1//===- Environment.h - Map from Stmt* to Locations/Values -------*- 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// This file defined the Environment and EnvironmentManager classes.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_ENVIRONMENT_H
14#define LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_ENVIRONMENT_H
15
16#include "clang/Analysis/AnalysisDeclContext.h"
17#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState_Fwd.h"
18#include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
19#include "llvm/ADT/ImmutableMap.h"
20#include <utility>
21
22namespace clang {
23
24class Stmt;
25
26namespace ento {
27
28class SValBuilder;
29class SymbolReaper;
30
31/// An entry in the environment consists of a Stmt and an LocationContext.
32/// This allows the environment to manage context-sensitive bindings,
33/// which is essentially for modeling recursive function analysis, among
34/// other things.
35class EnvironmentEntry : public std::pair<const Stmt *,
36 const StackFrameContext *> {
37public:
38 EnvironmentEntry(const Stmt *s, const LocationContext *L);
39
40 const Stmt *getStmt() const { return first; }
41 const LocationContext *getLocationContext() const { return second; }
42
43 /// Profile an EnvironmentEntry for inclusion in a FoldingSet.
44 static void Profile(llvm::FoldingSetNodeID &ID,
45 const EnvironmentEntry &E) {
46 ID.AddPointer(E.getStmt());
47 ID.AddPointer(E.getLocationContext());
48 }
49
50 void Profile(llvm::FoldingSetNodeID &ID) const {
51 Profile(ID, *this);
52 }
53};
54
55/// An immutable map from EnvironemntEntries to SVals.
56class Environment {
57private:
58 friend class EnvironmentManager;
59
60 using BindingsTy = llvm::ImmutableMap<EnvironmentEntry, SVal>;
61
62 BindingsTy ExprBindings;
63
64 Environment(BindingsTy eb) : ExprBindings(eb) {}
65
66 SVal lookupExpr(const EnvironmentEntry &E) const;
67
68public:
69 using iterator = BindingsTy::iterator;
70
71 iterator begin() const { return ExprBindings.begin(); }
72 iterator end() const { return ExprBindings.end(); }
73
74 /// Fetches the current binding of the expression in the
75 /// Environment.
76 SVal getSVal(const EnvironmentEntry &E, SValBuilder &svalBuilder) const;
77
78 /// Profile - Profile the contents of an Environment object for use
79 /// in a FoldingSet.
80 static void Profile(llvm::FoldingSetNodeID& ID, const Environment* env) {
81 env->ExprBindings.Profile(ID);
82 }
83
84 /// Profile - Used to profile the contents of this object for inclusion
85 /// in a FoldingSet.
86 void Profile(llvm::FoldingSetNodeID& ID) const {
87 Profile(ID, this);
88 }
89
90 bool operator==(const Environment& RHS) const {
91 return ExprBindings == RHS.ExprBindings;
92 }
93
94 void printJson(raw_ostream &Out, const ASTContext &Ctx,
95 const LocationContext *LCtx = nullptr, const char *NL = "\n",
96 unsigned int Space = 0, bool IsDot = false) const;
97};
98
99class EnvironmentManager {
100private:
101 using FactoryTy = Environment::BindingsTy::Factory;
102
103 FactoryTy F;
104
105public:
106 EnvironmentManager(llvm::BumpPtrAllocator &Allocator) : F(Allocator) {}
107
108 Environment getInitialEnvironment() {
109 return Environment(F.getEmptyMap());
110 }
111
112 /// Bind a symbolic value to the given environment entry.
113 Environment bindExpr(Environment Env, const EnvironmentEntry &E, SVal V,
114 bool Invalidate);
115
116 Environment removeDeadBindings(Environment Env,
117 SymbolReaper &SymReaper,
118 ProgramStateRef state);
119};
120
121} // namespace ento
122
123} // namespace clang
124
125#endif // LLVM_CLANG_STATICANALYZER_CORE_PATHSENSITIVE_ENVIRONMENT_H
126