RetainCountChecker.cpp revision e921b1a8b6b6f47abbc9b3de47cc74a34db2852b
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/DeclObjC.h" 17#include "clang/AST/DeclCXX.h" 18#include "clang/Basic/LangOptions.h" 19#include "clang/Basic/SourceManager.h" 20#include "clang/Analysis/DomainSpecific/CocoaConventions.h" 21#include "clang/AST/ParentMap.h" 22#include "clang/StaticAnalyzer/Core/Checker.h" 23#include "clang/StaticAnalyzer/Core/CheckerManager.h" 24#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" 25#include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h" 26#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" 27#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h" 28#include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h" 29#include "clang/StaticAnalyzer/Core/PathSensitive/ObjCMessage.h" 30#include "llvm/ADT/DenseMap.h" 31#include "llvm/ADT/FoldingSet.h" 32#include "llvm/ADT/ImmutableList.h" 33#include "llvm/ADT/ImmutableMap.h" 34#include "llvm/ADT/SmallString.h" 35#include "llvm/ADT/STLExtras.h" 36#include "llvm/ADT/StringExtras.h" 37#include <cstdarg> 38 39using namespace clang; 40using namespace ento; 41using llvm::StrInStrNoCase; 42 43namespace { 44/// Wrapper around different kinds of node builder, so that helper functions 45/// can have a common interface. 46class GenericNodeBuilderRefCount { 47 CheckerContext *C; 48 const ProgramPointTag *tag; 49public: 50 GenericNodeBuilderRefCount(CheckerContext &c, 51 const ProgramPointTag *t = 0) 52 : C(&c), tag(t){} 53 54 ExplodedNode *MakeNode(ProgramStateRef state, ExplodedNode *Pred, 55 bool MarkAsSink = false) { 56 return C->addTransition(state, Pred, tag, MarkAsSink); 57 } 58}; 59} // end anonymous namespace 60 61//===----------------------------------------------------------------------===// 62// Primitives used for constructing summaries for function/method calls. 63//===----------------------------------------------------------------------===// 64 65/// ArgEffect is used to summarize a function/method call's effect on a 66/// particular argument. 67enum ArgEffect { DoNothing, Autorelease, Dealloc, DecRef, DecRefMsg, 68 DecRefBridgedTransfered, 69 IncRefMsg, IncRef, MakeCollectable, MayEscape, 70 NewAutoreleasePool, SelfOwn, StopTracking }; 71 72namespace llvm { 73template <> struct FoldingSetTrait<ArgEffect> { 74static inline void Profile(const ArgEffect X, FoldingSetNodeID& ID) { 75 ID.AddInteger((unsigned) X); 76} 77}; 78} // end llvm namespace 79 80/// ArgEffects summarizes the effects of a function/method call on all of 81/// its arguments. 82typedef llvm::ImmutableMap<unsigned,ArgEffect> ArgEffects; 83 84namespace { 85 86/// RetEffect is used to summarize a function/method call's behavior with 87/// respect to its return value. 88class RetEffect { 89public: 90 enum Kind { NoRet, OwnedSymbol, OwnedAllocatedSymbol, 91 NotOwnedSymbol, GCNotOwnedSymbol, ARCNotOwnedSymbol, 92 OwnedWhenTrackedReceiver }; 93 94 enum ObjKind { CF, ObjC, AnyObj }; 95 96private: 97 Kind K; 98 ObjKind O; 99 100 RetEffect(Kind k, ObjKind o = AnyObj) : K(k), O(o) {} 101 102public: 103 Kind getKind() const { return K; } 104 105 ObjKind getObjKind() const { return O; } 106 107 bool isOwned() const { 108 return K == OwnedSymbol || K == OwnedAllocatedSymbol || 109 K == OwnedWhenTrackedReceiver; 110 } 111 112 bool operator==(const RetEffect &Other) const { 113 return K == Other.K && O == Other.O; 114 } 115 116 static RetEffect MakeOwnedWhenTrackedReceiver() { 117 return RetEffect(OwnedWhenTrackedReceiver, ObjC); 118 } 119 120 static RetEffect MakeOwned(ObjKind o, bool isAllocated = false) { 121 return RetEffect(isAllocated ? OwnedAllocatedSymbol : OwnedSymbol, o); 122 } 123 static RetEffect MakeNotOwned(ObjKind o) { 124 return RetEffect(NotOwnedSymbol, o); 125 } 126 static RetEffect MakeGCNotOwned() { 127 return RetEffect(GCNotOwnedSymbol, ObjC); 128 } 129 static RetEffect MakeARCNotOwned() { 130 return RetEffect(ARCNotOwnedSymbol, ObjC); 131 } 132 static RetEffect MakeNoRet() { 133 return RetEffect(NoRet); 134 } 135}; 136 137//===----------------------------------------------------------------------===// 138// Reference-counting logic (typestate + counts). 139//===----------------------------------------------------------------------===// 140 141class RefVal { 142public: 143 enum Kind { 144 Owned = 0, // Owning reference. 145 NotOwned, // Reference is not owned by still valid (not freed). 146 Released, // Object has been released. 147 ReturnedOwned, // Returned object passes ownership to caller. 148 ReturnedNotOwned, // Return object does not pass ownership to caller. 149 ERROR_START, 150 ErrorDeallocNotOwned, // -dealloc called on non-owned object. 151 ErrorDeallocGC, // Calling -dealloc with GC enabled. 152 ErrorUseAfterRelease, // Object used after released. 153 ErrorReleaseNotOwned, // Release of an object that was not owned. 154 ERROR_LEAK_START, 155 ErrorLeak, // A memory leak due to excessive reference counts. 156 ErrorLeakReturned, // A memory leak due to the returning method not having 157 // the correct naming conventions. 158 ErrorGCLeakReturned, 159 ErrorOverAutorelease, 160 ErrorReturnedNotOwned 161 }; 162 163private: 164 Kind kind; 165 RetEffect::ObjKind okind; 166 unsigned Cnt; 167 unsigned ACnt; 168 QualType T; 169 170 RefVal(Kind k, RetEffect::ObjKind o, unsigned cnt, unsigned acnt, QualType t) 171 : kind(k), okind(o), Cnt(cnt), ACnt(acnt), T(t) {} 172 173public: 174 Kind getKind() const { return kind; } 175 176 RetEffect::ObjKind getObjKind() const { return okind; } 177 178 unsigned getCount() const { return Cnt; } 179 unsigned getAutoreleaseCount() const { return ACnt; } 180 unsigned getCombinedCounts() const { return Cnt + ACnt; } 181 void clearCounts() { Cnt = 0; ACnt = 0; } 182 void setCount(unsigned i) { Cnt = i; } 183 void setAutoreleaseCount(unsigned i) { ACnt = i; } 184 185 QualType getType() const { return T; } 186 187 bool isOwned() const { 188 return getKind() == Owned; 189 } 190 191 bool isNotOwned() const { 192 return getKind() == NotOwned; 193 } 194 195 bool isReturnedOwned() const { 196 return getKind() == ReturnedOwned; 197 } 198 199 bool isReturnedNotOwned() const { 200 return getKind() == ReturnedNotOwned; 201 } 202 203 static RefVal makeOwned(RetEffect::ObjKind o, QualType t, 204 unsigned Count = 1) { 205 return RefVal(Owned, o, Count, 0, t); 206 } 207 208 static RefVal makeNotOwned(RetEffect::ObjKind o, QualType t, 209 unsigned Count = 0) { 210 return RefVal(NotOwned, o, Count, 0, t); 211 } 212 213 // Comparison, profiling, and pretty-printing. 214 215 bool operator==(const RefVal& X) const { 216 return kind == X.kind && Cnt == X.Cnt && T == X.T && ACnt == X.ACnt; 217 } 218 219 RefVal operator-(size_t i) const { 220 return RefVal(getKind(), getObjKind(), getCount() - i, 221 getAutoreleaseCount(), getType()); 222 } 223 224 RefVal operator+(size_t i) const { 225 return RefVal(getKind(), getObjKind(), getCount() + i, 226 getAutoreleaseCount(), getType()); 227 } 228 229 RefVal operator^(Kind k) const { 230 return RefVal(k, getObjKind(), getCount(), getAutoreleaseCount(), 231 getType()); 232 } 233 234 RefVal autorelease() const { 235 return RefVal(getKind(), getObjKind(), getCount(), getAutoreleaseCount()+1, 236 getType()); 237 } 238 239 void Profile(llvm::FoldingSetNodeID& ID) const { 240 ID.AddInteger((unsigned) kind); 241 ID.AddInteger(Cnt); 242 ID.AddInteger(ACnt); 243 ID.Add(T); 244 } 245 246 void print(raw_ostream &Out) const; 247}; 248 249void RefVal::print(raw_ostream &Out) const { 250 if (!T.isNull()) 251 Out << "Tracked " << T.getAsString() << '/'; 252 253 switch (getKind()) { 254 default: llvm_unreachable("Invalid RefVal kind"); 255 case Owned: { 256 Out << "Owned"; 257 unsigned cnt = getCount(); 258 if (cnt) Out << " (+ " << cnt << ")"; 259 break; 260 } 261 262 case NotOwned: { 263 Out << "NotOwned"; 264 unsigned cnt = getCount(); 265 if (cnt) Out << " (+ " << cnt << ")"; 266 break; 267 } 268 269 case ReturnedOwned: { 270 Out << "ReturnedOwned"; 271 unsigned cnt = getCount(); 272 if (cnt) Out << " (+ " << cnt << ")"; 273 break; 274 } 275 276 case ReturnedNotOwned: { 277 Out << "ReturnedNotOwned"; 278 unsigned cnt = getCount(); 279 if (cnt) Out << " (+ " << cnt << ")"; 280 break; 281 } 282 283 case Released: 284 Out << "Released"; 285 break; 286 287 case ErrorDeallocGC: 288 Out << "-dealloc (GC)"; 289 break; 290 291 case ErrorDeallocNotOwned: 292 Out << "-dealloc (not-owned)"; 293 break; 294 295 case ErrorLeak: 296 Out << "Leaked"; 297 break; 298 299 case ErrorLeakReturned: 300 Out << "Leaked (Bad naming)"; 301 break; 302 303 case ErrorGCLeakReturned: 304 Out << "Leaked (GC-ed at return)"; 305 break; 306 307 case ErrorUseAfterRelease: 308 Out << "Use-After-Release [ERROR]"; 309 break; 310 311 case ErrorReleaseNotOwned: 312 Out << "Release of Not-Owned [ERROR]"; 313 break; 314 315 case RefVal::ErrorOverAutorelease: 316 Out << "Over autoreleased"; 317 break; 318 319 case RefVal::ErrorReturnedNotOwned: 320 Out << "Non-owned object returned instead of owned"; 321 break; 322 } 323 324 if (ACnt) { 325 Out << " [ARC +" << ACnt << ']'; 326 } 327} 328} //end anonymous namespace 329 330//===----------------------------------------------------------------------===// 331// RefBindings - State used to track object reference counts. 332//===----------------------------------------------------------------------===// 333 334typedef llvm::ImmutableMap<SymbolRef, RefVal> RefBindings; 335 336namespace clang { 337namespace ento { 338template<> 339struct ProgramStateTrait<RefBindings> 340 : public ProgramStatePartialTrait<RefBindings> { 341 static void *GDMIndex() { 342 static int RefBIndex = 0; 343 return &RefBIndex; 344 } 345}; 346} 347} 348 349//===----------------------------------------------------------------------===// 350// Function/Method behavior summaries. 351//===----------------------------------------------------------------------===// 352 353namespace { 354class RetainSummary { 355 /// Args - an ordered vector of (index, ArgEffect) pairs, where index 356 /// specifies the argument (starting from 0). This can be sparsely 357 /// populated; arguments with no entry in Args use 'DefaultArgEffect'. 358 ArgEffects Args; 359 360 /// DefaultArgEffect - The default ArgEffect to apply to arguments that 361 /// do not have an entry in Args. 362 ArgEffect DefaultArgEffect; 363 364 /// Receiver - If this summary applies to an Objective-C message expression, 365 /// this is the effect applied to the state of the receiver. 366 ArgEffect Receiver; 367 368 /// Ret - The effect on the return value. Used to indicate if the 369 /// function/method call returns a new tracked symbol. 370 RetEffect Ret; 371 372public: 373 RetainSummary(ArgEffects A, RetEffect R, ArgEffect defaultEff, 374 ArgEffect ReceiverEff) 375 : Args(A), DefaultArgEffect(defaultEff), Receiver(ReceiverEff), Ret(R) {} 376 377 /// getArg - Return the argument effect on the argument specified by 378 /// idx (starting from 0). 379 ArgEffect getArg(unsigned idx) const { 380 if (const ArgEffect *AE = Args.lookup(idx)) 381 return *AE; 382 383 return DefaultArgEffect; 384 } 385 386 void addArg(ArgEffects::Factory &af, unsigned idx, ArgEffect e) { 387 Args = af.add(Args, idx, e); 388 } 389 390 /// setDefaultArgEffect - Set the default argument effect. 391 void setDefaultArgEffect(ArgEffect E) { 392 DefaultArgEffect = E; 393 } 394 395 /// getRetEffect - Returns the effect on the return value of the call. 396 RetEffect getRetEffect() const { return Ret; } 397 398 /// setRetEffect - Set the effect of the return value of the call. 399 void setRetEffect(RetEffect E) { Ret = E; } 400 401 402 /// Sets the effect on the receiver of the message. 403 void setReceiverEffect(ArgEffect e) { Receiver = e; } 404 405 /// getReceiverEffect - Returns the effect on the receiver of the call. 406 /// This is only meaningful if the summary applies to an ObjCMessageExpr*. 407 ArgEffect getReceiverEffect() const { return Receiver; } 408 409 /// Test if two retain summaries are identical. Note that merely equivalent 410 /// summaries are not necessarily identical (for example, if an explicit 411 /// argument effect matches the default effect). 412 bool operator==(const RetainSummary &Other) const { 413 return Args == Other.Args && DefaultArgEffect == Other.DefaultArgEffect && 414 Receiver == Other.Receiver && Ret == Other.Ret; 415 } 416}; 417} // end anonymous namespace 418 419//===----------------------------------------------------------------------===// 420// Data structures for constructing summaries. 421//===----------------------------------------------------------------------===// 422 423namespace { 424class ObjCSummaryKey { 425 IdentifierInfo* II; 426 Selector S; 427public: 428 ObjCSummaryKey(IdentifierInfo* ii, Selector s) 429 : II(ii), S(s) {} 430 431 ObjCSummaryKey(const ObjCInterfaceDecl *d, Selector s) 432 : II(d ? d->getIdentifier() : 0), S(s) {} 433 434 ObjCSummaryKey(const ObjCInterfaceDecl *d, IdentifierInfo *ii, Selector s) 435 : II(d ? d->getIdentifier() : ii), S(s) {} 436 437 ObjCSummaryKey(Selector s) 438 : II(0), S(s) {} 439 440 IdentifierInfo *getIdentifier() const { return II; } 441 Selector getSelector() const { return S; } 442}; 443} 444 445namespace llvm { 446template <> struct DenseMapInfo<ObjCSummaryKey> { 447 static inline ObjCSummaryKey getEmptyKey() { 448 return ObjCSummaryKey(DenseMapInfo<IdentifierInfo*>::getEmptyKey(), 449 DenseMapInfo<Selector>::getEmptyKey()); 450 } 451 452 static inline ObjCSummaryKey getTombstoneKey() { 453 return ObjCSummaryKey(DenseMapInfo<IdentifierInfo*>::getTombstoneKey(), 454 DenseMapInfo<Selector>::getTombstoneKey()); 455 } 456 457 static unsigned getHashValue(const ObjCSummaryKey &V) { 458 return (DenseMapInfo<IdentifierInfo*>::getHashValue(V.getIdentifier()) 459 & 0x88888888) 460 | (DenseMapInfo<Selector>::getHashValue(V.getSelector()) 461 & 0x55555555); 462 } 463 464 static bool isEqual(const ObjCSummaryKey& LHS, const ObjCSummaryKey& RHS) { 465 return DenseMapInfo<IdentifierInfo*>::isEqual(LHS.getIdentifier(), 466 RHS.getIdentifier()) && 467 DenseMapInfo<Selector>::isEqual(LHS.getSelector(), 468 RHS.getSelector()); 469 } 470 471}; 472template <> 473struct isPodLike<ObjCSummaryKey> { static const bool value = true; }; 474} // end llvm namespace 475 476namespace { 477class ObjCSummaryCache { 478 typedef llvm::DenseMap<ObjCSummaryKey, const RetainSummary *> MapTy; 479 MapTy M; 480public: 481 ObjCSummaryCache() {} 482 483 const RetainSummary * find(const ObjCInterfaceDecl *D, IdentifierInfo *ClsName, 484 Selector S) { 485 // Lookup the method using the decl for the class @interface. If we 486 // have no decl, lookup using the class name. 487 return D ? find(D, S) : find(ClsName, S); 488 } 489 490 const RetainSummary * find(const ObjCInterfaceDecl *D, Selector S) { 491 // Do a lookup with the (D,S) pair. If we find a match return 492 // the iterator. 493 ObjCSummaryKey K(D, S); 494 MapTy::iterator I = M.find(K); 495 496 if (I != M.end() || !D) 497 return I->second; 498 499 // Walk the super chain. If we find a hit with a parent, we'll end 500 // up returning that summary. We actually allow that key (null,S), as 501 // we cache summaries for the null ObjCInterfaceDecl* to allow us to 502 // generate initial summaries without having to worry about NSObject 503 // being declared. 504 // FIXME: We may change this at some point. 505 for (ObjCInterfaceDecl *C=D->getSuperClass() ;; C=C->getSuperClass()) { 506 if ((I = M.find(ObjCSummaryKey(C, S))) != M.end()) 507 break; 508 509 if (!C) 510 return NULL; 511 } 512 513 // Cache the summary with original key to make the next lookup faster 514 // and return the iterator. 515 const RetainSummary *Summ = I->second; 516 M[K] = Summ; 517 return Summ; 518 } 519 520 const RetainSummary *find(IdentifierInfo* II, Selector S) { 521 // FIXME: Class method lookup. Right now we dont' have a good way 522 // of going between IdentifierInfo* and the class hierarchy. 523 MapTy::iterator I = M.find(ObjCSummaryKey(II, S)); 524 525 if (I == M.end()) 526 I = M.find(ObjCSummaryKey(S)); 527 528 return I == M.end() ? NULL : I->second; 529 } 530 531 const RetainSummary *& operator[](ObjCSummaryKey K) { 532 return M[K]; 533 } 534 535 const RetainSummary *& operator[](Selector S) { 536 return M[ ObjCSummaryKey(S) ]; 537 } 538}; 539} // end anonymous namespace 540 541//===----------------------------------------------------------------------===// 542// Data structures for managing collections of summaries. 543//===----------------------------------------------------------------------===// 544 545namespace { 546class RetainSummaryManager { 547 548 //==-----------------------------------------------------------------==// 549 // Typedefs. 550 //==-----------------------------------------------------------------==// 551 552 typedef llvm::DenseMap<const FunctionDecl*, const RetainSummary *> 553 FuncSummariesTy; 554 555 typedef ObjCSummaryCache ObjCMethodSummariesTy; 556 557 //==-----------------------------------------------------------------==// 558 // Data. 559 //==-----------------------------------------------------------------==// 560 561 /// Ctx - The ASTContext object for the analyzed ASTs. 562 ASTContext &Ctx; 563 564 /// GCEnabled - Records whether or not the analyzed code runs in GC mode. 565 const bool GCEnabled; 566 567 /// Records whether or not the analyzed code runs in ARC mode. 568 const bool ARCEnabled; 569 570 /// FuncSummaries - A map from FunctionDecls to summaries. 571 FuncSummariesTy FuncSummaries; 572 573 /// ObjCClassMethodSummaries - A map from selectors (for instance methods) 574 /// to summaries. 575 ObjCMethodSummariesTy ObjCClassMethodSummaries; 576 577 /// ObjCMethodSummaries - A map from selectors to summaries. 578 ObjCMethodSummariesTy ObjCMethodSummaries; 579 580 /// BPAlloc - A BumpPtrAllocator used for allocating summaries, ArgEffects, 581 /// and all other data used by the checker. 582 llvm::BumpPtrAllocator BPAlloc; 583 584 /// AF - A factory for ArgEffects objects. 585 ArgEffects::Factory AF; 586 587 /// ScratchArgs - A holding buffer for construct ArgEffects. 588 ArgEffects ScratchArgs; 589 590 /// ObjCAllocRetE - Default return effect for methods returning Objective-C 591 /// objects. 592 RetEffect ObjCAllocRetE; 593 594 /// ObjCInitRetE - Default return effect for init methods returning 595 /// Objective-C objects. 596 RetEffect ObjCInitRetE; 597 598 RetainSummary DefaultSummary; 599 const RetainSummary *StopSummary; 600 601 //==-----------------------------------------------------------------==// 602 // Methods. 603 //==-----------------------------------------------------------------==// 604 605 /// getArgEffects - Returns a persistent ArgEffects object based on the 606 /// data in ScratchArgs. 607 ArgEffects getArgEffects(); 608 609 enum UnaryFuncKind { cfretain, cfrelease, cfmakecollectable }; 610 611public: 612 RetEffect getObjAllocRetEffect() const { return ObjCAllocRetE; } 613 614 const RetainSummary *getDefaultSummary() { 615 return &DefaultSummary; 616 } 617 618 const RetainSummary *getUnarySummary(const FunctionType* FT, 619 UnaryFuncKind func); 620 621 const RetainSummary *getCFSummaryCreateRule(const FunctionDecl *FD); 622 const RetainSummary *getCFSummaryGetRule(const FunctionDecl *FD); 623 const RetainSummary *getCFCreateGetRuleSummary(const FunctionDecl *FD); 624 625 const RetainSummary *getPersistentSummary(ArgEffects AE, RetEffect RetEff, 626 ArgEffect ReceiverEff = DoNothing, 627 ArgEffect DefaultEff = MayEscape); 628 629 const RetainSummary *getPersistentSummary(RetEffect RE, 630 ArgEffect ReceiverEff = DoNothing, 631 ArgEffect DefaultEff = MayEscape) { 632 return getPersistentSummary(getArgEffects(), RE, ReceiverEff, DefaultEff); 633 } 634 635 const RetainSummary *getPersistentStopSummary() { 636 if (StopSummary) 637 return StopSummary; 638 639 StopSummary = getPersistentSummary(RetEffect::MakeNoRet(), 640 StopTracking, StopTracking); 641 642 return StopSummary; 643 } 644 645 void InitializeClassMethodSummaries(); 646 void InitializeMethodSummaries(); 647private: 648 void addNSObjectClsMethSummary(Selector S, const RetainSummary *Summ) { 649 ObjCClassMethodSummaries[S] = Summ; 650 } 651 652 void addNSObjectMethSummary(Selector S, const RetainSummary *Summ) { 653 ObjCMethodSummaries[S] = Summ; 654 } 655 656 void addClassMethSummary(const char* Cls, const char* name, 657 const RetainSummary *Summ, bool isNullary = true) { 658 IdentifierInfo* ClsII = &Ctx.Idents.get(Cls); 659 Selector S = isNullary ? GetNullarySelector(name, Ctx) 660 : GetUnarySelector(name, Ctx); 661 ObjCClassMethodSummaries[ObjCSummaryKey(ClsII, S)] = Summ; 662 } 663 664 void addInstMethSummary(const char* Cls, const char* nullaryName, 665 const RetainSummary *Summ) { 666 IdentifierInfo* ClsII = &Ctx.Idents.get(Cls); 667 Selector S = GetNullarySelector(nullaryName, Ctx); 668 ObjCMethodSummaries[ObjCSummaryKey(ClsII, S)] = Summ; 669 } 670 671 Selector generateSelector(va_list argp) { 672 SmallVector<IdentifierInfo*, 10> II; 673 674 while (const char* s = va_arg(argp, const char*)) 675 II.push_back(&Ctx.Idents.get(s)); 676 677 return Ctx.Selectors.getSelector(II.size(), &II[0]); 678 } 679 680 void addMethodSummary(IdentifierInfo *ClsII, ObjCMethodSummariesTy& Summaries, 681 const RetainSummary * Summ, va_list argp) { 682 Selector S = generateSelector(argp); 683 Summaries[ObjCSummaryKey(ClsII, S)] = Summ; 684 } 685 686 void addInstMethSummary(const char* Cls, const RetainSummary * Summ, ...) { 687 va_list argp; 688 va_start(argp, Summ); 689 addMethodSummary(&Ctx.Idents.get(Cls), ObjCMethodSummaries, Summ, argp); 690 va_end(argp); 691 } 692 693 void addClsMethSummary(const char* Cls, const RetainSummary * Summ, ...) { 694 va_list argp; 695 va_start(argp, Summ); 696 addMethodSummary(&Ctx.Idents.get(Cls),ObjCClassMethodSummaries, Summ, argp); 697 va_end(argp); 698 } 699 700 void addClsMethSummary(IdentifierInfo *II, const RetainSummary * Summ, ...) { 701 va_list argp; 702 va_start(argp, Summ); 703 addMethodSummary(II, ObjCClassMethodSummaries, Summ, argp); 704 va_end(argp); 705 } 706 707public: 708 709 RetainSummaryManager(ASTContext &ctx, bool gcenabled, bool usesARC) 710 : Ctx(ctx), 711 GCEnabled(gcenabled), 712 ARCEnabled(usesARC), 713 AF(BPAlloc), ScratchArgs(AF.getEmptyMap()), 714 ObjCAllocRetE(gcenabled 715 ? RetEffect::MakeGCNotOwned() 716 : (usesARC ? RetEffect::MakeARCNotOwned() 717 : RetEffect::MakeOwned(RetEffect::ObjC, true))), 718 ObjCInitRetE(gcenabled 719 ? RetEffect::MakeGCNotOwned() 720 : (usesARC ? RetEffect::MakeARCNotOwned() 721 : RetEffect::MakeOwnedWhenTrackedReceiver())), 722 DefaultSummary(AF.getEmptyMap() /* per-argument effects (none) */, 723 RetEffect::MakeNoRet() /* return effect */, 724 MayEscape, /* default argument effect */ 725 DoNothing /* receiver effect */), 726 StopSummary(0) { 727 728 InitializeClassMethodSummaries(); 729 InitializeMethodSummaries(); 730 } 731 732 const RetainSummary *getSummary(const FunctionDecl *FD); 733 734 const RetainSummary *getInstanceMethodSummary(const ObjCMessage &msg, 735 ProgramStateRef state, 736 const LocationContext *LC); 737 738 const RetainSummary *getInstanceMethodSummary(const ObjCMessage &msg, 739 const ObjCInterfaceDecl *ID) { 740 return getInstanceMethodSummary(msg.getSelector(), 0, 741 ID, msg.getMethodDecl(), msg.getType(Ctx)); 742 } 743 744 const RetainSummary *getInstanceMethodSummary(Selector S, 745 IdentifierInfo *ClsName, 746 const ObjCInterfaceDecl *ID, 747 const ObjCMethodDecl *MD, 748 QualType RetTy); 749 750 const RetainSummary *getClassMethodSummary(Selector S, 751 IdentifierInfo *ClsName, 752 const ObjCInterfaceDecl *ID, 753 const ObjCMethodDecl *MD, 754 QualType RetTy); 755 756 const RetainSummary *getClassMethodSummary(const ObjCMessage &msg) { 757 const ObjCInterfaceDecl *Class = 0; 758 if (!msg.isInstanceMessage()) 759 Class = msg.getReceiverInterface(); 760 761 return getClassMethodSummary(msg.getSelector(), 762 Class? Class->getIdentifier() : 0, 763 Class, 764 msg.getMethodDecl(), msg.getType(Ctx)); 765 } 766 767 /// getMethodSummary - This version of getMethodSummary is used to query 768 /// the summary for the current method being analyzed. 769 const RetainSummary *getMethodSummary(const ObjCMethodDecl *MD) { 770 // FIXME: Eventually this should be unneeded. 771 const ObjCInterfaceDecl *ID = MD->getClassInterface(); 772 Selector S = MD->getSelector(); 773 IdentifierInfo *ClsName = ID->getIdentifier(); 774 QualType ResultTy = MD->getResultType(); 775 776 if (MD->isInstanceMethod()) 777 return getInstanceMethodSummary(S, ClsName, ID, MD, ResultTy); 778 else 779 return getClassMethodSummary(S, ClsName, ID, MD, ResultTy); 780 } 781 782 const RetainSummary *getCommonMethodSummary(const ObjCMethodDecl *MD, 783 Selector S, QualType RetTy); 784 785 void updateSummaryFromAnnotations(const RetainSummary *&Summ, 786 const ObjCMethodDecl *MD); 787 788 void updateSummaryFromAnnotations(const RetainSummary *&Summ, 789 const FunctionDecl *FD); 790 791 bool isGCEnabled() const { return GCEnabled; } 792 793 bool isARCEnabled() const { return ARCEnabled; } 794 795 bool isARCorGCEnabled() const { return GCEnabled || ARCEnabled; } 796 797 const RetainSummary *copySummary(const RetainSummary *OldSumm) { 798 RetainSummary *Summ = (RetainSummary *) BPAlloc.Allocate<RetainSummary>(); 799 new (Summ) RetainSummary(*OldSumm); 800 return Summ; 801 } 802}; 803 804// Used to avoid allocating long-term (BPAlloc'd) memory for default retain 805// summaries. If a function or method looks like it has a default summary, but 806// it has annotations, the annotations are added to the stack-based template 807// and then copied into managed memory. 808class RetainSummaryTemplate { 809 RetainSummaryManager &Manager; 810 const RetainSummary *&RealSummary; 811 RetainSummary ScratchSummary; 812 bool Accessed; 813public: 814 RetainSummaryTemplate(const RetainSummary *&real, const RetainSummary &base, 815 RetainSummaryManager &mgr) 816 : Manager(mgr), RealSummary(real), ScratchSummary(real ? *real : base), 817 Accessed(false) {} 818 819 ~RetainSummaryTemplate() { 820 if (Accessed) 821 RealSummary = Manager.copySummary(&ScratchSummary); 822 } 823 824 RetainSummary &operator*() { 825 Accessed = true; 826 return ScratchSummary; 827 } 828 829 RetainSummary *operator->() { 830 Accessed = true; 831 return &ScratchSummary; 832 } 833}; 834 835} // end anonymous namespace 836 837//===----------------------------------------------------------------------===// 838// Implementation of checker data structures. 839//===----------------------------------------------------------------------===// 840 841ArgEffects RetainSummaryManager::getArgEffects() { 842 ArgEffects AE = ScratchArgs; 843 ScratchArgs = AF.getEmptyMap(); 844 return AE; 845} 846 847const RetainSummary * 848RetainSummaryManager::getPersistentSummary(ArgEffects AE, RetEffect RetEff, 849 ArgEffect ReceiverEff, 850 ArgEffect DefaultEff) { 851 // Create the summary and return it. 852 RetainSummary *Summ = (RetainSummary *) BPAlloc.Allocate<RetainSummary>(); 853 new (Summ) RetainSummary(AE, RetEff, DefaultEff, ReceiverEff); 854 return Summ; 855} 856 857//===----------------------------------------------------------------------===// 858// Summary creation for functions (largely uses of Core Foundation). 859//===----------------------------------------------------------------------===// 860 861static bool isRetain(const FunctionDecl *FD, StringRef FName) { 862 return FName.endswith("Retain"); 863} 864 865static bool isRelease(const FunctionDecl *FD, StringRef FName) { 866 return FName.endswith("Release"); 867} 868 869static bool isMakeCollectable(const FunctionDecl *FD, StringRef FName) { 870 // FIXME: Remove FunctionDecl parameter. 871 // FIXME: Is it really okay if MakeCollectable isn't a suffix? 872 return FName.find("MakeCollectable") != StringRef::npos; 873} 874 875const RetainSummary * RetainSummaryManager::getSummary(const FunctionDecl *FD) { 876 // Look up a summary in our cache of FunctionDecls -> Summaries. 877 FuncSummariesTy::iterator I = FuncSummaries.find(FD); 878 if (I != FuncSummaries.end()) 879 return I->second; 880 881 // No summary? Generate one. 882 const RetainSummary *S = 0; 883 884 do { 885 // We generate "stop" summaries for implicitly defined functions. 886 if (FD->isImplicit()) { 887 S = getPersistentStopSummary(); 888 break; 889 } 890 // For C++ methods, generate an implicit "stop" summary as well. We 891 // can relax this once we have a clear policy for C++ methods and 892 // ownership attributes. 893 if (isa<CXXMethodDecl>(FD)) { 894 S = getPersistentStopSummary(); 895 break; 896 } 897 898 // [PR 3337] Use 'getAs<FunctionType>' to strip away any typedefs on the 899 // function's type. 900 const FunctionType* FT = FD->getType()->getAs<FunctionType>(); 901 const IdentifierInfo *II = FD->getIdentifier(); 902 if (!II) 903 break; 904 905 StringRef FName = II->getName(); 906 907 // Strip away preceding '_'. Doing this here will effect all the checks 908 // down below. 909 FName = FName.substr(FName.find_first_not_of('_')); 910 911 // Inspect the result type. 912 QualType RetTy = FT->getResultType(); 913 914 // FIXME: This should all be refactored into a chain of "summary lookup" 915 // filters. 916 assert(ScratchArgs.isEmpty()); 917 918 if (FName == "pthread_create") { 919 // Part of: <rdar://problem/7299394>. This will be addressed 920 // better with IPA. 921 S = getPersistentStopSummary(); 922 } else if (FName == "NSMakeCollectable") { 923 // Handle: id NSMakeCollectable(CFTypeRef) 924 S = (RetTy->isObjCIdType()) 925 ? getUnarySummary(FT, cfmakecollectable) 926 : getPersistentStopSummary(); 927 } else if (FName == "IOBSDNameMatching" || 928 FName == "IOServiceMatching" || 929 FName == "IOServiceNameMatching" || 930 FName == "IORegistryEntryIDMatching" || 931 FName == "IOOpenFirmwarePathMatching") { 932 // Part of <rdar://problem/6961230>. (IOKit) 933 // This should be addressed using a API table. 934 S = getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true), 935 DoNothing, DoNothing); 936 } else if (FName == "IOServiceGetMatchingService" || 937 FName == "IOServiceGetMatchingServices") { 938 // FIXES: <rdar://problem/6326900> 939 // This should be addressed using a API table. This strcmp is also 940 // a little gross, but there is no need to super optimize here. 941 ScratchArgs = AF.add(ScratchArgs, 1, DecRef); 942 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 943 } else if (FName == "IOServiceAddNotification" || 944 FName == "IOServiceAddMatchingNotification") { 945 // Part of <rdar://problem/6961230>. (IOKit) 946 // This should be addressed using a API table. 947 ScratchArgs = AF.add(ScratchArgs, 2, DecRef); 948 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 949 } else if (FName == "CVPixelBufferCreateWithBytes") { 950 // FIXES: <rdar://problem/7283567> 951 // Eventually this can be improved by recognizing that the pixel 952 // buffer passed to CVPixelBufferCreateWithBytes is released via 953 // a callback and doing full IPA to make sure this is done correctly. 954 // FIXME: This function has an out parameter that returns an 955 // allocated object. 956 ScratchArgs = AF.add(ScratchArgs, 7, StopTracking); 957 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 958 } else if (FName == "CGBitmapContextCreateWithData") { 959 // FIXES: <rdar://problem/7358899> 960 // Eventually this can be improved by recognizing that 'releaseInfo' 961 // passed to CGBitmapContextCreateWithData is released via 962 // a callback and doing full IPA to make sure this is done correctly. 963 ScratchArgs = AF.add(ScratchArgs, 8, StopTracking); 964 S = getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true), 965 DoNothing, DoNothing); 966 } else if (FName == "CVPixelBufferCreateWithPlanarBytes") { 967 // FIXES: <rdar://problem/7283567> 968 // Eventually this can be improved by recognizing that the pixel 969 // buffer passed to CVPixelBufferCreateWithPlanarBytes is released 970 // via a callback and doing full IPA to make sure this is done 971 // correctly. 972 ScratchArgs = AF.add(ScratchArgs, 12, StopTracking); 973 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 974 } 975 976 // Did we get a summary? 977 if (S) 978 break; 979 980 // Enable this code once the semantics of NSDeallocateObject are resolved 981 // for GC. <rdar://problem/6619988> 982#if 0 983 // Handle: NSDeallocateObject(id anObject); 984 // This method does allow 'nil' (although we don't check it now). 985 if (strcmp(FName, "NSDeallocateObject") == 0) { 986 return RetTy == Ctx.VoidTy 987 ? getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, Dealloc) 988 : getPersistentStopSummary(); 989 } 990#endif 991 992 if (RetTy->isPointerType()) { 993 // For CoreFoundation ('CF') types. 994 if (cocoa::isRefType(RetTy, "CF", FName)) { 995 if (isRetain(FD, FName)) 996 S = getUnarySummary(FT, cfretain); 997 else if (isMakeCollectable(FD, FName)) 998 S = getUnarySummary(FT, cfmakecollectable); 999 else 1000 S = getCFCreateGetRuleSummary(FD); 1001 1002 break; 1003 } 1004 1005 // For CoreGraphics ('CG') types. 1006 if (cocoa::isRefType(RetTy, "CG", FName)) { 1007 if (isRetain(FD, FName)) 1008 S = getUnarySummary(FT, cfretain); 1009 else 1010 S = getCFCreateGetRuleSummary(FD); 1011 1012 break; 1013 } 1014 1015 // For the Disk Arbitration API (DiskArbitration/DADisk.h) 1016 if (cocoa::isRefType(RetTy, "DADisk") || 1017 cocoa::isRefType(RetTy, "DADissenter") || 1018 cocoa::isRefType(RetTy, "DASessionRef")) { 1019 S = getCFCreateGetRuleSummary(FD); 1020 break; 1021 } 1022 1023 break; 1024 } 1025 1026 // Check for release functions, the only kind of functions that we care 1027 // about that don't return a pointer type. 1028 if (FName[0] == 'C' && (FName[1] == 'F' || FName[1] == 'G')) { 1029 // Test for 'CGCF'. 1030 FName = FName.substr(FName.startswith("CGCF") ? 4 : 2); 1031 1032 if (isRelease(FD, FName)) 1033 S = getUnarySummary(FT, cfrelease); 1034 else { 1035 assert (ScratchArgs.isEmpty()); 1036 // Remaining CoreFoundation and CoreGraphics functions. 1037 // We use to assume that they all strictly followed the ownership idiom 1038 // and that ownership cannot be transferred. While this is technically 1039 // correct, many methods allow a tracked object to escape. For example: 1040 // 1041 // CFMutableDictionaryRef x = CFDictionaryCreateMutable(...); 1042 // CFDictionaryAddValue(y, key, x); 1043 // CFRelease(x); 1044 // ... it is okay to use 'x' since 'y' has a reference to it 1045 // 1046 // We handle this and similar cases with the follow heuristic. If the 1047 // function name contains "InsertValue", "SetValue", "AddValue", 1048 // "AppendValue", or "SetAttribute", then we assume that arguments may 1049 // "escape." This means that something else holds on to the object, 1050 // allowing it be used even after its local retain count drops to 0. 1051 ArgEffect E = (StrInStrNoCase(FName, "InsertValue") != StringRef::npos|| 1052 StrInStrNoCase(FName, "AddValue") != StringRef::npos || 1053 StrInStrNoCase(FName, "SetValue") != StringRef::npos || 1054 StrInStrNoCase(FName, "AppendValue") != StringRef::npos|| 1055 StrInStrNoCase(FName, "SetAttribute") != StringRef::npos) 1056 ? MayEscape : DoNothing; 1057 1058 S = getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, E); 1059 } 1060 } 1061 } 1062 while (0); 1063 1064 // Annotations override defaults. 1065 updateSummaryFromAnnotations(S, FD); 1066 1067 FuncSummaries[FD] = S; 1068 return S; 1069} 1070 1071const RetainSummary * 1072RetainSummaryManager::getCFCreateGetRuleSummary(const FunctionDecl *FD) { 1073 if (coreFoundation::followsCreateRule(FD)) 1074 return getCFSummaryCreateRule(FD); 1075 1076 return getCFSummaryGetRule(FD); 1077} 1078 1079const RetainSummary * 1080RetainSummaryManager::getUnarySummary(const FunctionType* FT, 1081 UnaryFuncKind func) { 1082 1083 // Sanity check that this is *really* a unary function. This can 1084 // happen if people do weird things. 1085 const FunctionProtoType* FTP = dyn_cast<FunctionProtoType>(FT); 1086 if (!FTP || FTP->getNumArgs() != 1) 1087 return getPersistentStopSummary(); 1088 1089 assert (ScratchArgs.isEmpty()); 1090 1091 ArgEffect Effect; 1092 switch (func) { 1093 case cfretain: Effect = IncRef; break; 1094 case cfrelease: Effect = DecRef; break; 1095 case cfmakecollectable: Effect = MakeCollectable; break; 1096 } 1097 1098 ScratchArgs = AF.add(ScratchArgs, 0, Effect); 1099 return getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, DoNothing); 1100} 1101 1102const RetainSummary * 1103RetainSummaryManager::getCFSummaryCreateRule(const FunctionDecl *FD) { 1104 assert (ScratchArgs.isEmpty()); 1105 1106 return getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true)); 1107} 1108 1109const RetainSummary * 1110RetainSummaryManager::getCFSummaryGetRule(const FunctionDecl *FD) { 1111 assert (ScratchArgs.isEmpty()); 1112 return getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::CF), 1113 DoNothing, DoNothing); 1114} 1115 1116//===----------------------------------------------------------------------===// 1117// Summary creation for Selectors. 1118//===----------------------------------------------------------------------===// 1119 1120void 1121RetainSummaryManager::updateSummaryFromAnnotations(const RetainSummary *&Summ, 1122 const FunctionDecl *FD) { 1123 if (!FD) 1124 return; 1125 1126 RetainSummaryTemplate Template(Summ, DefaultSummary, *this); 1127 1128 // Effects on the parameters. 1129 unsigned parm_idx = 0; 1130 for (FunctionDecl::param_const_iterator pi = FD->param_begin(), 1131 pe = FD->param_end(); pi != pe; ++pi, ++parm_idx) { 1132 const ParmVarDecl *pd = *pi; 1133 if (pd->getAttr<NSConsumedAttr>()) { 1134 if (!GCEnabled) { 1135 Template->addArg(AF, parm_idx, DecRef); 1136 } 1137 } else if (pd->getAttr<CFConsumedAttr>()) { 1138 Template->addArg(AF, parm_idx, DecRef); 1139 } 1140 } 1141 1142 QualType RetTy = FD->getResultType(); 1143 1144 // Determine if there is a special return effect for this method. 1145 if (cocoa::isCocoaObjectRef(RetTy)) { 1146 if (FD->getAttr<NSReturnsRetainedAttr>()) { 1147 Template->setRetEffect(ObjCAllocRetE); 1148 } 1149 else if (FD->getAttr<CFReturnsRetainedAttr>()) { 1150 Template->setRetEffect(RetEffect::MakeOwned(RetEffect::CF, true)); 1151 } 1152 else if (FD->getAttr<NSReturnsNotRetainedAttr>()) { 1153 Template->setRetEffect(RetEffect::MakeNotOwned(RetEffect::ObjC)); 1154 } 1155 else if (FD->getAttr<CFReturnsNotRetainedAttr>()) { 1156 Template->setRetEffect(RetEffect::MakeNotOwned(RetEffect::CF)); 1157 } 1158 } else if (RetTy->getAs<PointerType>()) { 1159 if (FD->getAttr<CFReturnsRetainedAttr>()) { 1160 Template->setRetEffect(RetEffect::MakeOwned(RetEffect::CF, true)); 1161 } 1162 else if (FD->getAttr<CFReturnsNotRetainedAttr>()) { 1163 Template->setRetEffect(RetEffect::MakeNotOwned(RetEffect::CF)); 1164 } 1165 } 1166} 1167 1168void 1169RetainSummaryManager::updateSummaryFromAnnotations(const RetainSummary *&Summ, 1170 const ObjCMethodDecl *MD) { 1171 if (!MD) 1172 return; 1173 1174 RetainSummaryTemplate Template(Summ, DefaultSummary, *this); 1175 bool isTrackedLoc = false; 1176 1177 // Effects on the receiver. 1178 if (MD->getAttr<NSConsumesSelfAttr>()) { 1179 if (!GCEnabled) 1180 Template->setReceiverEffect(DecRefMsg); 1181 } 1182 1183 // Effects on the parameters. 1184 unsigned parm_idx = 0; 1185 for (ObjCMethodDecl::param_const_iterator 1186 pi=MD->param_begin(), pe=MD->param_end(); 1187 pi != pe; ++pi, ++parm_idx) { 1188 const ParmVarDecl *pd = *pi; 1189 if (pd->getAttr<NSConsumedAttr>()) { 1190 if (!GCEnabled) 1191 Template->addArg(AF, parm_idx, DecRef); 1192 } 1193 else if(pd->getAttr<CFConsumedAttr>()) { 1194 Template->addArg(AF, parm_idx, DecRef); 1195 } 1196 } 1197 1198 // Determine if there is a special return effect for this method. 1199 if (cocoa::isCocoaObjectRef(MD->getResultType())) { 1200 if (MD->getAttr<NSReturnsRetainedAttr>()) { 1201 Template->setRetEffect(ObjCAllocRetE); 1202 return; 1203 } 1204 if (MD->getAttr<NSReturnsNotRetainedAttr>()) { 1205 Template->setRetEffect(RetEffect::MakeNotOwned(RetEffect::ObjC)); 1206 return; 1207 } 1208 1209 isTrackedLoc = true; 1210 } else { 1211 isTrackedLoc = MD->getResultType()->getAs<PointerType>() != NULL; 1212 } 1213 1214 if (isTrackedLoc) { 1215 if (MD->getAttr<CFReturnsRetainedAttr>()) 1216 Template->setRetEffect(RetEffect::MakeOwned(RetEffect::CF, true)); 1217 else if (MD->getAttr<CFReturnsNotRetainedAttr>()) 1218 Template->setRetEffect(RetEffect::MakeNotOwned(RetEffect::CF)); 1219 } 1220} 1221 1222const RetainSummary * 1223RetainSummaryManager::getCommonMethodSummary(const ObjCMethodDecl *MD, 1224 Selector S, QualType RetTy) { 1225 1226 if (MD) { 1227 // Scan the method decl for 'void*' arguments. These should be treated 1228 // as 'StopTracking' because they are often used with delegates. 1229 // Delegates are a frequent form of false positives with the retain 1230 // count checker. 1231 unsigned i = 0; 1232 for (ObjCMethodDecl::param_const_iterator I = MD->param_begin(), 1233 E = MD->param_end(); I != E; ++I, ++i) 1234 if (const ParmVarDecl *PD = *I) { 1235 QualType Ty = Ctx.getCanonicalType(PD->getType()); 1236 if (Ty.getLocalUnqualifiedType() == Ctx.VoidPtrTy) 1237 ScratchArgs = AF.add(ScratchArgs, i, StopTracking); 1238 } 1239 } 1240 1241 // Any special effects? 1242 ArgEffect ReceiverEff = DoNothing; 1243 RetEffect ResultEff = RetEffect::MakeNoRet(); 1244 1245 // Check the method family, and apply any default annotations. 1246 switch (MD ? MD->getMethodFamily() : S.getMethodFamily()) { 1247 case OMF_None: 1248 case OMF_performSelector: 1249 // Assume all Objective-C methods follow Cocoa Memory Management rules. 1250 // FIXME: Does the non-threaded performSelector family really belong here? 1251 // The selector could be, say, @selector(copy). 1252 if (cocoa::isCocoaObjectRef(RetTy)) 1253 ResultEff = RetEffect::MakeNotOwned(RetEffect::ObjC); 1254 else if (coreFoundation::isCFObjectRef(RetTy)) { 1255 // ObjCMethodDecl currently doesn't consider CF objects as valid return 1256 // values for alloc, new, copy, or mutableCopy, so we have to 1257 // double-check with the selector. This is ugly, but there aren't that 1258 // many Objective-C methods that return CF objects, right? 1259 if (MD) { 1260 switch (S.getMethodFamily()) { 1261 case OMF_alloc: 1262 case OMF_new: 1263 case OMF_copy: 1264 case OMF_mutableCopy: 1265 ResultEff = RetEffect::MakeOwned(RetEffect::CF, true); 1266 break; 1267 default: 1268 ResultEff = RetEffect::MakeNotOwned(RetEffect::CF); 1269 break; 1270 } 1271 } else { 1272 ResultEff = RetEffect::MakeNotOwned(RetEffect::CF); 1273 } 1274 } 1275 break; 1276 case OMF_init: 1277 ResultEff = ObjCInitRetE; 1278 ReceiverEff = DecRefMsg; 1279 break; 1280 case OMF_alloc: 1281 case OMF_new: 1282 case OMF_copy: 1283 case OMF_mutableCopy: 1284 if (cocoa::isCocoaObjectRef(RetTy)) 1285 ResultEff = ObjCAllocRetE; 1286 else if (coreFoundation::isCFObjectRef(RetTy)) 1287 ResultEff = RetEffect::MakeOwned(RetEffect::CF, true); 1288 break; 1289 case OMF_autorelease: 1290 ReceiverEff = Autorelease; 1291 break; 1292 case OMF_retain: 1293 ReceiverEff = IncRefMsg; 1294 break; 1295 case OMF_release: 1296 ReceiverEff = DecRefMsg; 1297 break; 1298 case OMF_dealloc: 1299 ReceiverEff = Dealloc; 1300 break; 1301 case OMF_self: 1302 // -self is handled specially by the ExprEngine to propagate the receiver. 1303 break; 1304 case OMF_retainCount: 1305 case OMF_finalize: 1306 // These methods don't return objects. 1307 break; 1308 } 1309 1310 // If one of the arguments in the selector has the keyword 'delegate' we 1311 // should stop tracking the reference count for the receiver. This is 1312 // because the reference count is quite possibly handled by a delegate 1313 // method. 1314 if (S.isKeywordSelector()) { 1315 const std::string &str = S.getAsString(); 1316 assert(!str.empty()); 1317 if (StrInStrNoCase(str, "delegate:") != StringRef::npos) 1318 ReceiverEff = StopTracking; 1319 } 1320 1321 if (ScratchArgs.isEmpty() && ReceiverEff == DoNothing && 1322 ResultEff.getKind() == RetEffect::NoRet) 1323 return getDefaultSummary(); 1324 1325 return getPersistentSummary(ResultEff, ReceiverEff, MayEscape); 1326} 1327 1328const RetainSummary * 1329RetainSummaryManager::getInstanceMethodSummary(const ObjCMessage &msg, 1330 ProgramStateRef state, 1331 const LocationContext *LC) { 1332 1333 // We need the type-information of the tracked receiver object 1334 // Retrieve it from the state. 1335 const Expr *Receiver = msg.getInstanceReceiver(); 1336 const ObjCInterfaceDecl *ID = 0; 1337 1338 // FIXME: Is this really working as expected? There are cases where 1339 // we just use the 'ID' from the message expression. 1340 SVal receiverV; 1341 1342 if (Receiver) { 1343 receiverV = state->getSValAsScalarOrLoc(Receiver, LC); 1344 1345 // FIXME: Eventually replace the use of state->get<RefBindings> with 1346 // a generic API for reasoning about the Objective-C types of symbolic 1347 // objects. 1348 if (SymbolRef Sym = receiverV.getAsLocSymbol()) 1349 if (const RefVal *T = state->get<RefBindings>(Sym)) 1350 if (const ObjCObjectPointerType* PT = 1351 T->getType()->getAs<ObjCObjectPointerType>()) 1352 ID = PT->getInterfaceDecl(); 1353 1354 // FIXME: this is a hack. This may or may not be the actual method 1355 // that is called. 1356 if (!ID) { 1357 if (const ObjCObjectPointerType *PT = 1358 Receiver->getType()->getAs<ObjCObjectPointerType>()) 1359 ID = PT->getInterfaceDecl(); 1360 } 1361 } else { 1362 // FIXME: Hack for 'super'. 1363 ID = msg.getReceiverInterface(); 1364 } 1365 1366 // FIXME: The receiver could be a reference to a class, meaning that 1367 // we should use the class method. 1368 return getInstanceMethodSummary(msg, ID); 1369} 1370 1371const RetainSummary * 1372RetainSummaryManager::getInstanceMethodSummary(Selector S, 1373 IdentifierInfo *ClsName, 1374 const ObjCInterfaceDecl *ID, 1375 const ObjCMethodDecl *MD, 1376 QualType RetTy) { 1377 1378 // Look up a summary in our summary cache. 1379 const RetainSummary *Summ = ObjCMethodSummaries.find(ID, ClsName, S); 1380 1381 if (!Summ) { 1382 Summ = getCommonMethodSummary(MD, S, RetTy); 1383 1384 // Annotations override defaults. 1385 updateSummaryFromAnnotations(Summ, MD); 1386 1387 // Memoize the summary. 1388 ObjCMethodSummaries[ObjCSummaryKey(ID, ClsName, S)] = Summ; 1389 } 1390 1391 return Summ; 1392} 1393 1394const RetainSummary * 1395RetainSummaryManager::getClassMethodSummary(Selector S, IdentifierInfo *ClsName, 1396 const ObjCInterfaceDecl *ID, 1397 const ObjCMethodDecl *MD, 1398 QualType RetTy) { 1399 1400 assert(ClsName && "Class name must be specified."); 1401 const RetainSummary *Summ = ObjCClassMethodSummaries.find(ID, ClsName, S); 1402 1403 if (!Summ) { 1404 Summ = getCommonMethodSummary(MD, S, RetTy); 1405 1406 // Annotations override defaults. 1407 updateSummaryFromAnnotations(Summ, MD); 1408 1409 // Memoize the summary. 1410 ObjCClassMethodSummaries[ObjCSummaryKey(ID, ClsName, S)] = Summ; 1411 } 1412 1413 return Summ; 1414} 1415 1416void RetainSummaryManager::InitializeClassMethodSummaries() { 1417 assert(ScratchArgs.isEmpty()); 1418 // Create the [NSAssertionHandler currentHander] summary. 1419 addClassMethSummary("NSAssertionHandler", "currentHandler", 1420 getPersistentSummary(RetEffect::MakeNotOwned(RetEffect::ObjC))); 1421 1422 // Create the [NSAutoreleasePool addObject:] summary. 1423 ScratchArgs = AF.add(ScratchArgs, 0, Autorelease); 1424 addClassMethSummary("NSAutoreleasePool", "addObject", 1425 getPersistentSummary(RetEffect::MakeNoRet(), 1426 DoNothing, Autorelease)); 1427 1428 // Create the summaries for [NSObject performSelector...]. We treat 1429 // these as 'stop tracking' for the arguments because they are often 1430 // used for delegates that can release the object. When we have better 1431 // inter-procedural analysis we can potentially do something better. This 1432 // workaround is to remove false positives. 1433 const RetainSummary *Summ = 1434 getPersistentSummary(RetEffect::MakeNoRet(), DoNothing, StopTracking); 1435 IdentifierInfo *NSObjectII = &Ctx.Idents.get("NSObject"); 1436 addClsMethSummary(NSObjectII, Summ, "performSelector", "withObject", 1437 "afterDelay", NULL); 1438 addClsMethSummary(NSObjectII, Summ, "performSelector", "withObject", 1439 "afterDelay", "inModes", NULL); 1440 addClsMethSummary(NSObjectII, Summ, "performSelectorOnMainThread", 1441 "withObject", "waitUntilDone", NULL); 1442 addClsMethSummary(NSObjectII, Summ, "performSelectorOnMainThread", 1443 "withObject", "waitUntilDone", "modes", NULL); 1444 addClsMethSummary(NSObjectII, Summ, "performSelector", "onThread", 1445 "withObject", "waitUntilDone", NULL); 1446 addClsMethSummary(NSObjectII, Summ, "performSelector", "onThread", 1447 "withObject", "waitUntilDone", "modes", NULL); 1448 addClsMethSummary(NSObjectII, Summ, "performSelectorInBackground", 1449 "withObject", NULL); 1450} 1451 1452void RetainSummaryManager::InitializeMethodSummaries() { 1453 1454 assert (ScratchArgs.isEmpty()); 1455 1456 // Create the "init" selector. It just acts as a pass-through for the 1457 // receiver. 1458 const RetainSummary *InitSumm = getPersistentSummary(ObjCInitRetE, DecRefMsg); 1459 addNSObjectMethSummary(GetNullarySelector("init", Ctx), InitSumm); 1460 1461 // awakeAfterUsingCoder: behaves basically like an 'init' method. It 1462 // claims the receiver and returns a retained object. 1463 addNSObjectMethSummary(GetUnarySelector("awakeAfterUsingCoder", Ctx), 1464 InitSumm); 1465 1466 // The next methods are allocators. 1467 const RetainSummary *AllocSumm = getPersistentSummary(ObjCAllocRetE); 1468 const RetainSummary *CFAllocSumm = 1469 getPersistentSummary(RetEffect::MakeOwned(RetEffect::CF, true)); 1470 1471 // Create the "retain" selector. 1472 RetEffect NoRet = RetEffect::MakeNoRet(); 1473 const RetainSummary *Summ = getPersistentSummary(NoRet, IncRefMsg); 1474 addNSObjectMethSummary(GetNullarySelector("retain", Ctx), Summ); 1475 1476 // Create the "release" selector. 1477 Summ = getPersistentSummary(NoRet, DecRefMsg); 1478 addNSObjectMethSummary(GetNullarySelector("release", Ctx), Summ); 1479 1480 // Create the "drain" selector. 1481 Summ = getPersistentSummary(NoRet, isGCEnabled() ? DoNothing : DecRef); 1482 addNSObjectMethSummary(GetNullarySelector("drain", Ctx), Summ); 1483 1484 // Create the -dealloc summary. 1485 Summ = getPersistentSummary(NoRet, Dealloc); 1486 addNSObjectMethSummary(GetNullarySelector("dealloc", Ctx), Summ); 1487 1488 // Create the "autorelease" selector. 1489 Summ = getPersistentSummary(NoRet, Autorelease); 1490 addNSObjectMethSummary(GetNullarySelector("autorelease", Ctx), Summ); 1491 1492 // Specially handle NSAutoreleasePool. 1493 addInstMethSummary("NSAutoreleasePool", "init", 1494 getPersistentSummary(NoRet, NewAutoreleasePool)); 1495 1496 // For NSWindow, allocated objects are (initially) self-owned. 1497 // FIXME: For now we opt for false negatives with NSWindow, as these objects 1498 // self-own themselves. However, they only do this once they are displayed. 1499 // Thus, we need to track an NSWindow's display status. 1500 // This is tracked in <rdar://problem/6062711>. 1501 // See also http://llvm.org/bugs/show_bug.cgi?id=3714. 1502 const RetainSummary *NoTrackYet = getPersistentSummary(RetEffect::MakeNoRet(), 1503 StopTracking, 1504 StopTracking); 1505 1506 addClassMethSummary("NSWindow", "alloc", NoTrackYet); 1507 1508#if 0 1509 addInstMethSummary("NSWindow", NoTrackYet, "initWithContentRect", 1510 "styleMask", "backing", "defer", NULL); 1511 1512 addInstMethSummary("NSWindow", NoTrackYet, "initWithContentRect", 1513 "styleMask", "backing", "defer", "screen", NULL); 1514#endif 1515 1516 // For NSPanel (which subclasses NSWindow), allocated objects are not 1517 // self-owned. 1518 // FIXME: For now we don't track NSPanels. object for the same reason 1519 // as for NSWindow objects. 1520 addClassMethSummary("NSPanel", "alloc", NoTrackYet); 1521 1522#if 0 1523 addInstMethSummary("NSPanel", NoTrackYet, "initWithContentRect", 1524 "styleMask", "backing", "defer", NULL); 1525 1526 addInstMethSummary("NSPanel", NoTrackYet, "initWithContentRect", 1527 "styleMask", "backing", "defer", "screen", NULL); 1528#endif 1529 1530 // Don't track allocated autorelease pools yet, as it is okay to prematurely 1531 // exit a method. 1532 addClassMethSummary("NSAutoreleasePool", "alloc", NoTrackYet); 1533 addClassMethSummary("NSAutoreleasePool", "allocWithZone", NoTrackYet, false); 1534 1535 // Create summaries QCRenderer/QCView -createSnapShotImageOfType: 1536 addInstMethSummary("QCRenderer", AllocSumm, 1537 "createSnapshotImageOfType", NULL); 1538 addInstMethSummary("QCView", AllocSumm, 1539 "createSnapshotImageOfType", NULL); 1540 1541 // Create summaries for CIContext, 'createCGImage' and 1542 // 'createCGLayerWithSize'. These objects are CF objects, and are not 1543 // automatically garbage collected. 1544 addInstMethSummary("CIContext", CFAllocSumm, 1545 "createCGImage", "fromRect", NULL); 1546 addInstMethSummary("CIContext", CFAllocSumm, 1547 "createCGImage", "fromRect", "format", "colorSpace", NULL); 1548 addInstMethSummary("CIContext", CFAllocSumm, "createCGLayerWithSize", 1549 "info", NULL); 1550} 1551 1552//===----------------------------------------------------------------------===// 1553// AutoreleaseBindings - State used to track objects in autorelease pools. 1554//===----------------------------------------------------------------------===// 1555 1556typedef llvm::ImmutableMap<SymbolRef, unsigned> ARCounts; 1557typedef llvm::ImmutableMap<SymbolRef, ARCounts> ARPoolContents; 1558typedef llvm::ImmutableList<SymbolRef> ARStack; 1559 1560static int AutoRCIndex = 0; 1561static int AutoRBIndex = 0; 1562 1563namespace { class AutoreleasePoolContents {}; } 1564namespace { class AutoreleaseStack {}; } 1565 1566namespace clang { 1567namespace ento { 1568template<> struct ProgramStateTrait<AutoreleaseStack> 1569 : public ProgramStatePartialTrait<ARStack> { 1570 static inline void *GDMIndex() { return &AutoRBIndex; } 1571}; 1572 1573template<> struct ProgramStateTrait<AutoreleasePoolContents> 1574 : public ProgramStatePartialTrait<ARPoolContents> { 1575 static inline void *GDMIndex() { return &AutoRCIndex; } 1576}; 1577} // end GR namespace 1578} // end clang namespace 1579 1580static SymbolRef GetCurrentAutoreleasePool(ProgramStateRef state) { 1581 ARStack stack = state->get<AutoreleaseStack>(); 1582 return stack.isEmpty() ? SymbolRef() : stack.getHead(); 1583} 1584 1585static ProgramStateRef 1586SendAutorelease(ProgramStateRef state, 1587 ARCounts::Factory &F, 1588 SymbolRef sym) { 1589 SymbolRef pool = GetCurrentAutoreleasePool(state); 1590 const ARCounts *cnts = state->get<AutoreleasePoolContents>(pool); 1591 ARCounts newCnts(0); 1592 1593 if (cnts) { 1594 const unsigned *cnt = (*cnts).lookup(sym); 1595 newCnts = F.add(*cnts, sym, cnt ? *cnt + 1 : 1); 1596 } 1597 else 1598 newCnts = F.add(F.getEmptyMap(), sym, 1); 1599 1600 return state->set<AutoreleasePoolContents>(pool, newCnts); 1601} 1602 1603//===----------------------------------------------------------------------===// 1604// Error reporting. 1605//===----------------------------------------------------------------------===// 1606namespace { 1607 typedef llvm::DenseMap<const ExplodedNode *, const RetainSummary *> 1608 SummaryLogTy; 1609 1610 //===-------------===// 1611 // Bug Descriptions. // 1612 //===-------------===// 1613 1614 class CFRefBug : public BugType { 1615 protected: 1616 CFRefBug(StringRef name) 1617 : BugType(name, "Memory (Core Foundation/Objective-C)") {} 1618 public: 1619 1620 // FIXME: Eventually remove. 1621 virtual const char *getDescription() const = 0; 1622 1623 virtual bool isLeak() const { return false; } 1624 }; 1625 1626 class UseAfterRelease : public CFRefBug { 1627 public: 1628 UseAfterRelease() : CFRefBug("Use-after-release") {} 1629 1630 const char *getDescription() const { 1631 return "Reference-counted object is used after it is released"; 1632 } 1633 }; 1634 1635 class BadRelease : public CFRefBug { 1636 public: 1637 BadRelease() : CFRefBug("Bad release") {} 1638 1639 const char *getDescription() const { 1640 return "Incorrect decrement of the reference count of an object that is " 1641 "not owned at this point by the caller"; 1642 } 1643 }; 1644 1645 class DeallocGC : public CFRefBug { 1646 public: 1647 DeallocGC() 1648 : CFRefBug("-dealloc called while using garbage collection") {} 1649 1650 const char *getDescription() const { 1651 return "-dealloc called while using garbage collection"; 1652 } 1653 }; 1654 1655 class DeallocNotOwned : public CFRefBug { 1656 public: 1657 DeallocNotOwned() 1658 : CFRefBug("-dealloc sent to non-exclusively owned object") {} 1659 1660 const char *getDescription() const { 1661 return "-dealloc sent to object that may be referenced elsewhere"; 1662 } 1663 }; 1664 1665 class OverAutorelease : public CFRefBug { 1666 public: 1667 OverAutorelease() 1668 : CFRefBug("Object sent -autorelease too many times") {} 1669 1670 const char *getDescription() const { 1671 return "Object sent -autorelease too many times"; 1672 } 1673 }; 1674 1675 class ReturnedNotOwnedForOwned : public CFRefBug { 1676 public: 1677 ReturnedNotOwnedForOwned() 1678 : CFRefBug("Method should return an owned object") {} 1679 1680 const char *getDescription() const { 1681 return "Object with a +0 retain count returned to caller where a +1 " 1682 "(owning) retain count is expected"; 1683 } 1684 }; 1685 1686 class Leak : public CFRefBug { 1687 const bool isReturn; 1688 protected: 1689 Leak(StringRef name, bool isRet) 1690 : CFRefBug(name), isReturn(isRet) { 1691 // Leaks should not be reported if they are post-dominated by a sink. 1692 setSuppressOnSink(true); 1693 } 1694 public: 1695 1696 const char *getDescription() const { return ""; } 1697 1698 bool isLeak() const { return true; } 1699 }; 1700 1701 class LeakAtReturn : public Leak { 1702 public: 1703 LeakAtReturn(StringRef name) 1704 : Leak(name, true) {} 1705 }; 1706 1707 class LeakWithinFunction : public Leak { 1708 public: 1709 LeakWithinFunction(StringRef name) 1710 : Leak(name, false) {} 1711 }; 1712 1713 //===---------===// 1714 // Bug Reports. // 1715 //===---------===// 1716 1717 class CFRefReportVisitor : public BugReporterVisitor { 1718 protected: 1719 SymbolRef Sym; 1720 const SummaryLogTy &SummaryLog; 1721 bool GCEnabled; 1722 1723 public: 1724 CFRefReportVisitor(SymbolRef sym, bool gcEnabled, const SummaryLogTy &log) 1725 : Sym(sym), SummaryLog(log), GCEnabled(gcEnabled) {} 1726 1727 virtual void Profile(llvm::FoldingSetNodeID &ID) const { 1728 static int x = 0; 1729 ID.AddPointer(&x); 1730 ID.AddPointer(Sym); 1731 } 1732 1733 virtual PathDiagnosticPiece *VisitNode(const ExplodedNode *N, 1734 const ExplodedNode *PrevN, 1735 BugReporterContext &BRC, 1736 BugReport &BR); 1737 1738 virtual PathDiagnosticPiece *getEndPath(BugReporterContext &BRC, 1739 const ExplodedNode *N, 1740 BugReport &BR); 1741 }; 1742 1743 class CFRefLeakReportVisitor : public CFRefReportVisitor { 1744 public: 1745 CFRefLeakReportVisitor(SymbolRef sym, bool GCEnabled, 1746 const SummaryLogTy &log) 1747 : CFRefReportVisitor(sym, GCEnabled, log) {} 1748 1749 PathDiagnosticPiece *getEndPath(BugReporterContext &BRC, 1750 const ExplodedNode *N, 1751 BugReport &BR); 1752 }; 1753 1754 class CFRefReport : public BugReport { 1755 void addGCModeDescription(const LangOptions &LOpts, bool GCEnabled); 1756 1757 public: 1758 CFRefReport(CFRefBug &D, const LangOptions &LOpts, bool GCEnabled, 1759 const SummaryLogTy &Log, ExplodedNode *n, SymbolRef sym, 1760 bool registerVisitor = true) 1761 : BugReport(D, D.getDescription(), n) { 1762 if (registerVisitor) 1763 addVisitor(new CFRefReportVisitor(sym, GCEnabled, Log)); 1764 addGCModeDescription(LOpts, GCEnabled); 1765 } 1766 1767 CFRefReport(CFRefBug &D, const LangOptions &LOpts, bool GCEnabled, 1768 const SummaryLogTy &Log, ExplodedNode *n, SymbolRef sym, 1769 StringRef endText) 1770 : BugReport(D, D.getDescription(), endText, n) { 1771 addVisitor(new CFRefReportVisitor(sym, GCEnabled, Log)); 1772 addGCModeDescription(LOpts, GCEnabled); 1773 } 1774 1775 virtual std::pair<ranges_iterator, ranges_iterator> getRanges() { 1776 const CFRefBug& BugTy = static_cast<CFRefBug&>(getBugType()); 1777 if (!BugTy.isLeak()) 1778 return BugReport::getRanges(); 1779 else 1780 return std::make_pair(ranges_iterator(), ranges_iterator()); 1781 } 1782 }; 1783 1784 class CFRefLeakReport : public CFRefReport { 1785 const MemRegion* AllocBinding; 1786 1787 public: 1788 CFRefLeakReport(CFRefBug &D, const LangOptions &LOpts, bool GCEnabled, 1789 const SummaryLogTy &Log, ExplodedNode *n, SymbolRef sym, 1790 CheckerContext &Ctx); 1791 1792 PathDiagnosticLocation getLocation(const SourceManager &SM) const { 1793 assert(Location.isValid()); 1794 return Location; 1795 } 1796 }; 1797} // end anonymous namespace 1798 1799void CFRefReport::addGCModeDescription(const LangOptions &LOpts, 1800 bool GCEnabled) { 1801 const char *GCModeDescription = 0; 1802 1803 switch (LOpts.getGC()) { 1804 case LangOptions::GCOnly: 1805 assert(GCEnabled); 1806 GCModeDescription = "Code is compiled to only use garbage collection"; 1807 break; 1808 1809 case LangOptions::NonGC: 1810 assert(!GCEnabled); 1811 GCModeDescription = "Code is compiled to use reference counts"; 1812 break; 1813 1814 case LangOptions::HybridGC: 1815 if (GCEnabled) { 1816 GCModeDescription = "Code is compiled to use either garbage collection " 1817 "(GC) or reference counts (non-GC). The bug occurs " 1818 "with GC enabled"; 1819 break; 1820 } else { 1821 GCModeDescription = "Code is compiled to use either garbage collection " 1822 "(GC) or reference counts (non-GC). The bug occurs " 1823 "in non-GC mode"; 1824 break; 1825 } 1826 } 1827 1828 assert(GCModeDescription && "invalid/unknown GC mode"); 1829 addExtraText(GCModeDescription); 1830} 1831 1832// FIXME: This should be a method on SmallVector. 1833static inline bool contains(const SmallVectorImpl<ArgEffect>& V, 1834 ArgEffect X) { 1835 for (SmallVectorImpl<ArgEffect>::const_iterator I=V.begin(), E=V.end(); 1836 I!=E; ++I) 1837 if (*I == X) return true; 1838 1839 return false; 1840} 1841 1842static bool isPropertyAccess(const Stmt *S, ParentMap &PM) { 1843 unsigned maxDepth = 4; 1844 while (S && maxDepth) { 1845 if (const PseudoObjectExpr *PO = dyn_cast<PseudoObjectExpr>(S)) { 1846 if (!isa<ObjCMessageExpr>(PO->getSyntacticForm())) 1847 return true; 1848 return false; 1849 } 1850 S = PM.getParent(S); 1851 --maxDepth; 1852 } 1853 return false; 1854} 1855 1856PathDiagnosticPiece *CFRefReportVisitor::VisitNode(const ExplodedNode *N, 1857 const ExplodedNode *PrevN, 1858 BugReporterContext &BRC, 1859 BugReport &BR) { 1860 1861 if (!isa<StmtPoint>(N->getLocation())) 1862 return NULL; 1863 1864 // Check if the type state has changed. 1865 ProgramStateRef PrevSt = PrevN->getState(); 1866 ProgramStateRef CurrSt = N->getState(); 1867 const LocationContext *LCtx = N->getLocationContext(); 1868 1869 const RefVal* CurrT = CurrSt->get<RefBindings>(Sym); 1870 if (!CurrT) return NULL; 1871 1872 const RefVal &CurrV = *CurrT; 1873 const RefVal *PrevT = PrevSt->get<RefBindings>(Sym); 1874 1875 // Create a string buffer to constain all the useful things we want 1876 // to tell the user. 1877 std::string sbuf; 1878 llvm::raw_string_ostream os(sbuf); 1879 1880 // This is the allocation site since the previous node had no bindings 1881 // for this symbol. 1882 if (!PrevT) { 1883 const Stmt *S = cast<StmtPoint>(N->getLocation()).getStmt(); 1884 1885 if (isa<ObjCArrayLiteral>(S)) { 1886 os << "NSArray literal is an object with a +0 retain count"; 1887 } 1888 else if (isa<ObjCDictionaryLiteral>(S)) { 1889 os << "NSDictionary literal is an object with a +0 retain count"; 1890 } 1891 else { 1892 if (const CallExpr *CE = dyn_cast<CallExpr>(S)) { 1893 // Get the name of the callee (if it is available). 1894 SVal X = CurrSt->getSValAsScalarOrLoc(CE->getCallee(), LCtx); 1895 if (const FunctionDecl *FD = X.getAsFunctionDecl()) 1896 os << "Call to function '" << *FD << '\''; 1897 else 1898 os << "function call"; 1899 } 1900 else { 1901 assert(isa<ObjCMessageExpr>(S)); 1902 // The message expression may have between written directly or as 1903 // a property access. Lazily determine which case we are looking at. 1904 os << (isPropertyAccess(S, N->getParentMap()) ? "Property" : "Method"); 1905 } 1906 1907 if (CurrV.getObjKind() == RetEffect::CF) { 1908 os << " returns a Core Foundation object with a "; 1909 } 1910 else { 1911 assert (CurrV.getObjKind() == RetEffect::ObjC); 1912 os << " returns an Objective-C object with a "; 1913 } 1914 1915 if (CurrV.isOwned()) { 1916 os << "+1 retain count"; 1917 1918 if (GCEnabled) { 1919 assert(CurrV.getObjKind() == RetEffect::CF); 1920 os << ". " 1921 "Core Foundation objects are not automatically garbage collected."; 1922 } 1923 } 1924 else { 1925 assert (CurrV.isNotOwned()); 1926 os << "+0 retain count"; 1927 } 1928 } 1929 1930 PathDiagnosticLocation Pos(S, BRC.getSourceManager(), 1931 N->getLocationContext()); 1932 return new PathDiagnosticEventPiece(Pos, os.str()); 1933 } 1934 1935 // Gather up the effects that were performed on the object at this 1936 // program point 1937 SmallVector<ArgEffect, 2> AEffects; 1938 1939 const ExplodedNode *OrigNode = BRC.getNodeResolver().getOriginalNode(N); 1940 if (const RetainSummary *Summ = SummaryLog.lookup(OrigNode)) { 1941 // We only have summaries attached to nodes after evaluating CallExpr and 1942 // ObjCMessageExprs. 1943 const Stmt *S = cast<StmtPoint>(N->getLocation()).getStmt(); 1944 1945 if (const CallExpr *CE = dyn_cast<CallExpr>(S)) { 1946 // Iterate through the parameter expressions and see if the symbol 1947 // was ever passed as an argument. 1948 unsigned i = 0; 1949 1950 for (CallExpr::const_arg_iterator AI=CE->arg_begin(), AE=CE->arg_end(); 1951 AI!=AE; ++AI, ++i) { 1952 1953 // Retrieve the value of the argument. Is it the symbol 1954 // we are interested in? 1955 if (CurrSt->getSValAsScalarOrLoc(*AI, LCtx).getAsLocSymbol() != Sym) 1956 continue; 1957 1958 // We have an argument. Get the effect! 1959 AEffects.push_back(Summ->getArg(i)); 1960 } 1961 } 1962 else if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(S)) { 1963 if (const Expr *receiver = ME->getInstanceReceiver()) 1964 if (CurrSt->getSValAsScalarOrLoc(receiver, LCtx) 1965 .getAsLocSymbol() == Sym) { 1966 // The symbol we are tracking is the receiver. 1967 AEffects.push_back(Summ->getReceiverEffect()); 1968 } 1969 } 1970 } 1971 1972 do { 1973 // Get the previous type state. 1974 RefVal PrevV = *PrevT; 1975 1976 // Specially handle -dealloc. 1977 if (!GCEnabled && contains(AEffects, Dealloc)) { 1978 // Determine if the object's reference count was pushed to zero. 1979 assert(!(PrevV == CurrV) && "The typestate *must* have changed."); 1980 // We may not have transitioned to 'release' if we hit an error. 1981 // This case is handled elsewhere. 1982 if (CurrV.getKind() == RefVal::Released) { 1983 assert(CurrV.getCombinedCounts() == 0); 1984 os << "Object released by directly sending the '-dealloc' message"; 1985 break; 1986 } 1987 } 1988 1989 // Specially handle CFMakeCollectable and friends. 1990 if (contains(AEffects, MakeCollectable)) { 1991 // Get the name of the function. 1992 const Stmt *S = cast<StmtPoint>(N->getLocation()).getStmt(); 1993 SVal X = 1994 CurrSt->getSValAsScalarOrLoc(cast<CallExpr>(S)->getCallee(), LCtx); 1995 const FunctionDecl *FD = X.getAsFunctionDecl(); 1996 1997 if (GCEnabled) { 1998 // Determine if the object's reference count was pushed to zero. 1999 assert(!(PrevV == CurrV) && "The typestate *must* have changed."); 2000 2001 os << "In GC mode a call to '" << *FD 2002 << "' decrements an object's retain count and registers the " 2003 "object with the garbage collector. "; 2004 2005 if (CurrV.getKind() == RefVal::Released) { 2006 assert(CurrV.getCount() == 0); 2007 os << "Since it now has a 0 retain count the object can be " 2008 "automatically collected by the garbage collector."; 2009 } 2010 else 2011 os << "An object must have a 0 retain count to be garbage collected. " 2012 "After this call its retain count is +" << CurrV.getCount() 2013 << '.'; 2014 } 2015 else 2016 os << "When GC is not enabled a call to '" << *FD 2017 << "' has no effect on its argument."; 2018 2019 // Nothing more to say. 2020 break; 2021 } 2022 2023 // Determine if the typestate has changed. 2024 if (!(PrevV == CurrV)) 2025 switch (CurrV.getKind()) { 2026 case RefVal::Owned: 2027 case RefVal::NotOwned: 2028 2029 if (PrevV.getCount() == CurrV.getCount()) { 2030 // Did an autorelease message get sent? 2031 if (PrevV.getAutoreleaseCount() == CurrV.getAutoreleaseCount()) 2032 return 0; 2033 2034 assert(PrevV.getAutoreleaseCount() < CurrV.getAutoreleaseCount()); 2035 os << "Object sent -autorelease message"; 2036 break; 2037 } 2038 2039 if (PrevV.getCount() > CurrV.getCount()) 2040 os << "Reference count decremented."; 2041 else 2042 os << "Reference count incremented."; 2043 2044 if (unsigned Count = CurrV.getCount()) 2045 os << " The object now has a +" << Count << " retain count."; 2046 2047 if (PrevV.getKind() == RefVal::Released) { 2048 assert(GCEnabled && CurrV.getCount() > 0); 2049 os << " The object is not eligible for garbage collection until " 2050 "the retain count reaches 0 again."; 2051 } 2052 2053 break; 2054 2055 case RefVal::Released: 2056 os << "Object released."; 2057 break; 2058 2059 case RefVal::ReturnedOwned: 2060 // Autoreleases can be applied after marking a node ReturnedOwned. 2061 if (CurrV.getAutoreleaseCount()) 2062 return NULL; 2063 2064 os << "Object returned to caller as an owning reference (single " 2065 "retain count transferred to caller)"; 2066 break; 2067 2068 case RefVal::ReturnedNotOwned: 2069 os << "Object returned to caller with a +0 retain count"; 2070 break; 2071 2072 default: 2073 return NULL; 2074 } 2075 2076 // Emit any remaining diagnostics for the argument effects (if any). 2077 for (SmallVectorImpl<ArgEffect>::iterator I=AEffects.begin(), 2078 E=AEffects.end(); I != E; ++I) { 2079 2080 // A bunch of things have alternate behavior under GC. 2081 if (GCEnabled) 2082 switch (*I) { 2083 default: break; 2084 case Autorelease: 2085 os << "In GC mode an 'autorelease' has no effect."; 2086 continue; 2087 case IncRefMsg: 2088 os << "In GC mode the 'retain' message has no effect."; 2089 continue; 2090 case DecRefMsg: 2091 os << "In GC mode the 'release' message has no effect."; 2092 continue; 2093 } 2094 } 2095 } while (0); 2096 2097 if (os.str().empty()) 2098 return 0; // We have nothing to say! 2099 2100 const Stmt *S = cast<StmtPoint>(N->getLocation()).getStmt(); 2101 PathDiagnosticLocation Pos(S, BRC.getSourceManager(), 2102 N->getLocationContext()); 2103 PathDiagnosticPiece *P = new PathDiagnosticEventPiece(Pos, os.str()); 2104 2105 // Add the range by scanning the children of the statement for any bindings 2106 // to Sym. 2107 for (Stmt::const_child_iterator I = S->child_begin(), E = S->child_end(); 2108 I!=E; ++I) 2109 if (const Expr *Exp = dyn_cast_or_null<Expr>(*I)) 2110 if (CurrSt->getSValAsScalarOrLoc(Exp, LCtx).getAsLocSymbol() == Sym) { 2111 P->addRange(Exp->getSourceRange()); 2112 break; 2113 } 2114 2115 return P; 2116} 2117 2118namespace { 2119 class FindUniqueBinding : 2120 public StoreManager::BindingsHandler { 2121 SymbolRef Sym; 2122 const MemRegion* Binding; 2123 bool First; 2124 2125 public: 2126 FindUniqueBinding(SymbolRef sym) : Sym(sym), Binding(0), First(true) {} 2127 2128 bool HandleBinding(StoreManager& SMgr, Store store, const MemRegion* R, 2129 SVal val) { 2130 2131 SymbolRef SymV = val.getAsSymbol(); 2132 if (!SymV || SymV != Sym) 2133 return true; 2134 2135 if (Binding) { 2136 First = false; 2137 return false; 2138 } 2139 else 2140 Binding = R; 2141 2142 return true; 2143 } 2144 2145 operator bool() { return First && Binding; } 2146 const MemRegion *getRegion() { return Binding; } 2147 }; 2148} 2149 2150// Find the first node in the current function context that referred to the 2151// tracked symbol and the memory location that value was stored to. Note, the 2152// value is only reported if the allocation occurred in the same function as 2153// the leak. 2154static std::pair<const ExplodedNode*,const MemRegion*> 2155GetAllocationSite(ProgramStateManager& StateMgr, const ExplodedNode *N, 2156 SymbolRef Sym) { 2157 const ExplodedNode *Last = N; 2158 const MemRegion* FirstBinding = 0; 2159 const LocationContext *LeakContext = N->getLocationContext(); 2160 2161 while (N) { 2162 ProgramStateRef St = N->getState(); 2163 RefBindings B = St->get<RefBindings>(); 2164 2165 if (!B.lookup(Sym)) 2166 break; 2167 2168 FindUniqueBinding FB(Sym); 2169 StateMgr.iterBindings(St, FB); 2170 if (FB) FirstBinding = FB.getRegion(); 2171 2172 // Allocation node, is the last node in the current context in which the 2173 // symbol was tracked. 2174 if (N->getLocationContext() == LeakContext) 2175 Last = N; 2176 2177 N = N->pred_empty() ? NULL : *(N->pred_begin()); 2178 } 2179 2180 // If allocation happened in a function different from the leak node context, 2181 // do not report the binding. 2182 if (N->getLocationContext() != LeakContext) { 2183 FirstBinding = 0; 2184 } 2185 2186 return std::make_pair(Last, FirstBinding); 2187} 2188 2189PathDiagnosticPiece* 2190CFRefReportVisitor::getEndPath(BugReporterContext &BRC, 2191 const ExplodedNode *EndN, 2192 BugReport &BR) { 2193 BR.markInteresting(Sym); 2194 return BugReporterVisitor::getDefaultEndPath(BRC, EndN, BR); 2195} 2196 2197PathDiagnosticPiece* 2198CFRefLeakReportVisitor::getEndPath(BugReporterContext &BRC, 2199 const ExplodedNode *EndN, 2200 BugReport &BR) { 2201 2202 // Tell the BugReporterContext to report cases when the tracked symbol is 2203 // assigned to different variables, etc. 2204 BR.markInteresting(Sym); 2205 2206 // We are reporting a leak. Walk up the graph to get to the first node where 2207 // the symbol appeared, and also get the first VarDecl that tracked object 2208 // is stored to. 2209 const ExplodedNode *AllocNode = 0; 2210 const MemRegion* FirstBinding = 0; 2211 2212 llvm::tie(AllocNode, FirstBinding) = 2213 GetAllocationSite(BRC.getStateManager(), EndN, Sym); 2214 2215 SourceManager& SM = BRC.getSourceManager(); 2216 2217 // Compute an actual location for the leak. Sometimes a leak doesn't 2218 // occur at an actual statement (e.g., transition between blocks; end 2219 // of function) so we need to walk the graph and compute a real location. 2220 const ExplodedNode *LeakN = EndN; 2221 PathDiagnosticLocation L = PathDiagnosticLocation::createEndOfPath(LeakN, SM); 2222 2223 std::string sbuf; 2224 llvm::raw_string_ostream os(sbuf); 2225 2226 os << "Object leaked: "; 2227 2228 if (FirstBinding) { 2229 os << "object allocated and stored into '" 2230 << FirstBinding->getString() << '\''; 2231 } 2232 else 2233 os << "allocated object"; 2234 2235 // Get the retain count. 2236 const RefVal* RV = EndN->getState()->get<RefBindings>(Sym); 2237 2238 if (RV->getKind() == RefVal::ErrorLeakReturned) { 2239 // FIXME: Per comments in rdar://6320065, "create" only applies to CF 2240 // objects. Only "copy", "alloc", "retain" and "new" transfer ownership 2241 // to the caller for NS objects. 2242 const Decl *D = &EndN->getCodeDecl(); 2243 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 2244 os << " is returned from a method whose name ('" 2245 << MD->getSelector().getAsString() 2246 << "') does not start with 'copy', 'mutableCopy', 'alloc' or 'new'." 2247 " This violates the naming convention rules" 2248 " given in the Memory Management Guide for Cocoa"; 2249 } 2250 else { 2251 const FunctionDecl *FD = cast<FunctionDecl>(D); 2252 os << " is returned from a function whose name ('" 2253 << *FD 2254 << "') does not contain 'Copy' or 'Create'. This violates the naming" 2255 " convention rules given in the Memory Management Guide for Core" 2256 " Foundation"; 2257 } 2258 } 2259 else if (RV->getKind() == RefVal::ErrorGCLeakReturned) { 2260 ObjCMethodDecl &MD = cast<ObjCMethodDecl>(EndN->getCodeDecl()); 2261 os << " and returned from method '" << MD.getSelector().getAsString() 2262 << "' is potentially leaked when using garbage collection. Callers " 2263 "of this method do not expect a returned object with a +1 retain " 2264 "count since they expect the object to be managed by the garbage " 2265 "collector"; 2266 } 2267 else 2268 os << " is not referenced later in this execution path and has a retain " 2269 "count of +" << RV->getCount(); 2270 2271 return new PathDiagnosticEventPiece(L, os.str()); 2272} 2273 2274CFRefLeakReport::CFRefLeakReport(CFRefBug &D, const LangOptions &LOpts, 2275 bool GCEnabled, const SummaryLogTy &Log, 2276 ExplodedNode *n, SymbolRef sym, 2277 CheckerContext &Ctx) 2278: CFRefReport(D, LOpts, GCEnabled, Log, n, sym, false) { 2279 2280 // Most bug reports are cached at the location where they occurred. 2281 // With leaks, we want to unique them by the location where they were 2282 // allocated, and only report a single path. To do this, we need to find 2283 // the allocation site of a piece of tracked memory, which we do via a 2284 // call to GetAllocationSite. This will walk the ExplodedGraph backwards. 2285 // Note that this is *not* the trimmed graph; we are guaranteed, however, 2286 // that all ancestor nodes that represent the allocation site have the 2287 // same SourceLocation. 2288 const ExplodedNode *AllocNode = 0; 2289 2290 const SourceManager& SMgr = Ctx.getSourceManager(); 2291 2292 llvm::tie(AllocNode, AllocBinding) = // Set AllocBinding. 2293 GetAllocationSite(Ctx.getStateManager(), getErrorNode(), sym); 2294 2295 // Get the SourceLocation for the allocation site. 2296 ProgramPoint P = AllocNode->getLocation(); 2297 const Stmt *AllocStmt = cast<PostStmt>(P).getStmt(); 2298 Location = PathDiagnosticLocation::createBegin(AllocStmt, SMgr, 2299 n->getLocationContext()); 2300 // Fill in the description of the bug. 2301 Description.clear(); 2302 llvm::raw_string_ostream os(Description); 2303 os << "Potential leak "; 2304 if (GCEnabled) 2305 os << "(when using garbage collection) "; 2306 os << "of an object"; 2307 2308 // FIXME: AllocBinding doesn't get populated for RegionStore yet. 2309 if (AllocBinding) 2310 os << " stored into '" << AllocBinding->getString() << '\''; 2311 2312 addVisitor(new CFRefLeakReportVisitor(sym, GCEnabled, Log)); 2313} 2314 2315//===----------------------------------------------------------------------===// 2316// Main checker logic. 2317//===----------------------------------------------------------------------===// 2318 2319namespace { 2320class RetainCountChecker 2321 : public Checker< check::Bind, 2322 check::DeadSymbols, 2323 check::EndAnalysis, 2324 check::EndPath, 2325 check::PostStmt<BlockExpr>, 2326 check::PostStmt<CastExpr>, 2327 check::PostStmt<CallExpr>, 2328 check::PostStmt<CXXConstructExpr>, 2329 check::PostStmt<ObjCArrayLiteral>, 2330 check::PostStmt<ObjCDictionaryLiteral>, 2331 check::PostObjCMessage, 2332 check::PreStmt<ReturnStmt>, 2333 check::RegionChanges, 2334 eval::Assume, 2335 eval::Call > { 2336 mutable OwningPtr<CFRefBug> useAfterRelease, releaseNotOwned; 2337 mutable OwningPtr<CFRefBug> deallocGC, deallocNotOwned; 2338 mutable OwningPtr<CFRefBug> overAutorelease, returnNotOwnedForOwned; 2339 mutable OwningPtr<CFRefBug> leakWithinFunction, leakAtReturn; 2340 mutable OwningPtr<CFRefBug> leakWithinFunctionGC, leakAtReturnGC; 2341 2342 typedef llvm::DenseMap<SymbolRef, const SimpleProgramPointTag *> SymbolTagMap; 2343 2344 // This map is only used to ensure proper deletion of any allocated tags. 2345 mutable SymbolTagMap DeadSymbolTags; 2346 2347 mutable OwningPtr<RetainSummaryManager> Summaries; 2348 mutable OwningPtr<RetainSummaryManager> SummariesGC; 2349 2350 mutable ARCounts::Factory ARCountFactory; 2351 2352 mutable SummaryLogTy SummaryLog; 2353 mutable bool ShouldResetSummaryLog; 2354 2355public: 2356 RetainCountChecker() : ShouldResetSummaryLog(false) {} 2357 2358 virtual ~RetainCountChecker() { 2359 DeleteContainerSeconds(DeadSymbolTags); 2360 } 2361 2362 void checkEndAnalysis(ExplodedGraph &G, BugReporter &BR, 2363 ExprEngine &Eng) const { 2364 // FIXME: This is a hack to make sure the summary log gets cleared between 2365 // analyses of different code bodies. 2366 // 2367 // Why is this necessary? Because a checker's lifetime is tied to a 2368 // translation unit, but an ExplodedGraph's lifetime is just a code body. 2369 // Once in a blue moon, a new ExplodedNode will have the same address as an 2370 // old one with an associated summary, and the bug report visitor gets very 2371 // confused. (To make things worse, the summary lifetime is currently also 2372 // tied to a code body, so we get a crash instead of incorrect results.) 2373 // 2374 // Why is this a bad solution? Because if the lifetime of the ExplodedGraph 2375 // changes, things will start going wrong again. Really the lifetime of this 2376 // log needs to be tied to either the specific nodes in it or the entire 2377 // ExplodedGraph, not to a specific part of the code being analyzed. 2378 // 2379 // (Also, having stateful local data means that the same checker can't be 2380 // used from multiple threads, but a lot of checkers have incorrect 2381 // assumptions about that anyway. So that wasn't a priority at the time of 2382 // this fix.) 2383 // 2384 // This happens at the end of analysis, but bug reports are emitted /after/ 2385 // this point. So we can't just clear the summary log now. Instead, we mark 2386 // that the next time we access the summary log, it should be cleared. 2387 2388 // If we never reset the summary log during /this/ code body analysis, 2389 // there were no new summaries. There might still have been summaries from 2390 // the /last/ analysis, so clear them out to make sure the bug report 2391 // visitors don't get confused. 2392 if (ShouldResetSummaryLog) 2393 SummaryLog.clear(); 2394 2395 ShouldResetSummaryLog = !SummaryLog.empty(); 2396 } 2397 2398 CFRefBug *getLeakWithinFunctionBug(const LangOptions &LOpts, 2399 bool GCEnabled) const { 2400 if (GCEnabled) { 2401 if (!leakWithinFunctionGC) 2402 leakWithinFunctionGC.reset(new LeakWithinFunction("Leak of object when " 2403 "using garbage " 2404 "collection")); 2405 return leakWithinFunctionGC.get(); 2406 } else { 2407 if (!leakWithinFunction) { 2408 if (LOpts.getGC() == LangOptions::HybridGC) { 2409 leakWithinFunction.reset(new LeakWithinFunction("Leak of object when " 2410 "not using garbage " 2411 "collection (GC) in " 2412 "dual GC/non-GC " 2413 "code")); 2414 } else { 2415 leakWithinFunction.reset(new LeakWithinFunction("Leak")); 2416 } 2417 } 2418 return leakWithinFunction.get(); 2419 } 2420 } 2421 2422 CFRefBug *getLeakAtReturnBug(const LangOptions &LOpts, bool GCEnabled) const { 2423 if (GCEnabled) { 2424 if (!leakAtReturnGC) 2425 leakAtReturnGC.reset(new LeakAtReturn("Leak of returned object when " 2426 "using garbage collection")); 2427 return leakAtReturnGC.get(); 2428 } else { 2429 if (!leakAtReturn) { 2430 if (LOpts.getGC() == LangOptions::HybridGC) { 2431 leakAtReturn.reset(new LeakAtReturn("Leak of returned object when " 2432 "not using garbage collection " 2433 "(GC) in dual GC/non-GC code")); 2434 } else { 2435 leakAtReturn.reset(new LeakAtReturn("Leak of returned object")); 2436 } 2437 } 2438 return leakAtReturn.get(); 2439 } 2440 } 2441 2442 RetainSummaryManager &getSummaryManager(ASTContext &Ctx, 2443 bool GCEnabled) const { 2444 // FIXME: We don't support ARC being turned on and off during one analysis. 2445 // (nor, for that matter, do we support changing ASTContexts) 2446 bool ARCEnabled = (bool)Ctx.getLangOpts().ObjCAutoRefCount; 2447 if (GCEnabled) { 2448 if (!SummariesGC) 2449 SummariesGC.reset(new RetainSummaryManager(Ctx, true, ARCEnabled)); 2450 else 2451 assert(SummariesGC->isARCEnabled() == ARCEnabled); 2452 return *SummariesGC; 2453 } else { 2454 if (!Summaries) 2455 Summaries.reset(new RetainSummaryManager(Ctx, false, ARCEnabled)); 2456 else 2457 assert(Summaries->isARCEnabled() == ARCEnabled); 2458 return *Summaries; 2459 } 2460 } 2461 2462 RetainSummaryManager &getSummaryManager(CheckerContext &C) const { 2463 return getSummaryManager(C.getASTContext(), C.isObjCGCEnabled()); 2464 } 2465 2466 void printState(raw_ostream &Out, ProgramStateRef State, 2467 const char *NL, const char *Sep) const; 2468 2469 void checkBind(SVal loc, SVal val, const Stmt *S, CheckerContext &C) const; 2470 void checkPostStmt(const BlockExpr *BE, CheckerContext &C) const; 2471 void checkPostStmt(const CastExpr *CE, CheckerContext &C) const; 2472 2473 void checkPostStmt(const CallExpr *CE, CheckerContext &C) const; 2474 void checkPostStmt(const CXXConstructExpr *CE, CheckerContext &C) const; 2475 void checkPostStmt(const ObjCArrayLiteral *AL, CheckerContext &C) const; 2476 void checkPostStmt(const ObjCDictionaryLiteral *DL, CheckerContext &C) const; 2477 void checkPostObjCMessage(const ObjCMessage &Msg, CheckerContext &C) const; 2478 2479 void checkSummary(const RetainSummary &Summ, const CallOrObjCMessage &Call, 2480 CheckerContext &C) const; 2481 2482 bool evalCall(const CallExpr *CE, CheckerContext &C) const; 2483 2484 ProgramStateRef evalAssume(ProgramStateRef state, SVal Cond, 2485 bool Assumption) const; 2486 2487 ProgramStateRef 2488 checkRegionChanges(ProgramStateRef state, 2489 const StoreManager::InvalidatedSymbols *invalidated, 2490 ArrayRef<const MemRegion *> ExplicitRegions, 2491 ArrayRef<const MemRegion *> Regions, 2492 const CallOrObjCMessage *Call) const; 2493 2494 bool wantsRegionChangeUpdate(ProgramStateRef state) const { 2495 return true; 2496 } 2497 2498 void checkPreStmt(const ReturnStmt *S, CheckerContext &C) const; 2499 void checkReturnWithRetEffect(const ReturnStmt *S, CheckerContext &C, 2500 ExplodedNode *Pred, RetEffect RE, RefVal X, 2501 SymbolRef Sym, ProgramStateRef state) const; 2502 2503 void checkDeadSymbols(SymbolReaper &SymReaper, CheckerContext &C) const; 2504 void checkEndPath(CheckerContext &C) const; 2505 2506 ProgramStateRef updateSymbol(ProgramStateRef state, SymbolRef sym, 2507 RefVal V, ArgEffect E, RefVal::Kind &hasErr, 2508 CheckerContext &C) const; 2509 2510 void processNonLeakError(ProgramStateRef St, SourceRange ErrorRange, 2511 RefVal::Kind ErrorKind, SymbolRef Sym, 2512 CheckerContext &C) const; 2513 2514 void processObjCLiterals(CheckerContext &C, const Expr *Ex) const; 2515 2516 const ProgramPointTag *getDeadSymbolTag(SymbolRef sym) const; 2517 2518 ProgramStateRef handleSymbolDeath(ProgramStateRef state, 2519 SymbolRef sid, RefVal V, 2520 SmallVectorImpl<SymbolRef> &Leaked) const; 2521 2522 std::pair<ExplodedNode *, ProgramStateRef > 2523 handleAutoreleaseCounts(ProgramStateRef state, 2524 GenericNodeBuilderRefCount Bd, ExplodedNode *Pred, 2525 CheckerContext &Ctx, SymbolRef Sym, RefVal V) const; 2526 2527 ExplodedNode *processLeaks(ProgramStateRef state, 2528 SmallVectorImpl<SymbolRef> &Leaked, 2529 GenericNodeBuilderRefCount &Builder, 2530 CheckerContext &Ctx, 2531 ExplodedNode *Pred = 0) const; 2532}; 2533} // end anonymous namespace 2534 2535namespace { 2536class StopTrackingCallback : public SymbolVisitor { 2537 ProgramStateRef state; 2538public: 2539 StopTrackingCallback(ProgramStateRef st) : state(st) {} 2540 ProgramStateRef getState() const { return state; } 2541 2542 bool VisitSymbol(SymbolRef sym) { 2543 state = state->remove<RefBindings>(sym); 2544 return true; 2545 } 2546}; 2547} // end anonymous namespace 2548 2549//===----------------------------------------------------------------------===// 2550// Handle statements that may have an effect on refcounts. 2551//===----------------------------------------------------------------------===// 2552 2553void RetainCountChecker::checkPostStmt(const BlockExpr *BE, 2554 CheckerContext &C) const { 2555 2556 // Scan the BlockDecRefExprs for any object the retain count checker 2557 // may be tracking. 2558 if (!BE->getBlockDecl()->hasCaptures()) 2559 return; 2560 2561 ProgramStateRef state = C.getState(); 2562 const BlockDataRegion *R = 2563 cast<BlockDataRegion>(state->getSVal(BE, 2564 C.getLocationContext()).getAsRegion()); 2565 2566 BlockDataRegion::referenced_vars_iterator I = R->referenced_vars_begin(), 2567 E = R->referenced_vars_end(); 2568 2569 if (I == E) 2570 return; 2571 2572 // FIXME: For now we invalidate the tracking of all symbols passed to blocks 2573 // via captured variables, even though captured variables result in a copy 2574 // and in implicit increment/decrement of a retain count. 2575 SmallVector<const MemRegion*, 10> Regions; 2576 const LocationContext *LC = C.getLocationContext(); 2577 MemRegionManager &MemMgr = C.getSValBuilder().getRegionManager(); 2578 2579 for ( ; I != E; ++I) { 2580 const VarRegion *VR = *I; 2581 if (VR->getSuperRegion() == R) { 2582 VR = MemMgr.getVarRegion(VR->getDecl(), LC); 2583 } 2584 Regions.push_back(VR); 2585 } 2586 2587 state = 2588 state->scanReachableSymbols<StopTrackingCallback>(Regions.data(), 2589 Regions.data() + Regions.size()).getState(); 2590 C.addTransition(state); 2591} 2592 2593void RetainCountChecker::checkPostStmt(const CastExpr *CE, 2594 CheckerContext &C) const { 2595 const ObjCBridgedCastExpr *BE = dyn_cast<ObjCBridgedCastExpr>(CE); 2596 if (!BE) 2597 return; 2598 2599 ArgEffect AE = IncRef; 2600 2601 switch (BE->getBridgeKind()) { 2602 case clang::OBC_Bridge: 2603 // Do nothing. 2604 return; 2605 case clang::OBC_BridgeRetained: 2606 AE = IncRef; 2607 break; 2608 case clang::OBC_BridgeTransfer: 2609 AE = DecRefBridgedTransfered; 2610 break; 2611 } 2612 2613 ProgramStateRef state = C.getState(); 2614 SymbolRef Sym = state->getSVal(CE, C.getLocationContext()).getAsLocSymbol(); 2615 if (!Sym) 2616 return; 2617 const RefVal* T = state->get<RefBindings>(Sym); 2618 if (!T) 2619 return; 2620 2621 RefVal::Kind hasErr = (RefVal::Kind) 0; 2622 state = updateSymbol(state, Sym, *T, AE, hasErr, C); 2623 2624 if (hasErr) { 2625 // FIXME: If we get an error during a bridge cast, should we report it? 2626 // Should we assert that there is no error? 2627 return; 2628 } 2629 2630 C.addTransition(state); 2631} 2632 2633void RetainCountChecker::checkPostStmt(const CallExpr *CE, 2634 CheckerContext &C) const { 2635 // Get the callee. 2636 ProgramStateRef state = C.getState(); 2637 const Expr *Callee = CE->getCallee(); 2638 SVal L = state->getSVal(Callee, C.getLocationContext()); 2639 2640 RetainSummaryManager &Summaries = getSummaryManager(C); 2641 const RetainSummary *Summ = 0; 2642 2643 // FIXME: Better support for blocks. For now we stop tracking anything 2644 // that is passed to blocks. 2645 // FIXME: Need to handle variables that are "captured" by the block. 2646 if (dyn_cast_or_null<BlockDataRegion>(L.getAsRegion())) { 2647 Summ = Summaries.getPersistentStopSummary(); 2648 } else if (const FunctionDecl *FD = L.getAsFunctionDecl()) { 2649 Summ = Summaries.getSummary(FD); 2650 } else if (const CXXMemberCallExpr *me = dyn_cast<CXXMemberCallExpr>(CE)) { 2651 if (const CXXMethodDecl *MD = me->getMethodDecl()) 2652 Summ = Summaries.getSummary(MD); 2653 } 2654 2655 if (!Summ) 2656 Summ = Summaries.getDefaultSummary(); 2657 2658 checkSummary(*Summ, CallOrObjCMessage(CE, state, C.getLocationContext()), C); 2659} 2660 2661void RetainCountChecker::checkPostStmt(const CXXConstructExpr *CE, 2662 CheckerContext &C) const { 2663 const CXXConstructorDecl *Ctor = CE->getConstructor(); 2664 if (!Ctor) 2665 return; 2666 2667 RetainSummaryManager &Summaries = getSummaryManager(C); 2668 const RetainSummary *Summ = Summaries.getSummary(Ctor); 2669 2670 // If we didn't get a summary, this constructor doesn't affect retain counts. 2671 if (!Summ) 2672 return; 2673 2674 ProgramStateRef state = C.getState(); 2675 checkSummary(*Summ, CallOrObjCMessage(CE, state, C.getLocationContext()), C); 2676} 2677 2678void RetainCountChecker::processObjCLiterals(CheckerContext &C, 2679 const Expr *Ex) const { 2680 ProgramStateRef state = C.getState(); 2681 const ExplodedNode *pred = C.getPredecessor(); 2682 for (Stmt::const_child_iterator it = Ex->child_begin(), et = Ex->child_end() ; 2683 it != et ; ++it) { 2684 const Stmt *child = *it; 2685 SVal V = state->getSVal(child, pred->getLocationContext()); 2686 if (SymbolRef sym = V.getAsSymbol()) 2687 if (const RefVal* T = state->get<RefBindings>(sym)) { 2688 RefVal::Kind hasErr = (RefVal::Kind) 0; 2689 state = updateSymbol(state, sym, *T, MayEscape, hasErr, C); 2690 if (hasErr) { 2691 processNonLeakError(state, child->getSourceRange(), hasErr, sym, C); 2692 return; 2693 } 2694 } 2695 } 2696 2697 // Return the object as autoreleased. 2698 // RetEffect RE = RetEffect::MakeNotOwned(RetEffect::ObjC); 2699 if (SymbolRef sym = 2700 state->getSVal(Ex, pred->getLocationContext()).getAsSymbol()) { 2701 QualType ResultTy = Ex->getType(); 2702 state = state->set<RefBindings>(sym, RefVal::makeNotOwned(RetEffect::ObjC, 2703 ResultTy)); 2704 } 2705 2706 C.addTransition(state); 2707} 2708 2709void RetainCountChecker::checkPostStmt(const ObjCArrayLiteral *AL, 2710 CheckerContext &C) const { 2711 // Apply the 'MayEscape' to all values. 2712 processObjCLiterals(C, AL); 2713} 2714 2715void RetainCountChecker::checkPostStmt(const ObjCDictionaryLiteral *DL, 2716 CheckerContext &C) const { 2717 // Apply the 'MayEscape' to all keys and values. 2718 processObjCLiterals(C, DL); 2719} 2720 2721void RetainCountChecker::checkPostObjCMessage(const ObjCMessage &Msg, 2722 CheckerContext &C) const { 2723 ProgramStateRef state = C.getState(); 2724 2725 RetainSummaryManager &Summaries = getSummaryManager(C); 2726 2727 const RetainSummary *Summ; 2728 if (Msg.isInstanceMessage()) { 2729 const LocationContext *LC = C.getLocationContext(); 2730 Summ = Summaries.getInstanceMethodSummary(Msg, state, LC); 2731 } else { 2732 Summ = Summaries.getClassMethodSummary(Msg); 2733 } 2734 2735 // If we didn't get a summary, this message doesn't affect retain counts. 2736 if (!Summ) 2737 return; 2738 2739 checkSummary(*Summ, CallOrObjCMessage(Msg, state, C.getLocationContext()), C); 2740} 2741 2742/// GetReturnType - Used to get the return type of a message expression or 2743/// function call with the intention of affixing that type to a tracked symbol. 2744/// While the the return type can be queried directly from RetEx, when 2745/// invoking class methods we augment to the return type to be that of 2746/// a pointer to the class (as opposed it just being id). 2747// FIXME: We may be able to do this with related result types instead. 2748// This function is probably overestimating. 2749static QualType GetReturnType(const Expr *RetE, ASTContext &Ctx) { 2750 QualType RetTy = RetE->getType(); 2751 // If RetE is not a message expression just return its type. 2752 // If RetE is a message expression, return its types if it is something 2753 /// more specific than id. 2754 if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(RetE)) 2755 if (const ObjCObjectPointerType *PT = RetTy->getAs<ObjCObjectPointerType>()) 2756 if (PT->isObjCQualifiedIdType() || PT->isObjCIdType() || 2757 PT->isObjCClassType()) { 2758 // At this point we know the return type of the message expression is 2759 // id, id<...>, or Class. If we have an ObjCInterfaceDecl, we know this 2760 // is a call to a class method whose type we can resolve. In such 2761 // cases, promote the return type to XXX* (where XXX is the class). 2762 const ObjCInterfaceDecl *D = ME->getReceiverInterface(); 2763 return !D ? RetTy : 2764 Ctx.getObjCObjectPointerType(Ctx.getObjCInterfaceType(D)); 2765 } 2766 2767 return RetTy; 2768} 2769 2770void RetainCountChecker::checkSummary(const RetainSummary &Summ, 2771 const CallOrObjCMessage &CallOrMsg, 2772 CheckerContext &C) const { 2773 ProgramStateRef state = C.getState(); 2774 2775 // Evaluate the effect of the arguments. 2776 RefVal::Kind hasErr = (RefVal::Kind) 0; 2777 SourceRange ErrorRange; 2778 SymbolRef ErrorSym = 0; 2779 2780 for (unsigned idx = 0, e = CallOrMsg.getNumArgs(); idx != e; ++idx) { 2781 SVal V = CallOrMsg.getArgSVal(idx); 2782 2783 if (SymbolRef Sym = V.getAsLocSymbol()) { 2784 if (RefBindings::data_type *T = state->get<RefBindings>(Sym)) { 2785 state = updateSymbol(state, Sym, *T, Summ.getArg(idx), hasErr, C); 2786 if (hasErr) { 2787 ErrorRange = CallOrMsg.getArgSourceRange(idx); 2788 ErrorSym = Sym; 2789 break; 2790 } 2791 } 2792 } 2793 } 2794 2795 // Evaluate the effect on the message receiver. 2796 bool ReceiverIsTracked = false; 2797 if (!hasErr && CallOrMsg.isObjCMessage()) { 2798 const LocationContext *LC = C.getLocationContext(); 2799 SVal Receiver = CallOrMsg.getInstanceMessageReceiver(LC); 2800 if (SymbolRef Sym = Receiver.getAsLocSymbol()) { 2801 if (const RefVal *T = state->get<RefBindings>(Sym)) { 2802 ReceiverIsTracked = true; 2803 state = updateSymbol(state, Sym, *T, Summ.getReceiverEffect(), 2804 hasErr, C); 2805 if (hasErr) { 2806 ErrorRange = CallOrMsg.getReceiverSourceRange(); 2807 ErrorSym = Sym; 2808 } 2809 } 2810 } 2811 } 2812 2813 // Process any errors. 2814 if (hasErr) { 2815 processNonLeakError(state, ErrorRange, hasErr, ErrorSym, C); 2816 return; 2817 } 2818 2819 // Consult the summary for the return value. 2820 RetEffect RE = Summ.getRetEffect(); 2821 2822 if (RE.getKind() == RetEffect::OwnedWhenTrackedReceiver) { 2823 if (ReceiverIsTracked) 2824 RE = getSummaryManager(C).getObjAllocRetEffect(); 2825 else 2826 RE = RetEffect::MakeNoRet(); 2827 } 2828 2829 switch (RE.getKind()) { 2830 default: 2831 llvm_unreachable("Unhandled RetEffect."); 2832 2833 case RetEffect::NoRet: 2834 // No work necessary. 2835 break; 2836 2837 case RetEffect::OwnedAllocatedSymbol: 2838 case RetEffect::OwnedSymbol: { 2839 SymbolRef Sym = state->getSVal(CallOrMsg.getOriginExpr(), 2840 C.getLocationContext()).getAsSymbol(); 2841 if (!Sym) 2842 break; 2843 2844 // Use the result type from callOrMsg as it automatically adjusts 2845 // for methods/functions that return references. 2846 QualType ResultTy = CallOrMsg.getResultType(C.getASTContext()); 2847 state = state->set<RefBindings>(Sym, RefVal::makeOwned(RE.getObjKind(), 2848 ResultTy)); 2849 2850 // FIXME: Add a flag to the checker where allocations are assumed to 2851 // *not* fail. (The code below is out-of-date, though.) 2852#if 0 2853 if (RE.getKind() == RetEffect::OwnedAllocatedSymbol) { 2854 bool isFeasible; 2855 state = state.assume(loc::SymbolVal(Sym), true, isFeasible); 2856 assert(isFeasible && "Cannot assume fresh symbol is non-null."); 2857 } 2858#endif 2859 2860 break; 2861 } 2862 2863 case RetEffect::GCNotOwnedSymbol: 2864 case RetEffect::ARCNotOwnedSymbol: 2865 case RetEffect::NotOwnedSymbol: { 2866 const Expr *Ex = CallOrMsg.getOriginExpr(); 2867 SymbolRef Sym = state->getSVal(Ex, C.getLocationContext()).getAsSymbol(); 2868 if (!Sym) 2869 break; 2870 2871 // Use GetReturnType in order to give [NSFoo alloc] the type NSFoo *. 2872 QualType ResultTy = GetReturnType(Ex, C.getASTContext()); 2873 state = state->set<RefBindings>(Sym, RefVal::makeNotOwned(RE.getObjKind(), 2874 ResultTy)); 2875 break; 2876 } 2877 } 2878 2879 // This check is actually necessary; otherwise the statement builder thinks 2880 // we've hit a previously-found path. 2881 // Normally addTransition takes care of this, but we want the node pointer. 2882 ExplodedNode *NewNode; 2883 if (state == C.getState()) { 2884 NewNode = C.getPredecessor(); 2885 } else { 2886 NewNode = C.addTransition(state); 2887 } 2888 2889 // Annotate the node with summary we used. 2890 if (NewNode) { 2891 // FIXME: This is ugly. See checkEndAnalysis for why it's necessary. 2892 if (ShouldResetSummaryLog) { 2893 SummaryLog.clear(); 2894 ShouldResetSummaryLog = false; 2895 } 2896 SummaryLog[NewNode] = &Summ; 2897 } 2898} 2899 2900 2901ProgramStateRef 2902RetainCountChecker::updateSymbol(ProgramStateRef state, SymbolRef sym, 2903 RefVal V, ArgEffect E, RefVal::Kind &hasErr, 2904 CheckerContext &C) const { 2905 // In GC mode [... release] and [... retain] do nothing. 2906 // In ARC mode they shouldn't exist at all, but we just ignore them. 2907 bool IgnoreRetainMsg = C.isObjCGCEnabled(); 2908 if (!IgnoreRetainMsg) 2909 IgnoreRetainMsg = (bool)C.getASTContext().getLangOpts().ObjCAutoRefCount; 2910 2911 switch (E) { 2912 default: break; 2913 case IncRefMsg: E = IgnoreRetainMsg ? DoNothing : IncRef; break; 2914 case DecRefMsg: E = IgnoreRetainMsg ? DoNothing : DecRef; break; 2915 case MakeCollectable: E = C.isObjCGCEnabled() ? DecRef : DoNothing; break; 2916 case NewAutoreleasePool: E = C.isObjCGCEnabled() ? DoNothing : 2917 NewAutoreleasePool; break; 2918 } 2919 2920 // Handle all use-after-releases. 2921 if (!C.isObjCGCEnabled() && V.getKind() == RefVal::Released) { 2922 V = V ^ RefVal::ErrorUseAfterRelease; 2923 hasErr = V.getKind(); 2924 return state->set<RefBindings>(sym, V); 2925 } 2926 2927 switch (E) { 2928 case DecRefMsg: 2929 case IncRefMsg: 2930 case MakeCollectable: 2931 llvm_unreachable("DecRefMsg/IncRefMsg/MakeCollectable already converted"); 2932 2933 case Dealloc: 2934 // Any use of -dealloc in GC is *bad*. 2935 if (C.isObjCGCEnabled()) { 2936 V = V ^ RefVal::ErrorDeallocGC; 2937 hasErr = V.getKind(); 2938 break; 2939 } 2940 2941 switch (V.getKind()) { 2942 default: 2943 llvm_unreachable("Invalid RefVal state for an explicit dealloc."); 2944 case RefVal::Owned: 2945 // The object immediately transitions to the released state. 2946 V = V ^ RefVal::Released; 2947 V.clearCounts(); 2948 return state->set<RefBindings>(sym, V); 2949 case RefVal::NotOwned: 2950 V = V ^ RefVal::ErrorDeallocNotOwned; 2951 hasErr = V.getKind(); 2952 break; 2953 } 2954 break; 2955 2956 case NewAutoreleasePool: 2957 assert(!C.isObjCGCEnabled()); 2958 return state->add<AutoreleaseStack>(sym); 2959 2960 case MayEscape: 2961 if (V.getKind() == RefVal::Owned) { 2962 V = V ^ RefVal::NotOwned; 2963 break; 2964 } 2965 2966 // Fall-through. 2967 2968 case DoNothing: 2969 return state; 2970 2971 case Autorelease: 2972 if (C.isObjCGCEnabled()) 2973 return state; 2974 2975 // Update the autorelease counts. 2976 state = SendAutorelease(state, ARCountFactory, sym); 2977 V = V.autorelease(); 2978 break; 2979 2980 case StopTracking: 2981 return state->remove<RefBindings>(sym); 2982 2983 case IncRef: 2984 switch (V.getKind()) { 2985 default: 2986 llvm_unreachable("Invalid RefVal state for a retain."); 2987 case RefVal::Owned: 2988 case RefVal::NotOwned: 2989 V = V + 1; 2990 break; 2991 case RefVal::Released: 2992 // Non-GC cases are handled above. 2993 assert(C.isObjCGCEnabled()); 2994 V = (V ^ RefVal::Owned) + 1; 2995 break; 2996 } 2997 break; 2998 2999 case SelfOwn: 3000 V = V ^ RefVal::NotOwned; 3001 // Fall-through. 3002 case DecRef: 3003 case DecRefBridgedTransfered: 3004 switch (V.getKind()) { 3005 default: 3006 // case 'RefVal::Released' handled above. 3007 llvm_unreachable("Invalid RefVal state for a release."); 3008 3009 case RefVal::Owned: 3010 assert(V.getCount() > 0); 3011 if (V.getCount() == 1) 3012 V = V ^ (E == DecRefBridgedTransfered ? 3013 RefVal::NotOwned : RefVal::Released); 3014 V = V - 1; 3015 break; 3016 3017 case RefVal::NotOwned: 3018 if (V.getCount() > 0) 3019 V = V - 1; 3020 else { 3021 V = V ^ RefVal::ErrorReleaseNotOwned; 3022 hasErr = V.getKind(); 3023 } 3024 break; 3025 3026 case RefVal::Released: 3027 // Non-GC cases are handled above. 3028 assert(C.isObjCGCEnabled()); 3029 V = V ^ RefVal::ErrorUseAfterRelease; 3030 hasErr = V.getKind(); 3031 break; 3032 } 3033 break; 3034 } 3035 return state->set<RefBindings>(sym, V); 3036} 3037 3038void RetainCountChecker::processNonLeakError(ProgramStateRef St, 3039 SourceRange ErrorRange, 3040 RefVal::Kind ErrorKind, 3041 SymbolRef Sym, 3042 CheckerContext &C) const { 3043 ExplodedNode *N = C.generateSink(St); 3044 if (!N) 3045 return; 3046 3047 CFRefBug *BT; 3048 switch (ErrorKind) { 3049 default: 3050 llvm_unreachable("Unhandled error."); 3051 case RefVal::ErrorUseAfterRelease: 3052 if (!useAfterRelease) 3053 useAfterRelease.reset(new UseAfterRelease()); 3054 BT = &*useAfterRelease; 3055 break; 3056 case RefVal::ErrorReleaseNotOwned: 3057 if (!releaseNotOwned) 3058 releaseNotOwned.reset(new BadRelease()); 3059 BT = &*releaseNotOwned; 3060 break; 3061 case RefVal::ErrorDeallocGC: 3062 if (!deallocGC) 3063 deallocGC.reset(new DeallocGC()); 3064 BT = &*deallocGC; 3065 break; 3066 case RefVal::ErrorDeallocNotOwned: 3067 if (!deallocNotOwned) 3068 deallocNotOwned.reset(new DeallocNotOwned()); 3069 BT = &*deallocNotOwned; 3070 break; 3071 } 3072 3073 assert(BT); 3074 CFRefReport *report = new CFRefReport(*BT, C.getASTContext().getLangOpts(), 3075 C.isObjCGCEnabled(), SummaryLog, 3076 N, Sym); 3077 report->addRange(ErrorRange); 3078 C.EmitReport(report); 3079} 3080 3081//===----------------------------------------------------------------------===// 3082// Handle the return values of retain-count-related functions. 3083//===----------------------------------------------------------------------===// 3084 3085bool RetainCountChecker::evalCall(const CallExpr *CE, CheckerContext &C) const { 3086 // Get the callee. We're only interested in simple C functions. 3087 ProgramStateRef state = C.getState(); 3088 const FunctionDecl *FD = C.getCalleeDecl(CE); 3089 if (!FD) 3090 return false; 3091 3092 IdentifierInfo *II = FD->getIdentifier(); 3093 if (!II) 3094 return false; 3095 3096 // For now, we're only handling the functions that return aliases of their 3097 // arguments: CFRetain and CFMakeCollectable (and their families). 3098 // Eventually we should add other functions we can model entirely, 3099 // such as CFRelease, which don't invalidate their arguments or globals. 3100 if (CE->getNumArgs() != 1) 3101 return false; 3102 3103 // Get the name of the function. 3104 StringRef FName = II->getName(); 3105 FName = FName.substr(FName.find_first_not_of('_')); 3106 3107 // See if it's one of the specific functions we know how to eval. 3108 bool canEval = false; 3109 3110 QualType ResultTy = CE->getCallReturnType(); 3111 if (ResultTy->isObjCIdType()) { 3112 // Handle: id NSMakeCollectable(CFTypeRef) 3113 canEval = II->isStr("NSMakeCollectable"); 3114 } else if (ResultTy->isPointerType()) { 3115 // Handle: (CF|CG)Retain 3116 // CFMakeCollectable 3117 // It's okay to be a little sloppy here (CGMakeCollectable doesn't exist). 3118 if (cocoa::isRefType(ResultTy, "CF", FName) || 3119 cocoa::isRefType(ResultTy, "CG", FName)) { 3120 canEval = isRetain(FD, FName) || isMakeCollectable(FD, FName); 3121 } 3122 } 3123 3124 if (!canEval) 3125 return false; 3126 3127 // Bind the return value. 3128 const LocationContext *LCtx = C.getLocationContext(); 3129 SVal RetVal = state->getSVal(CE->getArg(0), LCtx); 3130 if (RetVal.isUnknown()) { 3131 // If the receiver is unknown, conjure a return value. 3132 SValBuilder &SVB = C.getSValBuilder(); 3133 unsigned Count = C.getCurrentBlockCount(); 3134 SVal RetVal = SVB.getConjuredSymbolVal(0, CE, LCtx, ResultTy, Count); 3135 } 3136 state = state->BindExpr(CE, LCtx, RetVal, false); 3137 3138 // FIXME: This should not be necessary, but otherwise the argument seems to be 3139 // considered alive during the next statement. 3140 if (const MemRegion *ArgRegion = RetVal.getAsRegion()) { 3141 // Save the refcount status of the argument. 3142 SymbolRef Sym = RetVal.getAsLocSymbol(); 3143 RefBindings::data_type *Binding = 0; 3144 if (Sym) 3145 Binding = state->get<RefBindings>(Sym); 3146 3147 // Invalidate the argument region. 3148 unsigned Count = C.getCurrentBlockCount(); 3149 state = state->invalidateRegions(ArgRegion, CE, Count, LCtx); 3150 3151 // Restore the refcount status of the argument. 3152 if (Binding) 3153 state = state->set<RefBindings>(Sym, *Binding); 3154 } 3155 3156 C.addTransition(state); 3157 return true; 3158} 3159 3160//===----------------------------------------------------------------------===// 3161// Handle return statements. 3162//===----------------------------------------------------------------------===// 3163 3164// Return true if the current LocationContext has no caller context. 3165static bool inTopFrame(CheckerContext &C) { 3166 const LocationContext *LC = C.getLocationContext(); 3167 return LC->getParent() == 0; 3168} 3169 3170void RetainCountChecker::checkPreStmt(const ReturnStmt *S, 3171 CheckerContext &C) const { 3172 3173 // Only adjust the reference count if this is the top-level call frame, 3174 // and not the result of inlining. In the future, we should do 3175 // better checking even for inlined calls, and see if they match 3176 // with their expected semantics (e.g., the method should return a retained 3177 // object, etc.). 3178 if (!inTopFrame(C)) 3179 return; 3180 3181 const Expr *RetE = S->getRetValue(); 3182 if (!RetE) 3183 return; 3184 3185 ProgramStateRef state = C.getState(); 3186 SymbolRef Sym = 3187 state->getSValAsScalarOrLoc(RetE, C.getLocationContext()).getAsLocSymbol(); 3188 if (!Sym) 3189 return; 3190 3191 // Get the reference count binding (if any). 3192 const RefVal *T = state->get<RefBindings>(Sym); 3193 if (!T) 3194 return; 3195 3196 // Change the reference count. 3197 RefVal X = *T; 3198 3199 switch (X.getKind()) { 3200 case RefVal::Owned: { 3201 unsigned cnt = X.getCount(); 3202 assert(cnt > 0); 3203 X.setCount(cnt - 1); 3204 X = X ^ RefVal::ReturnedOwned; 3205 break; 3206 } 3207 3208 case RefVal::NotOwned: { 3209 unsigned cnt = X.getCount(); 3210 if (cnt) { 3211 X.setCount(cnt - 1); 3212 X = X ^ RefVal::ReturnedOwned; 3213 } 3214 else { 3215 X = X ^ RefVal::ReturnedNotOwned; 3216 } 3217 break; 3218 } 3219 3220 default: 3221 return; 3222 } 3223 3224 // Update the binding. 3225 state = state->set<RefBindings>(Sym, X); 3226 ExplodedNode *Pred = C.addTransition(state); 3227 3228 // At this point we have updated the state properly. 3229 // Everything after this is merely checking to see if the return value has 3230 // been over- or under-retained. 3231 3232 // Did we cache out? 3233 if (!Pred) 3234 return; 3235 3236 // Update the autorelease counts. 3237 static SimpleProgramPointTag 3238 AutoreleaseTag("RetainCountChecker : Autorelease"); 3239 GenericNodeBuilderRefCount Bd(C, &AutoreleaseTag); 3240 llvm::tie(Pred, state) = handleAutoreleaseCounts(state, Bd, Pred, C, Sym, X); 3241 3242 // Did we cache out? 3243 if (!Pred) 3244 return; 3245 3246 // Get the updated binding. 3247 T = state->get<RefBindings>(Sym); 3248 assert(T); 3249 X = *T; 3250 3251 // Consult the summary of the enclosing method. 3252 RetainSummaryManager &Summaries = getSummaryManager(C); 3253 const Decl *CD = &Pred->getCodeDecl(); 3254 3255 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(CD)) { 3256 // Unlike regular functions, /all/ ObjC methods are assumed to always 3257 // follow Cocoa retain-count conventions, not just those with special 3258 // names or attributes. 3259 const RetainSummary *Summ = Summaries.getMethodSummary(MD); 3260 RetEffect RE = Summ ? Summ->getRetEffect() : RetEffect::MakeNoRet(); 3261 checkReturnWithRetEffect(S, C, Pred, RE, X, Sym, state); 3262 } 3263 3264 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CD)) { 3265 if (!isa<CXXMethodDecl>(FD)) 3266 if (const RetainSummary *Summ = Summaries.getSummary(FD)) 3267 checkReturnWithRetEffect(S, C, Pred, Summ->getRetEffect(), X, 3268 Sym, state); 3269 } 3270} 3271 3272void RetainCountChecker::checkReturnWithRetEffect(const ReturnStmt *S, 3273 CheckerContext &C, 3274 ExplodedNode *Pred, 3275 RetEffect RE, RefVal X, 3276 SymbolRef Sym, 3277 ProgramStateRef state) const { 3278 // Any leaks or other errors? 3279 if (X.isReturnedOwned() && X.getCount() == 0) { 3280 if (RE.getKind() != RetEffect::NoRet) { 3281 bool hasError = false; 3282 if (C.isObjCGCEnabled() && RE.getObjKind() == RetEffect::ObjC) { 3283 // Things are more complicated with garbage collection. If the 3284 // returned object is suppose to be an Objective-C object, we have 3285 // a leak (as the caller expects a GC'ed object) because no 3286 // method should return ownership unless it returns a CF object. 3287 hasError = true; 3288 X = X ^ RefVal::ErrorGCLeakReturned; 3289 } 3290 else if (!RE.isOwned()) { 3291 // Either we are using GC and the returned object is a CF type 3292 // or we aren't using GC. In either case, we expect that the 3293 // enclosing method is expected to return ownership. 3294 hasError = true; 3295 X = X ^ RefVal::ErrorLeakReturned; 3296 } 3297 3298 if (hasError) { 3299 // Generate an error node. 3300 state = state->set<RefBindings>(Sym, X); 3301 3302 static SimpleProgramPointTag 3303 ReturnOwnLeakTag("RetainCountChecker : ReturnsOwnLeak"); 3304 ExplodedNode *N = C.addTransition(state, Pred, &ReturnOwnLeakTag); 3305 if (N) { 3306 const LangOptions &LOpts = C.getASTContext().getLangOpts(); 3307 bool GCEnabled = C.isObjCGCEnabled(); 3308 CFRefReport *report = 3309 new CFRefLeakReport(*getLeakAtReturnBug(LOpts, GCEnabled), 3310 LOpts, GCEnabled, SummaryLog, 3311 N, Sym, C); 3312 C.EmitReport(report); 3313 } 3314 } 3315 } 3316 } else if (X.isReturnedNotOwned()) { 3317 if (RE.isOwned()) { 3318 // Trying to return a not owned object to a caller expecting an 3319 // owned object. 3320 state = state->set<RefBindings>(Sym, X ^ RefVal::ErrorReturnedNotOwned); 3321 3322 static SimpleProgramPointTag 3323 ReturnNotOwnedTag("RetainCountChecker : ReturnNotOwnedForOwned"); 3324 ExplodedNode *N = C.addTransition(state, Pred, &ReturnNotOwnedTag); 3325 if (N) { 3326 if (!returnNotOwnedForOwned) 3327 returnNotOwnedForOwned.reset(new ReturnedNotOwnedForOwned()); 3328 3329 CFRefReport *report = 3330 new CFRefReport(*returnNotOwnedForOwned, 3331 C.getASTContext().getLangOpts(), 3332 C.isObjCGCEnabled(), SummaryLog, N, Sym); 3333 C.EmitReport(report); 3334 } 3335 } 3336 } 3337} 3338 3339//===----------------------------------------------------------------------===// 3340// Check various ways a symbol can be invalidated. 3341//===----------------------------------------------------------------------===// 3342 3343void RetainCountChecker::checkBind(SVal loc, SVal val, const Stmt *S, 3344 CheckerContext &C) const { 3345 // Are we storing to something that causes the value to "escape"? 3346 bool escapes = true; 3347 3348 // A value escapes in three possible cases (this may change): 3349 // 3350 // (1) we are binding to something that is not a memory region. 3351 // (2) we are binding to a memregion that does not have stack storage 3352 // (3) we are binding to a memregion with stack storage that the store 3353 // does not understand. 3354 ProgramStateRef state = C.getState(); 3355 3356 if (loc::MemRegionVal *regionLoc = dyn_cast<loc::MemRegionVal>(&loc)) { 3357 escapes = !regionLoc->getRegion()->hasStackStorage(); 3358 3359 if (!escapes) { 3360 // To test (3), generate a new state with the binding added. If it is 3361 // the same state, then it escapes (since the store cannot represent 3362 // the binding). 3363 escapes = (state == (state->bindLoc(*regionLoc, val))); 3364 } 3365 } 3366 3367 // If our store can represent the binding and we aren't storing to something 3368 // that doesn't have local storage then just return and have the simulation 3369 // state continue as is. 3370 if (!escapes) 3371 return; 3372 3373 // Otherwise, find all symbols referenced by 'val' that we are tracking 3374 // and stop tracking them. 3375 state = state->scanReachableSymbols<StopTrackingCallback>(val).getState(); 3376 C.addTransition(state); 3377} 3378 3379ProgramStateRef RetainCountChecker::evalAssume(ProgramStateRef state, 3380 SVal Cond, 3381 bool Assumption) const { 3382 3383 // FIXME: We may add to the interface of evalAssume the list of symbols 3384 // whose assumptions have changed. For now we just iterate through the 3385 // bindings and check if any of the tracked symbols are NULL. This isn't 3386 // too bad since the number of symbols we will track in practice are 3387 // probably small and evalAssume is only called at branches and a few 3388 // other places. 3389 RefBindings B = state->get<RefBindings>(); 3390 3391 if (B.isEmpty()) 3392 return state; 3393 3394 bool changed = false; 3395 RefBindings::Factory &RefBFactory = state->get_context<RefBindings>(); 3396 3397 for (RefBindings::iterator I = B.begin(), E = B.end(); I != E; ++I) { 3398 // Check if the symbol is null (or equal to any constant). 3399 // If this is the case, stop tracking the symbol. 3400 if (state->getSymVal(I.getKey())) { 3401 changed = true; 3402 B = RefBFactory.remove(B, I.getKey()); 3403 } 3404 } 3405 3406 if (changed) 3407 state = state->set<RefBindings>(B); 3408 3409 return state; 3410} 3411 3412ProgramStateRef 3413RetainCountChecker::checkRegionChanges(ProgramStateRef state, 3414 const StoreManager::InvalidatedSymbols *invalidated, 3415 ArrayRef<const MemRegion *> ExplicitRegions, 3416 ArrayRef<const MemRegion *> Regions, 3417 const CallOrObjCMessage *Call) const { 3418 if (!invalidated) 3419 return state; 3420 3421 llvm::SmallPtrSet<SymbolRef, 8> WhitelistedSymbols; 3422 for (ArrayRef<const MemRegion *>::iterator I = ExplicitRegions.begin(), 3423 E = ExplicitRegions.end(); I != E; ++I) { 3424 if (const SymbolicRegion *SR = (*I)->StripCasts()->getAs<SymbolicRegion>()) 3425 WhitelistedSymbols.insert(SR->getSymbol()); 3426 } 3427 3428 for (StoreManager::InvalidatedSymbols::const_iterator I=invalidated->begin(), 3429 E = invalidated->end(); I!=E; ++I) { 3430 SymbolRef sym = *I; 3431 if (WhitelistedSymbols.count(sym)) 3432 continue; 3433 // Remove any existing reference-count binding. 3434 state = state->remove<RefBindings>(sym); 3435 } 3436 return state; 3437} 3438 3439//===----------------------------------------------------------------------===// 3440// Handle dead symbols and end-of-path. 3441//===----------------------------------------------------------------------===// 3442 3443std::pair<ExplodedNode *, ProgramStateRef > 3444RetainCountChecker::handleAutoreleaseCounts(ProgramStateRef state, 3445 GenericNodeBuilderRefCount Bd, 3446 ExplodedNode *Pred, 3447 CheckerContext &Ctx, 3448 SymbolRef Sym, RefVal V) const { 3449 unsigned ACnt = V.getAutoreleaseCount(); 3450 3451 // No autorelease counts? Nothing to be done. 3452 if (!ACnt) 3453 return std::make_pair(Pred, state); 3454 3455 assert(!Ctx.isObjCGCEnabled() && "Autorelease counts in GC mode?"); 3456 unsigned Cnt = V.getCount(); 3457 3458 // FIXME: Handle sending 'autorelease' to already released object. 3459 3460 if (V.getKind() == RefVal::ReturnedOwned) 3461 ++Cnt; 3462 3463 if (ACnt <= Cnt) { 3464 if (ACnt == Cnt) { 3465 V.clearCounts(); 3466 if (V.getKind() == RefVal::ReturnedOwned) 3467 V = V ^ RefVal::ReturnedNotOwned; 3468 else 3469 V = V ^ RefVal::NotOwned; 3470 } else { 3471 V.setCount(Cnt - ACnt); 3472 V.setAutoreleaseCount(0); 3473 } 3474 state = state->set<RefBindings>(Sym, V); 3475 ExplodedNode *N = Bd.MakeNode(state, Pred); 3476 if (N == 0) 3477 state = 0; 3478 return std::make_pair(N, state); 3479 } 3480 3481 // Woah! More autorelease counts then retain counts left. 3482 // Emit hard error. 3483 V = V ^ RefVal::ErrorOverAutorelease; 3484 state = state->set<RefBindings>(Sym, V); 3485 3486 if (ExplodedNode *N = Bd.MakeNode(state, Pred, true)) { 3487 SmallString<128> sbuf; 3488 llvm::raw_svector_ostream os(sbuf); 3489 os << "Object over-autoreleased: object was sent -autorelease "; 3490 if (V.getAutoreleaseCount() > 1) 3491 os << V.getAutoreleaseCount() << " times "; 3492 os << "but the object has a +" << V.getCount() << " retain count"; 3493 3494 if (!overAutorelease) 3495 overAutorelease.reset(new OverAutorelease()); 3496 3497 const LangOptions &LOpts = Ctx.getASTContext().getLangOpts(); 3498 CFRefReport *report = 3499 new CFRefReport(*overAutorelease, LOpts, /* GCEnabled = */ false, 3500 SummaryLog, N, Sym, os.str()); 3501 Ctx.EmitReport(report); 3502 } 3503 3504 return std::make_pair((ExplodedNode *)0, (ProgramStateRef )0); 3505} 3506 3507ProgramStateRef 3508RetainCountChecker::handleSymbolDeath(ProgramStateRef state, 3509 SymbolRef sid, RefVal V, 3510 SmallVectorImpl<SymbolRef> &Leaked) const { 3511 bool hasLeak = false; 3512 if (V.isOwned()) 3513 hasLeak = true; 3514 else if (V.isNotOwned() || V.isReturnedOwned()) 3515 hasLeak = (V.getCount() > 0); 3516 3517 if (!hasLeak) 3518 return state->remove<RefBindings>(sid); 3519 3520 Leaked.push_back(sid); 3521 return state->set<RefBindings>(sid, V ^ RefVal::ErrorLeak); 3522} 3523 3524ExplodedNode * 3525RetainCountChecker::processLeaks(ProgramStateRef state, 3526 SmallVectorImpl<SymbolRef> &Leaked, 3527 GenericNodeBuilderRefCount &Builder, 3528 CheckerContext &Ctx, 3529 ExplodedNode *Pred) const { 3530 if (Leaked.empty()) 3531 return Pred; 3532 3533 // Generate an intermediate node representing the leak point. 3534 ExplodedNode *N = Builder.MakeNode(state, Pred); 3535 3536 if (N) { 3537 for (SmallVectorImpl<SymbolRef>::iterator 3538 I = Leaked.begin(), E = Leaked.end(); I != E; ++I) { 3539 3540 const LangOptions &LOpts = Ctx.getASTContext().getLangOpts(); 3541 bool GCEnabled = Ctx.isObjCGCEnabled(); 3542 CFRefBug *BT = Pred ? getLeakWithinFunctionBug(LOpts, GCEnabled) 3543 : getLeakAtReturnBug(LOpts, GCEnabled); 3544 assert(BT && "BugType not initialized."); 3545 3546 CFRefLeakReport *report = new CFRefLeakReport(*BT, LOpts, GCEnabled, 3547 SummaryLog, N, *I, Ctx); 3548 Ctx.EmitReport(report); 3549 } 3550 } 3551 3552 return N; 3553} 3554 3555void RetainCountChecker::checkEndPath(CheckerContext &Ctx) const { 3556 ProgramStateRef state = Ctx.getState(); 3557 GenericNodeBuilderRefCount Bd(Ctx); 3558 RefBindings B = state->get<RefBindings>(); 3559 ExplodedNode *Pred = Ctx.getPredecessor(); 3560 3561 for (RefBindings::iterator I = B.begin(), E = B.end(); I != E; ++I) { 3562 llvm::tie(Pred, state) = handleAutoreleaseCounts(state, Bd, Pred, Ctx, 3563 I->first, I->second); 3564 if (!state) 3565 return; 3566 } 3567 3568 // If the current LocationContext has a parent, don't check for leaks. 3569 // We will do that later. 3570 // FIXME: we should instead check for imblances of the retain/releases, 3571 // and suggest annotations. 3572 if (Ctx.getLocationContext()->getParent()) 3573 return; 3574 3575 B = state->get<RefBindings>(); 3576 SmallVector<SymbolRef, 10> Leaked; 3577 3578 for (RefBindings::iterator I = B.begin(), E = B.end(); I != E; ++I) 3579 state = handleSymbolDeath(state, I->first, I->second, Leaked); 3580 3581 processLeaks(state, Leaked, Bd, Ctx, Pred); 3582} 3583 3584const ProgramPointTag * 3585RetainCountChecker::getDeadSymbolTag(SymbolRef sym) const { 3586 const SimpleProgramPointTag *&tag = DeadSymbolTags[sym]; 3587 if (!tag) { 3588 SmallString<64> buf; 3589 llvm::raw_svector_ostream out(buf); 3590 out << "RetainCountChecker : Dead Symbol : "; 3591 sym->dumpToStream(out); 3592 tag = new SimpleProgramPointTag(out.str()); 3593 } 3594 return tag; 3595} 3596 3597void RetainCountChecker::checkDeadSymbols(SymbolReaper &SymReaper, 3598 CheckerContext &C) const { 3599 ExplodedNode *Pred = C.getPredecessor(); 3600 3601 ProgramStateRef state = C.getState(); 3602 RefBindings B = state->get<RefBindings>(); 3603 3604 // Update counts from autorelease pools 3605 for (SymbolReaper::dead_iterator I = SymReaper.dead_begin(), 3606 E = SymReaper.dead_end(); I != E; ++I) { 3607 SymbolRef Sym = *I; 3608 if (const RefVal *T = B.lookup(Sym)){ 3609 // Use the symbol as the tag. 3610 // FIXME: This might not be as unique as we would like. 3611 GenericNodeBuilderRefCount Bd(C, getDeadSymbolTag(Sym)); 3612 llvm::tie(Pred, state) = handleAutoreleaseCounts(state, Bd, Pred, C, 3613 Sym, *T); 3614 if (!state) 3615 return; 3616 } 3617 } 3618 3619 B = state->get<RefBindings>(); 3620 SmallVector<SymbolRef, 10> Leaked; 3621 3622 for (SymbolReaper::dead_iterator I = SymReaper.dead_begin(), 3623 E = SymReaper.dead_end(); I != E; ++I) { 3624 if (const RefVal *T = B.lookup(*I)) 3625 state = handleSymbolDeath(state, *I, *T, Leaked); 3626 } 3627 3628 { 3629 GenericNodeBuilderRefCount Bd(C, this); 3630 Pred = processLeaks(state, Leaked, Bd, C, Pred); 3631 } 3632 3633 // Did we cache out? 3634 if (!Pred) 3635 return; 3636 3637 // Now generate a new node that nukes the old bindings. 3638 RefBindings::Factory &F = state->get_context<RefBindings>(); 3639 3640 for (SymbolReaper::dead_iterator I = SymReaper.dead_begin(), 3641 E = SymReaper.dead_end(); I != E; ++I) 3642 B = F.remove(B, *I); 3643 3644 state = state->set<RefBindings>(B); 3645 C.addTransition(state, Pred); 3646} 3647 3648//===----------------------------------------------------------------------===// 3649// Debug printing of refcount bindings and autorelease pools. 3650//===----------------------------------------------------------------------===// 3651 3652static void PrintPool(raw_ostream &Out, SymbolRef Sym, 3653 ProgramStateRef State) { 3654 Out << ' '; 3655 if (Sym) 3656 Sym->dumpToStream(Out); 3657 else 3658 Out << "<pool>"; 3659 Out << ":{"; 3660 3661 // Get the contents of the pool. 3662 if (const ARCounts *Cnts = State->get<AutoreleasePoolContents>(Sym)) 3663 for (ARCounts::iterator I = Cnts->begin(), E = Cnts->end(); I != E; ++I) 3664 Out << '(' << I.getKey() << ',' << I.getData() << ')'; 3665 3666 Out << '}'; 3667} 3668 3669static bool UsesAutorelease(ProgramStateRef state) { 3670 // A state uses autorelease if it allocated an autorelease pool or if it has 3671 // objects in the caller's autorelease pool. 3672 return !state->get<AutoreleaseStack>().isEmpty() || 3673 state->get<AutoreleasePoolContents>(SymbolRef()); 3674} 3675 3676void RetainCountChecker::printState(raw_ostream &Out, ProgramStateRef State, 3677 const char *NL, const char *Sep) const { 3678 3679 RefBindings B = State->get<RefBindings>(); 3680 3681 if (!B.isEmpty()) 3682 Out << Sep << NL; 3683 3684 for (RefBindings::iterator I = B.begin(), E = B.end(); I != E; ++I) { 3685 Out << I->first << " : "; 3686 I->second.print(Out); 3687 Out << NL; 3688 } 3689 3690 // Print the autorelease stack. 3691 if (UsesAutorelease(State)) { 3692 Out << Sep << NL << "AR pool stack:"; 3693 ARStack Stack = State->get<AutoreleaseStack>(); 3694 3695 PrintPool(Out, SymbolRef(), State); // Print the caller's pool. 3696 for (ARStack::iterator I = Stack.begin(), E = Stack.end(); I != E; ++I) 3697 PrintPool(Out, *I, State); 3698 3699 Out << NL; 3700 } 3701} 3702 3703//===----------------------------------------------------------------------===// 3704// Checker registration. 3705//===----------------------------------------------------------------------===// 3706 3707void ento::registerRetainCountChecker(CheckerManager &Mgr) { 3708 Mgr.registerChecker<RetainCountChecker>(); 3709} 3710 3711