clang  7.0.0svn
ExprEngineC.cpp
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1 //=-- ExprEngineC.cpp - ExprEngine support for C expressions ----*- 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 ExprEngine's support for C expressions.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/AST/ExprCXX.h"
15 #include "clang/AST/DeclCXX.h"
18 
19 using namespace clang;
20 using namespace ento;
21 using llvm::APSInt;
22 
23 /// Optionally conjure and return a symbol for offset when processing
24 /// an expression \p Expression.
25 /// If \p Other is a location, conjure a symbol for \p Symbol
26 /// (offset) if it is unknown so that memory arithmetic always
27 /// results in an ElementRegion.
28 /// \p Count The number of times the current basic block was visited.
30  SVal Symbol, SVal Other, Expr* Expression, SValBuilder &svalBuilder,
31  unsigned Count, const LocationContext *LCtx) {
32  QualType Ty = Expression->getType();
33  if (Other.getAs<Loc>() &&
35  Symbol.isUnknown()) {
36  return svalBuilder.conjureSymbolVal(Expression, LCtx, Ty, Count);
37  }
38  return Symbol;
39 }
40 
42  ExplodedNode *Pred,
43  ExplodedNodeSet &Dst) {
44 
45  Expr *LHS = B->getLHS()->IgnoreParens();
46  Expr *RHS = B->getRHS()->IgnoreParens();
47 
48  // FIXME: Prechecks eventually go in ::Visit().
49  ExplodedNodeSet CheckedSet;
50  ExplodedNodeSet Tmp2;
51  getCheckerManager().runCheckersForPreStmt(CheckedSet, Pred, B, *this);
52 
53  // With both the LHS and RHS evaluated, process the operation itself.
54  for (ExplodedNodeSet::iterator it=CheckedSet.begin(), ei=CheckedSet.end();
55  it != ei; ++it) {
56 
57  ProgramStateRef state = (*it)->getState();
58  const LocationContext *LCtx = (*it)->getLocationContext();
59  SVal LeftV = state->getSVal(LHS, LCtx);
60  SVal RightV = state->getSVal(RHS, LCtx);
61 
63 
64  if (Op == BO_Assign) {
65  // EXPERIMENTAL: "Conjured" symbols.
66  // FIXME: Handle structs.
67  if (RightV.isUnknown()) {
68  unsigned Count = currBldrCtx->blockCount();
69  RightV = svalBuilder.conjureSymbolVal(nullptr, B->getRHS(), LCtx,
70  Count);
71  }
72  // Simulate the effects of a "store": bind the value of the RHS
73  // to the L-Value represented by the LHS.
74  SVal ExprVal = B->isGLValue() ? LeftV : RightV;
75  evalStore(Tmp2, B, LHS, *it, state->BindExpr(B, LCtx, ExprVal),
76  LeftV, RightV);
77  continue;
78  }
79 
80  if (!B->isAssignmentOp()) {
81  StmtNodeBuilder Bldr(*it, Tmp2, *currBldrCtx);
82 
83  if (B->isAdditiveOp()) {
84  // TODO: This can be removed after we enable history tracking with
85  // SymSymExpr.
86  unsigned Count = currBldrCtx->blockCount();
88  RightV, LeftV, RHS, svalBuilder, Count, LCtx);
90  LeftV, RightV, LHS, svalBuilder, Count, LCtx);
91  }
92 
93  // Although we don't yet model pointers-to-members, we do need to make
94  // sure that the members of temporaries have a valid 'this' pointer for
95  // other checks.
96  if (B->getOpcode() == BO_PtrMemD)
97  state = createTemporaryRegionIfNeeded(state, LCtx, LHS);
98 
99  // Process non-assignments except commas or short-circuited
100  // logical expressions (LAnd and LOr).
101  SVal Result = evalBinOp(state, Op, LeftV, RightV, B->getType());
102  if (!Result.isUnknown()) {
103  state = state->BindExpr(B, LCtx, Result);
104  }
105 
106  Bldr.generateNode(B, *it, state);
107  continue;
108  }
109 
110  assert (B->isCompoundAssignmentOp());
111 
112  switch (Op) {
113  default:
114  llvm_unreachable("Invalid opcode for compound assignment.");
115  case BO_MulAssign: Op = BO_Mul; break;
116  case BO_DivAssign: Op = BO_Div; break;
117  case BO_RemAssign: Op = BO_Rem; break;
118  case BO_AddAssign: Op = BO_Add; break;
119  case BO_SubAssign: Op = BO_Sub; break;
120  case BO_ShlAssign: Op = BO_Shl; break;
121  case BO_ShrAssign: Op = BO_Shr; break;
122  case BO_AndAssign: Op = BO_And; break;
123  case BO_XorAssign: Op = BO_Xor; break;
124  case BO_OrAssign: Op = BO_Or; break;
125  }
126 
127  // Perform a load (the LHS). This performs the checks for
128  // null dereferences, and so on.
129  ExplodedNodeSet Tmp;
130  SVal location = LeftV;
131  evalLoad(Tmp, B, LHS, *it, state, location);
132 
133  for (ExplodedNodeSet::iterator I = Tmp.begin(), E = Tmp.end(); I != E;
134  ++I) {
135 
136  state = (*I)->getState();
137  const LocationContext *LCtx = (*I)->getLocationContext();
138  SVal V = state->getSVal(LHS, LCtx);
139 
140  // Get the computation type.
141  QualType CTy =
142  cast<CompoundAssignOperator>(B)->getComputationResultType();
143  CTy = getContext().getCanonicalType(CTy);
144 
145  QualType CLHSTy =
146  cast<CompoundAssignOperator>(B)->getComputationLHSType();
147  CLHSTy = getContext().getCanonicalType(CLHSTy);
148 
150 
151  // Promote LHS.
152  V = svalBuilder.evalCast(V, CLHSTy, LTy);
153 
154  // Compute the result of the operation.
155  SVal Result = svalBuilder.evalCast(evalBinOp(state, Op, V, RightV, CTy),
156  B->getType(), CTy);
157 
158  // EXPERIMENTAL: "Conjured" symbols.
159  // FIXME: Handle structs.
160 
161  SVal LHSVal;
162 
163  if (Result.isUnknown()) {
164  // The symbolic value is actually for the type of the left-hand side
165  // expression, not the computation type, as this is the value the
166  // LValue on the LHS will bind to.
167  LHSVal = svalBuilder.conjureSymbolVal(nullptr, B->getRHS(), LCtx, LTy,
168  currBldrCtx->blockCount());
169  // However, we need to convert the symbol to the computation type.
170  Result = svalBuilder.evalCast(LHSVal, CTy, LTy);
171  }
172  else {
173  // The left-hand side may bind to a different value then the
174  // computation type.
175  LHSVal = svalBuilder.evalCast(Result, LTy, CTy);
176  }
177 
178  // In C++, assignment and compound assignment operators return an
179  // lvalue.
180  if (B->isGLValue())
181  state = state->BindExpr(B, LCtx, location);
182  else
183  state = state->BindExpr(B, LCtx, Result);
184 
185  evalStore(Tmp2, B, LHS, *I, state, location, LHSVal);
186  }
187  }
188 
189  // FIXME: postvisits eventually go in ::Visit()
190  getCheckerManager().runCheckersForPostStmt(Dst, Tmp2, B, *this);
191 }
192 
194  ExplodedNodeSet &Dst) {
195 
197 
198  const BlockDecl *BD = BE->getBlockDecl();
199  // Get the value of the block itself.
200  SVal V = svalBuilder.getBlockPointer(BD, T,
201  Pred->getLocationContext(),
202  currBldrCtx->blockCount());
203 
204  ProgramStateRef State = Pred->getState();
205 
206  // If we created a new MemRegion for the block, we should explicitly bind
207  // the captured variables.
208  if (const BlockDataRegion *BDR =
209  dyn_cast_or_null<BlockDataRegion>(V.getAsRegion())) {
210 
211  BlockDataRegion::referenced_vars_iterator I = BDR->referenced_vars_begin(),
212  E = BDR->referenced_vars_end();
213 
214  auto CI = BD->capture_begin();
215  auto CE = BD->capture_end();
216  for (; I != E; ++I) {
217  const VarRegion *capturedR = I.getCapturedRegion();
218  const VarRegion *originalR = I.getOriginalRegion();
219 
220  // If the capture had a copy expression, use the result of evaluating
221  // that expression, otherwise use the original value.
222  // We rely on the invariant that the block declaration's capture variables
223  // are a prefix of the BlockDataRegion's referenced vars (which may include
224  // referenced globals, etc.) to enable fast lookup of the capture for a
225  // given referenced var.
226  const Expr *copyExpr = nullptr;
227  if (CI != CE) {
228  assert(CI->getVariable() == capturedR->getDecl());
229  copyExpr = CI->getCopyExpr();
230  CI++;
231  }
232 
233  if (capturedR != originalR) {
234  SVal originalV;
235  const LocationContext *LCtx = Pred->getLocationContext();
236  if (copyExpr) {
237  originalV = State->getSVal(copyExpr, LCtx);
238  } else {
239  originalV = State->getSVal(loc::MemRegionVal(originalR));
240  }
241  State = State->bindLoc(loc::MemRegionVal(capturedR), originalV, LCtx);
242  }
243  }
244  }
245 
246  ExplodedNodeSet Tmp;
247  StmtNodeBuilder Bldr(Pred, Tmp, *currBldrCtx);
248  Bldr.generateNode(BE, Pred,
249  State->BindExpr(BE, Pred->getLocationContext(), V),
251 
252  // FIXME: Move all post/pre visits to ::Visit().
253  getCheckerManager().runCheckersForPostStmt(Dst, Tmp, BE, *this);
254 }
255 
257  ProgramStateRef state, const Expr* Ex, const LocationContext* LCtx,
258  QualType T, QualType ExTy, const CastExpr* CastE, StmtNodeBuilder& Bldr,
259  ExplodedNode* Pred) {
260  if (T->isLValueReferenceType()) {
261  assert(!CastE->getType()->isLValueReferenceType());
262  ExTy = getContext().getLValueReferenceType(ExTy);
263  } else if (T->isRValueReferenceType()) {
264  assert(!CastE->getType()->isRValueReferenceType());
265  ExTy = getContext().getRValueReferenceType(ExTy);
266  }
267  // Delegate to SValBuilder to process.
268  SVal OrigV = state->getSVal(Ex, LCtx);
269  SVal V = svalBuilder.evalCast(OrigV, T, ExTy);
270  // Negate the result if we're treating the boolean as a signed i1
271  if (CastE->getCastKind() == CK_BooleanToSignedIntegral)
272  V = evalMinus(V);
273  state = state->BindExpr(CastE, LCtx, V);
274  if (V.isUnknown() && !OrigV.isUnknown()) {
275  state = escapeValue(state, OrigV, PSK_EscapeOther);
276  }
277  Bldr.generateNode(CastE, Pred, state);
278 
279  return state;
280 }
281 
283  ProgramStateRef state, const LocationContext* LCtx, const CastExpr* CastE,
284  StmtNodeBuilder &Bldr, ExplodedNode* Pred) {
285  // Recover some path sensitivity by conjuring a new value.
286  QualType resultType = CastE->getType();
287  if (CastE->isGLValue())
288  resultType = getContext().getPointerType(resultType);
289  SVal result = svalBuilder.conjureSymbolVal(nullptr, CastE, LCtx,
290  resultType,
291  currBldrCtx->blockCount());
292  state = state->BindExpr(CastE, LCtx, result);
293  Bldr.generateNode(CastE, Pred, state);
294 
295  return state;
296 }
297 
298 void ExprEngine::VisitCast(const CastExpr *CastE, const Expr *Ex,
299  ExplodedNode *Pred, ExplodedNodeSet &Dst) {
300 
301  ExplodedNodeSet dstPreStmt;
302  getCheckerManager().runCheckersForPreStmt(dstPreStmt, Pred, CastE, *this);
303 
304  if (CastE->getCastKind() == CK_LValueToRValue) {
305  for (ExplodedNodeSet::iterator I = dstPreStmt.begin(), E = dstPreStmt.end();
306  I!=E; ++I) {
307  ExplodedNode *subExprNode = *I;
308  ProgramStateRef state = subExprNode->getState();
309  const LocationContext *LCtx = subExprNode->getLocationContext();
310  evalLoad(Dst, CastE, CastE, subExprNode, state, state->getSVal(Ex, LCtx));
311  }
312  return;
313  }
314 
315  // All other casts.
316  QualType T = CastE->getType();
317  QualType ExTy = Ex->getType();
318 
319  if (const ExplicitCastExpr *ExCast=dyn_cast_or_null<ExplicitCastExpr>(CastE))
320  T = ExCast->getTypeAsWritten();
321 
322  StmtNodeBuilder Bldr(dstPreStmt, Dst, *currBldrCtx);
323  for (ExplodedNodeSet::iterator I = dstPreStmt.begin(), E = dstPreStmt.end();
324  I != E; ++I) {
325 
326  Pred = *I;
327  ProgramStateRef state = Pred->getState();
328  const LocationContext *LCtx = Pred->getLocationContext();
329 
330  switch (CastE->getCastKind()) {
331  case CK_LValueToRValue:
332  llvm_unreachable("LValueToRValue casts handled earlier.");
333  case CK_ToVoid:
334  continue;
335  // The analyzer doesn't do anything special with these casts,
336  // since it understands retain/release semantics already.
337  case CK_ARCProduceObject:
338  case CK_ARCConsumeObject:
339  case CK_ARCReclaimReturnedObject:
340  case CK_ARCExtendBlockObject: // Fall-through.
341  case CK_CopyAndAutoreleaseBlockObject:
342  // The analyser can ignore atomic casts for now, although some future
343  // checkers may want to make certain that you're not modifying the same
344  // value through atomic and nonatomic pointers.
345  case CK_AtomicToNonAtomic:
346  case CK_NonAtomicToAtomic:
347  // True no-ops.
348  case CK_NoOp:
349  case CK_ConstructorConversion:
350  case CK_UserDefinedConversion:
351  case CK_FunctionToPointerDecay:
352  case CK_BuiltinFnToFnPtr: {
353  // Copy the SVal of Ex to CastE.
354  ProgramStateRef state = Pred->getState();
355  const LocationContext *LCtx = Pred->getLocationContext();
356  SVal V = state->getSVal(Ex, LCtx);
357  state = state->BindExpr(CastE, LCtx, V);
358  Bldr.generateNode(CastE, Pred, state);
359  continue;
360  }
361  case CK_MemberPointerToBoolean:
362  case CK_PointerToBoolean: {
363  SVal V = state->getSVal(Ex, LCtx);
364  auto PTMSV = V.getAs<nonloc::PointerToMember>();
365  if (PTMSV)
366  V = svalBuilder.makeTruthVal(!PTMSV->isNullMemberPointer(), ExTy);
367  if (V.isUndef() || PTMSV) {
368  state = state->BindExpr(CastE, LCtx, V);
369  Bldr.generateNode(CastE, Pred, state);
370  continue;
371  }
372  // Explicitly proceed with default handler for this case cascade.
373  state =
374  handleLValueBitCast(state, Ex, LCtx, T, ExTy, CastE, Bldr, Pred);
375  continue;
376  }
377  case CK_Dependent:
378  case CK_ArrayToPointerDecay:
379  case CK_BitCast:
380  case CK_AddressSpaceConversion:
381  case CK_BooleanToSignedIntegral:
382  case CK_NullToPointer:
383  case CK_IntegralToPointer:
384  case CK_PointerToIntegral: {
385  SVal V = state->getSVal(Ex, LCtx);
386  if (V.getAs<nonloc::PointerToMember>()) {
387  state = state->BindExpr(CastE, LCtx, UnknownVal());
388  Bldr.generateNode(CastE, Pred, state);
389  continue;
390  }
391  // Explicitly proceed with default handler for this case cascade.
392  state =
393  handleLValueBitCast(state, Ex, LCtx, T, ExTy, CastE, Bldr, Pred);
394  continue;
395  }
396  case CK_IntegralToBoolean:
397  case CK_IntegralToFloating:
398  case CK_FloatingToIntegral:
399  case CK_FloatingToBoolean:
400  case CK_FloatingCast:
401  case CK_FloatingRealToComplex:
402  case CK_FloatingComplexToReal:
403  case CK_FloatingComplexToBoolean:
404  case CK_FloatingComplexCast:
405  case CK_FloatingComplexToIntegralComplex:
406  case CK_IntegralRealToComplex:
407  case CK_IntegralComplexToReal:
408  case CK_IntegralComplexToBoolean:
409  case CK_IntegralComplexCast:
410  case CK_IntegralComplexToFloatingComplex:
411  case CK_CPointerToObjCPointerCast:
412  case CK_BlockPointerToObjCPointerCast:
413  case CK_AnyPointerToBlockPointerCast:
414  case CK_ObjCObjectLValueCast:
415  case CK_ZeroToOCLEvent:
416  case CK_ZeroToOCLQueue:
417  case CK_IntToOCLSampler:
418  case CK_LValueBitCast: {
419  state =
420  handleLValueBitCast(state, Ex, LCtx, T, ExTy, CastE, Bldr, Pred);
421  continue;
422  }
423  case CK_IntegralCast: {
424  // Delegate to SValBuilder to process.
425  SVal V = state->getSVal(Ex, LCtx);
426  V = svalBuilder.evalIntegralCast(state, V, T, ExTy);
427  state = state->BindExpr(CastE, LCtx, V);
428  Bldr.generateNode(CastE, Pred, state);
429  continue;
430  }
431  case CK_DerivedToBase:
432  case CK_UncheckedDerivedToBase: {
433  // For DerivedToBase cast, delegate to the store manager.
434  SVal val = state->getSVal(Ex, LCtx);
435  val = getStoreManager().evalDerivedToBase(val, CastE);
436  state = state->BindExpr(CastE, LCtx, val);
437  Bldr.generateNode(CastE, Pred, state);
438  continue;
439  }
440  // Handle C++ dyn_cast.
441  case CK_Dynamic: {
442  SVal val = state->getSVal(Ex, LCtx);
443 
444  // Compute the type of the result.
445  QualType resultType = CastE->getType();
446  if (CastE->isGLValue())
447  resultType = getContext().getPointerType(resultType);
448 
449  bool Failed = false;
450 
451  // Check if the value being cast evaluates to 0.
452  if (val.isZeroConstant())
453  Failed = true;
454  // Else, evaluate the cast.
455  else
456  val = getStoreManager().attemptDownCast(val, T, Failed);
457 
458  if (Failed) {
459  if (T->isReferenceType()) {
460  // A bad_cast exception is thrown if input value is a reference.
461  // Currently, we model this, by generating a sink.
462  Bldr.generateSink(CastE, Pred, state);
463  continue;
464  } else {
465  // If the cast fails on a pointer, bind to 0.
466  state = state->BindExpr(CastE, LCtx, svalBuilder.makeNull());
467  }
468  } else {
469  // If we don't know if the cast succeeded, conjure a new symbol.
470  if (val.isUnknown()) {
471  DefinedOrUnknownSVal NewSym =
472  svalBuilder.conjureSymbolVal(nullptr, CastE, LCtx, resultType,
473  currBldrCtx->blockCount());
474  state = state->BindExpr(CastE, LCtx, NewSym);
475  } else
476  // Else, bind to the derived region value.
477  state = state->BindExpr(CastE, LCtx, val);
478  }
479  Bldr.generateNode(CastE, Pred, state);
480  continue;
481  }
482  case CK_BaseToDerived: {
483  SVal val = state->getSVal(Ex, LCtx);
484  QualType resultType = CastE->getType();
485  if (CastE->isGLValue())
486  resultType = getContext().getPointerType(resultType);
487 
488  bool Failed = false;
489 
490  if (!val.isConstant()) {
491  val = getStoreManager().attemptDownCast(val, T, Failed);
492  }
493 
494  // Failed to cast or the result is unknown, fall back to conservative.
495  if (Failed || val.isUnknown()) {
496  val =
497  svalBuilder.conjureSymbolVal(nullptr, CastE, LCtx, resultType,
498  currBldrCtx->blockCount());
499  }
500  state = state->BindExpr(CastE, LCtx, val);
501  Bldr.generateNode(CastE, Pred, state);
502  continue;
503  }
504  case CK_NullToMemberPointer: {
505  SVal V = svalBuilder.getMemberPointer(nullptr);
506  state = state->BindExpr(CastE, LCtx, V);
507  Bldr.generateNode(CastE, Pred, state);
508  continue;
509  }
510  case CK_DerivedToBaseMemberPointer:
511  case CK_BaseToDerivedMemberPointer:
512  case CK_ReinterpretMemberPointer: {
513  SVal V = state->getSVal(Ex, LCtx);
514  if (auto PTMSV = V.getAs<nonloc::PointerToMember>()) {
515  SVal CastedPTMSV = svalBuilder.makePointerToMember(
516  getBasicVals().accumCXXBase(
517  llvm::make_range<CastExpr::path_const_iterator>(
518  CastE->path_begin(), CastE->path_end()), *PTMSV));
519  state = state->BindExpr(CastE, LCtx, CastedPTMSV);
520  Bldr.generateNode(CastE, Pred, state);
521  continue;
522  }
523  // Explicitly proceed with default handler for this case cascade.
524  state = handleLVectorSplat(state, LCtx, CastE, Bldr, Pred);
525  continue;
526  }
527  // Various C++ casts that are not handled yet.
528  case CK_ToUnion:
529  case CK_VectorSplat: {
530  state = handleLVectorSplat(state, LCtx, CastE, Bldr, Pred);
531  continue;
532  }
533  }
534  }
535 }
536 
538  ExplodedNode *Pred,
539  ExplodedNodeSet &Dst) {
540  StmtNodeBuilder B(Pred, Dst, *currBldrCtx);
541 
542  ProgramStateRef State = Pred->getState();
543  const LocationContext *LCtx = Pred->getLocationContext();
544 
545  const Expr *Init = CL->getInitializer();
546  SVal V = State->getSVal(CL->getInitializer(), LCtx);
547 
548  if (isa<CXXConstructExpr>(Init) || isa<CXXStdInitializerListExpr>(Init)) {
549  // No work needed. Just pass the value up to this expression.
550  } else {
551  assert(isa<InitListExpr>(Init));
552  Loc CLLoc = State->getLValue(CL, LCtx);
553  State = State->bindLoc(CLLoc, V, LCtx);
554 
555  if (CL->isGLValue())
556  V = CLLoc;
557  }
558 
559  B.generateNode(CL, Pred, State->BindExpr(CL, LCtx, V));
560 }
561 
563  ExplodedNodeSet &Dst) {
564  // Assumption: The CFG has one DeclStmt per Decl.
565  const VarDecl *VD = dyn_cast_or_null<VarDecl>(*DS->decl_begin());
566 
567  if (!VD) {
568  //TODO:AZ: remove explicit insertion after refactoring is done.
569  Dst.insert(Pred);
570  return;
571  }
572 
573  // FIXME: all pre/post visits should eventually be handled by ::Visit().
574  ExplodedNodeSet dstPreVisit;
575  getCheckerManager().runCheckersForPreStmt(dstPreVisit, Pred, DS, *this);
576 
577  ExplodedNodeSet dstEvaluated;
578  StmtNodeBuilder B(dstPreVisit, dstEvaluated, *currBldrCtx);
579  for (ExplodedNodeSet::iterator I = dstPreVisit.begin(), E = dstPreVisit.end();
580  I!=E; ++I) {
581  ExplodedNode *N = *I;
583  const LocationContext *LC = N->getLocationContext();
584 
585  // Decls without InitExpr are not initialized explicitly.
586  if (const Expr *InitEx = VD->getInit()) {
587 
588  // Note in the state that the initialization has occurred.
589  ExplodedNode *UpdatedN = N;
590  SVal InitVal = state->getSVal(InitEx, LC);
591 
592  assert(DS->isSingleDecl());
593  if (getObjectUnderConstruction(state, DS, LC)) {
594  state = finishObjectConstruction(state, DS, LC);
595  // We constructed the object directly in the variable.
596  // No need to bind anything.
597  B.generateNode(DS, UpdatedN, state);
598  } else {
599  // Recover some path-sensitivity if a scalar value evaluated to
600  // UnknownVal.
601  if (InitVal.isUnknown()) {
602  QualType Ty = InitEx->getType();
603  if (InitEx->isGLValue()) {
604  Ty = getContext().getPointerType(Ty);
605  }
606 
607  InitVal = svalBuilder.conjureSymbolVal(nullptr, InitEx, LC, Ty,
608  currBldrCtx->blockCount());
609  }
610 
611 
612  B.takeNodes(UpdatedN);
613  ExplodedNodeSet Dst2;
614  evalBind(Dst2, DS, UpdatedN, state->getLValue(VD, LC), InitVal, true);
615  B.addNodes(Dst2);
616  }
617  }
618  else {
619  B.generateNode(DS, N, state);
620  }
621  }
622 
623  getCheckerManager().runCheckersForPostStmt(Dst, B.getResults(), DS, *this);
624 }
625 
627  ExplodedNodeSet &Dst) {
628  assert(B->getOpcode() == BO_LAnd ||
629  B->getOpcode() == BO_LOr);
630 
631  StmtNodeBuilder Bldr(Pred, Dst, *currBldrCtx);
632  ProgramStateRef state = Pred->getState();
633 
634  if (B->getType()->isVectorType()) {
635  // FIXME: We do not model vector arithmetic yet. When adding support for
636  // that, note that the CFG-based reasoning below does not apply, because
637  // logical operators on vectors are not short-circuit. Currently they are
638  // modeled as short-circuit in Clang CFG but this is incorrect.
639  // Do not set the value for the expression. It'd be UnknownVal by default.
640  Bldr.generateNode(B, Pred, state);
641  return;
642  }
643 
644  ExplodedNode *N = Pred;
645  while (!N->getLocation().getAs<BlockEntrance>()) {
646  ProgramPoint P = N->getLocation();
647  assert(P.getAs<PreStmt>()|| P.getAs<PreStmtPurgeDeadSymbols>());
648  (void) P;
649  assert(N->pred_size() == 1);
650  N = *N->pred_begin();
651  }
652  assert(N->pred_size() == 1);
653  N = *N->pred_begin();
654  BlockEdge BE = N->getLocation().castAs<BlockEdge>();
655  SVal X;
656 
657  // Determine the value of the expression by introspecting how we
658  // got this location in the CFG. This requires looking at the previous
659  // block we were in and what kind of control-flow transfer was involved.
660  const CFGBlock *SrcBlock = BE.getSrc();
661  // The only terminator (if there is one) that makes sense is a logical op.
662  CFGTerminator T = SrcBlock->getTerminator();
663  if (const BinaryOperator *Term = cast_or_null<BinaryOperator>(T.getStmt())) {
664  (void) Term;
665  assert(Term->isLogicalOp());
666  assert(SrcBlock->succ_size() == 2);
667  // Did we take the true or false branch?
668  unsigned constant = (*SrcBlock->succ_begin() == BE.getDst()) ? 1 : 0;
669  X = svalBuilder.makeIntVal(constant, B->getType());
670  }
671  else {
672  // If there is no terminator, by construction the last statement
673  // in SrcBlock is the value of the enclosing expression.
674  // However, we still need to constrain that value to be 0 or 1.
675  assert(!SrcBlock->empty());
676  CFGStmt Elem = SrcBlock->rbegin()->castAs<CFGStmt>();
677  const Expr *RHS = cast<Expr>(Elem.getStmt());
678  SVal RHSVal = N->getState()->getSVal(RHS, Pred->getLocationContext());
679 
680  if (RHSVal.isUndef()) {
681  X = RHSVal;
682  } else {
683  // We evaluate "RHSVal != 0" expression which result in 0 if the value is
684  // known to be false, 1 if the value is known to be true and a new symbol
685  // when the assumption is unknown.
687  X = evalBinOp(N->getState(), BO_NE,
688  svalBuilder.evalCast(RHSVal, B->getType(), RHS->getType()),
689  Zero, B->getType());
690  }
691  }
692  Bldr.generateNode(B, Pred, state->BindExpr(B, Pred->getLocationContext(), X));
693 }
694 
696  ExplodedNode *Pred,
697  ExplodedNodeSet &Dst) {
698  StmtNodeBuilder B(Pred, Dst, *currBldrCtx);
699 
700  ProgramStateRef state = Pred->getState();
701  const LocationContext *LCtx = Pred->getLocationContext();
703  unsigned NumInitElements = IE->getNumInits();
704 
705  if (!IE->isGLValue() &&
706  (T->isArrayType() || T->isRecordType() || T->isVectorType() ||
707  T->isAnyComplexType())) {
708  llvm::ImmutableList<SVal> vals = getBasicVals().getEmptySValList();
709 
710  // Handle base case where the initializer has no elements.
711  // e.g: static int* myArray[] = {};
712  if (NumInitElements == 0) {
713  SVal V = svalBuilder.makeCompoundVal(T, vals);
714  B.generateNode(IE, Pred, state->BindExpr(IE, LCtx, V));
715  return;
716  }
717 
719  ei = IE->rend(); it != ei; ++it) {
720  SVal V = state->getSVal(cast<Expr>(*it), LCtx);
721  vals = getBasicVals().prependSVal(V, vals);
722  }
723 
724  B.generateNode(IE, Pred,
725  state->BindExpr(IE, LCtx,
726  svalBuilder.makeCompoundVal(T, vals)));
727  return;
728  }
729 
730  // Handle scalars: int{5} and int{} and GLvalues.
731  // Note, if the InitListExpr is a GLvalue, it means that there is an address
732  // representing it, so it must have a single init element.
733  assert(NumInitElements <= 1);
734 
735  SVal V;
736  if (NumInitElements == 0)
737  V = getSValBuilder().makeZeroVal(T);
738  else
739  V = state->getSVal(IE->getInit(0), LCtx);
740 
741  B.generateNode(IE, Pred, state->BindExpr(IE, LCtx, V));
742 }
743 
745  const Expr *L,
746  const Expr *R,
747  ExplodedNode *Pred,
748  ExplodedNodeSet &Dst) {
749  assert(L && R);
750 
751  StmtNodeBuilder B(Pred, Dst, *currBldrCtx);
752  ProgramStateRef state = Pred->getState();
753  const LocationContext *LCtx = Pred->getLocationContext();
754  const CFGBlock *SrcBlock = nullptr;
755 
756  // Find the predecessor block.
757  ProgramStateRef SrcState = state;
758  for (const ExplodedNode *N = Pred ; N ; N = *N->pred_begin()) {
759  ProgramPoint PP = N->getLocation();
760  if (PP.getAs<PreStmtPurgeDeadSymbols>() || PP.getAs<BlockEntrance>()) {
761  // If the state N has multiple predecessors P, it means that successors
762  // of P are all equivalent.
763  // In turn, that means that all nodes at P are equivalent in terms
764  // of observable behavior at N, and we can follow any of them.
765  // FIXME: a more robust solution which does not walk up the tree.
766  continue;
767  }
768  SrcBlock = PP.castAs<BlockEdge>().getSrc();
769  SrcState = N->getState();
770  break;
771  }
772 
773  assert(SrcBlock && "missing function entry");
774 
775  // Find the last expression in the predecessor block. That is the
776  // expression that is used for the value of the ternary expression.
777  bool hasValue = false;
778  SVal V;
779 
780  for (CFGElement CE : llvm::reverse(*SrcBlock)) {
781  if (Optional<CFGStmt> CS = CE.getAs<CFGStmt>()) {
782  const Expr *ValEx = cast<Expr>(CS->getStmt());
783  ValEx = ValEx->IgnoreParens();
784 
785  // For GNU extension '?:' operator, the left hand side will be an
786  // OpaqueValueExpr, so get the underlying expression.
787  if (const OpaqueValueExpr *OpaqueEx = dyn_cast<OpaqueValueExpr>(L))
788  L = OpaqueEx->getSourceExpr();
789 
790  // If the last expression in the predecessor block matches true or false
791  // subexpression, get its the value.
792  if (ValEx == L->IgnoreParens() || ValEx == R->IgnoreParens()) {
793  hasValue = true;
794  V = SrcState->getSVal(ValEx, LCtx);
795  }
796  break;
797  }
798  }
799 
800  if (!hasValue)
801  V = svalBuilder.conjureSymbolVal(nullptr, Ex, LCtx,
802  currBldrCtx->blockCount());
803 
804  // Generate a new node with the binding from the appropriate path.
805  B.generateNode(Ex, Pred, state->BindExpr(Ex, LCtx, V, true));
806 }
807 
808 void ExprEngine::
810  ExplodedNode *Pred, ExplodedNodeSet &Dst) {
811  StmtNodeBuilder B(Pred, Dst, *currBldrCtx);
812  APSInt IV;
813  if (OOE->EvaluateAsInt(IV, getContext())) {
814  assert(IV.getBitWidth() == getContext().getTypeSize(OOE->getType()));
815  assert(OOE->getType()->isBuiltinType());
816  assert(OOE->getType()->getAs<BuiltinType>()->isInteger());
817  assert(IV.isSigned() == OOE->getType()->isSignedIntegerType());
818  SVal X = svalBuilder.makeIntVal(IV);
819  B.generateNode(OOE, Pred,
820  Pred->getState()->BindExpr(OOE, Pred->getLocationContext(),
821  X));
822  }
823  // FIXME: Handle the case where __builtin_offsetof is not a constant.
824 }
825 
826 
827 void ExprEngine::
829  ExplodedNode *Pred,
830  ExplodedNodeSet &Dst) {
831  // FIXME: Prechecks eventually go in ::Visit().
832  ExplodedNodeSet CheckedSet;
833  getCheckerManager().runCheckersForPreStmt(CheckedSet, Pred, Ex, *this);
834 
835  ExplodedNodeSet EvalSet;
836  StmtNodeBuilder Bldr(CheckedSet, EvalSet, *currBldrCtx);
837 
838  QualType T = Ex->getTypeOfArgument();
839 
840  for (ExplodedNodeSet::iterator I = CheckedSet.begin(), E = CheckedSet.end();
841  I != E; ++I) {
842  if (Ex->getKind() == UETT_SizeOf) {
843  if (!T->isIncompleteType() && !T->isConstantSizeType()) {
844  assert(T->isVariableArrayType() && "Unknown non-constant-sized type.");
845 
846  // FIXME: Add support for VLA type arguments and VLA expressions.
847  // When that happens, we should probably refactor VLASizeChecker's code.
848  continue;
849  } else if (T->getAs<ObjCObjectType>()) {
850  // Some code tries to take the sizeof an ObjCObjectType, relying that
851  // the compiler has laid out its representation. Just report Unknown
852  // for these.
853  continue;
854  }
855  }
856 
857  APSInt Value = Ex->EvaluateKnownConstInt(getContext());
858  CharUnits amt = CharUnits::fromQuantity(Value.getZExtValue());
859 
860  ProgramStateRef state = (*I)->getState();
861  state = state->BindExpr(Ex, (*I)->getLocationContext(),
862  svalBuilder.makeIntVal(amt.getQuantity(),
863  Ex->getType()));
864  Bldr.generateNode(Ex, *I, state);
865  }
866 
867  getCheckerManager().runCheckersForPostStmt(Dst, EvalSet, Ex, *this);
868 }
869 
871  const UnaryOperator *U,
872  StmtNodeBuilder &Bldr) {
873  // FIXME: We can probably just have some magic in Environment::getSVal()
874  // that propagates values, instead of creating a new node here.
875  //
876  // Unary "+" is a no-op, similar to a parentheses. We still have places
877  // where it may be a block-level expression, so we need to
878  // generate an extra node that just propagates the value of the
879  // subexpression.
880  const Expr *Ex = U->getSubExpr()->IgnoreParens();
881  ProgramStateRef state = (*I)->getState();
882  const LocationContext *LCtx = (*I)->getLocationContext();
883  Bldr.generateNode(U, *I, state->BindExpr(U, LCtx,
884  state->getSVal(Ex, LCtx)));
885 }
886 
888  ExplodedNodeSet &Dst) {
889  // FIXME: Prechecks eventually go in ::Visit().
890  ExplodedNodeSet CheckedSet;
891  getCheckerManager().runCheckersForPreStmt(CheckedSet, Pred, U, *this);
892 
893  ExplodedNodeSet EvalSet;
894  StmtNodeBuilder Bldr(CheckedSet, EvalSet, *currBldrCtx);
895 
896  for (ExplodedNodeSet::iterator I = CheckedSet.begin(), E = CheckedSet.end();
897  I != E; ++I) {
898  switch (U->getOpcode()) {
899  default: {
900  Bldr.takeNodes(*I);
901  ExplodedNodeSet Tmp;
903  Bldr.addNodes(Tmp);
904  break;
905  }
906  case UO_Real: {
907  const Expr *Ex = U->getSubExpr()->IgnoreParens();
908 
909  // FIXME: We don't have complex SValues yet.
910  if (Ex->getType()->isAnyComplexType()) {
911  // Just report "Unknown."
912  break;
913  }
914 
915  // For all other types, UO_Real is an identity operation.
916  assert (U->getType() == Ex->getType());
917  ProgramStateRef state = (*I)->getState();
918  const LocationContext *LCtx = (*I)->getLocationContext();
919  Bldr.generateNode(U, *I, state->BindExpr(U, LCtx,
920  state->getSVal(Ex, LCtx)));
921  break;
922  }
923 
924  case UO_Imag: {
925  const Expr *Ex = U->getSubExpr()->IgnoreParens();
926  // FIXME: We don't have complex SValues yet.
927  if (Ex->getType()->isAnyComplexType()) {
928  // Just report "Unknown."
929  break;
930  }
931  // For all other types, UO_Imag returns 0.
932  ProgramStateRef state = (*I)->getState();
933  const LocationContext *LCtx = (*I)->getLocationContext();
934  SVal X = svalBuilder.makeZeroVal(Ex->getType());
935  Bldr.generateNode(U, *I, state->BindExpr(U, LCtx, X));
936  break;
937  }
938 
939  case UO_AddrOf: {
940  // Process pointer-to-member address operation.
941  const Expr *Ex = U->getSubExpr()->IgnoreParens();
942  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex)) {
943  const ValueDecl *VD = DRE->getDecl();
944 
945  if (isa<CXXMethodDecl>(VD) || isa<FieldDecl>(VD)) {
946  ProgramStateRef State = (*I)->getState();
947  const LocationContext *LCtx = (*I)->getLocationContext();
948  SVal SV = svalBuilder.getMemberPointer(cast<DeclaratorDecl>(VD));
949  Bldr.generateNode(U, *I, State->BindExpr(U, LCtx, SV));
950  break;
951  }
952  }
953  // Explicitly proceed with default handler for this case cascade.
954  handleUOExtension(I, U, Bldr);
955  break;
956  }
957  case UO_Plus:
958  assert(!U->isGLValue());
959  // FALL-THROUGH.
960  case UO_Deref:
961  case UO_Extension: {
962  handleUOExtension(I, U, Bldr);
963  break;
964  }
965 
966  case UO_LNot:
967  case UO_Minus:
968  case UO_Not: {
969  assert (!U->isGLValue());
970  const Expr *Ex = U->getSubExpr()->IgnoreParens();
971  ProgramStateRef state = (*I)->getState();
972  const LocationContext *LCtx = (*I)->getLocationContext();
973 
974  // Get the value of the subexpression.
975  SVal V = state->getSVal(Ex, LCtx);
976 
977  if (V.isUnknownOrUndef()) {
978  Bldr.generateNode(U, *I, state->BindExpr(U, LCtx, V));
979  break;
980  }
981 
982  switch (U->getOpcode()) {
983  default:
984  llvm_unreachable("Invalid Opcode.");
985  case UO_Not:
986  // FIXME: Do we need to handle promotions?
987  state = state->BindExpr(U, LCtx, evalComplement(V.castAs<NonLoc>()));
988  break;
989  case UO_Minus:
990  // FIXME: Do we need to handle promotions?
991  state = state->BindExpr(U, LCtx, evalMinus(V.castAs<NonLoc>()));
992  break;
993  case UO_LNot:
994  // C99 6.5.3.3: "The expression !E is equivalent to (0==E)."
995  //
996  // Note: technically we do "E == 0", but this is the same in the
997  // transfer functions as "0 == E".
998  SVal Result;
999  if (Optional<Loc> LV = V.getAs<Loc>()) {
1000  Loc X = svalBuilder.makeNullWithType(Ex->getType());
1001  Result = evalBinOp(state, BO_EQ, *LV, X, U->getType());
1002  } else if (Ex->getType()->isFloatingType()) {
1003  // FIXME: handle floating point types.
1004  Result = UnknownVal();
1005  } else {
1006  nonloc::ConcreteInt X(getBasicVals().getValue(0, Ex->getType()));
1007  Result = evalBinOp(state, BO_EQ, V.castAs<NonLoc>(), X,
1008  U->getType());
1009  }
1010 
1011  state = state->BindExpr(U, LCtx, Result);
1012  break;
1013  }
1014  Bldr.generateNode(U, *I, state);
1015  break;
1016  }
1017  }
1018  }
1019 
1020  getCheckerManager().runCheckersForPostStmt(Dst, EvalSet, U, *this);
1021 }
1022 
1024  ExplodedNode *Pred,
1025  ExplodedNodeSet &Dst) {
1026  // Handle ++ and -- (both pre- and post-increment).
1027  assert (U->isIncrementDecrementOp());
1028  const Expr *Ex = U->getSubExpr()->IgnoreParens();
1029 
1030  const LocationContext *LCtx = Pred->getLocationContext();
1031  ProgramStateRef state = Pred->getState();
1032  SVal loc = state->getSVal(Ex, LCtx);
1033 
1034  // Perform a load.
1035  ExplodedNodeSet Tmp;
1036  evalLoad(Tmp, U, Ex, Pred, state, loc);
1037 
1038  ExplodedNodeSet Dst2;
1039  StmtNodeBuilder Bldr(Tmp, Dst2, *currBldrCtx);
1040  for (ExplodedNodeSet::iterator I=Tmp.begin(), E=Tmp.end();I!=E;++I) {
1041 
1042  state = (*I)->getState();
1043  assert(LCtx == (*I)->getLocationContext());
1044  SVal V2_untested = state->getSVal(Ex, LCtx);
1045 
1046  // Propagate unknown and undefined values.
1047  if (V2_untested.isUnknownOrUndef()) {
1048  state = state->BindExpr(U, LCtx, V2_untested);
1049 
1050  // Perform the store, so that the uninitialized value detection happens.
1051  Bldr.takeNodes(*I);
1052  ExplodedNodeSet Dst3;
1053  evalStore(Dst3, U, U, *I, state, loc, V2_untested);
1054  Bldr.addNodes(Dst3);
1055 
1056  continue;
1057  }
1058  DefinedSVal V2 = V2_untested.castAs<DefinedSVal>();
1059 
1060  // Handle all other values.
1061  BinaryOperator::Opcode Op = U->isIncrementOp() ? BO_Add : BO_Sub;
1062 
1063  // If the UnaryOperator has non-location type, use its type to create the
1064  // constant value. If the UnaryOperator has location type, create the
1065  // constant with int type and pointer width.
1066  SVal RHS;
1067  SVal Result;
1068 
1069  if (U->getType()->isAnyPointerType())
1070  RHS = svalBuilder.makeArrayIndex(1);
1071  else if (U->getType()->isIntegralOrEnumerationType())
1072  RHS = svalBuilder.makeIntVal(1, U->getType());
1073  else
1074  RHS = UnknownVal();
1075 
1076  // The use of an operand of type bool with the ++ operators is deprecated
1077  // but valid until C++17. And if the operand of the ++ operator is of type
1078  // bool, it is set to true until C++17. Note that for '_Bool', it is also
1079  // set to true when it encounters ++ operator.
1080  if (U->getType()->isBooleanType() && U->isIncrementOp())
1081  Result = svalBuilder.makeTruthVal(true, U->getType());
1082  else
1083  Result = evalBinOp(state, Op, V2, RHS, U->getType());
1084 
1085  // Conjure a new symbol if necessary to recover precision.
1086  if (Result.isUnknown()){
1087  DefinedOrUnknownSVal SymVal =
1088  svalBuilder.conjureSymbolVal(nullptr, U, LCtx,
1089  currBldrCtx->blockCount());
1090  Result = SymVal;
1091 
1092  // If the value is a location, ++/-- should always preserve
1093  // non-nullness. Check if the original value was non-null, and if so
1094  // propagate that constraint.
1095  if (Loc::isLocType(U->getType())) {
1096  DefinedOrUnknownSVal Constraint =
1097  svalBuilder.evalEQ(state, V2,svalBuilder.makeZeroVal(U->getType()));
1098 
1099  if (!state->assume(Constraint, true)) {
1100  // It isn't feasible for the original value to be null.
1101  // Propagate this constraint.
1102  Constraint = svalBuilder.evalEQ(state, SymVal,
1103  svalBuilder.makeZeroVal(U->getType()));
1104 
1105  state = state->assume(Constraint, false);
1106  assert(state);
1107  }
1108  }
1109  }
1110 
1111  // Since the lvalue-to-rvalue conversion is explicit in the AST,
1112  // we bind an l-value if the operator is prefix and an lvalue (in C++).
1113  if (U->isGLValue())
1114  state = state->BindExpr(U, LCtx, loc);
1115  else
1116  state = state->BindExpr(U, LCtx, U->isPostfix() ? V2 : Result);
1117 
1118  // Perform the store.
1119  Bldr.takeNodes(*I);
1120  ExplodedNodeSet Dst3;
1121  evalStore(Dst3, U, U, *I, state, loc, Result);
1122  Bldr.addNodes(Dst3);
1123  }
1124  Dst.insert(Dst2);
1125 }
SVal attemptDownCast(SVal Base, QualType DerivedPtrType, bool &Failed)
Attempts to do a down cast.
Definition: Store.cpp:305
const BlockDecl * getBlockDecl() const
Definition: Expr.h:4949
nonloc::ConcreteInt makeIntVal(const IntegerLiteral *integer)
Definition: SValBuilder.h:279
DefinedSVal getBlockPointer(const BlockDecl *block, CanQualType locTy, const LocationContext *locContext, unsigned blockCount)
reverse_iterator rbegin()
Definition: Expr.h:4161
SVal evalDerivedToBase(SVal Derived, const CastExpr *Cast)
Evaluates a chain of derived-to-base casts through the path specified in Cast.
Definition: Store.cpp:248
bool empty() const
Definition: CFG.h:713
A (possibly-)qualified type.
Definition: Type.h:655
bool isArrayType() const
Definition: Type.h:6155
succ_iterator succ_begin()
Definition: CFG.h:750
capture_const_iterator capture_begin() const
Definition: Decl.h:3974
const Expr * getInit(unsigned Init) const
Definition: Expr.h:4004
unsigned blockCount() const
Returns the number of times the current basic block has been visited on the exploded graph path...
Definition: CoreEngine.h:212
This builder class is useful for generating nodes that resulted from visiting a statement.
Definition: CoreEngine.h:370
bool isRecordType() const
Definition: Type.h:6179
const CFGBlock * getSrc() const
Definition: ProgramPoint.h:485
QualType getLValueReferenceType(QualType T, bool SpelledAsLValue=true) const
Return the uniqued reference to the type for an lvalue reference to the specified type...
Opcode getOpcode() const
Definition: Expr.h:3110
StringRef P
SVal evalBinOp(ProgramStateRef state, BinaryOperator::Opcode op, NonLoc L, NonLoc R, QualType T)
Definition: ExprEngine.h:568
Represents a point after we ran remove dead bindings BEFORE processing the given statement.
Definition: ProgramPoint.h:447
T castAs() const
Convert to the specified CFGElement type, asserting that this CFGElement is of the desired type...
Definition: CFG.h:98
const ProgramStateRef & getState() const
SVal evalCast(SVal val, QualType castTy, QualType originalType)
Value representing integer constant.
Definition: SVals.h:377
capture_const_iterator capture_end() const
Definition: Decl.h:3975
unsigned succ_size() const
Definition: CFG.h:768
void VisitUnaryOperator(const UnaryOperator *B, ExplodedNode *Pred, ExplodedNodeSet &Dst)
VisitUnaryOperator - Transfer function logic for unary operators.
void takeNodes(const ExplodedNodeSet &S)
Definition: CoreEngine.h:321
bool EvaluateAsInt(llvm::APSInt &Result, const ASTContext &Ctx, SideEffectsKind AllowSideEffects=SE_NoSideEffects) const
EvaluateAsInt - Return true if this is a constant which we can fold and convert to an integer...
void handleUOExtension(ExplodedNodeSet::iterator I, const UnaryOperator *U, StmtNodeBuilder &Bldr)
Represents a variable declaration or definition.
Definition: Decl.h:812
CompoundLiteralExpr - [C99 6.5.2.5].
Definition: Expr.h:2715
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:6519
NonLoc makeArrayIndex(uint64_t idx)
Definition: SValBuilder.h:273
void evalStore(ExplodedNodeSet &Dst, const Expr *AssignE, const Expr *StoreE, ExplodedNode *Pred, ProgramStateRef St, SVal TargetLV, SVal Val, const ProgramPointTag *tag=nullptr)
evalStore - Handle the semantics of a store via an assignment.
static bool isAssignmentOp(Opcode Opc)
Definition: Expr.h:3192
Defines the clang::Expr interface and subclasses for C++ expressions.
bool isVariableArrayType() const
Definition: Type.h:6167
InitExprsTy::const_reverse_iterator const_reverse_iterator
Definition: Expr.h:4155
Represents a class type in Objective C.
Definition: Type.h:5348
Value representing pointer-to-member.
Definition: SVals.h:522
LineState State
SVal evalIntegralCast(ProgramStateRef state, SVal val, QualType castTy, QualType originalType)
Loc makeNullWithType(QualType type)
Create NULL pointer, with proper pointer bit-width for given address space.
Definition: SValBuilder.h:346
static bool isIncrementDecrementOp(Opcode Op)
Definition: Expr.h:1852
bool isReferenceType() const
Definition: Type.h:6118
i32 captured_struct **param SharedsTy A type which contains references the shared variables *param Shareds Context with the list of shared variables from the p *TaskFunction *param Data Additional data for task generation like final * state
bool isIntegralOrEnumerationType() const
Determine whether this type is an integral or enumeration type.
Definition: Type.h:6433
llvm::ImmutableList< SVal > prependSVal(SVal X, llvm::ImmutableList< SVal > L)
static bool isLocType(QualType T)
Definition: SVals.h:327
bool isGLValue() const
Definition: Expr.h:252
Describes an C or C++ initializer list.
Definition: Expr.h:3956
void VisitOffsetOfExpr(const OffsetOfExpr *Ex, ExplodedNode *Pred, ExplodedNodeSet &Dst)
VisitOffsetOfExpr - Transfer function for offsetof.
BinaryOperatorKind
BlockDataRegion - A region that represents a block instance.
Definition: MemRegion.h:668
ExplodedNode * generateSink(const Stmt *S, ExplodedNode *Pred, ProgramStateRef St, const ProgramPointTag *tag=nullptr, ProgramPoint::Kind K=ProgramPoint::PostStmtKind)
Definition: CoreEngine.h:409
CharUnits - This is an opaque type for sizes expressed in character units.
Definition: CharUnits.h:38
path_iterator path_begin()
Definition: Expr.h:2861
const LocationContext * getLocationContext() const
A builtin binary operation expression such as "x + y" or "x <= y".
Definition: Expr.h:3069
bool isUnknown() const
Definition: SVals.h:137
NonLoc makePointerToMember(const DeclaratorDecl *DD)
Definition: SValBuilder.h:261
static bool isPostfix(Opcode Op)
isPostfix - Return true if this is a postfix operation, like x++.
Definition: Expr.h:1826
bool isRValueReferenceType() const
Definition: Type.h:6126
NonLoc makeCompoundVal(QualType type, llvm::ImmutableList< SVal > vals)
Definition: SValBuilder.h:251
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:2788
SVal evalComplement(SVal X)
Definition: ExprEngine.h:547
void VisitDeclStmt(const DeclStmt *DS, ExplodedNode *Pred, ExplodedNodeSet &Dst)
VisitDeclStmt - Transfer function logic for DeclStmts.
unsigned pred_size() const
bool isConstant() const
Definition: SVals.cpp:218
void evalBind(ExplodedNodeSet &Dst, const Stmt *StoreE, ExplodedNode *Pred, SVal location, SVal Val, bool atDeclInit=false, const ProgramPoint *PP=nullptr)
evalBind - Handle the semantics of binding a value to a specific location.
CheckerManager & getCheckerManager() const
Definition: ExprEngine.h:186
void VisitLogicalExpr(const BinaryOperator *B, ExplodedNode *Pred, ExplodedNodeSet &Dst)
VisitLogicalExpr - Transfer function logic for &#39;&&&#39;, &#39;||&#39;.
UnaryExprOrTypeTraitExpr - expression with either a type or (unevaluated) expression operand...
Definition: Expr.h:2105
CFGBlock - Represents a single basic block in a source-level CFG.
Definition: CFG.h:548
void VisitInitListExpr(const InitListExpr *E, ExplodedNode *Pred, ExplodedNodeSet &Dst)
QuantityType getQuantity() const
getQuantity - Get the raw integer representation of this quantity.
Definition: CharUnits.h:179
llvm::APSInt EvaluateKnownConstInt(const ASTContext &Ctx, SmallVectorImpl< PartialDiagnosticAt > *Diag=nullptr) const
EvaluateKnownConstInt - Call EvaluateAsRValue and return the folded integer.
void runCheckersForPostStmt(ExplodedNodeSet &Dst, const ExplodedNodeSet &Src, const Stmt *S, ExprEngine &Eng, bool wasInlined=false)
Run checkers for post-visiting Stmts.
DefinedOrUnknownSVal makeZeroVal(QualType type)
Construct an SVal representing &#39;0&#39; for the specified type.
Definition: SValBuilder.cpp:53
Pepresents a block literal declaration, which is like an unnamed FunctionDecl.
Definition: Decl.h:3842
Represent the declaration of a variable (in which case it is an lvalue) a function (in which case it ...
Definition: Decl.h:636
Expr - This represents one expression.
Definition: Expr.h:106
static SVal conjureOffsetSymbolOnLocation(SVal Symbol, SVal Other, Expr *Expression, SValBuilder &svalBuilder, unsigned Count, const LocationContext *LCtx)
Optionally conjure and return a symbol for offset when processing an expression Expression.
Definition: ExprEngineC.cpp:29
void VisitCast(const CastExpr *CastE, const Expr *Ex, ExplodedNode *Pred, ExplodedNodeSet &Dst)
VisitCast - Transfer function logic for all casts (implicit and explicit).
BlockExpr - Adaptor class for mixing a BlockDecl with expressions.
Definition: Expr.h:4935
unsigned getNumInits() const
Definition: Expr.h:3986
const ExplodedNodeSet & getResults()
Definition: CoreEngine.h:298
bool isAnyComplexType() const
Definition: Type.h:6187
static CharUnits fromQuantity(QuantityType Quantity)
fromQuantity - Construct a CharUnits quantity from a raw integer type.
Definition: CharUnits.h:63
static SVal getValue(SVal val, SValBuilder &svalBuilder)
bool isSignedIntegerType() const
Return true if this is an integer type that is signed, according to C99 6.2.5p4 [char, signed char, short, int, long..], or an enum decl which has a signed representation.
Definition: Type.cpp:1838
const CFGBlock * getDst() const
Definition: ProgramPoint.h:489
QualType getType() const
Definition: Expr.h:128
QualType getTypeOfArgument() const
Gets the argument type, or the type of the argument expression, whichever is appropriate.
Definition: Expr.h:2168
The reason for pointer escape is unknown.
ASTContext & getContext() const
getContext - Return the ASTContext associated with this analysis.
Definition: ExprEngine.h:182
UnaryOperator - This represents the unary-expression&#39;s (except sizeof and alignof), the postinc/postdec operators from postfix-expression, and various extensions.
Definition: Expr.h:1782
void evalLoad(ExplodedNodeSet &Dst, const Expr *NodeEx, const Expr *BoundExpr, ExplodedNode *Pred, ProgramStateRef St, SVal location, const ProgramPointTag *tag=nullptr, QualType LoadTy=QualType())
Simulate a read of the result of Ex.
reverse_iterator rbegin()
Definition: CFG.h:707
const VarDecl * getDecl() const
Definition: MemRegion.h:943
Optional< T > getAs() const
Convert to the specified SVal type, returning None if this SVal is not of the desired type...
Definition: SVals.h:112
CFGTerminator getTerminator()
Definition: CFG.h:839
OpaqueValueExpr - An expression referring to an opaque object of a fixed type and value class...
Definition: Expr.h:875
bool isBuiltinType() const
Helper methods to distinguish type categories.
Definition: Type.h:6175
void VisitGuardedExpr(const Expr *Ex, const Expr *L, const Expr *R, ExplodedNode *Pred, ExplodedNodeSet &Dst)
VisitGuardedExpr - Transfer function logic for ?, __builtin_choose.
DefinedOrUnknownSVal conjureSymbolVal(const void *symbolTag, const Expr *expr, const LocationContext *LCtx, unsigned count)
Create a new symbol with a unique &#39;name&#39;.
Expr * getSubExpr() const
Definition: Expr.h:1809
T castAs() const
Convert to the specified ProgramPoint type, asserting that this ProgramPoint is of the desired type...
Definition: ProgramPoint.h:141
CastKind getCastKind() const
Definition: Expr.h:2835
const MemRegion * getAsRegion() const
Definition: SVals.cpp:151
DeclStmt - Adaptor class for mixing declarations with statements and expressions. ...
Definition: Stmt.h:499
void VisitCompoundLiteralExpr(const CompoundLiteralExpr *CL, ExplodedNode *Pred, ExplodedNodeSet &Dst)
VisitCompoundLiteralExpr - Transfer function logic for compound literals.
ProgramStateRef handleLVectorSplat(ProgramStateRef state, const LocationContext *LCtx, const CastExpr *CastE, StmtNodeBuilder &Bldr, ExplodedNode *Pred)
ProgramPoint getLocation() const
getLocation - Returns the edge associated with the given node.
SVal - This represents a symbolic expression, which can be either an L-value or an R-value...
Definition: SVals.h:76
UnaryExprOrTypeTrait getKind() const
Definition: Expr.h:2136
decl_iterator decl_begin()
Definition: Stmt.h:552
void VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *Ex, ExplodedNode *Pred, ExplodedNodeSet &Dst)
VisitUnaryExprOrTypeTraitExpr - Transfer function for sizeof.
bool isAnyPointerType() const
Definition: Type.h:6110
BasicValueFactory & getBasicVals()
Definition: ExprEngine.h:379
void runCheckersForPreStmt(ExplodedNodeSet &Dst, const ExplodedNodeSet &Src, const Stmt *S, ExprEngine &Eng)
Run checkers for pre-visiting Stmts.
bool isVectorType() const
Definition: Type.h:6191
void insert(const ExplodedNodeSet &S)
const Expr * getInitializer() const
Definition: Expr.h:2741
Expr * getLHS() const
Definition: Expr.h:3113
Dataflow Directional Tag Classes.
void VisitIncrementDecrementOperator(const UnaryOperator *U, ExplodedNode *Pred, ExplodedNodeSet &Dst)
Handle ++ and – (both pre- and post-increment).
SValBuilder & getSValBuilder()
Definition: ExprEngine.h:190
void addNodes(const ExplodedNodeSet &S)
Definition: CoreEngine.h:327
StoreManager & getStoreManager()
Definition: ExprEngine.h:372
bool isZeroConstant() const
Definition: SVals.cpp:230
const Expr * getInit() const
Definition: Decl.h:1217
bool isBooleanType() const
Definition: Type.h:6446
SVal evalEQ(ProgramStateRef state, SVal lhs, SVal rhs)
ExplicitCastExpr - An explicit cast written in the source code.
Definition: Expr.h:2972
bool isSingleDecl() const
isSingleDecl - This method returns true if this DeclStmt refers to a single Decl. ...
Definition: Stmt.h:512
Stmt * getStmt()
Definition: CFG.h:506
path_iterator path_end()
Definition: Expr.h:2862
ProgramStateRef handleLValueBitCast(ProgramStateRef state, const Expr *Ex, const LocationContext *LCtx, QualType T, QualType ExTy, const CastExpr *CastE, StmtNodeBuilder &Bldr, ExplodedNode *Pred)
T castAs() const
Convert to the specified SVal type, asserting that this SVal is of the desired type.
Definition: SVals.h:104
bool isConstantSizeType() const
Return true if this is not a variable sized type, according to the rules of C99 6.7.5p3.
Definition: Type.cpp:2014
SVal evalMinus(SVal X)
Definition: ExprEngine.h:543
DefinedSVal getMemberPointer(const DeclaratorDecl *DD)
Opcode getOpcode() const
Definition: Expr.h:1806
static bool isAdditiveOp(Opcode Opc)
Definition: Expr.h:3145
uint64_t getTypeSize(QualType T) const
Return the size of the specified (complete) type T, in bits.
Definition: ASTContext.h:2046
bool isIncompleteType(NamedDecl **Def=nullptr) const
Types are partitioned into 3 broad categories (C99 6.2.5p1): object types, function types...
Definition: Type.cpp:2024
static bool isIncrementOp(Opcode Op)
Definition: Expr.h:1838
CanQualType getCanonicalType(QualType T) const
Return the canonical (structural) type corresponding to the specified potentially non-canonical type ...
Definition: ASTContext.h:2213
bool isLValueReferenceType() const
Definition: Type.h:6122
reverse_iterator rend()
Definition: Expr.h:4163
X
Add a minimal nested name specifier fixit hint to allow lookup of a tag name from an outer enclosing ...
Definition: SemaDecl.cpp:13530
void VisitBlockExpr(const BlockExpr *BE, ExplodedNode *Pred, ExplodedNodeSet &Dst)
VisitBlockExpr - Transfer function logic for BlockExprs.
Defines the C++ Decl subclasses, other than those for templates (found in DeclTemplate.h) and friends (in DeclFriend.h).
static bool isCompoundAssignmentOp(Opcode Opc)
Definition: Expr.h:3197
QualType getRValueReferenceType(QualType T) const
Return the uniqued reference to the type for an rvalue reference to the specified type...
pred_iterator pred_begin()
CFGElement - Represents a top-level expression in a basic block.
Definition: CFG.h:55
QualType getPointerType(QualType T) const
Return the uniqued reference to the type for a pointer to the specified type.
This class is used for builtin types like &#39;int&#39;.
Definition: Type.h:2244
CFGTerminator - Represents CFGBlock terminator statement.
Definition: CFG.h:498
ExplodedNode * generateNode(const Stmt *S, ExplodedNode *Pred, ProgramStateRef St, const ProgramPointTag *tag=nullptr, ProgramPoint::Kind K=ProgramPoint::PostStmtKind)
Definition: CoreEngine.h:399
bool isUndef() const
Definition: SVals.h:141
A reference to a declared variable, function, enum, etc.
Definition: Expr.h:972
Expr * getRHS() const
Definition: Expr.h:3115
nonloc::ConcreteInt makeTruthVal(bool b, QualType type)
Definition: SValBuilder.h:335
ProgramStateRef escapeValue(ProgramStateRef State, SVal V, PointerEscapeKind K) const
A simple wrapper when you only need to notify checkers of pointer-escape of a single value...
Optional< T > getAs() const
Convert to the specified ProgramPoint type, returning None if this ProgramPoint is not of the desired...
Definition: ProgramPoint.h:152
OffsetOfExpr - [C99 7.17] - This represents an expression of the form offsetof(record-type, member-designator).
Definition: Expr.h:2000
void VisitBinaryOperator(const BinaryOperator *B, ExplodedNode *Pred, ExplodedNodeSet &Dst)
VisitBinaryOperator - Transfer function logic for binary operators.
Definition: ExprEngineC.cpp:41
bool isUnknownOrUndef() const
Definition: SVals.h:145
llvm::ImmutableList< SVal > getEmptySValList()
Expr * IgnoreParens() LLVM_READONLY
IgnoreParens - Ignore parentheses.
Definition: Expr.cpp:2486