ExprEngine.cpp revision 7c3e615f01e8f9f587315800fdaf2305ed824568
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::CXXStdInitializerListExprClass: 611 case Stmt::CXXTryStmtClass: 612 case Stmt::CXXTypeidExprClass: 613 case Stmt::CXXUuidofExprClass: 614 case Stmt::MSPropertyRefExprClass: 615 case Stmt::CXXUnresolvedConstructExprClass: 616 case Stmt::DependentScopeDeclRefExprClass: 617 case Stmt::UnaryTypeTraitExprClass: 618 case Stmt::BinaryTypeTraitExprClass: 619 case Stmt::TypeTraitExprClass: 620 case Stmt::ArrayTypeTraitExprClass: 621 case Stmt::ExpressionTraitExprClass: 622 case Stmt::UnresolvedLookupExprClass: 623 case Stmt::UnresolvedMemberExprClass: 624 case Stmt::CXXNoexceptExprClass: 625 case Stmt::PackExpansionExprClass: 626 case Stmt::SubstNonTypeTemplateParmPackExprClass: 627 case Stmt::FunctionParmPackExprClass: 628 case Stmt::SEHTryStmtClass: 629 case Stmt::SEHExceptStmtClass: 630 case Stmt::LambdaExprClass: 631 case Stmt::SEHFinallyStmtClass: { 632 const ExplodedNode *node = Bldr.generateSink(S, Pred, Pred->getState()); 633 Engine.addAbortedBlock(node, currBldrCtx->getBlock()); 634 break; 635 } 636 637 case Stmt::ParenExprClass: 638 llvm_unreachable("ParenExprs already handled."); 639 case Stmt::GenericSelectionExprClass: 640 llvm_unreachable("GenericSelectionExprs already handled."); 641 // Cases that should never be evaluated simply because they shouldn't 642 // appear in the CFG. 643 case Stmt::BreakStmtClass: 644 case Stmt::CaseStmtClass: 645 case Stmt::CompoundStmtClass: 646 case Stmt::ContinueStmtClass: 647 case Stmt::CXXForRangeStmtClass: 648 case Stmt::DefaultStmtClass: 649 case Stmt::DoStmtClass: 650 case Stmt::ForStmtClass: 651 case Stmt::GotoStmtClass: 652 case Stmt::IfStmtClass: 653 case Stmt::IndirectGotoStmtClass: 654 case Stmt::LabelStmtClass: 655 case Stmt::AttributedStmtClass: 656 case Stmt::NoStmtClass: 657 case Stmt::NullStmtClass: 658 case Stmt::SwitchStmtClass: 659 case Stmt::WhileStmtClass: 660 case Expr::MSDependentExistsStmtClass: 661 case Stmt::CapturedStmtClass: 662 llvm_unreachable("Stmt should not be in analyzer evaluation loop"); 663 664 case Stmt::ObjCSubscriptRefExprClass: 665 case Stmt::ObjCPropertyRefExprClass: 666 llvm_unreachable("These are handled by PseudoObjectExpr"); 667 668 case Stmt::GNUNullExprClass: { 669 // GNU __null is a pointer-width integer, not an actual pointer. 670 ProgramStateRef state = Pred->getState(); 671 state = state->BindExpr(S, Pred->getLocationContext(), 672 svalBuilder.makeIntValWithPtrWidth(0, false)); 673 Bldr.generateNode(S, Pred, state); 674 break; 675 } 676 677 case Stmt::ObjCAtSynchronizedStmtClass: 678 Bldr.takeNodes(Pred); 679 VisitObjCAtSynchronizedStmt(cast<ObjCAtSynchronizedStmt>(S), Pred, Dst); 680 Bldr.addNodes(Dst); 681 break; 682 683 case Stmt::ExprWithCleanupsClass: 684 // Handled due to fully linearised CFG. 685 break; 686 687 // Cases not handled yet; but will handle some day. 688 case Stmt::DesignatedInitExprClass: 689 case Stmt::ExtVectorElementExprClass: 690 case Stmt::ImaginaryLiteralClass: 691 case Stmt::ObjCAtCatchStmtClass: 692 case Stmt::ObjCAtFinallyStmtClass: 693 case Stmt::ObjCAtTryStmtClass: 694 case Stmt::ObjCAutoreleasePoolStmtClass: 695 case Stmt::ObjCEncodeExprClass: 696 case Stmt::ObjCIsaExprClass: 697 case Stmt::ObjCProtocolExprClass: 698 case Stmt::ObjCSelectorExprClass: 699 case Stmt::ParenListExprClass: 700 case Stmt::PredefinedExprClass: 701 case Stmt::ShuffleVectorExprClass: 702 case Stmt::VAArgExprClass: 703 case Stmt::CUDAKernelCallExprClass: 704 case Stmt::OpaqueValueExprClass: 705 case Stmt::AsTypeExprClass: 706 case Stmt::AtomicExprClass: 707 // Fall through. 708 709 // Cases we intentionally don't evaluate, since they don't need 710 // to be explicitly evaluated. 711 case Stmt::AddrLabelExprClass: 712 case Stmt::IntegerLiteralClass: 713 case Stmt::CharacterLiteralClass: 714 case Stmt::ImplicitValueInitExprClass: 715 case Stmt::CXXScalarValueInitExprClass: 716 case Stmt::CXXBoolLiteralExprClass: 717 case Stmt::ObjCBoolLiteralExprClass: 718 case Stmt::FloatingLiteralClass: 719 case Stmt::SizeOfPackExprClass: 720 case Stmt::StringLiteralClass: 721 case Stmt::ObjCStringLiteralClass: 722 case Stmt::CXXBindTemporaryExprClass: 723 case Stmt::SubstNonTypeTemplateParmExprClass: 724 case Stmt::CXXNullPtrLiteralExprClass: { 725 Bldr.takeNodes(Pred); 726 ExplodedNodeSet preVisit; 727 getCheckerManager().runCheckersForPreStmt(preVisit, Pred, S, *this); 728 getCheckerManager().runCheckersForPostStmt(Dst, preVisit, S, *this); 729 Bldr.addNodes(Dst); 730 break; 731 } 732 733 case Stmt::CXXDefaultArgExprClass: { 734 Bldr.takeNodes(Pred); 735 ExplodedNodeSet PreVisit; 736 getCheckerManager().runCheckersForPreStmt(PreVisit, Pred, S, *this); 737 738 ExplodedNodeSet Tmp; 739 StmtNodeBuilder Bldr2(PreVisit, Tmp, *currBldrCtx); 740 741 const LocationContext *LCtx = Pred->getLocationContext(); 742 const CXXDefaultArgExpr *DefaultE = cast<CXXDefaultArgExpr>(S); 743 const Expr *ArgE = DefaultE->getExpr(); 744 745 bool IsTemporary = false; 746 if (const MaterializeTemporaryExpr *MTE = 747 dyn_cast<MaterializeTemporaryExpr>(ArgE)) { 748 ArgE = MTE->GetTemporaryExpr(); 749 IsTemporary = true; 750 } 751 752 Optional<SVal> ConstantVal = svalBuilder.getConstantVal(ArgE); 753 if (!ConstantVal) 754 ConstantVal = UnknownVal(); 755 756 for (ExplodedNodeSet::iterator I = PreVisit.begin(), E = PreVisit.end(); 757 I != E; ++I) { 758 ProgramStateRef State = (*I)->getState(); 759 State = State->BindExpr(DefaultE, LCtx, *ConstantVal); 760 if (IsTemporary) 761 State = createTemporaryRegionIfNeeded(State, LCtx, DefaultE, 762 DefaultE); 763 Bldr2.generateNode(S, *I, State); 764 } 765 766 getCheckerManager().runCheckersForPostStmt(Dst, Tmp, S, *this); 767 Bldr.addNodes(Dst); 768 break; 769 } 770 771 case Expr::ObjCArrayLiteralClass: 772 case Expr::ObjCDictionaryLiteralClass: 773 // FIXME: explicitly model with a region and the actual contents 774 // of the container. For now, conjure a symbol. 775 case Expr::ObjCBoxedExprClass: { 776 Bldr.takeNodes(Pred); 777 778 ExplodedNodeSet preVisit; 779 getCheckerManager().runCheckersForPreStmt(preVisit, Pred, S, *this); 780 781 ExplodedNodeSet Tmp; 782 StmtNodeBuilder Bldr2(preVisit, Tmp, *currBldrCtx); 783 784 const Expr *Ex = cast<Expr>(S); 785 QualType resultType = Ex->getType(); 786 787 for (ExplodedNodeSet::iterator it = preVisit.begin(), et = preVisit.end(); 788 it != et; ++it) { 789 ExplodedNode *N = *it; 790 const LocationContext *LCtx = N->getLocationContext(); 791 SVal result = svalBuilder.conjureSymbolVal(0, Ex, LCtx, resultType, 792 currBldrCtx->blockCount()); 793 ProgramStateRef state = N->getState()->BindExpr(Ex, LCtx, result); 794 Bldr2.generateNode(S, N, state); 795 } 796 797 getCheckerManager().runCheckersForPostStmt(Dst, Tmp, S, *this); 798 Bldr.addNodes(Dst); 799 break; 800 } 801 802 case Stmt::ArraySubscriptExprClass: 803 Bldr.takeNodes(Pred); 804 VisitLvalArraySubscriptExpr(cast<ArraySubscriptExpr>(S), Pred, Dst); 805 Bldr.addNodes(Dst); 806 break; 807 808 case Stmt::GCCAsmStmtClass: 809 Bldr.takeNodes(Pred); 810 VisitGCCAsmStmt(cast<GCCAsmStmt>(S), Pred, Dst); 811 Bldr.addNodes(Dst); 812 break; 813 814 case Stmt::MSAsmStmtClass: 815 Bldr.takeNodes(Pred); 816 VisitMSAsmStmt(cast<MSAsmStmt>(S), Pred, Dst); 817 Bldr.addNodes(Dst); 818 break; 819 820 case Stmt::BlockExprClass: 821 Bldr.takeNodes(Pred); 822 VisitBlockExpr(cast<BlockExpr>(S), Pred, Dst); 823 Bldr.addNodes(Dst); 824 break; 825 826 case Stmt::BinaryOperatorClass: { 827 const BinaryOperator* B = cast<BinaryOperator>(S); 828 if (B->isLogicalOp()) { 829 Bldr.takeNodes(Pred); 830 VisitLogicalExpr(B, Pred, Dst); 831 Bldr.addNodes(Dst); 832 break; 833 } 834 else if (B->getOpcode() == BO_Comma) { 835 ProgramStateRef state = Pred->getState(); 836 Bldr.generateNode(B, Pred, 837 state->BindExpr(B, Pred->getLocationContext(), 838 state->getSVal(B->getRHS(), 839 Pred->getLocationContext()))); 840 break; 841 } 842 843 Bldr.takeNodes(Pred); 844 845 if (AMgr.options.eagerlyAssumeBinOpBifurcation && 846 (B->isRelationalOp() || B->isEqualityOp())) { 847 ExplodedNodeSet Tmp; 848 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Tmp); 849 evalEagerlyAssumeBinOpBifurcation(Dst, Tmp, cast<Expr>(S)); 850 } 851 else 852 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Dst); 853 854 Bldr.addNodes(Dst); 855 break; 856 } 857 858 case Stmt::CXXOperatorCallExprClass: { 859 const CXXOperatorCallExpr *OCE = cast<CXXOperatorCallExpr>(S); 860 861 // For instance method operators, make sure the 'this' argument has a 862 // valid region. 863 const Decl *Callee = OCE->getCalleeDecl(); 864 if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Callee)) { 865 if (MD->isInstance()) { 866 ProgramStateRef State = Pred->getState(); 867 const LocationContext *LCtx = Pred->getLocationContext(); 868 ProgramStateRef NewState = 869 createTemporaryRegionIfNeeded(State, LCtx, OCE->getArg(0)); 870 if (NewState != State) { 871 Pred = Bldr.generateNode(OCE, Pred, NewState, /*Tag=*/0, 872 ProgramPoint::PreStmtKind); 873 // Did we cache out? 874 if (!Pred) 875 break; 876 } 877 } 878 } 879 // FALLTHROUGH 880 } 881 case Stmt::CallExprClass: 882 case Stmt::CXXMemberCallExprClass: 883 case Stmt::UserDefinedLiteralClass: { 884 Bldr.takeNodes(Pred); 885 VisitCallExpr(cast<CallExpr>(S), Pred, Dst); 886 Bldr.addNodes(Dst); 887 break; 888 } 889 890 case Stmt::CXXCatchStmtClass: { 891 Bldr.takeNodes(Pred); 892 VisitCXXCatchStmt(cast<CXXCatchStmt>(S), Pred, Dst); 893 Bldr.addNodes(Dst); 894 break; 895 } 896 897 case Stmt::CXXTemporaryObjectExprClass: 898 case Stmt::CXXConstructExprClass: { 899 Bldr.takeNodes(Pred); 900 VisitCXXConstructExpr(cast<CXXConstructExpr>(S), Pred, Dst); 901 Bldr.addNodes(Dst); 902 break; 903 } 904 905 case Stmt::CXXNewExprClass: { 906 Bldr.takeNodes(Pred); 907 ExplodedNodeSet PostVisit; 908 VisitCXXNewExpr(cast<CXXNewExpr>(S), Pred, PostVisit); 909 getCheckerManager().runCheckersForPostStmt(Dst, PostVisit, S, *this); 910 Bldr.addNodes(Dst); 911 break; 912 } 913 914 case Stmt::CXXDeleteExprClass: { 915 Bldr.takeNodes(Pred); 916 ExplodedNodeSet PreVisit; 917 const CXXDeleteExpr *CDE = cast<CXXDeleteExpr>(S); 918 getCheckerManager().runCheckersForPreStmt(PreVisit, Pred, S, *this); 919 920 for (ExplodedNodeSet::iterator i = PreVisit.begin(), 921 e = PreVisit.end(); i != e ; ++i) 922 VisitCXXDeleteExpr(CDE, *i, Dst); 923 924 Bldr.addNodes(Dst); 925 break; 926 } 927 // FIXME: ChooseExpr is really a constant. We need to fix 928 // the CFG do not model them as explicit control-flow. 929 930 case Stmt::ChooseExprClass: { // __builtin_choose_expr 931 Bldr.takeNodes(Pred); 932 const ChooseExpr *C = cast<ChooseExpr>(S); 933 VisitGuardedExpr(C, C->getLHS(), C->getRHS(), Pred, Dst); 934 Bldr.addNodes(Dst); 935 break; 936 } 937 938 case Stmt::CompoundAssignOperatorClass: 939 Bldr.takeNodes(Pred); 940 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Dst); 941 Bldr.addNodes(Dst); 942 break; 943 944 case Stmt::CompoundLiteralExprClass: 945 Bldr.takeNodes(Pred); 946 VisitCompoundLiteralExpr(cast<CompoundLiteralExpr>(S), Pred, Dst); 947 Bldr.addNodes(Dst); 948 break; 949 950 case Stmt::BinaryConditionalOperatorClass: 951 case Stmt::ConditionalOperatorClass: { // '?' operator 952 Bldr.takeNodes(Pred); 953 const AbstractConditionalOperator *C 954 = cast<AbstractConditionalOperator>(S); 955 VisitGuardedExpr(C, C->getTrueExpr(), C->getFalseExpr(), Pred, Dst); 956 Bldr.addNodes(Dst); 957 break; 958 } 959 960 case Stmt::CXXThisExprClass: 961 Bldr.takeNodes(Pred); 962 VisitCXXThisExpr(cast<CXXThisExpr>(S), Pred, Dst); 963 Bldr.addNodes(Dst); 964 break; 965 966 case Stmt::DeclRefExprClass: { 967 Bldr.takeNodes(Pred); 968 const DeclRefExpr *DE = cast<DeclRefExpr>(S); 969 VisitCommonDeclRefExpr(DE, DE->getDecl(), Pred, Dst); 970 Bldr.addNodes(Dst); 971 break; 972 } 973 974 case Stmt::DeclStmtClass: 975 Bldr.takeNodes(Pred); 976 VisitDeclStmt(cast<DeclStmt>(S), Pred, Dst); 977 Bldr.addNodes(Dst); 978 break; 979 980 case Stmt::ImplicitCastExprClass: 981 case Stmt::CStyleCastExprClass: 982 case Stmt::CXXStaticCastExprClass: 983 case Stmt::CXXDynamicCastExprClass: 984 case Stmt::CXXReinterpretCastExprClass: 985 case Stmt::CXXConstCastExprClass: 986 case Stmt::CXXFunctionalCastExprClass: 987 case Stmt::ObjCBridgedCastExprClass: { 988 Bldr.takeNodes(Pred); 989 const CastExpr *C = cast<CastExpr>(S); 990 // Handle the previsit checks. 991 ExplodedNodeSet dstPrevisit; 992 getCheckerManager().runCheckersForPreStmt(dstPrevisit, Pred, C, *this); 993 994 // Handle the expression itself. 995 ExplodedNodeSet dstExpr; 996 for (ExplodedNodeSet::iterator i = dstPrevisit.begin(), 997 e = dstPrevisit.end(); i != e ; ++i) { 998 VisitCast(C, C->getSubExpr(), *i, dstExpr); 999 } 1000 1001 // Handle the postvisit checks. 1002 getCheckerManager().runCheckersForPostStmt(Dst, dstExpr, C, *this); 1003 Bldr.addNodes(Dst); 1004 break; 1005 } 1006 1007 case Expr::MaterializeTemporaryExprClass: { 1008 Bldr.takeNodes(Pred); 1009 const MaterializeTemporaryExpr *MTE = cast<MaterializeTemporaryExpr>(S); 1010 CreateCXXTemporaryObject(MTE, Pred, Dst); 1011 Bldr.addNodes(Dst); 1012 break; 1013 } 1014 1015 case Stmt::InitListExprClass: 1016 Bldr.takeNodes(Pred); 1017 VisitInitListExpr(cast<InitListExpr>(S), Pred, Dst); 1018 Bldr.addNodes(Dst); 1019 break; 1020 1021 case Stmt::MemberExprClass: 1022 Bldr.takeNodes(Pred); 1023 VisitMemberExpr(cast<MemberExpr>(S), Pred, Dst); 1024 Bldr.addNodes(Dst); 1025 break; 1026 1027 case Stmt::ObjCIvarRefExprClass: 1028 Bldr.takeNodes(Pred); 1029 VisitLvalObjCIvarRefExpr(cast<ObjCIvarRefExpr>(S), Pred, Dst); 1030 Bldr.addNodes(Dst); 1031 break; 1032 1033 case Stmt::ObjCForCollectionStmtClass: 1034 Bldr.takeNodes(Pred); 1035 VisitObjCForCollectionStmt(cast<ObjCForCollectionStmt>(S), Pred, Dst); 1036 Bldr.addNodes(Dst); 1037 break; 1038 1039 case Stmt::ObjCMessageExprClass: 1040 Bldr.takeNodes(Pred); 1041 VisitObjCMessage(cast<ObjCMessageExpr>(S), Pred, Dst); 1042 Bldr.addNodes(Dst); 1043 break; 1044 1045 case Stmt::ObjCAtThrowStmtClass: 1046 case Stmt::CXXThrowExprClass: 1047 // FIXME: This is not complete. We basically treat @throw as 1048 // an abort. 1049 Bldr.generateSink(S, Pred, Pred->getState()); 1050 break; 1051 1052 case Stmt::ReturnStmtClass: 1053 Bldr.takeNodes(Pred); 1054 VisitReturnStmt(cast<ReturnStmt>(S), Pred, Dst); 1055 Bldr.addNodes(Dst); 1056 break; 1057 1058 case Stmt::OffsetOfExprClass: 1059 Bldr.takeNodes(Pred); 1060 VisitOffsetOfExpr(cast<OffsetOfExpr>(S), Pred, Dst); 1061 Bldr.addNodes(Dst); 1062 break; 1063 1064 case Stmt::UnaryExprOrTypeTraitExprClass: 1065 Bldr.takeNodes(Pred); 1066 VisitUnaryExprOrTypeTraitExpr(cast<UnaryExprOrTypeTraitExpr>(S), 1067 Pred, Dst); 1068 Bldr.addNodes(Dst); 1069 break; 1070 1071 case Stmt::StmtExprClass: { 1072 const StmtExpr *SE = cast<StmtExpr>(S); 1073 1074 if (SE->getSubStmt()->body_empty()) { 1075 // Empty statement expression. 1076 assert(SE->getType() == getContext().VoidTy 1077 && "Empty statement expression must have void type."); 1078 break; 1079 } 1080 1081 if (Expr *LastExpr = dyn_cast<Expr>(*SE->getSubStmt()->body_rbegin())) { 1082 ProgramStateRef state = Pred->getState(); 1083 Bldr.generateNode(SE, Pred, 1084 state->BindExpr(SE, Pred->getLocationContext(), 1085 state->getSVal(LastExpr, 1086 Pred->getLocationContext()))); 1087 } 1088 break; 1089 } 1090 1091 case Stmt::UnaryOperatorClass: { 1092 Bldr.takeNodes(Pred); 1093 const UnaryOperator *U = cast<UnaryOperator>(S); 1094 if (AMgr.options.eagerlyAssumeBinOpBifurcation && (U->getOpcode() == UO_LNot)) { 1095 ExplodedNodeSet Tmp; 1096 VisitUnaryOperator(U, Pred, Tmp); 1097 evalEagerlyAssumeBinOpBifurcation(Dst, Tmp, U); 1098 } 1099 else 1100 VisitUnaryOperator(U, Pred, Dst); 1101 Bldr.addNodes(Dst); 1102 break; 1103 } 1104 1105 case Stmt::PseudoObjectExprClass: { 1106 Bldr.takeNodes(Pred); 1107 ProgramStateRef state = Pred->getState(); 1108 const PseudoObjectExpr *PE = cast<PseudoObjectExpr>(S); 1109 if (const Expr *Result = PE->getResultExpr()) { 1110 SVal V = state->getSVal(Result, Pred->getLocationContext()); 1111 Bldr.generateNode(S, Pred, 1112 state->BindExpr(S, Pred->getLocationContext(), V)); 1113 } 1114 else 1115 Bldr.generateNode(S, Pred, 1116 state->BindExpr(S, Pred->getLocationContext(), 1117 UnknownVal())); 1118 1119 Bldr.addNodes(Dst); 1120 break; 1121 } 1122 } 1123} 1124 1125bool ExprEngine::replayWithoutInlining(ExplodedNode *N, 1126 const LocationContext *CalleeLC) { 1127 const StackFrameContext *CalleeSF = CalleeLC->getCurrentStackFrame(); 1128 const StackFrameContext *CallerSF = CalleeSF->getParent()->getCurrentStackFrame(); 1129 assert(CalleeSF && CallerSF); 1130 ExplodedNode *BeforeProcessingCall = 0; 1131 const Stmt *CE = CalleeSF->getCallSite(); 1132 1133 // Find the first node before we started processing the call expression. 1134 while (N) { 1135 ProgramPoint L = N->getLocation(); 1136 BeforeProcessingCall = N; 1137 N = N->pred_empty() ? NULL : *(N->pred_begin()); 1138 1139 // Skip the nodes corresponding to the inlined code. 1140 if (L.getLocationContext()->getCurrentStackFrame() != CallerSF) 1141 continue; 1142 // We reached the caller. Find the node right before we started 1143 // processing the call. 1144 if (L.isPurgeKind()) 1145 continue; 1146 if (L.getAs<PreImplicitCall>()) 1147 continue; 1148 if (L.getAs<CallEnter>()) 1149 continue; 1150 if (Optional<StmtPoint> SP = L.getAs<StmtPoint>()) 1151 if (SP->getStmt() == CE) 1152 continue; 1153 break; 1154 } 1155 1156 if (!BeforeProcessingCall) 1157 return false; 1158 1159 // TODO: Clean up the unneeded nodes. 1160 1161 // Build an Epsilon node from which we will restart the analyzes. 1162 // Note that CE is permitted to be NULL! 1163 ProgramPoint NewNodeLoc = 1164 EpsilonPoint(BeforeProcessingCall->getLocationContext(), CE); 1165 // Add the special flag to GDM to signal retrying with no inlining. 1166 // Note, changing the state ensures that we are not going to cache out. 1167 ProgramStateRef NewNodeState = BeforeProcessingCall->getState(); 1168 NewNodeState = 1169 NewNodeState->set<ReplayWithoutInlining>(const_cast<Stmt *>(CE)); 1170 1171 // Make the new node a successor of BeforeProcessingCall. 1172 bool IsNew = false; 1173 ExplodedNode *NewNode = G.getNode(NewNodeLoc, NewNodeState, false, &IsNew); 1174 // We cached out at this point. Caching out is common due to us backtracking 1175 // from the inlined function, which might spawn several paths. 1176 if (!IsNew) 1177 return true; 1178 1179 NewNode->addPredecessor(BeforeProcessingCall, G); 1180 1181 // Add the new node to the work list. 1182 Engine.enqueueStmtNode(NewNode, CalleeSF->getCallSiteBlock(), 1183 CalleeSF->getIndex()); 1184 NumTimesRetriedWithoutInlining++; 1185 return true; 1186} 1187 1188/// Block entrance. (Update counters). 1189void ExprEngine::processCFGBlockEntrance(const BlockEdge &L, 1190 NodeBuilderWithSinks &nodeBuilder, 1191 ExplodedNode *Pred) { 1192 1193 // FIXME: Refactor this into a checker. 1194 if (nodeBuilder.getContext().blockCount() >= AMgr.options.maxBlockVisitOnPath) { 1195 static SimpleProgramPointTag tag("ExprEngine : Block count exceeded"); 1196 const ExplodedNode *Sink = 1197 nodeBuilder.generateSink(Pred->getState(), Pred, &tag); 1198 1199 // Check if we stopped at the top level function or not. 1200 // Root node should have the location context of the top most function. 1201 const LocationContext *CalleeLC = Pred->getLocation().getLocationContext(); 1202 const LocationContext *CalleeSF = CalleeLC->getCurrentStackFrame(); 1203 const LocationContext *RootLC = 1204 (*G.roots_begin())->getLocation().getLocationContext(); 1205 if (RootLC->getCurrentStackFrame() != CalleeSF) { 1206 Engine.FunctionSummaries->markReachedMaxBlockCount(CalleeSF->getDecl()); 1207 1208 // Re-run the call evaluation without inlining it, by storing the 1209 // no-inlining policy in the state and enqueuing the new work item on 1210 // the list. Replay should almost never fail. Use the stats to catch it 1211 // if it does. 1212 if ((!AMgr.options.NoRetryExhausted && 1213 replayWithoutInlining(Pred, CalleeLC))) 1214 return; 1215 NumMaxBlockCountReachedInInlined++; 1216 } else 1217 NumMaxBlockCountReached++; 1218 1219 // Make sink nodes as exhausted(for stats) only if retry failed. 1220 Engine.blocksExhausted.push_back(std::make_pair(L, Sink)); 1221 } 1222} 1223 1224//===----------------------------------------------------------------------===// 1225// Branch processing. 1226//===----------------------------------------------------------------------===// 1227 1228/// RecoverCastedSymbol - A helper function for ProcessBranch that is used 1229/// to try to recover some path-sensitivity for casts of symbolic 1230/// integers that promote their values (which are currently not tracked well). 1231/// This function returns the SVal bound to Condition->IgnoreCasts if all the 1232// cast(s) did was sign-extend the original value. 1233static SVal RecoverCastedSymbol(ProgramStateManager& StateMgr, 1234 ProgramStateRef state, 1235 const Stmt *Condition, 1236 const LocationContext *LCtx, 1237 ASTContext &Ctx) { 1238 1239 const Expr *Ex = dyn_cast<Expr>(Condition); 1240 if (!Ex) 1241 return UnknownVal(); 1242 1243 uint64_t bits = 0; 1244 bool bitsInit = false; 1245 1246 while (const CastExpr *CE = dyn_cast<CastExpr>(Ex)) { 1247 QualType T = CE->getType(); 1248 1249 if (!T->isIntegralOrEnumerationType()) 1250 return UnknownVal(); 1251 1252 uint64_t newBits = Ctx.getTypeSize(T); 1253 if (!bitsInit || newBits < bits) { 1254 bitsInit = true; 1255 bits = newBits; 1256 } 1257 1258 Ex = CE->getSubExpr(); 1259 } 1260 1261 // We reached a non-cast. Is it a symbolic value? 1262 QualType T = Ex->getType(); 1263 1264 if (!bitsInit || !T->isIntegralOrEnumerationType() || 1265 Ctx.getTypeSize(T) > bits) 1266 return UnknownVal(); 1267 1268 return state->getSVal(Ex, LCtx); 1269} 1270 1271static const Stmt *ResolveCondition(const Stmt *Condition, 1272 const CFGBlock *B) { 1273 if (const Expr *Ex = dyn_cast<Expr>(Condition)) 1274 Condition = Ex->IgnoreParens(); 1275 1276 const BinaryOperator *BO = dyn_cast<BinaryOperator>(Condition); 1277 if (!BO || !BO->isLogicalOp()) 1278 return Condition; 1279 1280 // For logical operations, we still have the case where some branches 1281 // use the traditional "merge" approach and others sink the branch 1282 // directly into the basic blocks representing the logical operation. 1283 // We need to distinguish between those two cases here. 1284 1285 // The invariants are still shifting, but it is possible that the 1286 // last element in a CFGBlock is not a CFGStmt. Look for the last 1287 // CFGStmt as the value of the condition. 1288 CFGBlock::const_reverse_iterator I = B->rbegin(), E = B->rend(); 1289 for (; I != E; ++I) { 1290 CFGElement Elem = *I; 1291 Optional<CFGStmt> CS = Elem.getAs<CFGStmt>(); 1292 if (!CS) 1293 continue; 1294 if (CS->getStmt() != Condition) 1295 break; 1296 return Condition; 1297 } 1298 1299 assert(I != E); 1300 1301 while (Condition) { 1302 BO = dyn_cast<BinaryOperator>(Condition); 1303 if (!BO || !BO->isLogicalOp()) 1304 return Condition; 1305 Condition = BO->getRHS()->IgnoreParens(); 1306 } 1307 llvm_unreachable("could not resolve condition"); 1308} 1309 1310void ExprEngine::processBranch(const Stmt *Condition, const Stmt *Term, 1311 NodeBuilderContext& BldCtx, 1312 ExplodedNode *Pred, 1313 ExplodedNodeSet &Dst, 1314 const CFGBlock *DstT, 1315 const CFGBlock *DstF) { 1316 currBldrCtx = &BldCtx; 1317 1318 // Check for NULL conditions; e.g. "for(;;)" 1319 if (!Condition) { 1320 BranchNodeBuilder NullCondBldr(Pred, Dst, BldCtx, DstT, DstF); 1321 NullCondBldr.markInfeasible(false); 1322 NullCondBldr.generateNode(Pred->getState(), true, Pred); 1323 return; 1324 } 1325 1326 1327 // Resolve the condition in the precense of nested '||' and '&&'. 1328 if (const Expr *Ex = dyn_cast<Expr>(Condition)) 1329 Condition = Ex->IgnoreParens(); 1330 1331 Condition = ResolveCondition(Condition, BldCtx.getBlock()); 1332 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(), 1333 Condition->getLocStart(), 1334 "Error evaluating branch"); 1335 1336 ExplodedNodeSet CheckersOutSet; 1337 getCheckerManager().runCheckersForBranchCondition(Condition, CheckersOutSet, 1338 Pred, *this); 1339 // We generated only sinks. 1340 if (CheckersOutSet.empty()) 1341 return; 1342 1343 BranchNodeBuilder builder(CheckersOutSet, Dst, BldCtx, DstT, DstF); 1344 for (NodeBuilder::iterator I = CheckersOutSet.begin(), 1345 E = CheckersOutSet.end(); E != I; ++I) { 1346 ExplodedNode *PredI = *I; 1347 1348 if (PredI->isSink()) 1349 continue; 1350 1351 ProgramStateRef PrevState = PredI->getState(); 1352 SVal X = PrevState->getSVal(Condition, PredI->getLocationContext()); 1353 1354 if (X.isUnknownOrUndef()) { 1355 // Give it a chance to recover from unknown. 1356 if (const Expr *Ex = dyn_cast<Expr>(Condition)) { 1357 if (Ex->getType()->isIntegralOrEnumerationType()) { 1358 // Try to recover some path-sensitivity. Right now casts of symbolic 1359 // integers that promote their values are currently not tracked well. 1360 // If 'Condition' is such an expression, try and recover the 1361 // underlying value and use that instead. 1362 SVal recovered = RecoverCastedSymbol(getStateManager(), 1363 PrevState, Condition, 1364 PredI->getLocationContext(), 1365 getContext()); 1366 1367 if (!recovered.isUnknown()) { 1368 X = recovered; 1369 } 1370 } 1371 } 1372 } 1373 1374 // If the condition is still unknown, give up. 1375 if (X.isUnknownOrUndef()) { 1376 builder.generateNode(PrevState, true, PredI); 1377 builder.generateNode(PrevState, false, PredI); 1378 continue; 1379 } 1380 1381 DefinedSVal V = X.castAs<DefinedSVal>(); 1382 1383 ProgramStateRef StTrue, StFalse; 1384 tie(StTrue, StFalse) = PrevState->assume(V); 1385 1386 // Process the true branch. 1387 if (builder.isFeasible(true)) { 1388 if (StTrue) 1389 builder.generateNode(StTrue, true, PredI); 1390 else 1391 builder.markInfeasible(true); 1392 } 1393 1394 // Process the false branch. 1395 if (builder.isFeasible(false)) { 1396 if (StFalse) 1397 builder.generateNode(StFalse, false, PredI); 1398 else 1399 builder.markInfeasible(false); 1400 } 1401 } 1402 currBldrCtx = 0; 1403} 1404 1405/// The GDM component containing the set of global variables which have been 1406/// previously initialized with explicit initializers. 1407REGISTER_TRAIT_WITH_PROGRAMSTATE(InitializedGlobalsSet, 1408 llvm::ImmutableSet<const VarDecl *>) 1409 1410void ExprEngine::processStaticInitializer(const DeclStmt *DS, 1411 NodeBuilderContext &BuilderCtx, 1412 ExplodedNode *Pred, 1413 clang::ento::ExplodedNodeSet &Dst, 1414 const CFGBlock *DstT, 1415 const CFGBlock *DstF) { 1416 currBldrCtx = &BuilderCtx; 1417 1418 const VarDecl *VD = cast<VarDecl>(DS->getSingleDecl()); 1419 ProgramStateRef state = Pred->getState(); 1420 bool initHasRun = state->contains<InitializedGlobalsSet>(VD); 1421 BranchNodeBuilder builder(Pred, Dst, BuilderCtx, DstT, DstF); 1422 1423 if (!initHasRun) { 1424 state = state->add<InitializedGlobalsSet>(VD); 1425 } 1426 1427 builder.generateNode(state, initHasRun, Pred); 1428 builder.markInfeasible(!initHasRun); 1429 1430 currBldrCtx = 0; 1431} 1432 1433/// processIndirectGoto - Called by CoreEngine. Used to generate successor 1434/// nodes by processing the 'effects' of a computed goto jump. 1435void ExprEngine::processIndirectGoto(IndirectGotoNodeBuilder &builder) { 1436 1437 ProgramStateRef state = builder.getState(); 1438 SVal V = state->getSVal(builder.getTarget(), builder.getLocationContext()); 1439 1440 // Three possibilities: 1441 // 1442 // (1) We know the computed label. 1443 // (2) The label is NULL (or some other constant), or Undefined. 1444 // (3) We have no clue about the label. Dispatch to all targets. 1445 // 1446 1447 typedef IndirectGotoNodeBuilder::iterator iterator; 1448 1449 if (Optional<loc::GotoLabel> LV = V.getAs<loc::GotoLabel>()) { 1450 const LabelDecl *L = LV->getLabel(); 1451 1452 for (iterator I = builder.begin(), E = builder.end(); I != E; ++I) { 1453 if (I.getLabel() == L) { 1454 builder.generateNode(I, state); 1455 return; 1456 } 1457 } 1458 1459 llvm_unreachable("No block with label."); 1460 } 1461 1462 if (V.getAs<loc::ConcreteInt>() || V.getAs<UndefinedVal>()) { 1463 // Dispatch to the first target and mark it as a sink. 1464 //ExplodedNode* N = builder.generateNode(builder.begin(), state, true); 1465 // FIXME: add checker visit. 1466 // UndefBranches.insert(N); 1467 return; 1468 } 1469 1470 // This is really a catch-all. We don't support symbolics yet. 1471 // FIXME: Implement dispatch for symbolic pointers. 1472 1473 for (iterator I=builder.begin(), E=builder.end(); I != E; ++I) 1474 builder.generateNode(I, state); 1475} 1476 1477/// ProcessEndPath - Called by CoreEngine. Used to generate end-of-path 1478/// nodes when the control reaches the end of a function. 1479void ExprEngine::processEndOfFunction(NodeBuilderContext& BC, 1480 ExplodedNode *Pred) { 1481 StateMgr.EndPath(Pred->getState()); 1482 1483 ExplodedNodeSet Dst; 1484 if (Pred->getLocationContext()->inTopFrame()) { 1485 // Remove dead symbols. 1486 ExplodedNodeSet AfterRemovedDead; 1487 removeDeadOnEndOfFunction(BC, Pred, AfterRemovedDead); 1488 1489 // Notify checkers. 1490 for (ExplodedNodeSet::iterator I = AfterRemovedDead.begin(), 1491 E = AfterRemovedDead.end(); I != E; ++I) { 1492 getCheckerManager().runCheckersForEndFunction(BC, Dst, *I, *this); 1493 } 1494 } else { 1495 getCheckerManager().runCheckersForEndFunction(BC, Dst, Pred, *this); 1496 } 1497 1498 Engine.enqueueEndOfFunction(Dst); 1499} 1500 1501/// ProcessSwitch - Called by CoreEngine. Used to generate successor 1502/// nodes by processing the 'effects' of a switch statement. 1503void ExprEngine::processSwitch(SwitchNodeBuilder& builder) { 1504 typedef SwitchNodeBuilder::iterator iterator; 1505 ProgramStateRef state = builder.getState(); 1506 const Expr *CondE = builder.getCondition(); 1507 SVal CondV_untested = state->getSVal(CondE, builder.getLocationContext()); 1508 1509 if (CondV_untested.isUndef()) { 1510 //ExplodedNode* N = builder.generateDefaultCaseNode(state, true); 1511 // FIXME: add checker 1512 //UndefBranches.insert(N); 1513 1514 return; 1515 } 1516 DefinedOrUnknownSVal CondV = CondV_untested.castAs<DefinedOrUnknownSVal>(); 1517 1518 ProgramStateRef DefaultSt = state; 1519 1520 iterator I = builder.begin(), EI = builder.end(); 1521 bool defaultIsFeasible = I == EI; 1522 1523 for ( ; I != EI; ++I) { 1524 // Successor may be pruned out during CFG construction. 1525 if (!I.getBlock()) 1526 continue; 1527 1528 const CaseStmt *Case = I.getCase(); 1529 1530 // Evaluate the LHS of the case value. 1531 llvm::APSInt V1 = Case->getLHS()->EvaluateKnownConstInt(getContext()); 1532 assert(V1.getBitWidth() == getContext().getTypeSize(CondE->getType())); 1533 1534 // Get the RHS of the case, if it exists. 1535 llvm::APSInt V2; 1536 if (const Expr *E = Case->getRHS()) 1537 V2 = E->EvaluateKnownConstInt(getContext()); 1538 else 1539 V2 = V1; 1540 1541 // FIXME: Eventually we should replace the logic below with a range 1542 // comparison, rather than concretize the values within the range. 1543 // This should be easy once we have "ranges" for NonLVals. 1544 1545 do { 1546 nonloc::ConcreteInt CaseVal(getBasicVals().getValue(V1)); 1547 DefinedOrUnknownSVal Res = svalBuilder.evalEQ(DefaultSt ? DefaultSt : state, 1548 CondV, CaseVal); 1549 1550 // Now "assume" that the case matches. 1551 if (ProgramStateRef stateNew = state->assume(Res, true)) { 1552 builder.generateCaseStmtNode(I, stateNew); 1553 1554 // If CondV evaluates to a constant, then we know that this 1555 // is the *only* case that we can take, so stop evaluating the 1556 // others. 1557 if (CondV.getAs<nonloc::ConcreteInt>()) 1558 return; 1559 } 1560 1561 // Now "assume" that the case doesn't match. Add this state 1562 // to the default state (if it is feasible). 1563 if (DefaultSt) { 1564 if (ProgramStateRef stateNew = DefaultSt->assume(Res, false)) { 1565 defaultIsFeasible = true; 1566 DefaultSt = stateNew; 1567 } 1568 else { 1569 defaultIsFeasible = false; 1570 DefaultSt = NULL; 1571 } 1572 } 1573 1574 // Concretize the next value in the range. 1575 if (V1 == V2) 1576 break; 1577 1578 ++V1; 1579 assert (V1 <= V2); 1580 1581 } while (true); 1582 } 1583 1584 if (!defaultIsFeasible) 1585 return; 1586 1587 // If we have switch(enum value), the default branch is not 1588 // feasible if all of the enum constants not covered by 'case:' statements 1589 // are not feasible values for the switch condition. 1590 // 1591 // Note that this isn't as accurate as it could be. Even if there isn't 1592 // a case for a particular enum value as long as that enum value isn't 1593 // feasible then it shouldn't be considered for making 'default:' reachable. 1594 const SwitchStmt *SS = builder.getSwitch(); 1595 const Expr *CondExpr = SS->getCond()->IgnoreParenImpCasts(); 1596 if (CondExpr->getType()->getAs<EnumType>()) { 1597 if (SS->isAllEnumCasesCovered()) 1598 return; 1599 } 1600 1601 builder.generateDefaultCaseNode(DefaultSt); 1602} 1603 1604//===----------------------------------------------------------------------===// 1605// Transfer functions: Loads and stores. 1606//===----------------------------------------------------------------------===// 1607 1608void ExprEngine::VisitCommonDeclRefExpr(const Expr *Ex, const NamedDecl *D, 1609 ExplodedNode *Pred, 1610 ExplodedNodeSet &Dst) { 1611 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx); 1612 1613 ProgramStateRef state = Pred->getState(); 1614 const LocationContext *LCtx = Pred->getLocationContext(); 1615 1616 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1617 // C permits "extern void v", and if you cast the address to a valid type, 1618 // you can even do things with it. We simply pretend 1619 assert(Ex->isGLValue() || VD->getType()->isVoidType()); 1620 SVal V = state->getLValue(VD, Pred->getLocationContext()); 1621 1622 // For references, the 'lvalue' is the pointer address stored in the 1623 // reference region. 1624 if (VD->getType()->isReferenceType()) { 1625 if (const MemRegion *R = V.getAsRegion()) 1626 V = state->getSVal(R); 1627 else 1628 V = UnknownVal(); 1629 } 1630 1631 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), 0, 1632 ProgramPoint::PostLValueKind); 1633 return; 1634 } 1635 if (const EnumConstantDecl *ED = dyn_cast<EnumConstantDecl>(D)) { 1636 assert(!Ex->isGLValue()); 1637 SVal V = svalBuilder.makeIntVal(ED->getInitVal()); 1638 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V)); 1639 return; 1640 } 1641 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1642 SVal V = svalBuilder.getFunctionPointer(FD); 1643 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), 0, 1644 ProgramPoint::PostLValueKind); 1645 return; 1646 } 1647 if (isa<FieldDecl>(D)) { 1648 // FIXME: Compute lvalue of field pointers-to-member. 1649 // Right now we just use a non-null void pointer, so that it gives proper 1650 // results in boolean contexts. 1651 SVal V = svalBuilder.conjureSymbolVal(Ex, LCtx, getContext().VoidPtrTy, 1652 currBldrCtx->blockCount()); 1653 state = state->assume(V.castAs<DefinedOrUnknownSVal>(), true); 1654 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), 0, 1655 ProgramPoint::PostLValueKind); 1656 return; 1657 } 1658 1659 llvm_unreachable("Support for this Decl not implemented."); 1660} 1661 1662/// VisitArraySubscriptExpr - Transfer function for array accesses 1663void ExprEngine::VisitLvalArraySubscriptExpr(const ArraySubscriptExpr *A, 1664 ExplodedNode *Pred, 1665 ExplodedNodeSet &Dst){ 1666 1667 const Expr *Base = A->getBase()->IgnoreParens(); 1668 const Expr *Idx = A->getIdx()->IgnoreParens(); 1669 1670 1671 ExplodedNodeSet checkerPreStmt; 1672 getCheckerManager().runCheckersForPreStmt(checkerPreStmt, Pred, A, *this); 1673 1674 StmtNodeBuilder Bldr(checkerPreStmt, Dst, *currBldrCtx); 1675 1676 for (ExplodedNodeSet::iterator it = checkerPreStmt.begin(), 1677 ei = checkerPreStmt.end(); it != ei; ++it) { 1678 const LocationContext *LCtx = (*it)->getLocationContext(); 1679 ProgramStateRef state = (*it)->getState(); 1680 SVal V = state->getLValue(A->getType(), 1681 state->getSVal(Idx, LCtx), 1682 state->getSVal(Base, LCtx)); 1683 assert(A->isGLValue()); 1684 Bldr.generateNode(A, *it, state->BindExpr(A, LCtx, V), 0, 1685 ProgramPoint::PostLValueKind); 1686 } 1687} 1688 1689/// VisitMemberExpr - Transfer function for member expressions. 1690void ExprEngine::VisitMemberExpr(const MemberExpr *M, ExplodedNode *Pred, 1691 ExplodedNodeSet &TopDst) { 1692 1693 StmtNodeBuilder Bldr(Pred, TopDst, *currBldrCtx); 1694 ExplodedNodeSet Dst; 1695 ValueDecl *Member = M->getMemberDecl(); 1696 1697 // Handle static member variables and enum constants accessed via 1698 // member syntax. 1699 if (isa<VarDecl>(Member) || isa<EnumConstantDecl>(Member)) { 1700 Bldr.takeNodes(Pred); 1701 VisitCommonDeclRefExpr(M, Member, Pred, Dst); 1702 Bldr.addNodes(Dst); 1703 return; 1704 } 1705 1706 ProgramStateRef state = Pred->getState(); 1707 const LocationContext *LCtx = Pred->getLocationContext(); 1708 Expr *BaseExpr = M->getBase(); 1709 1710 // Handle C++ method calls. 1711 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Member)) { 1712 if (MD->isInstance()) 1713 state = createTemporaryRegionIfNeeded(state, LCtx, BaseExpr); 1714 1715 SVal MDVal = svalBuilder.getFunctionPointer(MD); 1716 state = state->BindExpr(M, LCtx, MDVal); 1717 1718 Bldr.generateNode(M, Pred, state); 1719 return; 1720 } 1721 1722 // Handle regular struct fields / member variables. 1723 state = createTemporaryRegionIfNeeded(state, LCtx, BaseExpr); 1724 SVal baseExprVal = state->getSVal(BaseExpr, LCtx); 1725 1726 FieldDecl *field = cast<FieldDecl>(Member); 1727 SVal L = state->getLValue(field, baseExprVal); 1728 1729 if (M->isGLValue() || M->getType()->isArrayType()) { 1730 1731 // We special case rvalue of array type because the analyzer cannot reason 1732 // about it, since we expect all regions to be wrapped in Locs. So we will 1733 // treat these as lvalues assuming that they will decay to pointers as soon 1734 // as they are used. 1735 if (!M->isGLValue()) { 1736 assert(M->getType()->isArrayType()); 1737 const ImplicitCastExpr *PE = 1738 dyn_cast<ImplicitCastExpr>(Pred->getParentMap().getParent(M)); 1739 if (!PE || PE->getCastKind() != CK_ArrayToPointerDecay) { 1740 assert(false && 1741 "We assume that array is always wrapped in ArrayToPointerDecay"); 1742 L = UnknownVal(); 1743 } 1744 } 1745 1746 if (field->getType()->isReferenceType()) { 1747 if (const MemRegion *R = L.getAsRegion()) 1748 L = state->getSVal(R); 1749 else 1750 L = UnknownVal(); 1751 } 1752 1753 Bldr.generateNode(M, Pred, state->BindExpr(M, LCtx, L), 0, 1754 ProgramPoint::PostLValueKind); 1755 } else { 1756 Bldr.takeNodes(Pred); 1757 evalLoad(Dst, M, M, Pred, state, L); 1758 Bldr.addNodes(Dst); 1759 } 1760} 1761 1762namespace { 1763class CollectReachableSymbolsCallback : public SymbolVisitor { 1764 InvalidatedSymbols Symbols; 1765public: 1766 CollectReachableSymbolsCallback(ProgramStateRef State) {} 1767 const InvalidatedSymbols &getSymbols() const { return Symbols; } 1768 1769 bool VisitSymbol(SymbolRef Sym) { 1770 Symbols.insert(Sym); 1771 return true; 1772 } 1773}; 1774} // end anonymous namespace 1775 1776// A value escapes in three possible cases: 1777// (1) We are binding to something that is not a memory region. 1778// (2) We are binding to a MemrRegion that does not have stack storage. 1779// (3) We are binding to a MemRegion with stack storage that the store 1780// does not understand. 1781ProgramStateRef ExprEngine::processPointerEscapedOnBind(ProgramStateRef State, 1782 SVal Loc, SVal Val) { 1783 // Are we storing to something that causes the value to "escape"? 1784 bool escapes = true; 1785 1786 // TODO: Move to StoreManager. 1787 if (Optional<loc::MemRegionVal> regionLoc = Loc.getAs<loc::MemRegionVal>()) { 1788 escapes = !regionLoc->getRegion()->hasStackStorage(); 1789 1790 if (!escapes) { 1791 // To test (3), generate a new state with the binding added. If it is 1792 // the same state, then it escapes (since the store cannot represent 1793 // the binding). 1794 // Do this only if we know that the store is not supposed to generate the 1795 // same state. 1796 SVal StoredVal = State->getSVal(regionLoc->getRegion()); 1797 if (StoredVal != Val) 1798 escapes = (State == (State->bindLoc(*regionLoc, Val))); 1799 } 1800 } 1801 1802 // If our store can represent the binding and we aren't storing to something 1803 // that doesn't have local storage then just return and have the simulation 1804 // state continue as is. 1805 if (!escapes) 1806 return State; 1807 1808 // Otherwise, find all symbols referenced by 'val' that we are tracking 1809 // and stop tracking them. 1810 CollectReachableSymbolsCallback Scanner = 1811 State->scanReachableSymbols<CollectReachableSymbolsCallback>(Val); 1812 const InvalidatedSymbols &EscapedSymbols = Scanner.getSymbols(); 1813 State = getCheckerManager().runCheckersForPointerEscape(State, 1814 EscapedSymbols, 1815 /*CallEvent*/ 0, 1816 PSK_EscapeOnBind); 1817 1818 return State; 1819} 1820 1821ProgramStateRef 1822ExprEngine::notifyCheckersOfPointerEscape(ProgramStateRef State, 1823 const InvalidatedSymbols *Invalidated, 1824 ArrayRef<const MemRegion *> ExplicitRegions, 1825 ArrayRef<const MemRegion *> Regions, 1826 const CallEvent *Call, 1827 bool IsConst) { 1828 1829 if (!Invalidated || Invalidated->empty()) 1830 return State; 1831 1832 if (!Call) 1833 return getCheckerManager().runCheckersForPointerEscape(State, 1834 *Invalidated, 1835 0, 1836 PSK_EscapeOther, 1837 IsConst); 1838 1839 // Note: Due to current limitations of RegionStore, we only process the top 1840 // level const pointers correctly. The lower level const pointers are 1841 // currently treated as non-const. 1842 if (IsConst) 1843 return getCheckerManager().runCheckersForPointerEscape(State, 1844 *Invalidated, 1845 Call, 1846 PSK_DirectEscapeOnCall, 1847 true); 1848 1849 // If the symbols were invalidated by a call, we want to find out which ones 1850 // were invalidated directly due to being arguments to the call. 1851 InvalidatedSymbols SymbolsDirectlyInvalidated; 1852 for (ArrayRef<const MemRegion *>::iterator I = ExplicitRegions.begin(), 1853 E = ExplicitRegions.end(); I != E; ++I) { 1854 if (const SymbolicRegion *R = (*I)->StripCasts()->getAs<SymbolicRegion>()) 1855 SymbolsDirectlyInvalidated.insert(R->getSymbol()); 1856 } 1857 1858 InvalidatedSymbols SymbolsIndirectlyInvalidated; 1859 for (InvalidatedSymbols::const_iterator I=Invalidated->begin(), 1860 E = Invalidated->end(); I!=E; ++I) { 1861 SymbolRef sym = *I; 1862 if (SymbolsDirectlyInvalidated.count(sym)) 1863 continue; 1864 SymbolsIndirectlyInvalidated.insert(sym); 1865 } 1866 1867 if (!SymbolsDirectlyInvalidated.empty()) 1868 State = getCheckerManager().runCheckersForPointerEscape(State, 1869 SymbolsDirectlyInvalidated, Call, PSK_DirectEscapeOnCall); 1870 1871 // Notify about the symbols that get indirectly invalidated by the call. 1872 if (!SymbolsIndirectlyInvalidated.empty()) 1873 State = getCheckerManager().runCheckersForPointerEscape(State, 1874 SymbolsIndirectlyInvalidated, Call, PSK_IndirectEscapeOnCall); 1875 1876 return State; 1877} 1878 1879/// evalBind - Handle the semantics of binding a value to a specific location. 1880/// This method is used by evalStore and (soon) VisitDeclStmt, and others. 1881void ExprEngine::evalBind(ExplodedNodeSet &Dst, const Stmt *StoreE, 1882 ExplodedNode *Pred, 1883 SVal location, SVal Val, 1884 bool atDeclInit, const ProgramPoint *PP) { 1885 1886 const LocationContext *LC = Pred->getLocationContext(); 1887 PostStmt PS(StoreE, LC); 1888 if (!PP) 1889 PP = &PS; 1890 1891 // Do a previsit of the bind. 1892 ExplodedNodeSet CheckedSet; 1893 getCheckerManager().runCheckersForBind(CheckedSet, Pred, location, Val, 1894 StoreE, *this, *PP); 1895 1896 1897 StmtNodeBuilder Bldr(CheckedSet, Dst, *currBldrCtx); 1898 1899 // If the location is not a 'Loc', it will already be handled by 1900 // the checkers. There is nothing left to do. 1901 if (!location.getAs<Loc>()) { 1902 const ProgramPoint L = PostStore(StoreE, LC, /*Loc*/0, /*tag*/0); 1903 ProgramStateRef state = Pred->getState(); 1904 state = processPointerEscapedOnBind(state, location, Val); 1905 Bldr.generateNode(L, state, Pred); 1906 return; 1907 } 1908 1909 1910 for (ExplodedNodeSet::iterator I = CheckedSet.begin(), E = CheckedSet.end(); 1911 I!=E; ++I) { 1912 ExplodedNode *PredI = *I; 1913 ProgramStateRef state = PredI->getState(); 1914 1915 state = processPointerEscapedOnBind(state, location, Val); 1916 1917 // When binding the value, pass on the hint that this is a initialization. 1918 // For initializations, we do not need to inform clients of region 1919 // changes. 1920 state = state->bindLoc(location.castAs<Loc>(), 1921 Val, /* notifyChanges = */ !atDeclInit); 1922 1923 const MemRegion *LocReg = 0; 1924 if (Optional<loc::MemRegionVal> LocRegVal = 1925 location.getAs<loc::MemRegionVal>()) { 1926 LocReg = LocRegVal->getRegion(); 1927 } 1928 1929 const ProgramPoint L = PostStore(StoreE, LC, LocReg, 0); 1930 Bldr.generateNode(L, state, PredI); 1931 } 1932} 1933 1934/// evalStore - Handle the semantics of a store via an assignment. 1935/// @param Dst The node set to store generated state nodes 1936/// @param AssignE The assignment expression if the store happens in an 1937/// assignment. 1938/// @param LocationE The location expression that is stored to. 1939/// @param state The current simulation state 1940/// @param location The location to store the value 1941/// @param Val The value to be stored 1942void ExprEngine::evalStore(ExplodedNodeSet &Dst, const Expr *AssignE, 1943 const Expr *LocationE, 1944 ExplodedNode *Pred, 1945 ProgramStateRef state, SVal location, SVal Val, 1946 const ProgramPointTag *tag) { 1947 // Proceed with the store. We use AssignE as the anchor for the PostStore 1948 // ProgramPoint if it is non-NULL, and LocationE otherwise. 1949 const Expr *StoreE = AssignE ? AssignE : LocationE; 1950 1951 // Evaluate the location (checks for bad dereferences). 1952 ExplodedNodeSet Tmp; 1953 evalLocation(Tmp, AssignE, LocationE, Pred, state, location, tag, false); 1954 1955 if (Tmp.empty()) 1956 return; 1957 1958 if (location.isUndef()) 1959 return; 1960 1961 for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI) 1962 evalBind(Dst, StoreE, *NI, location, Val, false); 1963} 1964 1965void ExprEngine::evalLoad(ExplodedNodeSet &Dst, 1966 const Expr *NodeEx, 1967 const Expr *BoundEx, 1968 ExplodedNode *Pred, 1969 ProgramStateRef state, 1970 SVal location, 1971 const ProgramPointTag *tag, 1972 QualType LoadTy) 1973{ 1974 assert(!location.getAs<NonLoc>() && "location cannot be a NonLoc."); 1975 1976 // Are we loading from a region? This actually results in two loads; one 1977 // to fetch the address of the referenced value and one to fetch the 1978 // referenced value. 1979 if (const TypedValueRegion *TR = 1980 dyn_cast_or_null<TypedValueRegion>(location.getAsRegion())) { 1981 1982 QualType ValTy = TR->getValueType(); 1983 if (const ReferenceType *RT = ValTy->getAs<ReferenceType>()) { 1984 static SimpleProgramPointTag 1985 loadReferenceTag("ExprEngine : Load Reference"); 1986 ExplodedNodeSet Tmp; 1987 evalLoadCommon(Tmp, NodeEx, BoundEx, Pred, state, 1988 location, &loadReferenceTag, 1989 getContext().getPointerType(RT->getPointeeType())); 1990 1991 // Perform the load from the referenced value. 1992 for (ExplodedNodeSet::iterator I=Tmp.begin(), E=Tmp.end() ; I!=E; ++I) { 1993 state = (*I)->getState(); 1994 location = state->getSVal(BoundEx, (*I)->getLocationContext()); 1995 evalLoadCommon(Dst, NodeEx, BoundEx, *I, state, location, tag, LoadTy); 1996 } 1997 return; 1998 } 1999 } 2000 2001 evalLoadCommon(Dst, NodeEx, BoundEx, Pred, state, location, tag, LoadTy); 2002} 2003 2004void ExprEngine::evalLoadCommon(ExplodedNodeSet &Dst, 2005 const Expr *NodeEx, 2006 const Expr *BoundEx, 2007 ExplodedNode *Pred, 2008 ProgramStateRef state, 2009 SVal location, 2010 const ProgramPointTag *tag, 2011 QualType LoadTy) { 2012 assert(NodeEx); 2013 assert(BoundEx); 2014 // Evaluate the location (checks for bad dereferences). 2015 ExplodedNodeSet Tmp; 2016 evalLocation(Tmp, NodeEx, BoundEx, Pred, state, location, tag, true); 2017 if (Tmp.empty()) 2018 return; 2019 2020 StmtNodeBuilder Bldr(Tmp, Dst, *currBldrCtx); 2021 if (location.isUndef()) 2022 return; 2023 2024 // Proceed with the load. 2025 for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI) { 2026 state = (*NI)->getState(); 2027 const LocationContext *LCtx = (*NI)->getLocationContext(); 2028 2029 SVal V = UnknownVal(); 2030 if (location.isValid()) { 2031 if (LoadTy.isNull()) 2032 LoadTy = BoundEx->getType(); 2033 V = state->getSVal(location.castAs<Loc>(), LoadTy); 2034 } 2035 2036 Bldr.generateNode(NodeEx, *NI, state->BindExpr(BoundEx, LCtx, V), tag, 2037 ProgramPoint::PostLoadKind); 2038 } 2039} 2040 2041void ExprEngine::evalLocation(ExplodedNodeSet &Dst, 2042 const Stmt *NodeEx, 2043 const Stmt *BoundEx, 2044 ExplodedNode *Pred, 2045 ProgramStateRef state, 2046 SVal location, 2047 const ProgramPointTag *tag, 2048 bool isLoad) { 2049 StmtNodeBuilder BldrTop(Pred, Dst, *currBldrCtx); 2050 // Early checks for performance reason. 2051 if (location.isUnknown()) { 2052 return; 2053 } 2054 2055 ExplodedNodeSet Src; 2056 BldrTop.takeNodes(Pred); 2057 StmtNodeBuilder Bldr(Pred, Src, *currBldrCtx); 2058 if (Pred->getState() != state) { 2059 // Associate this new state with an ExplodedNode. 2060 // FIXME: If I pass null tag, the graph is incorrect, e.g for 2061 // int *p; 2062 // p = 0; 2063 // *p = 0xDEADBEEF; 2064 // "p = 0" is not noted as "Null pointer value stored to 'p'" but 2065 // instead "int *p" is noted as 2066 // "Variable 'p' initialized to a null pointer value" 2067 2068 static SimpleProgramPointTag tag("ExprEngine: Location"); 2069 Bldr.generateNode(NodeEx, Pred, state, &tag); 2070 } 2071 ExplodedNodeSet Tmp; 2072 getCheckerManager().runCheckersForLocation(Tmp, Src, location, isLoad, 2073 NodeEx, BoundEx, *this); 2074 BldrTop.addNodes(Tmp); 2075} 2076 2077std::pair<const ProgramPointTag *, const ProgramPointTag*> 2078ExprEngine::geteagerlyAssumeBinOpBifurcationTags() { 2079 static SimpleProgramPointTag 2080 eagerlyAssumeBinOpBifurcationTrue("ExprEngine : Eagerly Assume True"), 2081 eagerlyAssumeBinOpBifurcationFalse("ExprEngine : Eagerly Assume False"); 2082 return std::make_pair(&eagerlyAssumeBinOpBifurcationTrue, 2083 &eagerlyAssumeBinOpBifurcationFalse); 2084} 2085 2086void ExprEngine::evalEagerlyAssumeBinOpBifurcation(ExplodedNodeSet &Dst, 2087 ExplodedNodeSet &Src, 2088 const Expr *Ex) { 2089 StmtNodeBuilder Bldr(Src, Dst, *currBldrCtx); 2090 2091 for (ExplodedNodeSet::iterator I=Src.begin(), E=Src.end(); I!=E; ++I) { 2092 ExplodedNode *Pred = *I; 2093 // Test if the previous node was as the same expression. This can happen 2094 // when the expression fails to evaluate to anything meaningful and 2095 // (as an optimization) we don't generate a node. 2096 ProgramPoint P = Pred->getLocation(); 2097 if (!P.getAs<PostStmt>() || P.castAs<PostStmt>().getStmt() != Ex) { 2098 continue; 2099 } 2100 2101 ProgramStateRef state = Pred->getState(); 2102 SVal V = state->getSVal(Ex, Pred->getLocationContext()); 2103 Optional<nonloc::SymbolVal> SEV = V.getAs<nonloc::SymbolVal>(); 2104 if (SEV && SEV->isExpression()) { 2105 const std::pair<const ProgramPointTag *, const ProgramPointTag*> &tags = 2106 geteagerlyAssumeBinOpBifurcationTags(); 2107 2108 ProgramStateRef StateTrue, StateFalse; 2109 tie(StateTrue, StateFalse) = state->assume(*SEV); 2110 2111 // First assume that the condition is true. 2112 if (StateTrue) { 2113 SVal Val = svalBuilder.makeIntVal(1U, Ex->getType()); 2114 StateTrue = StateTrue->BindExpr(Ex, Pred->getLocationContext(), Val); 2115 Bldr.generateNode(Ex, Pred, StateTrue, tags.first); 2116 } 2117 2118 // Next, assume that the condition is false. 2119 if (StateFalse) { 2120 SVal Val = svalBuilder.makeIntVal(0U, Ex->getType()); 2121 StateFalse = StateFalse->BindExpr(Ex, Pred->getLocationContext(), Val); 2122 Bldr.generateNode(Ex, Pred, StateFalse, tags.second); 2123 } 2124 } 2125 } 2126} 2127 2128void ExprEngine::VisitGCCAsmStmt(const GCCAsmStmt *A, ExplodedNode *Pred, 2129 ExplodedNodeSet &Dst) { 2130 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx); 2131 // We have processed both the inputs and the outputs. All of the outputs 2132 // should evaluate to Locs. Nuke all of their values. 2133 2134 // FIXME: Some day in the future it would be nice to allow a "plug-in" 2135 // which interprets the inline asm and stores proper results in the 2136 // outputs. 2137 2138 ProgramStateRef state = Pred->getState(); 2139 2140 for (GCCAsmStmt::const_outputs_iterator OI = A->begin_outputs(), 2141 OE = A->end_outputs(); OI != OE; ++OI) { 2142 SVal X = state->getSVal(*OI, Pred->getLocationContext()); 2143 assert (!X.getAs<NonLoc>()); // Should be an Lval, or unknown, undef. 2144 2145 if (Optional<Loc> LV = X.getAs<Loc>()) 2146 state = state->bindLoc(*LV, UnknownVal()); 2147 } 2148 2149 Bldr.generateNode(A, Pred, state); 2150} 2151 2152void ExprEngine::VisitMSAsmStmt(const MSAsmStmt *A, ExplodedNode *Pred, 2153 ExplodedNodeSet &Dst) { 2154 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx); 2155 Bldr.generateNode(A, Pred, Pred->getState()); 2156} 2157 2158//===----------------------------------------------------------------------===// 2159// Visualization. 2160//===----------------------------------------------------------------------===// 2161 2162#ifndef NDEBUG 2163static ExprEngine* GraphPrintCheckerState; 2164static SourceManager* GraphPrintSourceManager; 2165 2166namespace llvm { 2167template<> 2168struct DOTGraphTraits<ExplodedNode*> : 2169 public DefaultDOTGraphTraits { 2170 2171 DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {} 2172 2173 // FIXME: Since we do not cache error nodes in ExprEngine now, this does not 2174 // work. 2175 static std::string getNodeAttributes(const ExplodedNode *N, void*) { 2176 2177#if 0 2178 // FIXME: Replace with a general scheme to tell if the node is 2179 // an error node. 2180 if (GraphPrintCheckerState->isImplicitNullDeref(N) || 2181 GraphPrintCheckerState->isExplicitNullDeref(N) || 2182 GraphPrintCheckerState->isUndefDeref(N) || 2183 GraphPrintCheckerState->isUndefStore(N) || 2184 GraphPrintCheckerState->isUndefControlFlow(N) || 2185 GraphPrintCheckerState->isUndefResult(N) || 2186 GraphPrintCheckerState->isBadCall(N) || 2187 GraphPrintCheckerState->isUndefArg(N)) 2188 return "color=\"red\",style=\"filled\""; 2189 2190 if (GraphPrintCheckerState->isNoReturnCall(N)) 2191 return "color=\"blue\",style=\"filled\""; 2192#endif 2193 return ""; 2194 } 2195 2196 static void printLocation(raw_ostream &Out, SourceLocation SLoc) { 2197 if (SLoc.isFileID()) { 2198 Out << "\\lline=" 2199 << GraphPrintSourceManager->getExpansionLineNumber(SLoc) 2200 << " col=" 2201 << GraphPrintSourceManager->getExpansionColumnNumber(SLoc) 2202 << "\\l"; 2203 } 2204 } 2205 2206 static std::string getNodeLabel(const ExplodedNode *N, void*){ 2207 2208 std::string sbuf; 2209 llvm::raw_string_ostream Out(sbuf); 2210 2211 // Program Location. 2212 ProgramPoint Loc = N->getLocation(); 2213 2214 switch (Loc.getKind()) { 2215 case ProgramPoint::BlockEntranceKind: { 2216 Out << "Block Entrance: B" 2217 << Loc.castAs<BlockEntrance>().getBlock()->getBlockID(); 2218 if (const NamedDecl *ND = 2219 dyn_cast<NamedDecl>(Loc.getLocationContext()->getDecl())) { 2220 Out << " ("; 2221 ND->printName(Out); 2222 Out << ")"; 2223 } 2224 break; 2225 } 2226 2227 case ProgramPoint::BlockExitKind: 2228 assert (false); 2229 break; 2230 2231 case ProgramPoint::CallEnterKind: 2232 Out << "CallEnter"; 2233 break; 2234 2235 case ProgramPoint::CallExitBeginKind: 2236 Out << "CallExitBegin"; 2237 break; 2238 2239 case ProgramPoint::CallExitEndKind: 2240 Out << "CallExitEnd"; 2241 break; 2242 2243 case ProgramPoint::PostStmtPurgeDeadSymbolsKind: 2244 Out << "PostStmtPurgeDeadSymbols"; 2245 break; 2246 2247 case ProgramPoint::PreStmtPurgeDeadSymbolsKind: 2248 Out << "PreStmtPurgeDeadSymbols"; 2249 break; 2250 2251 case ProgramPoint::EpsilonKind: 2252 Out << "Epsilon Point"; 2253 break; 2254 2255 case ProgramPoint::PreImplicitCallKind: { 2256 ImplicitCallPoint PC = Loc.castAs<ImplicitCallPoint>(); 2257 Out << "PreCall: "; 2258 2259 // FIXME: Get proper printing options. 2260 PC.getDecl()->print(Out, LangOptions()); 2261 printLocation(Out, PC.getLocation()); 2262 break; 2263 } 2264 2265 case ProgramPoint::PostImplicitCallKind: { 2266 ImplicitCallPoint PC = Loc.castAs<ImplicitCallPoint>(); 2267 Out << "PostCall: "; 2268 2269 // FIXME: Get proper printing options. 2270 PC.getDecl()->print(Out, LangOptions()); 2271 printLocation(Out, PC.getLocation()); 2272 break; 2273 } 2274 2275 case ProgramPoint::PostInitializerKind: { 2276 Out << "PostInitializer: "; 2277 const CXXCtorInitializer *Init = 2278 Loc.castAs<PostInitializer>().getInitializer(); 2279 if (const FieldDecl *FD = Init->getAnyMember()) 2280 Out << *FD; 2281 else { 2282 QualType Ty = Init->getTypeSourceInfo()->getType(); 2283 Ty = Ty.getLocalUnqualifiedType(); 2284 LangOptions LO; // FIXME. 2285 Ty.print(Out, LO); 2286 } 2287 break; 2288 } 2289 2290 case ProgramPoint::BlockEdgeKind: { 2291 const BlockEdge &E = Loc.castAs<BlockEdge>(); 2292 Out << "Edge: (B" << E.getSrc()->getBlockID() << ", B" 2293 << E.getDst()->getBlockID() << ')'; 2294 2295 if (const Stmt *T = E.getSrc()->getTerminator()) { 2296 SourceLocation SLoc = T->getLocStart(); 2297 2298 Out << "\\|Terminator: "; 2299 LangOptions LO; // FIXME. 2300 E.getSrc()->printTerminator(Out, LO); 2301 2302 if (SLoc.isFileID()) { 2303 Out << "\\lline=" 2304 << GraphPrintSourceManager->getExpansionLineNumber(SLoc) 2305 << " col=" 2306 << GraphPrintSourceManager->getExpansionColumnNumber(SLoc); 2307 } 2308 2309 if (isa<SwitchStmt>(T)) { 2310 const Stmt *Label = E.getDst()->getLabel(); 2311 2312 if (Label) { 2313 if (const CaseStmt *C = dyn_cast<CaseStmt>(Label)) { 2314 Out << "\\lcase "; 2315 LangOptions LO; // FIXME. 2316 C->getLHS()->printPretty(Out, 0, PrintingPolicy(LO)); 2317 2318 if (const Stmt *RHS = C->getRHS()) { 2319 Out << " .. "; 2320 RHS->printPretty(Out, 0, PrintingPolicy(LO)); 2321 } 2322 2323 Out << ":"; 2324 } 2325 else { 2326 assert (isa<DefaultStmt>(Label)); 2327 Out << "\\ldefault:"; 2328 } 2329 } 2330 else 2331 Out << "\\l(implicit) default:"; 2332 } 2333 else if (isa<IndirectGotoStmt>(T)) { 2334 // FIXME 2335 } 2336 else { 2337 Out << "\\lCondition: "; 2338 if (*E.getSrc()->succ_begin() == E.getDst()) 2339 Out << "true"; 2340 else 2341 Out << "false"; 2342 } 2343 2344 Out << "\\l"; 2345 } 2346 2347#if 0 2348 // FIXME: Replace with a general scheme to determine 2349 // the name of the check. 2350 if (GraphPrintCheckerState->isUndefControlFlow(N)) { 2351 Out << "\\|Control-flow based on\\lUndefined value.\\l"; 2352 } 2353#endif 2354 break; 2355 } 2356 2357 default: { 2358 const Stmt *S = Loc.castAs<StmtPoint>().getStmt(); 2359 2360 Out << S->getStmtClassName() << ' ' << (const void*) S << ' '; 2361 LangOptions LO; // FIXME. 2362 S->printPretty(Out, 0, PrintingPolicy(LO)); 2363 printLocation(Out, S->getLocStart()); 2364 2365 if (Loc.getAs<PreStmt>()) 2366 Out << "\\lPreStmt\\l;"; 2367 else if (Loc.getAs<PostLoad>()) 2368 Out << "\\lPostLoad\\l;"; 2369 else if (Loc.getAs<PostStore>()) 2370 Out << "\\lPostStore\\l"; 2371 else if (Loc.getAs<PostLValue>()) 2372 Out << "\\lPostLValue\\l"; 2373 2374#if 0 2375 // FIXME: Replace with a general scheme to determine 2376 // the name of the check. 2377 if (GraphPrintCheckerState->isImplicitNullDeref(N)) 2378 Out << "\\|Implicit-Null Dereference.\\l"; 2379 else if (GraphPrintCheckerState->isExplicitNullDeref(N)) 2380 Out << "\\|Explicit-Null Dereference.\\l"; 2381 else if (GraphPrintCheckerState->isUndefDeref(N)) 2382 Out << "\\|Dereference of undefialied value.\\l"; 2383 else if (GraphPrintCheckerState->isUndefStore(N)) 2384 Out << "\\|Store to Undefined Loc."; 2385 else if (GraphPrintCheckerState->isUndefResult(N)) 2386 Out << "\\|Result of operation is undefined."; 2387 else if (GraphPrintCheckerState->isNoReturnCall(N)) 2388 Out << "\\|Call to function marked \"noreturn\"."; 2389 else if (GraphPrintCheckerState->isBadCall(N)) 2390 Out << "\\|Call to NULL/Undefined."; 2391 else if (GraphPrintCheckerState->isUndefArg(N)) 2392 Out << "\\|Argument in call is undefined"; 2393#endif 2394 2395 break; 2396 } 2397 } 2398 2399 ProgramStateRef state = N->getState(); 2400 Out << "\\|StateID: " << (const void*) state.getPtr() 2401 << " NodeID: " << (const void*) N << "\\|"; 2402 state->printDOT(Out); 2403 2404 Out << "\\l"; 2405 2406 if (const ProgramPointTag *tag = Loc.getTag()) { 2407 Out << "\\|Tag: " << tag->getTagDescription(); 2408 Out << "\\l"; 2409 } 2410 return Out.str(); 2411 } 2412}; 2413} // end llvm namespace 2414#endif 2415 2416#ifndef NDEBUG 2417template <typename ITERATOR> 2418ExplodedNode *GetGraphNode(ITERATOR I) { return *I; } 2419 2420template <> ExplodedNode* 2421GetGraphNode<llvm::DenseMap<ExplodedNode*, Expr*>::iterator> 2422 (llvm::DenseMap<ExplodedNode*, Expr*>::iterator I) { 2423 return I->first; 2424} 2425#endif 2426 2427void ExprEngine::ViewGraph(bool trim) { 2428#ifndef NDEBUG 2429 if (trim) { 2430 std::vector<const ExplodedNode*> Src; 2431 2432 // Flush any outstanding reports to make sure we cover all the nodes. 2433 // This does not cause them to get displayed. 2434 for (BugReporter::iterator I=BR.begin(), E=BR.end(); I!=E; ++I) 2435 const_cast<BugType*>(*I)->FlushReports(BR); 2436 2437 // Iterate through the reports and get their nodes. 2438 for (BugReporter::EQClasses_iterator 2439 EI = BR.EQClasses_begin(), EE = BR.EQClasses_end(); EI != EE; ++EI) { 2440 ExplodedNode *N = const_cast<ExplodedNode*>(EI->begin()->getErrorNode()); 2441 if (N) Src.push_back(N); 2442 } 2443 2444 ViewGraph(Src); 2445 } 2446 else { 2447 GraphPrintCheckerState = this; 2448 GraphPrintSourceManager = &getContext().getSourceManager(); 2449 2450 llvm::ViewGraph(*G.roots_begin(), "ExprEngine"); 2451 2452 GraphPrintCheckerState = NULL; 2453 GraphPrintSourceManager = NULL; 2454 } 2455#endif 2456} 2457 2458void ExprEngine::ViewGraph(ArrayRef<const ExplodedNode*> Nodes) { 2459#ifndef NDEBUG 2460 GraphPrintCheckerState = this; 2461 GraphPrintSourceManager = &getContext().getSourceManager(); 2462 2463 OwningPtr<ExplodedGraph> TrimmedG(G.trim(Nodes)); 2464 2465 if (!TrimmedG.get()) 2466 llvm::errs() << "warning: Trimmed ExplodedGraph is empty.\n"; 2467 else 2468 llvm::ViewGraph(*TrimmedG->roots_begin(), "TrimmedExprEngine"); 2469 2470 GraphPrintCheckerState = NULL; 2471 GraphPrintSourceManager = NULL; 2472#endif 2473} 2474