1 //= ProgramState.cpp - Path-Sensitive "State" for tracking values --*- C++ -*--= 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file implements ProgramState and ProgramStateManager. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h" 14 #include "clang/Analysis/CFG.h" 15 #include "clang/Basic/JsonSupport.h" 16 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h" 17 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" 18 #include "clang/StaticAnalyzer/Core/PathSensitive/DynamicType.h" 19 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h" 20 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h" 21 #include "llvm/Support/raw_ostream.h" 22 #include <optional> 23 24 using namespace clang; 25 using namespace ento; 26 27 namespace clang { namespace ento { 28 /// Increments the number of times this state is referenced. 29 30 void ProgramStateRetain(const ProgramState *state) { 31 ++const_cast<ProgramState*>(state)->refCount; 32 } 33 34 /// Decrement the number of times this state is referenced. 35 void ProgramStateRelease(const ProgramState *state) { 36 assert(state->refCount > 0); 37 ProgramState *s = const_cast<ProgramState*>(state); 38 if (--s->refCount == 0) { 39 ProgramStateManager &Mgr = s->getStateManager(); 40 Mgr.StateSet.RemoveNode(s); 41 s->~ProgramState(); 42 Mgr.freeStates.push_back(s); 43 } 44 } 45 }} 46 47 ProgramState::ProgramState(ProgramStateManager *mgr, const Environment& env, 48 StoreRef st, GenericDataMap gdm) 49 : stateMgr(mgr), 50 Env(env), 51 store(st.getStore()), 52 GDM(gdm), 53 refCount(0) { 54 stateMgr->getStoreManager().incrementReferenceCount(store); 55 } 56 57 ProgramState::ProgramState(const ProgramState &RHS) 58 : stateMgr(RHS.stateMgr), Env(RHS.Env), store(RHS.store), GDM(RHS.GDM), 59 PosteriorlyOverconstrained(RHS.PosteriorlyOverconstrained), refCount(0) { 60 stateMgr->getStoreManager().incrementReferenceCount(store); 61 } 62 63 ProgramState::~ProgramState() { 64 if (store) 65 stateMgr->getStoreManager().decrementReferenceCount(store); 66 } 67 68 int64_t ProgramState::getID() const { 69 return getStateManager().Alloc.identifyKnownAlignedObject<ProgramState>(this); 70 } 71 72 ProgramStateManager::ProgramStateManager(ASTContext &Ctx, 73 StoreManagerCreator CreateSMgr, 74 ConstraintManagerCreator CreateCMgr, 75 llvm::BumpPtrAllocator &alloc, 76 ExprEngine *ExprEng) 77 : Eng(ExprEng), EnvMgr(alloc), GDMFactory(alloc), 78 svalBuilder(createSimpleSValBuilder(alloc, Ctx, *this)), 79 CallEventMgr(new CallEventManager(alloc)), Alloc(alloc) { 80 StoreMgr = (*CreateSMgr)(*this); 81 ConstraintMgr = (*CreateCMgr)(*this, ExprEng); 82 } 83 84 85 ProgramStateManager::~ProgramStateManager() { 86 for (GDMContextsTy::iterator I=GDMContexts.begin(), E=GDMContexts.end(); 87 I!=E; ++I) 88 I->second.second(I->second.first); 89 } 90 91 ProgramStateRef ProgramStateManager::removeDeadBindingsFromEnvironmentAndStore( 92 ProgramStateRef state, const StackFrameContext *LCtx, 93 SymbolReaper &SymReaper) { 94 95 // This code essentially performs a "mark-and-sweep" of the VariableBindings. 96 // The roots are any Block-level exprs and Decls that our liveness algorithm 97 // tells us are live. We then see what Decls they may reference, and keep 98 // those around. This code more than likely can be made faster, and the 99 // frequency of which this method is called should be experimented with 100 // for optimum performance. 101 ProgramState NewState = *state; 102 103 NewState.Env = EnvMgr.removeDeadBindings(NewState.Env, SymReaper, state); 104 105 // Clean up the store. 106 StoreRef newStore = StoreMgr->removeDeadBindings(NewState.getStore(), LCtx, 107 SymReaper); 108 NewState.setStore(newStore); 109 SymReaper.setReapedStore(newStore); 110 111 return getPersistentState(NewState); 112 } 113 114 ProgramStateRef ProgramState::bindLoc(Loc LV, 115 SVal V, 116 const LocationContext *LCtx, 117 bool notifyChanges) const { 118 ProgramStateManager &Mgr = getStateManager(); 119 ProgramStateRef newState = makeWithStore(Mgr.StoreMgr->Bind(getStore(), 120 LV, V)); 121 const MemRegion *MR = LV.getAsRegion(); 122 if (MR && notifyChanges) 123 return Mgr.getOwningEngine().processRegionChange(newState, MR, LCtx); 124 125 return newState; 126 } 127 128 ProgramStateRef 129 ProgramState::bindDefaultInitial(SVal loc, SVal V, 130 const LocationContext *LCtx) const { 131 ProgramStateManager &Mgr = getStateManager(); 132 const MemRegion *R = loc.castAs<loc::MemRegionVal>().getRegion(); 133 const StoreRef &newStore = Mgr.StoreMgr->BindDefaultInitial(getStore(), R, V); 134 ProgramStateRef new_state = makeWithStore(newStore); 135 return Mgr.getOwningEngine().processRegionChange(new_state, R, LCtx); 136 } 137 138 ProgramStateRef 139 ProgramState::bindDefaultZero(SVal loc, const LocationContext *LCtx) const { 140 ProgramStateManager &Mgr = getStateManager(); 141 const MemRegion *R = loc.castAs<loc::MemRegionVal>().getRegion(); 142 const StoreRef &newStore = Mgr.StoreMgr->BindDefaultZero(getStore(), R); 143 ProgramStateRef new_state = makeWithStore(newStore); 144 return Mgr.getOwningEngine().processRegionChange(new_state, R, LCtx); 145 } 146 147 typedef ArrayRef<const MemRegion *> RegionList; 148 typedef ArrayRef<SVal> ValueList; 149 150 ProgramStateRef 151 ProgramState::invalidateRegions(RegionList Regions, 152 const Expr *E, unsigned Count, 153 const LocationContext *LCtx, 154 bool CausedByPointerEscape, 155 InvalidatedSymbols *IS, 156 const CallEvent *Call, 157 RegionAndSymbolInvalidationTraits *ITraits) const { 158 SmallVector<SVal, 8> Values; 159 for (const MemRegion *Reg : Regions) 160 Values.push_back(loc::MemRegionVal(Reg)); 161 162 return invalidateRegionsImpl(Values, E, Count, LCtx, CausedByPointerEscape, 163 IS, ITraits, Call); 164 } 165 166 ProgramStateRef 167 ProgramState::invalidateRegions(ValueList Values, 168 const Expr *E, unsigned Count, 169 const LocationContext *LCtx, 170 bool CausedByPointerEscape, 171 InvalidatedSymbols *IS, 172 const CallEvent *Call, 173 RegionAndSymbolInvalidationTraits *ITraits) const { 174 175 return invalidateRegionsImpl(Values, E, Count, LCtx, CausedByPointerEscape, 176 IS, ITraits, Call); 177 } 178 179 ProgramStateRef 180 ProgramState::invalidateRegionsImpl(ValueList Values, 181 const Expr *E, unsigned Count, 182 const LocationContext *LCtx, 183 bool CausedByPointerEscape, 184 InvalidatedSymbols *IS, 185 RegionAndSymbolInvalidationTraits *ITraits, 186 const CallEvent *Call) const { 187 ProgramStateManager &Mgr = getStateManager(); 188 ExprEngine &Eng = Mgr.getOwningEngine(); 189 190 InvalidatedSymbols InvalidatedSyms; 191 if (!IS) 192 IS = &InvalidatedSyms; 193 194 RegionAndSymbolInvalidationTraits ITraitsLocal; 195 if (!ITraits) 196 ITraits = &ITraitsLocal; 197 198 StoreManager::InvalidatedRegions TopLevelInvalidated; 199 StoreManager::InvalidatedRegions Invalidated; 200 const StoreRef &newStore 201 = Mgr.StoreMgr->invalidateRegions(getStore(), Values, E, Count, LCtx, Call, 202 *IS, *ITraits, &TopLevelInvalidated, 203 &Invalidated); 204 205 ProgramStateRef newState = makeWithStore(newStore); 206 207 if (CausedByPointerEscape) { 208 newState = Eng.notifyCheckersOfPointerEscape(newState, IS, 209 TopLevelInvalidated, 210 Call, 211 *ITraits); 212 } 213 214 return Eng.processRegionChanges(newState, IS, TopLevelInvalidated, 215 Invalidated, LCtx, Call); 216 } 217 218 ProgramStateRef ProgramState::killBinding(Loc LV) const { 219 Store OldStore = getStore(); 220 const StoreRef &newStore = 221 getStateManager().StoreMgr->killBinding(OldStore, LV); 222 223 if (newStore.getStore() == OldStore) 224 return this; 225 226 return makeWithStore(newStore); 227 } 228 229 ProgramStateRef 230 ProgramState::enterStackFrame(const CallEvent &Call, 231 const StackFrameContext *CalleeCtx) const { 232 const StoreRef &NewStore = 233 getStateManager().StoreMgr->enterStackFrame(getStore(), Call, CalleeCtx); 234 return makeWithStore(NewStore); 235 } 236 237 SVal ProgramState::getSelfSVal(const LocationContext *LCtx) const { 238 const ImplicitParamDecl *SelfDecl = LCtx->getSelfDecl(); 239 if (!SelfDecl) 240 return SVal(); 241 return getSVal(getRegion(SelfDecl, LCtx)); 242 } 243 244 SVal ProgramState::getSValAsScalarOrLoc(const MemRegion *R) const { 245 // We only want to do fetches from regions that we can actually bind 246 // values. For example, SymbolicRegions of type 'id<...>' cannot 247 // have direct bindings (but their can be bindings on their subregions). 248 if (!R->isBoundable()) 249 return UnknownVal(); 250 251 if (const TypedValueRegion *TR = dyn_cast<TypedValueRegion>(R)) { 252 QualType T = TR->getValueType(); 253 if (Loc::isLocType(T) || T->isIntegralOrEnumerationType()) 254 return getSVal(R); 255 } 256 257 return UnknownVal(); 258 } 259 260 SVal ProgramState::getSVal(Loc location, QualType T) const { 261 SVal V = getRawSVal(location, T); 262 263 // If 'V' is a symbolic value that is *perfectly* constrained to 264 // be a constant value, use that value instead to lessen the burden 265 // on later analysis stages (so we have less symbolic values to reason 266 // about). 267 // We only go into this branch if we can convert the APSInt value we have 268 // to the type of T, which is not always the case (e.g. for void). 269 if (!T.isNull() && (T->isIntegralOrEnumerationType() || Loc::isLocType(T))) { 270 if (SymbolRef sym = V.getAsSymbol()) { 271 if (const llvm::APSInt *Int = getStateManager() 272 .getConstraintManager() 273 .getSymVal(this, sym)) { 274 // FIXME: Because we don't correctly model (yet) sign-extension 275 // and truncation of symbolic values, we need to convert 276 // the integer value to the correct signedness and bitwidth. 277 // 278 // This shows up in the following: 279 // 280 // char foo(); 281 // unsigned x = foo(); 282 // if (x == 54) 283 // ... 284 // 285 // The symbolic value stored to 'x' is actually the conjured 286 // symbol for the call to foo(); the type of that symbol is 'char', 287 // not unsigned. 288 const llvm::APSInt &NewV = getBasicVals().Convert(T, *Int); 289 290 if (V.getAs<Loc>()) 291 return loc::ConcreteInt(NewV); 292 else 293 return nonloc::ConcreteInt(NewV); 294 } 295 } 296 } 297 298 return V; 299 } 300 301 ProgramStateRef ProgramState::BindExpr(const Stmt *S, 302 const LocationContext *LCtx, 303 SVal V, bool Invalidate) const{ 304 Environment NewEnv = 305 getStateManager().EnvMgr.bindExpr(Env, EnvironmentEntry(S, LCtx), V, 306 Invalidate); 307 if (NewEnv == Env) 308 return this; 309 310 ProgramState NewSt = *this; 311 NewSt.Env = NewEnv; 312 return getStateManager().getPersistentState(NewSt); 313 } 314 315 [[nodiscard]] std::pair<ProgramStateRef, ProgramStateRef> 316 ProgramState::assumeInBoundDual(DefinedOrUnknownSVal Idx, 317 DefinedOrUnknownSVal UpperBound, 318 QualType indexTy) const { 319 if (Idx.isUnknown() || UpperBound.isUnknown()) 320 return {this, this}; 321 322 // Build an expression for 0 <= Idx < UpperBound. 323 // This is the same as Idx + MIN < UpperBound + MIN, if overflow is allowed. 324 // FIXME: This should probably be part of SValBuilder. 325 ProgramStateManager &SM = getStateManager(); 326 SValBuilder &svalBuilder = SM.getSValBuilder(); 327 ASTContext &Ctx = svalBuilder.getContext(); 328 329 // Get the offset: the minimum value of the array index type. 330 BasicValueFactory &BVF = svalBuilder.getBasicValueFactory(); 331 if (indexTy.isNull()) 332 indexTy = svalBuilder.getArrayIndexType(); 333 nonloc::ConcreteInt Min(BVF.getMinValue(indexTy)); 334 335 // Adjust the index. 336 SVal newIdx = svalBuilder.evalBinOpNN(this, BO_Add, 337 Idx.castAs<NonLoc>(), Min, indexTy); 338 if (newIdx.isUnknownOrUndef()) 339 return {this, this}; 340 341 // Adjust the upper bound. 342 SVal newBound = 343 svalBuilder.evalBinOpNN(this, BO_Add, UpperBound.castAs<NonLoc>(), 344 Min, indexTy); 345 346 if (newBound.isUnknownOrUndef()) 347 return {this, this}; 348 349 // Build the actual comparison. 350 SVal inBound = svalBuilder.evalBinOpNN(this, BO_LT, newIdx.castAs<NonLoc>(), 351 newBound.castAs<NonLoc>(), Ctx.IntTy); 352 if (inBound.isUnknownOrUndef()) 353 return {this, this}; 354 355 // Finally, let the constraint manager take care of it. 356 ConstraintManager &CM = SM.getConstraintManager(); 357 return CM.assumeDual(this, inBound.castAs<DefinedSVal>()); 358 } 359 360 ProgramStateRef ProgramState::assumeInBound(DefinedOrUnknownSVal Idx, 361 DefinedOrUnknownSVal UpperBound, 362 bool Assumption, 363 QualType indexTy) const { 364 std::pair<ProgramStateRef, ProgramStateRef> R = 365 assumeInBoundDual(Idx, UpperBound, indexTy); 366 return Assumption ? R.first : R.second; 367 } 368 369 ConditionTruthVal ProgramState::isNonNull(SVal V) const { 370 ConditionTruthVal IsNull = isNull(V); 371 if (IsNull.isUnderconstrained()) 372 return IsNull; 373 return ConditionTruthVal(!IsNull.getValue()); 374 } 375 376 ConditionTruthVal ProgramState::areEqual(SVal Lhs, SVal Rhs) const { 377 return stateMgr->getSValBuilder().areEqual(this, Lhs, Rhs); 378 } 379 380 ConditionTruthVal ProgramState::isNull(SVal V) const { 381 if (V.isZeroConstant()) 382 return true; 383 384 if (V.isConstant()) 385 return false; 386 387 SymbolRef Sym = V.getAsSymbol(/* IncludeBaseRegion */ true); 388 if (!Sym) 389 return ConditionTruthVal(); 390 391 return getStateManager().ConstraintMgr->isNull(this, Sym); 392 } 393 394 ProgramStateRef ProgramStateManager::getInitialState(const LocationContext *InitLoc) { 395 ProgramState State(this, 396 EnvMgr.getInitialEnvironment(), 397 StoreMgr->getInitialStore(InitLoc), 398 GDMFactory.getEmptyMap()); 399 400 return getPersistentState(State); 401 } 402 403 ProgramStateRef ProgramStateManager::getPersistentStateWithGDM( 404 ProgramStateRef FromState, 405 ProgramStateRef GDMState) { 406 ProgramState NewState(*FromState); 407 NewState.GDM = GDMState->GDM; 408 return getPersistentState(NewState); 409 } 410 411 ProgramStateRef ProgramStateManager::getPersistentState(ProgramState &State) { 412 413 llvm::FoldingSetNodeID ID; 414 State.Profile(ID); 415 void *InsertPos; 416 417 if (ProgramState *I = StateSet.FindNodeOrInsertPos(ID, InsertPos)) 418 return I; 419 420 ProgramState *newState = nullptr; 421 if (!freeStates.empty()) { 422 newState = freeStates.back(); 423 freeStates.pop_back(); 424 } 425 else { 426 newState = Alloc.Allocate<ProgramState>(); 427 } 428 new (newState) ProgramState(State); 429 StateSet.InsertNode(newState, InsertPos); 430 return newState; 431 } 432 433 ProgramStateRef ProgramState::makeWithStore(const StoreRef &store) const { 434 ProgramState NewSt(*this); 435 NewSt.setStore(store); 436 return getStateManager().getPersistentState(NewSt); 437 } 438 439 ProgramStateRef ProgramState::cloneAsPosteriorlyOverconstrained() const { 440 ProgramState NewSt(*this); 441 NewSt.PosteriorlyOverconstrained = true; 442 return getStateManager().getPersistentState(NewSt); 443 } 444 445 void ProgramState::setStore(const StoreRef &newStore) { 446 Store newStoreStore = newStore.getStore(); 447 if (newStoreStore) 448 stateMgr->getStoreManager().incrementReferenceCount(newStoreStore); 449 if (store) 450 stateMgr->getStoreManager().decrementReferenceCount(store); 451 store = newStoreStore; 452 } 453 454 //===----------------------------------------------------------------------===// 455 // State pretty-printing. 456 //===----------------------------------------------------------------------===// 457 458 void ProgramState::printJson(raw_ostream &Out, const LocationContext *LCtx, 459 const char *NL, unsigned int Space, 460 bool IsDot) const { 461 Indent(Out, Space, IsDot) << "\"program_state\": {" << NL; 462 ++Space; 463 464 ProgramStateManager &Mgr = getStateManager(); 465 466 // Print the store. 467 Mgr.getStoreManager().printJson(Out, getStore(), NL, Space, IsDot); 468 469 // Print out the environment. 470 Env.printJson(Out, Mgr.getContext(), LCtx, NL, Space, IsDot); 471 472 // Print out the constraints. 473 Mgr.getConstraintManager().printJson(Out, this, NL, Space, IsDot); 474 475 // Print out the tracked dynamic types. 476 printDynamicTypeInfoJson(Out, this, NL, Space, IsDot); 477 478 // Print checker-specific data. 479 Mgr.getOwningEngine().printJson(Out, this, LCtx, NL, Space, IsDot); 480 481 --Space; 482 Indent(Out, Space, IsDot) << '}'; 483 } 484 485 void ProgramState::printDOT(raw_ostream &Out, const LocationContext *LCtx, 486 unsigned int Space) const { 487 printJson(Out, LCtx, /*NL=*/"\\l", Space, /*IsDot=*/true); 488 } 489 490 LLVM_DUMP_METHOD void ProgramState::dump() const { 491 printJson(llvm::errs()); 492 } 493 494 AnalysisManager& ProgramState::getAnalysisManager() const { 495 return stateMgr->getOwningEngine().getAnalysisManager(); 496 } 497 498 //===----------------------------------------------------------------------===// 499 // Generic Data Map. 500 //===----------------------------------------------------------------------===// 501 502 void *const* ProgramState::FindGDM(void *K) const { 503 return GDM.lookup(K); 504 } 505 506 void* 507 ProgramStateManager::FindGDMContext(void *K, 508 void *(*CreateContext)(llvm::BumpPtrAllocator&), 509 void (*DeleteContext)(void*)) { 510 511 std::pair<void*, void (*)(void*)>& p = GDMContexts[K]; 512 if (!p.first) { 513 p.first = CreateContext(Alloc); 514 p.second = DeleteContext; 515 } 516 517 return p.first; 518 } 519 520 ProgramStateRef ProgramStateManager::addGDM(ProgramStateRef St, void *Key, void *Data){ 521 ProgramState::GenericDataMap M1 = St->getGDM(); 522 ProgramState::GenericDataMap M2 = GDMFactory.add(M1, Key, Data); 523 524 if (M1 == M2) 525 return St; 526 527 ProgramState NewSt = *St; 528 NewSt.GDM = M2; 529 return getPersistentState(NewSt); 530 } 531 532 ProgramStateRef ProgramStateManager::removeGDM(ProgramStateRef state, void *Key) { 533 ProgramState::GenericDataMap OldM = state->getGDM(); 534 ProgramState::GenericDataMap NewM = GDMFactory.remove(OldM, Key); 535 536 if (NewM == OldM) 537 return state; 538 539 ProgramState NewState = *state; 540 NewState.GDM = NewM; 541 return getPersistentState(NewState); 542 } 543 544 bool ScanReachableSymbols::scan(nonloc::LazyCompoundVal val) { 545 bool wasVisited = !visited.insert(val.getCVData()).second; 546 if (wasVisited) 547 return true; 548 549 StoreManager &StoreMgr = state->getStateManager().getStoreManager(); 550 // FIXME: We don't really want to use getBaseRegion() here because pointer 551 // arithmetic doesn't apply, but scanReachableSymbols only accepts base 552 // regions right now. 553 const MemRegion *R = val.getRegion()->getBaseRegion(); 554 return StoreMgr.scanReachableSymbols(val.getStore(), R, *this); 555 } 556 557 bool ScanReachableSymbols::scan(nonloc::CompoundVal val) { 558 for (SVal V : val) 559 if (!scan(V)) 560 return false; 561 562 return true; 563 } 564 565 bool ScanReachableSymbols::scan(const SymExpr *sym) { 566 for (SymbolRef SubSym : sym->symbols()) { 567 bool wasVisited = !visited.insert(SubSym).second; 568 if (wasVisited) 569 continue; 570 571 if (!visitor.VisitSymbol(SubSym)) 572 return false; 573 } 574 575 return true; 576 } 577 578 bool ScanReachableSymbols::scan(SVal val) { 579 if (std::optional<loc::MemRegionVal> X = val.getAs<loc::MemRegionVal>()) 580 return scan(X->getRegion()); 581 582 if (std::optional<nonloc::LazyCompoundVal> X = 583 val.getAs<nonloc::LazyCompoundVal>()) 584 return scan(*X); 585 586 if (std::optional<nonloc::LocAsInteger> X = val.getAs<nonloc::LocAsInteger>()) 587 return scan(X->getLoc()); 588 589 if (SymbolRef Sym = val.getAsSymbol()) 590 return scan(Sym); 591 592 if (std::optional<nonloc::CompoundVal> X = val.getAs<nonloc::CompoundVal>()) 593 return scan(*X); 594 595 return true; 596 } 597 598 bool ScanReachableSymbols::scan(const MemRegion *R) { 599 if (isa<MemSpaceRegion>(R)) 600 return true; 601 602 bool wasVisited = !visited.insert(R).second; 603 if (wasVisited) 604 return true; 605 606 if (!visitor.VisitMemRegion(R)) 607 return false; 608 609 // If this is a symbolic region, visit the symbol for the region. 610 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) 611 if (!visitor.VisitSymbol(SR->getSymbol())) 612 return false; 613 614 // If this is a subregion, also visit the parent regions. 615 if (const SubRegion *SR = dyn_cast<SubRegion>(R)) { 616 const MemRegion *Super = SR->getSuperRegion(); 617 if (!scan(Super)) 618 return false; 619 620 // When we reach the topmost region, scan all symbols in it. 621 if (isa<MemSpaceRegion>(Super)) { 622 StoreManager &StoreMgr = state->getStateManager().getStoreManager(); 623 if (!StoreMgr.scanReachableSymbols(state->getStore(), SR, *this)) 624 return false; 625 } 626 } 627 628 // Regions captured by a block are also implicitly reachable. 629 if (const BlockDataRegion *BDR = dyn_cast<BlockDataRegion>(R)) { 630 for (auto Var : BDR->referenced_vars()) { 631 if (!scan(Var.getCapturedRegion())) 632 return false; 633 } 634 } 635 636 return true; 637 } 638 639 bool ProgramState::scanReachableSymbols(SVal val, SymbolVisitor& visitor) const { 640 ScanReachableSymbols S(this, visitor); 641 return S.scan(val); 642 } 643 644 bool ProgramState::scanReachableSymbols( 645 llvm::iterator_range<region_iterator> Reachable, 646 SymbolVisitor &visitor) const { 647 ScanReachableSymbols S(this, visitor); 648 for (const MemRegion *R : Reachable) { 649 if (!S.scan(R)) 650 return false; 651 } 652 return true; 653 } 654