1 //== SVals.h - Abstract Values for Static Analysis ---------*- C++ -*--==//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines SVal, Loc, and NonLoc, classes that represent
11 // abstract r-values for use with path-sensitive value tracking.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CLANG_GR_RVALUE_H
16 #define LLVM_CLANG_GR_RVALUE_H
18 #include "clang/Basic/LLVM.h"
19 #include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h"
20 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState_Fwd.h"
21 #include "llvm/ADT/ImmutableList.h"
23 //==------------------------------------------------------------------------==//
25 //==------------------------------------------------------------------------==//
31 class CompoundValData;
32 class LazyCompoundValData;
34 class BasicValueFactory;
37 class MemRegionManager;
38 class ProgramStateManager;
41 /// SVal - This represents a symbolic expression, which can be either
42 /// an L-value or an R-value.
47 // The enumerators must be representable using 2 bits.
48 UndefinedKind = 0, // for subclass UndefinedVal (an uninitialized value)
49 UnknownKind = 1, // for subclass UnknownVal (a void value)
50 LocKind = 2, // for subclass Loc (an L-value)
51 NonLocKind = 3 // for subclass NonLoc (an R-value that's not
54 enum { BaseBits = 2, BaseMask = 0x3 };
59 /// The lowest 2 bits are a BaseKind (0 -- 3).
60 /// The higher bits are an unsigned "kind" value.
63 explicit SVal(const void *d, bool isLoc, unsigned ValKind)
64 : Data(d), Kind((isLoc ? LocKind : NonLocKind) | (ValKind << BaseBits)) {}
66 explicit SVal(BaseKind k, const void *D = NULL)
70 explicit SVal() : Data(0), Kind(0) {}
72 /// BufferTy - A temporary buffer to hold a set of SVals.
73 typedef SmallVector<SVal,5> BufferTy;
75 inline unsigned getRawKind() const { return Kind; }
76 inline BaseKind getBaseKind() const { return (BaseKind) (Kind & BaseMask); }
77 inline unsigned getSubKind() const { return (Kind & ~BaseMask) >> BaseBits; }
79 // This method is required for using SVal in a FoldingSetNode. It
80 // extracts a unique signature for this SVal object.
81 inline void Profile(llvm::FoldingSetNodeID& ID) const {
82 ID.AddInteger((unsigned) getRawKind());
86 inline bool operator==(const SVal& R) const {
87 return getRawKind() == R.getRawKind() && Data == R.Data;
90 inline bool operator!=(const SVal& R) const {
94 inline bool isUnknown() const {
95 return getRawKind() == UnknownKind;
98 inline bool isUndef() const {
99 return getRawKind() == UndefinedKind;
102 inline bool isUnknownOrUndef() const {
103 return getRawKind() <= UnknownKind;
106 inline bool isValid() const {
107 return getRawKind() > UnknownKind;
110 bool isConstant() const;
112 bool isConstant(int I) const;
114 bool isZeroConstant() const;
116 /// hasConjuredSymbol - If this SVal wraps a conjured symbol, return true;
117 bool hasConjuredSymbol() const;
119 /// getAsFunctionDecl - If this SVal is a MemRegionVal and wraps a
120 /// CodeTextRegion wrapping a FunctionDecl, return that FunctionDecl.
121 /// Otherwise return 0.
122 const FunctionDecl *getAsFunctionDecl() const;
124 /// If this SVal is a location (subclasses Loc) and
125 /// wraps a symbol, return that SymbolRef. Otherwise return 0.
126 SymbolRef getAsLocSymbol() const;
128 /// Get the symbol in the SVal or its base region.
129 SymbolRef getLocSymbolInBase() const;
131 /// If this SVal wraps a symbol return that SymbolRef.
132 /// Otherwise, return 0.
133 SymbolRef getAsSymbol() const;
135 /// getAsSymbolicExpression - If this Sval wraps a symbolic expression then
136 /// return that expression. Otherwise return NULL.
137 const SymExpr *getAsSymbolicExpression() const;
139 const SymExpr* getAsSymExpr() const;
141 const MemRegion *getAsRegion() const;
143 void dumpToStream(raw_ostream &OS) const;
146 SymExpr::symbol_iterator symbol_begin() const {
147 const SymExpr *SE = getAsSymbolicExpression();
149 return SE->symbol_begin();
151 return SymExpr::symbol_iterator();
154 SymExpr::symbol_iterator symbol_end() const {
155 return SymExpr::symbol_end();
158 // Implement isa<T> support.
159 static inline bool classof(const SVal*) { return true; }
163 class UndefinedVal : public SVal {
165 UndefinedVal() : SVal(UndefinedKind) {}
167 static inline bool classof(const SVal* V) {
168 return V->getBaseKind() == UndefinedKind;
172 class DefinedOrUnknownSVal : public SVal {
174 // Do not implement. We want calling these methods to be a compiler
175 // error since they are tautologically false.
176 bool isUndef() const;
177 bool isValid() const;
180 explicit DefinedOrUnknownSVal(const void *d, bool isLoc, unsigned ValKind)
181 : SVal(d, isLoc, ValKind) {}
183 explicit DefinedOrUnknownSVal(BaseKind k, void *D = NULL)
187 // Implement isa<T> support.
188 static inline bool classof(const SVal *V) {
189 return !V->isUndef();
193 class UnknownVal : public DefinedOrUnknownSVal {
195 explicit UnknownVal() : DefinedOrUnknownSVal(UnknownKind) {}
197 static inline bool classof(const SVal *V) {
198 return V->getBaseKind() == UnknownKind;
202 class DefinedSVal : public DefinedOrUnknownSVal {
204 // Do not implement. We want calling these methods to be a compiler
205 // error since they are tautologically true/false.
206 bool isUnknown() const;
207 bool isUnknownOrUndef() const;
208 bool isValid() const;
210 explicit DefinedSVal(const void *d, bool isLoc, unsigned ValKind)
211 : DefinedOrUnknownSVal(d, isLoc, ValKind) {}
213 // Implement isa<T> support.
214 static inline bool classof(const SVal *V) {
215 return !V->isUnknownOrUndef();
219 class NonLoc : public DefinedSVal {
221 explicit NonLoc(unsigned SubKind, const void *d)
222 : DefinedSVal(d, false, SubKind) {}
225 void dumpToStream(raw_ostream &Out) const;
227 // Implement isa<T> support.
228 static inline bool classof(const SVal* V) {
229 return V->getBaseKind() == NonLocKind;
233 class Loc : public DefinedSVal {
235 explicit Loc(unsigned SubKind, const void *D)
236 : DefinedSVal(const_cast<void*>(D), true, SubKind) {}
239 void dumpToStream(raw_ostream &Out) const;
241 Loc(const Loc& X) : DefinedSVal(X.Data, true, X.getSubKind()) {}
243 // Implement isa<T> support.
244 static inline bool classof(const SVal* V) {
245 return V->getBaseKind() == LocKind;
248 static inline bool isLocType(QualType T) {
249 return T->isAnyPointerType() || T->isBlockPointerType() ||
250 T->isReferenceType();
254 //==------------------------------------------------------------------------==//
255 // Subclasses of NonLoc.
256 //==------------------------------------------------------------------------==//
260 enum Kind { ConcreteIntKind, SymbolValKind,
261 LocAsIntegerKind, CompoundValKind, LazyCompoundValKind };
263 /// \brief Represents symbolic expression.
264 class SymbolVal : public NonLoc {
266 SymbolVal(SymbolRef sym) : NonLoc(SymbolValKind, sym) {}
268 SymbolRef getSymbol() const {
269 return (const SymExpr*) Data;
272 bool isExpression() {
273 return !isa<SymbolData>(getSymbol());
276 static inline bool classof(const SVal* V) {
277 return V->getBaseKind() == NonLocKind &&
278 V->getSubKind() == SymbolValKind;
281 static inline bool classof(const NonLoc* V) {
282 return V->getSubKind() == SymbolValKind;
286 /// \brief Value representing integer constant.
287 class ConcreteInt : public NonLoc {
289 explicit ConcreteInt(const llvm::APSInt& V) : NonLoc(ConcreteIntKind, &V) {}
291 const llvm::APSInt& getValue() const {
292 return *static_cast<const llvm::APSInt*>(Data);
295 // Transfer functions for binary/unary operations on ConcreteInts.
296 SVal evalBinOp(SValBuilder &svalBuilder, BinaryOperator::Opcode Op,
297 const ConcreteInt& R) const;
299 ConcreteInt evalComplement(SValBuilder &svalBuilder) const;
301 ConcreteInt evalMinus(SValBuilder &svalBuilder) const;
303 // Implement isa<T> support.
304 static inline bool classof(const SVal* V) {
305 return V->getBaseKind() == NonLocKind &&
306 V->getSubKind() == ConcreteIntKind;
309 static inline bool classof(const NonLoc* V) {
310 return V->getSubKind() == ConcreteIntKind;
314 class LocAsInteger : public NonLoc {
315 friend class ento::SValBuilder;
317 explicit LocAsInteger(const std::pair<SVal, uintptr_t>& data) :
318 NonLoc(LocAsIntegerKind, &data) {
319 assert (isa<Loc>(data.first));
325 const std::pair<SVal, uintptr_t> *D =
326 static_cast<const std::pair<SVal, uintptr_t> *>(Data);
327 return cast<Loc>(D->first);
330 const Loc& getPersistentLoc() const {
331 const std::pair<SVal, uintptr_t> *D =
332 static_cast<const std::pair<SVal, uintptr_t> *>(Data);
333 const SVal& V = D->first;
337 unsigned getNumBits() const {
338 const std::pair<SVal, uintptr_t> *D =
339 static_cast<const std::pair<SVal, uintptr_t> *>(Data);
343 // Implement isa<T> support.
344 static inline bool classof(const SVal* V) {
345 return V->getBaseKind() == NonLocKind &&
346 V->getSubKind() == LocAsIntegerKind;
349 static inline bool classof(const NonLoc* V) {
350 return V->getSubKind() == LocAsIntegerKind;
354 class CompoundVal : public NonLoc {
355 friend class ento::SValBuilder;
357 explicit CompoundVal(const CompoundValData* D) : NonLoc(CompoundValKind, D) {}
360 const CompoundValData* getValue() const {
361 return static_cast<const CompoundValData*>(Data);
364 typedef llvm::ImmutableList<SVal>::iterator iterator;
365 iterator begin() const;
366 iterator end() const;
368 static bool classof(const SVal* V) {
369 return V->getBaseKind() == NonLocKind && V->getSubKind() == CompoundValKind;
372 static bool classof(const NonLoc* V) {
373 return V->getSubKind() == CompoundValKind;
377 class LazyCompoundVal : public NonLoc {
378 friend class ento::SValBuilder;
380 explicit LazyCompoundVal(const LazyCompoundValData *D)
381 : NonLoc(LazyCompoundValKind, D) {}
383 const LazyCompoundValData *getCVData() const {
384 return static_cast<const LazyCompoundValData*>(Data);
386 const void *getStore() const;
387 const TypedRegion *getRegion() const;
389 static bool classof(const SVal *V) {
390 return V->getBaseKind() == NonLocKind &&
391 V->getSubKind() == LazyCompoundValKind;
393 static bool classof(const NonLoc *V) {
394 return V->getSubKind() == LazyCompoundValKind;
398 } // end namespace ento::nonloc
400 //==------------------------------------------------------------------------==//
401 // Subclasses of Loc.
402 //==------------------------------------------------------------------------==//
406 enum Kind { GotoLabelKind, MemRegionKind, ConcreteIntKind };
408 class GotoLabel : public Loc {
410 explicit GotoLabel(LabelDecl *Label) : Loc(GotoLabelKind, Label) {}
412 const LabelDecl *getLabel() const {
413 return static_cast<const LabelDecl*>(Data);
416 static inline bool classof(const SVal* V) {
417 return V->getBaseKind() == LocKind && V->getSubKind() == GotoLabelKind;
420 static inline bool classof(const Loc* V) {
421 return V->getSubKind() == GotoLabelKind;
426 class MemRegionVal : public Loc {
428 explicit MemRegionVal(const MemRegion* r) : Loc(MemRegionKind, r) {}
430 /// \brief Get the underlining region.
431 const MemRegion* getRegion() const {
432 return static_cast<const MemRegion*>(Data);
435 /// \brief Get the underlining region and strip casts.
436 const MemRegion* stripCasts(bool StripBaseCasts = true) const;
438 template <typename REGION>
439 const REGION* getRegionAs() const {
440 return llvm::dyn_cast<REGION>(getRegion());
443 inline bool operator==(const MemRegionVal& R) const {
444 return getRegion() == R.getRegion();
447 inline bool operator!=(const MemRegionVal& R) const {
448 return getRegion() != R.getRegion();
451 // Implement isa<T> support.
452 static inline bool classof(const SVal* V) {
453 return V->getBaseKind() == LocKind &&
454 V->getSubKind() == MemRegionKind;
457 static inline bool classof(const Loc* V) {
458 return V->getSubKind() == MemRegionKind;
462 class ConcreteInt : public Loc {
464 explicit ConcreteInt(const llvm::APSInt& V) : Loc(ConcreteIntKind, &V) {}
466 const llvm::APSInt& getValue() const {
467 return *static_cast<const llvm::APSInt*>(Data);
470 // Transfer functions for binary/unary operations on ConcreteInts.
471 SVal evalBinOp(BasicValueFactory& BasicVals, BinaryOperator::Opcode Op,
472 const ConcreteInt& R) const;
474 // Implement isa<T> support.
475 static inline bool classof(const SVal* V) {
476 return V->getBaseKind() == LocKind &&
477 V->getSubKind() == ConcreteIntKind;
480 static inline bool classof(const Loc* V) {
481 return V->getSubKind() == ConcreteIntKind;
485 } // end ento::loc namespace
486 } // end GR namespace
488 } // end clang namespace
491 static inline raw_ostream &operator<<(raw_ostream &os,
492 clang::ento::SVal V) {
497 } // end llvm namespace