755 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			755 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			C++
		
	
	
	
| //= ProgramState.cpp - Path-Sensitive "State" for tracking values --*- C++ -*--=
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is distributed under the University of Illinois Open Source
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| // License. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| //  This file implements ProgramState and ProgramStateManager.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
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| #include "clang/Analysis/CFG.h"
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| #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
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| #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
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| #include "clang/StaticAnalyzer/Core/PathSensitive/SubEngine.h"
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| #include "clang/StaticAnalyzer/Core/PathSensitive/TaintManager.h"
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| #include "llvm/Support/raw_ostream.h"
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| 
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| using namespace clang;
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| using namespace ento;
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| 
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| namespace clang { namespace  ento {
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| /// Increments the number of times this state is referenced.
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| 
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| void ProgramStateRetain(const ProgramState *state) {
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|   ++const_cast<ProgramState*>(state)->refCount;
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| }
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| 
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| /// Decrement the number of times this state is referenced.
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| void ProgramStateRelease(const ProgramState *state) {
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|   assert(state->refCount > 0);
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|   ProgramState *s = const_cast<ProgramState*>(state);
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|   if (--s->refCount == 0) {
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|     ProgramStateManager &Mgr = s->getStateManager();
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|     Mgr.StateSet.RemoveNode(s);
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|     s->~ProgramState();
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|     Mgr.freeStates.push_back(s);
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|   }
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| }
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| }}
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| 
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| ProgramState::ProgramState(ProgramStateManager *mgr, const Environment& env,
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|                  StoreRef st, GenericDataMap gdm)
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|   : stateMgr(mgr),
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|     Env(env),
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|     store(st.getStore()),
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|     GDM(gdm),
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|     refCount(0) {
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|   stateMgr->getStoreManager().incrementReferenceCount(store);
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| }
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| 
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| ProgramState::ProgramState(const ProgramState &RHS)
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|     : llvm::FoldingSetNode(),
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|       stateMgr(RHS.stateMgr),
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|       Env(RHS.Env),
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|       store(RHS.store),
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|       GDM(RHS.GDM),
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|       refCount(0) {
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|   stateMgr->getStoreManager().incrementReferenceCount(store);
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| }
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| 
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| ProgramState::~ProgramState() {
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|   if (store)
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|     stateMgr->getStoreManager().decrementReferenceCount(store);
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| }
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| 
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| ProgramStateManager::ProgramStateManager(ASTContext &Ctx,
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|                                          StoreManagerCreator CreateSMgr,
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|                                          ConstraintManagerCreator CreateCMgr,
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|                                          llvm::BumpPtrAllocator &alloc,
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|                                          SubEngine *SubEng)
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|   : Eng(SubEng), EnvMgr(alloc), GDMFactory(alloc),
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|     svalBuilder(createSimpleSValBuilder(alloc, Ctx, *this)),
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|     CallEventMgr(new CallEventManager(alloc)), Alloc(alloc) {
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|   StoreMgr = (*CreateSMgr)(*this);
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|   ConstraintMgr = (*CreateCMgr)(*this, SubEng);
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| }
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| 
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| 
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| ProgramStateManager::~ProgramStateManager() {
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|   for (GDMContextsTy::iterator I=GDMContexts.begin(), E=GDMContexts.end();
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|        I!=E; ++I)
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|     I->second.second(I->second.first);
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| }
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| 
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| ProgramStateRef
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| ProgramStateManager::removeDeadBindings(ProgramStateRef state,
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|                                    const StackFrameContext *LCtx,
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|                                    SymbolReaper& SymReaper) {
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| 
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|   // This code essentially performs a "mark-and-sweep" of the VariableBindings.
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|   // The roots are any Block-level exprs and Decls that our liveness algorithm
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|   // tells us are live.  We then see what Decls they may reference, and keep
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|   // those around.  This code more than likely can be made faster, and the
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|   // frequency of which this method is called should be experimented with
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|   // for optimum performance.
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|   ProgramState NewState = *state;
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| 
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|   NewState.Env = EnvMgr.removeDeadBindings(NewState.Env, SymReaper, state);
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| 
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|   // Clean up the store.
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|   StoreRef newStore = StoreMgr->removeDeadBindings(NewState.getStore(), LCtx,
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|                                                    SymReaper);
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|   NewState.setStore(newStore);
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|   SymReaper.setReapedStore(newStore);
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| 
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|   ProgramStateRef Result = getPersistentState(NewState);
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|   return ConstraintMgr->removeDeadBindings(Result, SymReaper);
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| }
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| 
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| ProgramStateRef ProgramState::bindLoc(Loc LV, SVal V, bool notifyChanges) const {
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|   ProgramStateManager &Mgr = getStateManager();
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|   ProgramStateRef newState = makeWithStore(Mgr.StoreMgr->Bind(getStore(),
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|                                                              LV, V));
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|   const MemRegion *MR = LV.getAsRegion();
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|   if (MR && Mgr.getOwningEngine() && notifyChanges)
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|     return Mgr.getOwningEngine()->processRegionChange(newState, MR);
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| 
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|   return newState;
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| }
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| 
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| ProgramStateRef ProgramState::bindDefault(SVal loc, SVal V) const {
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|   ProgramStateManager &Mgr = getStateManager();
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|   const MemRegion *R = loc.castAs<loc::MemRegionVal>().getRegion();
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|   const StoreRef &newStore = Mgr.StoreMgr->BindDefault(getStore(), R, V);
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|   ProgramStateRef new_state = makeWithStore(newStore);
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|   return Mgr.getOwningEngine() ?
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|            Mgr.getOwningEngine()->processRegionChange(new_state, R) :
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|            new_state;
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| }
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| 
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| typedef ArrayRef<const MemRegion *> RegionList;
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| typedef ArrayRef<SVal> ValueList;
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| 
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| ProgramStateRef
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| ProgramState::invalidateRegions(RegionList Regions,
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|                              const Expr *E, unsigned Count,
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|                              const LocationContext *LCtx,
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|                              bool CausedByPointerEscape,
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|                              InvalidatedSymbols *IS,
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|                              const CallEvent *Call,
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|                              RegionAndSymbolInvalidationTraits *ITraits) const {
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|   SmallVector<SVal, 8> Values;
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|   for (RegionList::const_iterator I = Regions.begin(),
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|                                   End = Regions.end(); I != End; ++I)
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|     Values.push_back(loc::MemRegionVal(*I));
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| 
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|   return invalidateRegionsImpl(Values, E, Count, LCtx, CausedByPointerEscape,
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|                                IS, ITraits, Call);
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| }
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| 
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| ProgramStateRef
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| ProgramState::invalidateRegions(ValueList Values,
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|                              const Expr *E, unsigned Count,
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|                              const LocationContext *LCtx,
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|                              bool CausedByPointerEscape,
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|                              InvalidatedSymbols *IS,
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|                              const CallEvent *Call,
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|                              RegionAndSymbolInvalidationTraits *ITraits) const {
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| 
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|   return invalidateRegionsImpl(Values, E, Count, LCtx, CausedByPointerEscape,
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|                                IS, ITraits, Call);
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| }
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| 
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| ProgramStateRef
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| ProgramState::invalidateRegionsImpl(ValueList Values,
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|                                     const Expr *E, unsigned Count,
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|                                     const LocationContext *LCtx,
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|                                     bool CausedByPointerEscape,
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|                                     InvalidatedSymbols *IS,
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|                                     RegionAndSymbolInvalidationTraits *ITraits,
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|                                     const CallEvent *Call) const {
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|   ProgramStateManager &Mgr = getStateManager();
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|   SubEngine* Eng = Mgr.getOwningEngine();
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| 
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|   InvalidatedSymbols Invalidated;
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|   if (!IS)
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|     IS = &Invalidated;
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| 
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|   RegionAndSymbolInvalidationTraits ITraitsLocal;
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|   if (!ITraits)
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|     ITraits = &ITraitsLocal;
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| 
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|   if (Eng) {
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|     StoreManager::InvalidatedRegions TopLevelInvalidated;
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|     StoreManager::InvalidatedRegions Invalidated;
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|     const StoreRef &newStore
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|     = Mgr.StoreMgr->invalidateRegions(getStore(), Values, E, Count, LCtx, Call,
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|                                       *IS, *ITraits, &TopLevelInvalidated,
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|                                       &Invalidated);
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| 
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|     ProgramStateRef newState = makeWithStore(newStore);
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| 
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|     if (CausedByPointerEscape) {
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|       newState = Eng->notifyCheckersOfPointerEscape(newState, IS,
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|                                                     TopLevelInvalidated,
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|                                                     Invalidated, Call,
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|                                                     *ITraits);
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|     }
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| 
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|     return Eng->processRegionChanges(newState, IS, TopLevelInvalidated,
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|                                      Invalidated, Call);
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|   }
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| 
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|   const StoreRef &newStore =
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|   Mgr.StoreMgr->invalidateRegions(getStore(), Values, E, Count, LCtx, Call,
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|                                   *IS, *ITraits, nullptr, nullptr);
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|   return makeWithStore(newStore);
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| }
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| 
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| ProgramStateRef ProgramState::killBinding(Loc LV) const {
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|   assert(!LV.getAs<loc::MemRegionVal>() && "Use invalidateRegion instead.");
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| 
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|   Store OldStore = getStore();
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|   const StoreRef &newStore =
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|     getStateManager().StoreMgr->killBinding(OldStore, LV);
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| 
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|   if (newStore.getStore() == OldStore)
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|     return this;
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| 
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|   return makeWithStore(newStore);
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| }
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| 
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| ProgramStateRef
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| ProgramState::enterStackFrame(const CallEvent &Call,
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|                               const StackFrameContext *CalleeCtx) const {
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|   const StoreRef &NewStore =
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|     getStateManager().StoreMgr->enterStackFrame(getStore(), Call, CalleeCtx);
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|   return makeWithStore(NewStore);
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| }
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| 
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| SVal ProgramState::getSValAsScalarOrLoc(const MemRegion *R) const {
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|   // We only want to do fetches from regions that we can actually bind
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|   // values.  For example, SymbolicRegions of type 'id<...>' cannot
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|   // have direct bindings (but their can be bindings on their subregions).
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|   if (!R->isBoundable())
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|     return UnknownVal();
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| 
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|   if (const TypedValueRegion *TR = dyn_cast<TypedValueRegion>(R)) {
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|     QualType T = TR->getValueType();
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|     if (Loc::isLocType(T) || T->isIntegralOrEnumerationType())
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|       return getSVal(R);
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|   }
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| 
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|   return UnknownVal();
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| }
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| 
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| SVal ProgramState::getSVal(Loc location, QualType T) const {
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|   SVal V = getRawSVal(cast<Loc>(location), T);
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| 
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|   // If 'V' is a symbolic value that is *perfectly* constrained to
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|   // be a constant value, use that value instead to lessen the burden
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|   // on later analysis stages (so we have less symbolic values to reason
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|   // about).
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|   if (!T.isNull()) {
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|     if (SymbolRef sym = V.getAsSymbol()) {
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|       if (const llvm::APSInt *Int = getStateManager()
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|                                     .getConstraintManager()
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|                                     .getSymVal(this, sym)) {
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|         // FIXME: Because we don't correctly model (yet) sign-extension
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|         // and truncation of symbolic values, we need to convert
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|         // the integer value to the correct signedness and bitwidth.
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|         //
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|         // This shows up in the following:
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|         //
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|         //   char foo();
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|         //   unsigned x = foo();
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|         //   if (x == 54)
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|         //     ...
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|         //
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|         //  The symbolic value stored to 'x' is actually the conjured
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|         //  symbol for the call to foo(); the type of that symbol is 'char',
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|         //  not unsigned.
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|         const llvm::APSInt &NewV = getBasicVals().Convert(T, *Int);
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| 
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|         if (V.getAs<Loc>())
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|           return loc::ConcreteInt(NewV);
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|         else
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|           return nonloc::ConcreteInt(NewV);
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|       }
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|     }
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|   }
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| 
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|   return V;
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| }
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| 
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| ProgramStateRef ProgramState::BindExpr(const Stmt *S,
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|                                            const LocationContext *LCtx,
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|                                            SVal V, bool Invalidate) const{
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|   Environment NewEnv =
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|     getStateManager().EnvMgr.bindExpr(Env, EnvironmentEntry(S, LCtx), V,
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|                                       Invalidate);
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|   if (NewEnv == Env)
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|     return this;
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| 
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|   ProgramState NewSt = *this;
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|   NewSt.Env = NewEnv;
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|   return getStateManager().getPersistentState(NewSt);
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| }
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| 
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| ProgramStateRef ProgramState::assumeInBound(DefinedOrUnknownSVal Idx,
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|                                       DefinedOrUnknownSVal UpperBound,
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|                                       bool Assumption,
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|                                       QualType indexTy) const {
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|   if (Idx.isUnknown() || UpperBound.isUnknown())
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|     return this;
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| 
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|   // Build an expression for 0 <= Idx < UpperBound.
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|   // This is the same as Idx + MIN < UpperBound + MIN, if overflow is allowed.
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|   // FIXME: This should probably be part of SValBuilder.
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|   ProgramStateManager &SM = getStateManager();
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|   SValBuilder &svalBuilder = SM.getSValBuilder();
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|   ASTContext &Ctx = svalBuilder.getContext();
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| 
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|   // Get the offset: the minimum value of the array index type.
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|   BasicValueFactory &BVF = svalBuilder.getBasicValueFactory();
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|   // FIXME: This should be using ValueManager::ArrayindexTy...somehow.
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|   if (indexTy.isNull())
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|     indexTy = Ctx.IntTy;
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|   nonloc::ConcreteInt Min(BVF.getMinValue(indexTy));
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| 
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|   // Adjust the index.
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|   SVal newIdx = svalBuilder.evalBinOpNN(this, BO_Add,
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|                                         Idx.castAs<NonLoc>(), Min, indexTy);
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|   if (newIdx.isUnknownOrUndef())
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|     return this;
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| 
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|   // Adjust the upper bound.
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|   SVal newBound =
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|     svalBuilder.evalBinOpNN(this, BO_Add, UpperBound.castAs<NonLoc>(),
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|                             Min, indexTy);
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| 
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|   if (newBound.isUnknownOrUndef())
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|     return this;
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| 
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|   // Build the actual comparison.
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|   SVal inBound = svalBuilder.evalBinOpNN(this, BO_LT, newIdx.castAs<NonLoc>(),
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|                                          newBound.castAs<NonLoc>(), Ctx.IntTy);
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|   if (inBound.isUnknownOrUndef())
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|     return this;
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| 
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|   // Finally, let the constraint manager take care of it.
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|   ConstraintManager &CM = SM.getConstraintManager();
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|   return CM.assume(this, inBound.castAs<DefinedSVal>(), Assumption);
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| }
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| 
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| ConditionTruthVal ProgramState::isNull(SVal V) const {
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|   if (V.isZeroConstant())
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|     return true;
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| 
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|   if (V.isConstant())
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|     return false;
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| 
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|   SymbolRef Sym = V.getAsSymbol(/* IncludeBaseRegion */ true);
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|   if (!Sym)
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|     return ConditionTruthVal();
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| 
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|   return getStateManager().ConstraintMgr->isNull(this, Sym);
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| }
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| 
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| ProgramStateRef ProgramStateManager::getInitialState(const LocationContext *InitLoc) {
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|   ProgramState State(this,
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|                 EnvMgr.getInitialEnvironment(),
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|                 StoreMgr->getInitialStore(InitLoc),
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|                 GDMFactory.getEmptyMap());
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| 
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|   return getPersistentState(State);
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| }
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| 
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| ProgramStateRef ProgramStateManager::getPersistentStateWithGDM(
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|                                                      ProgramStateRef FromState,
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|                                                      ProgramStateRef GDMState) {
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|   ProgramState NewState(*FromState);
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|   NewState.GDM = GDMState->GDM;
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|   return getPersistentState(NewState);
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| }
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| 
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| ProgramStateRef ProgramStateManager::getPersistentState(ProgramState &State) {
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| 
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|   llvm::FoldingSetNodeID ID;
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|   State.Profile(ID);
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|   void *InsertPos;
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| 
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|   if (ProgramState *I = StateSet.FindNodeOrInsertPos(ID, InsertPos))
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|     return I;
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| 
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|   ProgramState *newState = nullptr;
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|   if (!freeStates.empty()) {
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|     newState = freeStates.back();
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|     freeStates.pop_back();
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|   }
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|   else {
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|     newState = (ProgramState*) Alloc.Allocate<ProgramState>();
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|   }
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|   new (newState) ProgramState(State);
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|   StateSet.InsertNode(newState, InsertPos);
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|   return newState;
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| }
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| 
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| ProgramStateRef ProgramState::makeWithStore(const StoreRef &store) const {
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|   ProgramState NewSt(*this);
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|   NewSt.setStore(store);
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|   return getStateManager().getPersistentState(NewSt);
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| }
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| 
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| void ProgramState::setStore(const StoreRef &newStore) {
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|   Store newStoreStore = newStore.getStore();
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|   if (newStoreStore)
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|     stateMgr->getStoreManager().incrementReferenceCount(newStoreStore);
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|   if (store)
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|     stateMgr->getStoreManager().decrementReferenceCount(store);
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|   store = newStoreStore;
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| }
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| 
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| //===----------------------------------------------------------------------===//
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| //  State pretty-printing.
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| //===----------------------------------------------------------------------===//
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| 
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| void ProgramState::print(raw_ostream &Out,
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|                          const char *NL, const char *Sep) const {
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|   // Print the store.
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|   ProgramStateManager &Mgr = getStateManager();
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|   Mgr.getStoreManager().print(getStore(), Out, NL, Sep);
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| 
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|   // Print out the environment.
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|   Env.print(Out, NL, Sep);
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| 
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|   // Print out the constraints.
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|   Mgr.getConstraintManager().print(this, Out, NL, Sep);
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| 
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|   // Print checker-specific data.
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|   Mgr.getOwningEngine()->printState(Out, this, NL, Sep);
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| }
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| 
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| void ProgramState::printDOT(raw_ostream &Out) const {
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|   print(Out, "\\l", "\\|");
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| }
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| 
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| void ProgramState::dump() const {
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|   print(llvm::errs());
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| }
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| 
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| void ProgramState::printTaint(raw_ostream &Out,
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|                               const char *NL, const char *Sep) const {
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|   TaintMapImpl TM = get<TaintMap>();
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| 
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|   if (!TM.isEmpty())
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|     Out <<"Tainted Symbols:" << NL;
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| 
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|   for (TaintMapImpl::iterator I = TM.begin(), E = TM.end(); I != E; ++I) {
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|     Out << I->first << " : " << I->second << NL;
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|   }
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| }
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| 
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| void ProgramState::dumpTaint() const {
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|   printTaint(llvm::errs());
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| }
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| 
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| //===----------------------------------------------------------------------===//
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| // Generic Data Map.
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| //===----------------------------------------------------------------------===//
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| 
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| void *const* ProgramState::FindGDM(void *K) const {
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|   return GDM.lookup(K);
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| }
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| 
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| void*
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| ProgramStateManager::FindGDMContext(void *K,
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|                                void *(*CreateContext)(llvm::BumpPtrAllocator&),
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|                                void (*DeleteContext)(void*)) {
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| 
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|   std::pair<void*, void (*)(void*)>& p = GDMContexts[K];
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|   if (!p.first) {
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|     p.first = CreateContext(Alloc);
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|     p.second = DeleteContext;
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|   }
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| 
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|   return p.first;
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| }
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| 
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| ProgramStateRef ProgramStateManager::addGDM(ProgramStateRef St, void *Key, void *Data){
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|   ProgramState::GenericDataMap M1 = St->getGDM();
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|   ProgramState::GenericDataMap M2 = GDMFactory.add(M1, Key, Data);
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| 
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|   if (M1 == M2)
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|     return St;
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| 
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|   ProgramState NewSt = *St;
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|   NewSt.GDM = M2;
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|   return getPersistentState(NewSt);
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| }
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| 
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| ProgramStateRef ProgramStateManager::removeGDM(ProgramStateRef state, void *Key) {
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|   ProgramState::GenericDataMap OldM = state->getGDM();
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|   ProgramState::GenericDataMap NewM = GDMFactory.remove(OldM, Key);
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| 
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|   if (NewM == OldM)
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|     return state;
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| 
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|   ProgramState NewState = *state;
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|   NewState.GDM = NewM;
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|   return getPersistentState(NewState);
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| }
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| 
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| bool ScanReachableSymbols::scan(nonloc::LazyCompoundVal val) {
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|   bool wasVisited = !visited.insert(val.getCVData()).second;
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|   if (wasVisited)
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|     return true;
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| 
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|   StoreManager &StoreMgr = state->getStateManager().getStoreManager();
 | |
|   // FIXME: We don't really want to use getBaseRegion() here because pointer
 | |
|   // arithmetic doesn't apply, but scanReachableSymbols only accepts base
 | |
|   // regions right now.
 | |
|   const MemRegion *R = val.getRegion()->getBaseRegion();
 | |
|   return StoreMgr.scanReachableSymbols(val.getStore(), R, *this);
 | |
| }
 | |
| 
 | |
| bool ScanReachableSymbols::scan(nonloc::CompoundVal val) {
 | |
|   for (nonloc::CompoundVal::iterator I=val.begin(), E=val.end(); I!=E; ++I)
 | |
|     if (!scan(*I))
 | |
|       return false;
 | |
| 
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| bool ScanReachableSymbols::scan(const SymExpr *sym) {
 | |
|   bool wasVisited = !visited.insert(sym).second;
 | |
|   if (wasVisited)
 | |
|     return true;
 | |
| 
 | |
|   if (!visitor.VisitSymbol(sym))
 | |
|     return false;
 | |
| 
 | |
|   // TODO: should be rewritten using SymExpr::symbol_iterator.
 | |
|   switch (sym->getKind()) {
 | |
|     case SymExpr::RegionValueKind:
 | |
|     case SymExpr::ConjuredKind:
 | |
|     case SymExpr::DerivedKind:
 | |
|     case SymExpr::ExtentKind:
 | |
|     case SymExpr::MetadataKind:
 | |
|       break;
 | |
|     case SymExpr::CastSymbolKind:
 | |
|       return scan(cast<SymbolCast>(sym)->getOperand());
 | |
|     case SymExpr::SymIntKind:
 | |
|       return scan(cast<SymIntExpr>(sym)->getLHS());
 | |
|     case SymExpr::IntSymKind:
 | |
|       return scan(cast<IntSymExpr>(sym)->getRHS());
 | |
|     case SymExpr::SymSymKind: {
 | |
|       const SymSymExpr *x = cast<SymSymExpr>(sym);
 | |
|       return scan(x->getLHS()) && scan(x->getRHS());
 | |
|     }
 | |
|   }
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| bool ScanReachableSymbols::scan(SVal val) {
 | |
|   if (Optional<loc::MemRegionVal> X = val.getAs<loc::MemRegionVal>())
 | |
|     return scan(X->getRegion());
 | |
| 
 | |
|   if (Optional<nonloc::LazyCompoundVal> X =
 | |
|           val.getAs<nonloc::LazyCompoundVal>())
 | |
|     return scan(*X);
 | |
| 
 | |
|   if (Optional<nonloc::LocAsInteger> X = val.getAs<nonloc::LocAsInteger>())
 | |
|     return scan(X->getLoc());
 | |
| 
 | |
|   if (SymbolRef Sym = val.getAsSymbol())
 | |
|     return scan(Sym);
 | |
| 
 | |
|   if (const SymExpr *Sym = val.getAsSymbolicExpression())
 | |
|     return scan(Sym);
 | |
| 
 | |
|   if (Optional<nonloc::CompoundVal> X = val.getAs<nonloc::CompoundVal>())
 | |
|     return scan(*X);
 | |
| 
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| bool ScanReachableSymbols::scan(const MemRegion *R) {
 | |
|   if (isa<MemSpaceRegion>(R))
 | |
|     return true;
 | |
| 
 | |
|   bool wasVisited = !visited.insert(R).second;
 | |
|   if (wasVisited)
 | |
|     return true;
 | |
| 
 | |
|   if (!visitor.VisitMemRegion(R))
 | |
|     return false;
 | |
| 
 | |
|   // If this is a symbolic region, visit the symbol for the region.
 | |
|   if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R))
 | |
|     if (!visitor.VisitSymbol(SR->getSymbol()))
 | |
|       return false;
 | |
| 
 | |
|   // If this is a subregion, also visit the parent regions.
 | |
|   if (const SubRegion *SR = dyn_cast<SubRegion>(R)) {
 | |
|     const MemRegion *Super = SR->getSuperRegion();
 | |
|     if (!scan(Super))
 | |
|       return false;
 | |
| 
 | |
|     // When we reach the topmost region, scan all symbols in it.
 | |
|     if (isa<MemSpaceRegion>(Super)) {
 | |
|       StoreManager &StoreMgr = state->getStateManager().getStoreManager();
 | |
|       if (!StoreMgr.scanReachableSymbols(state->getStore(), SR, *this))
 | |
|         return false;
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   // Regions captured by a block are also implicitly reachable.
 | |
|   if (const BlockDataRegion *BDR = dyn_cast<BlockDataRegion>(R)) {
 | |
|     BlockDataRegion::referenced_vars_iterator I = BDR->referenced_vars_begin(),
 | |
|                                               E = BDR->referenced_vars_end();
 | |
|     for ( ; I != E; ++I) {
 | |
|       if (!scan(I.getCapturedRegion()))
 | |
|         return false;
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| bool ProgramState::scanReachableSymbols(SVal val, SymbolVisitor& visitor) const {
 | |
|   ScanReachableSymbols S(this, visitor);
 | |
|   return S.scan(val);
 | |
| }
 | |
| 
 | |
| bool ProgramState::scanReachableSymbols(const SVal *I, const SVal *E,
 | |
|                                    SymbolVisitor &visitor) const {
 | |
|   ScanReachableSymbols S(this, visitor);
 | |
|   for ( ; I != E; ++I) {
 | |
|     if (!S.scan(*I))
 | |
|       return false;
 | |
|   }
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| bool ProgramState::scanReachableSymbols(const MemRegion * const *I,
 | |
|                                    const MemRegion * const *E,
 | |
|                                    SymbolVisitor &visitor) const {
 | |
|   ScanReachableSymbols S(this, visitor);
 | |
|   for ( ; I != E; ++I) {
 | |
|     if (!S.scan(*I))
 | |
|       return false;
 | |
|   }
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| ProgramStateRef ProgramState::addTaint(const Stmt *S,
 | |
|                                            const LocationContext *LCtx,
 | |
|                                            TaintTagType Kind) const {
 | |
|   if (const Expr *E = dyn_cast_or_null<Expr>(S))
 | |
|     S = E->IgnoreParens();
 | |
| 
 | |
|   SymbolRef Sym = getSVal(S, LCtx).getAsSymbol();
 | |
|   if (Sym)
 | |
|     return addTaint(Sym, Kind);
 | |
| 
 | |
|   const MemRegion *R = getSVal(S, LCtx).getAsRegion();
 | |
|   addTaint(R, Kind);
 | |
| 
 | |
|   // Cannot add taint, so just return the state.
 | |
|   return this;
 | |
| }
 | |
| 
 | |
| ProgramStateRef ProgramState::addTaint(const MemRegion *R,
 | |
|                                            TaintTagType Kind) const {
 | |
|   if (const SymbolicRegion *SR = dyn_cast_or_null<SymbolicRegion>(R))
 | |
|     return addTaint(SR->getSymbol(), Kind);
 | |
|   return this;
 | |
| }
 | |
| 
 | |
| ProgramStateRef ProgramState::addTaint(SymbolRef Sym,
 | |
|                                            TaintTagType Kind) const {
 | |
|   // If this is a symbol cast, remove the cast before adding the taint. Taint
 | |
|   // is cast agnostic.
 | |
|   while (const SymbolCast *SC = dyn_cast<SymbolCast>(Sym))
 | |
|     Sym = SC->getOperand();
 | |
| 
 | |
|   ProgramStateRef NewState = set<TaintMap>(Sym, Kind);
 | |
|   assert(NewState);
 | |
|   return NewState;
 | |
| }
 | |
| 
 | |
| bool ProgramState::isTainted(const Stmt *S, const LocationContext *LCtx,
 | |
|                              TaintTagType Kind) const {
 | |
|   if (const Expr *E = dyn_cast_or_null<Expr>(S))
 | |
|     S = E->IgnoreParens();
 | |
| 
 | |
|   SVal val = getSVal(S, LCtx);
 | |
|   return isTainted(val, Kind);
 | |
| }
 | |
| 
 | |
| bool ProgramState::isTainted(SVal V, TaintTagType Kind) const {
 | |
|   if (const SymExpr *Sym = V.getAsSymExpr())
 | |
|     return isTainted(Sym, Kind);
 | |
|   if (const MemRegion *Reg = V.getAsRegion())
 | |
|     return isTainted(Reg, Kind);
 | |
|   return false;
 | |
| }
 | |
| 
 | |
| bool ProgramState::isTainted(const MemRegion *Reg, TaintTagType K) const {
 | |
|   if (!Reg)
 | |
|     return false;
 | |
| 
 | |
|   // Element region (array element) is tainted if either the base or the offset
 | |
|   // are tainted.
 | |
|   if (const ElementRegion *ER = dyn_cast<ElementRegion>(Reg))
 | |
|     return isTainted(ER->getSuperRegion(), K) || isTainted(ER->getIndex(), K);
 | |
| 
 | |
|   if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(Reg))
 | |
|     return isTainted(SR->getSymbol(), K);
 | |
| 
 | |
|   if (const SubRegion *ER = dyn_cast<SubRegion>(Reg))
 | |
|     return isTainted(ER->getSuperRegion(), K);
 | |
| 
 | |
|   return false;
 | |
| }
 | |
| 
 | |
| bool ProgramState::isTainted(SymbolRef Sym, TaintTagType Kind) const {
 | |
|   if (!Sym)
 | |
|     return false;
 | |
| 
 | |
|   // Traverse all the symbols this symbol depends on to see if any are tainted.
 | |
|   bool Tainted = false;
 | |
|   for (SymExpr::symbol_iterator SI = Sym->symbol_begin(), SE =Sym->symbol_end();
 | |
|        SI != SE; ++SI) {
 | |
|     if (!isa<SymbolData>(*SI))
 | |
|       continue;
 | |
| 
 | |
|     const TaintTagType *Tag = get<TaintMap>(*SI);
 | |
|     Tainted = (Tag && *Tag == Kind);
 | |
| 
 | |
|     // If this is a SymbolDerived with a tainted parent, it's also tainted.
 | |
|     if (const SymbolDerived *SD = dyn_cast<SymbolDerived>(*SI))
 | |
|       Tainted = Tainted || isTainted(SD->getParentSymbol(), Kind);
 | |
| 
 | |
|     // If memory region is tainted, data is also tainted.
 | |
|     if (const SymbolRegionValue *SRV = dyn_cast<SymbolRegionValue>(*SI))
 | |
|       Tainted = Tainted || isTainted(SRV->getRegion(), Kind);
 | |
| 
 | |
|     // If If this is a SymbolCast from a tainted value, it's also tainted.
 | |
|     if (const SymbolCast *SC = dyn_cast<SymbolCast>(*SI))
 | |
|       Tainted = Tainted || isTainted(SC->getOperand(), Kind);
 | |
| 
 | |
|     if (Tainted)
 | |
|       return true;
 | |
|   }
 | |
| 
 | |
|   return Tainted;
 | |
| }
 | |
| 
 |