clang  3.7.0
SValBuilder.h
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1 // SValBuilder.h - Construction of SVals from evaluating 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 SValBuilder, a class that defines the interface for
11 // "symbolical evaluators" which construct an SVal from an expression.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_SVALBUILDER_H
16 #define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_SVALBUILDER_H
17 
18 #include "clang/AST/ASTContext.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/AST/ExprObjC.h"
24 
25 namespace clang {
26 
27 class CXXBoolLiteralExpr;
28 
29 namespace ento {
30 
31 class SValBuilder {
32  virtual void anchor();
33 protected:
35 
36  /// Manager of APSInt values.
38 
39  /// Manages the creation of symbols.
41 
42  /// Manages the creation of memory regions.
44 
46 
47  /// The scalar type to use for array indices.
49 
50  /// The width of the scalar type used for array indices.
51  const unsigned ArrayIndexWidth;
52 
53  virtual SVal evalCastFromNonLoc(NonLoc val, QualType castTy) = 0;
54  virtual SVal evalCastFromLoc(Loc val, QualType castTy) = 0;
55 
56 public:
57  // FIXME: Make these protected again once RegionStoreManager correctly
58  // handles loads from different bound value types.
59  virtual SVal dispatchCast(SVal val, QualType castTy) = 0;
60 
61 public:
62  SValBuilder(llvm::BumpPtrAllocator &alloc, ASTContext &context,
63  ProgramStateManager &stateMgr)
64  : Context(context), BasicVals(context, alloc),
65  SymMgr(context, BasicVals, alloc),
66  MemMgr(context, alloc),
67  StateMgr(stateMgr),
68  ArrayIndexTy(context.IntTy),
69  ArrayIndexWidth(context.getTypeSize(ArrayIndexTy)) {}
70 
71  virtual ~SValBuilder() {}
72 
73  bool haveSameType(const SymExpr *Sym1, const SymExpr *Sym2) {
74  return haveSameType(Sym1->getType(), Sym2->getType());
75  }
76 
77  bool haveSameType(QualType Ty1, QualType Ty2) {
78  // FIXME: Remove the second disjunct when we support symbolic
79  // truncation/extension.
80  return (Context.getCanonicalType(Ty1) == Context.getCanonicalType(Ty2) ||
83  }
84 
85  SVal evalCast(SVal val, QualType castTy, QualType originalType);
86 
87  virtual SVal evalMinus(NonLoc val) = 0;
88 
89  virtual SVal evalComplement(NonLoc val) = 0;
90 
91  /// Create a new value which represents a binary expression with two non-
92  /// location operands.
94  NonLoc lhs, NonLoc rhs, QualType resultTy) = 0;
95 
96  /// Create a new value which represents a binary expression with two memory
97  /// location operands.
99  Loc lhs, Loc rhs, QualType resultTy) = 0;
100 
101  /// Create a new value which represents a binary expression with a memory
102  /// location and non-location operands. For example, this would be used to
103  /// evaluate a pointer arithmetic operation.
105  Loc lhs, NonLoc rhs, QualType resultTy) = 0;
106 
107  /// Evaluates a given SVal. If the SVal has only one possible (integer) value,
108  /// that value is returned. Otherwise, returns NULL.
109  virtual const llvm::APSInt *getKnownValue(ProgramStateRef state, SVal val) = 0;
110 
111  /// Constructs a symbolic expression for two non-location values.
113  NonLoc lhs, NonLoc rhs, QualType resultTy);
114 
116  SVal lhs, SVal rhs, QualType type);
117 
120 
122  const ASTContext &getContext() const { return Context; }
123 
125 
127  return Context.getLangOpts().CPlusPlus ? Context.BoolTy : Context.IntTy;
128  }
129 
131  return ArrayIndexTy;
132  }
133 
136 
138  const SymbolManager &getSymbolManager() const { return SymMgr; }
139 
141  const MemRegionManager &getRegionManager() const { return MemMgr; }
142 
143  // Forwarding methods to SymbolManager.
144 
146  const LocationContext *LCtx,
147  QualType type,
148  unsigned visitCount,
149  const void *symbolTag = nullptr) {
150  return SymMgr.conjureSymbol(stmt, LCtx, type, visitCount, symbolTag);
151  }
152 
154  const LocationContext *LCtx,
155  unsigned visitCount,
156  const void *symbolTag = nullptr) {
157  return SymMgr.conjureSymbol(expr, LCtx, visitCount, symbolTag);
158  }
159 
160  /// Construct an SVal representing '0' for the specified type.
162 
163  /// Make a unique symbol for value of region.
165 
166  /// \brief Create a new symbol with a unique 'name'.
167  ///
168  /// We resort to conjured symbols when we cannot construct a derived symbol.
169  /// The advantage of symbols derived/built from other symbols is that we
170  /// preserve the relation between related(or even equivalent) expressions, so
171  /// conjured symbols should be used sparingly.
172  DefinedOrUnknownSVal conjureSymbolVal(const void *symbolTag,
173  const Expr *expr,
174  const LocationContext *LCtx,
175  unsigned count);
176  DefinedOrUnknownSVal conjureSymbolVal(const void *symbolTag,
177  const Expr *expr,
178  const LocationContext *LCtx,
179  QualType type,
180  unsigned count);
181 
183  const LocationContext *LCtx,
184  QualType type,
185  unsigned visitCount);
186  /// \brief Conjure a symbol representing heap allocated memory region.
187  ///
188  /// Note, the expression should represent a location.
190  const LocationContext *LCtx,
191  unsigned Count);
192 
194  SymbolRef parentSymbol, const TypedValueRegion *region);
195 
197  const void *symbolTag, const MemRegion *region,
198  const Expr *expr, QualType type, unsigned count);
199 
201 
202  DefinedSVal getBlockPointer(const BlockDecl *block, CanQualType locTy,
203  const LocationContext *locContext,
204  unsigned blockCount);
205 
206  /// Returns the value of \p E, if it can be determined in a non-path-sensitive
207  /// manner.
208  ///
209  /// If \p E is not a constant or cannot be modeled, returns \c None.
211 
214  }
215 
217  const TypedValueRegion *region) {
219  BasicVals.getLazyCompoundValData(store, region));
220  }
221 
223  return nonloc::ConcreteInt(BasicVals.getValue(0, ArrayIndexTy));
224  }
225 
226  NonLoc makeArrayIndex(uint64_t idx) {
227  return nonloc::ConcreteInt(BasicVals.getValue(idx, ArrayIndexTy));
228  }
229 
231 
233  return nonloc::ConcreteInt(
234  BasicVals.getValue(integer->getValue(),
236  }
237 
239  return makeTruthVal(boolean->getValue(), boolean->getType());
240  }
241 
243 
244  nonloc::ConcreteInt makeIntVal(const llvm::APSInt& integer) {
245  return nonloc::ConcreteInt(BasicVals.getValue(integer));
246  }
247 
248  loc::ConcreteInt makeIntLocVal(const llvm::APSInt &integer) {
249  return loc::ConcreteInt(BasicVals.getValue(integer));
250  }
251 
252  NonLoc makeIntVal(const llvm::APInt& integer, bool isUnsigned) {
253  return nonloc::ConcreteInt(BasicVals.getValue(integer, isUnsigned));
254  }
255 
256  DefinedSVal makeIntVal(uint64_t integer, QualType type) {
257  if (Loc::isLocType(type))
258  return loc::ConcreteInt(BasicVals.getValue(integer, type));
259 
260  return nonloc::ConcreteInt(BasicVals.getValue(integer, type));
261  }
262 
263  NonLoc makeIntVal(uint64_t integer, bool isUnsigned) {
264  return nonloc::ConcreteInt(BasicVals.getIntValue(integer, isUnsigned));
265  }
266 
267  NonLoc makeIntValWithPtrWidth(uint64_t integer, bool isUnsigned) {
268  return nonloc::ConcreteInt(
269  BasicVals.getIntWithPtrWidth(integer, isUnsigned));
270  }
271 
272  NonLoc makeLocAsInteger(Loc loc, unsigned bits) {
274  }
275 
277  const llvm::APSInt& rhs, QualType type);
278 
279  NonLoc makeNonLoc(const llvm::APSInt& rhs, BinaryOperator::Opcode op,
280  const SymExpr *lhs, QualType type);
281 
283  const SymExpr *rhs, QualType type);
284 
285  /// \brief Create a NonLoc value for cast.
286  NonLoc makeNonLoc(const SymExpr *operand, QualType fromTy, QualType toTy);
287 
290  }
291 
294  }
295 
298  }
299 
302  }
303 
304  Loc makeLoc(const MemRegion* region) {
305  return loc::MemRegionVal(region);
306  }
307 
309  return loc::GotoLabel(expr->getLabel());
310  }
311 
312  Loc makeLoc(const llvm::APSInt& integer) {
313  return loc::ConcreteInt(BasicVals.getValue(integer));
314  }
315 
316  /// Return a memory region for the 'this' object reference.
318  const StackFrameContext *SFC);
319 
320  /// Return a memory region for the 'this' object reference.
322  const StackFrameContext *SFC);
323 };
324 
325 SValBuilder* createSimpleSValBuilder(llvm::BumpPtrAllocator &alloc,
326  ASTContext &context,
327  ProgramStateManager &stateMgr);
328 
329 } // end GR namespace
330 
331 } // end clang namespace
332 
333 #endif
Defines the clang::ASTContext interface.
const internal::VariadicDynCastAllOfMatcher< Stmt, Expr > expr
Matches expressions.
Definition: ASTMatchers.h:1110
TypedValueRegion - An abstract class representing regions having a typed value.
Definition: MemRegion.h:498
nonloc::ConcreteInt makeIntVal(const IntegerLiteral *integer)
Definition: SValBuilder.h:232
DefinedSVal getBlockPointer(const BlockDecl *block, CanQualType locTy, const LocationContext *locContext, unsigned blockCount)
SymbolManager & getSymbolManager()
Definition: SValBuilder.h:137
MemRegion - The root abstract class for all memory regions.
Definition: MemRegion.h:77
QualType getArrayIndexType() const
Definition: SValBuilder.h:130
const CompoundValData * getCompoundValData(QualType T, llvm::ImmutableList< SVal > Vals)
SValBuilder * createSimpleSValBuilder(llvm::BumpPtrAllocator &alloc, ASTContext &context, ProgramStateManager &stateMgr)
const internal::VariadicAllOfMatcher< Stmt > stmt
Matches statements.
Definition: ASTMatchers.h:826
SVal makeSymExprValNN(ProgramStateRef state, BinaryOperator::Opcode op, NonLoc lhs, NonLoc rhs, QualType resultTy)
Constructs a symbolic expression for two non-location values.
ProgramStateManager & StateMgr
Definition: SValBuilder.h:45
SVal evalCast(SVal val, QualType castTy, QualType originalType)
Value representing integer constant.
Definition: SVals.h:339
MemRegionManager MemMgr
Manages the creation of memory regions.
Definition: SValBuilder.h:43
const SymbolManager & getSymbolManager() const
Definition: SValBuilder.h:138
const llvm::APSInt & getTruthValue(bool b, QualType T)
virtual SVal dispatchCast(SVal val, QualType castTy)=0
loc::MemRegionVal getCXXThis(const CXXMethodDecl *D, const StackFrameContext *SFC)
Return a memory region for the 'this' object reference.
NonLoc makeNonLoc(const SymExpr *lhs, BinaryOperator::Opcode op, const llvm::APSInt &rhs, QualType type)
Definition: SValBuilder.cpp:44
NonLoc makeArrayIndex(uint64_t idx)
Definition: SValBuilder.h:226
BasicValueFactory BasicVals
Manager of APSInt values.
Definition: SValBuilder.h:37
Symbolic value. These values used to capture symbolic execution of the program.
Definition: SymbolManager.h:42
virtual SVal evalCastFromNonLoc(NonLoc val, QualType castTy)=0
virtual SVal evalBinOpLN(ProgramStateRef state, BinaryOperator::Opcode op, Loc lhs, NonLoc rhs, QualType resultTy)=0
MemRegionManager & getRegionManager()
Definition: SValBuilder.h:140
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:89
DefinedOrUnknownSVal getDerivedRegionValueSymbolVal(SymbolRef parentSymbol, const TypedValueRegion *region)
const SymbolicRegion * getSymbolicRegion(SymbolRef Sym)
Retrieve or create a "symbolic" memory region.
Definition: MemRegion.cpp:941
static bool isLocType(QualType T)
Definition: SVals.h:291
BinaryOperatorKind
const LangOptions & getLangOpts() const
Definition: ASTContext.h:533
DefinedOrUnknownSVal getRegionValueSymbolVal(const TypedValueRegion *region)
Make a unique symbol for value of region.
Definition: SValBuilder.cpp:95
Loc makeLoc(const MemRegion *region)
Definition: SValBuilder.h:304
Loc makeLoc(const AddrLabelExpr *expr)
Definition: SValBuilder.h:308
loc::ConcreteInt makeIntLocVal(const llvm::APSInt &integer)
Definition: SValBuilder.h:248
NonLoc makeCompoundVal(QualType type, llvm::ImmutableList< SVal > vals)
Definition: SValBuilder.h:212
DefinedSVal getFunctionPointer(const FunctionDecl *func)
NonLoc makeIntValWithPtrWidth(uint64_t integer, bool isUnsigned)
Definition: SValBuilder.h:267
bool haveSameType(QualType Ty1, QualType Ty2)
Definition: SValBuilder.h:77
const llvm::APSInt & getIntValue(uint64_t X, bool isUnsigned)
virtual QualType getType() const =0
llvm::APInt getValue() const
Definition: Expr.h:1262
nonloc::ConcreteInt makeBoolVal(const ObjCBoolLiteralExpr *boolean)
Definition: SValBuilder.h:238
Loc makeLoc(SymbolRef sym)
Definition: SValBuilder.h:300
DefinedOrUnknownSVal makeZeroVal(QualType type)
Construct an SVal representing '0' for the specified type.
Definition: SValBuilder.cpp:32
virtual SVal evalMinus(NonLoc val)=0
const llvm::APSInt & getIntWithPtrWidth(uint64_t X, bool isUnsigned)
nonloc::ConcreteInt makeTruthVal(bool b)
Definition: SValBuilder.h:292
const QualType ArrayIndexTy
The scalar type to use for array indices.
Definition: SValBuilder.h:48
virtual SVal evalBinOpLL(ProgramStateRef state, BinaryOperator::Opcode op, Loc lhs, Loc rhs, QualType resultTy)=0
SVal evalBinOp(ProgramStateRef state, BinaryOperator::Opcode op, SVal lhs, SVal rhs, QualType type)
nonloc::ConcreteInt makeIntVal(const llvm::APSInt &integer)
Definition: SValBuilder.h:244
QualType getConditionType() const
Definition: SValBuilder.h:126
bool isUnsignedIntegerOrEnumerationType() const
Definition: Type.cpp:1739
NonLoc makeIntVal(uint64_t integer, bool isUnsigned)
Definition: SValBuilder.h:263
const ASTContext & getContext() const
Definition: SValBuilder.h:122
bool isIntegralOrEnumerationType() const
Determine whether this type is an integral or enumeration type.
Definition: Type.h:5476
bool getValue() const
Definition: ExprObjC.h:71
SymbolManager SymMgr
Manages the creation of symbols.
Definition: SValBuilder.h:40
DefinedOrUnknownSVal conjureSymbolVal(const void *symbolTag, const Expr *expr, const LocationContext *LCtx, unsigned count)
Create a new symbol with a unique 'name'.
virtual SVal evalCastFromLoc(Loc val, QualType castTy)=0
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:1717
ASTContext & getContext()
Definition: SValBuilder.h:121
const MemRegionManager & getRegionManager() const
Definition: SValBuilder.h:141
const BasicValueFactory & getBasicValueFactory() const
Definition: SValBuilder.h:135
const llvm::APSInt & getZeroWithPtrWidth(bool isUnsigned=true)
DefinedOrUnknownSVal getConjuredHeapSymbolVal(const Expr *E, const LocationContext *LCtx, unsigned Count)
Conjure a symbol representing heap allocated memory region.
virtual SVal evalBinOpNN(ProgramStateRef state, BinaryOperator::Opcode op, NonLoc lhs, NonLoc rhs, QualType resultTy)=0
const unsigned ArrayIndexWidth
The width of the scalar type used for array indices.
Definition: SValBuilder.h:51
AddrLabelExpr - The GNU address of label extension, representing &&label.
Definition: Expr.h:3357
QualType getType() const
Definition: Expr.h:125
const internal::VariadicAllOfMatcher< Type > type
Matches Types in the clang AST.
Definition: ASTMatchers.h:1639
NonLoc makeIntVal(const llvm::APInt &integer, bool isUnsigned)
Definition: SValBuilder.h:252
const SymbolConjured * conjureSymbol(const Stmt *stmt, const LocationContext *LCtx, QualType type, unsigned visitCount, const void *symbolTag=nullptr)
Definition: SValBuilder.h:145
NonLoc makeLocAsInteger(Loc loc, unsigned bits)
Definition: SValBuilder.h:272
ProgramStateManager & getStateManager()
Definition: SValBuilder.h:124
DefinedSVal getMetadataSymbolVal(const void *symbolTag, const MemRegion *region, const Expr *expr, QualType type, unsigned count)
CanQualType getCanonicalType(QualType T) const
Return the canonical (structural) type corresponding to the specified potentially non-canonical type ...
Definition: ASTContext.h:1855
SVal convertToArrayIndex(SVal val)
Definition: SValBuilder.cpp:76
const SymbolConjured * conjureSymbol(const Stmt *E, const LocationContext *LCtx, QualType T, unsigned VisitCount, const void *SymbolTag=nullptr)
BasicValueFactory & getBasicValueFactory()
Definition: SValBuilder.h:134
Loc makeLoc(const llvm::APSInt &integer)
Definition: SValBuilder.h:312
SValBuilder(llvm::BumpPtrAllocator &alloc, ASTContext &context, ProgramStateManager &stateMgr)
Definition: SValBuilder.h:62
LabelDecl * getLabel() const
Definition: Expr.h:3379
const std::pair< SVal, uintptr_t > & getPersistentSValWithData(const SVal &V, uintptr_t Data)
bool haveSameType(const SymExpr *Sym1, const SymExpr *Sym2)
Definition: SValBuilder.h:73
const LazyCompoundValData * getLazyCompoundValData(const StoreRef &store, const TypedValueRegion *region)
Represents a C++ struct/union/class.
Definition: DeclCXX.h:285
DefinedOrUnknownSVal evalEQ(ProgramStateRef state, DefinedOrUnknownSVal lhs, DefinedOrUnknownSVal rhs)
virtual SVal evalComplement(NonLoc val)=0
Optional< SVal > getConstantVal(const Expr *E)
const SymbolConjured * conjureSymbol(const Expr *expr, const LocationContext *LCtx, unsigned visitCount, const void *symbolTag=nullptr)
Definition: SValBuilder.h:153
virtual const llvm::APSInt * getKnownValue(ProgramStateRef state, SVal val)=0
CanQualType IntTy
Definition: ASTContext.h:825
nonloc::ConcreteInt makeTruthVal(bool b, QualType type)
Definition: SValBuilder.h:288
DefinedSVal makeIntVal(uint64_t integer, QualType type)
Definition: SValBuilder.h:256
NonLoc makeLazyCompoundVal(const StoreRef &store, const TypedValueRegion *region)
Definition: SValBuilder.h:216
A boolean literal, per ([C++ lex.bool] Boolean literals).
Definition: ExprCXX.h:434
CanQualType BoolTy
Definition: ASTContext.h:818