ExprEngine.cpp revision c3bf52ced9652f555aa0767bb822ec4c64546212
1//=-- ExprEngine.cpp - Path-Sensitive Expression-Level Dataflow ---*- C++ -*-= 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file defines 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. 13// 14//===----------------------------------------------------------------------===// 15 16#define DEBUG_TYPE "ExprEngine" 17 18#include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h" 19#include "clang/AST/CharUnits.h" 20#include "clang/AST/ParentMap.h" 21#include "clang/AST/StmtCXX.h" 22#include "clang/AST/StmtObjC.h" 23#include "clang/Basic/Builtins.h" 24#include "clang/Basic/PrettyStackTrace.h" 25#include "clang/Basic/SourceManager.h" 26#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" 27#include "clang/StaticAnalyzer/Core/CheckerManager.h" 28#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h" 29#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" 30#include "llvm/ADT/ImmutableList.h" 31#include "llvm/ADT/Statistic.h" 32#include "llvm/Support/raw_ostream.h" 33 34#ifndef NDEBUG 35#include "llvm/Support/GraphWriter.h" 36#endif 37 38using namespace clang; 39using namespace ento; 40using llvm::APSInt; 41 42STATISTIC(NumRemoveDeadBindings, 43 "The # of times RemoveDeadBindings is called"); 44STATISTIC(NumMaxBlockCountReached, 45 "The # of aborted paths due to reaching the maximum block count in " 46 "a top level function"); 47STATISTIC(NumMaxBlockCountReachedInInlined, 48 "The # of aborted paths due to reaching the maximum block count in " 49 "an inlined function"); 50STATISTIC(NumTimesRetriedWithoutInlining, 51 "The # of times we re-evaluated a call without inlining"); 52 53//===----------------------------------------------------------------------===// 54// Engine construction and deletion. 55//===----------------------------------------------------------------------===// 56 57ExprEngine::ExprEngine(AnalysisManager &mgr, bool gcEnabled, 58 SetOfConstDecls *VisitedCalleesIn, 59 FunctionSummariesTy *FS, 60 InliningModes HowToInlineIn) 61 : AMgr(mgr), 62 AnalysisDeclContexts(mgr.getAnalysisDeclContextManager()), 63 Engine(*this, FS), 64 G(Engine.getGraph()), 65 StateMgr(getContext(), mgr.getStoreManagerCreator(), 66 mgr.getConstraintManagerCreator(), G.getAllocator(), 67 this), 68 SymMgr(StateMgr.getSymbolManager()), 69 svalBuilder(StateMgr.getSValBuilder()), 70 currStmtIdx(0), currBldrCtx(0), 71 ObjCNoRet(mgr.getASTContext()), 72 ObjCGCEnabled(gcEnabled), BR(mgr, *this), 73 VisitedCallees(VisitedCalleesIn), 74 HowToInline(HowToInlineIn) 75{ 76 unsigned TrimInterval = mgr.options.getGraphTrimInterval(); 77 if (TrimInterval != 0) { 78 // Enable eager node reclaimation when constructing the ExplodedGraph. 79 G.enableNodeReclamation(TrimInterval); 80 } 81} 82 83ExprEngine::~ExprEngine() { 84 BR.FlushReports(); 85} 86 87//===----------------------------------------------------------------------===// 88// Utility methods. 89//===----------------------------------------------------------------------===// 90 91ProgramStateRef ExprEngine::getInitialState(const LocationContext *InitLoc) { 92 ProgramStateRef state = StateMgr.getInitialState(InitLoc); 93 const Decl *D = InitLoc->getDecl(); 94 95 // Preconditions. 96 // FIXME: It would be nice if we had a more general mechanism to add 97 // such preconditions. Some day. 98 do { 99 100 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 101 // Precondition: the first argument of 'main' is an integer guaranteed 102 // to be > 0. 103 const IdentifierInfo *II = FD->getIdentifier(); 104 if (!II || !(II->getName() == "main" && FD->getNumParams() > 0)) 105 break; 106 107 const ParmVarDecl *PD = FD->getParamDecl(0); 108 QualType T = PD->getType(); 109 const BuiltinType *BT = dyn_cast<BuiltinType>(T); 110 if (!BT || !BT->isInteger()) 111 break; 112 113 const MemRegion *R = state->getRegion(PD, InitLoc); 114 if (!R) 115 break; 116 117 SVal V = state->getSVal(loc::MemRegionVal(R)); 118 SVal Constraint_untested = evalBinOp(state, BO_GT, V, 119 svalBuilder.makeZeroVal(T), 120 getContext().IntTy); 121 122 Optional<DefinedOrUnknownSVal> Constraint = 123 Constraint_untested.getAs<DefinedOrUnknownSVal>(); 124 125 if (!Constraint) 126 break; 127 128 if (ProgramStateRef newState = state->assume(*Constraint, true)) 129 state = newState; 130 } 131 break; 132 } 133 while (0); 134 135 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 136 // Precondition: 'self' is always non-null upon entry to an Objective-C 137 // method. 138 const ImplicitParamDecl *SelfD = MD->getSelfDecl(); 139 const MemRegion *R = state->getRegion(SelfD, InitLoc); 140 SVal V = state->getSVal(loc::MemRegionVal(R)); 141 142 if (Optional<Loc> LV = V.getAs<Loc>()) { 143 // Assume that the pointer value in 'self' is non-null. 144 state = state->assume(*LV, true); 145 assert(state && "'self' cannot be null"); 146 } 147 } 148 149 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 150 if (!MD->isStatic()) { 151 // Precondition: 'this' is always non-null upon entry to the 152 // top-level function. This is our starting assumption for 153 // analyzing an "open" program. 154 const StackFrameContext *SFC = InitLoc->getCurrentStackFrame(); 155 if (SFC->getParent() == 0) { 156 loc::MemRegionVal L = svalBuilder.getCXXThis(MD, SFC); 157 SVal V = state->getSVal(L); 158 if (Optional<Loc> LV = V.getAs<Loc>()) { 159 state = state->assume(*LV, true); 160 assert(state && "'this' cannot be null"); 161 } 162 } 163 } 164 } 165 166 return state; 167} 168 169ProgramStateRef 170ExprEngine::createTemporaryRegionIfNeeded(ProgramStateRef State, 171 const LocationContext *LC, 172 const Expr *Ex, 173 const Expr *Result) { 174 SVal V = State->getSVal(Ex, LC); 175 if (!Result) { 176 // If we don't have an explicit result expression, we're in "if needed" 177 // mode. Only create a region if the current value is a NonLoc. 178 if (!V.getAs<NonLoc>()) 179 return State; 180 Result = Ex; 181 } else { 182 // We need to create a region no matter what. For sanity, make sure we don't 183 // try to stuff a Loc into a non-pointer temporary region. 184 assert(!V.getAs<Loc>() || Loc::isLocType(Result->getType()) || 185 Result->getType()->isMemberPointerType()); 186 } 187 188 ProgramStateManager &StateMgr = State->getStateManager(); 189 MemRegionManager &MRMgr = StateMgr.getRegionManager(); 190 StoreManager &StoreMgr = StateMgr.getStoreManager(); 191 192 // We need to be careful about treating a derived type's value as 193 // bindings for a base type. Unless we're creating a temporary pointer region, 194 // start by stripping and recording base casts. 195 SmallVector<const CastExpr *, 4> Casts; 196 const Expr *Inner = Ex->IgnoreParens(); 197 if (!Loc::isLocType(Result->getType())) { 198 while (const CastExpr *CE = dyn_cast<CastExpr>(Inner)) { 199 if (CE->getCastKind() == CK_DerivedToBase || 200 CE->getCastKind() == CK_UncheckedDerivedToBase) 201 Casts.push_back(CE); 202 else if (CE->getCastKind() != CK_NoOp) 203 break; 204 205 Inner = CE->getSubExpr()->IgnoreParens(); 206 } 207 } 208 209 // Create a temporary object region for the inner expression (which may have 210 // a more derived type) and bind the value into it. 211 const TypedValueRegion *TR = MRMgr.getCXXTempObjectRegion(Inner, LC); 212 SVal Reg = loc::MemRegionVal(TR); 213 214 if (V.isUnknown()) 215 V = getSValBuilder().conjureSymbolVal(Result, LC, TR->getValueType(), 216 currBldrCtx->blockCount()); 217 State = State->bindLoc(Reg, V); 218 219 // Re-apply the casts (from innermost to outermost) for type sanity. 220 for (SmallVectorImpl<const CastExpr *>::reverse_iterator I = Casts.rbegin(), 221 E = Casts.rend(); 222 I != E; ++I) { 223 Reg = StoreMgr.evalDerivedToBase(Reg, *I); 224 } 225 226 State = State->BindExpr(Result, LC, Reg); 227 return State; 228} 229 230//===----------------------------------------------------------------------===// 231// Top-level transfer function logic (Dispatcher). 232//===----------------------------------------------------------------------===// 233 234/// evalAssume - Called by ConstraintManager. Used to call checker-specific 235/// logic for handling assumptions on symbolic values. 236ProgramStateRef ExprEngine::processAssume(ProgramStateRef state, 237 SVal cond, bool assumption) { 238 return getCheckerManager().runCheckersForEvalAssume(state, cond, assumption); 239} 240 241bool ExprEngine::wantsRegionChangeUpdate(ProgramStateRef state) { 242 return getCheckerManager().wantsRegionChangeUpdate(state); 243} 244 245ProgramStateRef 246ExprEngine::processRegionChanges(ProgramStateRef state, 247 const InvalidatedSymbols *invalidated, 248 ArrayRef<const MemRegion *> Explicits, 249 ArrayRef<const MemRegion *> Regions, 250 const CallEvent *Call) { 251 return getCheckerManager().runCheckersForRegionChanges(state, invalidated, 252 Explicits, Regions, Call); 253} 254 255void ExprEngine::printState(raw_ostream &Out, ProgramStateRef State, 256 const char *NL, const char *Sep) { 257 getCheckerManager().runCheckersForPrintState(Out, State, NL, Sep); 258} 259 260void ExprEngine::processEndWorklist(bool hasWorkRemaining) { 261 getCheckerManager().runCheckersForEndAnalysis(G, BR, *this); 262} 263 264void ExprEngine::processCFGElement(const CFGElement E, ExplodedNode *Pred, 265 unsigned StmtIdx, NodeBuilderContext *Ctx) { 266 currStmtIdx = StmtIdx; 267 currBldrCtx = Ctx; 268 269 switch (E.getKind()) { 270 case CFGElement::Statement: 271 ProcessStmt(const_cast<Stmt*>(E.castAs<CFGStmt>().getStmt()), Pred); 272 return; 273 case CFGElement::Initializer: 274 ProcessInitializer(E.castAs<CFGInitializer>().getInitializer(), Pred); 275 return; 276 case CFGElement::AutomaticObjectDtor: 277 case CFGElement::BaseDtor: 278 case CFGElement::MemberDtor: 279 case CFGElement::TemporaryDtor: 280 ProcessImplicitDtor(E.castAs<CFGImplicitDtor>(), Pred); 281 return; 282 } 283 currBldrCtx = 0; 284} 285 286static bool shouldRemoveDeadBindings(AnalysisManager &AMgr, 287 const CFGStmt S, 288 const ExplodedNode *Pred, 289 const LocationContext *LC) { 290 291 // Are we never purging state values? 292 if (AMgr.options.AnalysisPurgeOpt == PurgeNone) 293 return false; 294 295 // Is this the beginning of a basic block? 296 if (Pred->getLocation().getAs<BlockEntrance>()) 297 return true; 298 299 // Is this on a non-expression? 300 if (!isa<Expr>(S.getStmt())) 301 return true; 302 303 // Run before processing a call. 304 if (CallEvent::isCallStmt(S.getStmt())) 305 return true; 306 307 // Is this an expression that is consumed by another expression? If so, 308 // postpone cleaning out the state. 309 ParentMap &PM = LC->getAnalysisDeclContext()->getParentMap(); 310 return !PM.isConsumedExpr(cast<Expr>(S.getStmt())); 311} 312 313void ExprEngine::removeDead(ExplodedNode *Pred, ExplodedNodeSet &Out, 314 const Stmt *ReferenceStmt, 315 const LocationContext *LC, 316 const Stmt *DiagnosticStmt, 317 ProgramPoint::Kind K) { 318 assert((K == ProgramPoint::PreStmtPurgeDeadSymbolsKind || 319 ReferenceStmt == 0 || isa<ReturnStmt>(ReferenceStmt)) 320 && "PostStmt is not generally supported by the SymbolReaper yet"); 321 assert(LC && "Must pass the current (or expiring) LocationContext"); 322 323 if (!DiagnosticStmt) { 324 DiagnosticStmt = ReferenceStmt; 325 assert(DiagnosticStmt && "Required for clearing a LocationContext"); 326 } 327 328 NumRemoveDeadBindings++; 329 ProgramStateRef CleanedState = Pred->getState(); 330 331 // LC is the location context being destroyed, but SymbolReaper wants a 332 // location context that is still live. (If this is the top-level stack 333 // frame, this will be null.) 334 if (!ReferenceStmt) { 335 assert(K == ProgramPoint::PostStmtPurgeDeadSymbolsKind && 336 "Use PostStmtPurgeDeadSymbolsKind for clearing a LocationContext"); 337 LC = LC->getParent(); 338 } 339 340 const StackFrameContext *SFC = LC ? LC->getCurrentStackFrame() : 0; 341 SymbolReaper SymReaper(SFC, ReferenceStmt, SymMgr, getStoreManager()); 342 343 getCheckerManager().runCheckersForLiveSymbols(CleanedState, SymReaper); 344 345 // Create a state in which dead bindings are removed from the environment 346 // and the store. TODO: The function should just return new env and store, 347 // not a new state. 348 CleanedState = StateMgr.removeDeadBindings(CleanedState, SFC, SymReaper); 349 350 // Process any special transfer function for dead symbols. 351 // A tag to track convenience transitions, which can be removed at cleanup. 352 static SimpleProgramPointTag cleanupTag("ExprEngine : Clean Node"); 353 if (!SymReaper.hasDeadSymbols()) { 354 // Generate a CleanedNode that has the environment and store cleaned 355 // up. Since no symbols are dead, we can optimize and not clean out 356 // the constraint manager. 357 StmtNodeBuilder Bldr(Pred, Out, *currBldrCtx); 358 Bldr.generateNode(DiagnosticStmt, Pred, CleanedState, &cleanupTag, K); 359 360 } else { 361 // Call checkers with the non-cleaned state so that they could query the 362 // values of the soon to be dead symbols. 363 ExplodedNodeSet CheckedSet; 364 getCheckerManager().runCheckersForDeadSymbols(CheckedSet, Pred, SymReaper, 365 DiagnosticStmt, *this, K); 366 367 // For each node in CheckedSet, generate CleanedNodes that have the 368 // environment, the store, and the constraints cleaned up but have the 369 // user-supplied states as the predecessors. 370 StmtNodeBuilder Bldr(CheckedSet, Out, *currBldrCtx); 371 for (ExplodedNodeSet::const_iterator 372 I = CheckedSet.begin(), E = CheckedSet.end(); I != E; ++I) { 373 ProgramStateRef CheckerState = (*I)->getState(); 374 375 // The constraint manager has not been cleaned up yet, so clean up now. 376 CheckerState = getConstraintManager().removeDeadBindings(CheckerState, 377 SymReaper); 378 379 assert(StateMgr.haveEqualEnvironments(CheckerState, Pred->getState()) && 380 "Checkers are not allowed to modify the Environment as a part of " 381 "checkDeadSymbols processing."); 382 assert(StateMgr.haveEqualStores(CheckerState, Pred->getState()) && 383 "Checkers are not allowed to modify the Store as a part of " 384 "checkDeadSymbols processing."); 385 386 // Create a state based on CleanedState with CheckerState GDM and 387 // generate a transition to that state. 388 ProgramStateRef CleanedCheckerSt = 389 StateMgr.getPersistentStateWithGDM(CleanedState, CheckerState); 390 Bldr.generateNode(DiagnosticStmt, *I, CleanedCheckerSt, &cleanupTag, K); 391 } 392 } 393} 394 395void ExprEngine::ProcessStmt(const CFGStmt S, 396 ExplodedNode *Pred) { 397 // Reclaim any unnecessary nodes in the ExplodedGraph. 398 G.reclaimRecentlyAllocatedNodes(); 399 400 const Stmt *currStmt = S.getStmt(); 401 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(), 402 currStmt->getLocStart(), 403 "Error evaluating statement"); 404 405 // Remove dead bindings and symbols. 406 ExplodedNodeSet CleanedStates; 407 if (shouldRemoveDeadBindings(AMgr, S, Pred, Pred->getLocationContext())){ 408 removeDead(Pred, CleanedStates, currStmt, Pred->getLocationContext()); 409 } else 410 CleanedStates.Add(Pred); 411 412 // Visit the statement. 413 ExplodedNodeSet Dst; 414 for (ExplodedNodeSet::iterator I = CleanedStates.begin(), 415 E = CleanedStates.end(); I != E; ++I) { 416 ExplodedNodeSet DstI; 417 // Visit the statement. 418 Visit(currStmt, *I, DstI); 419 Dst.insert(DstI); 420 } 421 422 // Enqueue the new nodes onto the work list. 423 Engine.enqueue(Dst, currBldrCtx->getBlock(), currStmtIdx); 424} 425 426void ExprEngine::ProcessInitializer(const CFGInitializer Init, 427 ExplodedNode *Pred) { 428 const CXXCtorInitializer *BMI = Init.getInitializer(); 429 430 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(), 431 BMI->getSourceLocation(), 432 "Error evaluating initializer"); 433 434 // We don't clean up dead bindings here. 435 const StackFrameContext *stackFrame = 436 cast<StackFrameContext>(Pred->getLocationContext()); 437 const CXXConstructorDecl *decl = 438 cast<CXXConstructorDecl>(stackFrame->getDecl()); 439 440 ProgramStateRef State = Pred->getState(); 441 SVal thisVal = State->getSVal(svalBuilder.getCXXThis(decl, stackFrame)); 442 443 ExplodedNodeSet Tmp(Pred); 444 SVal FieldLoc; 445 446 // Evaluate the initializer, if necessary 447 if (BMI->isAnyMemberInitializer()) { 448 // Constructors build the object directly in the field, 449 // but non-objects must be copied in from the initializer. 450 const Expr *Init = BMI->getInit()->IgnoreImplicit(); 451 if (!isa<CXXConstructExpr>(Init)) { 452 const ValueDecl *Field; 453 if (BMI->isIndirectMemberInitializer()) { 454 Field = BMI->getIndirectMember(); 455 FieldLoc = State->getLValue(BMI->getIndirectMember(), thisVal); 456 } else { 457 Field = BMI->getMember(); 458 FieldLoc = State->getLValue(BMI->getMember(), thisVal); 459 } 460 461 SVal InitVal; 462 if (BMI->getNumArrayIndices() > 0) { 463 // Handle arrays of trivial type. We can represent this with a 464 // primitive load/copy from the base array region. 465 const ArraySubscriptExpr *ASE; 466 while ((ASE = dyn_cast<ArraySubscriptExpr>(Init))) 467 Init = ASE->getBase()->IgnoreImplicit(); 468 469 SVal LValue = State->getSVal(Init, stackFrame); 470 if (Optional<Loc> LValueLoc = LValue.getAs<Loc>()) 471 InitVal = State->getSVal(*LValueLoc); 472 473 // If we fail to get the value for some reason, use a symbolic value. 474 if (InitVal.isUnknownOrUndef()) { 475 SValBuilder &SVB = getSValBuilder(); 476 InitVal = SVB.conjureSymbolVal(BMI->getInit(), stackFrame, 477 Field->getType(), 478 currBldrCtx->blockCount()); 479 } 480 } else { 481 InitVal = State->getSVal(BMI->getInit(), stackFrame); 482 } 483 484 assert(Tmp.size() == 1 && "have not generated any new nodes yet"); 485 assert(*Tmp.begin() == Pred && "have not generated any new nodes yet"); 486 Tmp.clear(); 487 488 PostInitializer PP(BMI, FieldLoc.getAsRegion(), stackFrame); 489 evalBind(Tmp, Init, Pred, FieldLoc, InitVal, /*isInit=*/true, &PP); 490 } 491 } else { 492 assert(BMI->isBaseInitializer() || BMI->isDelegatingInitializer()); 493 // We already did all the work when visiting the CXXConstructExpr. 494 } 495 496 // Construct PostInitializer nodes whether the state changed or not, 497 // so that the diagnostics don't get confused. 498 PostInitializer PP(BMI, FieldLoc.getAsRegion(), stackFrame); 499 ExplodedNodeSet Dst; 500 NodeBuilder Bldr(Tmp, Dst, *currBldrCtx); 501 for (ExplodedNodeSet::iterator I = Tmp.begin(), E = Tmp.end(); I != E; ++I) { 502 ExplodedNode *N = *I; 503 Bldr.generateNode(PP, N->getState(), N); 504 } 505 506 // Enqueue the new nodes onto the work list. 507 Engine.enqueue(Dst, currBldrCtx->getBlock(), currStmtIdx); 508} 509 510void ExprEngine::ProcessImplicitDtor(const CFGImplicitDtor D, 511 ExplodedNode *Pred) { 512 ExplodedNodeSet Dst; 513 switch (D.getKind()) { 514 case CFGElement::AutomaticObjectDtor: 515 ProcessAutomaticObjDtor(D.castAs<CFGAutomaticObjDtor>(), Pred, Dst); 516 break; 517 case CFGElement::BaseDtor: 518 ProcessBaseDtor(D.castAs<CFGBaseDtor>(), Pred, Dst); 519 break; 520 case CFGElement::MemberDtor: 521 ProcessMemberDtor(D.castAs<CFGMemberDtor>(), Pred, Dst); 522 break; 523 case CFGElement::TemporaryDtor: 524 ProcessTemporaryDtor(D.castAs<CFGTemporaryDtor>(), Pred, Dst); 525 break; 526 default: 527 llvm_unreachable("Unexpected dtor kind."); 528 } 529 530 // Enqueue the new nodes onto the work list. 531 Engine.enqueue(Dst, currBldrCtx->getBlock(), currStmtIdx); 532} 533 534void ExprEngine::ProcessAutomaticObjDtor(const CFGAutomaticObjDtor Dtor, 535 ExplodedNode *Pred, 536 ExplodedNodeSet &Dst) { 537 const VarDecl *varDecl = Dtor.getVarDecl(); 538 QualType varType = varDecl->getType(); 539 540 ProgramStateRef state = Pred->getState(); 541 SVal dest = state->getLValue(varDecl, Pred->getLocationContext()); 542 const MemRegion *Region = dest.castAs<loc::MemRegionVal>().getRegion(); 543 544 if (const ReferenceType *refType = varType->getAs<ReferenceType>()) { 545 varType = refType->getPointeeType(); 546 Region = state->getSVal(Region).getAsRegion(); 547 } 548 549 VisitCXXDestructor(varType, Region, Dtor.getTriggerStmt(), /*IsBase=*/ false, 550 Pred, Dst); 551} 552 553void ExprEngine::ProcessBaseDtor(const CFGBaseDtor D, 554 ExplodedNode *Pred, ExplodedNodeSet &Dst) { 555 const LocationContext *LCtx = Pred->getLocationContext(); 556 ProgramStateRef State = Pred->getState(); 557 558 const CXXDestructorDecl *CurDtor = cast<CXXDestructorDecl>(LCtx->getDecl()); 559 Loc ThisPtr = getSValBuilder().getCXXThis(CurDtor, 560 LCtx->getCurrentStackFrame()); 561 SVal ThisVal = Pred->getState()->getSVal(ThisPtr); 562 563 // Create the base object region. 564 const CXXBaseSpecifier *Base = D.getBaseSpecifier(); 565 QualType BaseTy = Base->getType(); 566 SVal BaseVal = getStoreManager().evalDerivedToBase(ThisVal, BaseTy, 567 Base->isVirtual()); 568 569 VisitCXXDestructor(BaseTy, BaseVal.castAs<loc::MemRegionVal>().getRegion(), 570 CurDtor->getBody(), /*IsBase=*/ true, Pred, Dst); 571} 572 573void ExprEngine::ProcessMemberDtor(const CFGMemberDtor D, 574 ExplodedNode *Pred, ExplodedNodeSet &Dst) { 575 const FieldDecl *Member = D.getFieldDecl(); 576 ProgramStateRef State = Pred->getState(); 577 const LocationContext *LCtx = Pred->getLocationContext(); 578 579 const CXXDestructorDecl *CurDtor = cast<CXXDestructorDecl>(LCtx->getDecl()); 580 Loc ThisVal = getSValBuilder().getCXXThis(CurDtor, 581 LCtx->getCurrentStackFrame()); 582 SVal FieldVal = 583 State->getLValue(Member, State->getSVal(ThisVal).castAs<Loc>()); 584 585 VisitCXXDestructor(Member->getType(), 586 FieldVal.castAs<loc::MemRegionVal>().getRegion(), 587 CurDtor->getBody(), /*IsBase=*/false, Pred, Dst); 588} 589 590void ExprEngine::ProcessTemporaryDtor(const CFGTemporaryDtor D, 591 ExplodedNode *Pred, 592 ExplodedNodeSet &Dst) {} 593 594void ExprEngine::Visit(const Stmt *S, ExplodedNode *Pred, 595 ExplodedNodeSet &DstTop) { 596 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(), 597 S->getLocStart(), 598 "Error evaluating statement"); 599 ExplodedNodeSet Dst; 600 StmtNodeBuilder Bldr(Pred, DstTop, *currBldrCtx); 601 602 assert(!isa<Expr>(S) || S == cast<Expr>(S)->IgnoreParens()); 603 604 switch (S->getStmtClass()) { 605 // C++ and ARC stuff we don't support yet. 606 case Expr::ObjCIndirectCopyRestoreExprClass: 607 case Stmt::CXXDefaultInitExprClass: 608 case Stmt::CXXDependentScopeMemberExprClass: 609 case Stmt::CXXPseudoDestructorExprClass: 610 case Stmt::CXXTryStmtClass: 611 case Stmt::CXXTypeidExprClass: 612 case Stmt::CXXUuidofExprClass: 613 case Stmt::MSPropertyRefExprClass: 614 case Stmt::CXXUnresolvedConstructExprClass: 615 case Stmt::DependentScopeDeclRefExprClass: 616 case Stmt::UnaryTypeTraitExprClass: 617 case Stmt::BinaryTypeTraitExprClass: 618 case Stmt::TypeTraitExprClass: 619 case Stmt::ArrayTypeTraitExprClass: 620 case Stmt::ExpressionTraitExprClass: 621 case Stmt::UnresolvedLookupExprClass: 622 case Stmt::UnresolvedMemberExprClass: 623 case Stmt::CXXNoexceptExprClass: 624 case Stmt::PackExpansionExprClass: 625 case Stmt::SubstNonTypeTemplateParmPackExprClass: 626 case Stmt::FunctionParmPackExprClass: 627 case Stmt::SEHTryStmtClass: 628 case Stmt::SEHExceptStmtClass: 629 case Stmt::LambdaExprClass: 630 case Stmt::SEHFinallyStmtClass: { 631 const ExplodedNode *node = Bldr.generateSink(S, Pred, Pred->getState()); 632 Engine.addAbortedBlock(node, currBldrCtx->getBlock()); 633 break; 634 } 635 636 case Stmt::ParenExprClass: 637 llvm_unreachable("ParenExprs already handled."); 638 case Stmt::GenericSelectionExprClass: 639 llvm_unreachable("GenericSelectionExprs already handled."); 640 // Cases that should never be evaluated simply because they shouldn't 641 // appear in the CFG. 642 case Stmt::BreakStmtClass: 643 case Stmt::CaseStmtClass: 644 case Stmt::CompoundStmtClass: 645 case Stmt::ContinueStmtClass: 646 case Stmt::CXXForRangeStmtClass: 647 case Stmt::DefaultStmtClass: 648 case Stmt::DoStmtClass: 649 case Stmt::ForStmtClass: 650 case Stmt::GotoStmtClass: 651 case Stmt::IfStmtClass: 652 case Stmt::IndirectGotoStmtClass: 653 case Stmt::LabelStmtClass: 654 case Stmt::AttributedStmtClass: 655 case Stmt::NoStmtClass: 656 case Stmt::NullStmtClass: 657 case Stmt::SwitchStmtClass: 658 case Stmt::WhileStmtClass: 659 case Expr::MSDependentExistsStmtClass: 660 case Stmt::CapturedStmtClass: 661 llvm_unreachable("Stmt should not be in analyzer evaluation loop"); 662 663 case Stmt::ObjCSubscriptRefExprClass: 664 case Stmt::ObjCPropertyRefExprClass: 665 llvm_unreachable("These are handled by PseudoObjectExpr"); 666 667 case Stmt::GNUNullExprClass: { 668 // GNU __null is a pointer-width integer, not an actual pointer. 669 ProgramStateRef state = Pred->getState(); 670 state = state->BindExpr(S, Pred->getLocationContext(), 671 svalBuilder.makeIntValWithPtrWidth(0, false)); 672 Bldr.generateNode(S, Pred, state); 673 break; 674 } 675 676 case Stmt::ObjCAtSynchronizedStmtClass: 677 Bldr.takeNodes(Pred); 678 VisitObjCAtSynchronizedStmt(cast<ObjCAtSynchronizedStmt>(S), Pred, Dst); 679 Bldr.addNodes(Dst); 680 break; 681 682 case Stmt::ExprWithCleanupsClass: 683 // Handled due to fully linearised CFG. 684 break; 685 686 // Cases not handled yet; but will handle some day. 687 case Stmt::DesignatedInitExprClass: 688 case Stmt::ExtVectorElementExprClass: 689 case Stmt::ImaginaryLiteralClass: 690 case Stmt::ObjCAtCatchStmtClass: 691 case Stmt::ObjCAtFinallyStmtClass: 692 case Stmt::ObjCAtTryStmtClass: 693 case Stmt::ObjCAutoreleasePoolStmtClass: 694 case Stmt::ObjCEncodeExprClass: 695 case Stmt::ObjCIsaExprClass: 696 case Stmt::ObjCProtocolExprClass: 697 case Stmt::ObjCSelectorExprClass: 698 case Stmt::ParenListExprClass: 699 case Stmt::PredefinedExprClass: 700 case Stmt::ShuffleVectorExprClass: 701 case Stmt::VAArgExprClass: 702 case Stmt::CUDAKernelCallExprClass: 703 case Stmt::OpaqueValueExprClass: 704 case Stmt::AsTypeExprClass: 705 case Stmt::AtomicExprClass: 706 // Fall through. 707 708 // Cases we intentionally don't evaluate, since they don't need 709 // to be explicitly evaluated. 710 case Stmt::AddrLabelExprClass: 711 case Stmt::IntegerLiteralClass: 712 case Stmt::CharacterLiteralClass: 713 case Stmt::ImplicitValueInitExprClass: 714 case Stmt::CXXScalarValueInitExprClass: 715 case Stmt::CXXBoolLiteralExprClass: 716 case Stmt::ObjCBoolLiteralExprClass: 717 case Stmt::FloatingLiteralClass: 718 case Stmt::SizeOfPackExprClass: 719 case Stmt::StringLiteralClass: 720 case Stmt::ObjCStringLiteralClass: 721 case Stmt::CXXBindTemporaryExprClass: 722 case Stmt::SubstNonTypeTemplateParmExprClass: 723 case Stmt::CXXNullPtrLiteralExprClass: { 724 Bldr.takeNodes(Pred); 725 ExplodedNodeSet preVisit; 726 getCheckerManager().runCheckersForPreStmt(preVisit, Pred, S, *this); 727 getCheckerManager().runCheckersForPostStmt(Dst, preVisit, S, *this); 728 Bldr.addNodes(Dst); 729 break; 730 } 731 732 case Stmt::CXXDefaultArgExprClass: { 733 Bldr.takeNodes(Pred); 734 ExplodedNodeSet PreVisit; 735 getCheckerManager().runCheckersForPreStmt(PreVisit, Pred, S, *this); 736 737 ExplodedNodeSet Tmp; 738 StmtNodeBuilder Bldr2(PreVisit, Tmp, *currBldrCtx); 739 740 const LocationContext *LCtx = Pred->getLocationContext(); 741 const CXXDefaultArgExpr *DefaultE = cast<CXXDefaultArgExpr>(S); 742 const Expr *ArgE = DefaultE->getExpr(); 743 744 // Avoid creating and destroying a lot of APSInts. 745 SVal V; 746 llvm::APSInt Result; 747 748 for (ExplodedNodeSet::iterator I = PreVisit.begin(), E = PreVisit.end(); 749 I != E; ++I) { 750 ProgramStateRef State = (*I)->getState(); 751 752 if (ArgE->EvaluateAsInt(Result, getContext())) 753 V = svalBuilder.makeIntVal(Result); 754 else 755 V = State->getSVal(ArgE, LCtx); 756 757 State = State->BindExpr(DefaultE, LCtx, V); 758 if (DefaultE->isGLValue()) 759 State = createTemporaryRegionIfNeeded(State, LCtx, DefaultE, 760 DefaultE); 761 Bldr2.generateNode(S, *I, State); 762 } 763 764 getCheckerManager().runCheckersForPostStmt(Dst, Tmp, S, *this); 765 Bldr.addNodes(Dst); 766 break; 767 } 768 769 case Expr::ObjCArrayLiteralClass: 770 case Expr::ObjCDictionaryLiteralClass: 771 // FIXME: explicitly model with a region and the actual contents 772 // of the container. For now, conjure a symbol. 773 case Expr::ObjCBoxedExprClass: { 774 Bldr.takeNodes(Pred); 775 776 ExplodedNodeSet preVisit; 777 getCheckerManager().runCheckersForPreStmt(preVisit, Pred, S, *this); 778 779 ExplodedNodeSet Tmp; 780 StmtNodeBuilder Bldr2(preVisit, Tmp, *currBldrCtx); 781 782 const Expr *Ex = cast<Expr>(S); 783 QualType resultType = Ex->getType(); 784 785 for (ExplodedNodeSet::iterator it = preVisit.begin(), et = preVisit.end(); 786 it != et; ++it) { 787 ExplodedNode *N = *it; 788 const LocationContext *LCtx = N->getLocationContext(); 789 SVal result = svalBuilder.conjureSymbolVal(0, Ex, LCtx, resultType, 790 currBldrCtx->blockCount()); 791 ProgramStateRef state = N->getState()->BindExpr(Ex, LCtx, result); 792 Bldr2.generateNode(S, N, state); 793 } 794 795 getCheckerManager().runCheckersForPostStmt(Dst, Tmp, S, *this); 796 Bldr.addNodes(Dst); 797 break; 798 } 799 800 case Stmt::ArraySubscriptExprClass: 801 Bldr.takeNodes(Pred); 802 VisitLvalArraySubscriptExpr(cast<ArraySubscriptExpr>(S), Pred, Dst); 803 Bldr.addNodes(Dst); 804 break; 805 806 case Stmt::GCCAsmStmtClass: 807 Bldr.takeNodes(Pred); 808 VisitGCCAsmStmt(cast<GCCAsmStmt>(S), Pred, Dst); 809 Bldr.addNodes(Dst); 810 break; 811 812 case Stmt::MSAsmStmtClass: 813 Bldr.takeNodes(Pred); 814 VisitMSAsmStmt(cast<MSAsmStmt>(S), Pred, Dst); 815 Bldr.addNodes(Dst); 816 break; 817 818 case Stmt::BlockExprClass: 819 Bldr.takeNodes(Pred); 820 VisitBlockExpr(cast<BlockExpr>(S), Pred, Dst); 821 Bldr.addNodes(Dst); 822 break; 823 824 case Stmt::BinaryOperatorClass: { 825 const BinaryOperator* B = cast<BinaryOperator>(S); 826 if (B->isLogicalOp()) { 827 Bldr.takeNodes(Pred); 828 VisitLogicalExpr(B, Pred, Dst); 829 Bldr.addNodes(Dst); 830 break; 831 } 832 else if (B->getOpcode() == BO_Comma) { 833 ProgramStateRef state = Pred->getState(); 834 Bldr.generateNode(B, Pred, 835 state->BindExpr(B, Pred->getLocationContext(), 836 state->getSVal(B->getRHS(), 837 Pred->getLocationContext()))); 838 break; 839 } 840 841 Bldr.takeNodes(Pred); 842 843 if (AMgr.options.eagerlyAssumeBinOpBifurcation && 844 (B->isRelationalOp() || B->isEqualityOp())) { 845 ExplodedNodeSet Tmp; 846 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Tmp); 847 evalEagerlyAssumeBinOpBifurcation(Dst, Tmp, cast<Expr>(S)); 848 } 849 else 850 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Dst); 851 852 Bldr.addNodes(Dst); 853 break; 854 } 855 856 case Stmt::CXXOperatorCallExprClass: { 857 const CXXOperatorCallExpr *OCE = cast<CXXOperatorCallExpr>(S); 858 859 // For instance method operators, make sure the 'this' argument has a 860 // valid region. 861 const Decl *Callee = OCE->getCalleeDecl(); 862 if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Callee)) { 863 if (MD->isInstance()) { 864 ProgramStateRef State = Pred->getState(); 865 const LocationContext *LCtx = Pred->getLocationContext(); 866 ProgramStateRef NewState = 867 createTemporaryRegionIfNeeded(State, LCtx, OCE->getArg(0)); 868 if (NewState != State) { 869 Pred = Bldr.generateNode(OCE, Pred, NewState, /*Tag=*/0, 870 ProgramPoint::PreStmtKind); 871 // Did we cache out? 872 if (!Pred) 873 break; 874 } 875 } 876 } 877 // FALLTHROUGH 878 } 879 case Stmt::CallExprClass: 880 case Stmt::CXXMemberCallExprClass: 881 case Stmt::UserDefinedLiteralClass: { 882 Bldr.takeNodes(Pred); 883 VisitCallExpr(cast<CallExpr>(S), Pred, Dst); 884 Bldr.addNodes(Dst); 885 break; 886 } 887 888 case Stmt::CXXCatchStmtClass: { 889 Bldr.takeNodes(Pred); 890 VisitCXXCatchStmt(cast<CXXCatchStmt>(S), Pred, Dst); 891 Bldr.addNodes(Dst); 892 break; 893 } 894 895 case Stmt::CXXTemporaryObjectExprClass: 896 case Stmt::CXXConstructExprClass: { 897 Bldr.takeNodes(Pred); 898 VisitCXXConstructExpr(cast<CXXConstructExpr>(S), Pred, Dst); 899 Bldr.addNodes(Dst); 900 break; 901 } 902 903 case Stmt::CXXNewExprClass: { 904 Bldr.takeNodes(Pred); 905 ExplodedNodeSet PostVisit; 906 VisitCXXNewExpr(cast<CXXNewExpr>(S), Pred, PostVisit); 907 getCheckerManager().runCheckersForPostStmt(Dst, PostVisit, S, *this); 908 Bldr.addNodes(Dst); 909 break; 910 } 911 912 case Stmt::CXXDeleteExprClass: { 913 Bldr.takeNodes(Pred); 914 ExplodedNodeSet PreVisit; 915 const CXXDeleteExpr *CDE = cast<CXXDeleteExpr>(S); 916 getCheckerManager().runCheckersForPreStmt(PreVisit, Pred, S, *this); 917 918 for (ExplodedNodeSet::iterator i = PreVisit.begin(), 919 e = PreVisit.end(); i != e ; ++i) 920 VisitCXXDeleteExpr(CDE, *i, Dst); 921 922 Bldr.addNodes(Dst); 923 break; 924 } 925 // FIXME: ChooseExpr is really a constant. We need to fix 926 // the CFG do not model them as explicit control-flow. 927 928 case Stmt::ChooseExprClass: { // __builtin_choose_expr 929 Bldr.takeNodes(Pred); 930 const ChooseExpr *C = cast<ChooseExpr>(S); 931 VisitGuardedExpr(C, C->getLHS(), C->getRHS(), Pred, Dst); 932 Bldr.addNodes(Dst); 933 break; 934 } 935 936 case Stmt::CompoundAssignOperatorClass: 937 Bldr.takeNodes(Pred); 938 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Dst); 939 Bldr.addNodes(Dst); 940 break; 941 942 case Stmt::CompoundLiteralExprClass: 943 Bldr.takeNodes(Pred); 944 VisitCompoundLiteralExpr(cast<CompoundLiteralExpr>(S), Pred, Dst); 945 Bldr.addNodes(Dst); 946 break; 947 948 case Stmt::BinaryConditionalOperatorClass: 949 case Stmt::ConditionalOperatorClass: { // '?' operator 950 Bldr.takeNodes(Pred); 951 const AbstractConditionalOperator *C 952 = cast<AbstractConditionalOperator>(S); 953 VisitGuardedExpr(C, C->getTrueExpr(), C->getFalseExpr(), Pred, Dst); 954 Bldr.addNodes(Dst); 955 break; 956 } 957 958 case Stmt::CXXThisExprClass: 959 Bldr.takeNodes(Pred); 960 VisitCXXThisExpr(cast<CXXThisExpr>(S), Pred, Dst); 961 Bldr.addNodes(Dst); 962 break; 963 964 case Stmt::DeclRefExprClass: { 965 Bldr.takeNodes(Pred); 966 const DeclRefExpr *DE = cast<DeclRefExpr>(S); 967 VisitCommonDeclRefExpr(DE, DE->getDecl(), Pred, Dst); 968 Bldr.addNodes(Dst); 969 break; 970 } 971 972 case Stmt::DeclStmtClass: 973 Bldr.takeNodes(Pred); 974 VisitDeclStmt(cast<DeclStmt>(S), Pred, Dst); 975 Bldr.addNodes(Dst); 976 break; 977 978 case Stmt::ImplicitCastExprClass: 979 case Stmt::CStyleCastExprClass: 980 case Stmt::CXXStaticCastExprClass: 981 case Stmt::CXXDynamicCastExprClass: 982 case Stmt::CXXReinterpretCastExprClass: 983 case Stmt::CXXConstCastExprClass: 984 case Stmt::CXXFunctionalCastExprClass: 985 case Stmt::ObjCBridgedCastExprClass: { 986 Bldr.takeNodes(Pred); 987 const CastExpr *C = cast<CastExpr>(S); 988 // Handle the previsit checks. 989 ExplodedNodeSet dstPrevisit; 990 getCheckerManager().runCheckersForPreStmt(dstPrevisit, Pred, C, *this); 991 992 // Handle the expression itself. 993 ExplodedNodeSet dstExpr; 994 for (ExplodedNodeSet::iterator i = dstPrevisit.begin(), 995 e = dstPrevisit.end(); i != e ; ++i) { 996 VisitCast(C, C->getSubExpr(), *i, dstExpr); 997 } 998 999 // Handle the postvisit checks. 1000 getCheckerManager().runCheckersForPostStmt(Dst, dstExpr, C, *this); 1001 Bldr.addNodes(Dst); 1002 break; 1003 } 1004 1005 case Expr::MaterializeTemporaryExprClass: { 1006 Bldr.takeNodes(Pred); 1007 const MaterializeTemporaryExpr *MTE = cast<MaterializeTemporaryExpr>(S); 1008 CreateCXXTemporaryObject(MTE, Pred, Dst); 1009 Bldr.addNodes(Dst); 1010 break; 1011 } 1012 1013 case Stmt::InitListExprClass: 1014 Bldr.takeNodes(Pred); 1015 VisitInitListExpr(cast<InitListExpr>(S), Pred, Dst); 1016 Bldr.addNodes(Dst); 1017 break; 1018 1019 case Stmt::MemberExprClass: 1020 Bldr.takeNodes(Pred); 1021 VisitMemberExpr(cast<MemberExpr>(S), Pred, Dst); 1022 Bldr.addNodes(Dst); 1023 break; 1024 1025 case Stmt::ObjCIvarRefExprClass: 1026 Bldr.takeNodes(Pred); 1027 VisitLvalObjCIvarRefExpr(cast<ObjCIvarRefExpr>(S), Pred, Dst); 1028 Bldr.addNodes(Dst); 1029 break; 1030 1031 case Stmt::ObjCForCollectionStmtClass: 1032 Bldr.takeNodes(Pred); 1033 VisitObjCForCollectionStmt(cast<ObjCForCollectionStmt>(S), Pred, Dst); 1034 Bldr.addNodes(Dst); 1035 break; 1036 1037 case Stmt::ObjCMessageExprClass: 1038 Bldr.takeNodes(Pred); 1039 VisitObjCMessage(cast<ObjCMessageExpr>(S), Pred, Dst); 1040 Bldr.addNodes(Dst); 1041 break; 1042 1043 case Stmt::ObjCAtThrowStmtClass: 1044 case Stmt::CXXThrowExprClass: 1045 // FIXME: This is not complete. We basically treat @throw as 1046 // an abort. 1047 Bldr.generateSink(S, Pred, Pred->getState()); 1048 break; 1049 1050 case Stmt::ReturnStmtClass: 1051 Bldr.takeNodes(Pred); 1052 VisitReturnStmt(cast<ReturnStmt>(S), Pred, Dst); 1053 Bldr.addNodes(Dst); 1054 break; 1055 1056 case Stmt::OffsetOfExprClass: 1057 Bldr.takeNodes(Pred); 1058 VisitOffsetOfExpr(cast<OffsetOfExpr>(S), Pred, Dst); 1059 Bldr.addNodes(Dst); 1060 break; 1061 1062 case Stmt::UnaryExprOrTypeTraitExprClass: 1063 Bldr.takeNodes(Pred); 1064 VisitUnaryExprOrTypeTraitExpr(cast<UnaryExprOrTypeTraitExpr>(S), 1065 Pred, Dst); 1066 Bldr.addNodes(Dst); 1067 break; 1068 1069 case Stmt::StmtExprClass: { 1070 const StmtExpr *SE = cast<StmtExpr>(S); 1071 1072 if (SE->getSubStmt()->body_empty()) { 1073 // Empty statement expression. 1074 assert(SE->getType() == getContext().VoidTy 1075 && "Empty statement expression must have void type."); 1076 break; 1077 } 1078 1079 if (Expr *LastExpr = dyn_cast<Expr>(*SE->getSubStmt()->body_rbegin())) { 1080 ProgramStateRef state = Pred->getState(); 1081 Bldr.generateNode(SE, Pred, 1082 state->BindExpr(SE, Pred->getLocationContext(), 1083 state->getSVal(LastExpr, 1084 Pred->getLocationContext()))); 1085 } 1086 break; 1087 } 1088 1089 case Stmt::UnaryOperatorClass: { 1090 Bldr.takeNodes(Pred); 1091 const UnaryOperator *U = cast<UnaryOperator>(S); 1092 if (AMgr.options.eagerlyAssumeBinOpBifurcation && (U->getOpcode() == UO_LNot)) { 1093 ExplodedNodeSet Tmp; 1094 VisitUnaryOperator(U, Pred, Tmp); 1095 evalEagerlyAssumeBinOpBifurcation(Dst, Tmp, U); 1096 } 1097 else 1098 VisitUnaryOperator(U, Pred, Dst); 1099 Bldr.addNodes(Dst); 1100 break; 1101 } 1102 1103 case Stmt::PseudoObjectExprClass: { 1104 Bldr.takeNodes(Pred); 1105 ProgramStateRef state = Pred->getState(); 1106 const PseudoObjectExpr *PE = cast<PseudoObjectExpr>(S); 1107 if (const Expr *Result = PE->getResultExpr()) { 1108 SVal V = state->getSVal(Result, Pred->getLocationContext()); 1109 Bldr.generateNode(S, Pred, 1110 state->BindExpr(S, Pred->getLocationContext(), V)); 1111 } 1112 else 1113 Bldr.generateNode(S, Pred, 1114 state->BindExpr(S, Pred->getLocationContext(), 1115 UnknownVal())); 1116 1117 Bldr.addNodes(Dst); 1118 break; 1119 } 1120 } 1121} 1122 1123bool ExprEngine::replayWithoutInlining(ExplodedNode *N, 1124 const LocationContext *CalleeLC) { 1125 const StackFrameContext *CalleeSF = CalleeLC->getCurrentStackFrame(); 1126 const StackFrameContext *CallerSF = CalleeSF->getParent()->getCurrentStackFrame(); 1127 assert(CalleeSF && CallerSF); 1128 ExplodedNode *BeforeProcessingCall = 0; 1129 const Stmt *CE = CalleeSF->getCallSite(); 1130 1131 // Find the first node before we started processing the call expression. 1132 while (N) { 1133 ProgramPoint L = N->getLocation(); 1134 BeforeProcessingCall = N; 1135 N = N->pred_empty() ? NULL : *(N->pred_begin()); 1136 1137 // Skip the nodes corresponding to the inlined code. 1138 if (L.getLocationContext()->getCurrentStackFrame() != CallerSF) 1139 continue; 1140 // We reached the caller. Find the node right before we started 1141 // processing the call. 1142 if (L.isPurgeKind()) 1143 continue; 1144 if (L.getAs<PreImplicitCall>()) 1145 continue; 1146 if (L.getAs<CallEnter>()) 1147 continue; 1148 if (Optional<StmtPoint> SP = L.getAs<StmtPoint>()) 1149 if (SP->getStmt() == CE) 1150 continue; 1151 break; 1152 } 1153 1154 if (!BeforeProcessingCall) 1155 return false; 1156 1157 // TODO: Clean up the unneeded nodes. 1158 1159 // Build an Epsilon node from which we will restart the analyzes. 1160 // Note that CE is permitted to be NULL! 1161 ProgramPoint NewNodeLoc = 1162 EpsilonPoint(BeforeProcessingCall->getLocationContext(), CE); 1163 // Add the special flag to GDM to signal retrying with no inlining. 1164 // Note, changing the state ensures that we are not going to cache out. 1165 ProgramStateRef NewNodeState = BeforeProcessingCall->getState(); 1166 NewNodeState = 1167 NewNodeState->set<ReplayWithoutInlining>(const_cast<Stmt *>(CE)); 1168 1169 // Make the new node a successor of BeforeProcessingCall. 1170 bool IsNew = false; 1171 ExplodedNode *NewNode = G.getNode(NewNodeLoc, NewNodeState, false, &IsNew); 1172 // We cached out at this point. Caching out is common due to us backtracking 1173 // from the inlined function, which might spawn several paths. 1174 if (!IsNew) 1175 return true; 1176 1177 NewNode->addPredecessor(BeforeProcessingCall, G); 1178 1179 // Add the new node to the work list. 1180 Engine.enqueueStmtNode(NewNode, CalleeSF->getCallSiteBlock(), 1181 CalleeSF->getIndex()); 1182 NumTimesRetriedWithoutInlining++; 1183 return true; 1184} 1185 1186/// Block entrance. (Update counters). 1187void ExprEngine::processCFGBlockEntrance(const BlockEdge &L, 1188 NodeBuilderWithSinks &nodeBuilder, 1189 ExplodedNode *Pred) { 1190 1191 // FIXME: Refactor this into a checker. 1192 if (nodeBuilder.getContext().blockCount() >= AMgr.options.maxBlockVisitOnPath) { 1193 static SimpleProgramPointTag tag("ExprEngine : Block count exceeded"); 1194 const ExplodedNode *Sink = 1195 nodeBuilder.generateSink(Pred->getState(), Pred, &tag); 1196 1197 // Check if we stopped at the top level function or not. 1198 // Root node should have the location context of the top most function. 1199 const LocationContext *CalleeLC = Pred->getLocation().getLocationContext(); 1200 const LocationContext *CalleeSF = CalleeLC->getCurrentStackFrame(); 1201 const LocationContext *RootLC = 1202 (*G.roots_begin())->getLocation().getLocationContext(); 1203 if (RootLC->getCurrentStackFrame() != CalleeSF) { 1204 Engine.FunctionSummaries->markReachedMaxBlockCount(CalleeSF->getDecl()); 1205 1206 // Re-run the call evaluation without inlining it, by storing the 1207 // no-inlining policy in the state and enqueuing the new work item on 1208 // the list. Replay should almost never fail. Use the stats to catch it 1209 // if it does. 1210 if ((!AMgr.options.NoRetryExhausted && 1211 replayWithoutInlining(Pred, CalleeLC))) 1212 return; 1213 NumMaxBlockCountReachedInInlined++; 1214 } else 1215 NumMaxBlockCountReached++; 1216 1217 // Make sink nodes as exhausted(for stats) only if retry failed. 1218 Engine.blocksExhausted.push_back(std::make_pair(L, Sink)); 1219 } 1220} 1221 1222//===----------------------------------------------------------------------===// 1223// Branch processing. 1224//===----------------------------------------------------------------------===// 1225 1226/// RecoverCastedSymbol - A helper function for ProcessBranch that is used 1227/// to try to recover some path-sensitivity for casts of symbolic 1228/// integers that promote their values (which are currently not tracked well). 1229/// This function returns the SVal bound to Condition->IgnoreCasts if all the 1230// cast(s) did was sign-extend the original value. 1231static SVal RecoverCastedSymbol(ProgramStateManager& StateMgr, 1232 ProgramStateRef state, 1233 const Stmt *Condition, 1234 const LocationContext *LCtx, 1235 ASTContext &Ctx) { 1236 1237 const Expr *Ex = dyn_cast<Expr>(Condition); 1238 if (!Ex) 1239 return UnknownVal(); 1240 1241 uint64_t bits = 0; 1242 bool bitsInit = false; 1243 1244 while (const CastExpr *CE = dyn_cast<CastExpr>(Ex)) { 1245 QualType T = CE->getType(); 1246 1247 if (!T->isIntegralOrEnumerationType()) 1248 return UnknownVal(); 1249 1250 uint64_t newBits = Ctx.getTypeSize(T); 1251 if (!bitsInit || newBits < bits) { 1252 bitsInit = true; 1253 bits = newBits; 1254 } 1255 1256 Ex = CE->getSubExpr(); 1257 } 1258 1259 // We reached a non-cast. Is it a symbolic value? 1260 QualType T = Ex->getType(); 1261 1262 if (!bitsInit || !T->isIntegralOrEnumerationType() || 1263 Ctx.getTypeSize(T) > bits) 1264 return UnknownVal(); 1265 1266 return state->getSVal(Ex, LCtx); 1267} 1268 1269static const Stmt *ResolveCondition(const Stmt *Condition, 1270 const CFGBlock *B) { 1271 if (const Expr *Ex = dyn_cast<Expr>(Condition)) 1272 Condition = Ex->IgnoreParens(); 1273 1274 const BinaryOperator *BO = dyn_cast<BinaryOperator>(Condition); 1275 if (!BO || !BO->isLogicalOp()) 1276 return Condition; 1277 1278 // For logical operations, we still have the case where some branches 1279 // use the traditional "merge" approach and others sink the branch 1280 // directly into the basic blocks representing the logical operation. 1281 // We need to distinguish between those two cases here. 1282 1283 // The invariants are still shifting, but it is possible that the 1284 // last element in a CFGBlock is not a CFGStmt. Look for the last 1285 // CFGStmt as the value of the condition. 1286 CFGBlock::const_reverse_iterator I = B->rbegin(), E = B->rend(); 1287 for (; I != E; ++I) { 1288 CFGElement Elem = *I; 1289 Optional<CFGStmt> CS = Elem.getAs<CFGStmt>(); 1290 if (!CS) 1291 continue; 1292 if (CS->getStmt() != Condition) 1293 break; 1294 return Condition; 1295 } 1296 1297 assert(I != E); 1298 1299 while (Condition) { 1300 BO = dyn_cast<BinaryOperator>(Condition); 1301 if (!BO || !BO->isLogicalOp()) 1302 return Condition; 1303 Condition = BO->getRHS()->IgnoreParens(); 1304 } 1305 llvm_unreachable("could not resolve condition"); 1306} 1307 1308void ExprEngine::processBranch(const Stmt *Condition, const Stmt *Term, 1309 NodeBuilderContext& BldCtx, 1310 ExplodedNode *Pred, 1311 ExplodedNodeSet &Dst, 1312 const CFGBlock *DstT, 1313 const CFGBlock *DstF) { 1314 currBldrCtx = &BldCtx; 1315 1316 // Check for NULL conditions; e.g. "for(;;)" 1317 if (!Condition) { 1318 BranchNodeBuilder NullCondBldr(Pred, Dst, BldCtx, DstT, DstF); 1319 NullCondBldr.markInfeasible(false); 1320 NullCondBldr.generateNode(Pred->getState(), true, Pred); 1321 return; 1322 } 1323 1324 1325 // Resolve the condition in the precense of nested '||' and '&&'. 1326 if (const Expr *Ex = dyn_cast<Expr>(Condition)) 1327 Condition = Ex->IgnoreParens(); 1328 1329 Condition = ResolveCondition(Condition, BldCtx.getBlock()); 1330 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(), 1331 Condition->getLocStart(), 1332 "Error evaluating branch"); 1333 1334 ExplodedNodeSet CheckersOutSet; 1335 getCheckerManager().runCheckersForBranchCondition(Condition, CheckersOutSet, 1336 Pred, *this); 1337 // We generated only sinks. 1338 if (CheckersOutSet.empty()) 1339 return; 1340 1341 BranchNodeBuilder builder(CheckersOutSet, Dst, BldCtx, DstT, DstF); 1342 for (NodeBuilder::iterator I = CheckersOutSet.begin(), 1343 E = CheckersOutSet.end(); E != I; ++I) { 1344 ExplodedNode *PredI = *I; 1345 1346 if (PredI->isSink()) 1347 continue; 1348 1349 ProgramStateRef PrevState = PredI->getState(); 1350 SVal X = PrevState->getSVal(Condition, PredI->getLocationContext()); 1351 1352 if (X.isUnknownOrUndef()) { 1353 // Give it a chance to recover from unknown. 1354 if (const Expr *Ex = dyn_cast<Expr>(Condition)) { 1355 if (Ex->getType()->isIntegralOrEnumerationType()) { 1356 // Try to recover some path-sensitivity. Right now casts of symbolic 1357 // integers that promote their values are currently not tracked well. 1358 // If 'Condition' is such an expression, try and recover the 1359 // underlying value and use that instead. 1360 SVal recovered = RecoverCastedSymbol(getStateManager(), 1361 PrevState, Condition, 1362 PredI->getLocationContext(), 1363 getContext()); 1364 1365 if (!recovered.isUnknown()) { 1366 X = recovered; 1367 } 1368 } 1369 } 1370 } 1371 1372 // If the condition is still unknown, give up. 1373 if (X.isUnknownOrUndef()) { 1374 builder.generateNode(PrevState, true, PredI); 1375 builder.generateNode(PrevState, false, PredI); 1376 continue; 1377 } 1378 1379 DefinedSVal V = X.castAs<DefinedSVal>(); 1380 1381 ProgramStateRef StTrue, StFalse; 1382 tie(StTrue, StFalse) = PrevState->assume(V); 1383 1384 // Process the true branch. 1385 if (builder.isFeasible(true)) { 1386 if (StTrue) 1387 builder.generateNode(StTrue, true, PredI); 1388 else 1389 builder.markInfeasible(true); 1390 } 1391 1392 // Process the false branch. 1393 if (builder.isFeasible(false)) { 1394 if (StFalse) 1395 builder.generateNode(StFalse, false, PredI); 1396 else 1397 builder.markInfeasible(false); 1398 } 1399 } 1400 currBldrCtx = 0; 1401} 1402 1403/// The GDM component containing the set of global variables which have been 1404/// previously initialized with explicit initializers. 1405REGISTER_TRAIT_WITH_PROGRAMSTATE(InitializedGlobalsSet, 1406 llvm::ImmutableSet<const VarDecl *>) 1407 1408void ExprEngine::processStaticInitializer(const DeclStmt *DS, 1409 NodeBuilderContext &BuilderCtx, 1410 ExplodedNode *Pred, 1411 clang::ento::ExplodedNodeSet &Dst, 1412 const CFGBlock *DstT, 1413 const CFGBlock *DstF) { 1414 currBldrCtx = &BuilderCtx; 1415 1416 const VarDecl *VD = cast<VarDecl>(DS->getSingleDecl()); 1417 ProgramStateRef state = Pred->getState(); 1418 bool initHasRun = state->contains<InitializedGlobalsSet>(VD); 1419 BranchNodeBuilder builder(Pred, Dst, BuilderCtx, DstT, DstF); 1420 1421 if (!initHasRun) { 1422 state = state->add<InitializedGlobalsSet>(VD); 1423 } 1424 1425 builder.generateNode(state, initHasRun, Pred); 1426 builder.markInfeasible(!initHasRun); 1427 1428 currBldrCtx = 0; 1429} 1430 1431/// processIndirectGoto - Called by CoreEngine. Used to generate successor 1432/// nodes by processing the 'effects' of a computed goto jump. 1433void ExprEngine::processIndirectGoto(IndirectGotoNodeBuilder &builder) { 1434 1435 ProgramStateRef state = builder.getState(); 1436 SVal V = state->getSVal(builder.getTarget(), builder.getLocationContext()); 1437 1438 // Three possibilities: 1439 // 1440 // (1) We know the computed label. 1441 // (2) The label is NULL (or some other constant), or Undefined. 1442 // (3) We have no clue about the label. Dispatch to all targets. 1443 // 1444 1445 typedef IndirectGotoNodeBuilder::iterator iterator; 1446 1447 if (Optional<loc::GotoLabel> LV = V.getAs<loc::GotoLabel>()) { 1448 const LabelDecl *L = LV->getLabel(); 1449 1450 for (iterator I = builder.begin(), E = builder.end(); I != E; ++I) { 1451 if (I.getLabel() == L) { 1452 builder.generateNode(I, state); 1453 return; 1454 } 1455 } 1456 1457 llvm_unreachable("No block with label."); 1458 } 1459 1460 if (V.getAs<loc::ConcreteInt>() || V.getAs<UndefinedVal>()) { 1461 // Dispatch to the first target and mark it as a sink. 1462 //ExplodedNode* N = builder.generateNode(builder.begin(), state, true); 1463 // FIXME: add checker visit. 1464 // UndefBranches.insert(N); 1465 return; 1466 } 1467 1468 // This is really a catch-all. We don't support symbolics yet. 1469 // FIXME: Implement dispatch for symbolic pointers. 1470 1471 for (iterator I=builder.begin(), E=builder.end(); I != E; ++I) 1472 builder.generateNode(I, state); 1473} 1474 1475/// ProcessEndPath - Called by CoreEngine. Used to generate end-of-path 1476/// nodes when the control reaches the end of a function. 1477void ExprEngine::processEndOfFunction(NodeBuilderContext& BC, 1478 ExplodedNode *Pred) { 1479 StateMgr.EndPath(Pred->getState()); 1480 1481 ExplodedNodeSet Dst; 1482 if (Pred->getLocationContext()->inTopFrame()) { 1483 // Remove dead symbols. 1484 ExplodedNodeSet AfterRemovedDead; 1485 removeDeadOnEndOfFunction(BC, Pred, AfterRemovedDead); 1486 1487 // Notify checkers. 1488 for (ExplodedNodeSet::iterator I = AfterRemovedDead.begin(), 1489 E = AfterRemovedDead.end(); I != E; ++I) { 1490 getCheckerManager().runCheckersForEndFunction(BC, Dst, *I, *this); 1491 } 1492 } else { 1493 getCheckerManager().runCheckersForEndFunction(BC, Dst, Pred, *this); 1494 } 1495 1496 Engine.enqueueEndOfFunction(Dst); 1497} 1498 1499/// ProcessSwitch - Called by CoreEngine. Used to generate successor 1500/// nodes by processing the 'effects' of a switch statement. 1501void ExprEngine::processSwitch(SwitchNodeBuilder& builder) { 1502 typedef SwitchNodeBuilder::iterator iterator; 1503 ProgramStateRef state = builder.getState(); 1504 const Expr *CondE = builder.getCondition(); 1505 SVal CondV_untested = state->getSVal(CondE, builder.getLocationContext()); 1506 1507 if (CondV_untested.isUndef()) { 1508 //ExplodedNode* N = builder.generateDefaultCaseNode(state, true); 1509 // FIXME: add checker 1510 //UndefBranches.insert(N); 1511 1512 return; 1513 } 1514 DefinedOrUnknownSVal CondV = CondV_untested.castAs<DefinedOrUnknownSVal>(); 1515 1516 ProgramStateRef DefaultSt = state; 1517 1518 iterator I = builder.begin(), EI = builder.end(); 1519 bool defaultIsFeasible = I == EI; 1520 1521 for ( ; I != EI; ++I) { 1522 // Successor may be pruned out during CFG construction. 1523 if (!I.getBlock()) 1524 continue; 1525 1526 const CaseStmt *Case = I.getCase(); 1527 1528 // Evaluate the LHS of the case value. 1529 llvm::APSInt V1 = Case->getLHS()->EvaluateKnownConstInt(getContext()); 1530 assert(V1.getBitWidth() == getContext().getTypeSize(CondE->getType())); 1531 1532 // Get the RHS of the case, if it exists. 1533 llvm::APSInt V2; 1534 if (const Expr *E = Case->getRHS()) 1535 V2 = E->EvaluateKnownConstInt(getContext()); 1536 else 1537 V2 = V1; 1538 1539 // FIXME: Eventually we should replace the logic below with a range 1540 // comparison, rather than concretize the values within the range. 1541 // This should be easy once we have "ranges" for NonLVals. 1542 1543 do { 1544 nonloc::ConcreteInt CaseVal(getBasicVals().getValue(V1)); 1545 DefinedOrUnknownSVal Res = svalBuilder.evalEQ(DefaultSt ? DefaultSt : state, 1546 CondV, CaseVal); 1547 1548 // Now "assume" that the case matches. 1549 if (ProgramStateRef stateNew = state->assume(Res, true)) { 1550 builder.generateCaseStmtNode(I, stateNew); 1551 1552 // If CondV evaluates to a constant, then we know that this 1553 // is the *only* case that we can take, so stop evaluating the 1554 // others. 1555 if (CondV.getAs<nonloc::ConcreteInt>()) 1556 return; 1557 } 1558 1559 // Now "assume" that the case doesn't match. Add this state 1560 // to the default state (if it is feasible). 1561 if (DefaultSt) { 1562 if (ProgramStateRef stateNew = DefaultSt->assume(Res, false)) { 1563 defaultIsFeasible = true; 1564 DefaultSt = stateNew; 1565 } 1566 else { 1567 defaultIsFeasible = false; 1568 DefaultSt = NULL; 1569 } 1570 } 1571 1572 // Concretize the next value in the range. 1573 if (V1 == V2) 1574 break; 1575 1576 ++V1; 1577 assert (V1 <= V2); 1578 1579 } while (true); 1580 } 1581 1582 if (!defaultIsFeasible) 1583 return; 1584 1585 // If we have switch(enum value), the default branch is not 1586 // feasible if all of the enum constants not covered by 'case:' statements 1587 // are not feasible values for the switch condition. 1588 // 1589 // Note that this isn't as accurate as it could be. Even if there isn't 1590 // a case for a particular enum value as long as that enum value isn't 1591 // feasible then it shouldn't be considered for making 'default:' reachable. 1592 const SwitchStmt *SS = builder.getSwitch(); 1593 const Expr *CondExpr = SS->getCond()->IgnoreParenImpCasts(); 1594 if (CondExpr->getType()->getAs<EnumType>()) { 1595 if (SS->isAllEnumCasesCovered()) 1596 return; 1597 } 1598 1599 builder.generateDefaultCaseNode(DefaultSt); 1600} 1601 1602//===----------------------------------------------------------------------===// 1603// Transfer functions: Loads and stores. 1604//===----------------------------------------------------------------------===// 1605 1606void ExprEngine::VisitCommonDeclRefExpr(const Expr *Ex, const NamedDecl *D, 1607 ExplodedNode *Pred, 1608 ExplodedNodeSet &Dst) { 1609 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx); 1610 1611 ProgramStateRef state = Pred->getState(); 1612 const LocationContext *LCtx = Pred->getLocationContext(); 1613 1614 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1615 assert(Ex->isGLValue()); 1616 SVal V = state->getLValue(VD, Pred->getLocationContext()); 1617 1618 // For references, the 'lvalue' is the pointer address stored in the 1619 // reference region. 1620 if (VD->getType()->isReferenceType()) { 1621 if (const MemRegion *R = V.getAsRegion()) 1622 V = state->getSVal(R); 1623 else 1624 V = UnknownVal(); 1625 } 1626 1627 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), 0, 1628 ProgramPoint::PostLValueKind); 1629 return; 1630 } 1631 if (const EnumConstantDecl *ED = dyn_cast<EnumConstantDecl>(D)) { 1632 assert(!Ex->isGLValue()); 1633 SVal V = svalBuilder.makeIntVal(ED->getInitVal()); 1634 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V)); 1635 return; 1636 } 1637 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1638 SVal V = svalBuilder.getFunctionPointer(FD); 1639 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), 0, 1640 ProgramPoint::PostLValueKind); 1641 return; 1642 } 1643 if (isa<FieldDecl>(D)) { 1644 // FIXME: Compute lvalue of field pointers-to-member. 1645 // Right now we just use a non-null void pointer, so that it gives proper 1646 // results in boolean contexts. 1647 SVal V = svalBuilder.conjureSymbolVal(Ex, LCtx, getContext().VoidPtrTy, 1648 currBldrCtx->blockCount()); 1649 state = state->assume(V.castAs<DefinedOrUnknownSVal>(), true); 1650 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), 0, 1651 ProgramPoint::PostLValueKind); 1652 return; 1653 } 1654 1655 llvm_unreachable("Support for this Decl not implemented."); 1656} 1657 1658/// VisitArraySubscriptExpr - Transfer function for array accesses 1659void ExprEngine::VisitLvalArraySubscriptExpr(const ArraySubscriptExpr *A, 1660 ExplodedNode *Pred, 1661 ExplodedNodeSet &Dst){ 1662 1663 const Expr *Base = A->getBase()->IgnoreParens(); 1664 const Expr *Idx = A->getIdx()->IgnoreParens(); 1665 1666 1667 ExplodedNodeSet checkerPreStmt; 1668 getCheckerManager().runCheckersForPreStmt(checkerPreStmt, Pred, A, *this); 1669 1670 StmtNodeBuilder Bldr(checkerPreStmt, Dst, *currBldrCtx); 1671 1672 for (ExplodedNodeSet::iterator it = checkerPreStmt.begin(), 1673 ei = checkerPreStmt.end(); it != ei; ++it) { 1674 const LocationContext *LCtx = (*it)->getLocationContext(); 1675 ProgramStateRef state = (*it)->getState(); 1676 SVal V = state->getLValue(A->getType(), 1677 state->getSVal(Idx, LCtx), 1678 state->getSVal(Base, LCtx)); 1679 assert(A->isGLValue()); 1680 Bldr.generateNode(A, *it, state->BindExpr(A, LCtx, V), 0, 1681 ProgramPoint::PostLValueKind); 1682 } 1683} 1684 1685/// VisitMemberExpr - Transfer function for member expressions. 1686void ExprEngine::VisitMemberExpr(const MemberExpr *M, ExplodedNode *Pred, 1687 ExplodedNodeSet &TopDst) { 1688 1689 StmtNodeBuilder Bldr(Pred, TopDst, *currBldrCtx); 1690 ExplodedNodeSet Dst; 1691 ValueDecl *Member = M->getMemberDecl(); 1692 1693 // Handle static member variables and enum constants accessed via 1694 // member syntax. 1695 if (isa<VarDecl>(Member) || isa<EnumConstantDecl>(Member)) { 1696 Bldr.takeNodes(Pred); 1697 VisitCommonDeclRefExpr(M, Member, Pred, Dst); 1698 Bldr.addNodes(Dst); 1699 return; 1700 } 1701 1702 ProgramStateRef state = Pred->getState(); 1703 const LocationContext *LCtx = Pred->getLocationContext(); 1704 Expr *BaseExpr = M->getBase(); 1705 1706 // Handle C++ method calls. 1707 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Member)) { 1708 if (MD->isInstance()) 1709 state = createTemporaryRegionIfNeeded(state, LCtx, BaseExpr); 1710 1711 SVal MDVal = svalBuilder.getFunctionPointer(MD); 1712 state = state->BindExpr(M, LCtx, MDVal); 1713 1714 Bldr.generateNode(M, Pred, state); 1715 return; 1716 } 1717 1718 // Handle regular struct fields / member variables. 1719 state = createTemporaryRegionIfNeeded(state, LCtx, BaseExpr); 1720 SVal baseExprVal = state->getSVal(BaseExpr, LCtx); 1721 1722 FieldDecl *field = cast<FieldDecl>(Member); 1723 SVal L = state->getLValue(field, baseExprVal); 1724 if (M->isGLValue()) { 1725 if (field->getType()->isReferenceType()) { 1726 if (const MemRegion *R = L.getAsRegion()) 1727 L = state->getSVal(R); 1728 else 1729 L = UnknownVal(); 1730 } 1731 1732 Bldr.generateNode(M, Pred, state->BindExpr(M, LCtx, L), 0, 1733 ProgramPoint::PostLValueKind); 1734 } else { 1735 Bldr.takeNodes(Pred); 1736 evalLoad(Dst, M, M, Pred, state, L); 1737 Bldr.addNodes(Dst); 1738 } 1739} 1740 1741namespace { 1742class CollectReachableSymbolsCallback : public SymbolVisitor { 1743 InvalidatedSymbols Symbols; 1744public: 1745 CollectReachableSymbolsCallback(ProgramStateRef State) {} 1746 const InvalidatedSymbols &getSymbols() const { return Symbols; } 1747 1748 bool VisitSymbol(SymbolRef Sym) { 1749 Symbols.insert(Sym); 1750 return true; 1751 } 1752}; 1753} // end anonymous namespace 1754 1755// A value escapes in three possible cases: 1756// (1) We are binding to something that is not a memory region. 1757// (2) We are binding to a MemrRegion that does not have stack storage. 1758// (3) We are binding to a MemRegion with stack storage that the store 1759// does not understand. 1760ProgramStateRef ExprEngine::processPointerEscapedOnBind(ProgramStateRef State, 1761 SVal Loc, SVal Val) { 1762 // Are we storing to something that causes the value to "escape"? 1763 bool escapes = true; 1764 1765 // TODO: Move to StoreManager. 1766 if (Optional<loc::MemRegionVal> regionLoc = Loc.getAs<loc::MemRegionVal>()) { 1767 escapes = !regionLoc->getRegion()->hasStackStorage(); 1768 1769 if (!escapes) { 1770 // To test (3), generate a new state with the binding added. If it is 1771 // the same state, then it escapes (since the store cannot represent 1772 // the binding). 1773 // Do this only if we know that the store is not supposed to generate the 1774 // same state. 1775 SVal StoredVal = State->getSVal(regionLoc->getRegion()); 1776 if (StoredVal != Val) 1777 escapes = (State == (State->bindLoc(*regionLoc, Val))); 1778 } 1779 } 1780 1781 // If our store can represent the binding and we aren't storing to something 1782 // that doesn't have local storage then just return and have the simulation 1783 // state continue as is. 1784 if (!escapes) 1785 return State; 1786 1787 // Otherwise, find all symbols referenced by 'val' that we are tracking 1788 // and stop tracking them. 1789 CollectReachableSymbolsCallback Scanner = 1790 State->scanReachableSymbols<CollectReachableSymbolsCallback>(Val); 1791 const InvalidatedSymbols &EscapedSymbols = Scanner.getSymbols(); 1792 State = getCheckerManager().runCheckersForPointerEscape(State, 1793 EscapedSymbols, 1794 /*CallEvent*/ 0, 1795 PSK_EscapeOnBind); 1796 1797 return State; 1798} 1799 1800ProgramStateRef 1801ExprEngine::notifyCheckersOfPointerEscape(ProgramStateRef State, 1802 const InvalidatedSymbols *Invalidated, 1803 ArrayRef<const MemRegion *> ExplicitRegions, 1804 ArrayRef<const MemRegion *> Regions, 1805 const CallEvent *Call, 1806 bool IsConst) { 1807 1808 if (!Invalidated || Invalidated->empty()) 1809 return State; 1810 1811 if (!Call) 1812 return getCheckerManager().runCheckersForPointerEscape(State, 1813 *Invalidated, 1814 0, 1815 PSK_EscapeOther, 1816 IsConst); 1817 1818 // Note: Due to current limitations of RegionStore, we only process the top 1819 // level const pointers correctly. The lower level const pointers are 1820 // currently treated as non-const. 1821 if (IsConst) 1822 return getCheckerManager().runCheckersForPointerEscape(State, 1823 *Invalidated, 1824 Call, 1825 PSK_DirectEscapeOnCall, 1826 true); 1827 1828 // If the symbols were invalidated by a call, we want to find out which ones 1829 // were invalidated directly due to being arguments to the call. 1830 InvalidatedSymbols SymbolsDirectlyInvalidated; 1831 for (ArrayRef<const MemRegion *>::iterator I = ExplicitRegions.begin(), 1832 E = ExplicitRegions.end(); I != E; ++I) { 1833 if (const SymbolicRegion *R = (*I)->StripCasts()->getAs<SymbolicRegion>()) 1834 SymbolsDirectlyInvalidated.insert(R->getSymbol()); 1835 } 1836 1837 InvalidatedSymbols SymbolsIndirectlyInvalidated; 1838 for (InvalidatedSymbols::const_iterator I=Invalidated->begin(), 1839 E = Invalidated->end(); I!=E; ++I) { 1840 SymbolRef sym = *I; 1841 if (SymbolsDirectlyInvalidated.count(sym)) 1842 continue; 1843 SymbolsIndirectlyInvalidated.insert(sym); 1844 } 1845 1846 if (!SymbolsDirectlyInvalidated.empty()) 1847 State = getCheckerManager().runCheckersForPointerEscape(State, 1848 SymbolsDirectlyInvalidated, Call, PSK_DirectEscapeOnCall); 1849 1850 // Notify about the symbols that get indirectly invalidated by the call. 1851 if (!SymbolsIndirectlyInvalidated.empty()) 1852 State = getCheckerManager().runCheckersForPointerEscape(State, 1853 SymbolsIndirectlyInvalidated, Call, PSK_IndirectEscapeOnCall); 1854 1855 return State; 1856} 1857 1858/// evalBind - Handle the semantics of binding a value to a specific location. 1859/// This method is used by evalStore and (soon) VisitDeclStmt, and others. 1860void ExprEngine::evalBind(ExplodedNodeSet &Dst, const Stmt *StoreE, 1861 ExplodedNode *Pred, 1862 SVal location, SVal Val, 1863 bool atDeclInit, const ProgramPoint *PP) { 1864 1865 const LocationContext *LC = Pred->getLocationContext(); 1866 PostStmt PS(StoreE, LC); 1867 if (!PP) 1868 PP = &PS; 1869 1870 // Do a previsit of the bind. 1871 ExplodedNodeSet CheckedSet; 1872 getCheckerManager().runCheckersForBind(CheckedSet, Pred, location, Val, 1873 StoreE, *this, *PP); 1874 1875 1876 StmtNodeBuilder Bldr(CheckedSet, Dst, *currBldrCtx); 1877 1878 // If the location is not a 'Loc', it will already be handled by 1879 // the checkers. There is nothing left to do. 1880 if (!location.getAs<Loc>()) { 1881 const ProgramPoint L = PostStore(StoreE, LC, /*Loc*/0, /*tag*/0); 1882 ProgramStateRef state = Pred->getState(); 1883 state = processPointerEscapedOnBind(state, location, Val); 1884 Bldr.generateNode(L, state, Pred); 1885 return; 1886 } 1887 1888 1889 for (ExplodedNodeSet::iterator I = CheckedSet.begin(), E = CheckedSet.end(); 1890 I!=E; ++I) { 1891 ExplodedNode *PredI = *I; 1892 ProgramStateRef state = PredI->getState(); 1893 1894 state = processPointerEscapedOnBind(state, location, Val); 1895 1896 // When binding the value, pass on the hint that this is a initialization. 1897 // For initializations, we do not need to inform clients of region 1898 // changes. 1899 state = state->bindLoc(location.castAs<Loc>(), 1900 Val, /* notifyChanges = */ !atDeclInit); 1901 1902 const MemRegion *LocReg = 0; 1903 if (Optional<loc::MemRegionVal> LocRegVal = 1904 location.getAs<loc::MemRegionVal>()) { 1905 LocReg = LocRegVal->getRegion(); 1906 } 1907 1908 const ProgramPoint L = PostStore(StoreE, LC, LocReg, 0); 1909 Bldr.generateNode(L, state, PredI); 1910 } 1911} 1912 1913/// evalStore - Handle the semantics of a store via an assignment. 1914/// @param Dst The node set to store generated state nodes 1915/// @param AssignE The assignment expression if the store happens in an 1916/// assignment. 1917/// @param LocationE The location expression that is stored to. 1918/// @param state The current simulation state 1919/// @param location The location to store the value 1920/// @param Val The value to be stored 1921void ExprEngine::evalStore(ExplodedNodeSet &Dst, const Expr *AssignE, 1922 const Expr *LocationE, 1923 ExplodedNode *Pred, 1924 ProgramStateRef state, SVal location, SVal Val, 1925 const ProgramPointTag *tag) { 1926 // Proceed with the store. We use AssignE as the anchor for the PostStore 1927 // ProgramPoint if it is non-NULL, and LocationE otherwise. 1928 const Expr *StoreE = AssignE ? AssignE : LocationE; 1929 1930 // Evaluate the location (checks for bad dereferences). 1931 ExplodedNodeSet Tmp; 1932 evalLocation(Tmp, AssignE, LocationE, Pred, state, location, tag, false); 1933 1934 if (Tmp.empty()) 1935 return; 1936 1937 if (location.isUndef()) 1938 return; 1939 1940 for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI) 1941 evalBind(Dst, StoreE, *NI, location, Val, false); 1942} 1943 1944void ExprEngine::evalLoad(ExplodedNodeSet &Dst, 1945 const Expr *NodeEx, 1946 const Expr *BoundEx, 1947 ExplodedNode *Pred, 1948 ProgramStateRef state, 1949 SVal location, 1950 const ProgramPointTag *tag, 1951 QualType LoadTy) 1952{ 1953 assert(!location.getAs<NonLoc>() && "location cannot be a NonLoc."); 1954 1955 // Are we loading from a region? This actually results in two loads; one 1956 // to fetch the address of the referenced value and one to fetch the 1957 // referenced value. 1958 if (const TypedValueRegion *TR = 1959 dyn_cast_or_null<TypedValueRegion>(location.getAsRegion())) { 1960 1961 QualType ValTy = TR->getValueType(); 1962 if (const ReferenceType *RT = ValTy->getAs<ReferenceType>()) { 1963 static SimpleProgramPointTag 1964 loadReferenceTag("ExprEngine : Load Reference"); 1965 ExplodedNodeSet Tmp; 1966 evalLoadCommon(Tmp, NodeEx, BoundEx, Pred, state, 1967 location, &loadReferenceTag, 1968 getContext().getPointerType(RT->getPointeeType())); 1969 1970 // Perform the load from the referenced value. 1971 for (ExplodedNodeSet::iterator I=Tmp.begin(), E=Tmp.end() ; I!=E; ++I) { 1972 state = (*I)->getState(); 1973 location = state->getSVal(BoundEx, (*I)->getLocationContext()); 1974 evalLoadCommon(Dst, NodeEx, BoundEx, *I, state, location, tag, LoadTy); 1975 } 1976 return; 1977 } 1978 } 1979 1980 evalLoadCommon(Dst, NodeEx, BoundEx, Pred, state, location, tag, LoadTy); 1981} 1982 1983void ExprEngine::evalLoadCommon(ExplodedNodeSet &Dst, 1984 const Expr *NodeEx, 1985 const Expr *BoundEx, 1986 ExplodedNode *Pred, 1987 ProgramStateRef state, 1988 SVal location, 1989 const ProgramPointTag *tag, 1990 QualType LoadTy) { 1991 assert(NodeEx); 1992 assert(BoundEx); 1993 // Evaluate the location (checks for bad dereferences). 1994 ExplodedNodeSet Tmp; 1995 evalLocation(Tmp, NodeEx, BoundEx, Pred, state, location, tag, true); 1996 if (Tmp.empty()) 1997 return; 1998 1999 StmtNodeBuilder Bldr(Tmp, Dst, *currBldrCtx); 2000 if (location.isUndef()) 2001 return; 2002 2003 // Proceed with the load. 2004 for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI) { 2005 state = (*NI)->getState(); 2006 const LocationContext *LCtx = (*NI)->getLocationContext(); 2007 2008 SVal V = UnknownVal(); 2009 if (location.isValid()) { 2010 if (LoadTy.isNull()) 2011 LoadTy = BoundEx->getType(); 2012 V = state->getSVal(location.castAs<Loc>(), LoadTy); 2013 } 2014 2015 Bldr.generateNode(NodeEx, *NI, state->BindExpr(BoundEx, LCtx, V), tag, 2016 ProgramPoint::PostLoadKind); 2017 } 2018} 2019 2020void ExprEngine::evalLocation(ExplodedNodeSet &Dst, 2021 const Stmt *NodeEx, 2022 const Stmt *BoundEx, 2023 ExplodedNode *Pred, 2024 ProgramStateRef state, 2025 SVal location, 2026 const ProgramPointTag *tag, 2027 bool isLoad) { 2028 StmtNodeBuilder BldrTop(Pred, Dst, *currBldrCtx); 2029 // Early checks for performance reason. 2030 if (location.isUnknown()) { 2031 return; 2032 } 2033 2034 ExplodedNodeSet Src; 2035 BldrTop.takeNodes(Pred); 2036 StmtNodeBuilder Bldr(Pred, Src, *currBldrCtx); 2037 if (Pred->getState() != state) { 2038 // Associate this new state with an ExplodedNode. 2039 // FIXME: If I pass null tag, the graph is incorrect, e.g for 2040 // int *p; 2041 // p = 0; 2042 // *p = 0xDEADBEEF; 2043 // "p = 0" is not noted as "Null pointer value stored to 'p'" but 2044 // instead "int *p" is noted as 2045 // "Variable 'p' initialized to a null pointer value" 2046 2047 static SimpleProgramPointTag tag("ExprEngine: Location"); 2048 Bldr.generateNode(NodeEx, Pred, state, &tag); 2049 } 2050 ExplodedNodeSet Tmp; 2051 getCheckerManager().runCheckersForLocation(Tmp, Src, location, isLoad, 2052 NodeEx, BoundEx, *this); 2053 BldrTop.addNodes(Tmp); 2054} 2055 2056std::pair<const ProgramPointTag *, const ProgramPointTag*> 2057ExprEngine::geteagerlyAssumeBinOpBifurcationTags() { 2058 static SimpleProgramPointTag 2059 eagerlyAssumeBinOpBifurcationTrue("ExprEngine : Eagerly Assume True"), 2060 eagerlyAssumeBinOpBifurcationFalse("ExprEngine : Eagerly Assume False"); 2061 return std::make_pair(&eagerlyAssumeBinOpBifurcationTrue, 2062 &eagerlyAssumeBinOpBifurcationFalse); 2063} 2064 2065void ExprEngine::evalEagerlyAssumeBinOpBifurcation(ExplodedNodeSet &Dst, 2066 ExplodedNodeSet &Src, 2067 const Expr *Ex) { 2068 StmtNodeBuilder Bldr(Src, Dst, *currBldrCtx); 2069 2070 for (ExplodedNodeSet::iterator I=Src.begin(), E=Src.end(); I!=E; ++I) { 2071 ExplodedNode *Pred = *I; 2072 // Test if the previous node was as the same expression. This can happen 2073 // when the expression fails to evaluate to anything meaningful and 2074 // (as an optimization) we don't generate a node. 2075 ProgramPoint P = Pred->getLocation(); 2076 if (!P.getAs<PostStmt>() || P.castAs<PostStmt>().getStmt() != Ex) { 2077 continue; 2078 } 2079 2080 ProgramStateRef state = Pred->getState(); 2081 SVal V = state->getSVal(Ex, Pred->getLocationContext()); 2082 Optional<nonloc::SymbolVal> SEV = V.getAs<nonloc::SymbolVal>(); 2083 if (SEV && SEV->isExpression()) { 2084 const std::pair<const ProgramPointTag *, const ProgramPointTag*> &tags = 2085 geteagerlyAssumeBinOpBifurcationTags(); 2086 2087 ProgramStateRef StateTrue, StateFalse; 2088 tie(StateTrue, StateFalse) = state->assume(*SEV); 2089 2090 // First assume that the condition is true. 2091 if (StateTrue) { 2092 SVal Val = svalBuilder.makeIntVal(1U, Ex->getType()); 2093 StateTrue = StateTrue->BindExpr(Ex, Pred->getLocationContext(), Val); 2094 Bldr.generateNode(Ex, Pred, StateTrue, tags.first); 2095 } 2096 2097 // Next, assume that the condition is false. 2098 if (StateFalse) { 2099 SVal Val = svalBuilder.makeIntVal(0U, Ex->getType()); 2100 StateFalse = StateFalse->BindExpr(Ex, Pred->getLocationContext(), Val); 2101 Bldr.generateNode(Ex, Pred, StateFalse, tags.second); 2102 } 2103 } 2104 } 2105} 2106 2107void ExprEngine::VisitGCCAsmStmt(const GCCAsmStmt *A, ExplodedNode *Pred, 2108 ExplodedNodeSet &Dst) { 2109 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx); 2110 // We have processed both the inputs and the outputs. All of the outputs 2111 // should evaluate to Locs. Nuke all of their values. 2112 2113 // FIXME: Some day in the future it would be nice to allow a "plug-in" 2114 // which interprets the inline asm and stores proper results in the 2115 // outputs. 2116 2117 ProgramStateRef state = Pred->getState(); 2118 2119 for (GCCAsmStmt::const_outputs_iterator OI = A->begin_outputs(), 2120 OE = A->end_outputs(); OI != OE; ++OI) { 2121 SVal X = state->getSVal(*OI, Pred->getLocationContext()); 2122 assert (!X.getAs<NonLoc>()); // Should be an Lval, or unknown, undef. 2123 2124 if (Optional<Loc> LV = X.getAs<Loc>()) 2125 state = state->bindLoc(*LV, UnknownVal()); 2126 } 2127 2128 Bldr.generateNode(A, Pred, state); 2129} 2130 2131void ExprEngine::VisitMSAsmStmt(const MSAsmStmt *A, ExplodedNode *Pred, 2132 ExplodedNodeSet &Dst) { 2133 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx); 2134 Bldr.generateNode(A, Pred, Pred->getState()); 2135} 2136 2137//===----------------------------------------------------------------------===// 2138// Visualization. 2139//===----------------------------------------------------------------------===// 2140 2141#ifndef NDEBUG 2142static ExprEngine* GraphPrintCheckerState; 2143static SourceManager* GraphPrintSourceManager; 2144 2145namespace llvm { 2146template<> 2147struct DOTGraphTraits<ExplodedNode*> : 2148 public DefaultDOTGraphTraits { 2149 2150 DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {} 2151 2152 // FIXME: Since we do not cache error nodes in ExprEngine now, this does not 2153 // work. 2154 static std::string getNodeAttributes(const ExplodedNode *N, void*) { 2155 2156#if 0 2157 // FIXME: Replace with a general scheme to tell if the node is 2158 // an error node. 2159 if (GraphPrintCheckerState->isImplicitNullDeref(N) || 2160 GraphPrintCheckerState->isExplicitNullDeref(N) || 2161 GraphPrintCheckerState->isUndefDeref(N) || 2162 GraphPrintCheckerState->isUndefStore(N) || 2163 GraphPrintCheckerState->isUndefControlFlow(N) || 2164 GraphPrintCheckerState->isUndefResult(N) || 2165 GraphPrintCheckerState->isBadCall(N) || 2166 GraphPrintCheckerState->isUndefArg(N)) 2167 return "color=\"red\",style=\"filled\""; 2168 2169 if (GraphPrintCheckerState->isNoReturnCall(N)) 2170 return "color=\"blue\",style=\"filled\""; 2171#endif 2172 return ""; 2173 } 2174 2175 static void printLocation(raw_ostream &Out, SourceLocation SLoc) { 2176 if (SLoc.isFileID()) { 2177 Out << "\\lline=" 2178 << GraphPrintSourceManager->getExpansionLineNumber(SLoc) 2179 << " col=" 2180 << GraphPrintSourceManager->getExpansionColumnNumber(SLoc) 2181 << "\\l"; 2182 } 2183 } 2184 2185 static std::string getNodeLabel(const ExplodedNode *N, void*){ 2186 2187 std::string sbuf; 2188 llvm::raw_string_ostream Out(sbuf); 2189 2190 // Program Location. 2191 ProgramPoint Loc = N->getLocation(); 2192 2193 switch (Loc.getKind()) { 2194 case ProgramPoint::BlockEntranceKind: { 2195 Out << "Block Entrance: B" 2196 << Loc.castAs<BlockEntrance>().getBlock()->getBlockID(); 2197 if (const NamedDecl *ND = 2198 dyn_cast<NamedDecl>(Loc.getLocationContext()->getDecl())) { 2199 Out << " ("; 2200 ND->printName(Out); 2201 Out << ")"; 2202 } 2203 break; 2204 } 2205 2206 case ProgramPoint::BlockExitKind: 2207 assert (false); 2208 break; 2209 2210 case ProgramPoint::CallEnterKind: 2211 Out << "CallEnter"; 2212 break; 2213 2214 case ProgramPoint::CallExitBeginKind: 2215 Out << "CallExitBegin"; 2216 break; 2217 2218 case ProgramPoint::CallExitEndKind: 2219 Out << "CallExitEnd"; 2220 break; 2221 2222 case ProgramPoint::PostStmtPurgeDeadSymbolsKind: 2223 Out << "PostStmtPurgeDeadSymbols"; 2224 break; 2225 2226 case ProgramPoint::PreStmtPurgeDeadSymbolsKind: 2227 Out << "PreStmtPurgeDeadSymbols"; 2228 break; 2229 2230 case ProgramPoint::EpsilonKind: 2231 Out << "Epsilon Point"; 2232 break; 2233 2234 case ProgramPoint::PreImplicitCallKind: { 2235 ImplicitCallPoint PC = Loc.castAs<ImplicitCallPoint>(); 2236 Out << "PreCall: "; 2237 2238 // FIXME: Get proper printing options. 2239 PC.getDecl()->print(Out, LangOptions()); 2240 printLocation(Out, PC.getLocation()); 2241 break; 2242 } 2243 2244 case ProgramPoint::PostImplicitCallKind: { 2245 ImplicitCallPoint PC = Loc.castAs<ImplicitCallPoint>(); 2246 Out << "PostCall: "; 2247 2248 // FIXME: Get proper printing options. 2249 PC.getDecl()->print(Out, LangOptions()); 2250 printLocation(Out, PC.getLocation()); 2251 break; 2252 } 2253 2254 case ProgramPoint::PostInitializerKind: { 2255 Out << "PostInitializer: "; 2256 const CXXCtorInitializer *Init = 2257 Loc.castAs<PostInitializer>().getInitializer(); 2258 if (const FieldDecl *FD = Init->getAnyMember()) 2259 Out << *FD; 2260 else { 2261 QualType Ty = Init->getTypeSourceInfo()->getType(); 2262 Ty = Ty.getLocalUnqualifiedType(); 2263 LangOptions LO; // FIXME. 2264 Ty.print(Out, LO); 2265 } 2266 break; 2267 } 2268 2269 case ProgramPoint::BlockEdgeKind: { 2270 const BlockEdge &E = Loc.castAs<BlockEdge>(); 2271 Out << "Edge: (B" << E.getSrc()->getBlockID() << ", B" 2272 << E.getDst()->getBlockID() << ')'; 2273 2274 if (const Stmt *T = E.getSrc()->getTerminator()) { 2275 SourceLocation SLoc = T->getLocStart(); 2276 2277 Out << "\\|Terminator: "; 2278 LangOptions LO; // FIXME. 2279 E.getSrc()->printTerminator(Out, LO); 2280 2281 if (SLoc.isFileID()) { 2282 Out << "\\lline=" 2283 << GraphPrintSourceManager->getExpansionLineNumber(SLoc) 2284 << " col=" 2285 << GraphPrintSourceManager->getExpansionColumnNumber(SLoc); 2286 } 2287 2288 if (isa<SwitchStmt>(T)) { 2289 const Stmt *Label = E.getDst()->getLabel(); 2290 2291 if (Label) { 2292 if (const CaseStmt *C = dyn_cast<CaseStmt>(Label)) { 2293 Out << "\\lcase "; 2294 LangOptions LO; // FIXME. 2295 C->getLHS()->printPretty(Out, 0, PrintingPolicy(LO)); 2296 2297 if (const Stmt *RHS = C->getRHS()) { 2298 Out << " .. "; 2299 RHS->printPretty(Out, 0, PrintingPolicy(LO)); 2300 } 2301 2302 Out << ":"; 2303 } 2304 else { 2305 assert (isa<DefaultStmt>(Label)); 2306 Out << "\\ldefault:"; 2307 } 2308 } 2309 else 2310 Out << "\\l(implicit) default:"; 2311 } 2312 else if (isa<IndirectGotoStmt>(T)) { 2313 // FIXME 2314 } 2315 else { 2316 Out << "\\lCondition: "; 2317 if (*E.getSrc()->succ_begin() == E.getDst()) 2318 Out << "true"; 2319 else 2320 Out << "false"; 2321 } 2322 2323 Out << "\\l"; 2324 } 2325 2326#if 0 2327 // FIXME: Replace with a general scheme to determine 2328 // the name of the check. 2329 if (GraphPrintCheckerState->isUndefControlFlow(N)) { 2330 Out << "\\|Control-flow based on\\lUndefined value.\\l"; 2331 } 2332#endif 2333 break; 2334 } 2335 2336 default: { 2337 const Stmt *S = Loc.castAs<StmtPoint>().getStmt(); 2338 2339 Out << S->getStmtClassName() << ' ' << (const void*) S << ' '; 2340 LangOptions LO; // FIXME. 2341 S->printPretty(Out, 0, PrintingPolicy(LO)); 2342 printLocation(Out, S->getLocStart()); 2343 2344 if (Loc.getAs<PreStmt>()) 2345 Out << "\\lPreStmt\\l;"; 2346 else if (Loc.getAs<PostLoad>()) 2347 Out << "\\lPostLoad\\l;"; 2348 else if (Loc.getAs<PostStore>()) 2349 Out << "\\lPostStore\\l"; 2350 else if (Loc.getAs<PostLValue>()) 2351 Out << "\\lPostLValue\\l"; 2352 2353#if 0 2354 // FIXME: Replace with a general scheme to determine 2355 // the name of the check. 2356 if (GraphPrintCheckerState->isImplicitNullDeref(N)) 2357 Out << "\\|Implicit-Null Dereference.\\l"; 2358 else if (GraphPrintCheckerState->isExplicitNullDeref(N)) 2359 Out << "\\|Explicit-Null Dereference.\\l"; 2360 else if (GraphPrintCheckerState->isUndefDeref(N)) 2361 Out << "\\|Dereference of undefialied value.\\l"; 2362 else if (GraphPrintCheckerState->isUndefStore(N)) 2363 Out << "\\|Store to Undefined Loc."; 2364 else if (GraphPrintCheckerState->isUndefResult(N)) 2365 Out << "\\|Result of operation is undefined."; 2366 else if (GraphPrintCheckerState->isNoReturnCall(N)) 2367 Out << "\\|Call to function marked \"noreturn\"."; 2368 else if (GraphPrintCheckerState->isBadCall(N)) 2369 Out << "\\|Call to NULL/Undefined."; 2370 else if (GraphPrintCheckerState->isUndefArg(N)) 2371 Out << "\\|Argument in call is undefined"; 2372#endif 2373 2374 break; 2375 } 2376 } 2377 2378 ProgramStateRef state = N->getState(); 2379 Out << "\\|StateID: " << (const void*) state.getPtr() 2380 << " NodeID: " << (const void*) N << "\\|"; 2381 state->printDOT(Out); 2382 2383 Out << "\\l"; 2384 2385 if (const ProgramPointTag *tag = Loc.getTag()) { 2386 Out << "\\|Tag: " << tag->getTagDescription(); 2387 Out << "\\l"; 2388 } 2389 return Out.str(); 2390 } 2391}; 2392} // end llvm namespace 2393#endif 2394 2395#ifndef NDEBUG 2396template <typename ITERATOR> 2397ExplodedNode *GetGraphNode(ITERATOR I) { return *I; } 2398 2399template <> ExplodedNode* 2400GetGraphNode<llvm::DenseMap<ExplodedNode*, Expr*>::iterator> 2401 (llvm::DenseMap<ExplodedNode*, Expr*>::iterator I) { 2402 return I->first; 2403} 2404#endif 2405 2406void ExprEngine::ViewGraph(bool trim) { 2407#ifndef NDEBUG 2408 if (trim) { 2409 std::vector<const ExplodedNode*> Src; 2410 2411 // Flush any outstanding reports to make sure we cover all the nodes. 2412 // This does not cause them to get displayed. 2413 for (BugReporter::iterator I=BR.begin(), E=BR.end(); I!=E; ++I) 2414 const_cast<BugType*>(*I)->FlushReports(BR); 2415 2416 // Iterate through the reports and get their nodes. 2417 for (BugReporter::EQClasses_iterator 2418 EI = BR.EQClasses_begin(), EE = BR.EQClasses_end(); EI != EE; ++EI) { 2419 ExplodedNode *N = const_cast<ExplodedNode*>(EI->begin()->getErrorNode()); 2420 if (N) Src.push_back(N); 2421 } 2422 2423 ViewGraph(Src); 2424 } 2425 else { 2426 GraphPrintCheckerState = this; 2427 GraphPrintSourceManager = &getContext().getSourceManager(); 2428 2429 llvm::ViewGraph(*G.roots_begin(), "ExprEngine"); 2430 2431 GraphPrintCheckerState = NULL; 2432 GraphPrintSourceManager = NULL; 2433 } 2434#endif 2435} 2436 2437void ExprEngine::ViewGraph(ArrayRef<const ExplodedNode*> Nodes) { 2438#ifndef NDEBUG 2439 GraphPrintCheckerState = this; 2440 GraphPrintSourceManager = &getContext().getSourceManager(); 2441 2442 OwningPtr<ExplodedGraph> TrimmedG(G.trim(Nodes)); 2443 2444 if (!TrimmedG.get()) 2445 llvm::errs() << "warning: Trimmed ExplodedGraph is empty.\n"; 2446 else 2447 llvm::ViewGraph(*TrimmedG->roots_begin(), "TrimmedExprEngine"); 2448 2449 GraphPrintCheckerState = NULL; 2450 GraphPrintSourceManager = NULL; 2451#endif 2452} 2453