReturnNotOwnedTag); 3307 if (N) { 3308 if (!returnNotOwnedForOwned) 3309 returnNotOwnedForOwned.reset(new ReturnedNotOwnedForOwned()); 3310 3311 CFRefReport *report = 3312 new CFRefReport(*returnNotOwnedForOwned, 3313 C.getASTContext().getLangOpts(), 3314 C.isObjCGCEnabled(), SummaryLog, N, Sym); 3315 C.emitReport(report); 3316 } 3317 } 3318 } 3319} 3320 3321//===----------------------------------------------------------------------===// 3322// Check various ways a symbol can be invalidated. 3323//===----------------------------------------------------------------------===// 3324 3325void RetainCountChecker::checkBind(SVal loc, SVal val, const Stmt *S, 3326 CheckerContext &C) const { 3327 // Are we storing to something that causes the value to "escape"? 3328 bool escapes = true; 3329 3330 // A value escapes in three possible cases (this may change): 3331 // 3332 // (1) we are binding to something that is not a memory region. 3333 // (2) we are binding to a memregion that does not have stack storage 3334 // (3) we are binding to a memregion with stack storage that the store 3335 // does not understand. 3336 ProgramStateRef state = C.getState(); 3337 3338 if (Optional<loc::MemRegionVal> regionLoc = loc.getAs<loc::MemRegionVal>()) { 3339 escapes = !regionLoc->getRegion()->hasStackStorage(); 3340 3341 if (!escapes) { 3342 // To test (3), generate a new state with the binding added. If it is 3343 // the same state, then it escapes (since the store cannot represent 3344 // the binding). 3345 // Do this only if we know that the store is not supposed to generate the 3346 // same state. 3347 SVal StoredVal = state->getSVal(regionLoc->getRegion()); 3348 if (StoredVal != val) 3349 escapes = (state == (state->bindLoc(*regionLoc, val))); 3350 } 3351 if (!escapes) { 3352 // Case 4: We do not currently model what happens when a symbol is 3353 // assigned to a struct field, so be conservative here and let the symbol 3354 // go. TODO: This could definitely be improved upon. 3355 escapes = !isa<VarRegion>(regionLoc->getRegion()); 3356 } 3357 } 3358 3359 // If we are storing the value into an auto function scope variable annotated 3360 // with (__attribute__((cleanup))), stop tracking the value to avoid leak 3361 // false positives. 3362 if (const VarRegion *LVR = dyn_cast_or_null<VarRegion>(loc.getAsRegion())) { 3363 const VarDecl *VD = LVR->getDecl(); 3364 if (VD->getAttr<CleanupAttr>()) { 3365 escapes = true; 3366 } 3367 } 3368 3369 // If our store can represent the binding and we aren't storing to something 3370 // that doesn't have local storage then just return and have the simulation 3371 // state continue as is. 3372 if (!escapes) 3373 return; 3374 3375 // Otherwise, find all symbols referenced by 'val' that we are tracking 3376 // and stop tracking them. 3377 state = state->scanReachableSymbols<StopTrackingCallback>(val).getState(); 3378 C.addTransition(state); 3379} 3380 3381ProgramStateRef RetainCountChecker::evalAssume(ProgramStateRef state, 3382 SVal Cond, 3383 bool Assumption) const { 3384 3385 // FIXME: We may add to the interface of evalAssume the list of symbols 3386 // whose assumptions have changed. For now we just iterate through the 3387 // bindings and check if any of the tracked symbols are NULL. This isn't 3388 // too bad since the number of symbols we will track in practice are 3389 // probably small and evalAssume is only called at branches and a few 3390 // other places. 3391 RefBindingsTy B = state->get<RefBindings>(); 3392 3393 if (B.isEmpty()) 3394 return state; 3395 3396 bool changed = false; 3397 RefBindingsTy::Factory &RefBFactory = state->get_context<RefBindings>(); 3398 3399 for (RefBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I) { 3400 // Check if the symbol is null stop tracking the symbol. 3401 ConstraintManager &CMgr = state->getConstraintManager(); 3402 ConditionTruthVal AllocFailed = CMgr.isNull(state, I.getKey()); 3403 if (AllocFailed.isConstrainedTrue()) { 3404 changed = true; 3405 B = RefBFactory.remove(B, I.getKey()); 3406 } 3407 } 3408 3409 if (changed) 3410 state = state->set<RefBindings>(B); 3411 3412 return state; 3413} 3414 3415ProgramStateRef 3416RetainCountChecker::checkRegionChanges(ProgramStateRef state, 3417 const InvalidatedSymbols *invalidated, 3418 ArrayRef<const MemRegion *> ExplicitRegions, 3419 ArrayRef<const MemRegion *> Regions, 3420 const CallEvent *Call) const { 3421 if (!invalidated) 3422 return state; 3423 3424 llvm::SmallPtrSet<SymbolRef, 8> WhitelistedSymbols; 3425 for (ArrayRef<const MemRegion *>::iterator I = ExplicitRegions.begin(), 3426 E = ExplicitRegions.end(); I != E; ++I) { 3427 if (const SymbolicRegion *SR = (*I)->StripCasts()->getAs<SymbolicRegion>()) 3428 WhitelistedSymbols.insert(SR->getSymbol()); 3429 } 3430 3431 for (InvalidatedSymbols::const_iterator I=invalidated->begin(), 3432 E = invalidated->end(); I!=E; ++I) { 3433 SymbolRef sym = *I; 3434 if (WhitelistedSymbols.count(sym)) 3435 continue; 3436 // Remove any existing reference-count binding. 3437 state = removeRefBinding(state, sym); 3438 } 3439 return state; 3440} 3441 3442//===----------------------------------------------------------------------===// 3443// Handle dead symbols and end-of-path. 3444//===----------------------------------------------------------------------===// 3445 3446ProgramStateRef 3447RetainCountChecker::handleAutoreleaseCounts(ProgramStateRef state, 3448 ExplodedNode *Pred, 3449 const ProgramPointTag *Tag, 3450 CheckerContext &Ctx, 3451 SymbolRef Sym, RefVal V) const { 3452 unsigned ACnt = V.getAutoreleaseCount(); 3453 3454 // No autorelease counts? Nothing to be done. 3455 if (!ACnt) 3456 return state; 3457 3458 assert(!Ctx.isObjCGCEnabled() && "Autorelease counts in GC mode?"); 3459 unsigned Cnt = V.getCount(); 3460 3461 // FIXME: Handle sending 'autorelease' to already released object. 3462 3463 if (V.getKind() == RefVal::ReturnedOwned) 3464 ++Cnt; 3465 3466 if (ACnt <= Cnt) { 3467 if (ACnt == Cnt) { 3468 V.clearCounts(); 3469 if (V.getKind() == RefVal::ReturnedOwned) 3470 V = V ^ RefVal::ReturnedNotOwned; 3471 else 3472 V = V ^ RefVal::NotOwned; 3473 } else { 3474 V.setCount(V.getCount() - ACnt); 3475 V.setAutoreleaseCount(0); 3476 } 3477 return setRefBinding(state, Sym, V); 3478 } 3479 3480 // Woah! More autorelease counts then retain counts left. 3481 // Emit hard error. 3482 V = V ^ RefVal::ErrorOverAutorelease; 3483 state = setRefBinding(state, Sym, V); 3484 3485 ExplodedNode *N = Ctx.generateSink(state, Pred, Tag); 3486 if (N) { 3487 SmallString<128> sbuf; 3488 llvm::raw_svector_ostream os(sbuf); 3489 os << "Object was autoreleased "; 3490 if (V.getAutoreleaseCount() > 1) 3491 os << V.getAutoreleaseCount() << " times but the object "; 3492 else 3493 os << "but "; 3494 os << "has a +" << V.getCount() << " retain count"; 3495 3496 if (!overAutorelease) 3497 overAutorelease.reset(new OverAutorelease()); 3498 3499 const LangOptions &LOpts = Ctx.getASTContext().getLangOpts(); 3500 CFRefReport *report = 3501 new CFRefReport(*overAutorelease, LOpts, /* GCEnabled = */ false, 3502 SummaryLog, N, Sym, os.str()); 3503 Ctx.emitReport(report); 3504 } 3505 3506 return 0; 3507} 3508 3509ProgramStateRef 3510RetainCountChecker::handleSymbolDeath(ProgramStateRef state, 3511 SymbolRef sid, RefVal V, 3512 SmallVectorImpl<SymbolRef> &Leaked) const { 3513 bool hasLeak = false; 3514 if (V.isOwned()) 3515 hasLeak = true; 3516 else if (V.isNotOwned() || V.isReturnedOwned()) 3517 hasLeak = (V.getCount() > 0); 3518 3519 if (!hasLeak) 3520 return removeRefBinding(state, sid); 3521 3522 Leaked.push_back(sid); 3523 return setRefBinding(state, sid, V ^ RefVal::ErrorLeak); 3524} 3525 3526ExplodedNode * 3527RetainCountChecker::processLeaks(ProgramStateRef state, 3528 SmallVectorImpl<SymbolRef> &Leaked, 3529 CheckerContext &Ctx, 3530 ExplodedNode *Pred) const { 3531 // Generate an intermediate node representing the leak point. 3532 ExplodedNode *N = Ctx.addTransition(state, Pred); 3533 3534 if (N) { 3535 for (SmallVectorImpl<SymbolRef>::iterator 3536 I = Leaked.begin(), E = Leaked.end(); I != E; ++I) { 3537 3538 const LangOptions &LOpts = Ctx.getASTContext().getLangOpts(); 3539 bool GCEnabled = Ctx.isObjCGCEnabled(); 3540 CFRefBug *BT = Pred ? getLeakWithinFunctionBug(LOpts, GCEnabled) 3541 : getLeakAtReturnBug(LOpts, GCEnabled); 3542 assert(BT && "BugType not initialized."); 3543 3544 CFRefLeakReport *report = new CFRefLeakReport(*BT, LOpts, GCEnabled, 3545 SummaryLog, N, *I, Ctx, 3546 IncludeAllocationLine); 3547 Ctx.emitReport(report); 3548 } 3549 } 3550 3551 return N; 3552} 3553 3554void RetainCountChecker::checkEndFunction(CheckerContext &Ctx) const { 3555 ProgramStateRef state = Ctx.getState(); 3556 RefBindingsTy B = state->get<RefBindings>(); 3557 ExplodedNode *Pred = Ctx.getPredecessor(); 3558 3559 // Don't process anything within synthesized bodies. 3560 const LocationContext *LCtx = Pred->getLocationContext(); 3561 if (LCtx->getAnalysisDeclContext()->isBodyAutosynthesized()) { 3562 assert(LCtx->getParent()); 3563 return; 3564 } 3565 3566 for (RefBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I) { 3567 state = handleAutoreleaseCounts(state, Pred, /*Tag=*/0, Ctx, 3568 I->first, I->second); 3569 if (!state) 3570 return; 3571 } 3572 3573 // If the current LocationContext has a parent, don't check for leaks. 3574 // We will do that later. 3575 // FIXME: we should instead check for imbalances of the retain/releases, 3576 // and suggest annotations. 3577 if (LCtx->getParent()) 3578 return; 3579 3580 B = state->get<RefBindings>(); 3581 SmallVector<SymbolRef, 10> Leaked; 3582 3583 for (RefBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I) 3584 state = handleSymbolDeath(state, I->first, I->second, Leaked); 3585 3586 processLeaks(state, Leaked, Ctx, Pred); 3587} 3588 3589const ProgramPointTag * 3590RetainCountChecker::getDeadSymbolTag(SymbolRef sym) const { 3591 const SimpleProgramPointTag *&tag = DeadSymbolTags[sym]; 3592 if (!tag) { 3593 SmallString<64> buf; 3594 llvm::raw_svector_ostream out(buf); 3595 out << "RetainCountChecker : Dead Symbol : "; 3596 sym->dumpToStream(out); 3597 tag = new SimpleProgramPointTag(out.str()); 3598 } 3599 return tag; 3600} 3601 3602void RetainCountChecker::checkDeadSymbols(SymbolReaper &SymReaper, 3603 CheckerContext &C) const { 3604 ExplodedNode *Pred = C.getPredecessor(); 3605 3606 ProgramStateRef state = C.getState(); 3607 RefBindingsTy B = state->get<RefBindings>(); 3608 SmallVector<SymbolRef, 10> Leaked; 3609 3610 // Update counts from autorelease pools 3611 for (SymbolReaper::dead_iterator I = SymReaper.dead_begin(), 3612 E = SymReaper.dead_end(); I != E; ++I) { 3613 SymbolRef Sym = *I; 3614 if (const RefVal *T = B.lookup(Sym)){ 3615 // Use the symbol as the tag. 3616 // FIXME: This might not be as unique as we would like. 3617 const ProgramPointTag *Tag = getDeadSymbolTag(Sym); 3618 state = handleAutoreleaseCounts(state, Pred, Tag, C, Sym, *T); 3619 if (!state) 3620 return; 3621 3622 // Fetch the new reference count from the state, and use it to handle 3623 // this symbol. 3624 state = handleSymbolDeath(state, *I, *getRefBinding(state, Sym), Leaked); 3625 } 3626 } 3627 3628 if (Leaked.empty()) { 3629 C.addTransition(state); 3630 return; 3631 } 3632 3633 Pred = processLeaks(state, Leaked, C, Pred); 3634 3635 // Did we cache out? 3636 if (!Pred) 3637 return; 3638 3639 // Now generate a new node that nukes the old bindings. 3640 // The only bindings left at this point are the leaked symbols. 3641 RefBindingsTy::Factory &F = state->get_context<RefBindings>(); 3642 B = state->get<RefBindings>(); 3643 3644 for (SmallVectorImpl<SymbolRef>::iterator I = Leaked.begin(), 3645 E = Leaked.end(); 3646 I != E; ++I) 3647 B = F.remove(B, *I); 3648 3649 state = state->set<RefBindings>(B); 3650 C.addTransition(state, Pred); 3651} 3652 3653void RetainCountChecker::printState(raw_ostream &Out, ProgramStateRef State, 3654 const char *NL, const char *Sep) const { 3655 3656 RefBindingsTy B = State->get<RefBindings>(); 3657 3658 if (B.isEmpty()) 3659 return; 3660 3661 Out << Sep << NL; 3662 3663 for (RefBindingsTy::iterator I = B.begin(), E = B.end(); I != E; ++I) { 3664 Out << I->first << " : "; 3665 I->second.print(Out); 3666 Out << NL; 3667 } 3668} 3669 3670//===----------------------------------------------------------------------===// 3671// Checker registration. 3672//===----------------------------------------------------------------------===// 3673 3674void ento::registerRetainCountChecker(CheckerManager &Mgr) { 3675 Mgr.registerChecker<RetainCountChecker>(Mgr.getAnalyzerOptions()); 3676} 3677 3678//===----------------------------------------------------------------------===// 3679// Implementation of the CallEffects API. 3680//===----------------------------------------------------------------------===// 3681 3682namespace clang { namespace ento { namespace objc_retain { 3683 3684// This is a bit gross, but it allows us to populate CallEffects without 3685// creating a bunch of accessors. This kind is very localized, so the 3686// damage of this macro is limited. 3687#define createCallEffect(D, KIND)\ 3688 ASTContext &Ctx = D->getASTContext();\ 3689 LangOptions L = Ctx.getLangOpts();\ 3690 RetainSummaryManager M(Ctx, L.GCOnly, L.ObjCAutoRefCount);\ 3691 const RetainSummary *S = M.get ## KIND ## Summary(D);\ 3692 CallEffects CE(S->getRetEffect());\ 3693 CE.Receiver = S->getReceiverEffect();\ 3694 unsigned N = D->param_size();\ 3695 for (unsigned i = 0; i < N; ++i) {\ 3696 CE.Args.push_back(S->getArg(i));\ 3697 } 3698 3699CallEffects CallEffects::getEffect(const ObjCMethodDecl *MD) { 3700 createCallEffect(MD, Method); 3701 return CE; 3702} 3703 3704CallEffects CallEffects::getEffect(const FunctionDecl *FD) { 3705 createCallEffect(FD, Function); 3706 return CE; 3707} 3708 3709#undef createCallEffect 3710 3711}}} 3712