1 //= ProgramState.cpp - Path-Sensitive "State" for tracking values --*- C++ -*--=
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements ProgramState and ProgramStateManager.
12 //===----------------------------------------------------------------------===//
14 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
15 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
16 #include "clang/Analysis/CFG.h"
17 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
18 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
19 #include "clang/StaticAnalyzer/Core/PathSensitive/SubEngine.h"
20 #include "clang/StaticAnalyzer/Core/PathSensitive/TaintManager.h"
21 #include "clang/StaticAnalyzer/Core/PathSensitive/DynamicTypeMap.h"
22 #include "llvm/Support/raw_ostream.h"
24 using namespace clang;
27 namespace clang { namespace ento {
28 /// Increments the number of times this state is referenced.
30 void ProgramStateRetain(const ProgramState *state) {
31 ++const_cast<ProgramState*>(state)->refCount;
34 /// Decrement the number of times this state is referenced.
35 void ProgramStateRelease(const ProgramState *state) {
36 assert(state->refCount > 0);
37 ProgramState *s = const_cast<ProgramState*>(state);
38 if (--s->refCount == 0) {
39 ProgramStateManager &Mgr = s->getStateManager();
40 Mgr.StateSet.RemoveNode(s);
42 Mgr.freeStates.push_back(s);
47 ProgramState::ProgramState(ProgramStateManager *mgr, const Environment& env,
48 StoreRef st, GenericDataMap gdm)
54 stateMgr->getStoreManager().incrementReferenceCount(store);
57 ProgramState::ProgramState(const ProgramState &RHS)
58 : llvm::FoldingSetNode(),
59 stateMgr(RHS.stateMgr),
64 stateMgr->getStoreManager().incrementReferenceCount(store);
67 ProgramState::~ProgramState() {
69 stateMgr->getStoreManager().decrementReferenceCount(store);
72 int64_t ProgramState::getID() const {
73 return getStateManager().Alloc.identifyKnownAlignedObject<ProgramState>(this);
76 ProgramStateManager::ProgramStateManager(ASTContext &Ctx,
77 StoreManagerCreator CreateSMgr,
78 ConstraintManagerCreator CreateCMgr,
79 llvm::BumpPtrAllocator &alloc,
81 : Eng(SubEng), EnvMgr(alloc), GDMFactory(alloc),
82 svalBuilder(createSimpleSValBuilder(alloc, Ctx, *this)),
83 CallEventMgr(new CallEventManager(alloc)), Alloc(alloc) {
84 StoreMgr = (*CreateSMgr)(*this);
85 ConstraintMgr = (*CreateCMgr)(*this, SubEng);
89 ProgramStateManager::~ProgramStateManager() {
90 for (GDMContextsTy::iterator I=GDMContexts.begin(), E=GDMContexts.end();
92 I->second.second(I->second.first);
96 ProgramStateManager::removeDeadBindings(ProgramStateRef state,
97 const StackFrameContext *LCtx,
98 SymbolReaper& SymReaper) {
100 // This code essentially performs a "mark-and-sweep" of the VariableBindings.
101 // The roots are any Block-level exprs and Decls that our liveness algorithm
102 // tells us are live. We then see what Decls they may reference, and keep
103 // those around. This code more than likely can be made faster, and the
104 // frequency of which this method is called should be experimented with
105 // for optimum performance.
106 ProgramState NewState = *state;
108 NewState.Env = EnvMgr.removeDeadBindings(NewState.Env, SymReaper, state);
110 // Clean up the store.
111 StoreRef newStore = StoreMgr->removeDeadBindings(NewState.getStore(), LCtx,
113 NewState.setStore(newStore);
114 SymReaper.setReapedStore(newStore);
116 ProgramStateRef Result = getPersistentState(NewState);
117 return ConstraintMgr->removeDeadBindings(Result, SymReaper);
120 ProgramStateRef ProgramState::bindLoc(Loc LV,
122 const LocationContext *LCtx,
123 bool notifyChanges) const {
124 ProgramStateManager &Mgr = getStateManager();
125 ProgramStateRef newState = makeWithStore(Mgr.StoreMgr->Bind(getStore(),
127 const MemRegion *MR = LV.getAsRegion();
128 if (MR && notifyChanges)
129 return Mgr.getOwningEngine().processRegionChange(newState, MR, LCtx);
135 ProgramState::bindDefaultInitial(SVal loc, SVal V,
136 const LocationContext *LCtx) const {
137 ProgramStateManager &Mgr = getStateManager();
138 const MemRegion *R = loc.castAs<loc::MemRegionVal>().getRegion();
139 const StoreRef &newStore = Mgr.StoreMgr->BindDefaultInitial(getStore(), R, V);
140 ProgramStateRef new_state = makeWithStore(newStore);
141 return Mgr.getOwningEngine().processRegionChange(new_state, R, LCtx);
145 ProgramState::bindDefaultZero(SVal loc, const LocationContext *LCtx) const {
146 ProgramStateManager &Mgr = getStateManager();
147 const MemRegion *R = loc.castAs<loc::MemRegionVal>().getRegion();
148 const StoreRef &newStore = Mgr.StoreMgr->BindDefaultZero(getStore(), R);
149 ProgramStateRef new_state = makeWithStore(newStore);
150 return Mgr.getOwningEngine().processRegionChange(new_state, R, LCtx);
153 typedef ArrayRef<const MemRegion *> RegionList;
154 typedef ArrayRef<SVal> ValueList;
157 ProgramState::invalidateRegions(RegionList Regions,
158 const Expr *E, unsigned Count,
159 const LocationContext *LCtx,
160 bool CausedByPointerEscape,
161 InvalidatedSymbols *IS,
162 const CallEvent *Call,
163 RegionAndSymbolInvalidationTraits *ITraits) const {
164 SmallVector<SVal, 8> Values;
165 for (RegionList::const_iterator I = Regions.begin(),
166 End = Regions.end(); I != End; ++I)
167 Values.push_back(loc::MemRegionVal(*I));
169 return invalidateRegionsImpl(Values, E, Count, LCtx, CausedByPointerEscape,
174 ProgramState::invalidateRegions(ValueList Values,
175 const Expr *E, unsigned Count,
176 const LocationContext *LCtx,
177 bool CausedByPointerEscape,
178 InvalidatedSymbols *IS,
179 const CallEvent *Call,
180 RegionAndSymbolInvalidationTraits *ITraits) const {
182 return invalidateRegionsImpl(Values, E, Count, LCtx, CausedByPointerEscape,
187 ProgramState::invalidateRegionsImpl(ValueList Values,
188 const Expr *E, unsigned Count,
189 const LocationContext *LCtx,
190 bool CausedByPointerEscape,
191 InvalidatedSymbols *IS,
192 RegionAndSymbolInvalidationTraits *ITraits,
193 const CallEvent *Call) const {
194 ProgramStateManager &Mgr = getStateManager();
195 SubEngine &Eng = Mgr.getOwningEngine();
197 InvalidatedSymbols InvalidatedSyms;
199 IS = &InvalidatedSyms;
201 RegionAndSymbolInvalidationTraits ITraitsLocal;
203 ITraits = &ITraitsLocal;
205 StoreManager::InvalidatedRegions TopLevelInvalidated;
206 StoreManager::InvalidatedRegions Invalidated;
207 const StoreRef &newStore
208 = Mgr.StoreMgr->invalidateRegions(getStore(), Values, E, Count, LCtx, Call,
209 *IS, *ITraits, &TopLevelInvalidated,
212 ProgramStateRef newState = makeWithStore(newStore);
214 if (CausedByPointerEscape) {
215 newState = Eng.notifyCheckersOfPointerEscape(newState, IS,
221 return Eng.processRegionChanges(newState, IS, TopLevelInvalidated,
222 Invalidated, LCtx, Call);
225 ProgramStateRef ProgramState::killBinding(Loc LV) const {
226 assert(!LV.getAs<loc::MemRegionVal>() && "Use invalidateRegion instead.");
228 Store OldStore = getStore();
229 const StoreRef &newStore =
230 getStateManager().StoreMgr->killBinding(OldStore, LV);
232 if (newStore.getStore() == OldStore)
235 return makeWithStore(newStore);
239 ProgramState::enterStackFrame(const CallEvent &Call,
240 const StackFrameContext *CalleeCtx) const {
241 const StoreRef &NewStore =
242 getStateManager().StoreMgr->enterStackFrame(getStore(), Call, CalleeCtx);
243 return makeWithStore(NewStore);
246 SVal ProgramState::getSValAsScalarOrLoc(const MemRegion *R) const {
247 // We only want to do fetches from regions that we can actually bind
248 // values. For example, SymbolicRegions of type 'id<...>' cannot
249 // have direct bindings (but their can be bindings on their subregions).
250 if (!R->isBoundable())
253 if (const TypedValueRegion *TR = dyn_cast<TypedValueRegion>(R)) {
254 QualType T = TR->getValueType();
255 if (Loc::isLocType(T) || T->isIntegralOrEnumerationType())
262 SVal ProgramState::getSVal(Loc location, QualType T) const {
263 SVal V = getRawSVal(location, T);
265 // If 'V' is a symbolic value that is *perfectly* constrained to
266 // be a constant value, use that value instead to lessen the burden
267 // on later analysis stages (so we have less symbolic values to reason
269 // We only go into this branch if we can convert the APSInt value we have
270 // to the type of T, which is not always the case (e.g. for void).
271 if (!T.isNull() && (T->isIntegralOrEnumerationType() || Loc::isLocType(T))) {
272 if (SymbolRef sym = V.getAsSymbol()) {
273 if (const llvm::APSInt *Int = getStateManager()
274 .getConstraintManager()
275 .getSymVal(this, sym)) {
276 // FIXME: Because we don't correctly model (yet) sign-extension
277 // and truncation of symbolic values, we need to convert
278 // the integer value to the correct signedness and bitwidth.
280 // This shows up in the following:
283 // unsigned x = foo();
287 // The symbolic value stored to 'x' is actually the conjured
288 // symbol for the call to foo(); the type of that symbol is 'char',
290 const llvm::APSInt &NewV = getBasicVals().Convert(T, *Int);
293 return loc::ConcreteInt(NewV);
295 return nonloc::ConcreteInt(NewV);
303 ProgramStateRef ProgramState::BindExpr(const Stmt *S,
304 const LocationContext *LCtx,
305 SVal V, bool Invalidate) const{
307 getStateManager().EnvMgr.bindExpr(Env, EnvironmentEntry(S, LCtx), V,
312 ProgramState NewSt = *this;
314 return getStateManager().getPersistentState(NewSt);
317 ProgramStateRef ProgramState::assumeInBound(DefinedOrUnknownSVal Idx,
318 DefinedOrUnknownSVal UpperBound,
320 QualType indexTy) const {
321 if (Idx.isUnknown() || UpperBound.isUnknown())
324 // Build an expression for 0 <= Idx < UpperBound.
325 // This is the same as Idx + MIN < UpperBound + MIN, if overflow is allowed.
326 // FIXME: This should probably be part of SValBuilder.
327 ProgramStateManager &SM = getStateManager();
328 SValBuilder &svalBuilder = SM.getSValBuilder();
329 ASTContext &Ctx = svalBuilder.getContext();
331 // Get the offset: the minimum value of the array index type.
332 BasicValueFactory &BVF = svalBuilder.getBasicValueFactory();
333 if (indexTy.isNull())
334 indexTy = svalBuilder.getArrayIndexType();
335 nonloc::ConcreteInt Min(BVF.getMinValue(indexTy));
338 SVal newIdx = svalBuilder.evalBinOpNN(this, BO_Add,
339 Idx.castAs<NonLoc>(), Min, indexTy);
340 if (newIdx.isUnknownOrUndef())
343 // Adjust the upper bound.
345 svalBuilder.evalBinOpNN(this, BO_Add, UpperBound.castAs<NonLoc>(),
348 if (newBound.isUnknownOrUndef())
351 // Build the actual comparison.
352 SVal inBound = svalBuilder.evalBinOpNN(this, BO_LT, newIdx.castAs<NonLoc>(),
353 newBound.castAs<NonLoc>(), Ctx.IntTy);
354 if (inBound.isUnknownOrUndef())
357 // Finally, let the constraint manager take care of it.
358 ConstraintManager &CM = SM.getConstraintManager();
359 return CM.assume(this, inBound.castAs<DefinedSVal>(), Assumption);
362 ConditionTruthVal ProgramState::isNonNull(SVal V) const {
363 ConditionTruthVal IsNull = isNull(V);
364 if (IsNull.isUnderconstrained())
366 return ConditionTruthVal(!IsNull.getValue());
369 ConditionTruthVal ProgramState::areEqual(SVal Lhs, SVal Rhs) const {
370 return stateMgr->getSValBuilder().areEqual(this, Lhs, Rhs);
373 ConditionTruthVal ProgramState::isNull(SVal V) const {
374 if (V.isZeroConstant())
380 SymbolRef Sym = V.getAsSymbol(/* IncludeBaseRegion */ true);
382 return ConditionTruthVal();
384 return getStateManager().ConstraintMgr->isNull(this, Sym);
387 ProgramStateRef ProgramStateManager::getInitialState(const LocationContext *InitLoc) {
388 ProgramState State(this,
389 EnvMgr.getInitialEnvironment(),
390 StoreMgr->getInitialStore(InitLoc),
391 GDMFactory.getEmptyMap());
393 return getPersistentState(State);
396 ProgramStateRef ProgramStateManager::getPersistentStateWithGDM(
397 ProgramStateRef FromState,
398 ProgramStateRef GDMState) {
399 ProgramState NewState(*FromState);
400 NewState.GDM = GDMState->GDM;
401 return getPersistentState(NewState);
404 ProgramStateRef ProgramStateManager::getPersistentState(ProgramState &State) {
406 llvm::FoldingSetNodeID ID;
410 if (ProgramState *I = StateSet.FindNodeOrInsertPos(ID, InsertPos))
413 ProgramState *newState = nullptr;
414 if (!freeStates.empty()) {
415 newState = freeStates.back();
416 freeStates.pop_back();
419 newState = (ProgramState*) Alloc.Allocate<ProgramState>();
421 new (newState) ProgramState(State);
422 StateSet.InsertNode(newState, InsertPos);
426 ProgramStateRef ProgramState::makeWithStore(const StoreRef &store) const {
427 ProgramState NewSt(*this);
428 NewSt.setStore(store);
429 return getStateManager().getPersistentState(NewSt);
432 void ProgramState::setStore(const StoreRef &newStore) {
433 Store newStoreStore = newStore.getStore();
435 stateMgr->getStoreManager().incrementReferenceCount(newStoreStore);
437 stateMgr->getStoreManager().decrementReferenceCount(store);
438 store = newStoreStore;
441 //===----------------------------------------------------------------------===//
442 // State pretty-printing.
443 //===----------------------------------------------------------------------===//
445 void ProgramState::print(raw_ostream &Out,
446 const char *NL, const char *Sep,
447 const LocationContext *LC) const {
449 ProgramStateManager &Mgr = getStateManager();
450 const ASTContext &Context = getStateManager().getContext();
451 Mgr.getStoreManager().print(getStore(), Out, NL);
453 // Print out the environment.
454 Env.print(Out, NL, Sep, Context, LC);
456 // Print out the constraints.
457 Mgr.getConstraintManager().print(this, Out, NL, Sep);
459 // Print out the tracked dynamic types.
460 printDynamicTypeInfo(this, Out, NL, Sep);
462 // Print out tainted symbols.
465 // Print checker-specific data.
466 Mgr.getOwningEngine().printState(Out, this, NL, Sep, LC);
469 void ProgramState::printDOT(raw_ostream &Out,
470 const LocationContext *LC) const {
471 print(Out, "\\l", "\\|", LC);
474 LLVM_DUMP_METHOD void ProgramState::dump() const {
478 void ProgramState::printTaint(raw_ostream &Out,
479 const char *NL) const {
480 TaintMapImpl TM = get<TaintMap>();
483 Out <<"Tainted symbols:" << NL;
485 for (TaintMapImpl::iterator I = TM.begin(), E = TM.end(); I != E; ++I) {
486 Out << I->first << " : " << I->second << NL;
490 void ProgramState::dumpTaint() const {
491 printTaint(llvm::errs());
494 AnalysisManager& ProgramState::getAnalysisManager() const {
495 return stateMgr->getOwningEngine().getAnalysisManager();
498 //===----------------------------------------------------------------------===//
500 //===----------------------------------------------------------------------===//
502 void *const* ProgramState::FindGDM(void *K) const {
503 return GDM.lookup(K);
507 ProgramStateManager::FindGDMContext(void *K,
508 void *(*CreateContext)(llvm::BumpPtrAllocator&),
509 void (*DeleteContext)(void*)) {
511 std::pair<void*, void (*)(void*)>& p = GDMContexts[K];
513 p.first = CreateContext(Alloc);
514 p.second = DeleteContext;
520 ProgramStateRef ProgramStateManager::addGDM(ProgramStateRef St, void *Key, void *Data){
521 ProgramState::GenericDataMap M1 = St->getGDM();
522 ProgramState::GenericDataMap M2 = GDMFactory.add(M1, Key, Data);
527 ProgramState NewSt = *St;
529 return getPersistentState(NewSt);
532 ProgramStateRef ProgramStateManager::removeGDM(ProgramStateRef state, void *Key) {
533 ProgramState::GenericDataMap OldM = state->getGDM();
534 ProgramState::GenericDataMap NewM = GDMFactory.remove(OldM, Key);
539 ProgramState NewState = *state;
541 return getPersistentState(NewState);
544 bool ScanReachableSymbols::scan(nonloc::LazyCompoundVal val) {
545 bool wasVisited = !visited.insert(val.getCVData()).second;
549 StoreManager &StoreMgr = state->getStateManager().getStoreManager();
550 // FIXME: We don't really want to use getBaseRegion() here because pointer
551 // arithmetic doesn't apply, but scanReachableSymbols only accepts base
552 // regions right now.
553 const MemRegion *R = val.getRegion()->getBaseRegion();
554 return StoreMgr.scanReachableSymbols(val.getStore(), R, *this);
557 bool ScanReachableSymbols::scan(nonloc::CompoundVal val) {
558 for (nonloc::CompoundVal::iterator I=val.begin(), E=val.end(); I!=E; ++I)
565 bool ScanReachableSymbols::scan(const SymExpr *sym) {
566 for (SymExpr::symbol_iterator SI = sym->symbol_begin(),
567 SE = sym->symbol_end();
569 bool wasVisited = !visited.insert(*SI).second;
573 if (!visitor.VisitSymbol(*SI))
580 bool ScanReachableSymbols::scan(SVal val) {
581 if (Optional<loc::MemRegionVal> X = val.getAs<loc::MemRegionVal>())
582 return scan(X->getRegion());
584 if (Optional<nonloc::LazyCompoundVal> X =
585 val.getAs<nonloc::LazyCompoundVal>())
588 if (Optional<nonloc::LocAsInteger> X = val.getAs<nonloc::LocAsInteger>())
589 return scan(X->getLoc());
591 if (SymbolRef Sym = val.getAsSymbol())
594 if (const SymExpr *Sym = val.getAsSymbolicExpression())
597 if (Optional<nonloc::CompoundVal> X = val.getAs<nonloc::CompoundVal>())
603 bool ScanReachableSymbols::scan(const MemRegion *R) {
604 if (isa<MemSpaceRegion>(R))
607 bool wasVisited = !visited.insert(R).second;
611 if (!visitor.VisitMemRegion(R))
614 // If this is a symbolic region, visit the symbol for the region.
615 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R))
616 if (!visitor.VisitSymbol(SR->getSymbol()))
619 // If this is a subregion, also visit the parent regions.
620 if (const SubRegion *SR = dyn_cast<SubRegion>(R)) {
621 const MemRegion *Super = SR->getSuperRegion();
625 // When we reach the topmost region, scan all symbols in it.
626 if (isa<MemSpaceRegion>(Super)) {
627 StoreManager &StoreMgr = state->getStateManager().getStoreManager();
628 if (!StoreMgr.scanReachableSymbols(state->getStore(), SR, *this))
633 // Regions captured by a block are also implicitly reachable.
634 if (const BlockDataRegion *BDR = dyn_cast<BlockDataRegion>(R)) {
635 BlockDataRegion::referenced_vars_iterator I = BDR->referenced_vars_begin(),
636 E = BDR->referenced_vars_end();
637 for ( ; I != E; ++I) {
638 if (!scan(I.getCapturedRegion()))
646 bool ProgramState::scanReachableSymbols(SVal val, SymbolVisitor& visitor) const {
647 ScanReachableSymbols S(this, visitor);
651 bool ProgramState::scanReachableSymbols(
652 llvm::iterator_range<region_iterator> Reachable,
653 SymbolVisitor &visitor) const {
654 ScanReachableSymbols S(this, visitor);
655 for (const MemRegion *R : Reachable) {
662 ProgramStateRef ProgramState::addTaint(const Stmt *S,
663 const LocationContext *LCtx,
664 TaintTagType Kind) const {
665 if (const Expr *E = dyn_cast_or_null<Expr>(S))
666 S = E->IgnoreParens();
668 return addTaint(getSVal(S, LCtx), Kind);
671 ProgramStateRef ProgramState::addTaint(SVal V,
672 TaintTagType Kind) const {
673 SymbolRef Sym = V.getAsSymbol();
675 return addTaint(Sym, Kind);
677 // If the SVal represents a structure, try to mass-taint all values within the
678 // structure. For now it only works efficiently on lazy compound values that
679 // were conjured during a conservative evaluation of a function - either as
680 // return values of functions that return structures or arrays by value, or as
681 // values of structures or arrays passed into the function by reference,
682 // directly or through pointer aliasing. Such lazy compound values are
683 // characterized by having exactly one binding in their captured store within
684 // their parent region, which is a conjured symbol default-bound to the base
685 // region of the parent region.
686 if (auto LCV = V.getAs<nonloc::LazyCompoundVal>()) {
687 if (Optional<SVal> binding = getStateManager().StoreMgr->getDefaultBinding(*LCV)) {
688 if (SymbolRef Sym = binding->getAsSymbol())
689 return addPartialTaint(Sym, LCV->getRegion(), Kind);
693 const MemRegion *R = V.getAsRegion();
694 return addTaint(R, Kind);
697 ProgramStateRef ProgramState::addTaint(const MemRegion *R,
698 TaintTagType Kind) const {
699 if (const SymbolicRegion *SR = dyn_cast_or_null<SymbolicRegion>(R))
700 return addTaint(SR->getSymbol(), Kind);
704 ProgramStateRef ProgramState::addTaint(SymbolRef Sym,
705 TaintTagType Kind) const {
706 // If this is a symbol cast, remove the cast before adding the taint. Taint
708 while (const SymbolCast *SC = dyn_cast<SymbolCast>(Sym))
709 Sym = SC->getOperand();
711 ProgramStateRef NewState = set<TaintMap>(Sym, Kind);
716 ProgramStateRef ProgramState::addPartialTaint(SymbolRef ParentSym,
717 const SubRegion *SubRegion,
718 TaintTagType Kind) const {
719 // Ignore partial taint if the entire parent symbol is already tainted.
720 if (contains<TaintMap>(ParentSym) && *get<TaintMap>(ParentSym) == Kind)
723 // Partial taint applies if only a portion of the symbol is tainted.
724 if (SubRegion == SubRegion->getBaseRegion())
725 return addTaint(ParentSym, Kind);
727 const TaintedSubRegions *SavedRegs = get<DerivedSymTaint>(ParentSym);
728 TaintedSubRegions Regs =
729 SavedRegs ? *SavedRegs : stateMgr->TSRFactory.getEmptyMap();
731 Regs = stateMgr->TSRFactory.add(Regs, SubRegion, Kind);
732 ProgramStateRef NewState = set<DerivedSymTaint>(ParentSym, Regs);
737 bool ProgramState::isTainted(const Stmt *S, const LocationContext *LCtx,
738 TaintTagType Kind) const {
739 if (const Expr *E = dyn_cast_or_null<Expr>(S))
740 S = E->IgnoreParens();
742 SVal val = getSVal(S, LCtx);
743 return isTainted(val, Kind);
746 bool ProgramState::isTainted(SVal V, TaintTagType Kind) const {
747 if (const SymExpr *Sym = V.getAsSymExpr())
748 return isTainted(Sym, Kind);
749 if (const MemRegion *Reg = V.getAsRegion())
750 return isTainted(Reg, Kind);
754 bool ProgramState::isTainted(const MemRegion *Reg, TaintTagType K) const {
758 // Element region (array element) is tainted if either the base or the offset
760 if (const ElementRegion *ER = dyn_cast<ElementRegion>(Reg))
761 return isTainted(ER->getSuperRegion(), K) || isTainted(ER->getIndex(), K);
763 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(Reg))
764 return isTainted(SR->getSymbol(), K);
766 if (const SubRegion *ER = dyn_cast<SubRegion>(Reg))
767 return isTainted(ER->getSuperRegion(), K);
772 bool ProgramState::isTainted(SymbolRef Sym, TaintTagType Kind) const {
776 // Traverse all the symbols this symbol depends on to see if any are tainted.
777 for (SymExpr::symbol_iterator SI = Sym->symbol_begin(), SE =Sym->symbol_end();
779 if (!isa<SymbolData>(*SI))
782 if (const TaintTagType *Tag = get<TaintMap>(*SI)) {
787 if (const SymbolDerived *SD = dyn_cast<SymbolDerived>(*SI)) {
788 // If this is a SymbolDerived with a tainted parent, it's also tainted.
789 if (isTainted(SD->getParentSymbol(), Kind))
792 // If this is a SymbolDerived with the same parent symbol as another
793 // tainted SymbolDerived and a region that's a sub-region of that tainted
794 // symbol, it's also tainted.
795 if (const TaintedSubRegions *Regs =
796 get<DerivedSymTaint>(SD->getParentSymbol())) {
797 const TypedValueRegion *R = SD->getRegion();
798 for (auto I : *Regs) {
799 // FIXME: The logic to identify tainted regions could be more
800 // complete. For example, this would not currently identify
801 // overlapping fields in a union as tainted. To identify this we can
802 // check for overlapping/nested byte offsets.
803 if (Kind == I.second && R->isSubRegionOf(I.first))
809 // If memory region is tainted, data is also tainted.
810 if (const SymbolRegionValue *SRV = dyn_cast<SymbolRegionValue>(*SI)) {
811 if (isTainted(SRV->getRegion(), Kind))
815 // If this is a SymbolCast from a tainted value, it's also tainted.
816 if (const SymbolCast *SC = dyn_cast<SymbolCast>(*SI)) {
817 if (isTainted(SC->getOperand(), Kind))