ProgramState.cpp revision 314564
1139823Simp//= ProgramState.cpp - Path-Sensitive "State" for tracking values --*- C++ -*--= 211150Swollman// 31541Srgrimes// The LLVM Compiler Infrastructure 41541Srgrimes// 51541Srgrimes// This file is distributed under the University of Illinois Open Source 61541Srgrimes// License. See LICENSE.TXT for details. 71541Srgrimes// 81541Srgrimes//===----------------------------------------------------------------------===// 91541Srgrimes// 101541Srgrimes// This file implements ProgramState and ProgramStateManager. 111541Srgrimes// 121541Srgrimes//===----------------------------------------------------------------------===// 131541Srgrimes 141541Srgrimes#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h" 151541Srgrimes#include "clang/Analysis/CFG.h" 161541Srgrimes#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" 171541Srgrimes#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h" 181541Srgrimes#include "clang/StaticAnalyzer/Core/PathSensitive/SubEngine.h" 191541Srgrimes#include "clang/StaticAnalyzer/Core/PathSensitive/TaintManager.h" 201541Srgrimes#include "llvm/Support/raw_ostream.h" 211541Srgrimes 221541Srgrimesusing namespace clang; 231541Srgrimesusing namespace ento; 241541Srgrimes 251541Srgrimesnamespace clang { namespace ento { 261541Srgrimes/// Increments the number of times this state is referenced. 271541Srgrimes 281541Srgrimesvoid ProgramStateRetain(const ProgramState *state) { 2911150Swollman ++const_cast<ProgramState*>(state)->refCount; 3050477Speter} 311541Srgrimes 321541Srgrimes/// Decrement the number of times this state is referenced. 33125680Sbmsvoid ProgramStateRelease(const ProgramState *state) { 3454263Sshin assert(state->refCount > 0); 35101106Srwatson ProgramState *s = const_cast<ProgramState*>(state); 3629514Sjoerg if (--s->refCount == 0) { 3729514Sjoerg ProgramStateManager &Mgr = s->getStateManager(); 381541Srgrimes Mgr.StateSet.RemoveNode(s); 391541Srgrimes s->~ProgramState(); 4050673Sjlemon Mgr.freeStates.push_back(s); 4112172Sphk } 4212172Sphk} 431541Srgrimes}} 441541Srgrimes 45164033SrwatsonProgramState::ProgramState(ProgramStateManager *mgr, const Environment& env, 4648758Sgreen StoreRef st, GenericDataMap gdm) 471541Srgrimes : stateMgr(mgr), 481541Srgrimes Env(env), 491541Srgrimes store(st.getStore()), 5075619Skris GDM(gdm), 5134923Sbde refCount(0) { 5292760Sjeff stateMgr->getStoreManager().incrementReferenceCount(store); 531541Srgrimes} 541541Srgrimes 551541SrgrimesProgramState::ProgramState(const ProgramState &RHS) 561541Srgrimes : llvm::FoldingSetNode(), 571541Srgrimes stateMgr(RHS.stateMgr), 581541Srgrimes Env(RHS.Env), 591541Srgrimes store(RHS.store), 6055679Sshin GDM(RHS.GDM), 6155679Sshin refCount(0) { 6255679Sshin stateMgr->getStoreManager().incrementReferenceCount(store); 631541Srgrimes} 6455679Sshin 6555679SshinProgramState::~ProgramState() { 6655679Sshin if (store) 677090Sbde stateMgr->getStoreManager().decrementReferenceCount(store); 681541Srgrimes} 6955679Sshin 7055679SshinProgramStateManager::ProgramStateManager(ASTContext &Ctx, 71148385Sume StoreManagerCreator CreateSMgr, 72122922Sandre ConstraintManagerCreator CreateCMgr, 7355679Sshin llvm::BumpPtrAllocator &alloc, 74145360Sandre SubEngine *SubEng) 751541Srgrimes : Eng(SubEng), EnvMgr(alloc), GDMFactory(alloc), 761541Srgrimes svalBuilder(createSimpleSValBuilder(alloc, Ctx, *this)), 771541Srgrimes CallEventMgr(new CallEventManager(alloc)), Alloc(alloc) { 781541Srgrimes StoreMgr = (*CreateSMgr)(*this); 791541Srgrimes ConstraintMgr = (*CreateCMgr)(*this, SubEng); 8055679Sshin} 8155679Sshin 8255679Sshin 831541SrgrimesProgramStateManager::~ProgramStateManager() { 846283Swollman for (GDMContextsTy::iterator I=GDMContexts.begin(), E=GDMContexts.end(); 856283Swollman I!=E; ++I) 866283Swollman I->second.second(I->second.first); 8755679Sshin} 881541Srgrimes 8958698SjlemonProgramStateRef 9058698SjlemonProgramStateManager::removeDeadBindings(ProgramStateRef state, 91163606Srwatson const StackFrameContext *LCtx, 92163606Srwatson SymbolReaper& SymReaper) { 93162035Sglebius 94157478Sglebius // This code essentially performs a "mark-and-sweep" of the VariableBindings. 95162767Ssilby // The roots are any Block-level exprs and Decls that our liveness algorithm 96169608Sandre // tells us are live. We then see what Decls they may reference, and keep 97169608Sandre // those around. This code more than likely can be made faster, and the 98169608Sandre // frequency of which this method is called should be experimented with 99169608Sandre // for optimum performance. 100169608Sandre ProgramState NewState = *state; 101169608Sandre 102169608Sandre NewState.Env = EnvMgr.removeDeadBindings(NewState.Env, SymReaper, state); 103169608Sandre 104169608Sandre // Clean up the store. 105169608Sandre StoreRef newStore = StoreMgr->removeDeadBindings(NewState.getStore(), LCtx, 106169608Sandre SymReaper); 107162031Sglebius NewState.setStore(newStore); 108162767Ssilby SymReaper.setReapedStore(newStore); 109162767Ssilby 110162767Ssilby ProgramStateRef Result = getPersistentState(NewState); 111162767Ssilby return ConstraintMgr->removeDeadBindings(Result, SymReaper); 112162767Ssilby} 113162768Smaxim 114162768SmaximProgramStateRef ProgramState::bindLoc(Loc LV, SVal V, bool notifyChanges) const { 115162768Smaxim ProgramStateManager &Mgr = getStateManager(); 116162767Ssilby ProgramStateRef newState = makeWithStore(Mgr.StoreMgr->Bind(getStore(), 117162767Ssilby LV, V)); 118162767Ssilby const MemRegion *MR = LV.getAsRegion(); 119162767Ssilby if (MR && Mgr.getOwningEngine() && notifyChanges) 120162767Ssilby return Mgr.getOwningEngine()->processRegionChange(newState, MR); 121162767Ssilby 122162767Ssilby return newState; 123162767Ssilby} 124162767Ssilby 125162031SglebiusProgramStateRef ProgramState::bindDefault(SVal loc, SVal V) const { 126162031Sglebius ProgramStateManager &Mgr = getStateManager(); 127162031Sglebius const MemRegion *R = loc.castAs<loc::MemRegionVal>().getRegion(); 128157478Sglebius const StoreRef &newStore = Mgr.StoreMgr->BindDefault(getStore(), R, V); 129162031Sglebius ProgramStateRef new_state = makeWithStore(newStore); 130162767Ssilby return Mgr.getOwningEngine() ? 131162031Sglebius Mgr.getOwningEngine()->processRegionChange(new_state, R) : 132162031Sglebius new_state; 133170289Sdwmalone} 134162767Ssilby 135162767Ssilbytypedef ArrayRef<const MemRegion *> RegionList; 136162031Sglebiustypedef ArrayRef<SVal> ValueList; 137162035Sglebius 138162767SsilbyProgramStateRef 139162031SglebiusProgramState::invalidateRegions(RegionList Regions, 140162031Sglebius const Expr *E, unsigned Count, 141169541Sandre const LocationContext *LCtx, 142162031Sglebius bool CausedByPointerEscape, 143162031Sglebius InvalidatedSymbols *IS, 144162031Sglebius const CallEvent *Call, 145162031Sglebius RegionAndSymbolInvalidationTraits *ITraits) const { 146162151Sglebius SmallVector<SVal, 8> Values; 147162151Sglebius for (RegionList::const_iterator I = Regions.begin(), 148167721Sandre End = Regions.end(); I != End; ++I) 149167721Sandre Values.push_back(loc::MemRegionVal(*I)); 150162151Sglebius 151169541Sandre return invalidateRegionsImpl(Values, E, Count, LCtx, CausedByPointerEscape, 152169541Sandre IS, ITraits, Call); 153157927Sps} 154157927Sps 155162031SglebiusProgramStateRef 156162767SsilbyProgramState::invalidateRegions(ValueList Values, 157157927Sps const Expr *E, unsigned Count, 158157927Sps const LocationContext *LCtx, 1591541Srgrimes bool CausedByPointerEscape, 160169541Sandre InvalidatedSymbols *IS, 1611541Srgrimes const CallEvent *Call, 162169454Srwatson RegionAndSymbolInvalidationTraits *ITraits) const { 163162031Sglebius 164162031Sglebius return invalidateRegionsImpl(Values, E, Count, LCtx, CausedByPointerEscape, 165157478Sglebius IS, ITraits, Call); 166157478Sglebius} 167162767Ssilby 168162031SglebiusProgramStateRef 169162031SglebiusProgramState::invalidateRegionsImpl(ValueList Values, 170169608Sandre const Expr *E, unsigned Count, 1711541Srgrimes const LocationContext *LCtx, 1721541Srgrimes bool CausedByPointerEscape, 1731541Srgrimes InvalidatedSymbols *IS, 174111145Sjlemon RegionAndSymbolInvalidationTraits *ITraits, 175138410Srwatson const CallEvent *Call) const { 176111145Sjlemon ProgramStateManager &Mgr = getStateManager(); 177111145Sjlemon SubEngine* Eng = Mgr.getOwningEngine(); 178111145Sjlemon 179157431Srwatson InvalidatedSymbols Invalidated; 180111145Sjlemon if (!IS) 181111145Sjlemon IS = &Invalidated; 182162151Sglebius 183162111Sru RegionAndSymbolInvalidationTraits ITraitsLocal; 184111145Sjlemon if (!ITraits) 185111145Sjlemon ITraits = &ITraitsLocal; 186169608Sandre 187162151Sglebius if (Eng) { 188138020Srwatson StoreManager::InvalidatedRegions TopLevelInvalidated; 189162151Sglebius StoreManager::InvalidatedRegions Invalidated; 190162151Sglebius const StoreRef &newStore 191162151Sglebius = Mgr.StoreMgr->invalidateRegions(getStore(), Values, E, Count, LCtx, Call, 192162151Sglebius *IS, *ITraits, &TopLevelInvalidated, 193162151Sglebius &Invalidated); 194162151Sglebius 195162151Sglebius ProgramStateRef newState = makeWithStore(newStore); 196112009Sjlemon 197112009Sjlemon if (CausedByPointerEscape) { 198169608Sandre newState = Eng->notifyCheckersOfPointerEscape(newState, IS, 199112009Sjlemon TopLevelInvalidated, 200157376Srwatson Invalidated, Call, 201157376Srwatson *ITraits); 202162151Sglebius } 203112009Sjlemon 204112009Sjlemon return Eng->processRegionChanges(newState, IS, TopLevelInvalidated, 205112009Sjlemon Invalidated, Call); 206111145Sjlemon } 207111145Sjlemon 208111145Sjlemon const StoreRef &newStore = 209111145Sjlemon Mgr.StoreMgr->invalidateRegions(getStore(), Values, E, Count, LCtx, Call, 210111145Sjlemon *IS, *ITraits, nullptr, nullptr); 211111145Sjlemon return makeWithStore(newStore); 212111145Sjlemon} 213111145Sjlemon 214111145SjlemonProgramStateRef ProgramState::killBinding(Loc LV) const { 215111145Sjlemon assert(!LV.getAs<loc::MemRegionVal>() && "Use invalidateRegion instead."); 216133874Srwatson 217169477Sandre Store OldStore = getStore(); 218111145Sjlemon const StoreRef &newStore = 219169477Sandre getStateManager().StoreMgr->killBinding(OldStore, LV); 220169477Sandre 221111145Sjlemon if (newStore.getStore() == OldStore) 222169477Sandre return this; 223169477Sandre 224111145Sjlemon return makeWithStore(newStore); 225111145Sjlemon} 226111145Sjlemon 227121850SsilbyProgramStateRef 228121884SsilbyProgramState::enterStackFrame(const CallEvent &Call, 229111145Sjlemon const StackFrameContext *CalleeCtx) const { 230112009Sjlemon const StoreRef &NewStore = 231111145Sjlemon getStateManager().StoreMgr->enterStackFrame(getStore(), Call, CalleeCtx); 232111145Sjlemon return makeWithStore(NewStore); 233111145Sjlemon} 234111145Sjlemon 235111145SjlemonSVal ProgramState::getSValAsScalarOrLoc(const MemRegion *R) const { 236111145Sjlemon // We only want to do fetches from regions that we can actually bind 237137139Sandre // values. For example, SymbolicRegions of type 'id<...>' cannot 238157376Srwatson // have direct bindings (but their can be bindings on their subregions). 239157376Srwatson if (!R->isBoundable()) 240157376Srwatson return UnknownVal(); 241157376Srwatson 242157376Srwatson if (const TypedValueRegion *TR = dyn_cast<TypedValueRegion>(R)) { 243160925Srwatson QualType T = TR->getValueType(); 244160925Srwatson if (Loc::isLocType(T) || T->isIntegralOrEnumerationType()) 245160925Srwatson return getSVal(R); 246157376Srwatson } 247111145Sjlemon 248111145Sjlemon return UnknownVal(); 249160925Srwatson} 250169347Srwatson 251130387SrwatsonSVal ProgramState::getSVal(Loc location, QualType T) const { 252111145Sjlemon SVal V = getRawSVal(cast<Loc>(location), T); 253157376Srwatson 254114794Srwatson // If 'V' is a symbolic value that is *perfectly* constrained to 255126351Srwatson // be a constant value, use that value instead to lessen the burden 256157432Srwatson // on later analysis stages (so we have less symbolic values to reason 257111145Sjlemon // about). 258169608Sandre if (!T.isNull()) { 259157376Srwatson if (SymbolRef sym = V.getAsSymbol()) { 260157376Srwatson if (const llvm::APSInt *Int = getStateManager() 261157376Srwatson .getConstraintManager() 262157376Srwatson .getSymVal(this, sym)) { 263157376Srwatson // FIXME: Because we don't correctly model (yet) sign-extension 264157376Srwatson // and truncation of symbolic values, we need to convert 265157376Srwatson // the integer value to the correct signedness and bitwidth. 266157376Srwatson // 267157376Srwatson // This shows up in the following: 268157376Srwatson // 269157376Srwatson // char foo(); 270157376Srwatson // unsigned x = foo(); 271157376Srwatson // if (x == 54) 272157376Srwatson // ... 273157376Srwatson // 274157376Srwatson // The symbolic value stored to 'x' is actually the conjured 275111145Sjlemon // symbol for the call to foo(); the type of that symbol is 'char', 276111145Sjlemon // not unsigned. 277162064Sglebius const llvm::APSInt &NewV = getBasicVals().Convert(T, *Int); 278121850Ssilby 279121884Ssilby if (V.getAs<Loc>()) 280121884Ssilby return loc::ConcreteInt(NewV); 281121884Ssilby else 282121884Ssilby return nonloc::ConcreteInt(NewV); 283121884Ssilby } 284121884Ssilby } 285121884Ssilby } 286121884Ssilby 287121884Ssilby return V; 288121884Ssilby} 289121850Ssilby 290121850SsilbyProgramStateRef ProgramState::BindExpr(const Stmt *S, 291121850Ssilby const LocationContext *LCtx, 292121850Ssilby SVal V, bool Invalidate) const{ 293121850Ssilby Environment NewEnv = 294121850Ssilby getStateManager().EnvMgr.bindExpr(Env, EnvironmentEntry(S, LCtx), V, 295121850Ssilby Invalidate); 296121884Ssilby if (NewEnv == Env) 297121884Ssilby return this; 298121850Ssilby 299162064Sglebius ProgramState NewSt = *this; 300121884Ssilby NewSt.Env = NewEnv; 301121884Ssilby return getStateManager().getPersistentState(NewSt); 302133874Srwatson} 303121884Ssilby 304139222SrwatsonProgramStateRef ProgramState::assumeInBound(DefinedOrUnknownSVal Idx, 305121850Ssilby DefinedOrUnknownSVal UpperBound, 306139222Srwatson bool Assumption, 307121850Ssilby QualType indexTy) const { 308162064Sglebius if (Idx.isUnknown() || UpperBound.isUnknown()) 309121850Ssilby return this; 310169608Sandre 311169608Sandre // Build an expression for 0 <= Idx < UpperBound. 312169608Sandre // This is the same as Idx + MIN < UpperBound + MIN, if overflow is allowed. 313169608Sandre // FIXME: This should probably be part of SValBuilder. 314169608Sandre ProgramStateManager &SM = getStateManager(); 315169608Sandre SValBuilder &svalBuilder = SM.getSValBuilder(); 316169608Sandre ASTContext &Ctx = svalBuilder.getContext(); 317169608Sandre 318169608Sandre // Get the offset: the minimum value of the array index type. 319169608Sandre BasicValueFactory &BVF = svalBuilder.getBasicValueFactory(); 320169608Sandre // FIXME: This should be using ValueManager::ArrayindexTy...somehow. 321169608Sandre if (indexTy.isNull()) 322169608Sandre indexTy = Ctx.IntTy; 323169608Sandre nonloc::ConcreteInt Min(BVF.getMinValue(indexTy)); 324169608Sandre 325169608Sandre // Adjust the index. 326169608Sandre SVal newIdx = svalBuilder.evalBinOpNN(this, BO_Add, 327169608Sandre Idx.castAs<NonLoc>(), Min, indexTy); 328169608Sandre if (newIdx.isUnknownOrUndef()) 329169608Sandre return this; 330169608Sandre 331169608Sandre // Adjust the upper bound. 332169608Sandre SVal newBound = 333169608Sandre svalBuilder.evalBinOpNN(this, BO_Add, UpperBound.castAs<NonLoc>(), 334169608Sandre Min, indexTy); 335169608Sandre 336169608Sandre if (newBound.isUnknownOrUndef()) 337169608Sandre return this; 338169608Sandre 339169608Sandre // Build the actual comparison. 340169608Sandre SVal inBound = svalBuilder.evalBinOpNN(this, BO_LT, newIdx.castAs<NonLoc>(), 341169608Sandre newBound.castAs<NonLoc>(), Ctx.IntTy); 342169608Sandre if (inBound.isUnknownOrUndef()) 343169608Sandre return this; 344169608Sandre 345169608Sandre // Finally, let the constraint manager take care of it. 346169608Sandre ConstraintManager &CM = SM.getConstraintManager(); 347169608Sandre return CM.assume(this, inBound.castAs<DefinedSVal>(), Assumption); 348169608Sandre} 349169608Sandre 350169608SandreConditionTruthVal ProgramState::isNull(SVal V) const { 351169608Sandre if (V.isZeroConstant()) 352169608Sandre return true; 353169608Sandre 354169608Sandre if (V.isConstant()) 355169608Sandre return false; 356169608Sandre 357169608Sandre SymbolRef Sym = V.getAsSymbol(/* IncludeBaseRegion */ true); 358169608Sandre if (!Sym) 359169608Sandre return ConditionTruthVal(); 360169608Sandre 361169608Sandre return getStateManager().ConstraintMgr->isNull(this, Sym); 362169608Sandre} 363169608Sandre 364169608SandreProgramStateRef ProgramStateManager::getInitialState(const LocationContext *InitLoc) { 365169608Sandre ProgramState State(this, 366169608Sandre EnvMgr.getInitialEnvironment(), 367169608Sandre StoreMgr->getInitialStore(InitLoc), 368169608Sandre GDMFactory.getEmptyMap()); 369169608Sandre 370169608Sandre return getPersistentState(State); 371169608Sandre} 372169608Sandre 373169608SandreProgramStateRef ProgramStateManager::getPersistentStateWithGDM( 374169608Sandre ProgramStateRef FromState, 375169608Sandre ProgramStateRef GDMState) { 376169608Sandre ProgramState NewState(*FromState); 377169608Sandre NewState.GDM = GDMState->GDM; 378169608Sandre return getPersistentState(NewState); 379169608Sandre} 380169608Sandre 381169608SandreProgramStateRef ProgramStateManager::getPersistentState(ProgramState &State) { 382169608Sandre 383169608Sandre llvm::FoldingSetNodeID ID; 384169608Sandre State.Profile(ID); 385169608Sandre void *InsertPos; 386169608Sandre 387169608Sandre if (ProgramState *I = StateSet.FindNodeOrInsertPos(ID, InsertPos)) 388169608Sandre return I; 389169608Sandre 390169608Sandre ProgramState *newState = nullptr; 391169608Sandre if (!freeStates.empty()) { 392169608Sandre newState = freeStates.back(); 393169608Sandre freeStates.pop_back(); 394169608Sandre } 395169608Sandre else { 396169608Sandre newState = (ProgramState*) Alloc.Allocate<ProgramState>(); 397169608Sandre } 398169608Sandre new (newState) ProgramState(State); 399169608Sandre StateSet.InsertNode(newState, InsertPos); 400169608Sandre return newState; 401169608Sandre} 402169608Sandre 403169608SandreProgramStateRef ProgramState::makeWithStore(const StoreRef &store) const { 404169608Sandre ProgramState NewSt(*this); 405169608Sandre NewSt.setStore(store); 406169608Sandre return getStateManager().getPersistentState(NewSt); 407169608Sandre} 408169608Sandre 409169608Sandrevoid ProgramState::setStore(const StoreRef &newStore) { 410169608Sandre Store newStoreStore = newStore.getStore(); 411169608Sandre if (newStoreStore) 412169608Sandre stateMgr->getStoreManager().incrementReferenceCount(newStoreStore); 413169608Sandre if (store) 414169608Sandre stateMgr->getStoreManager().decrementReferenceCount(store); 415169635Soleg store = newStoreStore; 416169608Sandre} 417169608Sandre 418169608Sandre//===----------------------------------------------------------------------===// 419169608Sandre// State pretty-printing. 420169608Sandre//===----------------------------------------------------------------------===// 421169608Sandre 422169608Sandrevoid ProgramState::print(raw_ostream &Out, 423169635Soleg const char *NL, const char *Sep) const { 424169608Sandre // Print the store. 425169608Sandre ProgramStateManager &Mgr = getStateManager(); 426169608Sandre Mgr.getStoreManager().print(getStore(), Out, NL, Sep); 427169608Sandre 428169608Sandre // Print out the environment. 429169608Sandre Env.print(Out, NL, Sep); 430169608Sandre 431169608Sandre // Print out the constraints. 432169608Sandre Mgr.getConstraintManager().print(this, Out, NL, Sep); 433169608Sandre 434169608Sandre // Print checker-specific data. 435169608Sandre Mgr.getOwningEngine()->printState(Out, this, NL, Sep); 436169608Sandre} 437169608Sandre 438169608Sandrevoid ProgramState::printDOT(raw_ostream &Out) const { 439169608Sandre print(Out, "\\l", "\\|"); 440169608Sandre} 441169608Sandre 442169608SandreLLVM_DUMP_METHOD void ProgramState::dump() const { 443169608Sandre print(llvm::errs()); 444169608Sandre} 445169608Sandre 446169608Sandrevoid ProgramState::printTaint(raw_ostream &Out, 447169608Sandre const char *NL, const char *Sep) const { 448169608Sandre TaintMapImpl TM = get<TaintMap>(); 449169608Sandre 450169608Sandre if (!TM.isEmpty()) 451157376Srwatson Out <<"Tainted Symbols:" << NL; 452112009Sjlemon 453111145Sjlemon for (TaintMapImpl::iterator I = TM.begin(), E = TM.end(); I != E; ++I) { 454157376Srwatson Out << I->first << " : " << I->second << NL; 455111145Sjlemon } 456111145Sjlemon} 457157376Srwatson 458157386Srwatsonvoid ProgramState::dumpTaint() const { 459157376Srwatson printTaint(llvm::errs()); 460160549Srwatson} 461160549Srwatson 462157386Srwatson//===----------------------------------------------------------------------===// 463160549Srwatson// Generic Data Map. 464160549Srwatson//===----------------------------------------------------------------------===// 465157376Srwatson 466111145Sjlemonvoid *const* ProgramState::FindGDM(void *K) const { 467157376Srwatson return GDM.lookup(K); 468157432Srwatson} 469169608Sandre 470138020Srwatsonvoid* 471138020SrwatsonProgramStateManager::FindGDMContext(void *K, 472111145Sjlemon void *(*CreateContext)(llvm::BumpPtrAllocator&), 473169608Sandre void (*DeleteContext)(void*)) { 474111145Sjlemon 475158009Srwatson std::pair<void*, void (*)(void*)>& p = GDMContexts[K]; 476157376Srwatson if (!p.first) { 477157376Srwatson p.first = CreateContext(Alloc); 478157386Srwatson p.second = DeleteContext; 479160549Srwatson } 480160549Srwatson 481160549Srwatson return p.first; 482160549Srwatson} 483160549Srwatson 484160549SrwatsonProgramStateRef ProgramStateManager::addGDM(ProgramStateRef St, void *Key, void *Data){ 485157386Srwatson ProgramState::GenericDataMap M1 = St->getGDM(); 486157386Srwatson ProgramState::GenericDataMap M2 = GDMFactory.add(M1, Key, Data); 487160549Srwatson 488157386Srwatson if (M1 == M2) 489157386Srwatson return St; 490157386Srwatson 491157386Srwatson ProgramState NewSt = *St; 492157386Srwatson NewSt.GDM = M2; 493157386Srwatson return getPersistentState(NewSt); 494157376Srwatson} 495157386Srwatson 496157386SrwatsonProgramStateRef ProgramStateManager::removeGDM(ProgramStateRef state, void *Key) { 497157386Srwatson ProgramState::GenericDataMap OldM = state->getGDM(); 498157386Srwatson ProgramState::GenericDataMap NewM = GDMFactory.remove(OldM, Key); 499157386Srwatson 500157386Srwatson if (NewM == OldM) 501157376Srwatson return state; 502157386Srwatson 503157376Srwatson ProgramState NewState = *state; 504157376Srwatson NewState.GDM = NewM; 505157376Srwatson return getPersistentState(NewState); 506157376Srwatson} 507157376Srwatson 508157376Srwatsonbool ScanReachableSymbols::scan(nonloc::LazyCompoundVal val) { 509157386Srwatson bool wasVisited = !visited.insert(val.getCVData()).second; 510111145Sjlemon if (wasVisited) 511126002Spjd return true; 512126002Spjd 513112009Sjlemon StoreManager &StoreMgr = state->getStateManager().getStoreManager(); 514157376Srwatson // FIXME: We don't really want to use getBaseRegion() here because pointer 515112009Sjlemon // arithmetic doesn't apply, but scanReachableSymbols only accepts base 516111145Sjlemon // regions right now. 517111145Sjlemon const MemRegion *R = val.getRegion()->getBaseRegion(); 518111145Sjlemon return StoreMgr.scanReachableSymbols(val.getStore(), R, *this); 519126351Srwatson} 520111145Sjlemon 521111145Sjlemonbool ScanReachableSymbols::scan(nonloc::CompoundVal val) { 522111145Sjlemon for (nonloc::CompoundVal::iterator I=val.begin(), E=val.end(); I!=E; ++I) 523111145Sjlemon if (!scan(*I)) 524111145Sjlemon return false; 525111145Sjlemon 526111145Sjlemon return true; 527168845Sandre} 528111145Sjlemon 529111145Sjlemonbool ScanReachableSymbols::scan(const SymExpr *sym) { 530111145Sjlemon for (SymExpr::symbol_iterator SI = sym->symbol_begin(), 531111145Sjlemon SE = sym->symbol_end(); 532111145Sjlemon SI != SE; ++SI) { 533138020Srwatson bool wasVisited = !visited.insert(*SI).second; 534138020Srwatson if (wasVisited) 535151967Sandre continue; 536111145Sjlemon 537111145Sjlemon if (!visitor.VisitSymbol(*SI)) 538111145Sjlemon return false; 539111145Sjlemon } 540114794Srwatson 541123607Srwatson return true; 542114794Srwatson} 543114794Srwatson 544111153Sjlemonbool ScanReachableSymbols::scan(SVal val) { 545111145Sjlemon if (Optional<loc::MemRegionVal> X = val.getAs<loc::MemRegionVal>()) 546111145Sjlemon return scan(X->getRegion()); 547111145Sjlemon 548111145Sjlemon if (Optional<nonloc::LazyCompoundVal> X = 549111145Sjlemon val.getAs<nonloc::LazyCompoundVal>()) 550111153Sjlemon return scan(*X); 551111153Sjlemon 552111153Sjlemon if (Optional<nonloc::LocAsInteger> X = val.getAs<nonloc::LocAsInteger>()) 553111145Sjlemon return scan(X->getLoc()); 554111145Sjlemon 555111145Sjlemon if (SymbolRef Sym = val.getAsSymbol()) 556111145Sjlemon return scan(Sym); 557111145Sjlemon 558168845Sandre if (const SymExpr *Sym = val.getAsSymbolicExpression()) 559133874Srwatson return scan(Sym); 560133874Srwatson 561111145Sjlemon if (Optional<nonloc::CompoundVal> X = val.getAs<nonloc::CompoundVal>()) 562111145Sjlemon return scan(*X); 563133874Srwatson 564111145Sjlemon return true; 565168845Sandre} 566169477Sandre 567168845Sandrebool ScanReachableSymbols::scan(const MemRegion *R) { 568133874Srwatson if (isa<MemSpaceRegion>(R)) 569168845Sandre return true; 570111145Sjlemon 571111145Sjlemon bool wasVisited = !visited.insert(R).second; 572111145Sjlemon if (wasVisited) 573111145Sjlemon return true; 574111145Sjlemon 575111145Sjlemon if (!visitor.VisitMemRegion(R)) 576111145Sjlemon return false; 577111145Sjlemon 578111145Sjlemon // If this is a symbolic region, visit the symbol for the region. 579111145Sjlemon if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) 580111145Sjlemon if (!visitor.VisitSymbol(SR->getSymbol())) 581111145Sjlemon return false; 582111153Sjlemon 583111145Sjlemon // If this is a subregion, also visit the parent regions. 584111145Sjlemon if (const SubRegion *SR = dyn_cast<SubRegion>(R)) { 585111145Sjlemon const MemRegion *Super = SR->getSuperRegion(); 586122922Sandre if (!scan(Super)) 587122922Sandre return false; 588111145Sjlemon 589111153Sjlemon // When we reach the topmost region, scan all symbols in it. 590111153Sjlemon if (isa<MemSpaceRegion>(Super)) { 591111153Sjlemon StoreManager &StoreMgr = state->getStateManager().getStoreManager(); 592111145Sjlemon if (!StoreMgr.scanReachableSymbols(state->getStore(), SR, *this)) 593133874Srwatson return false; 594111145Sjlemon } 595111145Sjlemon } 596111145Sjlemon 597124248Sandre // Regions captured by a block are also implicitly reachable. 598124248Sandre if (const BlockDataRegion *BDR = dyn_cast<BlockDataRegion>(R)) { 599122922Sandre BlockDataRegion::referenced_vars_iterator I = BDR->referenced_vars_begin(), 600134793Sjmg E = BDR->referenced_vars_end(); 601134793Sjmg for ( ; I != E; ++I) { 602111145Sjlemon if (!scan(I.getCapturedRegion())) 603111145Sjlemon return false; 604111145Sjlemon } 605111145Sjlemon } 606111145Sjlemon 607111145Sjlemon return true; 608111145Sjlemon} 609111145Sjlemon 610169608Sandrebool ProgramState::scanReachableSymbols(SVal val, SymbolVisitor& visitor) const { 611169608Sandre ScanReachableSymbols S(this, visitor); 612169608Sandre return S.scan(val); 613169608Sandre} 614169608Sandre 615169608Sandrebool ProgramState::scanReachableSymbols(const SVal *I, const SVal *E, 616169608Sandre SymbolVisitor &visitor) const { 617169608Sandre ScanReachableSymbols S(this, visitor); 618169608Sandre for ( ; I != E; ++I) { 619169608Sandre if (!S.scan(*I)) 620169608Sandre return false; 621169608Sandre } 622169608Sandre return true; 623169608Sandre} 624169608Sandre 625169608Sandrebool ProgramState::scanReachableSymbols(const MemRegion * const *I, 626169608Sandre const MemRegion * const *E, 627169608Sandre SymbolVisitor &visitor) const { 628169608Sandre ScanReachableSymbols S(this, visitor); 629169608Sandre for ( ; I != E; ++I) { 630169608Sandre if (!S.scan(*I)) 631169608Sandre return false; 632169608Sandre } 633169608Sandre return true; 634169608Sandre} 635169608Sandre 636169608SandreProgramStateRef ProgramState::addTaint(const Stmt *S, 637169608Sandre const LocationContext *LCtx, 638169608Sandre TaintTagType Kind) const { 639169608Sandre if (const Expr *E = dyn_cast_or_null<Expr>(S)) 640169608Sandre S = E->IgnoreParens(); 641169608Sandre 642169608Sandre SymbolRef Sym = getSVal(S, LCtx).getAsSymbol(); 643169608Sandre if (Sym) 644169608Sandre return addTaint(Sym, Kind); 645169608Sandre 646169608Sandre const MemRegion *R = getSVal(S, LCtx).getAsRegion(); 647169608Sandre addTaint(R, Kind); 648 649 // Cannot add taint, so just return the state. 650 return this; 651} 652 653ProgramStateRef ProgramState::addTaint(const MemRegion *R, 654 TaintTagType Kind) const { 655 if (const SymbolicRegion *SR = dyn_cast_or_null<SymbolicRegion>(R)) 656 return addTaint(SR->getSymbol(), Kind); 657 return this; 658} 659 660ProgramStateRef ProgramState::addTaint(SymbolRef Sym, 661 TaintTagType Kind) const { 662 // If this is a symbol cast, remove the cast before adding the taint. Taint 663 // is cast agnostic. 664 while (const SymbolCast *SC = dyn_cast<SymbolCast>(Sym)) 665 Sym = SC->getOperand(); 666 667 ProgramStateRef NewState = set<TaintMap>(Sym, Kind); 668 assert(NewState); 669 return NewState; 670} 671 672bool ProgramState::isTainted(const Stmt *S, const LocationContext *LCtx, 673 TaintTagType Kind) const { 674 if (const Expr *E = dyn_cast_or_null<Expr>(S)) 675 S = E->IgnoreParens(); 676 677 SVal val = getSVal(S, LCtx); 678 return isTainted(val, Kind); 679} 680 681bool ProgramState::isTainted(SVal V, TaintTagType Kind) const { 682 if (const SymExpr *Sym = V.getAsSymExpr()) 683 return isTainted(Sym, Kind); 684 if (const MemRegion *Reg = V.getAsRegion()) 685 return isTainted(Reg, Kind); 686 return false; 687} 688 689bool ProgramState::isTainted(const MemRegion *Reg, TaintTagType K) const { 690 if (!Reg) 691 return false; 692 693 // Element region (array element) is tainted if either the base or the offset 694 // are tainted. 695 if (const ElementRegion *ER = dyn_cast<ElementRegion>(Reg)) 696 return isTainted(ER->getSuperRegion(), K) || isTainted(ER->getIndex(), K); 697 698 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(Reg)) 699 return isTainted(SR->getSymbol(), K); 700 701 if (const SubRegion *ER = dyn_cast<SubRegion>(Reg)) 702 return isTainted(ER->getSuperRegion(), K); 703 704 return false; 705} 706 707bool ProgramState::isTainted(SymbolRef Sym, TaintTagType Kind) const { 708 if (!Sym) 709 return false; 710 711 // Traverse all the symbols this symbol depends on to see if any are tainted. 712 bool Tainted = false; 713 for (SymExpr::symbol_iterator SI = Sym->symbol_begin(), SE =Sym->symbol_end(); 714 SI != SE; ++SI) { 715 if (!isa<SymbolData>(*SI)) 716 continue; 717 718 const TaintTagType *Tag = get<TaintMap>(*SI); 719 Tainted = (Tag && *Tag == Kind); 720 721 // If this is a SymbolDerived with a tainted parent, it's also tainted. 722 if (const SymbolDerived *SD = dyn_cast<SymbolDerived>(*SI)) 723 Tainted = Tainted || isTainted(SD->getParentSymbol(), Kind); 724 725 // If memory region is tainted, data is also tainted. 726 if (const SymbolRegionValue *SRV = dyn_cast<SymbolRegionValue>(*SI)) 727 Tainted = Tainted || isTainted(SRV->getRegion(), Kind); 728 729 // If If this is a SymbolCast from a tainted value, it's also tainted. 730 if (const SymbolCast *SC = dyn_cast<SymbolCast>(*SI)) 731 Tainted = Tainted || isTainted(SC->getOperand(), Kind); 732 733 if (Tainted) 734 return true; 735 } 736 737 return Tainted; 738} 739 740