1 //=== Iterator.h - Common functions for iterator checkers. ---------*- C++ -*-//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Defines common functions to be used by the itertor checkers .
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_LIB_STATICANALYZER_CHECKERS_ITERATOR_H
14 #define LLVM_CLANG_LIB_STATICANALYZER_CHECKERS_ITERATOR_H
15 
16 #include "clang/StaticAnalyzer/Core/PathSensitive/DynamicType.h"
17 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
18 #include "clang/StaticAnalyzer/Core/PathSensitive/SymExpr.h"
19 
20 namespace clang {
21 namespace ento {
22 namespace iterator {
23 
24 // Abstract position of an iterator. This helps to handle all three kinds
25 // of operators in a common way by using a symbolic position.
26 struct IteratorPosition {
27 private:
28 
29   // Container the iterator belongs to
30   const MemRegion *Cont;
31 
32   // Whether iterator is valid
33   const bool Valid;
34 
35   // Abstract offset
36   const SymbolRef Offset;
37 
38   IteratorPosition(const MemRegion *C, bool V, SymbolRef Of)
39       : Cont(C), Valid(V), Offset(Of) {}
40 
41 public:
42   const MemRegion *getContainer() const { return Cont; }
43   bool isValid() const { return Valid; }
44   SymbolRef getOffset() const { return Offset; }
45 
46   IteratorPosition invalidate() const {
47     return IteratorPosition(Cont, false, Offset);
48   }
49 
50   static IteratorPosition getPosition(const MemRegion *C, SymbolRef Of) {
51     return IteratorPosition(C, true, Of);
52   }
53 
54   IteratorPosition setTo(SymbolRef NewOf) const {
55     return IteratorPosition(Cont, Valid, NewOf);
56   }
57 
58   IteratorPosition reAssign(const MemRegion *NewCont) const {
59     return IteratorPosition(NewCont, Valid, Offset);
60   }
61 
62   bool operator==(const IteratorPosition &X) const {
63     return Cont == X.Cont && Valid == X.Valid && Offset == X.Offset;
64   }
65 
66   bool operator!=(const IteratorPosition &X) const { return !(*this == X); }
67 
68   void Profile(llvm::FoldingSetNodeID &ID) const {
69     ID.AddPointer(Cont);
70     ID.AddInteger(Valid);
71     ID.Add(Offset);
72   }
73 };
74 
75 // Structure to record the symbolic begin and end position of a container
76 struct ContainerData {
77 private:
78   const SymbolRef Begin, End;
79 
80   ContainerData(SymbolRef B, SymbolRef E) : Begin(B), End(E) {}
81 
82 public:
83   static ContainerData fromBegin(SymbolRef B) {
84     return ContainerData(B, nullptr);
85   }
86 
87   static ContainerData fromEnd(SymbolRef E) {
88     return ContainerData(nullptr, E);
89   }
90 
91   SymbolRef getBegin() const { return Begin; }
92   SymbolRef getEnd() const { return End; }
93 
94   ContainerData newBegin(SymbolRef B) const { return ContainerData(B, End); }
95 
96   ContainerData newEnd(SymbolRef E) const { return ContainerData(Begin, E); }
97 
98   bool operator==(const ContainerData &X) const {
99     return Begin == X.Begin && End == X.End;
100   }
101 
102   bool operator!=(const ContainerData &X) const { return !(*this == X); }
103 
104   void Profile(llvm::FoldingSetNodeID &ID) const {
105     ID.Add(Begin);
106     ID.Add(End);
107   }
108 };
109 
110 class IteratorSymbolMap {};
111 class IteratorRegionMap {};
112 class ContainerMap {};
113 
114 using IteratorSymbolMapTy =
115   CLANG_ENTO_PROGRAMSTATE_MAP(SymbolRef, IteratorPosition);
116 using IteratorRegionMapTy =
117   CLANG_ENTO_PROGRAMSTATE_MAP(const MemRegion *, IteratorPosition);
118 using ContainerMapTy =
119   CLANG_ENTO_PROGRAMSTATE_MAP(const MemRegion *, ContainerData);
120 
121 } // namespace iterator
122 
123 template<>
124 struct ProgramStateTrait<iterator::IteratorSymbolMap>
125   : public ProgramStatePartialTrait<iterator::IteratorSymbolMapTy> {
126   static void *GDMIndex() { static int Index; return &Index; }
127 };
128 
129 template<>
130 struct ProgramStateTrait<iterator::IteratorRegionMap>
131   : public ProgramStatePartialTrait<iterator::IteratorRegionMapTy> {
132   static void *GDMIndex() { static int Index; return &Index; }
133 };
134 
135 template<>
136 struct ProgramStateTrait<iterator::ContainerMap>
137   : public ProgramStatePartialTrait<iterator::ContainerMapTy> {
138   static void *GDMIndex() { static int Index; return &Index; }
139 };
140 
141 namespace iterator {
142 
143 bool isIteratorType(const QualType &Type);
144 bool isIterator(const CXXRecordDecl *CRD);
145 bool isComparisonOperator(OverloadedOperatorKind OK);
146 bool isInsertCall(const FunctionDecl *Func);
147 bool isEraseCall(const FunctionDecl *Func);
148 bool isEraseAfterCall(const FunctionDecl *Func);
149 bool isEmplaceCall(const FunctionDecl *Func);
150 bool isAccessOperator(OverloadedOperatorKind OK);
151 bool isAccessOperator(UnaryOperatorKind OK);
152 bool isAccessOperator(BinaryOperatorKind OK);
153 bool isDereferenceOperator(OverloadedOperatorKind OK);
154 bool isDereferenceOperator(UnaryOperatorKind OK);
155 bool isDereferenceOperator(BinaryOperatorKind OK);
156 bool isIncrementOperator(OverloadedOperatorKind OK);
157 bool isIncrementOperator(UnaryOperatorKind OK);
158 bool isDecrementOperator(OverloadedOperatorKind OK);
159 bool isDecrementOperator(UnaryOperatorKind OK);
160 bool isRandomIncrOrDecrOperator(OverloadedOperatorKind OK);
161 bool isRandomIncrOrDecrOperator(BinaryOperatorKind OK);
162 const ContainerData *getContainerData(ProgramStateRef State,
163                                       const MemRegion *Cont);
164 const IteratorPosition *getIteratorPosition(ProgramStateRef State, SVal Val);
165 ProgramStateRef setIteratorPosition(ProgramStateRef State, SVal Val,
166                                     const IteratorPosition &Pos);
167 ProgramStateRef createIteratorPosition(ProgramStateRef State, SVal Val,
168                                        const MemRegion *Cont, const Stmt *S,
169                                        const LocationContext *LCtx,
170                                        unsigned blockCount);
171 ProgramStateRef advancePosition(ProgramStateRef State, SVal Iter,
172                                 OverloadedOperatorKind Op, SVal Distance);
173 ProgramStateRef assumeNoOverflow(ProgramStateRef State, SymbolRef Sym,
174                                  long Scale);
175 bool compare(ProgramStateRef State, SymbolRef Sym1, SymbolRef Sym2,
176              BinaryOperator::Opcode Opc);
177 bool compare(ProgramStateRef State, NonLoc NL1, NonLoc NL2,
178              BinaryOperator::Opcode Opc);
179 
180 } // namespace iterator
181 } // namespace ento
182 } // namespace clang
183 
184 #endif
185