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();
160 class UndefinedVal : public SVal {
162 UndefinedVal() : SVal(UndefinedKind) {}
164 static inline bool classof(const SVal* V) {
165 return V->getBaseKind() == UndefinedKind;
169 class DefinedOrUnknownSVal : public SVal {
171 // Do not implement. We want calling these methods to be a compiler
172 // error since they are tautologically false.
173 bool isUndef() const;
174 bool isValid() const;
177 explicit DefinedOrUnknownSVal(const void *d, bool isLoc, unsigned ValKind)
178 : SVal(d, isLoc, ValKind) {}
180 explicit DefinedOrUnknownSVal(BaseKind k, void *D = NULL)
184 // Implement isa<T> support.
185 static inline bool classof(const SVal *V) {
186 return !V->isUndef();
190 class UnknownVal : public DefinedOrUnknownSVal {
192 explicit UnknownVal() : DefinedOrUnknownSVal(UnknownKind) {}
194 static inline bool classof(const SVal *V) {
195 return V->getBaseKind() == UnknownKind;
199 class DefinedSVal : public DefinedOrUnknownSVal {
201 // Do not implement. We want calling these methods to be a compiler
202 // error since they are tautologically true/false.
203 bool isUnknown() const;
204 bool isUnknownOrUndef() const;
205 bool isValid() const;
207 explicit DefinedSVal(const void *d, bool isLoc, unsigned ValKind)
208 : DefinedOrUnknownSVal(d, isLoc, ValKind) {}
210 // Implement isa<T> support.
211 static inline bool classof(const SVal *V) {
212 return !V->isUnknownOrUndef();
216 class NonLoc : public DefinedSVal {
218 explicit NonLoc(unsigned SubKind, const void *d)
219 : DefinedSVal(d, false, SubKind) {}
222 void dumpToStream(raw_ostream &Out) const;
224 // Implement isa<T> support.
225 static inline bool classof(const SVal* V) {
226 return V->getBaseKind() == NonLocKind;
230 class Loc : public DefinedSVal {
232 explicit Loc(unsigned SubKind, const void *D)
233 : DefinedSVal(const_cast<void*>(D), true, SubKind) {}
236 void dumpToStream(raw_ostream &Out) const;
238 Loc(const Loc& X) : DefinedSVal(X.Data, true, X.getSubKind()) {}
240 // Implement isa<T> support.
241 static inline bool classof(const SVal* V) {
242 return V->getBaseKind() == LocKind;
245 static inline bool isLocType(QualType T) {
246 return T->isAnyPointerType() || T->isBlockPointerType() ||
247 T->isReferenceType();
251 //==------------------------------------------------------------------------==//
252 // Subclasses of NonLoc.
253 //==------------------------------------------------------------------------==//
257 enum Kind { ConcreteIntKind, SymbolValKind,
258 LocAsIntegerKind, CompoundValKind, LazyCompoundValKind };
260 /// \brief Represents symbolic expression.
261 class SymbolVal : public NonLoc {
263 SymbolVal(SymbolRef sym) : NonLoc(SymbolValKind, sym) {}
265 SymbolRef getSymbol() const {
266 return (const SymExpr*) Data;
269 bool isExpression() {
270 return !isa<SymbolData>(getSymbol());
273 static inline bool classof(const SVal* V) {
274 return V->getBaseKind() == NonLocKind &&
275 V->getSubKind() == SymbolValKind;
278 static inline bool classof(const NonLoc* V) {
279 return V->getSubKind() == SymbolValKind;
283 /// \brief Value representing integer constant.
284 class ConcreteInt : public NonLoc {
286 explicit ConcreteInt(const llvm::APSInt& V) : NonLoc(ConcreteIntKind, &V) {}
288 const llvm::APSInt& getValue() const {
289 return *static_cast<const llvm::APSInt*>(Data);
292 // Transfer functions for binary/unary operations on ConcreteInts.
293 SVal evalBinOp(SValBuilder &svalBuilder, BinaryOperator::Opcode Op,
294 const ConcreteInt& R) const;
296 ConcreteInt evalComplement(SValBuilder &svalBuilder) const;
298 ConcreteInt evalMinus(SValBuilder &svalBuilder) const;
300 // Implement isa<T> support.
301 static inline bool classof(const SVal* V) {
302 return V->getBaseKind() == NonLocKind &&
303 V->getSubKind() == ConcreteIntKind;
306 static inline bool classof(const NonLoc* V) {
307 return V->getSubKind() == ConcreteIntKind;
311 class LocAsInteger : public NonLoc {
312 friend class ento::SValBuilder;
314 explicit LocAsInteger(const std::pair<SVal, uintptr_t>& data) :
315 NonLoc(LocAsIntegerKind, &data) {
316 assert (isa<Loc>(data.first));
322 const std::pair<SVal, uintptr_t> *D =
323 static_cast<const std::pair<SVal, uintptr_t> *>(Data);
324 return cast<Loc>(D->first);
327 const Loc& getPersistentLoc() const {
328 const std::pair<SVal, uintptr_t> *D =
329 static_cast<const std::pair<SVal, uintptr_t> *>(Data);
330 const SVal& V = D->first;
334 unsigned getNumBits() const {
335 const std::pair<SVal, uintptr_t> *D =
336 static_cast<const std::pair<SVal, uintptr_t> *>(Data);
340 // Implement isa<T> support.
341 static inline bool classof(const SVal* V) {
342 return V->getBaseKind() == NonLocKind &&
343 V->getSubKind() == LocAsIntegerKind;
346 static inline bool classof(const NonLoc* V) {
347 return V->getSubKind() == LocAsIntegerKind;
351 class CompoundVal : public NonLoc {
352 friend class ento::SValBuilder;
354 explicit CompoundVal(const CompoundValData* D) : NonLoc(CompoundValKind, D) {}
357 const CompoundValData* getValue() const {
358 return static_cast<const CompoundValData*>(Data);
361 typedef llvm::ImmutableList<SVal>::iterator iterator;
362 iterator begin() const;
363 iterator end() const;
365 static bool classof(const SVal* V) {
366 return V->getBaseKind() == NonLocKind && V->getSubKind() == CompoundValKind;
369 static bool classof(const NonLoc* V) {
370 return V->getSubKind() == CompoundValKind;
374 class LazyCompoundVal : public NonLoc {
375 friend class ento::SValBuilder;
377 explicit LazyCompoundVal(const LazyCompoundValData *D)
378 : NonLoc(LazyCompoundValKind, D) {}
380 const LazyCompoundValData *getCVData() const {
381 return static_cast<const LazyCompoundValData*>(Data);
383 const void *getStore() const;
384 const TypedRegion *getRegion() const;
386 static bool classof(const SVal *V) {
387 return V->getBaseKind() == NonLocKind &&
388 V->getSubKind() == LazyCompoundValKind;
390 static bool classof(const NonLoc *V) {
391 return V->getSubKind() == LazyCompoundValKind;
395 } // end namespace ento::nonloc
397 //==------------------------------------------------------------------------==//
398 // Subclasses of Loc.
399 //==------------------------------------------------------------------------==//
403 enum Kind { GotoLabelKind, MemRegionKind, ConcreteIntKind };
405 class GotoLabel : public Loc {
407 explicit GotoLabel(LabelDecl *Label) : Loc(GotoLabelKind, Label) {}
409 const LabelDecl *getLabel() const {
410 return static_cast<const LabelDecl*>(Data);
413 static inline bool classof(const SVal* V) {
414 return V->getBaseKind() == LocKind && V->getSubKind() == GotoLabelKind;
417 static inline bool classof(const Loc* V) {
418 return V->getSubKind() == GotoLabelKind;
423 class MemRegionVal : public Loc {
425 explicit MemRegionVal(const MemRegion* r) : Loc(MemRegionKind, r) {}
427 /// \brief Get the underlining region.
428 const MemRegion* getRegion() const {
429 return static_cast<const MemRegion*>(Data);
432 /// \brief Get the underlining region and strip casts.
433 const MemRegion* stripCasts(bool StripBaseCasts = true) const;
435 template <typename REGION>
436 const REGION* getRegionAs() const {
437 return llvm::dyn_cast<REGION>(getRegion());
440 inline bool operator==(const MemRegionVal& R) const {
441 return getRegion() == R.getRegion();
444 inline bool operator!=(const MemRegionVal& R) const {
445 return getRegion() != R.getRegion();
448 // Implement isa<T> support.
449 static inline bool classof(const SVal* V) {
450 return V->getBaseKind() == LocKind &&
451 V->getSubKind() == MemRegionKind;
454 static inline bool classof(const Loc* V) {
455 return V->getSubKind() == MemRegionKind;
459 class ConcreteInt : public Loc {
461 explicit ConcreteInt(const llvm::APSInt& V) : Loc(ConcreteIntKind, &V) {}
463 const llvm::APSInt& getValue() const {
464 return *static_cast<const llvm::APSInt*>(Data);
467 // Transfer functions for binary/unary operations on ConcreteInts.
468 SVal evalBinOp(BasicValueFactory& BasicVals, BinaryOperator::Opcode Op,
469 const ConcreteInt& R) const;
471 // Implement isa<T> support.
472 static inline bool classof(const SVal* V) {
473 return V->getBaseKind() == LocKind &&
474 V->getSubKind() == ConcreteIntKind;
477 static inline bool classof(const Loc* V) {
478 return V->getSubKind() == ConcreteIntKind;
482 } // end ento::loc namespace
483 } // end GR namespace
485 } // end clang namespace
488 static inline raw_ostream &operator<<(raw_ostream &os,
489 clang::ento::SVal V) {
494 } // end llvm namespace