ExprEngine.cpp revision 66c40400e7d6272b0cd675ada18dd62c1f0362c7
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#include "clang/StaticAnalyzer/Core/CheckerManager.h" 17#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" 18#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h" 19#include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h" 20#include "clang/StaticAnalyzer/Core/PathSensitive/ObjCMessage.h" 21#include "clang/AST/CharUnits.h" 22#include "clang/AST/ParentMap.h" 23#include "clang/AST/StmtObjC.h" 24#include "clang/AST/DeclCXX.h" 25#include "clang/Basic/Builtins.h" 26#include "clang/Basic/SourceManager.h" 27#include "clang/Basic/PrettyStackTrace.h" 28#include "llvm/Support/raw_ostream.h" 29#include "llvm/ADT/ImmutableList.h" 30 31#ifndef NDEBUG 32#include "llvm/Support/GraphWriter.h" 33#endif 34 35using namespace clang; 36using namespace ento; 37using llvm::APSInt; 38 39//===----------------------------------------------------------------------===// 40// Utility functions. 41//===----------------------------------------------------------------------===// 42 43static inline Selector GetNullarySelector(const char* name, ASTContext &Ctx) { 44 IdentifierInfo* II = &Ctx.Idents.get(name); 45 return Ctx.Selectors.getSelector(0, &II); 46} 47 48//===----------------------------------------------------------------------===// 49// Engine construction and deletion. 50//===----------------------------------------------------------------------===// 51 52ExprEngine::ExprEngine(AnalysisManager &mgr, bool gcEnabled) 53 : AMgr(mgr), 54 AnalysisDeclContexts(mgr.getAnalysisDeclContextManager()), 55 Engine(*this), 56 G(Engine.getGraph()), 57 StateMgr(getContext(), mgr.getStoreManagerCreator(), 58 mgr.getConstraintManagerCreator(), G.getAllocator(), 59 *this), 60 SymMgr(StateMgr.getSymbolManager()), 61 svalBuilder(StateMgr.getSValBuilder()), 62 EntryNode(NULL), 63 currentStmt(NULL), currentStmtIdx(0), currentBuilderContext(0), 64 NSExceptionII(NULL), NSExceptionInstanceRaiseSelectors(NULL), 65 RaiseSel(GetNullarySelector("raise", getContext())), 66 ObjCGCEnabled(gcEnabled), BR(mgr, *this) { 67 68 if (mgr.shouldEagerlyTrimExplodedGraph()) { 69 // Enable eager node reclaimation when constructing the ExplodedGraph. 70 G.enableNodeReclamation(); 71 } 72} 73 74ExprEngine::~ExprEngine() { 75 BR.FlushReports(); 76 delete [] NSExceptionInstanceRaiseSelectors; 77} 78 79//===----------------------------------------------------------------------===// 80// Utility methods. 81//===----------------------------------------------------------------------===// 82 83ProgramStateRef ExprEngine::getInitialState(const LocationContext *InitLoc) { 84 ProgramStateRef state = StateMgr.getInitialState(InitLoc); 85 const Decl *D = InitLoc->getDecl(); 86 87 // Preconditions. 88 // FIXME: It would be nice if we had a more general mechanism to add 89 // such preconditions. Some day. 90 do { 91 92 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 93 // Precondition: the first argument of 'main' is an integer guaranteed 94 // to be > 0. 95 const IdentifierInfo *II = FD->getIdentifier(); 96 if (!II || !(II->getName() == "main" && FD->getNumParams() > 0)) 97 break; 98 99 const ParmVarDecl *PD = FD->getParamDecl(0); 100 QualType T = PD->getType(); 101 if (!T->isIntegerType()) 102 break; 103 104 const MemRegion *R = state->getRegion(PD, InitLoc); 105 if (!R) 106 break; 107 108 SVal V = state->getSVal(loc::MemRegionVal(R)); 109 SVal Constraint_untested = evalBinOp(state, BO_GT, V, 110 svalBuilder.makeZeroVal(T), 111 getContext().IntTy); 112 113 DefinedOrUnknownSVal *Constraint = 114 dyn_cast<DefinedOrUnknownSVal>(&Constraint_untested); 115 116 if (!Constraint) 117 break; 118 119 if (ProgramStateRef newState = state->assume(*Constraint, true)) 120 state = newState; 121 } 122 break; 123 } 124 while (0); 125 126 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 127 // Precondition: 'self' is always non-null upon entry to an Objective-C 128 // method. 129 const ImplicitParamDecl *SelfD = MD->getSelfDecl(); 130 const MemRegion *R = state->getRegion(SelfD, InitLoc); 131 SVal V = state->getSVal(loc::MemRegionVal(R)); 132 133 if (const Loc *LV = dyn_cast<Loc>(&V)) { 134 // Assume that the pointer value in 'self' is non-null. 135 state = state->assume(*LV, true); 136 assert(state && "'self' cannot be null"); 137 } 138 } 139 140 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) { 141 if (!MD->isStatic()) { 142 // Precondition: 'this' is always non-null upon entry to the 143 // top-level function. This is our starting assumption for 144 // analyzing an "open" program. 145 const StackFrameContext *SFC = InitLoc->getCurrentStackFrame(); 146 if (SFC->getParent() == 0) { 147 loc::MemRegionVal L(getCXXThisRegion(MD, SFC)); 148 SVal V = state->getSVal(L); 149 if (const Loc *LV = dyn_cast<Loc>(&V)) { 150 state = state->assume(*LV, true); 151 assert(state && "'this' cannot be null"); 152 } 153 } 154 } 155 } 156 157 return state; 158} 159 160//===----------------------------------------------------------------------===// 161// Top-level transfer function logic (Dispatcher). 162//===----------------------------------------------------------------------===// 163 164/// evalAssume - Called by ConstraintManager. Used to call checker-specific 165/// logic for handling assumptions on symbolic values. 166ProgramStateRef ExprEngine::processAssume(ProgramStateRef state, 167 SVal cond, bool assumption) { 168 return getCheckerManager().runCheckersForEvalAssume(state, cond, assumption); 169} 170 171bool ExprEngine::wantsRegionChangeUpdate(ProgramStateRef state) { 172 return getCheckerManager().wantsRegionChangeUpdate(state); 173} 174 175ProgramStateRef 176ExprEngine::processRegionChanges(ProgramStateRef state, 177 const StoreManager::InvalidatedSymbols *invalidated, 178 ArrayRef<const MemRegion *> Explicits, 179 ArrayRef<const MemRegion *> Regions, 180 const CallOrObjCMessage *Call) { 181 return getCheckerManager().runCheckersForRegionChanges(state, invalidated, 182 Explicits, Regions, Call); 183} 184 185void ExprEngine::printState(raw_ostream &Out, ProgramStateRef State, 186 const char *NL, const char *Sep) { 187 getCheckerManager().runCheckersForPrintState(Out, State, NL, Sep); 188} 189 190void ExprEngine::processEndWorklist(bool hasWorkRemaining) { 191 getCheckerManager().runCheckersForEndAnalysis(G, BR, *this); 192} 193 194void ExprEngine::processCFGElement(const CFGElement E, ExplodedNode *Pred, 195 unsigned StmtIdx, NodeBuilderContext *Ctx) { 196 currentStmtIdx = StmtIdx; 197 currentBuilderContext = Ctx; 198 199 switch (E.getKind()) { 200 case CFGElement::Invalid: 201 llvm_unreachable("Unexpected CFGElement kind."); 202 case CFGElement::Statement: 203 ProcessStmt(const_cast<Stmt*>(E.getAs<CFGStmt>()->getStmt()), Pred); 204 return; 205 case CFGElement::Initializer: 206 ProcessInitializer(E.getAs<CFGInitializer>()->getInitializer(), Pred); 207 return; 208 case CFGElement::AutomaticObjectDtor: 209 case CFGElement::BaseDtor: 210 case CFGElement::MemberDtor: 211 case CFGElement::TemporaryDtor: 212 ProcessImplicitDtor(*E.getAs<CFGImplicitDtor>(), Pred); 213 return; 214 } 215} 216 217static bool shouldRemoveDeadBindings(AnalysisManager &AMgr, 218 const CFGStmt S, 219 const ExplodedNode *Pred, 220 const LocationContext *LC) { 221 222 // Are we never purging state values? 223 if (AMgr.getPurgeMode() == PurgeNone) 224 return false; 225 226 // Is this the beginning of a basic block? 227 if (isa<BlockEntrance>(Pred->getLocation())) 228 return true; 229 230 // Is this on a non-expression? 231 if (!isa<Expr>(S.getStmt())) 232 return true; 233 234 // Is this an expression that is consumed by another expression? If so, 235 // postpone cleaning out the state. 236 ParentMap &PM = LC->getAnalysisDeclContext()->getParentMap(); 237 return !PM.isConsumedExpr(cast<Expr>(S.getStmt())); 238} 239 240void ExprEngine::ProcessStmt(const CFGStmt S, 241 ExplodedNode *Pred) { 242 // Reclaim any unnecessary nodes in the ExplodedGraph. 243 G.reclaimRecentlyAllocatedNodes(); 244 245 currentStmt = S.getStmt(); 246 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(), 247 currentStmt->getLocStart(), 248 "Error evaluating statement"); 249 250 EntryNode = Pred; 251 252 ProgramStateRef EntryState = EntryNode->getState(); 253 CleanedState = EntryState; 254 255 // Create the cleaned state. 256 const LocationContext *LC = EntryNode->getLocationContext(); 257 SymbolReaper SymReaper(LC, currentStmt, SymMgr, getStoreManager()); 258 259 if (shouldRemoveDeadBindings(AMgr, S, Pred, LC)) { 260 getCheckerManager().runCheckersForLiveSymbols(CleanedState, SymReaper); 261 262 const StackFrameContext *SFC = LC->getCurrentStackFrame(); 263 264 // Create a state in which dead bindings are removed from the environment 265 // and the store. TODO: The function should just return new env and store, 266 // not a new state. 267 CleanedState = StateMgr.removeDeadBindings(CleanedState, SFC, SymReaper); 268 } 269 270 // Process any special transfer function for dead symbols. 271 ExplodedNodeSet Tmp; 272 // A tag to track convenience transitions, which can be removed at cleanup. 273 static SimpleProgramPointTag cleanupTag("ExprEngine : Clean Node"); 274 275 if (!SymReaper.hasDeadSymbols()) { 276 // Generate a CleanedNode that has the environment and store cleaned 277 // up. Since no symbols are dead, we can optimize and not clean out 278 // the constraint manager. 279 StmtNodeBuilder Bldr(Pred, Tmp, *currentBuilderContext); 280 Bldr.generateNode(currentStmt, EntryNode, CleanedState, false, &cleanupTag); 281 282 } else { 283 // Call checkers with the non-cleaned state so that they could query the 284 // values of the soon to be dead symbols. 285 ExplodedNodeSet CheckedSet; 286 getCheckerManager().runCheckersForDeadSymbols(CheckedSet, EntryNode, 287 SymReaper, currentStmt, *this); 288 289 // For each node in CheckedSet, generate CleanedNodes that have the 290 // environment, the store, and the constraints cleaned up but have the 291 // user-supplied states as the predecessors. 292 StmtNodeBuilder Bldr(CheckedSet, Tmp, *currentBuilderContext); 293 for (ExplodedNodeSet::const_iterator 294 I = CheckedSet.begin(), E = CheckedSet.end(); I != E; ++I) { 295 ProgramStateRef CheckerState = (*I)->getState(); 296 297 // The constraint manager has not been cleaned up yet, so clean up now. 298 CheckerState = getConstraintManager().removeDeadBindings(CheckerState, 299 SymReaper); 300 301 assert(StateMgr.haveEqualEnvironments(CheckerState, EntryState) && 302 "Checkers are not allowed to modify the Environment as a part of " 303 "checkDeadSymbols processing."); 304 assert(StateMgr.haveEqualStores(CheckerState, EntryState) && 305 "Checkers are not allowed to modify the Store as a part of " 306 "checkDeadSymbols processing."); 307 308 // Create a state based on CleanedState with CheckerState GDM and 309 // generate a transition to that state. 310 ProgramStateRef CleanedCheckerSt = 311 StateMgr.getPersistentStateWithGDM(CleanedState, CheckerState); 312 Bldr.generateNode(currentStmt, *I, CleanedCheckerSt, false, &cleanupTag, 313 ProgramPoint::PostPurgeDeadSymbolsKind); 314 } 315 } 316 317 ExplodedNodeSet Dst; 318 for (ExplodedNodeSet::iterator I=Tmp.begin(), E=Tmp.end(); I!=E; ++I) { 319 ExplodedNodeSet DstI; 320 // Visit the statement. 321 Visit(currentStmt, *I, DstI); 322 Dst.insert(DstI); 323 } 324 325 // Enqueue the new nodes onto the work list. 326 Engine.enqueue(Dst, currentBuilderContext->getBlock(), currentStmtIdx); 327 328 // NULL out these variables to cleanup. 329 CleanedState = NULL; 330 EntryNode = NULL; 331 currentStmt = 0; 332} 333 334void ExprEngine::ProcessInitializer(const CFGInitializer Init, 335 ExplodedNode *Pred) { 336 ExplodedNodeSet Dst; 337 338 // We don't set EntryNode and currentStmt. And we don't clean up state. 339 const CXXCtorInitializer *BMI = Init.getInitializer(); 340 const StackFrameContext *stackFrame = 341 cast<StackFrameContext>(Pred->getLocationContext()); 342 const CXXConstructorDecl *decl = 343 cast<CXXConstructorDecl>(stackFrame->getDecl()); 344 const CXXThisRegion *thisReg = getCXXThisRegion(decl, stackFrame); 345 346 SVal thisVal = Pred->getState()->getSVal(thisReg); 347 348 if (BMI->isAnyMemberInitializer()) { 349 ExplodedNodeSet AfterEval; 350 351 // Evaluate the initializer. 352 Visit(BMI->getInit(), Pred, AfterEval); 353 354 StmtNodeBuilder Bldr(AfterEval, Dst, *currentBuilderContext); 355 for (ExplodedNodeSet::iterator I = AfterEval.begin(), 356 E = AfterEval.end(); I != E; ++I){ 357 ExplodedNode *P = *I; 358 ProgramStateRef state = P->getState(); 359 360 const FieldDecl *FD = BMI->getAnyMember(); 361 362 SVal FieldLoc = state->getLValue(FD, thisVal); 363 SVal InitVal = state->getSVal(BMI->getInit(), Pred->getLocationContext()); 364 state = state->bindLoc(FieldLoc, InitVal); 365 366 // Use a custom node building process. 367 PostInitializer PP(BMI, stackFrame); 368 // Builder automatically add the generated node to the deferred set, 369 // which are processed in the builder's dtor. 370 Bldr.generateNode(PP, P, state); 371 } 372 } else { 373 assert(BMI->isBaseInitializer()); 374 375 // Get the base class declaration. 376 const CXXConstructExpr *ctorExpr = cast<CXXConstructExpr>(BMI->getInit()); 377 378 // Create the base object region. 379 SVal baseVal = 380 getStoreManager().evalDerivedToBase(thisVal, ctorExpr->getType()); 381 const MemRegion *baseReg = baseVal.getAsRegion(); 382 assert(baseReg); 383 384 VisitCXXConstructExpr(ctorExpr, baseReg, Pred, Dst); 385 } 386 387 // Enqueue the new nodes onto the work list. 388 Engine.enqueue(Dst, currentBuilderContext->getBlock(), currentStmtIdx); 389} 390 391void ExprEngine::ProcessImplicitDtor(const CFGImplicitDtor D, 392 ExplodedNode *Pred) { 393 ExplodedNodeSet Dst; 394 switch (D.getKind()) { 395 case CFGElement::AutomaticObjectDtor: 396 ProcessAutomaticObjDtor(cast<CFGAutomaticObjDtor>(D), Pred, Dst); 397 break; 398 case CFGElement::BaseDtor: 399 ProcessBaseDtor(cast<CFGBaseDtor>(D), Pred, Dst); 400 break; 401 case CFGElement::MemberDtor: 402 ProcessMemberDtor(cast<CFGMemberDtor>(D), Pred, Dst); 403 break; 404 case CFGElement::TemporaryDtor: 405 ProcessTemporaryDtor(cast<CFGTemporaryDtor>(D), Pred, Dst); 406 break; 407 default: 408 llvm_unreachable("Unexpected dtor kind."); 409 } 410 411 // Enqueue the new nodes onto the work list. 412 Engine.enqueue(Dst, currentBuilderContext->getBlock(), currentStmtIdx); 413} 414 415void ExprEngine::ProcessAutomaticObjDtor(const CFGAutomaticObjDtor Dtor, 416 ExplodedNode *Pred, 417 ExplodedNodeSet &Dst) { 418 ProgramStateRef state = Pred->getState(); 419 const VarDecl *varDecl = Dtor.getVarDecl(); 420 421 QualType varType = varDecl->getType(); 422 423 if (const ReferenceType *refType = varType->getAs<ReferenceType>()) 424 varType = refType->getPointeeType(); 425 426 const CXXRecordDecl *recordDecl = varType->getAsCXXRecordDecl(); 427 assert(recordDecl && "get CXXRecordDecl fail"); 428 const CXXDestructorDecl *dtorDecl = recordDecl->getDestructor(); 429 430 Loc dest = state->getLValue(varDecl, Pred->getLocationContext()); 431 432 VisitCXXDestructor(dtorDecl, cast<loc::MemRegionVal>(dest).getRegion(), 433 Dtor.getTriggerStmt(), Pred, Dst); 434} 435 436void ExprEngine::ProcessBaseDtor(const CFGBaseDtor D, 437 ExplodedNode *Pred, ExplodedNodeSet &Dst) {} 438 439void ExprEngine::ProcessMemberDtor(const CFGMemberDtor D, 440 ExplodedNode *Pred, ExplodedNodeSet &Dst) {} 441 442void ExprEngine::ProcessTemporaryDtor(const CFGTemporaryDtor D, 443 ExplodedNode *Pred, 444 ExplodedNodeSet &Dst) {} 445 446void ExprEngine::Visit(const Stmt *S, ExplodedNode *Pred, 447 ExplodedNodeSet &DstTop) { 448 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(), 449 S->getLocStart(), 450 "Error evaluating statement"); 451 ExplodedNodeSet Dst; 452 StmtNodeBuilder Bldr(Pred, DstTop, *currentBuilderContext); 453 454 // Expressions to ignore. 455 if (const Expr *Ex = dyn_cast<Expr>(S)) 456 S = Ex->IgnoreParens(); 457 458 // FIXME: add metadata to the CFG so that we can disable 459 // this check when we KNOW that there is no block-level subexpression. 460 // The motivation is that this check requires a hashtable lookup. 461 462 if (S != currentStmt && Pred->getLocationContext()->getCFG()->isBlkExpr(S)) 463 return; 464 465 switch (S->getStmtClass()) { 466 // C++ and ARC stuff we don't support yet. 467 case Expr::ObjCIndirectCopyRestoreExprClass: 468 case Stmt::CXXBindTemporaryExprClass: 469 case Stmt::CXXCatchStmtClass: 470 case Stmt::CXXDependentScopeMemberExprClass: 471 case Stmt::CXXPseudoDestructorExprClass: 472 case Stmt::CXXThrowExprClass: 473 case Stmt::CXXTryStmtClass: 474 case Stmt::CXXTypeidExprClass: 475 case Stmt::CXXUuidofExprClass: 476 case Stmt::CXXUnresolvedConstructExprClass: 477 case Stmt::CXXScalarValueInitExprClass: 478 case Stmt::DependentScopeDeclRefExprClass: 479 case Stmt::UnaryTypeTraitExprClass: 480 case Stmt::BinaryTypeTraitExprClass: 481 case Stmt::ArrayTypeTraitExprClass: 482 case Stmt::ExpressionTraitExprClass: 483 case Stmt::UnresolvedLookupExprClass: 484 case Stmt::UnresolvedMemberExprClass: 485 case Stmt::CXXNoexceptExprClass: 486 case Stmt::PackExpansionExprClass: 487 case Stmt::SubstNonTypeTemplateParmPackExprClass: 488 case Stmt::SEHTryStmtClass: 489 case Stmt::SEHExceptStmtClass: 490 case Stmt::LambdaExprClass: 491 case Stmt::SEHFinallyStmtClass: { 492 const ExplodedNode *node = Bldr.generateNode(S, Pred, Pred->getState()); 493 Engine.addAbortedBlock(node, currentBuilderContext->getBlock()); 494 break; 495 } 496 497 // We don't handle default arguments either yet, but we can fake it 498 // for now by just skipping them. 499 case Stmt::SubstNonTypeTemplateParmExprClass: 500 case Stmt::CXXDefaultArgExprClass: 501 break; 502 503 case Stmt::ParenExprClass: 504 llvm_unreachable("ParenExprs already handled."); 505 case Stmt::GenericSelectionExprClass: 506 llvm_unreachable("GenericSelectionExprs already handled."); 507 // Cases that should never be evaluated simply because they shouldn't 508 // appear in the CFG. 509 case Stmt::BreakStmtClass: 510 case Stmt::CaseStmtClass: 511 case Stmt::CompoundStmtClass: 512 case Stmt::ContinueStmtClass: 513 case Stmt::CXXForRangeStmtClass: 514 case Stmt::DefaultStmtClass: 515 case Stmt::DoStmtClass: 516 case Stmt::ForStmtClass: 517 case Stmt::GotoStmtClass: 518 case Stmt::IfStmtClass: 519 case Stmt::IndirectGotoStmtClass: 520 case Stmt::LabelStmtClass: 521 case Stmt::NoStmtClass: 522 case Stmt::NullStmtClass: 523 case Stmt::SwitchStmtClass: 524 case Stmt::WhileStmtClass: 525 case Expr::MSDependentExistsStmtClass: 526 llvm_unreachable("Stmt should not be in analyzer evaluation loop"); 527 528 case Stmt::GNUNullExprClass: { 529 // GNU __null is a pointer-width integer, not an actual pointer. 530 ProgramStateRef state = Pred->getState(); 531 state = state->BindExpr(S, Pred->getLocationContext(), 532 svalBuilder.makeIntValWithPtrWidth(0, false)); 533 Bldr.generateNode(S, Pred, state); 534 break; 535 } 536 537 case Stmt::ObjCAtSynchronizedStmtClass: 538 Bldr.takeNodes(Pred); 539 VisitObjCAtSynchronizedStmt(cast<ObjCAtSynchronizedStmt>(S), Pred, Dst); 540 Bldr.addNodes(Dst); 541 break; 542 543 case Stmt::ObjCPropertyRefExprClass: 544 // Implicitly handled by Environment::getSVal(). 545 break; 546 547 case Stmt::ImplicitValueInitExprClass: { 548 ProgramStateRef state = Pred->getState(); 549 QualType ty = cast<ImplicitValueInitExpr>(S)->getType(); 550 SVal val = svalBuilder.makeZeroVal(ty); 551 Bldr.generateNode(S, Pred, state->BindExpr(S, Pred->getLocationContext(), 552 val)); 553 break; 554 } 555 556 case Stmt::ExprWithCleanupsClass: 557 Bldr.takeNodes(Pred); 558 Visit(cast<ExprWithCleanups>(S)->getSubExpr(), Pred, Dst); 559 Bldr.addNodes(Dst); 560 break; 561 562 // Cases not handled yet; but will handle some day. 563 case Stmt::DesignatedInitExprClass: 564 case Stmt::ExtVectorElementExprClass: 565 case Stmt::ImaginaryLiteralClass: 566 case Stmt::ObjCAtCatchStmtClass: 567 case Stmt::ObjCAtFinallyStmtClass: 568 case Stmt::ObjCAtTryStmtClass: 569 case Stmt::ObjCAutoreleasePoolStmtClass: 570 case Stmt::ObjCEncodeExprClass: 571 case Stmt::ObjCIsaExprClass: 572 case Stmt::ObjCProtocolExprClass: 573 case Stmt::ObjCSelectorExprClass: 574 case Stmt::ObjCStringLiteralClass: 575 case Stmt::ParenListExprClass: 576 case Stmt::PredefinedExprClass: 577 case Stmt::ShuffleVectorExprClass: 578 case Stmt::VAArgExprClass: 579 case Stmt::CUDAKernelCallExprClass: 580 case Stmt::OpaqueValueExprClass: 581 case Stmt::AsTypeExprClass: 582 case Stmt::AtomicExprClass: 583 // Fall through. 584 585 // Cases we intentionally don't evaluate, since they don't need 586 // to be explicitly evaluated. 587 case Stmt::AddrLabelExprClass: 588 case Stmt::IntegerLiteralClass: 589 case Stmt::CharacterLiteralClass: 590 case Stmt::CXXBoolLiteralExprClass: 591 case Stmt::FloatingLiteralClass: 592 case Stmt::SizeOfPackExprClass: 593 case Stmt::CXXNullPtrLiteralExprClass: 594 // No-op. Simply propagate the current state unchanged. 595 break; 596 597 case Stmt::ArraySubscriptExprClass: 598 Bldr.takeNodes(Pred); 599 VisitLvalArraySubscriptExpr(cast<ArraySubscriptExpr>(S), Pred, Dst); 600 Bldr.addNodes(Dst); 601 break; 602 603 case Stmt::AsmStmtClass: 604 Bldr.takeNodes(Pred); 605 VisitAsmStmt(cast<AsmStmt>(S), Pred, Dst); 606 Bldr.addNodes(Dst); 607 break; 608 609 case Stmt::BlockDeclRefExprClass: { 610 Bldr.takeNodes(Pred); 611 const BlockDeclRefExpr *BE = cast<BlockDeclRefExpr>(S); 612 VisitCommonDeclRefExpr(BE, BE->getDecl(), Pred, Dst); 613 Bldr.addNodes(Dst); 614 break; 615 } 616 617 case Stmt::BlockExprClass: 618 Bldr.takeNodes(Pred); 619 VisitBlockExpr(cast<BlockExpr>(S), Pred, Dst); 620 Bldr.addNodes(Dst); 621 break; 622 623 case Stmt::BinaryOperatorClass: { 624 const BinaryOperator* B = cast<BinaryOperator>(S); 625 if (B->isLogicalOp()) { 626 Bldr.takeNodes(Pred); 627 VisitLogicalExpr(B, Pred, Dst); 628 Bldr.addNodes(Dst); 629 break; 630 } 631 else if (B->getOpcode() == BO_Comma) { 632 ProgramStateRef state = Pred->getState(); 633 Bldr.generateNode(B, Pred, 634 state->BindExpr(B, Pred->getLocationContext(), 635 state->getSVal(B->getRHS(), 636 Pred->getLocationContext()))); 637 break; 638 } 639 640 Bldr.takeNodes(Pred); 641 642 if (AMgr.shouldEagerlyAssume() && 643 (B->isRelationalOp() || B->isEqualityOp())) { 644 ExplodedNodeSet Tmp; 645 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Tmp); 646 evalEagerlyAssume(Dst, Tmp, cast<Expr>(S)); 647 } 648 else 649 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Dst); 650 651 Bldr.addNodes(Dst); 652 break; 653 } 654 655 case Stmt::CallExprClass: 656 case Stmt::CXXOperatorCallExprClass: 657 case Stmt::CXXMemberCallExprClass: { 658 Bldr.takeNodes(Pred); 659 VisitCallExpr(cast<CallExpr>(S), Pred, Dst); 660 Bldr.addNodes(Dst); 661 break; 662 } 663 664 case Stmt::CXXTemporaryObjectExprClass: 665 case Stmt::CXXConstructExprClass: { 666 const CXXConstructExpr *C = cast<CXXConstructExpr>(S); 667 // For block-level CXXConstructExpr, we don't have a destination region. 668 // Let VisitCXXConstructExpr() create one. 669 Bldr.takeNodes(Pred); 670 VisitCXXConstructExpr(C, 0, Pred, Dst); 671 Bldr.addNodes(Dst); 672 break; 673 } 674 675 case Stmt::CXXNewExprClass: { 676 Bldr.takeNodes(Pred); 677 const CXXNewExpr *NE = cast<CXXNewExpr>(S); 678 VisitCXXNewExpr(NE, Pred, Dst); 679 Bldr.addNodes(Dst); 680 break; 681 } 682 683 case Stmt::CXXDeleteExprClass: { 684 Bldr.takeNodes(Pred); 685 const CXXDeleteExpr *CDE = cast<CXXDeleteExpr>(S); 686 VisitCXXDeleteExpr(CDE, Pred, Dst); 687 Bldr.addNodes(Dst); 688 break; 689 } 690 // FIXME: ChooseExpr is really a constant. We need to fix 691 // the CFG do not model them as explicit control-flow. 692 693 case Stmt::ChooseExprClass: { // __builtin_choose_expr 694 Bldr.takeNodes(Pred); 695 const ChooseExpr *C = cast<ChooseExpr>(S); 696 VisitGuardedExpr(C, C->getLHS(), C->getRHS(), Pred, Dst); 697 Bldr.addNodes(Dst); 698 break; 699 } 700 701 case Stmt::CompoundAssignOperatorClass: 702 Bldr.takeNodes(Pred); 703 VisitBinaryOperator(cast<BinaryOperator>(S), Pred, Dst); 704 Bldr.addNodes(Dst); 705 break; 706 707 case Stmt::CompoundLiteralExprClass: 708 Bldr.takeNodes(Pred); 709 VisitCompoundLiteralExpr(cast<CompoundLiteralExpr>(S), Pred, Dst); 710 Bldr.addNodes(Dst); 711 break; 712 713 case Stmt::BinaryConditionalOperatorClass: 714 case Stmt::ConditionalOperatorClass: { // '?' operator 715 Bldr.takeNodes(Pred); 716 const AbstractConditionalOperator *C 717 = cast<AbstractConditionalOperator>(S); 718 VisitGuardedExpr(C, C->getTrueExpr(), C->getFalseExpr(), Pred, Dst); 719 Bldr.addNodes(Dst); 720 break; 721 } 722 723 case Stmt::CXXThisExprClass: 724 Bldr.takeNodes(Pred); 725 VisitCXXThisExpr(cast<CXXThisExpr>(S), Pred, Dst); 726 Bldr.addNodes(Dst); 727 break; 728 729 case Stmt::DeclRefExprClass: { 730 Bldr.takeNodes(Pred); 731 const DeclRefExpr *DE = cast<DeclRefExpr>(S); 732 VisitCommonDeclRefExpr(DE, DE->getDecl(), Pred, Dst); 733 Bldr.addNodes(Dst); 734 break; 735 } 736 737 case Stmt::DeclStmtClass: 738 Bldr.takeNodes(Pred); 739 VisitDeclStmt(cast<DeclStmt>(S), Pred, Dst); 740 Bldr.addNodes(Dst); 741 break; 742 743 case Stmt::ImplicitCastExprClass: 744 case Stmt::CStyleCastExprClass: 745 case Stmt::CXXStaticCastExprClass: 746 case Stmt::CXXDynamicCastExprClass: 747 case Stmt::CXXReinterpretCastExprClass: 748 case Stmt::CXXConstCastExprClass: 749 case Stmt::CXXFunctionalCastExprClass: 750 case Stmt::ObjCBridgedCastExprClass: { 751 Bldr.takeNodes(Pred); 752 const CastExpr *C = cast<CastExpr>(S); 753 // Handle the previsit checks. 754 ExplodedNodeSet dstPrevisit; 755 getCheckerManager().runCheckersForPreStmt(dstPrevisit, Pred, C, *this); 756 757 // Handle the expression itself. 758 ExplodedNodeSet dstExpr; 759 for (ExplodedNodeSet::iterator i = dstPrevisit.begin(), 760 e = dstPrevisit.end(); i != e ; ++i) { 761 VisitCast(C, C->getSubExpr(), *i, dstExpr); 762 } 763 764 // Handle the postvisit checks. 765 getCheckerManager().runCheckersForPostStmt(Dst, dstExpr, C, *this); 766 Bldr.addNodes(Dst); 767 break; 768 } 769 770 case Expr::MaterializeTemporaryExprClass: { 771 Bldr.takeNodes(Pred); 772 const MaterializeTemporaryExpr *Materialize 773 = cast<MaterializeTemporaryExpr>(S); 774 if (!Materialize->getType()->isRecordType()) 775 CreateCXXTemporaryObject(Materialize, Pred, Dst); 776 else 777 Visit(Materialize->GetTemporaryExpr(), Pred, Dst); 778 Bldr.addNodes(Dst); 779 break; 780 } 781 782 case Stmt::InitListExprClass: 783 Bldr.takeNodes(Pred); 784 VisitInitListExpr(cast<InitListExpr>(S), Pred, Dst); 785 Bldr.addNodes(Dst); 786 break; 787 788 case Stmt::MemberExprClass: 789 Bldr.takeNodes(Pred); 790 VisitMemberExpr(cast<MemberExpr>(S), Pred, Dst); 791 Bldr.addNodes(Dst); 792 break; 793 794 case Stmt::ObjCIvarRefExprClass: 795 Bldr.takeNodes(Pred); 796 VisitLvalObjCIvarRefExpr(cast<ObjCIvarRefExpr>(S), Pred, Dst); 797 Bldr.addNodes(Dst); 798 break; 799 800 case Stmt::ObjCForCollectionStmtClass: 801 Bldr.takeNodes(Pred); 802 VisitObjCForCollectionStmt(cast<ObjCForCollectionStmt>(S), Pred, Dst); 803 Bldr.addNodes(Dst); 804 break; 805 806 case Stmt::ObjCMessageExprClass: 807 Bldr.takeNodes(Pred); 808 VisitObjCMessage(cast<ObjCMessageExpr>(S), Pred, Dst); 809 Bldr.addNodes(Dst); 810 break; 811 812 case Stmt::ObjCAtThrowStmtClass: { 813 // FIXME: This is not complete. We basically treat @throw as 814 // an abort. 815 Bldr.generateNode(S, Pred, Pred->getState()); 816 break; 817 } 818 819 case Stmt::ReturnStmtClass: 820 Bldr.takeNodes(Pred); 821 VisitReturnStmt(cast<ReturnStmt>(S), Pred, Dst); 822 Bldr.addNodes(Dst); 823 break; 824 825 case Stmt::OffsetOfExprClass: 826 Bldr.takeNodes(Pred); 827 VisitOffsetOfExpr(cast<OffsetOfExpr>(S), Pred, Dst); 828 Bldr.addNodes(Dst); 829 break; 830 831 case Stmt::UnaryExprOrTypeTraitExprClass: 832 Bldr.takeNodes(Pred); 833 VisitUnaryExprOrTypeTraitExpr(cast<UnaryExprOrTypeTraitExpr>(S), 834 Pred, Dst); 835 Bldr.addNodes(Dst); 836 break; 837 838 case Stmt::StmtExprClass: { 839 const StmtExpr *SE = cast<StmtExpr>(S); 840 841 if (SE->getSubStmt()->body_empty()) { 842 // Empty statement expression. 843 assert(SE->getType() == getContext().VoidTy 844 && "Empty statement expression must have void type."); 845 break; 846 } 847 848 if (Expr *LastExpr = dyn_cast<Expr>(*SE->getSubStmt()->body_rbegin())) { 849 ProgramStateRef state = Pred->getState(); 850 Bldr.generateNode(SE, Pred, 851 state->BindExpr(SE, Pred->getLocationContext(), 852 state->getSVal(LastExpr, 853 Pred->getLocationContext()))); 854 } 855 break; 856 } 857 858 case Stmt::StringLiteralClass: { 859 ProgramStateRef state = Pred->getState(); 860 SVal V = state->getLValue(cast<StringLiteral>(S)); 861 Bldr.generateNode(S, Pred, state->BindExpr(S, Pred->getLocationContext(), 862 V)); 863 return; 864 } 865 866 case Stmt::UnaryOperatorClass: { 867 Bldr.takeNodes(Pred); 868 const UnaryOperator *U = cast<UnaryOperator>(S); 869 if (AMgr.shouldEagerlyAssume() && (U->getOpcode() == UO_LNot)) { 870 ExplodedNodeSet Tmp; 871 VisitUnaryOperator(U, Pred, Tmp); 872 evalEagerlyAssume(Dst, Tmp, U); 873 } 874 else 875 VisitUnaryOperator(U, Pred, Dst); 876 Bldr.addNodes(Dst); 877 break; 878 } 879 880 case Stmt::PseudoObjectExprClass: { 881 Bldr.takeNodes(Pred); 882 ProgramStateRef state = Pred->getState(); 883 const PseudoObjectExpr *PE = cast<PseudoObjectExpr>(S); 884 if (const Expr *Result = PE->getResultExpr()) { 885 SVal V = state->getSVal(Result, Pred->getLocationContext()); 886 Bldr.generateNode(S, Pred, 887 state->BindExpr(S, Pred->getLocationContext(), V)); 888 } 889 else 890 Bldr.generateNode(S, Pred, 891 state->BindExpr(S, Pred->getLocationContext(), 892 UnknownVal())); 893 894 Bldr.addNodes(Dst); 895 break; 896 } 897 } 898} 899 900/// Block entrance. (Update counters). 901void ExprEngine::processCFGBlockEntrance(NodeBuilderWithSinks &nodeBuilder) { 902 903 // FIXME: Refactor this into a checker. 904 ExplodedNode *pred = nodeBuilder.getContext().getPred(); 905 906 if (nodeBuilder.getContext().getCurrentBlockCount() >= AMgr.getMaxVisit()) { 907 static SimpleProgramPointTag tag("ExprEngine : Block count exceeded"); 908 nodeBuilder.generateNode(pred->getState(), pred, &tag, true); 909 } 910} 911 912//===----------------------------------------------------------------------===// 913// Branch processing. 914//===----------------------------------------------------------------------===// 915 916ProgramStateRef ExprEngine::MarkBranch(ProgramStateRef state, 917 const Stmt *Terminator, 918 const LocationContext *LCtx, 919 bool branchTaken) { 920 921 switch (Terminator->getStmtClass()) { 922 default: 923 return state; 924 925 case Stmt::BinaryOperatorClass: { // '&&' and '||' 926 927 const BinaryOperator* B = cast<BinaryOperator>(Terminator); 928 BinaryOperator::Opcode Op = B->getOpcode(); 929 930 assert (Op == BO_LAnd || Op == BO_LOr); 931 932 // For &&, if we take the true branch, then the value of the whole 933 // expression is that of the RHS expression. 934 // 935 // For ||, if we take the false branch, then the value of the whole 936 // expression is that of the RHS expression. 937 938 const Expr *Ex = (Op == BO_LAnd && branchTaken) || 939 (Op == BO_LOr && !branchTaken) 940 ? B->getRHS() : B->getLHS(); 941 942 return state->BindExpr(B, LCtx, UndefinedVal(Ex)); 943 } 944 945 case Stmt::BinaryConditionalOperatorClass: 946 case Stmt::ConditionalOperatorClass: { // ?: 947 const AbstractConditionalOperator* C 948 = cast<AbstractConditionalOperator>(Terminator); 949 950 // For ?, if branchTaken == true then the value is either the LHS or 951 // the condition itself. (GNU extension). 952 953 const Expr *Ex; 954 955 if (branchTaken) 956 Ex = C->getTrueExpr(); 957 else 958 Ex = C->getFalseExpr(); 959 960 return state->BindExpr(C, LCtx, UndefinedVal(Ex)); 961 } 962 963 case Stmt::ChooseExprClass: { // ?: 964 965 const ChooseExpr *C = cast<ChooseExpr>(Terminator); 966 967 const Expr *Ex = branchTaken ? C->getLHS() : C->getRHS(); 968 return state->BindExpr(C, LCtx, UndefinedVal(Ex)); 969 } 970 } 971} 972 973/// RecoverCastedSymbol - A helper function for ProcessBranch that is used 974/// to try to recover some path-sensitivity for casts of symbolic 975/// integers that promote their values (which are currently not tracked well). 976/// This function returns the SVal bound to Condition->IgnoreCasts if all the 977// cast(s) did was sign-extend the original value. 978static SVal RecoverCastedSymbol(ProgramStateManager& StateMgr, 979 ProgramStateRef state, 980 const Stmt *Condition, 981 const LocationContext *LCtx, 982 ASTContext &Ctx) { 983 984 const Expr *Ex = dyn_cast<Expr>(Condition); 985 if (!Ex) 986 return UnknownVal(); 987 988 uint64_t bits = 0; 989 bool bitsInit = false; 990 991 while (const CastExpr *CE = dyn_cast<CastExpr>(Ex)) { 992 QualType T = CE->getType(); 993 994 if (!T->isIntegerType()) 995 return UnknownVal(); 996 997 uint64_t newBits = Ctx.getTypeSize(T); 998 if (!bitsInit || newBits < bits) { 999 bitsInit = true; 1000 bits = newBits; 1001 } 1002 1003 Ex = CE->getSubExpr(); 1004 } 1005 1006 // We reached a non-cast. Is it a symbolic value? 1007 QualType T = Ex->getType(); 1008 1009 if (!bitsInit || !T->isIntegerType() || Ctx.getTypeSize(T) > bits) 1010 return UnknownVal(); 1011 1012 return state->getSVal(Ex, LCtx); 1013} 1014 1015void ExprEngine::processBranch(const Stmt *Condition, const Stmt *Term, 1016 NodeBuilderContext& BldCtx, 1017 ExplodedNode *Pred, 1018 ExplodedNodeSet &Dst, 1019 const CFGBlock *DstT, 1020 const CFGBlock *DstF) { 1021 currentBuilderContext = &BldCtx; 1022 1023 // Check for NULL conditions; e.g. "for(;;)" 1024 if (!Condition) { 1025 BranchNodeBuilder NullCondBldr(Pred, Dst, BldCtx, DstT, DstF); 1026 NullCondBldr.markInfeasible(false); 1027 NullCondBldr.generateNode(Pred->getState(), true, Pred); 1028 return; 1029 } 1030 1031 PrettyStackTraceLoc CrashInfo(getContext().getSourceManager(), 1032 Condition->getLocStart(), 1033 "Error evaluating branch"); 1034 1035 ExplodedNodeSet CheckersOutSet; 1036 getCheckerManager().runCheckersForBranchCondition(Condition, CheckersOutSet, 1037 Pred, *this); 1038 // We generated only sinks. 1039 if (CheckersOutSet.empty()) 1040 return; 1041 1042 BranchNodeBuilder builder(CheckersOutSet, Dst, BldCtx, DstT, DstF); 1043 for (NodeBuilder::iterator I = CheckersOutSet.begin(), 1044 E = CheckersOutSet.end(); E != I; ++I) { 1045 ExplodedNode *PredI = *I; 1046 1047 if (PredI->isSink()) 1048 continue; 1049 1050 ProgramStateRef PrevState = Pred->getState(); 1051 SVal X = PrevState->getSVal(Condition, Pred->getLocationContext()); 1052 1053 if (X.isUnknownOrUndef()) { 1054 // Give it a chance to recover from unknown. 1055 if (const Expr *Ex = dyn_cast<Expr>(Condition)) { 1056 if (Ex->getType()->isIntegerType()) { 1057 // Try to recover some path-sensitivity. Right now casts of symbolic 1058 // integers that promote their values are currently not tracked well. 1059 // If 'Condition' is such an expression, try and recover the 1060 // underlying value and use that instead. 1061 SVal recovered = RecoverCastedSymbol(getStateManager(), 1062 PrevState, Condition, 1063 Pred->getLocationContext(), 1064 getContext()); 1065 1066 if (!recovered.isUnknown()) { 1067 X = recovered; 1068 } 1069 } 1070 } 1071 } 1072 1073 const LocationContext *LCtx = PredI->getLocationContext(); 1074 1075 // If the condition is still unknown, give up. 1076 if (X.isUnknownOrUndef()) { 1077 builder.generateNode(MarkBranch(PrevState, Term, LCtx, true), 1078 true, PredI); 1079 builder.generateNode(MarkBranch(PrevState, Term, LCtx, false), 1080 false, PredI); 1081 continue; 1082 } 1083 1084 DefinedSVal V = cast<DefinedSVal>(X); 1085 1086 // Process the true branch. 1087 if (builder.isFeasible(true)) { 1088 if (ProgramStateRef state = PrevState->assume(V, true)) 1089 builder.generateNode(MarkBranch(state, Term, LCtx, true), 1090 true, PredI); 1091 else 1092 builder.markInfeasible(true); 1093 } 1094 1095 // Process the false branch. 1096 if (builder.isFeasible(false)) { 1097 if (ProgramStateRef state = PrevState->assume(V, false)) 1098 builder.generateNode(MarkBranch(state, Term, LCtx, false), 1099 false, PredI); 1100 else 1101 builder.markInfeasible(false); 1102 } 1103 } 1104 currentBuilderContext = 0; 1105} 1106 1107/// processIndirectGoto - Called by CoreEngine. Used to generate successor 1108/// nodes by processing the 'effects' of a computed goto jump. 1109void ExprEngine::processIndirectGoto(IndirectGotoNodeBuilder &builder) { 1110 1111 ProgramStateRef state = builder.getState(); 1112 SVal V = state->getSVal(builder.getTarget(), builder.getLocationContext()); 1113 1114 // Three possibilities: 1115 // 1116 // (1) We know the computed label. 1117 // (2) The label is NULL (or some other constant), or Undefined. 1118 // (3) We have no clue about the label. Dispatch to all targets. 1119 // 1120 1121 typedef IndirectGotoNodeBuilder::iterator iterator; 1122 1123 if (isa<loc::GotoLabel>(V)) { 1124 const LabelDecl *L = cast<loc::GotoLabel>(V).getLabel(); 1125 1126 for (iterator I = builder.begin(), E = builder.end(); I != E; ++I) { 1127 if (I.getLabel() == L) { 1128 builder.generateNode(I, state); 1129 return; 1130 } 1131 } 1132 1133 llvm_unreachable("No block with label."); 1134 } 1135 1136 if (isa<loc::ConcreteInt>(V) || isa<UndefinedVal>(V)) { 1137 // Dispatch to the first target and mark it as a sink. 1138 //ExplodedNode* N = builder.generateNode(builder.begin(), state, true); 1139 // FIXME: add checker visit. 1140 // UndefBranches.insert(N); 1141 return; 1142 } 1143 1144 // This is really a catch-all. We don't support symbolics yet. 1145 // FIXME: Implement dispatch for symbolic pointers. 1146 1147 for (iterator I=builder.begin(), E=builder.end(); I != E; ++I) 1148 builder.generateNode(I, state); 1149} 1150 1151/// ProcessEndPath - Called by CoreEngine. Used to generate end-of-path 1152/// nodes when the control reaches the end of a function. 1153void ExprEngine::processEndOfFunction(NodeBuilderContext& BC) { 1154 StateMgr.EndPath(BC.Pred->getState()); 1155 ExplodedNodeSet Dst; 1156 getCheckerManager().runCheckersForEndPath(BC, Dst, *this); 1157 Engine.enqueueEndOfFunction(Dst); 1158} 1159 1160/// ProcessSwitch - Called by CoreEngine. Used to generate successor 1161/// nodes by processing the 'effects' of a switch statement. 1162void ExprEngine::processSwitch(SwitchNodeBuilder& builder) { 1163 typedef SwitchNodeBuilder::iterator iterator; 1164 ProgramStateRef state = builder.getState(); 1165 const Expr *CondE = builder.getCondition(); 1166 SVal CondV_untested = state->getSVal(CondE, builder.getLocationContext()); 1167 1168 if (CondV_untested.isUndef()) { 1169 //ExplodedNode* N = builder.generateDefaultCaseNode(state, true); 1170 // FIXME: add checker 1171 //UndefBranches.insert(N); 1172 1173 return; 1174 } 1175 DefinedOrUnknownSVal CondV = cast<DefinedOrUnknownSVal>(CondV_untested); 1176 1177 ProgramStateRef DefaultSt = state; 1178 1179 iterator I = builder.begin(), EI = builder.end(); 1180 bool defaultIsFeasible = I == EI; 1181 1182 for ( ; I != EI; ++I) { 1183 // Successor may be pruned out during CFG construction. 1184 if (!I.getBlock()) 1185 continue; 1186 1187 const CaseStmt *Case = I.getCase(); 1188 1189 // Evaluate the LHS of the case value. 1190 llvm::APSInt V1 = Case->getLHS()->EvaluateKnownConstInt(getContext()); 1191 assert(V1.getBitWidth() == getContext().getTypeSize(CondE->getType())); 1192 1193 // Get the RHS of the case, if it exists. 1194 llvm::APSInt V2; 1195 if (const Expr *E = Case->getRHS()) 1196 V2 = E->EvaluateKnownConstInt(getContext()); 1197 else 1198 V2 = V1; 1199 1200 // FIXME: Eventually we should replace the logic below with a range 1201 // comparison, rather than concretize the values within the range. 1202 // This should be easy once we have "ranges" for NonLVals. 1203 1204 do { 1205 nonloc::ConcreteInt CaseVal(getBasicVals().getValue(V1)); 1206 DefinedOrUnknownSVal Res = svalBuilder.evalEQ(DefaultSt ? DefaultSt : state, 1207 CondV, CaseVal); 1208 1209 // Now "assume" that the case matches. 1210 if (ProgramStateRef stateNew = state->assume(Res, true)) { 1211 builder.generateCaseStmtNode(I, stateNew); 1212 1213 // If CondV evaluates to a constant, then we know that this 1214 // is the *only* case that we can take, so stop evaluating the 1215 // others. 1216 if (isa<nonloc::ConcreteInt>(CondV)) 1217 return; 1218 } 1219 1220 // Now "assume" that the case doesn't match. Add this state 1221 // to the default state (if it is feasible). 1222 if (DefaultSt) { 1223 if (ProgramStateRef stateNew = DefaultSt->assume(Res, false)) { 1224 defaultIsFeasible = true; 1225 DefaultSt = stateNew; 1226 } 1227 else { 1228 defaultIsFeasible = false; 1229 DefaultSt = NULL; 1230 } 1231 } 1232 1233 // Concretize the next value in the range. 1234 if (V1 == V2) 1235 break; 1236 1237 ++V1; 1238 assert (V1 <= V2); 1239 1240 } while (true); 1241 } 1242 1243 if (!defaultIsFeasible) 1244 return; 1245 1246 // If we have switch(enum value), the default branch is not 1247 // feasible if all of the enum constants not covered by 'case:' statements 1248 // are not feasible values for the switch condition. 1249 // 1250 // Note that this isn't as accurate as it could be. Even if there isn't 1251 // a case for a particular enum value as long as that enum value isn't 1252 // feasible then it shouldn't be considered for making 'default:' reachable. 1253 const SwitchStmt *SS = builder.getSwitch(); 1254 const Expr *CondExpr = SS->getCond()->IgnoreParenImpCasts(); 1255 if (CondExpr->getType()->getAs<EnumType>()) { 1256 if (SS->isAllEnumCasesCovered()) 1257 return; 1258 } 1259 1260 builder.generateDefaultCaseNode(DefaultSt); 1261} 1262 1263//===----------------------------------------------------------------------===// 1264// Transfer functions: Loads and stores. 1265//===----------------------------------------------------------------------===// 1266 1267void ExprEngine::VisitCommonDeclRefExpr(const Expr *Ex, const NamedDecl *D, 1268 ExplodedNode *Pred, 1269 ExplodedNodeSet &Dst) { 1270 StmtNodeBuilder Bldr(Pred, Dst, *currentBuilderContext); 1271 1272 ProgramStateRef state = Pred->getState(); 1273 const LocationContext *LCtx = Pred->getLocationContext(); 1274 1275 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1276 assert(Ex->isLValue()); 1277 SVal V = state->getLValue(VD, Pred->getLocationContext()); 1278 1279 // For references, the 'lvalue' is the pointer address stored in the 1280 // reference region. 1281 if (VD->getType()->isReferenceType()) { 1282 if (const MemRegion *R = V.getAsRegion()) 1283 V = state->getSVal(R); 1284 else 1285 V = UnknownVal(); 1286 } 1287 1288 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), false, 0, 1289 ProgramPoint::PostLValueKind); 1290 return; 1291 } 1292 if (const EnumConstantDecl *ED = dyn_cast<EnumConstantDecl>(D)) { 1293 assert(!Ex->isLValue()); 1294 SVal V = svalBuilder.makeIntVal(ED->getInitVal()); 1295 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V)); 1296 return; 1297 } 1298 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1299 SVal V = svalBuilder.getFunctionPointer(FD); 1300 Bldr.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V), false, 0, 1301 ProgramPoint::PostLValueKind); 1302 return; 1303 } 1304 assert (false && 1305 "ValueDecl support for this ValueDecl not implemented."); 1306} 1307 1308/// VisitArraySubscriptExpr - Transfer function for array accesses 1309void ExprEngine::VisitLvalArraySubscriptExpr(const ArraySubscriptExpr *A, 1310 ExplodedNode *Pred, 1311 ExplodedNodeSet &Dst){ 1312 1313 const Expr *Base = A->getBase()->IgnoreParens(); 1314 const Expr *Idx = A->getIdx()->IgnoreParens(); 1315 1316 1317 ExplodedNodeSet checkerPreStmt; 1318 getCheckerManager().runCheckersForPreStmt(checkerPreStmt, Pred, A, *this); 1319 1320 StmtNodeBuilder Bldr(checkerPreStmt, Dst, *currentBuilderContext); 1321 1322 for (ExplodedNodeSet::iterator it = checkerPreStmt.begin(), 1323 ei = checkerPreStmt.end(); it != ei; ++it) { 1324 const LocationContext *LCtx = (*it)->getLocationContext(); 1325 ProgramStateRef state = (*it)->getState(); 1326 SVal V = state->getLValue(A->getType(), 1327 state->getSVal(Idx, LCtx), 1328 state->getSVal(Base, LCtx)); 1329 assert(A->isLValue()); 1330 Bldr.generateNode(A, *it, state->BindExpr(A, LCtx, V), 1331 false, 0, ProgramPoint::PostLValueKind); 1332 } 1333} 1334 1335/// VisitMemberExpr - Transfer function for member expressions. 1336void ExprEngine::VisitMemberExpr(const MemberExpr *M, ExplodedNode *Pred, 1337 ExplodedNodeSet &TopDst) { 1338 1339 StmtNodeBuilder Bldr(Pred, TopDst, *currentBuilderContext); 1340 ExplodedNodeSet Dst; 1341 Decl *member = M->getMemberDecl(); 1342 if (VarDecl *VD = dyn_cast<VarDecl>(member)) { 1343 assert(M->isLValue()); 1344 Bldr.takeNodes(Pred); 1345 VisitCommonDeclRefExpr(M, VD, Pred, Dst); 1346 Bldr.addNodes(Dst); 1347 return; 1348 } 1349 1350 FieldDecl *field = dyn_cast<FieldDecl>(member); 1351 if (!field) // FIXME: skipping member expressions for non-fields 1352 return; 1353 1354 Expr *baseExpr = M->getBase()->IgnoreParens(); 1355 ProgramStateRef state = Pred->getState(); 1356 const LocationContext *LCtx = Pred->getLocationContext(); 1357 SVal baseExprVal = state->getSVal(baseExpr, Pred->getLocationContext()); 1358 if (isa<nonloc::LazyCompoundVal>(baseExprVal) || 1359 isa<nonloc::CompoundVal>(baseExprVal) || 1360 // FIXME: This can originate by conjuring a symbol for an unknown 1361 // temporary struct object, see test/Analysis/fields.c: 1362 // (p = getit()).x 1363 isa<nonloc::SymbolVal>(baseExprVal)) { 1364 Bldr.generateNode(M, Pred, state->BindExpr(M, LCtx, UnknownVal())); 1365 return; 1366 } 1367 1368 // FIXME: Should we insert some assumption logic in here to determine 1369 // if "Base" is a valid piece of memory? Before we put this assumption 1370 // later when using FieldOffset lvals (which we no longer have). 1371 1372 // For all other cases, compute an lvalue. 1373 SVal L = state->getLValue(field, baseExprVal); 1374 if (M->isLValue()) 1375 Bldr.generateNode(M, Pred, state->BindExpr(M, LCtx, L), false, 0, 1376 ProgramPoint::PostLValueKind); 1377 else { 1378 Bldr.takeNodes(Pred); 1379 evalLoad(Dst, M, Pred, state, L); 1380 Bldr.addNodes(Dst); 1381 } 1382} 1383 1384/// evalBind - Handle the semantics of binding a value to a specific location. 1385/// This method is used by evalStore and (soon) VisitDeclStmt, and others. 1386void ExprEngine::evalBind(ExplodedNodeSet &Dst, const Stmt *StoreE, 1387 ExplodedNode *Pred, 1388 SVal location, SVal Val, bool atDeclInit, 1389 ProgramPoint::Kind PointKind) { 1390 1391 // Do a previsit of the bind. 1392 ExplodedNodeSet CheckedSet; 1393 getCheckerManager().runCheckersForBind(CheckedSet, Pred, location, Val, 1394 StoreE, *this, PointKind); 1395 1396 // TODO:AZ Remove TmpDst after NB refactoring is done. 1397 ExplodedNodeSet TmpDst; 1398 StmtNodeBuilder Bldr(CheckedSet, TmpDst, *currentBuilderContext); 1399 1400 for (ExplodedNodeSet::iterator I = CheckedSet.begin(), E = CheckedSet.end(); 1401 I!=E; ++I) { 1402 ProgramStateRef state = (*I)->getState(); 1403 1404 if (atDeclInit) { 1405 const VarRegion *VR = 1406 cast<VarRegion>(cast<loc::MemRegionVal>(location).getRegion()); 1407 1408 state = state->bindDecl(VR, Val); 1409 } else { 1410 state = state->bindLoc(location, Val); 1411 } 1412 1413 Bldr.generateNode(StoreE, *I, state, false, 0, PointKind); 1414 } 1415 1416 Dst.insert(TmpDst); 1417} 1418 1419/// evalStore - Handle the semantics of a store via an assignment. 1420/// @param Dst The node set to store generated state nodes 1421/// @param AssignE The assignment expression if the store happens in an 1422/// assignment. 1423/// @param LocatioinE The location expression that is stored to. 1424/// @param state The current simulation state 1425/// @param location The location to store the value 1426/// @param Val The value to be stored 1427void ExprEngine::evalStore(ExplodedNodeSet &Dst, const Expr *AssignE, 1428 const Expr *LocationE, 1429 ExplodedNode *Pred, 1430 ProgramStateRef state, SVal location, SVal Val, 1431 const ProgramPointTag *tag) { 1432 // Proceed with the store. We use AssignE as the anchor for the PostStore 1433 // ProgramPoint if it is non-NULL, and LocationE otherwise. 1434 const Expr *StoreE = AssignE ? AssignE : LocationE; 1435 1436 if (isa<loc::ObjCPropRef>(location)) { 1437 loc::ObjCPropRef prop = cast<loc::ObjCPropRef>(location); 1438 return VisitObjCMessage(ObjCPropertySetter(prop.getPropRefExpr(), 1439 StoreE, Val), Pred, Dst); 1440 } 1441 1442 // Evaluate the location (checks for bad dereferences). 1443 ExplodedNodeSet Tmp; 1444 evalLocation(Tmp, LocationE, Pred, state, location, tag, false); 1445 1446 if (Tmp.empty()) 1447 return; 1448 1449 if (location.isUndef()) 1450 return; 1451 1452 for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI) 1453 evalBind(Dst, StoreE, *NI, location, Val, false, 1454 ProgramPoint::PostStoreKind); 1455} 1456 1457void ExprEngine::evalLoad(ExplodedNodeSet &Dst, const Expr *Ex, 1458 ExplodedNode *Pred, 1459 ProgramStateRef state, SVal location, 1460 const ProgramPointTag *tag, QualType LoadTy) { 1461 assert(!isa<NonLoc>(location) && "location cannot be a NonLoc."); 1462 1463 if (isa<loc::ObjCPropRef>(location)) { 1464 loc::ObjCPropRef prop = cast<loc::ObjCPropRef>(location); 1465 return VisitObjCMessage(ObjCPropertyGetter(prop.getPropRefExpr(), Ex), 1466 Pred, Dst); 1467 } 1468 1469 // Are we loading from a region? This actually results in two loads; one 1470 // to fetch the address of the referenced value and one to fetch the 1471 // referenced value. 1472 if (const TypedValueRegion *TR = 1473 dyn_cast_or_null<TypedValueRegion>(location.getAsRegion())) { 1474 1475 QualType ValTy = TR->getValueType(); 1476 if (const ReferenceType *RT = ValTy->getAs<ReferenceType>()) { 1477 static SimpleProgramPointTag 1478 loadReferenceTag("ExprEngine : Load Reference"); 1479 ExplodedNodeSet Tmp; 1480 evalLoadCommon(Tmp, Ex, Pred, state, location, &loadReferenceTag, 1481 getContext().getPointerType(RT->getPointeeType())); 1482 1483 // Perform the load from the referenced value. 1484 for (ExplodedNodeSet::iterator I=Tmp.begin(), E=Tmp.end() ; I!=E; ++I) { 1485 state = (*I)->getState(); 1486 location = state->getSVal(Ex, (*I)->getLocationContext()); 1487 evalLoadCommon(Dst, Ex, *I, state, location, tag, LoadTy); 1488 } 1489 return; 1490 } 1491 } 1492 1493 evalLoadCommon(Dst, Ex, Pred, state, location, tag, LoadTy); 1494} 1495 1496void ExprEngine::evalLoadCommon(ExplodedNodeSet &Dst, const Expr *Ex, 1497 ExplodedNode *Pred, 1498 ProgramStateRef state, SVal location, 1499 const ProgramPointTag *tag, QualType LoadTy) { 1500 1501 // Evaluate the location (checks for bad dereferences). 1502 ExplodedNodeSet Tmp; 1503 evalLocation(Tmp, Ex, Pred, state, location, tag, true); 1504 if (Tmp.empty()) 1505 return; 1506 1507 StmtNodeBuilder Bldr(Tmp, Dst, *currentBuilderContext); 1508 if (location.isUndef()) 1509 return; 1510 1511 // Proceed with the load. 1512 for (ExplodedNodeSet::iterator NI=Tmp.begin(), NE=Tmp.end(); NI!=NE; ++NI) { 1513 state = (*NI)->getState(); 1514 const LocationContext *LCtx = (*NI)->getLocationContext(); 1515 1516 if (location.isUnknown()) { 1517 // This is important. We must nuke the old binding. 1518 Bldr.generateNode(Ex, *NI, state->BindExpr(Ex, LCtx, UnknownVal()), 1519 false, tag, ProgramPoint::PostLoadKind); 1520 } 1521 else { 1522 if (LoadTy.isNull()) 1523 LoadTy = Ex->getType(); 1524 SVal V = state->getSVal(cast<Loc>(location), LoadTy); 1525 Bldr.generateNode(Ex, *NI, state->bindExprAndLocation(Ex, LCtx, 1526 location, V), 1527 false, tag, ProgramPoint::PostLoadKind); 1528 } 1529 } 1530} 1531 1532void ExprEngine::evalLocation(ExplodedNodeSet &Dst, const Stmt *S, 1533 ExplodedNode *Pred, 1534 ProgramStateRef state, SVal location, 1535 const ProgramPointTag *tag, bool isLoad) { 1536 StmtNodeBuilder BldrTop(Pred, Dst, *currentBuilderContext); 1537 // Early checks for performance reason. 1538 if (location.isUnknown()) { 1539 return; 1540 } 1541 1542 ExplodedNodeSet Src; 1543 BldrTop.takeNodes(Pred); 1544 StmtNodeBuilder Bldr(Pred, Src, *currentBuilderContext); 1545 if (Pred->getState() != state) { 1546 // Associate this new state with an ExplodedNode. 1547 // FIXME: If I pass null tag, the graph is incorrect, e.g for 1548 // int *p; 1549 // p = 0; 1550 // *p = 0xDEADBEEF; 1551 // "p = 0" is not noted as "Null pointer value stored to 'p'" but 1552 // instead "int *p" is noted as 1553 // "Variable 'p' initialized to a null pointer value" 1554 1555 // FIXME: why is 'tag' not used instead of etag? 1556 static SimpleProgramPointTag etag("ExprEngine: Location"); 1557 1558 Bldr.generateNode(S, Pred, state, false, &etag); 1559 } 1560 ExplodedNodeSet Tmp; 1561 getCheckerManager().runCheckersForLocation(Tmp, Src, location, isLoad, S, 1562 *this); 1563 BldrTop.addNodes(Tmp); 1564} 1565 1566std::pair<const ProgramPointTag *, const ProgramPointTag*> 1567ExprEngine::getEagerlyAssumeTags() { 1568 static SimpleProgramPointTag 1569 EagerlyAssumeTrue("ExprEngine : Eagerly Assume True"), 1570 EagerlyAssumeFalse("ExprEngine : Eagerly Assume False"); 1571 return std::make_pair(&EagerlyAssumeTrue, &EagerlyAssumeFalse); 1572} 1573 1574void ExprEngine::evalEagerlyAssume(ExplodedNodeSet &Dst, ExplodedNodeSet &Src, 1575 const Expr *Ex) { 1576 StmtNodeBuilder Bldr(Src, Dst, *currentBuilderContext); 1577 1578 for (ExplodedNodeSet::iterator I=Src.begin(), E=Src.end(); I!=E; ++I) { 1579 ExplodedNode *Pred = *I; 1580 // Test if the previous node was as the same expression. This can happen 1581 // when the expression fails to evaluate to anything meaningful and 1582 // (as an optimization) we don't generate a node. 1583 ProgramPoint P = Pred->getLocation(); 1584 if (!isa<PostStmt>(P) || cast<PostStmt>(P).getStmt() != Ex) { 1585 continue; 1586 } 1587 1588 ProgramStateRef state = Pred->getState(); 1589 SVal V = state->getSVal(Ex, Pred->getLocationContext()); 1590 nonloc::SymbolVal *SEV = dyn_cast<nonloc::SymbolVal>(&V); 1591 if (SEV && SEV->isExpression()) { 1592 const std::pair<const ProgramPointTag *, const ProgramPointTag*> &tags = 1593 getEagerlyAssumeTags(); 1594 1595 // First assume that the condition is true. 1596 if (ProgramStateRef StateTrue = state->assume(*SEV, true)) { 1597 SVal Val = svalBuilder.makeIntVal(1U, Ex->getType()); 1598 StateTrue = StateTrue->BindExpr(Ex, Pred->getLocationContext(), Val); 1599 Bldr.generateNode(Ex, Pred, StateTrue, false, tags.first); 1600 } 1601 1602 // Next, assume that the condition is false. 1603 if (ProgramStateRef StateFalse = state->assume(*SEV, false)) { 1604 SVal Val = svalBuilder.makeIntVal(0U, Ex->getType()); 1605 StateFalse = StateFalse->BindExpr(Ex, Pred->getLocationContext(), Val); 1606 Bldr.generateNode(Ex, Pred, StateFalse, false, tags.second); 1607 } 1608 } 1609 } 1610} 1611 1612void ExprEngine::VisitAsmStmt(const AsmStmt *A, ExplodedNode *Pred, 1613 ExplodedNodeSet &Dst) { 1614 VisitAsmStmtHelperOutputs(A, A->begin_outputs(), A->end_outputs(), Pred, Dst); 1615} 1616 1617void ExprEngine::VisitAsmStmtHelperOutputs(const AsmStmt *A, 1618 AsmStmt::const_outputs_iterator I, 1619 AsmStmt::const_outputs_iterator E, 1620 ExplodedNode *Pred, ExplodedNodeSet &Dst) { 1621 if (I == E) { 1622 VisitAsmStmtHelperInputs(A, A->begin_inputs(), A->end_inputs(), Pred, Dst); 1623 return; 1624 } 1625 1626 ExplodedNodeSet Tmp; 1627 Visit(*I, Pred, Tmp); 1628 ++I; 1629 1630 for (ExplodedNodeSet::iterator NI = Tmp.begin(), NE = Tmp.end();NI != NE;++NI) 1631 VisitAsmStmtHelperOutputs(A, I, E, *NI, Dst); 1632} 1633 1634void ExprEngine::VisitAsmStmtHelperInputs(const AsmStmt *A, 1635 AsmStmt::const_inputs_iterator I, 1636 AsmStmt::const_inputs_iterator E, 1637 ExplodedNode *Pred, 1638 ExplodedNodeSet &Dst) { 1639 if (I == E) { 1640 StmtNodeBuilder Bldr(Pred, Dst, *currentBuilderContext); 1641 // We have processed both the inputs and the outputs. All of the outputs 1642 // should evaluate to Locs. Nuke all of their values. 1643 1644 // FIXME: Some day in the future it would be nice to allow a "plug-in" 1645 // which interprets the inline asm and stores proper results in the 1646 // outputs. 1647 1648 ProgramStateRef state = Pred->getState(); 1649 1650 for (AsmStmt::const_outputs_iterator OI = A->begin_outputs(), 1651 OE = A->end_outputs(); OI != OE; ++OI) { 1652 1653 SVal X = state->getSVal(*OI, Pred->getLocationContext()); 1654 assert (!isa<NonLoc>(X)); // Should be an Lval, or unknown, undef. 1655 1656 if (isa<Loc>(X)) 1657 state = state->bindLoc(cast<Loc>(X), UnknownVal()); 1658 } 1659 1660 Bldr.generateNode(A, Pred, state); 1661 return; 1662 } 1663 1664 ExplodedNodeSet Tmp; 1665 Visit(*I, Pred, Tmp); 1666 1667 ++I; 1668 1669 for (ExplodedNodeSet::iterator NI = Tmp.begin(), NE = Tmp.end(); NI!=NE; ++NI) 1670 VisitAsmStmtHelperInputs(A, I, E, *NI, Dst); 1671} 1672 1673 1674//===----------------------------------------------------------------------===// 1675// Visualization. 1676//===----------------------------------------------------------------------===// 1677 1678#ifndef NDEBUG 1679static ExprEngine* GraphPrintCheckerState; 1680static SourceManager* GraphPrintSourceManager; 1681 1682namespace llvm { 1683template<> 1684struct DOTGraphTraits<ExplodedNode*> : 1685 public DefaultDOTGraphTraits { 1686 1687 DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {} 1688 1689 // FIXME: Since we do not cache error nodes in ExprEngine now, this does not 1690 // work. 1691 static std::string getNodeAttributes(const ExplodedNode *N, void*) { 1692 1693#if 0 1694 // FIXME: Replace with a general scheme to tell if the node is 1695 // an error node. 1696 if (GraphPrintCheckerState->isImplicitNullDeref(N) || 1697 GraphPrintCheckerState->isExplicitNullDeref(N) || 1698 GraphPrintCheckerState->isUndefDeref(N) || 1699 GraphPrintCheckerState->isUndefStore(N) || 1700 GraphPrintCheckerState->isUndefControlFlow(N) || 1701 GraphPrintCheckerState->isUndefResult(N) || 1702 GraphPrintCheckerState->isBadCall(N) || 1703 GraphPrintCheckerState->isUndefArg(N)) 1704 return "color=\"red\",style=\"filled\""; 1705 1706 if (GraphPrintCheckerState->isNoReturnCall(N)) 1707 return "color=\"blue\",style=\"filled\""; 1708#endif 1709 return ""; 1710 } 1711 1712 static std::string getNodeLabel(const ExplodedNode *N, void*){ 1713 1714 std::string sbuf; 1715 llvm::raw_string_ostream Out(sbuf); 1716 1717 // Program Location. 1718 ProgramPoint Loc = N->getLocation(); 1719 1720 switch (Loc.getKind()) { 1721 case ProgramPoint::BlockEntranceKind: 1722 Out << "Block Entrance: B" 1723 << cast<BlockEntrance>(Loc).getBlock()->getBlockID(); 1724 break; 1725 1726 case ProgramPoint::BlockExitKind: 1727 assert (false); 1728 break; 1729 1730 case ProgramPoint::CallEnterKind: 1731 Out << "CallEnter"; 1732 break; 1733 1734 case ProgramPoint::CallExitKind: 1735 Out << "CallExit"; 1736 break; 1737 1738 default: { 1739 if (StmtPoint *L = dyn_cast<StmtPoint>(&Loc)) { 1740 const Stmt *S = L->getStmt(); 1741 SourceLocation SLoc = S->getLocStart(); 1742 1743 Out << S->getStmtClassName() << ' ' << (void*) S << ' '; 1744 LangOptions LO; // FIXME. 1745 S->printPretty(Out, 0, PrintingPolicy(LO)); 1746 1747 if (SLoc.isFileID()) { 1748 Out << "\\lline=" 1749 << GraphPrintSourceManager->getExpansionLineNumber(SLoc) 1750 << " col=" 1751 << GraphPrintSourceManager->getExpansionColumnNumber(SLoc) 1752 << "\\l"; 1753 } 1754 1755 if (isa<PreStmt>(Loc)) 1756 Out << "\\lPreStmt\\l;"; 1757 else if (isa<PostLoad>(Loc)) 1758 Out << "\\lPostLoad\\l;"; 1759 else if (isa<PostStore>(Loc)) 1760 Out << "\\lPostStore\\l"; 1761 else if (isa<PostLValue>(Loc)) 1762 Out << "\\lPostLValue\\l"; 1763 1764#if 0 1765 // FIXME: Replace with a general scheme to determine 1766 // the name of the check. 1767 if (GraphPrintCheckerState->isImplicitNullDeref(N)) 1768 Out << "\\|Implicit-Null Dereference.\\l"; 1769 else if (GraphPrintCheckerState->isExplicitNullDeref(N)) 1770 Out << "\\|Explicit-Null Dereference.\\l"; 1771 else if (GraphPrintCheckerState->isUndefDeref(N)) 1772 Out << "\\|Dereference of undefialied value.\\l"; 1773 else if (GraphPrintCheckerState->isUndefStore(N)) 1774 Out << "\\|Store to Undefined Loc."; 1775 else if (GraphPrintCheckerState->isUndefResult(N)) 1776 Out << "\\|Result of operation is undefined."; 1777 else if (GraphPrintCheckerState->isNoReturnCall(N)) 1778 Out << "\\|Call to function marked \"noreturn\"."; 1779 else if (GraphPrintCheckerState->isBadCall(N)) 1780 Out << "\\|Call to NULL/Undefined."; 1781 else if (GraphPrintCheckerState->isUndefArg(N)) 1782 Out << "\\|Argument in call is undefined"; 1783#endif 1784 1785 break; 1786 } 1787 1788 const BlockEdge &E = cast<BlockEdge>(Loc); 1789 Out << "Edge: (B" << E.getSrc()->getBlockID() << ", B" 1790 << E.getDst()->getBlockID() << ')'; 1791 1792 if (const Stmt *T = E.getSrc()->getTerminator()) { 1793 1794 SourceLocation SLoc = T->getLocStart(); 1795 1796 Out << "\\|Terminator: "; 1797 LangOptions LO; // FIXME. 1798 E.getSrc()->printTerminator(Out, LO); 1799 1800 if (SLoc.isFileID()) { 1801 Out << "\\lline=" 1802 << GraphPrintSourceManager->getExpansionLineNumber(SLoc) 1803 << " col=" 1804 << GraphPrintSourceManager->getExpansionColumnNumber(SLoc); 1805 } 1806 1807 if (isa<SwitchStmt>(T)) { 1808 const Stmt *Label = E.getDst()->getLabel(); 1809 1810 if (Label) { 1811 if (const CaseStmt *C = dyn_cast<CaseStmt>(Label)) { 1812 Out << "\\lcase "; 1813 LangOptions LO; // FIXME. 1814 C->getLHS()->printPretty(Out, 0, PrintingPolicy(LO)); 1815 1816 if (const Stmt *RHS = C->getRHS()) { 1817 Out << " .. "; 1818 RHS->printPretty(Out, 0, PrintingPolicy(LO)); 1819 } 1820 1821 Out << ":"; 1822 } 1823 else { 1824 assert (isa<DefaultStmt>(Label)); 1825 Out << "\\ldefault:"; 1826 } 1827 } 1828 else 1829 Out << "\\l(implicit) default:"; 1830 } 1831 else if (isa<IndirectGotoStmt>(T)) { 1832 // FIXME 1833 } 1834 else { 1835 Out << "\\lCondition: "; 1836 if (*E.getSrc()->succ_begin() == E.getDst()) 1837 Out << "true"; 1838 else 1839 Out << "false"; 1840 } 1841 1842 Out << "\\l"; 1843 } 1844 1845#if 0 1846 // FIXME: Replace with a general scheme to determine 1847 // the name of the check. 1848 if (GraphPrintCheckerState->isUndefControlFlow(N)) { 1849 Out << "\\|Control-flow based on\\lUndefined value.\\l"; 1850 } 1851#endif 1852 } 1853 } 1854 1855 ProgramStateRef state = N->getState(); 1856 Out << "\\|StateID: " << (void*) state.getPtr() 1857 << " NodeID: " << (void*) N << "\\|"; 1858 state->printDOT(Out); 1859 1860 Out << "\\l"; 1861 1862 if (const ProgramPointTag *tag = Loc.getTag()) { 1863 Out << "\\|Tag: " << tag->getTagDescription(); 1864 Out << "\\l"; 1865 } 1866 return Out.str(); 1867 } 1868}; 1869} // end llvm namespace 1870#endif 1871 1872#ifndef NDEBUG 1873template <typename ITERATOR> 1874ExplodedNode *GetGraphNode(ITERATOR I) { return *I; } 1875 1876template <> ExplodedNode* 1877GetGraphNode<llvm::DenseMap<ExplodedNode*, Expr*>::iterator> 1878 (llvm::DenseMap<ExplodedNode*, Expr*>::iterator I) { 1879 return I->first; 1880} 1881#endif 1882 1883void ExprEngine::ViewGraph(bool trim) { 1884#ifndef NDEBUG 1885 if (trim) { 1886 std::vector<ExplodedNode*> Src; 1887 1888 // Flush any outstanding reports to make sure we cover all the nodes. 1889 // This does not cause them to get displayed. 1890 for (BugReporter::iterator I=BR.begin(), E=BR.end(); I!=E; ++I) 1891 const_cast<BugType*>(*I)->FlushReports(BR); 1892 1893 // Iterate through the reports and get their nodes. 1894 for (BugReporter::EQClasses_iterator 1895 EI = BR.EQClasses_begin(), EE = BR.EQClasses_end(); EI != EE; ++EI) { 1896 BugReportEquivClass& EQ = *EI; 1897 const BugReport &R = **EQ.begin(); 1898 ExplodedNode *N = const_cast<ExplodedNode*>(R.getErrorNode()); 1899 if (N) Src.push_back(N); 1900 } 1901 1902 ViewGraph(&Src[0], &Src[0]+Src.size()); 1903 } 1904 else { 1905 GraphPrintCheckerState = this; 1906 GraphPrintSourceManager = &getContext().getSourceManager(); 1907 1908 llvm::ViewGraph(*G.roots_begin(), "ExprEngine"); 1909 1910 GraphPrintCheckerState = NULL; 1911 GraphPrintSourceManager = NULL; 1912 } 1913#endif 1914} 1915 1916void ExprEngine::ViewGraph(ExplodedNode** Beg, ExplodedNode** End) { 1917#ifndef NDEBUG 1918 GraphPrintCheckerState = this; 1919 GraphPrintSourceManager = &getContext().getSourceManager(); 1920 1921 std::auto_ptr<ExplodedGraph> TrimmedG(G.Trim(Beg, End).first); 1922 1923 if (!TrimmedG.get()) 1924 llvm::errs() << "warning: Trimmed ExplodedGraph is empty.\n"; 1925 else 1926 llvm::ViewGraph(*TrimmedG->roots_begin(), "TrimmedExprEngine"); 1927 1928 GraphPrintCheckerState = NULL; 1929 GraphPrintSourceManager = NULL; 1930#endif 1931} 1932