1 //=-- ExprEngine.cpp - Path-Sensitive Expression-Level Dataflow ---*- 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 defines a meta-engine for path-sensitive dataflow analysis that
11 // is built on GREngine, but provides the boilerplate to execute transfer
12 // functions and build the ExplodedGraph at the expression level.
14 //===----------------------------------------------------------------------===//
16 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
17 #include "PrettyStackTraceLocationContext.h"
18 #include "clang/AST/CharUnits.h"
19 #include "clang/AST/ParentMap.h"
20 #include "clang/AST/StmtCXX.h"
21 #include "clang/AST/StmtObjC.h"
22 #include "clang/Basic/Builtins.h"
23 #include "clang/Basic/PrettyStackTrace.h"
24 #include "clang/Basic/SourceManager.h"
25 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
26 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
27 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
28 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
29 #include "clang/StaticAnalyzer/Core/PathSensitive/LoopWidening.h"
30 #include "llvm/ADT/Statistic.h"
31 #include "llvm/Support/SaveAndRestore.h"
32 #include "llvm/Support/raw_ostream.h"
35 #include "llvm/Support/GraphWriter.h"
38 using namespace clang;
42 #define DEBUG_TYPE "ExprEngine"
44 STATISTIC(NumRemoveDeadBindings,
45 "The # of times RemoveDeadBindings is called");
46 STATISTIC(NumMaxBlockCountReached,
47 "The # of aborted paths due to reaching the maximum block count in "
48 "a top level function");
49 STATISTIC(NumMaxBlockCountReachedInInlined,
50 "The # of aborted paths due to reaching the maximum block count in "
51 "an inlined function");
52 STATISTIC(NumTimesRetriedWithoutInlining,
53 "The # of times we re-evaluated a call without inlining");
55 typedef std::pair<const CXXBindTemporaryExpr *, const StackFrameContext *>
56 CXXBindTemporaryContext;
58 // Keeps track of whether CXXBindTemporaryExpr nodes have been evaluated.
59 // The StackFrameContext assures that nested calls due to inlined recursive
60 // functions do not interfere.
61 REGISTER_TRAIT_WITH_PROGRAMSTATE(InitializedTemporariesSet,
62 llvm::ImmutableSet<CXXBindTemporaryContext>)
64 //===----------------------------------------------------------------------===//
65 // Engine construction and deletion.
66 //===----------------------------------------------------------------------===//
68 static const char* TagProviderName = "ExprEngine";
70 ExprEngine::ExprEngine(AnalysisManager &mgr, bool gcEnabled,
71 SetOfConstDecls *VisitedCalleesIn,
72 FunctionSummariesTy *FS,
73 InliningModes HowToInlineIn)
75 AnalysisDeclContexts(mgr.getAnalysisDeclContextManager()),
78 StateMgr(getContext(), mgr.getStoreManagerCreator(),
79 mgr.getConstraintManagerCreator(), G.getAllocator(),
81 SymMgr(StateMgr.getSymbolManager()),
82 svalBuilder(StateMgr.getSValBuilder()),
83 currStmtIdx(0), currBldrCtx(nullptr),
84 ObjCNoRet(mgr.getASTContext()),
85 ObjCGCEnabled(gcEnabled), BR(mgr, *this),
86 VisitedCallees(VisitedCalleesIn),
87 HowToInline(HowToInlineIn)
89 unsigned TrimInterval = mgr.options.getGraphTrimInterval();
90 if (TrimInterval != 0) {
91 // Enable eager node reclaimation when constructing the ExplodedGraph.
92 G.enableNodeReclamation(TrimInterval);
96 ExprEngine::~ExprEngine() {
100 //===----------------------------------------------------------------------===//
102 //===----------------------------------------------------------------------===//
104 ProgramStateRef ExprEngine::getInitialState(const LocationContext *InitLoc) {
105 ProgramStateRef state = StateMgr.getInitialState(InitLoc);
106 const Decl *D = InitLoc->getDecl();
109 // FIXME: It would be nice if we had a more general mechanism to add
110 // such preconditions. Some day.
113 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
114 // Precondition: the first argument of 'main' is an integer guaranteed
116 const IdentifierInfo *II = FD->getIdentifier();
117 if (!II || !(II->getName() == "main" && FD->getNumParams() > 0))
120 const ParmVarDecl *PD = FD->getParamDecl(0);
121 QualType T = PD->getType();
122 const BuiltinType *BT = dyn_cast<BuiltinType>(T);
123 if (!BT || !BT->isInteger())
126 const MemRegion *R = state->getRegion(PD, InitLoc);
130 SVal V = state->getSVal(loc::MemRegionVal(R));
131 SVal Constraint_untested = evalBinOp(state, BO_GT, V,
132 svalBuilder.makeZeroVal(T),
133 svalBuilder.getConditionType());
135 Optional<DefinedOrUnknownSVal> Constraint =
136 Constraint_untested.getAs<DefinedOrUnknownSVal>();
141 if (ProgramStateRef newState = state->assume(*Constraint, true))
148 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
149 // Precondition: 'self' is always non-null upon entry to an Objective-C
151 const ImplicitParamDecl *SelfD = MD->getSelfDecl();
152 const MemRegion *R = state->getRegion(SelfD, InitLoc);
153 SVal V = state->getSVal(loc::MemRegionVal(R));
155 if (Optional<Loc> LV = V.getAs<Loc>()) {
156 // Assume that the pointer value in 'self' is non-null.
157 state = state->assume(*LV, true);
158 assert(state && "'self' cannot be null");
162 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
163 if (!MD->isStatic()) {
164 // Precondition: 'this' is always non-null upon entry to the
165 // top-level function. This is our starting assumption for
166 // analyzing an "open" program.
167 const StackFrameContext *SFC = InitLoc->getCurrentStackFrame();
168 if (SFC->getParent() == nullptr) {
169 loc::MemRegionVal L = svalBuilder.getCXXThis(MD, SFC);
170 SVal V = state->getSVal(L);
171 if (Optional<Loc> LV = V.getAs<Loc>()) {
172 state = state->assume(*LV, true);
173 assert(state && "'this' cannot be null");
183 ExprEngine::createTemporaryRegionIfNeeded(ProgramStateRef State,
184 const LocationContext *LC,
186 const Expr *Result) {
187 SVal V = State->getSVal(Ex, LC);
189 // If we don't have an explicit result expression, we're in "if needed"
190 // mode. Only create a region if the current value is a NonLoc.
191 if (!V.getAs<NonLoc>())
195 // We need to create a region no matter what. For sanity, make sure we don't
196 // try to stuff a Loc into a non-pointer temporary region.
197 assert(!V.getAs<Loc>() || Loc::isLocType(Result->getType()) ||
198 Result->getType()->isMemberPointerType());
201 ProgramStateManager &StateMgr = State->getStateManager();
202 MemRegionManager &MRMgr = StateMgr.getRegionManager();
203 StoreManager &StoreMgr = StateMgr.getStoreManager();
205 // MaterializeTemporaryExpr may appear out of place, after a few field and
206 // base-class accesses have been made to the object, even though semantically
207 // it is the whole object that gets materialized and lifetime-extended.
211 // `-MaterializeTemporaryExpr
213 // `-CXXTemporaryObjectExpr
215 // instead of the more natural
218 // `-MaterializeTemporaryExpr
219 // `-CXXTemporaryObjectExpr
221 // Use the usual methods for obtaining the expression of the base object,
222 // and record the adjustments that we need to make to obtain the sub-object
223 // that the whole expression 'Ex' refers to. This trick is usual,
224 // in the sense that CodeGen takes a similar route.
226 SmallVector<const Expr *, 2> CommaLHSs;
227 SmallVector<SubobjectAdjustment, 2> Adjustments;
229 const Expr *Init = Ex->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
231 const TypedValueRegion *TR = nullptr;
232 if (const MaterializeTemporaryExpr *MT =
233 dyn_cast<MaterializeTemporaryExpr>(Result)) {
234 StorageDuration SD = MT->getStorageDuration();
235 // If this object is bound to a reference with static storage duration, we
236 // put it in a different region to prevent "address leakage" warnings.
237 if (SD == SD_Static || SD == SD_Thread)
238 TR = MRMgr.getCXXStaticTempObjectRegion(Init);
241 TR = MRMgr.getCXXTempObjectRegion(Init, LC);
243 SVal Reg = loc::MemRegionVal(TR);
245 // Make the necessary adjustments to obtain the sub-object.
246 for (auto I = Adjustments.rbegin(), E = Adjustments.rend(); I != E; ++I) {
247 const SubobjectAdjustment &Adj = *I;
249 case SubobjectAdjustment::DerivedToBaseAdjustment:
250 Reg = StoreMgr.evalDerivedToBase(Reg, Adj.DerivedToBase.BasePath);
252 case SubobjectAdjustment::FieldAdjustment:
253 Reg = StoreMgr.getLValueField(Adj.Field, Reg);
255 case SubobjectAdjustment::MemberPointerAdjustment:
256 // FIXME: Unimplemented.
257 State->bindDefault(Reg, UnknownVal());
262 // Try to recover some path sensitivity in case we couldn't compute the value.
264 V = getSValBuilder().conjureSymbolVal(Result, LC, TR->getValueType(),
265 currBldrCtx->blockCount());
266 // Bind the value of the expression to the sub-object region, and then bind
267 // the sub-object region to our expression.
268 State = State->bindLoc(Reg, V);
269 State = State->BindExpr(Result, LC, Reg);
273 //===----------------------------------------------------------------------===//
274 // Top-level transfer function logic (Dispatcher).
275 //===----------------------------------------------------------------------===//
277 /// evalAssume - Called by ConstraintManager. Used to call checker-specific
278 /// logic for handling assumptions on symbolic values.
279 ProgramStateRef ExprEngine::processAssume(ProgramStateRef state,
280 SVal cond, bool assumption) {
281 return getCheckerManager().runCheckersForEvalAssume(state, cond, assumption);
285 ExprEngine::processRegionChanges(ProgramStateRef state,
286 const InvalidatedSymbols *invalidated,
287 ArrayRef<const MemRegion *> Explicits,
288 ArrayRef<const MemRegion *> Regions,
289 const CallEvent *Call) {
290 return getCheckerManager().runCheckersForRegionChanges(state, invalidated,
291 Explicits, Regions, Call);
294 void ExprEngine::printState(raw_ostream &Out, ProgramStateRef State,
295 const char *NL, const char *Sep) {
296 getCheckerManager().runCheckersForPrintState(Out, State, NL, Sep);
299 void ExprEngine::processEndWorklist(bool hasWorkRemaining) {
300 getCheckerManager().runCheckersForEndAnalysis(G, BR, *this);
303 void ExprEngine::processCFGElement(const CFGElement E, ExplodedNode *Pred,
304 unsigned StmtIdx, NodeBuilderContext *Ctx) {
305 PrettyStackTraceLocationContext CrashInfo(Pred->getLocationContext());
306 currStmtIdx = StmtIdx;
309 switch (E.getKind()) {
310 case CFGElement::Statement:
311 ProcessStmt(const_cast<Stmt*>(E.castAs<CFGStmt>().getStmt()), Pred);
313 case CFGElement::Initializer:
314 ProcessInitializer(E.castAs<CFGInitializer>().getInitializer(), Pred);
316 case CFGElement::NewAllocator:
317 ProcessNewAllocator(E.castAs<CFGNewAllocator>().getAllocatorExpr(),
320 case CFGElement::AutomaticObjectDtor:
321 case CFGElement::DeleteDtor:
322 case CFGElement::BaseDtor:
323 case CFGElement::MemberDtor:
324 case CFGElement::TemporaryDtor:
325 ProcessImplicitDtor(E.castAs<CFGImplicitDtor>(), Pred);
330 static bool shouldRemoveDeadBindings(AnalysisManager &AMgr,
332 const ExplodedNode *Pred,
333 const LocationContext *LC) {
335 // Are we never purging state values?
336 if (AMgr.options.AnalysisPurgeOpt == PurgeNone)
339 // Is this the beginning of a basic block?
340 if (Pred->getLocation().getAs<BlockEntrance>())
343 // Is this on a non-expression?
344 if (!isa<Expr>(S.getStmt()))
347 // Run before processing a call.
348 if (CallEvent::isCallStmt(S.getStmt()))
351 // Is this an expression that is consumed by another expression? If so,
352 // postpone cleaning out the state.
353 ParentMap &PM = LC->getAnalysisDeclContext()->getParentMap();
354 return !PM.isConsumedExpr(cast<Expr>(S.getStmt()));
357 void ExprEngine::removeDead(ExplodedNode *Pred, ExplodedNodeSet &Out,
358 const Stmt *ReferenceStmt,
359 const LocationContext *LC,
360 const Stmt *DiagnosticStmt,
361 ProgramPoint::Kind K) {
362 assert((K == ProgramPoint::PreStmtPurgeDeadSymbolsKind ||
363 ReferenceStmt == nullptr || isa<ReturnStmt>(ReferenceStmt))
364 && "PostStmt is not generally supported by the SymbolReaper yet");
365 assert(LC && "Must pass the current (or expiring) LocationContext");
367 if (!DiagnosticStmt) {
368 DiagnosticStmt = ReferenceStmt;
369 assert(DiagnosticStmt && "Required for clearing a LocationContext");
372 NumRemoveDeadBindings++;
373 ProgramStateRef CleanedState = Pred->getState();
375 // LC is the location context being destroyed, but SymbolReaper wants a
376 // location context that is still live. (If this is the top-level stack
377 // frame, this will be null.)
378 if (!ReferenceStmt) {
379 assert(K == ProgramPoint::PostStmtPurgeDeadSymbolsKind &&
380 "Use PostStmtPurgeDeadSymbolsKind for clearing a LocationContext");
381 LC = LC->getParent();
384 const StackFrameContext *SFC = LC ? LC->getCurrentStackFrame() : nullptr;
385 SymbolReaper SymReaper(SFC, ReferenceStmt, SymMgr, getStoreManager());
387 getCheckerManager().runCheckersForLiveSymbols(CleanedState, SymReaper);
389 // Create a state in which dead bindings are removed from the environment
390 // and the store. TODO: The function should just return new env and store,
392 CleanedState = StateMgr.removeDeadBindings(CleanedState, SFC, SymReaper);
394 // Process any special transfer function for dead symbols.
395 // A tag to track convenience transitions, which can be removed at cleanup.
396 static SimpleProgramPointTag cleanupTag(TagProviderName, "Clean Node");
397 if (!SymReaper.hasDeadSymbols()) {
398 // Generate a CleanedNode that has the environment and store cleaned
399 // up. Since no symbols are dead, we can optimize and not clean out
400 // the constraint manager.
401 StmtNodeBuilder Bldr(Pred, Out, *currBldrCtx);
402 Bldr.generateNode(DiagnosticStmt, Pred, CleanedState, &cleanupTag, K);
405 // Call checkers with the non-cleaned state so that they could query the
406 // values of the soon to be dead symbols.
407 ExplodedNodeSet CheckedSet;
408 getCheckerManager().runCheckersForDeadSymbols(CheckedSet, Pred, SymReaper,
409 DiagnosticStmt, *this, K);
411 // For each node in CheckedSet, generate CleanedNodes that have the
412 // environment, the store, and the constraints cleaned up but have the
413 // user-supplied states as the predecessors.
414 StmtNodeBuilder Bldr(CheckedSet, Out, *currBldrCtx);
415 for (ExplodedNodeSet::const_iterator
416 I = CheckedSet.begin(), E = CheckedSet.end(); I != E; ++I) {
417 ProgramStateRef CheckerState = (*I)->getState();
419 // The constraint manager has not been cleaned up yet, so clean up now.
420 CheckerState = getConstraintManager().removeDeadBindings(CheckerState,
423 assert(StateMgr.haveEqualEnvironments(CheckerState, Pred->getState()) &&
424 "Checkers are not allowed to modify the Environment as a part of "
425 "checkDeadSymbols processing.");
426 assert(StateMgr.haveEqualStores(CheckerState, Pred->getState()) &&
427 "Checkers are not allowed to modify the Store as a part of "
428 "checkDeadSymbols processing.");
430 // Create a state based on CleanedState with CheckerState GDM and
431 // generate a transition to that state.
432 ProgramStateRef CleanedCheckerSt =
433 StateMgr.getPersistentStateWithGDM(CleanedState, CheckerState);
434 Bldr.generateNode(DiagnosticStmt, *I, CleanedCheckerSt, &cleanupTag, K);
439 void ExprEngine::ProcessStmt(const CFGStmt S,
440 ExplodedNode *Pred) {
441 // Reclaim any unnecessary nodes in the ExplodedGraph.
442 G.reclaimRecentlyAllocatedNodes();
444 const Stmt *currStmt = S.getStmt();
445 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(),
446 currStmt->getLocStart(),
447 "Error evaluating statement");
449 // Remove dead bindings and symbols.
450 ExplodedNodeSet CleanedStates;
451 if (shouldRemoveDeadBindings(AMgr, S, Pred, Pred->getLocationContext())){
452 removeDead(Pred, CleanedStates, currStmt, Pred->getLocationContext());
454 CleanedStates.Add(Pred);
456 // Visit the statement.
458 for (ExplodedNodeSet::iterator I = CleanedStates.begin(),
459 E = CleanedStates.end(); I != E; ++I) {
460 ExplodedNodeSet DstI;
461 // Visit the statement.
462 Visit(currStmt, *I, DstI);
466 // Enqueue the new nodes onto the work list.
467 Engine.enqueue(Dst, currBldrCtx->getBlock(), currStmtIdx);
470 void ExprEngine::ProcessInitializer(const CFGInitializer Init,
471 ExplodedNode *Pred) {
472 const CXXCtorInitializer *BMI = Init.getInitializer();
474 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(),
475 BMI->getSourceLocation(),
476 "Error evaluating initializer");
478 // We don't clean up dead bindings here.
479 const StackFrameContext *stackFrame =
480 cast<StackFrameContext>(Pred->getLocationContext());
481 const CXXConstructorDecl *decl =
482 cast<CXXConstructorDecl>(stackFrame->getDecl());
484 ProgramStateRef State = Pred->getState();
485 SVal thisVal = State->getSVal(svalBuilder.getCXXThis(decl, stackFrame));
487 ExplodedNodeSet Tmp(Pred);
490 // Evaluate the initializer, if necessary
491 if (BMI->isAnyMemberInitializer()) {
492 // Constructors build the object directly in the field,
493 // but non-objects must be copied in from the initializer.
494 if (auto *CtorExpr = findDirectConstructorForCurrentCFGElement()) {
495 assert(BMI->getInit()->IgnoreImplicit() == CtorExpr);
497 // The field was directly constructed, so there is no need to bind.
499 const Expr *Init = BMI->getInit()->IgnoreImplicit();
500 const ValueDecl *Field;
501 if (BMI->isIndirectMemberInitializer()) {
502 Field = BMI->getIndirectMember();
503 FieldLoc = State->getLValue(BMI->getIndirectMember(), thisVal);
505 Field = BMI->getMember();
506 FieldLoc = State->getLValue(BMI->getMember(), thisVal);
510 if (Init->getType()->isArrayType()) {
511 // Handle arrays of trivial type. We can represent this with a
512 // primitive load/copy from the base array region.
513 const ArraySubscriptExpr *ASE;
514 while ((ASE = dyn_cast<ArraySubscriptExpr>(Init)))
515 Init = ASE->getBase()->IgnoreImplicit();
517 SVal LValue = State->getSVal(Init, stackFrame);
518 if (!Field->getType()->isReferenceType())
519 if (Optional<Loc> LValueLoc = LValue.getAs<Loc>())
520 InitVal = State->getSVal(*LValueLoc);
522 // If we fail to get the value for some reason, use a symbolic value.
523 if (InitVal.isUnknownOrUndef()) {
524 SValBuilder &SVB = getSValBuilder();
525 InitVal = SVB.conjureSymbolVal(BMI->getInit(), stackFrame,
527 currBldrCtx->blockCount());
530 InitVal = State->getSVal(BMI->getInit(), stackFrame);
533 assert(Tmp.size() == 1 && "have not generated any new nodes yet");
534 assert(*Tmp.begin() == Pred && "have not generated any new nodes yet");
537 PostInitializer PP(BMI, FieldLoc.getAsRegion(), stackFrame);
538 evalBind(Tmp, Init, Pred, FieldLoc, InitVal, /*isInit=*/true, &PP);
541 assert(BMI->isBaseInitializer() || BMI->isDelegatingInitializer());
542 // We already did all the work when visiting the CXXConstructExpr.
545 // Construct PostInitializer nodes whether the state changed or not,
546 // so that the diagnostics don't get confused.
547 PostInitializer PP(BMI, FieldLoc.getAsRegion(), stackFrame);
549 NodeBuilder Bldr(Tmp, Dst, *currBldrCtx);
550 for (ExplodedNodeSet::iterator I = Tmp.begin(), E = Tmp.end(); I != E; ++I) {
551 ExplodedNode *N = *I;
552 Bldr.generateNode(PP, N->getState(), N);
555 // Enqueue the new nodes onto the work list.
556 Engine.enqueue(Dst, currBldrCtx->getBlock(), currStmtIdx);
559 void ExprEngine::ProcessImplicitDtor(const CFGImplicitDtor D,
560 ExplodedNode *Pred) {
562 switch (D.getKind()) {
563 case CFGElement::AutomaticObjectDtor:
564 ProcessAutomaticObjDtor(D.castAs<CFGAutomaticObjDtor>(), Pred, Dst);
566 case CFGElement::BaseDtor:
567 ProcessBaseDtor(D.castAs<CFGBaseDtor>(), Pred, Dst);
569 case CFGElement::MemberDtor:
570 ProcessMemberDtor(D.castAs<CFGMemberDtor>(), Pred, Dst);
572 case CFGElement::TemporaryDtor:
573 ProcessTemporaryDtor(D.castAs<CFGTemporaryDtor>(), Pred, Dst);
575 case CFGElement::DeleteDtor:
576 ProcessDeleteDtor(D.castAs<CFGDeleteDtor>(), Pred, Dst);
579 llvm_unreachable("Unexpected dtor kind.");
582 // Enqueue the new nodes onto the work list.
583 Engine.enqueue(Dst, currBldrCtx->getBlock(), currStmtIdx);
586 void ExprEngine::ProcessNewAllocator(const CXXNewExpr *NE,
587 ExplodedNode *Pred) {
589 AnalysisManager &AMgr = getAnalysisManager();
590 AnalyzerOptions &Opts = AMgr.options;
591 // TODO: We're not evaluating allocators for all cases just yet as
592 // we're not handling the return value correctly, which causes false
593 // positives when the alpha.cplusplus.NewDeleteLeaks check is on.
594 if (Opts.mayInlineCXXAllocator())
595 VisitCXXNewAllocatorCall(NE, Pred, Dst);
597 NodeBuilder Bldr(Pred, Dst, *currBldrCtx);
598 const LocationContext *LCtx = Pred->getLocationContext();
599 PostImplicitCall PP(NE->getOperatorNew(), NE->getLocStart(), LCtx);
600 Bldr.generateNode(PP, Pred->getState(), Pred);
602 Engine.enqueue(Dst, currBldrCtx->getBlock(), currStmtIdx);
605 void ExprEngine::ProcessAutomaticObjDtor(const CFGAutomaticObjDtor Dtor,
607 ExplodedNodeSet &Dst) {
608 const VarDecl *varDecl = Dtor.getVarDecl();
609 QualType varType = varDecl->getType();
611 ProgramStateRef state = Pred->getState();
612 SVal dest = state->getLValue(varDecl, Pred->getLocationContext());
613 const MemRegion *Region = dest.castAs<loc::MemRegionVal>().getRegion();
615 if (varType->isReferenceType()) {
616 Region = state->getSVal(Region).getAsRegion()->getBaseRegion();
617 varType = cast<TypedValueRegion>(Region)->getValueType();
620 VisitCXXDestructor(varType, Region, Dtor.getTriggerStmt(), /*IsBase=*/ false,
624 void ExprEngine::ProcessDeleteDtor(const CFGDeleteDtor Dtor,
626 ExplodedNodeSet &Dst) {
627 ProgramStateRef State = Pred->getState();
628 const LocationContext *LCtx = Pred->getLocationContext();
629 const CXXDeleteExpr *DE = Dtor.getDeleteExpr();
630 const Stmt *Arg = DE->getArgument();
631 SVal ArgVal = State->getSVal(Arg, LCtx);
633 // If the argument to delete is known to be a null value,
634 // don't run destructor.
635 if (State->isNull(ArgVal).isConstrainedTrue()) {
636 QualType DTy = DE->getDestroyedType();
637 QualType BTy = getContext().getBaseElementType(DTy);
638 const CXXRecordDecl *RD = BTy->getAsCXXRecordDecl();
639 const CXXDestructorDecl *Dtor = RD->getDestructor();
641 PostImplicitCall PP(Dtor, DE->getLocStart(), LCtx);
642 NodeBuilder Bldr(Pred, Dst, *currBldrCtx);
643 Bldr.generateNode(PP, Pred->getState(), Pred);
647 VisitCXXDestructor(DE->getDestroyedType(),
648 ArgVal.getAsRegion(),
649 DE, /*IsBase=*/ false,
653 void ExprEngine::ProcessBaseDtor(const CFGBaseDtor D,
654 ExplodedNode *Pred, ExplodedNodeSet &Dst) {
655 const LocationContext *LCtx = Pred->getLocationContext();
657 const CXXDestructorDecl *CurDtor = cast<CXXDestructorDecl>(LCtx->getDecl());
658 Loc ThisPtr = getSValBuilder().getCXXThis(CurDtor,
659 LCtx->getCurrentStackFrame());
660 SVal ThisVal = Pred->getState()->getSVal(ThisPtr);
662 // Create the base object region.
663 const CXXBaseSpecifier *Base = D.getBaseSpecifier();
664 QualType BaseTy = Base->getType();
665 SVal BaseVal = getStoreManager().evalDerivedToBase(ThisVal, BaseTy,
668 VisitCXXDestructor(BaseTy, BaseVal.castAs<loc::MemRegionVal>().getRegion(),
669 CurDtor->getBody(), /*IsBase=*/ true, Pred, Dst);
672 void ExprEngine::ProcessMemberDtor(const CFGMemberDtor D,
673 ExplodedNode *Pred, ExplodedNodeSet &Dst) {
674 const FieldDecl *Member = D.getFieldDecl();
675 ProgramStateRef State = Pred->getState();
676 const LocationContext *LCtx = Pred->getLocationContext();
678 const CXXDestructorDecl *CurDtor = cast<CXXDestructorDecl>(LCtx->getDecl());
679 Loc ThisVal = getSValBuilder().getCXXThis(CurDtor,
680 LCtx->getCurrentStackFrame());
682 State->getLValue(Member, State->getSVal(ThisVal).castAs<Loc>());
684 VisitCXXDestructor(Member->getType(),
685 FieldVal.castAs<loc::MemRegionVal>().getRegion(),
686 CurDtor->getBody(), /*IsBase=*/false, Pred, Dst);
689 void ExprEngine::ProcessTemporaryDtor(const CFGTemporaryDtor D,
691 ExplodedNodeSet &Dst) {
692 ExplodedNodeSet CleanDtorState;
693 StmtNodeBuilder StmtBldr(Pred, CleanDtorState, *currBldrCtx);
694 ProgramStateRef State = Pred->getState();
695 if (State->contains<InitializedTemporariesSet>(
696 std::make_pair(D.getBindTemporaryExpr(), Pred->getStackFrame()))) {
697 // FIXME: Currently we insert temporary destructors for default parameters,
698 // but we don't insert the constructors.
699 State = State->remove<InitializedTemporariesSet>(
700 std::make_pair(D.getBindTemporaryExpr(), Pred->getStackFrame()));
702 StmtBldr.generateNode(D.getBindTemporaryExpr(), Pred, State);
704 QualType varType = D.getBindTemporaryExpr()->getSubExpr()->getType();
705 // FIXME: Currently CleanDtorState can be empty here due to temporaries being
706 // bound to default parameters.
707 assert(CleanDtorState.size() <= 1);
708 ExplodedNode *CleanPred =
709 CleanDtorState.empty() ? Pred : *CleanDtorState.begin();
710 // FIXME: Inlining of temporary destructors is not supported yet anyway, so
711 // we just put a NULL region for now. This will need to be changed later.
712 VisitCXXDestructor(varType, nullptr, D.getBindTemporaryExpr(),
713 /*IsBase=*/false, CleanPred, Dst);
716 void ExprEngine::processCleanupTemporaryBranch(const CXXBindTemporaryExpr *BTE,
717 NodeBuilderContext &BldCtx,
719 ExplodedNodeSet &Dst,
720 const CFGBlock *DstT,
721 const CFGBlock *DstF) {
722 BranchNodeBuilder TempDtorBuilder(Pred, Dst, BldCtx, DstT, DstF);
723 if (Pred->getState()->contains<InitializedTemporariesSet>(
724 std::make_pair(BTE, Pred->getStackFrame()))) {
725 TempDtorBuilder.markInfeasible(false);
726 TempDtorBuilder.generateNode(Pred->getState(), true, Pred);
728 TempDtorBuilder.markInfeasible(true);
729 TempDtorBuilder.generateNode(Pred->getState(), false, Pred);
733 void ExprEngine::VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *BTE,
734 ExplodedNodeSet &PreVisit,
735 ExplodedNodeSet &Dst) {
736 if (!getAnalysisManager().options.includeTemporaryDtorsInCFG()) {
737 // In case we don't have temporary destructors in the CFG, do not mark
738 // the initialization - we would otherwise never clean it up.
742 StmtNodeBuilder StmtBldr(PreVisit, Dst, *currBldrCtx);
743 for (ExplodedNode *Node : PreVisit) {
744 ProgramStateRef State = Node->getState();
746 if (!State->contains<InitializedTemporariesSet>(
747 std::make_pair(BTE, Node->getStackFrame()))) {
748 // FIXME: Currently the state might already contain the marker due to
749 // incorrect handling of temporaries bound to default parameters; for
750 // those, we currently skip the CXXBindTemporaryExpr but rely on adding
751 // temporary destructor nodes.
752 State = State->add<InitializedTemporariesSet>(
753 std::make_pair(BTE, Node->getStackFrame()));
755 StmtBldr.generateNode(BTE, Node, State);
759 void ExprEngine::Visit(const Stmt *S, ExplodedNode *Pred,
760 ExplodedNodeSet &DstTop) {
761 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(),
763 "Error evaluating statement");
765 StmtNodeBuilder Bldr(Pred, DstTop, *currBldrCtx);
767 assert(!isa<Expr>(S) || S == cast<Expr>(S)->IgnoreParens());
769 switch (S->getStmtClass()) {
770 // C++ and ARC stuff we don't support yet.
771 case Expr::ObjCIndirectCopyRestoreExprClass:
772 case Stmt::CXXDependentScopeMemberExprClass:
773 case Stmt::CXXInheritedCtorInitExprClass:
774 case Stmt::CXXTryStmtClass:
775 case Stmt::CXXTypeidExprClass:
776 case Stmt::CXXUuidofExprClass:
777 case Stmt::CXXFoldExprClass:
778 case Stmt::MSPropertyRefExprClass:
779 case Stmt::MSPropertySubscriptExprClass:
780 case Stmt::CXXUnresolvedConstructExprClass:
781 case Stmt::DependentScopeDeclRefExprClass:
782 case Stmt::ArrayTypeTraitExprClass:
783 case Stmt::ExpressionTraitExprClass:
784 case Stmt::UnresolvedLookupExprClass:
785 case Stmt::UnresolvedMemberExprClass:
786 case Stmt::TypoExprClass:
787 case Stmt::CXXNoexceptExprClass:
788 case Stmt::PackExpansionExprClass:
789 case Stmt::SubstNonTypeTemplateParmPackExprClass:
790 case Stmt::FunctionParmPackExprClass:
791 case Stmt::CoroutineBodyStmtClass:
792 case Stmt::CoawaitExprClass:
793 case Stmt::CoreturnStmtClass:
794 case Stmt::CoyieldExprClass:
795 case Stmt::SEHTryStmtClass:
796 case Stmt::SEHExceptStmtClass:
797 case Stmt::SEHLeaveStmtClass:
798 case Stmt::SEHFinallyStmtClass: {
799 const ExplodedNode *node = Bldr.generateSink(S, Pred, Pred->getState());
800 Engine.addAbortedBlock(node, currBldrCtx->getBlock());
804 case Stmt::ParenExprClass:
805 llvm_unreachable("ParenExprs already handled.");
806 case Stmt::GenericSelectionExprClass:
807 llvm_unreachable("GenericSelectionExprs already handled.");
808 // Cases that should never be evaluated simply because they shouldn't
809 // appear in the CFG.
810 case Stmt::BreakStmtClass:
811 case Stmt::CaseStmtClass:
812 case Stmt::CompoundStmtClass:
813 case Stmt::ContinueStmtClass:
814 case Stmt::CXXForRangeStmtClass:
815 case Stmt::DefaultStmtClass:
816 case Stmt::DoStmtClass:
817 case Stmt::ForStmtClass:
818 case Stmt::GotoStmtClass:
819 case Stmt::IfStmtClass:
820 case Stmt::IndirectGotoStmtClass:
821 case Stmt::LabelStmtClass:
822 case Stmt::NoStmtClass:
823 case Stmt::NullStmtClass:
824 case Stmt::SwitchStmtClass:
825 case Stmt::WhileStmtClass:
826 case Expr::MSDependentExistsStmtClass:
827 case Stmt::CapturedStmtClass:
828 case Stmt::OMPParallelDirectiveClass:
829 case Stmt::OMPSimdDirectiveClass:
830 case Stmt::OMPForDirectiveClass:
831 case Stmt::OMPForSimdDirectiveClass:
832 case Stmt::OMPSectionsDirectiveClass:
833 case Stmt::OMPSectionDirectiveClass:
834 case Stmt::OMPSingleDirectiveClass:
835 case Stmt::OMPMasterDirectiveClass:
836 case Stmt::OMPCriticalDirectiveClass:
837 case Stmt::OMPParallelForDirectiveClass:
838 case Stmt::OMPParallelForSimdDirectiveClass:
839 case Stmt::OMPParallelSectionsDirectiveClass:
840 case Stmt::OMPTaskDirectiveClass:
841 case Stmt::OMPTaskyieldDirectiveClass:
842 case Stmt::OMPBarrierDirectiveClass:
843 case Stmt::OMPTaskwaitDirectiveClass:
844 case Stmt::OMPTaskgroupDirectiveClass:
845 case Stmt::OMPFlushDirectiveClass:
846 case Stmt::OMPOrderedDirectiveClass:
847 case Stmt::OMPAtomicDirectiveClass:
848 case Stmt::OMPTargetDirectiveClass:
849 case Stmt::OMPTargetDataDirectiveClass:
850 case Stmt::OMPTargetEnterDataDirectiveClass:
851 case Stmt::OMPTargetExitDataDirectiveClass:
852 case Stmt::OMPTargetParallelDirectiveClass:
853 case Stmt::OMPTargetParallelForDirectiveClass:
854 case Stmt::OMPTargetUpdateDirectiveClass:
855 case Stmt::OMPTeamsDirectiveClass:
856 case Stmt::OMPCancellationPointDirectiveClass:
857 case Stmt::OMPCancelDirectiveClass:
858 case Stmt::OMPTaskLoopDirectiveClass:
859 case Stmt::OMPTaskLoopSimdDirectiveClass:
860 case Stmt::OMPDistributeDirectiveClass:
861 case Stmt::OMPDistributeParallelForDirectiveClass:
862 case Stmt::OMPDistributeParallelForSimdDirectiveClass:
863 case Stmt::OMPDistributeSimdDirectiveClass:
864 case Stmt::OMPTargetParallelForSimdDirectiveClass:
865 case Stmt::OMPTargetSimdDirectiveClass:
866 case Stmt::OMPTeamsDistributeDirectiveClass:
867 case Stmt::OMPTeamsDistributeSimdDirectiveClass:
868 case Stmt::OMPTeamsDistributeParallelForSimdDirectiveClass:
869 case Stmt::OMPTeamsDistributeParallelForDirectiveClass:
870 case Stmt::OMPTargetTeamsDirectiveClass:
871 case Stmt::OMPTargetTeamsDistributeDirectiveClass:
872 case Stmt::OMPTargetTeamsDistributeParallelForDirectiveClass:
873 case Stmt::OMPTargetTeamsDistributeParallelForSimdDirectiveClass:
874 case Stmt::OMPTargetTeamsDistributeSimdDirectiveClass:
875 llvm_unreachable("Stmt should not be in analyzer evaluation loop");
877 case Stmt::ObjCSubscriptRefExprClass:
878 case Stmt::ObjCPropertyRefExprClass:
879 llvm_unreachable("These are handled by PseudoObjectExpr");
881 case Stmt::GNUNullExprClass: {
882 // GNU __null is a pointer-width integer, not an actual pointer.
883 ProgramStateRef state = Pred->getState();
884 state = state->BindExpr(S, Pred->getLocationContext(),
885 svalBuilder.makeIntValWithPtrWidth(0, false));
886 Bldr.generateNode(S, Pred, state);
890 case Stmt::ObjCAtSynchronizedStmtClass:
891 Bldr.takeNodes(Pred);
892 VisitObjCAtSynchronizedStmt(cast<ObjCAtSynchronizedStmt>(S), Pred, Dst);
896 case Stmt::ExprWithCleanupsClass:
897 // Handled due to fully linearised CFG.
900 case Stmt::CXXBindTemporaryExprClass: {
901 Bldr.takeNodes(Pred);
902 ExplodedNodeSet PreVisit;
903 getCheckerManager().runCheckersForPreStmt(PreVisit, Pred, S, *this);
904 ExplodedNodeSet Next;
905 VisitCXXBindTemporaryExpr(cast<CXXBindTemporaryExpr>(S), PreVisit, Next);
906 getCheckerManager().runCheckersForPostStmt(Dst, Next, S, *this);
911 // Cases not handled yet; but will handle some day.
912 case Stmt::DesignatedInitExprClass:
913 case Stmt::DesignatedInitUpdateExprClass:
914 case Stmt::ArrayInitLoopExprClass:
915 case Stmt::ArrayInitIndexExprClass:
916 case Stmt::ExtVectorElementExprClass:
917 case Stmt::ImaginaryLiteralClass:
918 case Stmt::ObjCAtCatchStmtClass:
919 case Stmt::ObjCAtFinallyStmtClass:
920 case Stmt::ObjCAtTryStmtClass:
921 case Stmt::ObjCAutoreleasePoolStmtClass:
922 case Stmt::ObjCEncodeExprClass:
923 case Stmt::ObjCIsaExprClass:
924 case Stmt::ObjCProtocolExprClass:
925 case Stmt::ObjCSelectorExprClass:
926 case Stmt::ParenListExprClass:
927 case Stmt::ShuffleVectorExprClass:
928 case Stmt::ConvertVectorExprClass:
929 case Stmt::VAArgExprClass:
930 case Stmt::CUDAKernelCallExprClass:
931 case Stmt::OpaqueValueExprClass:
932 case Stmt::AsTypeExprClass:
935 // Cases we intentionally don't evaluate, since they don't need
936 // to be explicitly evaluated.
937 case Stmt::PredefinedExprClass:
938 case Stmt::AddrLabelExprClass:
939 case Stmt::AttributedStmtClass:
940 case Stmt::IntegerLiteralClass:
941 case Stmt::CharacterLiteralClass:
942 case Stmt::ImplicitValueInitExprClass:
943 case Stmt::CXXScalarValueInitExprClass:
944 case Stmt::CXXBoolLiteralExprClass:
945 case Stmt::ObjCBoolLiteralExprClass:
946 case Stmt::ObjCAvailabilityCheckExprClass:
947 case Stmt::FloatingLiteralClass:
948 case Stmt::NoInitExprClass:
949 case Stmt::SizeOfPackExprClass:
950 case Stmt::StringLiteralClass:
951 case Stmt::ObjCStringLiteralClass:
952 case Stmt::CXXPseudoDestructorExprClass:
953 case Stmt::SubstNonTypeTemplateParmExprClass:
954 case Stmt::CXXNullPtrLiteralExprClass:
955 case Stmt::OMPArraySectionExprClass:
956 case Stmt::TypeTraitExprClass: {
957 Bldr.takeNodes(Pred);
958 ExplodedNodeSet preVisit;
959 getCheckerManager().runCheckersForPreStmt(preVisit, Pred, S, *this);
960 getCheckerManager().runCheckersForPostStmt(Dst, preVisit, S, *this);
965 case Stmt::CXXDefaultArgExprClass:
966 case Stmt::CXXDefaultInitExprClass: {
967 Bldr.takeNodes(Pred);
968 ExplodedNodeSet PreVisit;
969 getCheckerManager().runCheckersForPreStmt(PreVisit, Pred, S, *this);
972 StmtNodeBuilder Bldr2(PreVisit, Tmp, *currBldrCtx);
975 if (const CXXDefaultArgExpr *DefE = dyn_cast<CXXDefaultArgExpr>(S))
976 ArgE = DefE->getExpr();
977 else if (const CXXDefaultInitExpr *DefE = dyn_cast<CXXDefaultInitExpr>(S))
978 ArgE = DefE->getExpr();
980 llvm_unreachable("unknown constant wrapper kind");
982 bool IsTemporary = false;
983 if (const MaterializeTemporaryExpr *MTE =
984 dyn_cast<MaterializeTemporaryExpr>(ArgE)) {
985 ArgE = MTE->GetTemporaryExpr();
989 Optional<SVal> ConstantVal = svalBuilder.getConstantVal(ArgE);
991 ConstantVal = UnknownVal();
993 const LocationContext *LCtx = Pred->getLocationContext();
994 for (ExplodedNodeSet::iterator I = PreVisit.begin(), E = PreVisit.end();
996 ProgramStateRef State = (*I)->getState();
997 State = State->BindExpr(S, LCtx, *ConstantVal);
999 State = createTemporaryRegionIfNeeded(State, LCtx,
1002 Bldr2.generateNode(S, *I, State);
1005 getCheckerManager().runCheckersForPostStmt(Dst, Tmp, S, *this);
1010 // Cases we evaluate as opaque expressions, conjuring a symbol.
1011 case Stmt::CXXStdInitializerListExprClass:
1012 case Expr::ObjCArrayLiteralClass:
1013 case Expr::ObjCDictionaryLiteralClass:
1014 case Expr::ObjCBoxedExprClass: {
1015 Bldr.takeNodes(Pred);
1017 ExplodedNodeSet preVisit;
1018 getCheckerManager().runCheckersForPreStmt(preVisit, Pred, S, *this);
1020 ExplodedNodeSet Tmp;
1021 StmtNodeBuilder Bldr2(preVisit, Tmp, *currBldrCtx);
1023 const Expr *Ex = cast<Expr>(S);
1024 QualType resultType = Ex->getType();
1026 for (ExplodedNodeSet::iterator it = preVisit.begin(), et = preVisit.end();
1028 ExplodedNode *N = *it;
1029 const LocationContext *LCtx = N->getLocationContext();
1030 SVal result = svalBuilder.conjureSymbolVal(nullptr, Ex, LCtx,
1032 currBldrCtx->blockCount());
1033 ProgramStateRef state = N->getState()->BindExpr(Ex, LCtx, result);
1034 Bldr2.generateNode(S, N, state);
1037 getCheckerManager().runCheckersForPostStmt(Dst, Tmp, S, *this);
1042 case Stmt::ArraySubscriptExprClass:
1043 Bldr.takeNodes(Pred);
1044 VisitLvalArraySubscriptExpr(cast<ArraySubscriptExpr>(S), Pred, Dst);
1048 case Stmt::GCCAsmStmtClass:
1049 Bldr.takeNodes(Pred);
1050 VisitGCCAsmStmt(cast<GCCAsmStmt>(S), Pred, Dst);
1054 case Stmt::MSAsmStmtClass:
1055 Bldr.takeNodes(Pred);
1056 VisitMSAsmStmt(cast<MSAsmStmt>(S), Pred, Dst);
1060 case Stmt::BlockExprClass:
1061 Bldr.takeNodes(Pred);
1062 VisitBlockExpr(cast<BlockExpr>(S), Pred, Dst);
1066 case Stmt::LambdaExprClass:
1067 if (AMgr.options.shouldInlineLambdas()) {
1068 Bldr.takeNodes(Pred);
1069 VisitLambdaExpr(cast<LambdaExpr>(S), Pred, Dst);
1072 const ExplodedNode *node = Bldr.generateSink(S, Pred, Pred->getState());
1073 Engine.addAbortedBlock(node, currBldrCtx->getBlock());
1077 case Stmt::BinaryOperatorClass: {
1078 const BinaryOperator* B = cast<BinaryOperator>(S);
1079 if (B->isLogicalOp()) {
1080 Bldr.takeNodes(Pred);
1081 VisitLogicalExpr(B, Pred, Dst);
1085 else if (B->getOpcode() == BO_Comma) {
1086 ProgramStateRef state = Pred->getState();
1087 Bldr.generateNode(B, Pred,
1088 state->BindExpr(B, Pred->getLocationContext(),
1089 state->getSVal(B->getRHS(),
1090 Pred->getLocationContext())));
1094 Bldr.takeNodes(Pred);
1096 if (AMgr.options.eagerlyAssumeBinOpBifurcation &&
1097 (B->isRelationalOp() || B->isEqualityOp())) {
1098 ExplodedNodeSet Tmp;
1099 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Tmp);
1100 evalEagerlyAssumeBinOpBifurcation(Dst, Tmp, cast<Expr>(S));
1103 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Dst);
1109 case Stmt::CXXOperatorCallExprClass: {
1110 const CXXOperatorCallExpr *OCE = cast<CXXOperatorCallExpr>(S);
1112 // For instance method operators, make sure the 'this' argument has a
1114 const Decl *Callee = OCE->getCalleeDecl();
1115 if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Callee)) {
1116 if (MD->isInstance()) {
1117 ProgramStateRef State = Pred->getState();
1118 const LocationContext *LCtx = Pred->getLocationContext();
1119 ProgramStateRef NewState =
1120 createTemporaryRegionIfNeeded(State, LCtx, OCE->getArg(0));
1121 if (NewState != State) {
1122 Pred = Bldr.generateNode(OCE, Pred, NewState, /*Tag=*/nullptr,
1123 ProgramPoint::PreStmtKind);
1124 // Did we cache out?
1132 case Stmt::CallExprClass:
1133 case Stmt::CXXMemberCallExprClass:
1134 case Stmt::UserDefinedLiteralClass: {
1135 Bldr.takeNodes(Pred);
1136 VisitCallExpr(cast<CallExpr>(S), Pred, Dst);
1141 case Stmt::CXXCatchStmtClass: {
1142 Bldr.takeNodes(Pred);
1143 VisitCXXCatchStmt(cast<CXXCatchStmt>(S), Pred, Dst);
1148 case Stmt::CXXTemporaryObjectExprClass:
1149 case Stmt::CXXConstructExprClass: {
1150 Bldr.takeNodes(Pred);
1151 VisitCXXConstructExpr(cast<CXXConstructExpr>(S), Pred, Dst);
1156 case Stmt::CXXNewExprClass: {
1157 Bldr.takeNodes(Pred);
1158 ExplodedNodeSet PostVisit;
1159 VisitCXXNewExpr(cast<CXXNewExpr>(S), Pred, PostVisit);
1160 getCheckerManager().runCheckersForPostStmt(Dst, PostVisit, S, *this);
1165 case Stmt::CXXDeleteExprClass: {
1166 Bldr.takeNodes(Pred);
1167 ExplodedNodeSet PreVisit;
1168 const CXXDeleteExpr *CDE = cast<CXXDeleteExpr>(S);
1169 getCheckerManager().runCheckersForPreStmt(PreVisit, Pred, S, *this);
1171 for (ExplodedNodeSet::iterator i = PreVisit.begin(),
1172 e = PreVisit.end(); i != e ; ++i)
1173 VisitCXXDeleteExpr(CDE, *i, Dst);
1178 // FIXME: ChooseExpr is really a constant. We need to fix
1179 // the CFG do not model them as explicit control-flow.
1181 case Stmt::ChooseExprClass: { // __builtin_choose_expr
1182 Bldr.takeNodes(Pred);
1183 const ChooseExpr *C = cast<ChooseExpr>(S);
1184 VisitGuardedExpr(C, C->getLHS(), C->getRHS(), Pred, Dst);
1189 case Stmt::CompoundAssignOperatorClass:
1190 Bldr.takeNodes(Pred);
1191 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Dst);
1195 case Stmt::CompoundLiteralExprClass:
1196 Bldr.takeNodes(Pred);
1197 VisitCompoundLiteralExpr(cast<CompoundLiteralExpr>(S), Pred, Dst);
1201 case Stmt::BinaryConditionalOperatorClass:
1202 case Stmt::ConditionalOperatorClass: { // '?' operator
1203 Bldr.takeNodes(Pred);
1204 const AbstractConditionalOperator *C
1205 = cast<AbstractConditionalOperator>(S);
1206 VisitGuardedExpr(C, C->getTrueExpr(), C->getFalseExpr(), Pred, Dst);
1211 case Stmt::CXXThisExprClass:
1212 Bldr.takeNodes(Pred);
1213 VisitCXXThisExpr(cast<CXXThisExpr>(S), Pred, Dst);
1217 case Stmt::DeclRefExprClass: {
1218 Bldr.takeNodes(Pred);
1219 const DeclRefExpr *DE = cast<DeclRefExpr>(S);
1220 VisitCommonDeclRefExpr(DE, DE->getDecl(), Pred, Dst);
1225 case Stmt::DeclStmtClass:
1226 Bldr.takeNodes(Pred);
1227 VisitDeclStmt(cast<DeclStmt>(S), Pred, Dst);
1231 case Stmt::ImplicitCastExprClass:
1232 case Stmt::CStyleCastExprClass:
1233 case Stmt::CXXStaticCastExprClass:
1234 case Stmt::CXXDynamicCastExprClass:
1235 case Stmt::CXXReinterpretCastExprClass:
1236 case Stmt::CXXConstCastExprClass:
1237 case Stmt::CXXFunctionalCastExprClass:
1238 case Stmt::ObjCBridgedCastExprClass: {
1239 Bldr.takeNodes(Pred);
1240 const CastExpr *C = cast<CastExpr>(S);
1241 ExplodedNodeSet dstExpr;
1242 VisitCast(C, C->getSubExpr(), Pred, dstExpr);
1244 // Handle the postvisit checks.
1245 getCheckerManager().runCheckersForPostStmt(Dst, dstExpr, C, *this);
1250 case Expr::MaterializeTemporaryExprClass: {
1251 Bldr.takeNodes(Pred);
1252 const MaterializeTemporaryExpr *MTE = cast<MaterializeTemporaryExpr>(S);
1253 ExplodedNodeSet dstPrevisit;
1254 getCheckerManager().runCheckersForPreStmt(dstPrevisit, Pred, MTE, *this);
1255 ExplodedNodeSet dstExpr;
1256 for (ExplodedNodeSet::iterator i = dstPrevisit.begin(),
1257 e = dstPrevisit.end(); i != e ; ++i) {
1258 CreateCXXTemporaryObject(MTE, *i, dstExpr);
1260 getCheckerManager().runCheckersForPostStmt(Dst, dstExpr, MTE, *this);
1265 case Stmt::InitListExprClass:
1266 Bldr.takeNodes(Pred);
1267 VisitInitListExpr(cast<InitListExpr>(S), Pred, Dst);
1271 case Stmt::MemberExprClass:
1272 Bldr.takeNodes(Pred);
1273 VisitMemberExpr(cast<MemberExpr>(S), Pred, Dst);
1277 case Stmt::AtomicExprClass:
1278 Bldr.takeNodes(Pred);
1279 VisitAtomicExpr(cast<AtomicExpr>(S), Pred, Dst);
1283 case Stmt::ObjCIvarRefExprClass:
1284 Bldr.takeNodes(Pred);
1285 VisitLvalObjCIvarRefExpr(cast<ObjCIvarRefExpr>(S), Pred, Dst);
1289 case Stmt::ObjCForCollectionStmtClass:
1290 Bldr.takeNodes(Pred);
1291 VisitObjCForCollectionStmt(cast<ObjCForCollectionStmt>(S), Pred, Dst);
1295 case Stmt::ObjCMessageExprClass:
1296 Bldr.takeNodes(Pred);
1297 VisitObjCMessage(cast<ObjCMessageExpr>(S), Pred, Dst);
1301 case Stmt::ObjCAtThrowStmtClass:
1302 case Stmt::CXXThrowExprClass:
1303 // FIXME: This is not complete. We basically treat @throw as
1305 Bldr.generateSink(S, Pred, Pred->getState());
1308 case Stmt::ReturnStmtClass:
1309 Bldr.takeNodes(Pred);
1310 VisitReturnStmt(cast<ReturnStmt>(S), Pred, Dst);
1314 case Stmt::OffsetOfExprClass:
1315 Bldr.takeNodes(Pred);
1316 VisitOffsetOfExpr(cast<OffsetOfExpr>(S), Pred, Dst);
1320 case Stmt::UnaryExprOrTypeTraitExprClass:
1321 Bldr.takeNodes(Pred);
1322 VisitUnaryExprOrTypeTraitExpr(cast<UnaryExprOrTypeTraitExpr>(S),
1327 case Stmt::StmtExprClass: {
1328 const StmtExpr *SE = cast<StmtExpr>(S);
1330 if (SE->getSubStmt()->body_empty()) {
1331 // Empty statement expression.
1332 assert(SE->getType() == getContext().VoidTy
1333 && "Empty statement expression must have void type.");
1337 if (Expr *LastExpr = dyn_cast<Expr>(*SE->getSubStmt()->body_rbegin())) {
1338 ProgramStateRef state = Pred->getState();
1339 Bldr.generateNode(SE, Pred,
1340 state->BindExpr(SE, Pred->getLocationContext(),
1341 state->getSVal(LastExpr,
1342 Pred->getLocationContext())));
1347 case Stmt::UnaryOperatorClass: {
1348 Bldr.takeNodes(Pred);
1349 const UnaryOperator *U = cast<UnaryOperator>(S);
1350 if (AMgr.options.eagerlyAssumeBinOpBifurcation && (U->getOpcode() == UO_LNot)) {
1351 ExplodedNodeSet Tmp;
1352 VisitUnaryOperator(U, Pred, Tmp);
1353 evalEagerlyAssumeBinOpBifurcation(Dst, Tmp, U);
1356 VisitUnaryOperator(U, Pred, Dst);
1361 case Stmt::PseudoObjectExprClass: {
1362 Bldr.takeNodes(Pred);
1363 ProgramStateRef state = Pred->getState();
1364 const PseudoObjectExpr *PE = cast<PseudoObjectExpr>(S);
1365 if (const Expr *Result = PE->getResultExpr()) {
1366 SVal V = state->getSVal(Result, Pred->getLocationContext());
1367 Bldr.generateNode(S, Pred,
1368 state->BindExpr(S, Pred->getLocationContext(), V));
1371 Bldr.generateNode(S, Pred,
1372 state->BindExpr(S, Pred->getLocationContext(),
1381 bool ExprEngine::replayWithoutInlining(ExplodedNode *N,
1382 const LocationContext *CalleeLC) {
1383 const StackFrameContext *CalleeSF = CalleeLC->getCurrentStackFrame();
1384 const StackFrameContext *CallerSF = CalleeSF->getParent()->getCurrentStackFrame();
1385 assert(CalleeSF && CallerSF);
1386 ExplodedNode *BeforeProcessingCall = nullptr;
1387 const Stmt *CE = CalleeSF->getCallSite();
1389 // Find the first node before we started processing the call expression.
1391 ProgramPoint L = N->getLocation();
1392 BeforeProcessingCall = N;
1393 N = N->pred_empty() ? nullptr : *(N->pred_begin());
1395 // Skip the nodes corresponding to the inlined code.
1396 if (L.getLocationContext()->getCurrentStackFrame() != CallerSF)
1398 // We reached the caller. Find the node right before we started
1399 // processing the call.
1400 if (L.isPurgeKind())
1402 if (L.getAs<PreImplicitCall>())
1404 if (L.getAs<CallEnter>())
1406 if (Optional<StmtPoint> SP = L.getAs<StmtPoint>())
1407 if (SP->getStmt() == CE)
1412 if (!BeforeProcessingCall)
1415 // TODO: Clean up the unneeded nodes.
1417 // Build an Epsilon node from which we will restart the analyzes.
1418 // Note that CE is permitted to be NULL!
1419 ProgramPoint NewNodeLoc =
1420 EpsilonPoint(BeforeProcessingCall->getLocationContext(), CE);
1421 // Add the special flag to GDM to signal retrying with no inlining.
1422 // Note, changing the state ensures that we are not going to cache out.
1423 ProgramStateRef NewNodeState = BeforeProcessingCall->getState();
1425 NewNodeState->set<ReplayWithoutInlining>(const_cast<Stmt *>(CE));
1427 // Make the new node a successor of BeforeProcessingCall.
1429 ExplodedNode *NewNode = G.getNode(NewNodeLoc, NewNodeState, false, &IsNew);
1430 // We cached out at this point. Caching out is common due to us backtracking
1431 // from the inlined function, which might spawn several paths.
1435 NewNode->addPredecessor(BeforeProcessingCall, G);
1437 // Add the new node to the work list.
1438 Engine.enqueueStmtNode(NewNode, CalleeSF->getCallSiteBlock(),
1439 CalleeSF->getIndex());
1440 NumTimesRetriedWithoutInlining++;
1444 /// Block entrance. (Update counters).
1445 void ExprEngine::processCFGBlockEntrance(const BlockEdge &L,
1446 NodeBuilderWithSinks &nodeBuilder,
1447 ExplodedNode *Pred) {
1448 PrettyStackTraceLocationContext CrashInfo(Pred->getLocationContext());
1450 // If this block is terminated by a loop and it has already been visited the
1451 // maximum number of times, widen the loop.
1452 unsigned int BlockCount = nodeBuilder.getContext().blockCount();
1453 if (BlockCount == AMgr.options.maxBlockVisitOnPath - 1 &&
1454 AMgr.options.shouldWidenLoops()) {
1455 const Stmt *Term = nodeBuilder.getContext().getBlock()->getTerminator();
1457 (isa<ForStmt>(Term) || isa<WhileStmt>(Term) || isa<DoStmt>(Term))))
1460 const LocationContext *LCtx = Pred->getLocationContext();
1461 ProgramStateRef WidenedState =
1462 getWidenedLoopState(Pred->getState(), LCtx, BlockCount, Term);
1463 nodeBuilder.generateNode(WidenedState, Pred);
1467 // FIXME: Refactor this into a checker.
1468 if (BlockCount >= AMgr.options.maxBlockVisitOnPath) {
1469 static SimpleProgramPointTag tag(TagProviderName, "Block count exceeded");
1470 const ExplodedNode *Sink =
1471 nodeBuilder.generateSink(Pred->getState(), Pred, &tag);
1473 // Check if we stopped at the top level function or not.
1474 // Root node should have the location context of the top most function.
1475 const LocationContext *CalleeLC = Pred->getLocation().getLocationContext();
1476 const LocationContext *CalleeSF = CalleeLC->getCurrentStackFrame();
1477 const LocationContext *RootLC =
1478 (*G.roots_begin())->getLocation().getLocationContext();
1479 if (RootLC->getCurrentStackFrame() != CalleeSF) {
1480 Engine.FunctionSummaries->markReachedMaxBlockCount(CalleeSF->getDecl());
1482 // Re-run the call evaluation without inlining it, by storing the
1483 // no-inlining policy in the state and enqueuing the new work item on
1484 // the list. Replay should almost never fail. Use the stats to catch it
1486 if ((!AMgr.options.NoRetryExhausted &&
1487 replayWithoutInlining(Pred, CalleeLC)))
1489 NumMaxBlockCountReachedInInlined++;
1491 NumMaxBlockCountReached++;
1493 // Make sink nodes as exhausted(for stats) only if retry failed.
1494 Engine.blocksExhausted.push_back(std::make_pair(L, Sink));
1498 //===----------------------------------------------------------------------===//
1499 // Branch processing.
1500 //===----------------------------------------------------------------------===//
1502 /// RecoverCastedSymbol - A helper function for ProcessBranch that is used
1503 /// to try to recover some path-sensitivity for casts of symbolic
1504 /// integers that promote their values (which are currently not tracked well).
1505 /// This function returns the SVal bound to Condition->IgnoreCasts if all the
1506 // cast(s) did was sign-extend the original value.
1507 static SVal RecoverCastedSymbol(ProgramStateManager& StateMgr,
1508 ProgramStateRef state,
1509 const Stmt *Condition,
1510 const LocationContext *LCtx,
1513 const Expr *Ex = dyn_cast<Expr>(Condition);
1515 return UnknownVal();
1518 bool bitsInit = false;
1520 while (const CastExpr *CE = dyn_cast<CastExpr>(Ex)) {
1521 QualType T = CE->getType();
1523 if (!T->isIntegralOrEnumerationType())
1524 return UnknownVal();
1526 uint64_t newBits = Ctx.getTypeSize(T);
1527 if (!bitsInit || newBits < bits) {
1532 Ex = CE->getSubExpr();
1535 // We reached a non-cast. Is it a symbolic value?
1536 QualType T = Ex->getType();
1538 if (!bitsInit || !T->isIntegralOrEnumerationType() ||
1539 Ctx.getTypeSize(T) > bits)
1540 return UnknownVal();
1542 return state->getSVal(Ex, LCtx);
1546 static const Stmt *getRightmostLeaf(const Stmt *Condition) {
1548 const BinaryOperator *BO = dyn_cast<BinaryOperator>(Condition);
1549 if (!BO || !BO->isLogicalOp()) {
1552 Condition = BO->getRHS()->IgnoreParens();
1558 // Returns the condition the branch at the end of 'B' depends on and whose value
1559 // has been evaluated within 'B'.
1560 // In most cases, the terminator condition of 'B' will be evaluated fully in
1561 // the last statement of 'B'; in those cases, the resolved condition is the
1562 // given 'Condition'.
1563 // If the condition of the branch is a logical binary operator tree, the CFG is
1564 // optimized: in that case, we know that the expression formed by all but the
1565 // rightmost leaf of the logical binary operator tree must be true, and thus
1566 // the branch condition is at this point equivalent to the truth value of that
1567 // rightmost leaf; the CFG block thus only evaluates this rightmost leaf
1568 // expression in its final statement. As the full condition in that case was
1569 // not evaluated, and is thus not in the SVal cache, we need to use that leaf
1570 // expression to evaluate the truth value of the condition in the current state
1572 static const Stmt *ResolveCondition(const Stmt *Condition,
1573 const CFGBlock *B) {
1574 if (const Expr *Ex = dyn_cast<Expr>(Condition))
1575 Condition = Ex->IgnoreParens();
1577 const BinaryOperator *BO = dyn_cast<BinaryOperator>(Condition);
1578 if (!BO || !BO->isLogicalOp())
1581 assert(!B->getTerminator().isTemporaryDtorsBranch() &&
1582 "Temporary destructor branches handled by processBindTemporary.");
1584 // For logical operations, we still have the case where some branches
1585 // use the traditional "merge" approach and others sink the branch
1586 // directly into the basic blocks representing the logical operation.
1587 // We need to distinguish between those two cases here.
1589 // The invariants are still shifting, but it is possible that the
1590 // last element in a CFGBlock is not a CFGStmt. Look for the last
1591 // CFGStmt as the value of the condition.
1592 CFGBlock::const_reverse_iterator I = B->rbegin(), E = B->rend();
1593 for (; I != E; ++I) {
1594 CFGElement Elem = *I;
1595 Optional<CFGStmt> CS = Elem.getAs<CFGStmt>();
1598 const Stmt *LastStmt = CS->getStmt();
1599 assert(LastStmt == Condition || LastStmt == getRightmostLeaf(Condition));
1602 llvm_unreachable("could not resolve condition");
1605 void ExprEngine::processBranch(const Stmt *Condition, const Stmt *Term,
1606 NodeBuilderContext& BldCtx,
1608 ExplodedNodeSet &Dst,
1609 const CFGBlock *DstT,
1610 const CFGBlock *DstF) {
1611 assert((!Condition || !isa<CXXBindTemporaryExpr>(Condition)) &&
1612 "CXXBindTemporaryExprs are handled by processBindTemporary.");
1613 const LocationContext *LCtx = Pred->getLocationContext();
1614 PrettyStackTraceLocationContext StackCrashInfo(LCtx);
1615 currBldrCtx = &BldCtx;
1617 // Check for NULL conditions; e.g. "for(;;)"
1619 BranchNodeBuilder NullCondBldr(Pred, Dst, BldCtx, DstT, DstF);
1620 NullCondBldr.markInfeasible(false);
1621 NullCondBldr.generateNode(Pred->getState(), true, Pred);
1625 if (const Expr *Ex = dyn_cast<Expr>(Condition))
1626 Condition = Ex->IgnoreParens();
1628 Condition = ResolveCondition(Condition, BldCtx.getBlock());
1629 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(),
1630 Condition->getLocStart(),
1631 "Error evaluating branch");
1633 ExplodedNodeSet CheckersOutSet;
1634 getCheckerManager().runCheckersForBranchCondition(Condition, CheckersOutSet,
1636 // We generated only sinks.
1637 if (CheckersOutSet.empty())
1640 BranchNodeBuilder builder(CheckersOutSet, Dst, BldCtx, DstT, DstF);
1641 for (NodeBuilder::iterator I = CheckersOutSet.begin(),
1642 E = CheckersOutSet.end(); E != I; ++I) {
1643 ExplodedNode *PredI = *I;
1645 if (PredI->isSink())
1648 ProgramStateRef PrevState = PredI->getState();
1649 SVal X = PrevState->getSVal(Condition, PredI->getLocationContext());
1651 if (X.isUnknownOrUndef()) {
1652 // Give it a chance to recover from unknown.
1653 if (const Expr *Ex = dyn_cast<Expr>(Condition)) {
1654 if (Ex->getType()->isIntegralOrEnumerationType()) {
1655 // Try to recover some path-sensitivity. Right now casts of symbolic
1656 // integers that promote their values are currently not tracked well.
1657 // If 'Condition' is such an expression, try and recover the
1658 // underlying value and use that instead.
1659 SVal recovered = RecoverCastedSymbol(getStateManager(),
1660 PrevState, Condition,
1661 PredI->getLocationContext(),
1664 if (!recovered.isUnknown()) {
1671 // If the condition is still unknown, give up.
1672 if (X.isUnknownOrUndef()) {
1673 builder.generateNode(PrevState, true, PredI);
1674 builder.generateNode(PrevState, false, PredI);
1678 DefinedSVal V = X.castAs<DefinedSVal>();
1680 ProgramStateRef StTrue, StFalse;
1681 std::tie(StTrue, StFalse) = PrevState->assume(V);
1683 // Process the true branch.
1684 if (builder.isFeasible(true)) {
1686 builder.generateNode(StTrue, true, PredI);
1688 builder.markInfeasible(true);
1691 // Process the false branch.
1692 if (builder.isFeasible(false)) {
1694 builder.generateNode(StFalse, false, PredI);
1696 builder.markInfeasible(false);
1699 currBldrCtx = nullptr;
1702 /// The GDM component containing the set of global variables which have been
1703 /// previously initialized with explicit initializers.
1704 REGISTER_TRAIT_WITH_PROGRAMSTATE(InitializedGlobalsSet,
1705 llvm::ImmutableSet<const VarDecl *>)
1707 void ExprEngine::processStaticInitializer(const DeclStmt *DS,
1708 NodeBuilderContext &BuilderCtx,
1710 clang::ento::ExplodedNodeSet &Dst,
1711 const CFGBlock *DstT,
1712 const CFGBlock *DstF) {
1713 PrettyStackTraceLocationContext CrashInfo(Pred->getLocationContext());
1714 currBldrCtx = &BuilderCtx;
1716 const VarDecl *VD = cast<VarDecl>(DS->getSingleDecl());
1717 ProgramStateRef state = Pred->getState();
1718 bool initHasRun = state->contains<InitializedGlobalsSet>(VD);
1719 BranchNodeBuilder builder(Pred, Dst, BuilderCtx, DstT, DstF);
1722 state = state->add<InitializedGlobalsSet>(VD);
1725 builder.generateNode(state, initHasRun, Pred);
1726 builder.markInfeasible(!initHasRun);
1728 currBldrCtx = nullptr;
1731 /// processIndirectGoto - Called by CoreEngine. Used to generate successor
1732 /// nodes by processing the 'effects' of a computed goto jump.
1733 void ExprEngine::processIndirectGoto(IndirectGotoNodeBuilder &builder) {
1735 ProgramStateRef state = builder.getState();
1736 SVal V = state->getSVal(builder.getTarget(), builder.getLocationContext());
1738 // Three possibilities:
1740 // (1) We know the computed label.
1741 // (2) The label is NULL (or some other constant), or Undefined.
1742 // (3) We have no clue about the label. Dispatch to all targets.
1745 typedef IndirectGotoNodeBuilder::iterator iterator;
1747 if (Optional<loc::GotoLabel> LV = V.getAs<loc::GotoLabel>()) {
1748 const LabelDecl *L = LV->getLabel();
1750 for (iterator I = builder.begin(), E = builder.end(); I != E; ++I) {
1751 if (I.getLabel() == L) {
1752 builder.generateNode(I, state);
1757 llvm_unreachable("No block with label.");
1760 if (V.getAs<loc::ConcreteInt>() || V.getAs<UndefinedVal>()) {
1761 // Dispatch to the first target and mark it as a sink.
1762 //ExplodedNode* N = builder.generateNode(builder.begin(), state, true);
1763 // FIXME: add checker visit.
1764 // UndefBranches.insert(N);
1768 // This is really a catch-all. We don't support symbolics yet.
1769 // FIXME: Implement dispatch for symbolic pointers.
1771 for (iterator I=builder.begin(), E=builder.end(); I != E; ++I)
1772 builder.generateNode(I, state);
1776 static bool stackFrameDoesNotContainInitializedTemporaries(ExplodedNode &Pred) {
1777 const StackFrameContext* Frame = Pred.getStackFrame();
1778 const llvm::ImmutableSet<CXXBindTemporaryContext> &Set =
1779 Pred.getState()->get<InitializedTemporariesSet>();
1780 return std::find_if(Set.begin(), Set.end(),
1781 [&](const CXXBindTemporaryContext &Ctx) {
1782 if (Ctx.second == Frame) {
1784 llvm::errs() << "\n";
1786 return Ctx.second == Frame;
1791 void ExprEngine::processBeginOfFunction(NodeBuilderContext &BC,
1793 ExplodedNodeSet &Dst,
1794 const BlockEdge &L) {
1795 SaveAndRestore<const NodeBuilderContext *> NodeContextRAII(currBldrCtx, &BC);
1796 getCheckerManager().runCheckersForBeginFunction(Dst, L, Pred, *this);
1799 /// ProcessEndPath - Called by CoreEngine. Used to generate end-of-path
1800 /// nodes when the control reaches the end of a function.
1801 void ExprEngine::processEndOfFunction(NodeBuilderContext& BC,
1803 const ReturnStmt *RS) {
1804 // FIXME: Assert that stackFrameDoesNotContainInitializedTemporaries(*Pred)).
1805 // We currently cannot enable this assert, as lifetime extended temporaries
1806 // are not modelled correctly.
1807 PrettyStackTraceLocationContext CrashInfo(Pred->getLocationContext());
1808 StateMgr.EndPath(Pred->getState());
1810 ExplodedNodeSet Dst;
1811 if (Pred->getLocationContext()->inTopFrame()) {
1812 // Remove dead symbols.
1813 ExplodedNodeSet AfterRemovedDead;
1814 removeDeadOnEndOfFunction(BC, Pred, AfterRemovedDead);
1817 for (ExplodedNodeSet::iterator I = AfterRemovedDead.begin(),
1818 E = AfterRemovedDead.end(); I != E; ++I) {
1819 getCheckerManager().runCheckersForEndFunction(BC, Dst, *I, *this);
1822 getCheckerManager().runCheckersForEndFunction(BC, Dst, Pred, *this);
1825 Engine.enqueueEndOfFunction(Dst, RS);
1828 /// ProcessSwitch - Called by CoreEngine. Used to generate successor
1829 /// nodes by processing the 'effects' of a switch statement.
1830 void ExprEngine::processSwitch(SwitchNodeBuilder& builder) {
1831 typedef SwitchNodeBuilder::iterator iterator;
1832 ProgramStateRef state = builder.getState();
1833 const Expr *CondE = builder.getCondition();
1834 SVal CondV_untested = state->getSVal(CondE, builder.getLocationContext());
1836 if (CondV_untested.isUndef()) {
1837 //ExplodedNode* N = builder.generateDefaultCaseNode(state, true);
1838 // FIXME: add checker
1839 //UndefBranches.insert(N);
1843 DefinedOrUnknownSVal CondV = CondV_untested.castAs<DefinedOrUnknownSVal>();
1845 ProgramStateRef DefaultSt = state;
1847 iterator I = builder.begin(), EI = builder.end();
1848 bool defaultIsFeasible = I == EI;
1850 for ( ; I != EI; ++I) {
1851 // Successor may be pruned out during CFG construction.
1855 const CaseStmt *Case = I.getCase();
1857 // Evaluate the LHS of the case value.
1858 llvm::APSInt V1 = Case->getLHS()->EvaluateKnownConstInt(getContext());
1859 assert(V1.getBitWidth() == getContext().getTypeSize(CondE->getType()));
1861 // Get the RHS of the case, if it exists.
1863 if (const Expr *E = Case->getRHS())
1864 V2 = E->EvaluateKnownConstInt(getContext());
1868 ProgramStateRef StateCase;
1869 if (Optional<NonLoc> NL = CondV.getAs<NonLoc>())
1870 std::tie(StateCase, DefaultSt) =
1871 DefaultSt->assumeInclusiveRange(*NL, V1, V2);
1873 StateCase = DefaultSt;
1876 builder.generateCaseStmtNode(I, StateCase);
1878 // Now "assume" that the case doesn't match. Add this state
1879 // to the default state (if it is feasible).
1881 defaultIsFeasible = true;
1883 defaultIsFeasible = false;
1888 if (!defaultIsFeasible)
1891 // If we have switch(enum value), the default branch is not
1892 // feasible if all of the enum constants not covered by 'case:' statements
1893 // are not feasible values for the switch condition.
1895 // Note that this isn't as accurate as it could be. Even if there isn't
1896 // a case for a particular enum value as long as that enum value isn't
1897 // feasible then it shouldn't be considered for making 'default:' reachable.
1898 const SwitchStmt *SS = builder.getSwitch();
1899 const Expr *CondExpr = SS->getCond()->IgnoreParenImpCasts();
1900 if (CondExpr->getType()->getAs<EnumType>()) {
1901 if (SS->isAllEnumCasesCovered())
1905 builder.generateDefaultCaseNode(DefaultSt);
1908 //===----------------------------------------------------------------------===//
1909 // Transfer functions: Loads and stores.
1910 //===----------------------------------------------------------------------===//
1912 void ExprEngine::VisitCommonDeclRefExpr(const Expr *Ex, const NamedDecl *D,
1914 ExplodedNodeSet &Dst) {
1915 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
1917 ProgramStateRef state = Pred->getState();
1918 const LocationContext *LCtx = Pred->getLocationContext();
1920 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
1921 // C permits "extern void v", and if you cast the address to a valid type,
1922 // you can even do things with it. We simply pretend
1923 assert(Ex->isGLValue() || VD->getType()->isVoidType());
1924 const LocationContext *LocCtxt = Pred->getLocationContext();
1925 const Decl *D = LocCtxt->getDecl();
1926 const auto *MD = D ? dyn_cast<CXXMethodDecl>(D) : nullptr;
1927 const auto *DeclRefEx = dyn_cast<DeclRefExpr>(Ex);
1930 if (AMgr.options.shouldInlineLambdas() && DeclRefEx &&
1931 DeclRefEx->refersToEnclosingVariableOrCapture() && MD &&
1932 MD->getParent()->isLambda()) {
1933 // Lookup the field of the lambda.
1934 const CXXRecordDecl *CXXRec = MD->getParent();
1935 llvm::DenseMap<const VarDecl *, FieldDecl *> LambdaCaptureFields;
1936 FieldDecl *LambdaThisCaptureField;
1937 CXXRec->getCaptureFields(LambdaCaptureFields, LambdaThisCaptureField);
1938 const FieldDecl *FD = LambdaCaptureFields[VD];
1940 // When a constant is captured, sometimes no corresponding field is
1941 // created in the lambda object.
1942 assert(VD->getType().isConstQualified());
1943 V = state->getLValue(VD, LocCtxt);
1944 IsReference = false;
1947 svalBuilder.getCXXThis(MD, LocCtxt->getCurrentStackFrame());
1948 SVal CXXThisVal = state->getSVal(CXXThis);
1949 V = state->getLValue(FD, CXXThisVal);
1950 IsReference = FD->getType()->isReferenceType();
1953 V = state->getLValue(VD, LocCtxt);
1954 IsReference = VD->getType()->isReferenceType();
1957 // For references, the 'lvalue' is the pointer address stored in the
1958 // reference region.
1960 if (const MemRegion *R = V.getAsRegion())
1961 V = state->getSVal(R);
1966 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), nullptr,
1967 ProgramPoint::PostLValueKind);
1970 if (const EnumConstantDecl *ED = dyn_cast<EnumConstantDecl>(D)) {
1971 assert(!Ex->isGLValue());
1972 SVal V = svalBuilder.makeIntVal(ED->getInitVal());
1973 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V));
1976 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1977 SVal V = svalBuilder.getFunctionPointer(FD);
1978 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), nullptr,
1979 ProgramPoint::PostLValueKind);
1982 if (isa<FieldDecl>(D)) {
1983 // FIXME: Compute lvalue of field pointers-to-member.
1984 // Right now we just use a non-null void pointer, so that it gives proper
1985 // results in boolean contexts.
1986 SVal V = svalBuilder.conjureSymbolVal(Ex, LCtx, getContext().VoidPtrTy,
1987 currBldrCtx->blockCount());
1988 state = state->assume(V.castAs<DefinedOrUnknownSVal>(), true);
1989 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), nullptr,
1990 ProgramPoint::PostLValueKind);
1994 llvm_unreachable("Support for this Decl not implemented.");
1997 /// VisitArraySubscriptExpr - Transfer function for array accesses
1998 void ExprEngine::VisitLvalArraySubscriptExpr(const ArraySubscriptExpr *A,
2000 ExplodedNodeSet &Dst){
2002 const Expr *Base = A->getBase()->IgnoreParens();
2003 const Expr *Idx = A->getIdx()->IgnoreParens();
2005 ExplodedNodeSet CheckerPreStmt;
2006 getCheckerManager().runCheckersForPreStmt(CheckerPreStmt, Pred, A, *this);
2008 ExplodedNodeSet EvalSet;
2009 StmtNodeBuilder Bldr(CheckerPreStmt, EvalSet, *currBldrCtx);
2010 assert(A->isGLValue() ||
2011 (!AMgr.getLangOpts().CPlusPlus &&
2012 A->getType().isCForbiddenLValueType()));
2014 for (auto *Node : CheckerPreStmt) {
2015 const LocationContext *LCtx = Node->getLocationContext();
2016 ProgramStateRef state = Node->getState();
2017 SVal V = state->getLValue(A->getType(),
2018 state->getSVal(Idx, LCtx),
2019 state->getSVal(Base, LCtx));
2020 Bldr.generateNode(A, Node, state->BindExpr(A, LCtx, V), nullptr,
2021 ProgramPoint::PostLValueKind);
2024 getCheckerManager().runCheckersForPostStmt(Dst, EvalSet, A, *this);
2027 /// VisitMemberExpr - Transfer function for member expressions.
2028 void ExprEngine::VisitMemberExpr(const MemberExpr *M, ExplodedNode *Pred,
2029 ExplodedNodeSet &Dst) {
2031 // FIXME: Prechecks eventually go in ::Visit().
2032 ExplodedNodeSet CheckedSet;
2033 getCheckerManager().runCheckersForPreStmt(CheckedSet, Pred, M, *this);
2035 ExplodedNodeSet EvalSet;
2036 ValueDecl *Member = M->getMemberDecl();
2038 // Handle static member variables and enum constants accessed via
2040 if (isa<VarDecl>(Member) || isa<EnumConstantDecl>(Member)) {
2041 ExplodedNodeSet Dst;
2042 for (ExplodedNodeSet::iterator I = CheckedSet.begin(), E = CheckedSet.end();
2044 VisitCommonDeclRefExpr(M, Member, Pred, EvalSet);
2047 StmtNodeBuilder Bldr(CheckedSet, EvalSet, *currBldrCtx);
2048 ExplodedNodeSet Tmp;
2050 for (ExplodedNodeSet::iterator I = CheckedSet.begin(), E = CheckedSet.end();
2052 ProgramStateRef state = (*I)->getState();
2053 const LocationContext *LCtx = (*I)->getLocationContext();
2054 Expr *BaseExpr = M->getBase();
2056 // Handle C++ method calls.
2057 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Member)) {
2058 if (MD->isInstance())
2059 state = createTemporaryRegionIfNeeded(state, LCtx, BaseExpr);
2061 SVal MDVal = svalBuilder.getFunctionPointer(MD);
2062 state = state->BindExpr(M, LCtx, MDVal);
2064 Bldr.generateNode(M, *I, state);
2068 // Handle regular struct fields / member variables.
2069 state = createTemporaryRegionIfNeeded(state, LCtx, BaseExpr);
2070 SVal baseExprVal = state->getSVal(BaseExpr, LCtx);
2072 FieldDecl *field = cast<FieldDecl>(Member);
2073 SVal L = state->getLValue(field, baseExprVal);
2075 if (M->isGLValue() || M->getType()->isArrayType()) {
2076 // We special-case rvalues of array type because the analyzer cannot
2077 // reason about them, since we expect all regions to be wrapped in Locs.
2078 // We instead treat these as lvalues and assume that they will decay to
2079 // pointers as soon as they are used.
2080 if (!M->isGLValue()) {
2081 assert(M->getType()->isArrayType());
2082 const ImplicitCastExpr *PE =
2083 dyn_cast<ImplicitCastExpr>((*I)->getParentMap().getParentIgnoreParens(M));
2084 if (!PE || PE->getCastKind() != CK_ArrayToPointerDecay) {
2085 llvm_unreachable("should always be wrapped in ArrayToPointerDecay");
2089 if (field->getType()->isReferenceType()) {
2090 if (const MemRegion *R = L.getAsRegion())
2091 L = state->getSVal(R);
2096 Bldr.generateNode(M, *I, state->BindExpr(M, LCtx, L), nullptr,
2097 ProgramPoint::PostLValueKind);
2100 evalLoad(Tmp, M, M, *I, state, L);
2106 getCheckerManager().runCheckersForPostStmt(Dst, EvalSet, M, *this);
2109 void ExprEngine::VisitAtomicExpr(const AtomicExpr *AE, ExplodedNode *Pred,
2110 ExplodedNodeSet &Dst) {
2111 ExplodedNodeSet AfterPreSet;
2112 getCheckerManager().runCheckersForPreStmt(AfterPreSet, Pred, AE, *this);
2114 // For now, treat all the arguments to C11 atomics as escaping.
2115 // FIXME: Ideally we should model the behavior of the atomics precisely here.
2117 ExplodedNodeSet AfterInvalidateSet;
2118 StmtNodeBuilder Bldr(AfterPreSet, AfterInvalidateSet, *currBldrCtx);
2120 for (ExplodedNodeSet::iterator I = AfterPreSet.begin(), E = AfterPreSet.end();
2122 ProgramStateRef State = (*I)->getState();
2123 const LocationContext *LCtx = (*I)->getLocationContext();
2125 SmallVector<SVal, 8> ValuesToInvalidate;
2126 for (unsigned SI = 0, Count = AE->getNumSubExprs(); SI != Count; SI++) {
2127 const Expr *SubExpr = AE->getSubExprs()[SI];
2128 SVal SubExprVal = State->getSVal(SubExpr, LCtx);
2129 ValuesToInvalidate.push_back(SubExprVal);
2132 State = State->invalidateRegions(ValuesToInvalidate, AE,
2133 currBldrCtx->blockCount(),
2135 /*CausedByPointerEscape*/true,
2136 /*Symbols=*/nullptr);
2138 SVal ResultVal = UnknownVal();
2139 State = State->BindExpr(AE, LCtx, ResultVal);
2140 Bldr.generateNode(AE, *I, State, nullptr,
2141 ProgramPoint::PostStmtKind);
2144 getCheckerManager().runCheckersForPostStmt(Dst, AfterInvalidateSet, AE, *this);
2148 class CollectReachableSymbolsCallback final : public SymbolVisitor {
2149 InvalidatedSymbols Symbols;
2152 CollectReachableSymbolsCallback(ProgramStateRef State) {}
2153 const InvalidatedSymbols &getSymbols() const { return Symbols; }
2155 bool VisitSymbol(SymbolRef Sym) override {
2156 Symbols.insert(Sym);
2160 } // end anonymous namespace
2162 // A value escapes in three possible cases:
2163 // (1) We are binding to something that is not a memory region.
2164 // (2) We are binding to a MemrRegion that does not have stack storage.
2165 // (3) We are binding to a MemRegion with stack storage that the store
2166 // does not understand.
2167 ProgramStateRef ExprEngine::processPointerEscapedOnBind(ProgramStateRef State,
2168 SVal Loc, SVal Val) {
2169 // Are we storing to something that causes the value to "escape"?
2170 bool escapes = true;
2172 // TODO: Move to StoreManager.
2173 if (Optional<loc::MemRegionVal> regionLoc = Loc.getAs<loc::MemRegionVal>()) {
2174 escapes = !regionLoc->getRegion()->hasStackStorage();
2177 // To test (3), generate a new state with the binding added. If it is
2178 // the same state, then it escapes (since the store cannot represent
2180 // Do this only if we know that the store is not supposed to generate the
2182 SVal StoredVal = State->getSVal(regionLoc->getRegion());
2183 if (StoredVal != Val)
2184 escapes = (State == (State->bindLoc(*regionLoc, Val)));
2188 // If our store can represent the binding and we aren't storing to something
2189 // that doesn't have local storage then just return and have the simulation
2190 // state continue as is.
2194 // Otherwise, find all symbols referenced by 'val' that we are tracking
2195 // and stop tracking them.
2196 CollectReachableSymbolsCallback Scanner =
2197 State->scanReachableSymbols<CollectReachableSymbolsCallback>(Val);
2198 const InvalidatedSymbols &EscapedSymbols = Scanner.getSymbols();
2199 State = getCheckerManager().runCheckersForPointerEscape(State,
2201 /*CallEvent*/ nullptr,
2209 ExprEngine::notifyCheckersOfPointerEscape(ProgramStateRef State,
2210 const InvalidatedSymbols *Invalidated,
2211 ArrayRef<const MemRegion *> ExplicitRegions,
2212 ArrayRef<const MemRegion *> Regions,
2213 const CallEvent *Call,
2214 RegionAndSymbolInvalidationTraits &ITraits) {
2216 if (!Invalidated || Invalidated->empty())
2220 return getCheckerManager().runCheckersForPointerEscape(State,
2226 // If the symbols were invalidated by a call, we want to find out which ones
2227 // were invalidated directly due to being arguments to the call.
2228 InvalidatedSymbols SymbolsDirectlyInvalidated;
2229 for (ArrayRef<const MemRegion *>::iterator I = ExplicitRegions.begin(),
2230 E = ExplicitRegions.end(); I != E; ++I) {
2231 if (const SymbolicRegion *R = (*I)->StripCasts()->getAs<SymbolicRegion>())
2232 SymbolsDirectlyInvalidated.insert(R->getSymbol());
2235 InvalidatedSymbols SymbolsIndirectlyInvalidated;
2236 for (InvalidatedSymbols::const_iterator I=Invalidated->begin(),
2237 E = Invalidated->end(); I!=E; ++I) {
2239 if (SymbolsDirectlyInvalidated.count(sym))
2241 SymbolsIndirectlyInvalidated.insert(sym);
2244 if (!SymbolsDirectlyInvalidated.empty())
2245 State = getCheckerManager().runCheckersForPointerEscape(State,
2246 SymbolsDirectlyInvalidated, Call, PSK_DirectEscapeOnCall, &ITraits);
2248 // Notify about the symbols that get indirectly invalidated by the call.
2249 if (!SymbolsIndirectlyInvalidated.empty())
2250 State = getCheckerManager().runCheckersForPointerEscape(State,
2251 SymbolsIndirectlyInvalidated, Call, PSK_IndirectEscapeOnCall, &ITraits);
2256 /// evalBind - Handle the semantics of binding a value to a specific location.
2257 /// This method is used by evalStore and (soon) VisitDeclStmt, and others.
2258 void ExprEngine::evalBind(ExplodedNodeSet &Dst, const Stmt *StoreE,
2260 SVal location, SVal Val,
2261 bool atDeclInit, const ProgramPoint *PP) {
2263 const LocationContext *LC = Pred->getLocationContext();
2264 PostStmt PS(StoreE, LC);
2268 // Do a previsit of the bind.
2269 ExplodedNodeSet CheckedSet;
2270 getCheckerManager().runCheckersForBind(CheckedSet, Pred, location, Val,
2271 StoreE, *this, *PP);
2273 StmtNodeBuilder Bldr(CheckedSet, Dst, *currBldrCtx);
2275 // If the location is not a 'Loc', it will already be handled by
2276 // the checkers. There is nothing left to do.
2277 if (!location.getAs<Loc>()) {
2278 const ProgramPoint L = PostStore(StoreE, LC, /*Loc*/nullptr,
2280 ProgramStateRef state = Pred->getState();
2281 state = processPointerEscapedOnBind(state, location, Val);
2282 Bldr.generateNode(L, state, Pred);
2286 for (ExplodedNodeSet::iterator I = CheckedSet.begin(), E = CheckedSet.end();
2288 ExplodedNode *PredI = *I;
2289 ProgramStateRef state = PredI->getState();
2291 state = processPointerEscapedOnBind(state, location, Val);
2293 // When binding the value, pass on the hint that this is a initialization.
2294 // For initializations, we do not need to inform clients of region
2296 state = state->bindLoc(location.castAs<Loc>(),
2297 Val, /* notifyChanges = */ !atDeclInit);
2299 const MemRegion *LocReg = nullptr;
2300 if (Optional<loc::MemRegionVal> LocRegVal =
2301 location.getAs<loc::MemRegionVal>()) {
2302 LocReg = LocRegVal->getRegion();
2305 const ProgramPoint L = PostStore(StoreE, LC, LocReg, nullptr);
2306 Bldr.generateNode(L, state, PredI);
2310 /// evalStore - Handle the semantics of a store via an assignment.
2311 /// @param Dst The node set to store generated state nodes
2312 /// @param AssignE The assignment expression if the store happens in an
2314 /// @param LocationE The location expression that is stored to.
2315 /// @param state The current simulation state
2316 /// @param location The location to store the value
2317 /// @param Val The value to be stored
2318 void ExprEngine::evalStore(ExplodedNodeSet &Dst, const Expr *AssignE,
2319 const Expr *LocationE,
2321 ProgramStateRef state, SVal location, SVal Val,
2322 const ProgramPointTag *tag) {
2323 // Proceed with the store. We use AssignE as the anchor for the PostStore
2324 // ProgramPoint if it is non-NULL, and LocationE otherwise.
2325 const Expr *StoreE = AssignE ? AssignE : LocationE;
2327 // Evaluate the location (checks for bad dereferences).
2328 ExplodedNodeSet Tmp;
2329 evalLocation(Tmp, AssignE, LocationE, Pred, state, location, tag, false);
2334 if (location.isUndef())
2337 for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI)
2338 evalBind(Dst, StoreE, *NI, location, Val, false);
2341 void ExprEngine::evalLoad(ExplodedNodeSet &Dst,
2343 const Expr *BoundEx,
2345 ProgramStateRef state,
2347 const ProgramPointTag *tag,
2350 assert(!location.getAs<NonLoc>() && "location cannot be a NonLoc.");
2352 // Are we loading from a region? This actually results in two loads; one
2353 // to fetch the address of the referenced value and one to fetch the
2354 // referenced value.
2355 if (const TypedValueRegion *TR =
2356 dyn_cast_or_null<TypedValueRegion>(location.getAsRegion())) {
2358 QualType ValTy = TR->getValueType();
2359 if (const ReferenceType *RT = ValTy->getAs<ReferenceType>()) {
2360 static SimpleProgramPointTag
2361 loadReferenceTag(TagProviderName, "Load Reference");
2362 ExplodedNodeSet Tmp;
2363 evalLoadCommon(Tmp, NodeEx, BoundEx, Pred, state,
2364 location, &loadReferenceTag,
2365 getContext().getPointerType(RT->getPointeeType()));
2367 // Perform the load from the referenced value.
2368 for (ExplodedNodeSet::iterator I=Tmp.begin(), E=Tmp.end() ; I!=E; ++I) {
2369 state = (*I)->getState();
2370 location = state->getSVal(BoundEx, (*I)->getLocationContext());
2371 evalLoadCommon(Dst, NodeEx, BoundEx, *I, state, location, tag, LoadTy);
2377 evalLoadCommon(Dst, NodeEx, BoundEx, Pred, state, location, tag, LoadTy);
2380 void ExprEngine::evalLoadCommon(ExplodedNodeSet &Dst,
2382 const Expr *BoundEx,
2384 ProgramStateRef state,
2386 const ProgramPointTag *tag,
2390 // Evaluate the location (checks for bad dereferences).
2391 ExplodedNodeSet Tmp;
2392 evalLocation(Tmp, NodeEx, BoundEx, Pred, state, location, tag, true);
2396 StmtNodeBuilder Bldr(Tmp, Dst, *currBldrCtx);
2397 if (location.isUndef())
2400 // Proceed with the load.
2401 for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI) {
2402 state = (*NI)->getState();
2403 const LocationContext *LCtx = (*NI)->getLocationContext();
2405 SVal V = UnknownVal();
2406 if (location.isValid()) {
2407 if (LoadTy.isNull())
2408 LoadTy = BoundEx->getType();
2409 V = state->getSVal(location.castAs<Loc>(), LoadTy);
2412 Bldr.generateNode(NodeEx, *NI, state->BindExpr(BoundEx, LCtx, V), tag,
2413 ProgramPoint::PostLoadKind);
2417 void ExprEngine::evalLocation(ExplodedNodeSet &Dst,
2419 const Stmt *BoundEx,
2421 ProgramStateRef state,
2423 const ProgramPointTag *tag,
2425 StmtNodeBuilder BldrTop(Pred, Dst, *currBldrCtx);
2426 // Early checks for performance reason.
2427 if (location.isUnknown()) {
2431 ExplodedNodeSet Src;
2432 BldrTop.takeNodes(Pred);
2433 StmtNodeBuilder Bldr(Pred, Src, *currBldrCtx);
2434 if (Pred->getState() != state) {
2435 // Associate this new state with an ExplodedNode.
2436 // FIXME: If I pass null tag, the graph is incorrect, e.g for
2440 // "p = 0" is not noted as "Null pointer value stored to 'p'" but
2441 // instead "int *p" is noted as
2442 // "Variable 'p' initialized to a null pointer value"
2444 static SimpleProgramPointTag tag(TagProviderName, "Location");
2445 Bldr.generateNode(NodeEx, Pred, state, &tag);
2447 ExplodedNodeSet Tmp;
2448 getCheckerManager().runCheckersForLocation(Tmp, Src, location, isLoad,
2449 NodeEx, BoundEx, *this);
2450 BldrTop.addNodes(Tmp);
2453 std::pair<const ProgramPointTag *, const ProgramPointTag*>
2454 ExprEngine::geteagerlyAssumeBinOpBifurcationTags() {
2455 static SimpleProgramPointTag
2456 eagerlyAssumeBinOpBifurcationTrue(TagProviderName,
2457 "Eagerly Assume True"),
2458 eagerlyAssumeBinOpBifurcationFalse(TagProviderName,
2459 "Eagerly Assume False");
2460 return std::make_pair(&eagerlyAssumeBinOpBifurcationTrue,
2461 &eagerlyAssumeBinOpBifurcationFalse);
2464 void ExprEngine::evalEagerlyAssumeBinOpBifurcation(ExplodedNodeSet &Dst,
2465 ExplodedNodeSet &Src,
2467 StmtNodeBuilder Bldr(Src, Dst, *currBldrCtx);
2469 for (ExplodedNodeSet::iterator I=Src.begin(), E=Src.end(); I!=E; ++I) {
2470 ExplodedNode *Pred = *I;
2471 // Test if the previous node was as the same expression. This can happen
2472 // when the expression fails to evaluate to anything meaningful and
2473 // (as an optimization) we don't generate a node.
2474 ProgramPoint P = Pred->getLocation();
2475 if (!P.getAs<PostStmt>() || P.castAs<PostStmt>().getStmt() != Ex) {
2479 ProgramStateRef state = Pred->getState();
2480 SVal V = state->getSVal(Ex, Pred->getLocationContext());
2481 Optional<nonloc::SymbolVal> SEV = V.getAs<nonloc::SymbolVal>();
2482 if (SEV && SEV->isExpression()) {
2483 const std::pair<const ProgramPointTag *, const ProgramPointTag*> &tags =
2484 geteagerlyAssumeBinOpBifurcationTags();
2486 ProgramStateRef StateTrue, StateFalse;
2487 std::tie(StateTrue, StateFalse) = state->assume(*SEV);
2489 // First assume that the condition is true.
2491 SVal Val = svalBuilder.makeIntVal(1U, Ex->getType());
2492 StateTrue = StateTrue->BindExpr(Ex, Pred->getLocationContext(), Val);
2493 Bldr.generateNode(Ex, Pred, StateTrue, tags.first);
2496 // Next, assume that the condition is false.
2498 SVal Val = svalBuilder.makeIntVal(0U, Ex->getType());
2499 StateFalse = StateFalse->BindExpr(Ex, Pred->getLocationContext(), Val);
2500 Bldr.generateNode(Ex, Pred, StateFalse, tags.second);
2506 void ExprEngine::VisitGCCAsmStmt(const GCCAsmStmt *A, ExplodedNode *Pred,
2507 ExplodedNodeSet &Dst) {
2508 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
2509 // We have processed both the inputs and the outputs. All of the outputs
2510 // should evaluate to Locs. Nuke all of their values.
2512 // FIXME: Some day in the future it would be nice to allow a "plug-in"
2513 // which interprets the inline asm and stores proper results in the
2516 ProgramStateRef state = Pred->getState();
2518 for (const Expr *O : A->outputs()) {
2519 SVal X = state->getSVal(O, Pred->getLocationContext());
2520 assert (!X.getAs<NonLoc>()); // Should be an Lval, or unknown, undef.
2522 if (Optional<Loc> LV = X.getAs<Loc>())
2523 state = state->bindLoc(*LV, UnknownVal());
2526 Bldr.generateNode(A, Pred, state);
2529 void ExprEngine::VisitMSAsmStmt(const MSAsmStmt *A, ExplodedNode *Pred,
2530 ExplodedNodeSet &Dst) {
2531 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
2532 Bldr.generateNode(A, Pred, Pred->getState());
2535 //===----------------------------------------------------------------------===//
2537 //===----------------------------------------------------------------------===//
2540 static ExprEngine* GraphPrintCheckerState;
2541 static SourceManager* GraphPrintSourceManager;
2545 struct DOTGraphTraits<ExplodedNode*> :
2546 public DefaultDOTGraphTraits {
2548 DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
2550 // FIXME: Since we do not cache error nodes in ExprEngine now, this does not
2552 static std::string getNodeAttributes(const ExplodedNode *N, void*) {
2556 // De-duplicate some source location pretty-printing.
2557 static void printLocation(raw_ostream &Out, SourceLocation SLoc) {
2558 if (SLoc.isFileID()) {
2560 << GraphPrintSourceManager->getExpansionLineNumber(SLoc)
2562 << GraphPrintSourceManager->getExpansionColumnNumber(SLoc)
2566 static void printLocation2(raw_ostream &Out, SourceLocation SLoc) {
2567 if (SLoc.isFileID() && GraphPrintSourceManager->isInMainFile(SLoc))
2568 Out << "line " << GraphPrintSourceManager->getExpansionLineNumber(SLoc);
2570 SLoc.print(Out, *GraphPrintSourceManager);
2573 static std::string getNodeLabel(const ExplodedNode *N, void*){
2576 llvm::raw_string_ostream Out(sbuf);
2578 // Program Location.
2579 ProgramPoint Loc = N->getLocation();
2581 switch (Loc.getKind()) {
2582 case ProgramPoint::BlockEntranceKind: {
2583 Out << "Block Entrance: B"
2584 << Loc.castAs<BlockEntrance>().getBlock()->getBlockID();
2588 case ProgramPoint::BlockExitKind:
2592 case ProgramPoint::CallEnterKind:
2596 case ProgramPoint::CallExitBeginKind:
2597 Out << "CallExitBegin";
2600 case ProgramPoint::CallExitEndKind:
2601 Out << "CallExitEnd";
2604 case ProgramPoint::PostStmtPurgeDeadSymbolsKind:
2605 Out << "PostStmtPurgeDeadSymbols";
2608 case ProgramPoint::PreStmtPurgeDeadSymbolsKind:
2609 Out << "PreStmtPurgeDeadSymbols";
2612 case ProgramPoint::EpsilonKind:
2613 Out << "Epsilon Point";
2616 case ProgramPoint::PreImplicitCallKind: {
2617 ImplicitCallPoint PC = Loc.castAs<ImplicitCallPoint>();
2620 // FIXME: Get proper printing options.
2621 PC.getDecl()->print(Out, LangOptions());
2622 printLocation(Out, PC.getLocation());
2626 case ProgramPoint::PostImplicitCallKind: {
2627 ImplicitCallPoint PC = Loc.castAs<ImplicitCallPoint>();
2628 Out << "PostCall: ";
2630 // FIXME: Get proper printing options.
2631 PC.getDecl()->print(Out, LangOptions());
2632 printLocation(Out, PC.getLocation());
2636 case ProgramPoint::PostInitializerKind: {
2637 Out << "PostInitializer: ";
2638 const CXXCtorInitializer *Init =
2639 Loc.castAs<PostInitializer>().getInitializer();
2640 if (const FieldDecl *FD = Init->getAnyMember())
2643 QualType Ty = Init->getTypeSourceInfo()->getType();
2644 Ty = Ty.getLocalUnqualifiedType();
2645 LangOptions LO; // FIXME.
2651 case ProgramPoint::BlockEdgeKind: {
2652 const BlockEdge &E = Loc.castAs<BlockEdge>();
2653 Out << "Edge: (B" << E.getSrc()->getBlockID() << ", B"
2654 << E.getDst()->getBlockID() << ')';
2656 if (const Stmt *T = E.getSrc()->getTerminator()) {
2657 SourceLocation SLoc = T->getLocStart();
2659 Out << "\\|Terminator: ";
2660 LangOptions LO; // FIXME.
2661 E.getSrc()->printTerminator(Out, LO);
2663 if (SLoc.isFileID()) {
2665 << GraphPrintSourceManager->getExpansionLineNumber(SLoc)
2667 << GraphPrintSourceManager->getExpansionColumnNumber(SLoc);
2670 if (isa<SwitchStmt>(T)) {
2671 const Stmt *Label = E.getDst()->getLabel();
2674 if (const CaseStmt *C = dyn_cast<CaseStmt>(Label)) {
2676 LangOptions LO; // FIXME.
2678 C->getLHS()->printPretty(Out, nullptr, PrintingPolicy(LO));
2680 if (const Stmt *RHS = C->getRHS()) {
2682 RHS->printPretty(Out, nullptr, PrintingPolicy(LO));
2688 assert (isa<DefaultStmt>(Label));
2689 Out << "\\ldefault:";
2693 Out << "\\l(implicit) default:";
2695 else if (isa<IndirectGotoStmt>(T)) {
2699 Out << "\\lCondition: ";
2700 if (*E.getSrc()->succ_begin() == E.getDst())
2713 const Stmt *S = Loc.castAs<StmtPoint>().getStmt();
2714 assert(S != nullptr && "Expecting non-null Stmt");
2716 Out << S->getStmtClassName() << ' ' << (const void*) S << ' ';
2717 LangOptions LO; // FIXME.
2718 S->printPretty(Out, nullptr, PrintingPolicy(LO));
2719 printLocation(Out, S->getLocStart());
2721 if (Loc.getAs<PreStmt>())
2722 Out << "\\lPreStmt\\l;";
2723 else if (Loc.getAs<PostLoad>())
2724 Out << "\\lPostLoad\\l;";
2725 else if (Loc.getAs<PostStore>())
2726 Out << "\\lPostStore\\l";
2727 else if (Loc.getAs<PostLValue>())
2728 Out << "\\lPostLValue\\l";
2734 ProgramStateRef state = N->getState();
2735 Out << "\\|StateID: " << (const void*) state.get()
2736 << " NodeID: " << (const void*) N << "\\|";
2738 // Analysis stack backtrace.
2739 Out << "Location context stack (from current to outer):\\l";
2740 const LocationContext *LC = Loc.getLocationContext();
2742 for (; LC; LC = LC->getParent(), ++Idx) {
2743 Out << Idx << ". (" << (const void *)LC << ") ";
2744 switch (LC->getKind()) {
2745 case LocationContext::StackFrame:
2746 if (const NamedDecl *D = dyn_cast<NamedDecl>(LC->getDecl()))
2747 Out << "Calling " << D->getQualifiedNameAsString();
2749 Out << "Calling anonymous code";
2750 if (const Stmt *S = cast<StackFrameContext>(LC)->getCallSite()) {
2752 printLocation2(Out, S->getLocStart());
2755 case LocationContext::Block:
2756 Out << "Invoking block";
2757 if (const Decl *D = cast<BlockInvocationContext>(LC)->getBlockDecl()) {
2758 Out << " defined at ";
2759 printLocation2(Out, D->getLocStart());
2762 case LocationContext::Scope:
2763 Out << "Entering scope";
2764 // FIXME: Add more info once ScopeContext is activated.
2771 state->printDOT(Out);
2775 if (const ProgramPointTag *tag = Loc.getTag()) {
2776 Out << "\\|Tag: " << tag->getTagDescription();
2782 } // end llvm namespace
2785 void ExprEngine::ViewGraph(bool trim) {
2788 std::vector<const ExplodedNode*> Src;
2790 // Flush any outstanding reports to make sure we cover all the nodes.
2791 // This does not cause them to get displayed.
2792 for (BugReporter::iterator I=BR.begin(), E=BR.end(); I!=E; ++I)
2793 const_cast<BugType*>(*I)->FlushReports(BR);
2795 // Iterate through the reports and get their nodes.
2796 for (BugReporter::EQClasses_iterator
2797 EI = BR.EQClasses_begin(), EE = BR.EQClasses_end(); EI != EE; ++EI) {
2798 ExplodedNode *N = const_cast<ExplodedNode*>(EI->begin()->getErrorNode());
2799 if (N) Src.push_back(N);
2805 GraphPrintCheckerState = this;
2806 GraphPrintSourceManager = &getContext().getSourceManager();
2808 llvm::ViewGraph(*G.roots_begin(), "ExprEngine");
2810 GraphPrintCheckerState = nullptr;
2811 GraphPrintSourceManager = nullptr;
2816 void ExprEngine::ViewGraph(ArrayRef<const ExplodedNode*> Nodes) {
2818 GraphPrintCheckerState = this;
2819 GraphPrintSourceManager = &getContext().getSourceManager();
2821 std::unique_ptr<ExplodedGraph> TrimmedG(G.trim(Nodes));
2823 if (!TrimmedG.get())
2824 llvm::errs() << "warning: Trimmed ExplodedGraph is empty.\n";
2826 llvm::ViewGraph(*TrimmedG->roots_begin(), "TrimmedExprEngine");
2828 GraphPrintCheckerState = nullptr;
2829 GraphPrintSourceManager = nullptr;