1 //===--- SValVisitor.h - Visitor for SVal subclasses ------------*- 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 the SValVisitor, SymExprVisitor, and MemRegionVisitor
11 //  interfaces, and also FullSValVisitor, which visits all three hierarchies.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_SVALVISITOR_H
16 #define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_SVALVISITOR_H
17 
18 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
19 #include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h"
20 #include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
21 
22 namespace clang {
23 
24 namespace ento {
25 
26 /// SValVisitor - this class implements a simple visitor for SVal
27 /// subclasses.
28 template <typename ImplClass, typename RetTy = void> class SValVisitor {
29 public:
30 
31 #define DISPATCH(NAME, CLASS) \
32   return static_cast<ImplClass *>(this)->Visit ## NAME(V.castAs<CLASS>())
33 
Visit(SVal V)34   RetTy Visit(SVal V) {
35     // Dispatch to VisitFooVal for each FooVal.
36     // Take namespaces (loc:: and nonloc::) into account.
37     switch (V.getBaseKind()) {
38 #define BASIC_SVAL(Id, Parent) case SVal::Id ## Kind: DISPATCH(Id, Id);
39 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.def"
40     case SVal::LocKind:
41       switch (V.getSubKind()) {
42 #define LOC_SVAL(Id, Parent) \
43       case loc::Id ## Kind: DISPATCH(Loc ## Id, loc :: Id);
44 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.def"
45       }
46       llvm_unreachable("Unknown Loc sub-kind!");
47     case SVal::NonLocKind:
48       switch (V.getSubKind()) {
49 #define NONLOC_SVAL(Id, Parent) \
50       case nonloc::Id ## Kind: DISPATCH(NonLoc ## Id, nonloc :: Id);
51 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.def"
52       }
53       llvm_unreachable("Unknown NonLoc sub-kind!");
54     }
55     llvm_unreachable("Unknown SVal kind!");
56   }
57 
58 #define BASIC_SVAL(Id, Parent) \
59   RetTy Visit ## Id(Id V) { DISPATCH(Parent, Id); }
60 #define ABSTRACT_SVAL(Id, Parent) \
61   BASIC_SVAL(Id, Parent)
62 #define LOC_SVAL(Id, Parent) \
63   RetTy VisitLoc ## Id(loc::Id V) { DISPATCH(Parent, Parent); }
64 #define NONLOC_SVAL(Id, Parent) \
65   RetTy VisitNonLoc ## Id(nonloc::Id V) { DISPATCH(Parent, Parent); }
66 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.def"
67 
68   // Base case, ignore it. :)
VisitSVal(SVal V)69   RetTy VisitSVal(SVal V) { return RetTy(); }
70 
71 #undef DISPATCH
72 };
73 
74 /// SymExprVisitor - this class implements a simple visitor for SymExpr
75 /// subclasses.
76 template <typename ImplClass, typename RetTy = void> class SymExprVisitor {
77 public:
78 
79 #define DISPATCH(CLASS) \
80     return static_cast<ImplClass *>(this)->Visit ## CLASS(cast<CLASS>(S))
81 
Visit(SymbolRef S)82   RetTy Visit(SymbolRef S) {
83     // Dispatch to VisitSymbolFoo for each SymbolFoo.
84     switch (S->getKind()) {
85 #define SYMBOL(Id, Parent) \
86     case SymExpr::Id ## Kind: DISPATCH(Id);
87 #include "clang/StaticAnalyzer/Core/PathSensitive/Symbols.def"
88     }
89     llvm_unreachable("Unknown SymExpr kind!");
90   }
91 
92   // If the implementation chooses not to implement a certain visit method, fall
93   // back on visiting the superclass.
94 #define SYMBOL(Id, Parent) RetTy Visit ## Id(const Id *S) { DISPATCH(Parent); }
95 #define ABSTRACT_SYMBOL(Id, Parent) SYMBOL(Id, Parent)
96 #include "clang/StaticAnalyzer/Core/PathSensitive/Symbols.def"
97 
98   // Base case, ignore it. :)
VisitSymExpr(SymbolRef S)99   RetTy VisitSymExpr(SymbolRef S) { return RetTy(); }
100 
101 #undef DISPATCH
102 };
103 
104 /// MemRegionVisitor - this class implements a simple visitor for MemRegion
105 /// subclasses.
106 template <typename ImplClass, typename RetTy = void> class MemRegionVisitor {
107 public:
108 
109 #define DISPATCH(CLASS) \
110   return static_cast<ImplClass *>(this)->Visit ## CLASS(cast<CLASS>(R))
111 
Visit(const MemRegion * R)112   RetTy Visit(const MemRegion *R) {
113     // Dispatch to VisitFooRegion for each FooRegion.
114     switch (R->getKind()) {
115 #define REGION(Id, Parent) case MemRegion::Id ## Kind: DISPATCH(Id);
116 #include "clang/StaticAnalyzer/Core/PathSensitive/Regions.def"
117     }
118     llvm_unreachable("Unknown MemRegion kind!");
119   }
120 
121   // If the implementation chooses not to implement a certain visit method, fall
122   // back on visiting the superclass.
123 #define REGION(Id, Parent) \
124   RetTy Visit ## Id(const Id *R) { DISPATCH(Parent); }
125 #define ABSTRACT_REGION(Id, Parent) \
126   REGION(Id, Parent)
127 #include "clang/StaticAnalyzer/Core/PathSensitive/Regions.def"
128 
129   // Base case, ignore it. :)
VisitMemRegion(const MemRegion * R)130   RetTy VisitMemRegion(const MemRegion *R) { return RetTy(); }
131 
132 #undef DISPATCH
133 };
134 
135 /// FullSValVisitor - a convenient mixed visitor for all three:
136 /// SVal, SymExpr and MemRegion subclasses.
137 template <typename ImplClass, typename RetTy = void>
138 class FullSValVisitor : public SValVisitor<ImplClass, RetTy>,
139                         public SymExprVisitor<ImplClass, RetTy>,
140                         public MemRegionVisitor<ImplClass, RetTy> {
141 public:
142   using SValVisitor<ImplClass, RetTy>::Visit;
143   using SymExprVisitor<ImplClass, RetTy>::Visit;
144   using MemRegionVisitor<ImplClass, RetTy>::Visit;
145 };
146 
147 } // end namespace ento
148 
149 } // end namespace clang
150 
151 #endif
152