1//== Environment.h - Map from Stmt* to Locations/Values ---------*- 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 defined the Environment and EnvironmentManager classes.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_CLANG_GR_ENVIRONMENT_H
15#define LLVM_CLANG_GR_ENVIRONMENT_H
16
17#include "clang/Analysis/AnalysisContext.h"
18#include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
19#include "llvm/ADT/ImmutableMap.h"
20
21namespace clang {
22
23class LiveVariables;
24
25namespace ento {
26
27class EnvironmentManager;
28class SValBuilder;
29
30/// An entry in the environment consists of a Stmt and an LocationContext.
31/// This allows the environment to manage context-sensitive bindings,
32/// which is essentially for modeling recursive function analysis, among
33/// other things.
34class EnvironmentEntry : public std::pair<const Stmt*,
35                                          const StackFrameContext *> {
36public:
37  EnvironmentEntry(const Stmt *s, const LocationContext *L);
38
39  const Stmt *getStmt() const { return first; }
40  const LocationContext *getLocationContext() const { return second; }
41
42  /// Profile an EnvironmentEntry for inclusion in a FoldingSet.
43  static void Profile(llvm::FoldingSetNodeID &ID,
44                      const EnvironmentEntry &E) {
45    ID.AddPointer(E.getStmt());
46    ID.AddPointer(E.getLocationContext());
47  }
48
49  void Profile(llvm::FoldingSetNodeID &ID) const {
50    Profile(ID, *this);
51  }
52};
53
54/// An immutable map from EnvironemntEntries to SVals.
55class Environment {
56private:
57  friend class EnvironmentManager;
58
59  // Type definitions.
60  typedef llvm::ImmutableMap<EnvironmentEntry, SVal> BindingsTy;
61
62  // Data.
63  BindingsTy ExprBindings;
64
65  Environment(BindingsTy eb)
66    : ExprBindings(eb) {}
67
68  SVal lookupExpr(const EnvironmentEntry &E) const;
69
70public:
71  typedef BindingsTy::iterator iterator;
72  iterator begin() const { return ExprBindings.begin(); }
73  iterator end() const { return ExprBindings.end(); }
74
75  /// Fetches the current binding of the expression in the
76  /// Environment.
77  SVal getSVal(const EnvironmentEntry &E, SValBuilder &svalBuilder) const;
78
79  /// Profile - Profile the contents of an Environment object for use
80  ///  in a FoldingSet.
81  static void Profile(llvm::FoldingSetNodeID& ID, const Environment* env) {
82    env->ExprBindings.Profile(ID);
83  }
84
85  /// Profile - Used to profile the contents of this object for inclusion
86  ///  in a FoldingSet.
87  void Profile(llvm::FoldingSetNodeID& ID) const {
88    Profile(ID, this);
89  }
90
91  bool operator==(const Environment& RHS) const {
92    return ExprBindings == RHS.ExprBindings;
93  }
94
95  void print(raw_ostream &Out, const char *NL, const char *Sep) const;
96
97private:
98  void printAux(raw_ostream &Out, bool printLocations,
99                const char *NL, const char *Sep) const;
100};
101
102class EnvironmentManager {
103private:
104  typedef Environment::BindingsTy::Factory FactoryTy;
105  FactoryTy F;
106
107public:
108  EnvironmentManager(llvm::BumpPtrAllocator& Allocator) : F(Allocator) {}
109  ~EnvironmentManager() {}
110
111  Environment getInitialEnvironment() {
112    return Environment(F.getEmptyMap());
113  }
114
115  /// Bind a symbolic value to the given environment entry.
116  Environment bindExpr(Environment Env, const EnvironmentEntry &E, SVal V,
117                       bool Invalidate);
118
119  Environment removeDeadBindings(Environment Env,
120                                 SymbolReaper &SymReaper,
121                                 ProgramStateRef state);
122};
123
124} // end GR namespace
125
126} // end clang namespace
127
128#endif
129