1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
|
/********************* */
/*! \file substitutions.h
** \verbatim
** Original author: mdeters
** Major contributors: dejan
** Minor contributors (to current version): none
** This file is part of the CVC4 prototype.
** Copyright (c) 2009, 2010, 2011 The Analysis of Computer Systems Group (ACSys)
** Courant Institute of Mathematical Sciences
** New York University
** See the file COPYING in the top-level source directory for licensing
** information.\endverbatim
**
** \brief A substitution mapping for theory simplification
**
** A substitution mapping for theory simplification.
**/
#include "cvc4_private.h"
#ifndef __CVC4__THEORY__SUBSTITUTIONS_H
#define __CVC4__THEORY__SUBSTITUTIONS_H
#include <utility>
#include <vector>
#include <algorithm>
#include "expr/node.h"
#include "context/context.h"
#include "context/cdo.h"
#include "context/cdmap.h"
#include "util/hash.h"
namespace CVC4 {
namespace theory {
/**
* The type for the Substitutions mapping output by
* Theory::simplify(), TheoryEngine::simplify(), and
* Valuation::simplify(). This is in its own header to
* avoid circular dependences between those three.
*
* This map is context-dependent.
*/
class SubstitutionMap {
public:
typedef context::CDMap<Node, Node, NodeHashFunction> NodeMap;
private:
typedef std::hash_map<Node, Node, NodeHashFunction> NodeCache;
/** The context within which this SubstitutionMap was constructed. */
context::Context* d_context;
/** The variables, in order of addition */
NodeMap d_substitutions;
/** Cache of the already performed substitutions */
NodeCache d_substitutionCache;
/** Has the cache been invalidated? */
bool d_cacheInvalidated;
/** Internal method that performs substitution */
Node internalSubstitute(TNode t, NodeCache& substitutionCache);
/** Helper class to invalidate cache on user pop */
class CacheInvalidator : public context::ContextNotifyObj {
bool& d_cacheInvalidated;
public:
CacheInvalidator(context::Context* context, bool& cacheInvalidated) :
context::ContextNotifyObj(context),
d_cacheInvalidated(cacheInvalidated) {
}
void notify() {
d_cacheInvalidated = true;
}
};/* class SubstitutionMap::CacheInvalidator */
/**
* This object is notified on user pop and marks the SubstitutionMap's
* cache as invalidated.
*/
CacheInvalidator d_cacheInvalidator;
public:
SubstitutionMap(context::Context* context) :
d_context(context),
d_substitutions(context),
d_substitutionCache(),
d_cacheInvalidated(false),
d_cacheInvalidator(context, d_cacheInvalidated) {
}
/**
* Adds a substitution from x to t
*/
void addSubstitution(TNode x, TNode t, bool invalidateCache = true);
/**
* Apply the substitutions to the node.
*/
Node apply(TNode t);
/**
* Apply the substitutions to the node.
*/
Node apply(TNode t) const {
return const_cast<SubstitutionMap*>(this)->apply(t);
}
// NOTE [MGD]: removed clear() and swap() from the interface
// when this data structure became context-dependent
// because they weren't used---and it's not clear how they
// should // best interact with cache invalidation on context
// pops.
/**
* Print to the output stream
*/
void print(std::ostream& out) const;
};
inline std::ostream& operator << (std::ostream& out, const SubstitutionMap& subst) {
subst.print(out);
return out;
}
}/* CVC4::theory namespace */
}/* CVC4 namespace */
#endif /* __CVC4__THEORY__SUBSTITUTIONS_H */
|
