ExprEngine.cpp revision 5955c37230046e8c297f5afb9f91b7c8c1e18446
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 bool IsTemporary = false; 745 if (const MaterializeTemporaryExpr *MTE = 746 dyn_cast<MaterializeTemporaryExpr>(ArgE)) { 747 ArgE = MTE->GetTemporaryExpr(); 748 IsTemporary = true; 749 } 750 751 Optional<SVal> ConstantVal = svalBuilder.getConstantVal(ArgE); 752 if (!ConstantVal) 753 ConstantVal = UnknownVal(); 754 755 for (ExplodedNodeSet::iterator I = PreVisit.begin(), E = PreVisit.end(); 756 I != E; ++I) { 757 ProgramStateRef State = (*I)->getState(); 758 State = State->BindExpr(DefaultE, LCtx, *ConstantVal); 759 if (IsTemporary) 760 State = createTemporaryRegionIfNeeded(State, LCtx, DefaultE, 761 DefaultE); 762 Bldr2.generateNode(S, *I, State); 763 } 764 765 getCheckerManager().runCheckersForPostStmt(Dst, Tmp, S, *this); 766 Bldr.addNodes(Dst); 767 break; 768 } 769 770 case Expr::ObjCArrayLiteralClass: 771 case Expr::ObjCDictionaryLiteralClass: 772 // FIXME: explicitly model with a region and the actual contents 773 // of the container. For now, conjure a symbol. 774 case Expr::ObjCBoxedExprClass: { 775 Bldr.takeNodes(Pred); 776 777 ExplodedNodeSet preVisit; 778 getCheckerManager().runCheckersForPreStmt(preVisit, Pred, S, *this); 779 780 ExplodedNodeSet Tmp; 781 StmtNodeBuilder Bldr2(preVisit, Tmp, *currBldrCtx); 782 783 const Expr *Ex = cast<Expr>(S); 784 QualType resultType = Ex->getType(); 785 786 for (ExplodedNodeSet::iterator it = preVisit.begin(), et = preVisit.end(); 787 it != et; ++it) { 788 ExplodedNode *N = *it; 789 const LocationContext *LCtx = N->getLocationContext(); 790 SVal result = svalBuilder.conjureSymbolVal(0, Ex, LCtx, resultType, 791 currBldrCtx->blockCount()); 792 ProgramStateRef state = N->getState()->BindExpr(Ex, LCtx, result); 793 Bldr2.generateNode(S, N, state); 794 } 795 796 getCheckerManager().runCheckersForPostStmt(Dst, Tmp, S, *this); 797 Bldr.addNodes(Dst); 798 break; 799 } 800 801 case Stmt::ArraySubscriptExprClass: 802 Bldr.takeNodes(Pred); 803 VisitLvalArraySubscriptExpr(cast<ArraySubscriptExpr>(S), Pred, Dst); 804 Bldr.addNodes(Dst); 805 break; 806 807 case Stmt::GCCAsmStmtClass: 808 Bldr.takeNodes(Pred); 809 VisitGCCAsmStmt(cast<GCCAsmStmt>(S), Pred, Dst); 810 Bldr.addNodes(Dst); 811 break; 812 813 case Stmt::MSAsmStmtClass: 814 Bldr.takeNodes(Pred); 815 VisitMSAsmStmt(cast<MSAsmStmt>(S), Pred, Dst); 816 Bldr.addNodes(Dst); 817 break; 818 819 case Stmt::BlockExprClass: 820 Bldr.takeNodes(Pred); 821 VisitBlockExpr(cast<BlockExpr>(S), Pred, Dst); 822 Bldr.addNodes(Dst); 823 break; 824 825 case Stmt::BinaryOperatorClass: { 826 const BinaryOperator* B = cast<BinaryOperator>(S); 827 if (B->isLogicalOp()) { 828 Bldr.takeNodes(Pred); 829 VisitLogicalExpr(B, Pred, Dst); 830 Bldr.addNodes(Dst); 831 break; 832 } 833 else if (B->getOpcode() == BO_Comma) { 834 ProgramStateRef state = Pred->getState(); 835 Bldr.generateNode(B, Pred, 836 state->BindExpr(B, Pred->getLocationContext(), 837 state->getSVal(B->getRHS(), 838 Pred->getLocationContext()))); 839 break; 840 } 841 842 Bldr.takeNodes(Pred); 843 844 if (AMgr.options.eagerlyAssumeBinOpBifurcation && 845 (B->isRelationalOp() || B->isEqualityOp())) { 846 ExplodedNodeSet Tmp; 847 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Tmp); 848 evalEagerlyAssumeBinOpBifurcation(Dst, Tmp, cast<Expr>(S)); 849 } 850 else 851 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Dst); 852 853 Bldr.addNodes(Dst); 854 break; 855 } 856 857 case Stmt::CXXOperatorCallExprClass: { 858 const CXXOperatorCallExpr *OCE = cast<CXXOperatorCallExpr>(S); 859 860 // For instance method operators, make sure the 'this' argument has a 861 // valid region. 862 const Decl *Callee = OCE->getCalleeDecl(); 863 if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Callee)) { 864 if (MD->isInstance()) { 865 ProgramStateRef State = Pred->getState(); 866 const LocationContext *LCtx = Pred->getLocationContext(); 867 ProgramStateRef NewState = 868 createTemporaryRegionIfNeeded(State, LCtx, OCE->getArg(0)); 869 if (NewState != State) { 870 Pred = Bldr.generateNode(OCE, Pred, NewState, /*Tag=*/0, 871 ProgramPoint::PreStmtKind); 872 // Did we cache out? 873 if (!Pred) 874 break; 875 } 876 } 877 } 878 // FALLTHROUGH 879 } 880 case Stmt::CallExprClass: 881 case Stmt::CXXMemberCallExprClass: 882 case Stmt::UserDefinedLiteralClass: { 883 Bldr.takeNodes(Pred); 884 VisitCallExpr(cast<CallExpr>(S), Pred, Dst); 885 Bldr.addNodes(Dst); 886 break; 887 } 888 889 case Stmt::CXXCatchStmtClass: { 890 Bldr.takeNodes(Pred); 891 VisitCXXCatchStmt(cast<CXXCatchStmt>(S), Pred, Dst); 892 Bldr.addNodes(Dst); 893 break; 894 } 895 896 case Stmt::CXXTemporaryObjectExprClass: 897 case Stmt::CXXConstructExprClass: { 898 Bldr.takeNodes(Pred); 899 VisitCXXConstructExpr(cast<CXXConstructExpr>(S), Pred, Dst); 900 Bldr.addNodes(Dst); 901 break; 902 } 903 904 case Stmt::CXXNewExprClass: { 905 Bldr.takeNodes(Pred); 906 ExplodedNodeSet PostVisit; 907 VisitCXXNewExpr(cast<CXXNewExpr>(S), Pred, PostVisit); 908 getCheckerManager().runCheckersForPostStmt(Dst, PostVisit, S, *this); 909 Bldr.addNodes(Dst); 910 break; 911 } 912 913 case Stmt::CXXDeleteExprClass: { 914 Bldr.takeNodes(Pred); 915 ExplodedNodeSet PreVisit; 916 const CXXDeleteExpr *CDE = cast<CXXDeleteExpr>(S); 917 getCheckerManager().runCheckersForPreStmt(PreVisit, Pred, S, *this); 918 919 for (ExplodedNodeSet::iterator i = PreVisit.begin(), 920 e = PreVisit.end(); i != e ; ++i) 921 VisitCXXDeleteExpr(CDE, *i, Dst); 922 923 Bldr.addNodes(Dst); 924 break; 925 } 926 // FIXME: ChooseExpr is really a constant. We need to fix 927 // the CFG do not model them as explicit control-flow. 928 929 case Stmt::ChooseExprClass: { // __builtin_choose_expr 930 Bldr.takeNodes(Pred); 931 const ChooseExpr *C = cast<ChooseExpr>(S); 932 VisitGuardedExpr(C, C->getLHS(), C->getRHS(), Pred, Dst); 933 Bldr.addNodes(Dst); 934 break; 935 } 936 937 case Stmt::CompoundAssignOperatorClass: 938 Bldr.takeNodes(Pred); 939 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Dst); 940 Bldr.addNodes(Dst); 941 break; 942 943 case Stmt::CompoundLiteralExprClass: 944 Bldr.takeNodes(Pred); 945 VisitCompoundLiteralExpr(cast<CompoundLiteralExpr>(S), Pred, Dst); 946 Bldr.addNodes(Dst); 947 break; 948 949 case Stmt::BinaryConditionalOperatorClass: 950 case Stmt::ConditionalOperatorClass: { // '?' operator 951 Bldr.takeNodes(Pred); 952 const AbstractConditionalOperator *C 953 = cast<AbstractConditionalOperator>(S); 954 VisitGuardedExpr(C, C->getTrueExpr(), C->getFalseExpr(), Pred, Dst); 955 Bldr.addNodes(Dst); 956 break; 957 } 958 959 case Stmt::CXXThisExprClass: 960 Bldr.takeNodes(Pred); 961 VisitCXXThisExpr(cast<CXXThisExpr>(S), Pred, Dst); 962 Bldr.addNodes(Dst); 963 break; 964 965 case Stmt::DeclRefExprClass: { 966 Bldr.takeNodes(Pred); 967 const DeclRefExpr *DE = cast<DeclRefExpr>(S); 968 VisitCommonDeclRefExpr(DE, DE->getDecl(), Pred, Dst); 969 Bldr.addNodes(Dst); 970 break; 971 } 972 973 case Stmt::DeclStmtClass: 974 Bldr.takeNodes(Pred); 975 VisitDeclStmt(cast<DeclStmt>(S), Pred, Dst); 976 Bldr.addNodes(Dst); 977 break; 978 979 case Stmt::ImplicitCastExprClass: 980 case Stmt::CStyleCastExprClass: 981 case Stmt::CXXStaticCastExprClass: 982 case Stmt::CXXDynamicCastExprClass: 983 case Stmt::CXXReinterpretCastExprClass: 984 case Stmt::CXXConstCastExprClass: 985 case Stmt::CXXFunctionalCastExprClass: 986 case Stmt::ObjCBridgedCastExprClass: { 987 Bldr.takeNodes(Pred); 988 const CastExpr *C = cast<CastExpr>(S); 989 // Handle the previsit checks. 990 ExplodedNodeSet dstPrevisit; 991 getCheckerManager().runCheckersForPreStmt(dstPrevisit, Pred, C, *this); 992 993 // Handle the expression itself. 994 ExplodedNodeSet dstExpr; 995 for (ExplodedNodeSet::iterator i = dstPrevisit.begin(), 996 e = dstPrevisit.end(); i != e ; ++i) { 997 VisitCast(C, C->getSubExpr(), *i, dstExpr); 998 } 999 1000 // Handle the postvisit checks. 1001 getCheckerManager().runCheckersForPostStmt(Dst, dstExpr, C, *this); 1002 Bldr.addNodes(Dst); 1003 break; 1004 } 1005 1006 case Expr::MaterializeTemporaryExprClass: { 1007 Bldr.takeNodes(Pred); 1008 const MaterializeTemporaryExpr *MTE = cast<MaterializeTemporaryExpr>(S); 1009 CreateCXXTemporaryObject(MTE, Pred, Dst); 1010 Bldr.addNodes(Dst); 1011 break; 1012 } 1013 1014 case Stmt::InitListExprClass: 1015 Bldr.takeNodes(Pred); 1016 VisitInitListExpr(cast<InitListExpr>(S), Pred, Dst); 1017 Bldr.addNodes(Dst); 1018 break; 1019 1020 case Stmt::MemberExprClass: 1021 Bldr.takeNodes(Pred); 1022 VisitMemberExpr(cast<MemberExpr>(S), Pred, Dst); 1023 Bldr.addNodes(Dst); 1024 break; 1025 1026 case Stmt::ObjCIvarRefExprClass: 1027 Bldr.takeNodes(Pred); 1028 VisitLvalObjCIvarRefExpr(cast<ObjCIvarRefExpr>(S), Pred, Dst); 1029 Bldr.addNodes(Dst); 1030 break; 1031 1032 case Stmt::ObjCForCollectionStmtClass: 1033 Bldr.takeNodes(Pred); 1034 VisitObjCForCollectionStmt(cast<ObjCForCollectionStmt>(S), Pred, Dst); 1035 Bldr.addNodes(Dst); 1036 break; 1037 1038 case Stmt::ObjCMessageExprClass: 1039 Bldr.takeNodes(Pred); 1040 VisitObjCMessage(cast<ObjCMessageExpr>(S), Pred, Dst); 1041 Bldr.addNodes(Dst); 1042 break; 1043 1044 case Stmt::ObjCAtThrowStmtClass: 1045 case Stmt::CXXThrowExprClass: 1046 // FIXME: This is not complete. We basically treat @throw as 1047 // an abort. 1048 Bldr.generateSink(S, Pred, Pred->getState()); 1049 break; 1050 1051 case Stmt::ReturnStmtClass: 1052 Bldr.takeNodes(Pred); 1053 VisitReturnStmt(cast<ReturnStmt>(S), Pred, Dst); 1054 Bldr.addNodes(Dst); 1055 break; 1056 1057 case Stmt::OffsetOfExprClass: 1058 Bldr.takeNodes(Pred); 1059 VisitOffsetOfExpr(cast<OffsetOfExpr>(S), Pred, Dst); 1060 Bldr.addNodes(Dst); 1061 break; 1062 1063 case Stmt::UnaryExprOrTypeTraitExprClass: 1064 Bldr.takeNodes(Pred); 1065 VisitUnaryExprOrTypeTraitExpr(cast<UnaryExprOrTypeTraitExpr>(S), 1066 Pred, Dst); 1067 Bldr.addNodes(Dst); 1068 break; 1069 1070 case Stmt::StmtExprClass: { 1071 const StmtExpr *SE = cast<StmtExpr>(S); 1072 1073 if (SE->getSubStmt()->body_empty()) { 1074 // Empty statement expression. 1075 assert(SE->getType() == getContext().VoidTy 1076 && "Empty statement expression must have void type."); 1077 break; 1078 } 1079 1080 if (Expr *LastExpr = dyn_cast<Expr>(*SE->getSubStmt()->body_rbegin())) { 1081 ProgramStateRef state = Pred->getState(); 1082 Bldr.generateNode(SE, Pred, 1083 state->BindExpr(SE, Pred->getLocationContext(), 1084 state->getSVal(LastExpr, 1085 Pred->getLocationContext()))); 1086 } 1087 break; 1088 } 1089 1090 case Stmt::UnaryOperatorClass: { 1091 Bldr.takeNodes(Pred); 1092 const UnaryOperator *U = cast<UnaryOperator>(S); 1093 if (AMgr.options.eagerlyAssumeBinOpBifurcation && (U->getOpcode() == UO_LNot)) { 1094 ExplodedNodeSet Tmp; 1095 VisitUnaryOperator(U, Pred, Tmp); 1096 evalEagerlyAssumeBinOpBifurcation(Dst, Tmp, U); 1097 } 1098 else 1099 VisitUnaryOperator(U, Pred, Dst); 1100 Bldr.addNodes(Dst); 1101 break; 1102 } 1103 1104 case Stmt::PseudoObjectExprClass: { 1105 Bldr.takeNodes(Pred); 1106 ProgramStateRef state = Pred->getState(); 1107 const PseudoObjectExpr *PE = cast<PseudoObjectExpr>(S); 1108 if (const Expr *Result = PE->getResultExpr()) { 1109 SVal V = state->getSVal(Result, Pred->getLocationContext()); 1110 Bldr.generateNode(S, Pred, 1111 state->BindExpr(S, Pred->getLocationContext(), V)); 1112 } 1113 else 1114 Bldr.generateNode(S, Pred, 1115 state->BindExpr(S, Pred->getLocationContext(), 1116 UnknownVal())); 1117 1118 Bldr.addNodes(Dst); 1119 break; 1120 } 1121 } 1122} 1123 1124bool ExprEngine::replayWithoutInlining(ExplodedNode *N, 1125 const LocationContext *CalleeLC) { 1126 const StackFrameContext *CalleeSF = CalleeLC->getCurrentStackFrame(); 1127 const StackFrameContext *CallerSF = CalleeSF->getParent()->getCurrentStackFrame(); 1128 assert(CalleeSF && CallerSF); 1129 ExplodedNode *BeforeProcessingCall = 0; 1130 const Stmt *CE = CalleeSF->getCallSite(); 1131 1132 // Find the first node before we started processing the call expression. 1133 while (N) { 1134 ProgramPoint L = N->getLocation(); 1135 BeforeProcessingCall = N; 1136 N = N->pred_empty() ? NULL : *(N->pred_begin()); 1137 1138 // Skip the nodes corresponding to the inlined code. 1139 if (L.getLocationContext()->getCurrentStackFrame() != CallerSF) 1140 continue; 1141 // We reached the caller. Find the node right before we started 1142 // processing the call. 1143 if (L.isPurgeKind()) 1144 continue; 1145 if (L.getAs<PreImplicitCall>()) 1146 continue; 1147 if (L.getAs<CallEnter>()) 1148 continue; 1149 if (Optional<StmtPoint> SP = L.getAs<StmtPoint>()) 1150 if (SP->getStmt() == CE) 1151 continue; 1152 break; 1153 } 1154 1155 if (!BeforeProcessingCall) 1156 return false; 1157 1158 // TODO: Clean up the unneeded nodes. 1159 1160 // Build an Epsilon node from which we will restart the analyzes. 1161 // Note that CE is permitted to be NULL! 1162 ProgramPoint NewNodeLoc = 1163 EpsilonPoint(BeforeProcessingCall->getLocationContext(), CE); 1164 // Add the special flag to GDM to signal retrying with no inlining. 1165 // Note, changing the state ensures that we are not going to cache out. 1166 ProgramStateRef NewNodeState = BeforeProcessingCall->getState(); 1167 NewNodeState = 1168 NewNodeState->set<ReplayWithoutInlining>(const_cast<Stmt *>(CE)); 1169 1170 // Make the new node a successor of BeforeProcessingCall. 1171 bool IsNew = false; 1172 ExplodedNode *NewNode = G.getNode(NewNodeLoc, NewNodeState, false, &IsNew); 1173 // We cached out at this point. Caching out is common due to us backtracking 1174 // from the inlined function, which might spawn several paths. 1175 if (!IsNew) 1176 return true; 1177 1178 NewNode->addPredecessor(BeforeProcessingCall, G); 1179 1180 // Add the new node to the work list. 1181 Engine.enqueueStmtNode(NewNode, CalleeSF->getCallSiteBlock(), 1182 CalleeSF->getIndex()); 1183 NumTimesRetriedWithoutInlining++; 1184 return true; 1185} 1186 1187/// Block entrance. (Update counters). 1188void ExprEngine::processCFGBlockEntrance(const BlockEdge &L, 1189 NodeBuilderWithSinks &nodeBuilder, 1190 ExplodedNode *Pred) { 1191 1192 // FIXME: Refactor this into a checker. 1193 if (nodeBuilder.getContext().blockCount() >= AMgr.options.maxBlockVisitOnPath) { 1194 static SimpleProgramPointTag tag("ExprEngine : Block count exceeded"); 1195 const ExplodedNode *Sink = 1196 nodeBuilder.generateSink(Pred->getState(), Pred, &tag); 1197 1198 // Check if we stopped at the top level function or not. 1199 // Root node should have the location context of the top most function. 1200 const LocationContext *CalleeLC = Pred->getLocation().getLocationContext(); 1201 const LocationContext *CalleeSF = CalleeLC->getCurrentStackFrame(); 1202 const LocationContext *RootLC = 1203 (*G.roots_begin())->getLocation().getLocationContext(); 1204 if (RootLC->getCurrentStackFrame() != CalleeSF) { 1205 Engine.FunctionSummaries->markReachedMaxBlockCount(CalleeSF->getDecl()); 1206 1207 // Re-run the call evaluation without inlining it, by storing the 1208 // no-inlining policy in the state and enqueuing the new work item on 1209 // the list. Replay should almost never fail. Use the stats to catch it 1210 // if it does. 1211 if ((!AMgr.options.NoRetryExhausted && 1212 replayWithoutInlining(Pred, CalleeLC))) 1213 return; 1214 NumMaxBlockCountReachedInInlined++; 1215 } else 1216 NumMaxBlockCountReached++; 1217 1218 // Make sink nodes as exhausted(for stats) only if retry failed. 1219 Engine.blocksExhausted.push_back(std::make_pair(L, Sink)); 1220 } 1221} 1222 1223//===----------------------------------------------------------------------===// 1224// Branch processing. 1225//===----------------------------------------------------------------------===// 1226 1227/// RecoverCastedSymbol - A helper function for ProcessBranch that is used 1228/// to try to recover some path-sensitivity for casts of symbolic 1229/// integers that promote their values (which are currently not tracked well). 1230/// This function returns the SVal bound to Condition->IgnoreCasts if all the 1231// cast(s) did was sign-extend the original value. 1232static SVal RecoverCastedSymbol(ProgramStateManager& StateMgr, 1233 ProgramStateRef state, 1234 const Stmt *Condition, 1235 const LocationContext *LCtx, 1236 ASTContext &Ctx) { 1237 1238 const Expr *Ex = dyn_cast<Expr>(Condition); 1239 if (!Ex) 1240 return UnknownVal(); 1241 1242 uint64_t bits = 0; 1243 bool bitsInit = false; 1244 1245 while (const CastExpr *CE = dyn_cast<CastExpr>(Ex)) { 1246 QualType T = CE->getType(); 1247 1248 if (!T->isIntegralOrEnumerationType()) 1249 return UnknownVal(); 1250 1251 uint64_t newBits = Ctx.getTypeSize(T); 1252 if (!bitsInit || newBits < bits) { 1253 bitsInit = true; 1254 bits = newBits; 1255 } 1256 1257 Ex = CE->getSubExpr(); 1258 } 1259 1260 // We reached a non-cast. Is it a symbolic value? 1261 QualType T = Ex->getType(); 1262 1263 if (!bitsInit || !T->isIntegralOrEnumerationType() || 1264 Ctx.getTypeSize(T) > bits) 1265 return UnknownVal(); 1266 1267 return state->getSVal(Ex, LCtx); 1268} 1269 1270static const Stmt *ResolveCondition(const Stmt *Condition, 1271 const CFGBlock *B) { 1272 if (const Expr *Ex = dyn_cast<Expr>(Condition)) 1273 Condition = Ex->IgnoreParens(); 1274 1275 const BinaryOperator *BO = dyn_cast<BinaryOperator>(Condition); 1276 if (!BO || !BO->isLogicalOp()) 1277 return Condition; 1278 1279 // For logical operations, we still have the case where some branches 1280 // use the traditional "merge" approach and others sink the branch 1281 // directly into the basic blocks representing the logical operation. 1282 // We need to distinguish between those two cases here. 1283 1284 // The invariants are still shifting, but it is possible that the 1285 // last element in a CFGBlock is not a CFGStmt. Look for the last 1286 // CFGStmt as the value of the condition. 1287 CFGBlock::const_reverse_iterator I = B->rbegin(), E = B->rend(); 1288 for (; I != E; ++I) { 1289 CFGElement Elem = *I; 1290 Optional<CFGStmt> CS = Elem.getAs<CFGStmt>(); 1291 if (!CS) 1292 continue; 1293 if (CS->getStmt() != Condition) 1294 break; 1295 return Condition; 1296 } 1297 1298 assert(I != E); 1299 1300 while (Condition) { 1301 BO = dyn_cast<BinaryOperator>(Condition); 1302 if (!BO || !BO->isLogicalOp()) 1303 return Condition; 1304 Condition = BO->getRHS()->IgnoreParens(); 1305 } 1306 llvm_unreachable("could not resolve condition"); 1307} 1308 1309void ExprEngine::processBranch(const Stmt *Condition, const Stmt *Term, 1310 NodeBuilderContext& BldCtx, 1311 ExplodedNode *Pred, 1312 ExplodedNodeSet &Dst, 1313 const CFGBlock *DstT, 1314 const CFGBlock *DstF) { 1315 currBldrCtx = &BldCtx; 1316 1317 // Check for NULL conditions; e.g. "for(;;)" 1318 if (!Condition) { 1319 BranchNodeBuilder NullCondBldr(Pred, Dst, BldCtx, DstT, DstF); 1320 NullCondBldr.markInfeasible(false); 1321 NullCondBldr.generateNode(Pred->getState(), true, Pred); 1322 return; 1323 } 1324 1325 1326 // Resolve the condition in the precense of nested '||' and '&&'. 1327 if (const Expr *Ex = dyn_cast<Expr>(Condition)) 1328 Condition = Ex->IgnoreParens(); 1329 1330 Condition = ResolveCondition(Condition, BldCtx.getBlock()); 1331 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(), 1332 Condition->getLocStart(), 1333 "Error evaluating branch"); 1334 1335 ExplodedNodeSet CheckersOutSet; 1336 getCheckerManager().runCheckersForBranchCondition(Condition, CheckersOutSet, 1337 Pred, *this); 1338 // We generated only sinks. 1339 if (CheckersOutSet.empty()) 1340 return; 1341 1342 BranchNodeBuilder builder(CheckersOutSet, Dst, BldCtx, DstT, DstF); 1343 for (NodeBuilder::iterator I = CheckersOutSet.begin(), 1344 E = CheckersOutSet.end(); E != I; ++I) { 1345 ExplodedNode *PredI = *I; 1346 1347 if (PredI->isSink()) 1348 continue; 1349 1350 ProgramStateRef PrevState = PredI->getState(); 1351 SVal X = PrevState->getSVal(Condition, PredI->getLocationContext()); 1352 1353 if (X.isUnknownOrUndef()) { 1354 // Give it a chance to recover from unknown. 1355 if (const Expr *Ex = dyn_cast<Expr>(Condition)) { 1356 if (Ex->getType()->isIntegralOrEnumerationType()) { 1357 // Try to recover some path-sensitivity. Right now casts of symbolic 1358 // integers that promote their values are currently not tracked well. 1359 // If 'Condition' is such an expression, try and recover the 1360 // underlying value and use that instead. 1361 SVal recovered = RecoverCastedSymbol(getStateManager(), 1362 PrevState, Condition, 1363 PredI->getLocationContext(), 1364 getContext()); 1365 1366 if (!recovered.isUnknown()) { 1367 X = recovered; 1368 } 1369 } 1370 } 1371 } 1372 1373 // If the condition is still unknown, give up. 1374 if (X.isUnknownOrUndef()) { 1375 builder.generateNode(PrevState, true, PredI); 1376 builder.generateNode(PrevState, false, PredI); 1377 continue; 1378 } 1379 1380 DefinedSVal V = X.castAs<DefinedSVal>(); 1381 1382 ProgramStateRef StTrue, StFalse; 1383 tie(StTrue, StFalse) = PrevState->assume(V); 1384 1385 // Process the true branch. 1386 if (builder.isFeasible(true)) { 1387 if (StTrue) 1388 builder.generateNode(StTrue, true, PredI); 1389 else 1390 builder.markInfeasible(true); 1391 } 1392 1393 // Process the false branch. 1394 if (builder.isFeasible(false)) { 1395 if (StFalse) 1396 builder.generateNode(StFalse, false, PredI); 1397 else 1398 builder.markInfeasible(false); 1399 } 1400 } 1401 currBldrCtx = 0; 1402} 1403 1404/// The GDM component containing the set of global variables which have been 1405/// previously initialized with explicit initializers. 1406REGISTER_TRAIT_WITH_PROGRAMSTATE(InitializedGlobalsSet, 1407 llvm::ImmutableSet<const VarDecl *>) 1408 1409void ExprEngine::processStaticInitializer(const DeclStmt *DS, 1410 NodeBuilderContext &BuilderCtx, 1411 ExplodedNode *Pred, 1412 clang::ento::ExplodedNodeSet &Dst, 1413 const CFGBlock *DstT, 1414 const CFGBlock *DstF) { 1415 currBldrCtx = &BuilderCtx; 1416 1417 const VarDecl *VD = cast<VarDecl>(DS->getSingleDecl()); 1418 ProgramStateRef state = Pred->getState(); 1419 bool initHasRun = state->contains<InitializedGlobalsSet>(VD); 1420 BranchNodeBuilder builder(Pred, Dst, BuilderCtx, DstT, DstF); 1421 1422 if (!initHasRun) { 1423 state = state->add<InitializedGlobalsSet>(VD); 1424 } 1425 1426 builder.generateNode(state, initHasRun, Pred); 1427 builder.markInfeasible(!initHasRun); 1428 1429 currBldrCtx = 0; 1430} 1431 1432/// processIndirectGoto - Called by CoreEngine. Used to generate successor 1433/// nodes by processing the 'effects' of a computed goto jump. 1434void ExprEngine::processIndirectGoto(IndirectGotoNodeBuilder &builder) { 1435 1436 ProgramStateRef state = builder.getState(); 1437 SVal V = state->getSVal(builder.getTarget(), builder.getLocationContext()); 1438 1439 // Three possibilities: 1440 // 1441 // (1) We know the computed label. 1442 // (2) The label is NULL (or some other constant), or Undefined. 1443 // (3) We have no clue about the label. Dispatch to all targets. 1444 // 1445 1446 typedef IndirectGotoNodeBuilder::iterator iterator; 1447 1448 if (Optional<loc::GotoLabel> LV = V.getAs<loc::GotoLabel>()) { 1449 const LabelDecl *L = LV->getLabel(); 1450 1451 for (iterator I = builder.begin(), E = builder.end(); I != E; ++I) { 1452 if (I.getLabel() == L) { 1453 builder.generateNode(I, state); 1454 return; 1455 } 1456 } 1457 1458 llvm_unreachable("No block with label."); 1459 } 1460 1461 if (V.getAs<loc::ConcreteInt>() || V.getAs<UndefinedVal>()) { 1462 // Dispatch to the first target and mark it as a sink. 1463 //ExplodedNode* N = builder.generateNode(builder.begin(), state, true); 1464 // FIXME: add checker visit. 1465 // UndefBranches.insert(N); 1466 return; 1467 } 1468 1469 // This is really a catch-all. We don't support symbolics yet. 1470 // FIXME: Implement dispatch for symbolic pointers. 1471 1472 for (iterator I=builder.begin(), E=builder.end(); I != E; ++I) 1473 builder.generateNode(I, state); 1474} 1475 1476/// ProcessEndPath - Called by CoreEngine. Used to generate end-of-path 1477/// nodes when the control reaches the end of a function. 1478void ExprEngine::processEndOfFunction(NodeBuilderContext& BC, 1479 ExplodedNode *Pred) { 1480 StateMgr.EndPath(Pred->getState()); 1481 1482 ExplodedNodeSet Dst; 1483 if (Pred->getLocationContext()->inTopFrame()) { 1484 // Remove dead symbols. 1485 ExplodedNodeSet AfterRemovedDead; 1486 removeDeadOnEndOfFunction(BC, Pred, AfterRemovedDead); 1487 1488 // Notify checkers. 1489 for (ExplodedNodeSet::iterator I = AfterRemovedDead.begin(), 1490 E = AfterRemovedDead.end(); I != E; ++I) { 1491 getCheckerManager().runCheckersForEndFunction(BC, Dst, *I, *this); 1492 } 1493 } else { 1494 getCheckerManager().runCheckersForEndFunction(BC, Dst, Pred, *this); 1495 } 1496 1497 Engine.enqueueEndOfFunction(Dst); 1498} 1499 1500/// ProcessSwitch - Called by CoreEngine. Used to generate successor 1501/// nodes by processing the 'effects' of a switch statement. 1502void ExprEngine::processSwitch(SwitchNodeBuilder& builder) { 1503 typedef SwitchNodeBuilder::iterator iterator; 1504 ProgramStateRef state = builder.getState(); 1505 const Expr *CondE = builder.getCondition(); 1506 SVal CondV_untested = state->getSVal(CondE, builder.getLocationContext()); 1507 1508 if (CondV_untested.isUndef()) { 1509 //ExplodedNode* N = builder.generateDefaultCaseNode(state, true); 1510 // FIXME: add checker 1511 //UndefBranches.insert(N); 1512 1513 return; 1514 } 1515 DefinedOrUnknownSVal CondV = CondV_untested.castAs<DefinedOrUnknownSVal>(); 1516 1517 ProgramStateRef DefaultSt = state; 1518 1519 iterator I = builder.begin(), EI = builder.end(); 1520 bool defaultIsFeasible = I == EI; 1521 1522 for ( ; I != EI; ++I) { 1523 // Successor may be pruned out during CFG construction. 1524 if (!I.getBlock()) 1525 continue; 1526 1527 const CaseStmt *Case = I.getCase(); 1528 1529 // Evaluate the LHS of the case value. 1530 llvm::APSInt V1 = Case->getLHS()->EvaluateKnownConstInt(getContext()); 1531 assert(V1.getBitWidth() == getContext().getTypeSize(CondE->getType())); 1532 1533 // Get the RHS of the case, if it exists. 1534 llvm::APSInt V2; 1535 if (const Expr *E = Case->getRHS()) 1536 V2 = E->EvaluateKnownConstInt(getContext()); 1537 else 1538 V2 = V1; 1539 1540 // FIXME: Eventually we should replace the logic below with a range 1541 // comparison, rather than concretize the values within the range. 1542 // This should be easy once we have "ranges" for NonLVals. 1543 1544 do { 1545 nonloc::ConcreteInt CaseVal(getBasicVals().getValue(V1)); 1546 DefinedOrUnknownSVal Res = svalBuilder.evalEQ(DefaultSt ? DefaultSt : state, 1547 CondV, CaseVal); 1548 1549 // Now "assume" that the case matches. 1550 if (ProgramStateRef stateNew = state->assume(Res, true)) { 1551 builder.generateCaseStmtNode(I, stateNew); 1552 1553 // If CondV evaluates to a constant, then we know that this 1554 // is the *only* case that we can take, so stop evaluating the 1555 // others. 1556 if (CondV.getAs<nonloc::ConcreteInt>()) 1557 return; 1558 } 1559 1560 // Now "assume" that the case doesn't match. Add this state 1561 // to the default state (if it is feasible). 1562 if (DefaultSt) { 1563 if (ProgramStateRef stateNew = DefaultSt->assume(Res, false)) { 1564 defaultIsFeasible = true; 1565 DefaultSt = stateNew; 1566 } 1567 else { 1568 defaultIsFeasible = false; 1569 DefaultSt = NULL; 1570 } 1571 } 1572 1573 // Concretize the next value in the range. 1574 if (V1 == V2) 1575 break; 1576 1577 ++V1; 1578 assert (V1 <= V2); 1579 1580 } while (true); 1581 } 1582 1583 if (!defaultIsFeasible) 1584 return; 1585 1586 // If we have switch(enum value), the default branch is not 1587 // feasible if all of the enum constants not covered by 'case:' statements 1588 // are not feasible values for the switch condition. 1589 // 1590 // Note that this isn't as accurate as it could be. Even if there isn't 1591 // a case for a particular enum value as long as that enum value isn't 1592 // feasible then it shouldn't be considered for making 'default:' reachable. 1593 const SwitchStmt *SS = builder.getSwitch(); 1594 const Expr *CondExpr = SS->getCond()->IgnoreParenImpCasts(); 1595 if (CondExpr->getType()->getAs<EnumType>()) { 1596 if (SS->isAllEnumCasesCovered()) 1597 return; 1598 } 1599 1600 builder.generateDefaultCaseNode(DefaultSt); 1601} 1602 1603//===----------------------------------------------------------------------===// 1604// Transfer functions: Loads and stores. 1605//===----------------------------------------------------------------------===// 1606 1607void ExprEngine::VisitCommonDeclRefExpr(const Expr *Ex, const NamedDecl *D, 1608 ExplodedNode *Pred, 1609 ExplodedNodeSet &Dst) { 1610 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx); 1611 1612 ProgramStateRef state = Pred->getState(); 1613 const LocationContext *LCtx = Pred->getLocationContext(); 1614 1615 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1616 // C permits "extern void v", and if you cast the address to a valid type, 1617 // you can even do things with it. We simply pretend 1618 assert(Ex->isGLValue() || VD->getType()->isVoidType()); 1619 SVal V = state->getLValue(VD, Pred->getLocationContext()); 1620 1621 // For references, the 'lvalue' is the pointer address stored in the 1622 // reference region. 1623 if (VD->getType()->isReferenceType()) { 1624 if (const MemRegion *R = V.getAsRegion()) 1625 V = state->getSVal(R); 1626 else 1627 V = UnknownVal(); 1628 } 1629 1630 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), 0, 1631 ProgramPoint::PostLValueKind); 1632 return; 1633 } 1634 if (const EnumConstantDecl *ED = dyn_cast<EnumConstantDecl>(D)) { 1635 assert(!Ex->isGLValue()); 1636 SVal V = svalBuilder.makeIntVal(ED->getInitVal()); 1637 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V)); 1638 return; 1639 } 1640 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1641 SVal V = svalBuilder.getFunctionPointer(FD); 1642 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), 0, 1643 ProgramPoint::PostLValueKind); 1644 return; 1645 } 1646 if (isa<FieldDecl>(D)) { 1647 // FIXME: Compute lvalue of field pointers-to-member. 1648 // Right now we just use a non-null void pointer, so that it gives proper 1649 // results in boolean contexts. 1650 SVal V = svalBuilder.conjureSymbolVal(Ex, LCtx, getContext().VoidPtrTy, 1651 currBldrCtx->blockCount()); 1652 state = state->assume(V.castAs<DefinedOrUnknownSVal>(), true); 1653 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), 0, 1654 ProgramPoint::PostLValueKind); 1655 return; 1656 } 1657 1658 llvm_unreachable("Support for this Decl not implemented."); 1659} 1660 1661/// VisitArraySubscriptExpr - Transfer function for array accesses 1662void ExprEngine::VisitLvalArraySubscriptExpr(const ArraySubscriptExpr *A, 1663 ExplodedNode *Pred, 1664 ExplodedNodeSet &Dst){ 1665 1666 const Expr *Base = A->getBase()->IgnoreParens(); 1667 const Expr *Idx = A->getIdx()->IgnoreParens(); 1668 1669 1670 ExplodedNodeSet checkerPreStmt; 1671 getCheckerManager().runCheckersForPreStmt(checkerPreStmt, Pred, A, *this); 1672 1673 StmtNodeBuilder Bldr(checkerPreStmt, Dst, *currBldrCtx); 1674 1675 for (ExplodedNodeSet::iterator it = checkerPreStmt.begin(), 1676 ei = checkerPreStmt.end(); it != ei; ++it) { 1677 const LocationContext *LCtx = (*it)->getLocationContext(); 1678 ProgramStateRef state = (*it)->getState(); 1679 SVal V = state->getLValue(A->getType(), 1680 state->getSVal(Idx, LCtx), 1681 state->getSVal(Base, LCtx)); 1682 assert(A->isGLValue()); 1683 Bldr.generateNode(A, *it, state->BindExpr(A, LCtx, V), 0, 1684 ProgramPoint::PostLValueKind); 1685 } 1686} 1687 1688/// VisitMemberExpr - Transfer function for member expressions. 1689void ExprEngine::VisitMemberExpr(const MemberExpr *M, ExplodedNode *Pred, 1690 ExplodedNodeSet &TopDst) { 1691 1692 StmtNodeBuilder Bldr(Pred, TopDst, *currBldrCtx); 1693 ExplodedNodeSet Dst; 1694 ValueDecl *Member = M->getMemberDecl(); 1695 1696 // Handle static member variables and enum constants accessed via 1697 // member syntax. 1698 if (isa<VarDecl>(Member) || isa<EnumConstantDecl>(Member)) { 1699 Bldr.takeNodes(Pred); 1700 VisitCommonDeclRefExpr(M, Member, Pred, Dst); 1701 Bldr.addNodes(Dst); 1702 return; 1703 } 1704 1705 ProgramStateRef state = Pred->getState(); 1706 const LocationContext *LCtx = Pred->getLocationContext(); 1707 Expr *BaseExpr = M->getBase(); 1708 1709 // Handle C++ method calls. 1710 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Member)) { 1711 if (MD->isInstance()) 1712 state = createTemporaryRegionIfNeeded(state, LCtx, BaseExpr); 1713 1714 SVal MDVal = svalBuilder.getFunctionPointer(MD); 1715 state = state->BindExpr(M, LCtx, MDVal); 1716 1717 Bldr.generateNode(M, Pred, state); 1718 return; 1719 } 1720 1721 // Handle regular struct fields / member variables. 1722 state = createTemporaryRegionIfNeeded(state, LCtx, BaseExpr); 1723 SVal baseExprVal = state->getSVal(BaseExpr, LCtx); 1724 1725 FieldDecl *field = cast<FieldDecl>(Member); 1726 SVal L = state->getLValue(field, baseExprVal); 1727 1728 if (M->isGLValue() || M->getType()->isArrayType()) { 1729 1730 // We special case rvalue of array type because the analyzer cannot reason 1731 // about it, since we expect all regions to be wrapped in Locs. So we will 1732 // treat these as lvalues assuming that they will decay to pointers as soon 1733 // as they are used. 1734 if (!M->isGLValue()) { 1735 assert(M->getType()->isArrayType()); 1736 const ImplicitCastExpr *PE = 1737 dyn_cast<ImplicitCastExpr>(Pred->getParentMap().getParent(M)); 1738 if (!PE || PE->getCastKind() != CK_ArrayToPointerDecay) { 1739 assert(false && 1740 "We assume that array is always wrapped in ArrayToPointerDecay"); 1741 L = UnknownVal(); 1742 } 1743 } 1744 1745 if (field->getType()->isReferenceType()) { 1746 if (const MemRegion *R = L.getAsRegion()) 1747 L = state->getSVal(R); 1748 else 1749 L = UnknownVal(); 1750 } 1751 1752 Bldr.generateNode(M, Pred, state->BindExpr(M, LCtx, L), 0, 1753 ProgramPoint::PostLValueKind); 1754 } else { 1755 Bldr.takeNodes(Pred); 1756 evalLoad(Dst, M, M, Pred, state, L); 1757 Bldr.addNodes(Dst); 1758 } 1759} 1760 1761namespace { 1762class CollectReachableSymbolsCallback : public SymbolVisitor { 1763 InvalidatedSymbols Symbols; 1764public: 1765 CollectReachableSymbolsCallback(ProgramStateRef State) {} 1766 const InvalidatedSymbols &getSymbols() const { return Symbols; } 1767 1768 bool VisitSymbol(SymbolRef Sym) { 1769 Symbols.insert(Sym); 1770 return true; 1771 } 1772}; 1773} // end anonymous namespace 1774 1775// A value escapes in three possible cases: 1776// (1) We are binding to something that is not a memory region. 1777// (2) We are binding to a MemrRegion that does not have stack storage. 1778// (3) We are binding to a MemRegion with stack storage that the store 1779// does not understand. 1780ProgramStateRef ExprEngine::processPointerEscapedOnBind(ProgramStateRef State, 1781 SVal Loc, SVal Val) { 1782 // Are we storing to something that causes the value to "escape"? 1783 bool escapes = true; 1784 1785 // TODO: Move to StoreManager. 1786 if (Optional<loc::MemRegionVal> regionLoc = Loc.getAs<loc::MemRegionVal>()) { 1787 escapes = !regionLoc->getRegion()->hasStackStorage(); 1788 1789 if (!escapes) { 1790 // To test (3), generate a new state with the binding added. If it is 1791 // the same state, then it escapes (since the store cannot represent 1792 // the binding). 1793 // Do this only if we know that the store is not supposed to generate the 1794 // same state. 1795 SVal StoredVal = State->getSVal(regionLoc->getRegion()); 1796 if (StoredVal != Val) 1797 escapes = (State == (State->bindLoc(*regionLoc, Val))); 1798 } 1799 } 1800 1801 // If our store can represent the binding and we aren't storing to something 1802 // that doesn't have local storage then just return and have the simulation 1803 // state continue as is. 1804 if (!escapes) 1805 return State; 1806 1807 // Otherwise, find all symbols referenced by 'val' that we are tracking 1808 // and stop tracking them. 1809 CollectReachableSymbolsCallback Scanner = 1810 State->scanReachableSymbols<CollectReachableSymbolsCallback>(Val); 1811 const InvalidatedSymbols &EscapedSymbols = Scanner.getSymbols(); 1812 State = getCheckerManager().runCheckersForPointerEscape(State, 1813 EscapedSymbols, 1814 /*CallEvent*/ 0, 1815 PSK_EscapeOnBind); 1816 1817 return State; 1818} 1819 1820ProgramStateRef 1821ExprEngine::notifyCheckersOfPointerEscape(ProgramStateRef State, 1822 const InvalidatedSymbols *Invalidated, 1823 ArrayRef<const MemRegion *> ExplicitRegions, 1824 ArrayRef<const MemRegion *> Regions, 1825 const CallEvent *Call, 1826 bool IsConst) { 1827 1828 if (!Invalidated || Invalidated->empty()) 1829 return State; 1830 1831 if (!Call) 1832 return getCheckerManager().runCheckersForPointerEscape(State, 1833 *Invalidated, 1834 0, 1835 PSK_EscapeOther, 1836 IsConst); 1837 1838 // Note: Due to current limitations of RegionStore, we only process the top 1839 // level const pointers correctly. The lower level const pointers are 1840 // currently treated as non-const. 1841 if (IsConst) 1842 return getCheckerManager().runCheckersForPointerEscape(State, 1843 *Invalidated, 1844 Call, 1845 PSK_DirectEscapeOnCall, 1846 true); 1847 1848 // If the symbols were invalidated by a call, we want to find out which ones 1849 // were invalidated directly due to being arguments to the call. 1850 InvalidatedSymbols SymbolsDirectlyInvalidated; 1851 for (ArrayRef<const MemRegion *>::iterator I = ExplicitRegions.begin(), 1852 E = ExplicitRegions.end(); I != E; ++I) { 1853 if (const SymbolicRegion *R = (*I)->StripCasts()->getAs<SymbolicRegion>()) 1854 SymbolsDirectlyInvalidated.insert(R->getSymbol()); 1855 } 1856 1857 InvalidatedSymbols SymbolsIndirectlyInvalidated; 1858 for (InvalidatedSymbols::const_iterator I=Invalidated->begin(), 1859 E = Invalidated->end(); I!=E; ++I) { 1860 SymbolRef sym = *I; 1861 if (SymbolsDirectlyInvalidated.count(sym)) 1862 continue; 1863 SymbolsIndirectlyInvalidated.insert(sym); 1864 } 1865 1866 if (!SymbolsDirectlyInvalidated.empty()) 1867 State = getCheckerManager().runCheckersForPointerEscape(State, 1868 SymbolsDirectlyInvalidated, Call, PSK_DirectEscapeOnCall); 1869 1870 // Notify about the symbols that get indirectly invalidated by the call. 1871 if (!SymbolsIndirectlyInvalidated.empty()) 1872 State = getCheckerManager().runCheckersForPointerEscape(State, 1873 SymbolsIndirectlyInvalidated, Call, PSK_IndirectEscapeOnCall); 1874 1875 return State; 1876} 1877 1878/// evalBind - Handle the semantics of binding a value to a specific location. 1879/// This method is used by evalStore and (soon) VisitDeclStmt, and others. 1880void ExprEngine::evalBind(ExplodedNodeSet &Dst, const Stmt *StoreE, 1881 ExplodedNode *Pred, 1882 SVal location, SVal Val, 1883 bool atDeclInit, const ProgramPoint *PP) { 1884 1885 const LocationContext *LC = Pred->getLocationContext(); 1886 PostStmt PS(StoreE, LC); 1887 if (!PP) 1888 PP = &PS; 1889 1890 // Do a previsit of the bind. 1891 ExplodedNodeSet CheckedSet; 1892 getCheckerManager().runCheckersForBind(CheckedSet, Pred, location, Val, 1893 StoreE, *this, *PP); 1894 1895 1896 StmtNodeBuilder Bldr(CheckedSet, Dst, *currBldrCtx); 1897 1898 // If the location is not a 'Loc', it will already be handled by 1899 // the checkers. There is nothing left to do. 1900 if (!location.getAs<Loc>()) { 1901 const ProgramPoint L = PostStore(StoreE, LC, /*Loc*/0, /*tag*/0); 1902 ProgramStateRef state = Pred->getState(); 1903 state = processPointerEscapedOnBind(state, location, Val); 1904 Bldr.generateNode(L, state, Pred); 1905 return; 1906 } 1907 1908 1909 for (ExplodedNodeSet::iterator I = CheckedSet.begin(), E = CheckedSet.end(); 1910 I!=E; ++I) { 1911 ExplodedNode *PredI = *I; 1912 ProgramStateRef state = PredI->getState(); 1913 1914 state = processPointerEscapedOnBind(state, location, Val); 1915 1916 // When binding the value, pass on the hint that this is a initialization. 1917 // For initializations, we do not need to inform clients of region 1918 // changes. 1919 state = state->bindLoc(location.castAs<Loc>(), 1920 Val, /* notifyChanges = */ !atDeclInit); 1921 1922 const MemRegion *LocReg = 0; 1923 if (Optional<loc::MemRegionVal> LocRegVal = 1924 location.getAs<loc::MemRegionVal>()) { 1925 LocReg = LocRegVal->getRegion(); 1926 } 1927 1928 const ProgramPoint L = PostStore(StoreE, LC, LocReg, 0); 1929 Bldr.generateNode(L, state, PredI); 1930 } 1931} 1932 1933/// evalStore - Handle the semantics of a store via an assignment. 1934/// @param Dst The node set to store generated state nodes 1935/// @param AssignE The assignment expression if the store happens in an 1936/// assignment. 1937/// @param LocationE The location expression that is stored to. 1938/// @param state The current simulation state 1939/// @param location The location to store the value 1940/// @param Val The value to be stored 1941void ExprEngine::evalStore(ExplodedNodeSet &Dst, const Expr *AssignE, 1942 const Expr *LocationE, 1943 ExplodedNode *Pred, 1944 ProgramStateRef state, SVal location, SVal Val, 1945 const ProgramPointTag *tag) { 1946 // Proceed with the store. We use AssignE as the anchor for the PostStore 1947 // ProgramPoint if it is non-NULL, and LocationE otherwise. 1948 const Expr *StoreE = AssignE ? AssignE : LocationE; 1949 1950 // Evaluate the location (checks for bad dereferences). 1951 ExplodedNodeSet Tmp; 1952 evalLocation(Tmp, AssignE, LocationE, Pred, state, location, tag, false); 1953 1954 if (Tmp.empty()) 1955 return; 1956 1957 if (location.isUndef()) 1958 return; 1959 1960 for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI) 1961 evalBind(Dst, StoreE, *NI, location, Val, false); 1962} 1963 1964void ExprEngine::evalLoad(ExplodedNodeSet &Dst, 1965 const Expr *NodeEx, 1966 const Expr *BoundEx, 1967 ExplodedNode *Pred, 1968 ProgramStateRef state, 1969 SVal location, 1970 const ProgramPointTag *tag, 1971 QualType LoadTy) 1972{ 1973 assert(!location.getAs<NonLoc>() && "location cannot be a NonLoc."); 1974 1975 // Are we loading from a region? This actually results in two loads; one 1976 // to fetch the address of the referenced value and one to fetch the 1977 // referenced value. 1978 if (const TypedValueRegion *TR = 1979 dyn_cast_or_null<TypedValueRegion>(location.getAsRegion())) { 1980 1981 QualType ValTy = TR->getValueType(); 1982 if (const ReferenceType *RT = ValTy->getAs<ReferenceType>()) { 1983 static SimpleProgramPointTag 1984 loadReferenceTag("ExprEngine : Load Reference"); 1985 ExplodedNodeSet Tmp; 1986 evalLoadCommon(Tmp, NodeEx, BoundEx, Pred, state, 1987 location, &loadReferenceTag, 1988 getContext().getPointerType(RT->getPointeeType())); 1989 1990 // Perform the load from the referenced value. 1991 for (ExplodedNodeSet::iterator I=Tmp.begin(), E=Tmp.end() ; I!=E; ++I) { 1992 state = (*I)->getState(); 1993 location = state->getSVal(BoundEx, (*I)->getLocationContext()); 1994 evalLoadCommon(Dst, NodeEx, BoundEx, *I, state, location, tag, LoadTy); 1995 } 1996 return; 1997 } 1998 } 1999 2000 evalLoadCommon(Dst, NodeEx, BoundEx, Pred, state, location, tag, LoadTy); 2001} 2002 2003void ExprEngine::evalLoadCommon(ExplodedNodeSet &Dst, 2004 const Expr *NodeEx, 2005 const Expr *BoundEx, 2006 ExplodedNode *Pred, 2007 ProgramStateRef state, 2008 SVal location, 2009 const ProgramPointTag *tag, 2010 QualType LoadTy) { 2011 assert(NodeEx); 2012 assert(BoundEx); 2013 // Evaluate the location (checks for bad dereferences). 2014 ExplodedNodeSet Tmp; 2015 evalLocation(Tmp, NodeEx, BoundEx, Pred, state, location, tag, true); 2016 if (Tmp.empty()) 2017 return; 2018 2019 StmtNodeBuilder Bldr(Tmp, Dst, *currBldrCtx); 2020 if (location.isUndef()) 2021 return; 2022 2023 // Proceed with the load. 2024 for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI) { 2025 state = (*NI)->getState(); 2026 const LocationContext *LCtx = (*NI)->getLocationContext(); 2027 2028 SVal V = UnknownVal(); 2029 if (location.isValid()) { 2030 if (LoadTy.isNull()) 2031 LoadTy = BoundEx->getType(); 2032 V = state->getSVal(location.castAs<Loc>(), LoadTy); 2033 } 2034 2035 Bldr.generateNode(NodeEx, *NI, state->BindExpr(BoundEx, LCtx, V), tag, 2036 ProgramPoint::PostLoadKind); 2037 } 2038} 2039 2040void ExprEngine::evalLocation(ExplodedNodeSet &Dst, 2041 const Stmt *NodeEx, 2042 const Stmt *BoundEx, 2043 ExplodedNode *Pred, 2044 ProgramStateRef state, 2045 SVal location, 2046 const ProgramPointTag *tag, 2047 bool isLoad) { 2048 StmtNodeBuilder BldrTop(Pred, Dst, *currBldrCtx); 2049 // Early checks for performance reason. 2050 if (location.isUnknown()) { 2051 return; 2052 } 2053 2054 ExplodedNodeSet Src; 2055 BldrTop.takeNodes(Pred); 2056 StmtNodeBuilder Bldr(Pred, Src, *currBldrCtx); 2057 if (Pred->getState() != state) { 2058 // Associate this new state with an ExplodedNode. 2059 // FIXME: If I pass null tag, the graph is incorrect, e.g for 2060 // int *p; 2061 // p = 0; 2062 // *p = 0xDEADBEEF; 2063 // "p = 0" is not noted as "Null pointer value stored to 'p'" but 2064 // instead "int *p" is noted as 2065 // "Variable 'p' initialized to a null pointer value" 2066 2067 static SimpleProgramPointTag tag("ExprEngine: Location"); 2068 Bldr.generateNode(NodeEx, Pred, state, &tag); 2069 } 2070 ExplodedNodeSet Tmp; 2071 getCheckerManager().runCheckersForLocation(Tmp, Src, location, isLoad, 2072 NodeEx, BoundEx, *this); 2073 BldrTop.addNodes(Tmp); 2074} 2075 2076std::pair<const ProgramPointTag *, const ProgramPointTag*> 2077ExprEngine::geteagerlyAssumeBinOpBifurcationTags() { 2078 static SimpleProgramPointTag 2079 eagerlyAssumeBinOpBifurcationTrue("ExprEngine : Eagerly Assume True"), 2080 eagerlyAssumeBinOpBifurcationFalse("ExprEngine : Eagerly Assume False"); 2081 return std::make_pair(&eagerlyAssumeBinOpBifurcationTrue, 2082 &eagerlyAssumeBinOpBifurcationFalse); 2083} 2084 2085void ExprEngine::evalEagerlyAssumeBinOpBifurcation(ExplodedNodeSet &Dst, 2086 ExplodedNodeSet &Src, 2087 const Expr *Ex) { 2088 StmtNodeBuilder Bldr(Src, Dst, *currBldrCtx); 2089 2090 for (ExplodedNodeSet::iterator I=Src.begin(), E=Src.end(); I!=E; ++I) { 2091 ExplodedNode *Pred = *I; 2092 // Test if the previous node was as the same expression. This can happen 2093 // when the expression fails to evaluate to anything meaningful and 2094 // (as an optimization) we don't generate a node. 2095 ProgramPoint P = Pred->getLocation(); 2096 if (!P.getAs<PostStmt>() || P.castAs<PostStmt>().getStmt() != Ex) { 2097 continue; 2098 } 2099 2100 ProgramStateRef state = Pred->getState(); 2101 SVal V = state->getSVal(Ex, Pred->getLocationContext()); 2102 Optional<nonloc::SymbolVal> SEV = V.getAs<nonloc::SymbolVal>(); 2103 if (SEV && SEV->isExpression()) { 2104 const std::pair<const ProgramPointTag *, const ProgramPointTag*> &tags = 2105 geteagerlyAssumeBinOpBifurcationTags(); 2106 2107 ProgramStateRef StateTrue, StateFalse; 2108 tie(StateTrue, StateFalse) = state->assume(*SEV); 2109 2110 // First assume that the condition is true. 2111 if (StateTrue) { 2112 SVal Val = svalBuilder.makeIntVal(1U, Ex->getType()); 2113 StateTrue = StateTrue->BindExpr(Ex, Pred->getLocationContext(), Val); 2114 Bldr.generateNode(Ex, Pred, StateTrue, tags.first); 2115 } 2116 2117 // Next, assume that the condition is false. 2118 if (StateFalse) { 2119 SVal Val = svalBuilder.makeIntVal(0U, Ex->getType()); 2120 StateFalse = StateFalse->BindExpr(Ex, Pred->getLocationContext(), Val); 2121 Bldr.generateNode(Ex, Pred, StateFalse, tags.second); 2122 } 2123 } 2124 } 2125} 2126 2127void ExprEngine::VisitGCCAsmStmt(const GCCAsmStmt *A, ExplodedNode *Pred, 2128 ExplodedNodeSet &Dst) { 2129 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx); 2130 // We have processed both the inputs and the outputs. All of the outputs 2131 // should evaluate to Locs. Nuke all of their values. 2132 2133 // FIXME: Some day in the future it would be nice to allow a "plug-in" 2134 // which interprets the inline asm and stores proper results in the 2135 // outputs. 2136 2137 ProgramStateRef state = Pred->getState(); 2138 2139 for (GCCAsmStmt::const_outputs_iterator OI = A->begin_outputs(), 2140 OE = A->end_outputs(); OI != OE; ++OI) { 2141 SVal X = state->getSVal(*OI, Pred->getLocationContext()); 2142 assert (!X.getAs<NonLoc>()); // Should be an Lval, or unknown, undef. 2143 2144 if (Optional<Loc> LV = X.getAs<Loc>()) 2145 state = state->bindLoc(*LV, UnknownVal()); 2146 } 2147 2148 Bldr.generateNode(A, Pred, state); 2149} 2150 2151void ExprEngine::VisitMSAsmStmt(const MSAsmStmt *A, ExplodedNode *Pred, 2152 ExplodedNodeSet &Dst) { 2153 StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx); 2154 Bldr.generateNode(A, Pred, Pred->getState()); 2155} 2156 2157//===----------------------------------------------------------------------===// 2158// Visualization. 2159//===----------------------------------------------------------------------===// 2160 2161#ifndef NDEBUG 2162static ExprEngine* GraphPrintCheckerState; 2163static SourceManager* GraphPrintSourceManager; 2164 2165namespace llvm { 2166template<> 2167struct DOTGraphTraits<ExplodedNode*> : 2168 public DefaultDOTGraphTraits { 2169 2170 DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {} 2171 2172 // FIXME: Since we do not cache error nodes in ExprEngine now, this does not 2173 // work. 2174 static std::string getNodeAttributes(const ExplodedNode *N, void*) { 2175 2176#if 0 2177 // FIXME: Replace with a general scheme to tell if the node is 2178 // an error node. 2179 if (GraphPrintCheckerState->isImplicitNullDeref(N) || 2180 GraphPrintCheckerState->isExplicitNullDeref(N) || 2181 GraphPrintCheckerState->isUndefDeref(N) || 2182 GraphPrintCheckerState->isUndefStore(N) || 2183 GraphPrintCheckerState->isUndefControlFlow(N) || 2184 GraphPrintCheckerState->isUndefResult(N) || 2185 GraphPrintCheckerState->isBadCall(N) || 2186 GraphPrintCheckerState->isUndefArg(N)) 2187 return "color=\"red\",style=\"filled\""; 2188 2189 if (GraphPrintCheckerState->isNoReturnCall(N)) 2190 return "color=\"blue\",style=\"filled\""; 2191#endif 2192 return ""; 2193 } 2194 2195 static void printLocation(raw_ostream &Out, SourceLocation SLoc) { 2196 if (SLoc.isFileID()) { 2197 Out << "\\lline=" 2198 << GraphPrintSourceManager->getExpansionLineNumber(SLoc) 2199 << " col=" 2200 << GraphPrintSourceManager->getExpansionColumnNumber(SLoc) 2201 << "\\l"; 2202 } 2203 } 2204 2205 static std::string getNodeLabel(const ExplodedNode *N, void*){ 2206 2207 std::string sbuf; 2208 llvm::raw_string_ostream Out(sbuf); 2209 2210 // Program Location. 2211 ProgramPoint Loc = N->getLocation(); 2212 2213 switch (Loc.getKind()) { 2214 case ProgramPoint::BlockEntranceKind: { 2215 Out << "Block Entrance: B" 2216 << Loc.castAs<BlockEntrance>().getBlock()->getBlockID(); 2217 if (const NamedDecl *ND = 2218 dyn_cast<NamedDecl>(Loc.getLocationContext()->getDecl())) { 2219 Out << " ("; 2220 ND->printName(Out); 2221 Out << ")"; 2222 } 2223 break; 2224 } 2225 2226 case ProgramPoint::BlockExitKind: 2227 assert (false); 2228 break; 2229 2230 case ProgramPoint::CallEnterKind: 2231 Out << "CallEnter"; 2232 break; 2233 2234 case ProgramPoint::CallExitBeginKind: 2235 Out << "CallExitBegin"; 2236 break; 2237 2238 case ProgramPoint::CallExitEndKind: 2239 Out << "CallExitEnd"; 2240 break; 2241 2242 case ProgramPoint::PostStmtPurgeDeadSymbolsKind: 2243 Out << "PostStmtPurgeDeadSymbols"; 2244 break; 2245 2246 case ProgramPoint::PreStmtPurgeDeadSymbolsKind: 2247 Out << "PreStmtPurgeDeadSymbols"; 2248 break; 2249 2250 case ProgramPoint::EpsilonKind: 2251 Out << "Epsilon Point"; 2252 break; 2253 2254 case ProgramPoint::PreImplicitCallKind: { 2255 ImplicitCallPoint PC = Loc.castAs<ImplicitCallPoint>(); 2256 Out << "PreCall: "; 2257 2258 // FIXME: Get proper printing options. 2259 PC.getDecl()->print(Out, LangOptions()); 2260 printLocation(Out, PC.getLocation()); 2261 break; 2262 } 2263 2264 case ProgramPoint::PostImplicitCallKind: { 2265 ImplicitCallPoint PC = Loc.castAs<ImplicitCallPoint>(); 2266 Out << "PostCall: "; 2267 2268 // FIXME: Get proper printing options. 2269 PC.getDecl()->print(Out, LangOptions()); 2270 printLocation(Out, PC.getLocation()); 2271 break; 2272 } 2273 2274 case ProgramPoint::PostInitializerKind: { 2275 Out << "PostInitializer: "; 2276 const CXXCtorInitializer *Init = 2277 Loc.castAs<PostInitializer>().getInitializer(); 2278 if (const FieldDecl *FD = Init->getAnyMember()) 2279 Out << *FD; 2280 else { 2281 QualType Ty = Init->getTypeSourceInfo()->getType(); 2282 Ty = Ty.getLocalUnqualifiedType(); 2283 LangOptions LO; // FIXME. 2284 Ty.print(Out, LO); 2285 } 2286 break; 2287 } 2288 2289 case ProgramPoint::BlockEdgeKind: { 2290 const BlockEdge &E = Loc.castAs<BlockEdge>(); 2291 Out << "Edge: (B" << E.getSrc()->getBlockID() << ", B" 2292 << E.getDst()->getBlockID() << ')'; 2293 2294 if (const Stmt *T = E.getSrc()->getTerminator()) { 2295 SourceLocation SLoc = T->getLocStart(); 2296 2297 Out << "\\|Terminator: "; 2298 LangOptions LO; // FIXME. 2299 E.getSrc()->printTerminator(Out, LO); 2300 2301 if (SLoc.isFileID()) { 2302 Out << "\\lline=" 2303 << GraphPrintSourceManager->getExpansionLineNumber(SLoc) 2304 << " col=" 2305 << GraphPrintSourceManager->getExpansionColumnNumber(SLoc); 2306 } 2307 2308 if (isa<SwitchStmt>(T)) { 2309 const Stmt *Label = E.getDst()->getLabel(); 2310 2311 if (Label) { 2312 if (const CaseStmt *C = dyn_cast<CaseStmt>(Label)) { 2313 Out << "\\lcase "; 2314 LangOptions LO; // FIXME. 2315 C->getLHS()->printPretty(Out, 0, PrintingPolicy(LO)); 2316 2317 if (const Stmt *RHS = C->getRHS()) { 2318 Out << " .. "; 2319 RHS->printPretty(Out, 0, PrintingPolicy(LO)); 2320 } 2321 2322 Out << ":"; 2323 } 2324 else { 2325 assert (isa<DefaultStmt>(Label)); 2326 Out << "\\ldefault:"; 2327 } 2328 } 2329 else 2330 Out << "\\l(implicit) default:"; 2331 } 2332 else if (isa<IndirectGotoStmt>(T)) { 2333 // FIXME 2334 } 2335 else { 2336 Out << "\\lCondition: "; 2337 if (*E.getSrc()->succ_begin() == E.getDst()) 2338 Out << "true"; 2339 else 2340 Out << "false"; 2341 } 2342 2343 Out << "\\l"; 2344 } 2345 2346#if 0 2347 // FIXME: Replace with a general scheme to determine 2348 // the name of the check. 2349 if (GraphPrintCheckerState->isUndefControlFlow(N)) { 2350 Out << "\\|Control-flow based on\\lUndefined value.\\l"; 2351 } 2352#endif 2353 break; 2354 } 2355 2356 default: { 2357 const Stmt *S = Loc.castAs<StmtPoint>().getStmt(); 2358 2359 Out << S->getStmtClassName() << ' ' << (const void*) S << ' '; 2360 LangOptions LO; // FIXME. 2361 S->printPretty(Out, 0, PrintingPolicy(LO)); 2362 printLocation(Out, S->getLocStart()); 2363 2364 if (Loc.getAs<PreStmt>()) 2365 Out << "\\lPreStmt\\l;"; 2366 else if (Loc.getAs<PostLoad>()) 2367 Out << "\\lPostLoad\\l;"; 2368 else if (Loc.getAs<PostStore>()) 2369 Out << "\\lPostStore\\l"; 2370 else if (Loc.getAs<PostLValue>()) 2371 Out << "\\lPostLValue\\l"; 2372 2373#if 0 2374 // FIXME: Replace with a general scheme to determine 2375 // the name of the check. 2376 if (GraphPrintCheckerState->isImplicitNullDeref(N)) 2377 Out << "\\|Implicit-Null Dereference.\\l"; 2378 else if (GraphPrintCheckerState->isExplicitNullDeref(N)) 2379 Out << "\\|Explicit-Null Dereference.\\l"; 2380 else if (GraphPrintCheckerState->isUndefDeref(N)) 2381 Out << "\\|Dereference of undefialied value.\\l"; 2382 else if (GraphPrintCheckerState->isUndefStore(N)) 2383 Out << "\\|Store to Undefined Loc."; 2384 else if (GraphPrintCheckerState->isUndefResult(N)) 2385 Out << "\\|Result of operation is undefined."; 2386 else if (GraphPrintCheckerState->isNoReturnCall(N)) 2387 Out << "\\|Call to function marked \"noreturn\"."; 2388 else if (GraphPrintCheckerState->isBadCall(N)) 2389 Out << "\\|Call to NULL/Undefined."; 2390 else if (GraphPrintCheckerState->isUndefArg(N)) 2391 Out << "\\|Argument in call is undefined"; 2392#endif 2393 2394 break; 2395 } 2396 } 2397 2398 ProgramStateRef state = N->getState(); 2399 Out << "\\|StateID: " << (const void*) state.getPtr() 2400 << " NodeID: " << (const void*) N << "\\|"; 2401 state->printDOT(Out); 2402 2403 Out << "\\l"; 2404 2405 if (const ProgramPointTag *tag = Loc.getTag()) { 2406 Out << "\\|Tag: " << tag->getTagDescription(); 2407 Out << "\\l"; 2408 } 2409 return Out.str(); 2410 } 2411}; 2412} // end llvm namespace 2413#endif 2414 2415#ifndef NDEBUG 2416template <typename ITERATOR> 2417ExplodedNode *GetGraphNode(ITERATOR I) { return *I; } 2418 2419template <> ExplodedNode* 2420GetGraphNode<llvm::DenseMap<ExplodedNode*, Expr*>::iterator> 2421 (llvm::DenseMap<ExplodedNode*, Expr*>::iterator I) { 2422 return I->first; 2423} 2424#endif 2425 2426void ExprEngine::ViewGraph(bool trim) { 2427#ifndef NDEBUG 2428 if (trim) { 2429 std::vector<const ExplodedNode*> Src; 2430 2431 // Flush any outstanding reports to make sure we cover all the nodes. 2432 // This does not cause them to get displayed. 2433 for (BugReporter::iterator I=BR.begin(), E=BR.end(); I!=E; ++I) 2434 const_cast<BugType*>(*I)->FlushReports(BR); 2435 2436 // Iterate through the reports and get their nodes. 2437 for (BugReporter::EQClasses_iterator 2438 EI = BR.EQClasses_begin(), EE = BR.EQClasses_end(); EI != EE; ++EI) { 2439 ExplodedNode *N = const_cast<ExplodedNode*>(EI->begin()->getErrorNode()); 2440 if (N) Src.push_back(N); 2441 } 2442 2443 ViewGraph(Src); 2444 } 2445 else { 2446 GraphPrintCheckerState = this; 2447 GraphPrintSourceManager = &getContext().getSourceManager(); 2448 2449 llvm::ViewGraph(*G.roots_begin(), "ExprEngine"); 2450 2451 GraphPrintCheckerState = NULL; 2452 GraphPrintSourceManager = NULL; 2453 } 2454#endif 2455} 2456 2457void ExprEngine::ViewGraph(ArrayRef<const ExplodedNode*> Nodes) { 2458#ifndef NDEBUG 2459 GraphPrintCheckerState = this; 2460 GraphPrintSourceManager = &getContext().getSourceManager(); 2461 2462 OwningPtr<ExplodedGraph> TrimmedG(G.trim(Nodes)); 2463 2464 if (!TrimmedG.get()) 2465 llvm::errs() << "warning: Trimmed ExplodedGraph is empty.\n"; 2466 else 2467 llvm::ViewGraph(*TrimmedG->roots_begin(), "TrimmedExprEngine"); 2468 2469 GraphPrintCheckerState = NULL; 2470 GraphPrintSourceManager = NULL; 2471#endif 2472} 2473