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
140
141
142
143
144
145
146
147
148
|
/********************* */
/*! \file ceg_instantiator.h
** \verbatim
** Original author: Andrew Reynolds
** Major contributors: none
** Minor contributors (to current version): none
** This file is part of the CVC4 project.
** Copyright (c) 2009-2014 New York University and The University of Iowa
** See the file COPYING in the top-level source directory for licensing
** information.\endverbatim
**
** \brief counterexample-guided quantifier instantiation
**/
#include "cvc4_private.h"
#ifndef __CVC4__CEG_INSTANTIATOR_H
#define __CVC4__CEG_INSTANTIATOR_H
#include "theory/quantifiers_engine.h"
#include "util/statistics_registry.h"
namespace CVC4 {
namespace theory {
namespace arith {
class TheoryArith;
}
namespace quantifiers {
class CegqiOutput {
public:
virtual ~CegqiOutput() {}
virtual bool addInstantiation( std::vector< Node >& subs ) = 0;
virtual bool isEligibleForInstantiation( Node n ) = 0;
virtual bool addLemma( Node lem ) = 0;
};
class CegInstantiator {
private:
QuantifiersEngine * d_qe;
CegqiOutput * d_out;
//constants
Node d_zero;
Node d_one;
Node d_true;
bool d_use_vts_delta;
bool d_use_vts_inf;
Node d_vts_sym[2];
//program variable contains cache
std::map< Node, std::map< Node, bool > > d_prog_var;
std::map< Node, bool > d_inelig;
//current assertions
std::map< TheoryId, std::vector< Node > > d_curr_asserts;
std::map< Node, std::vector< Node > > d_curr_eqc;
std::map< TypeNode, std::vector< Node > > d_curr_type_eqc;
//auxiliary variables
std::vector< Node > d_aux_vars;
//literals to equalities for aux vars
std::map< Node, std::map< Node, Node > > d_aux_eq;
//the CE variables
std::vector< Node > d_vars;
//index of variables reported in instantiation
std::vector< unsigned > d_var_order_index;
//atoms of the CE lemma
bool d_is_nested_quant;
std::vector< Node > d_ce_atoms;
private:
//collect atoms
void collectCeAtoms( Node n, std::map< Node, bool >& visited );
//for adding instantiations during check
void computeProgVars( Node n );
//solved form, involves substitution with coefficients
class SolvedForm {
public:
std::vector< Node > d_subs;
std::vector< Node > d_coeff;
std::vector< Node > d_has_coeff;
void copy( SolvedForm& sf ){
d_subs.insert( d_subs.end(), sf.d_subs.begin(), sf.d_subs.end() );
d_coeff.insert( d_coeff.end(), sf.d_coeff.begin(), sf.d_coeff.end() );
d_has_coeff.insert( d_has_coeff.end(), sf.d_has_coeff.begin(), sf.d_has_coeff.end() );
}
void push_back( Node pv, Node n, Node pv_coeff ){
d_subs.push_back( n );
d_coeff.push_back( pv_coeff );
if( !pv_coeff.isNull() ){
d_has_coeff.push_back( pv );
}
}
void pop_back( Node pv, Node n, Node pv_coeff ){
d_subs.pop_back();
d_coeff.pop_back();
if( !pv_coeff.isNull() ){
d_has_coeff.pop_back();
}
}
};
/*
class MbpBound {
public:
Node d_bound;
Node d_coeff;
Node d_vts_coeff[2];
Node d_lit;
};
*/
// effort=0 : do not use model value, 1: use model value, 2: one must use model value
bool addInstantiation( SolvedForm& sf, SolvedForm& ssf, std::vector< Node >& vars,
std::vector< int >& btyp, Node theta, unsigned i, unsigned effort,
std::map< Node, Node >& cons, std::vector< Node >& curr_var );
bool addInstantiationInc( Node n, Node pv, Node pv_coeff, int bt, SolvedForm& sf, SolvedForm& ssf, std::vector< Node >& vars,
std::vector< int >& btyp, Node theta, unsigned i, unsigned effort,
std::map< Node, Node >& cons, std::vector< Node >& curr_var );
bool addInstantiationCoeff( SolvedForm& sf,
std::vector< Node >& vars, std::vector< int >& btyp,
unsigned j, std::map< Node, Node >& cons );
bool addInstantiation( std::vector< Node >& subs, std::vector< Node >& vars, std::map< Node, Node >& cons );
Node constructInstantiation( Node n, std::map< Node, Node >& subs_map, std::map< Node, Node >& cons );
Node applySubstitution( TypeNode tn, Node n, SolvedForm& sf, std::vector< Node >& vars, Node& pv_coeff, bool try_coeff = true ) {
return applySubstitution( tn, n, sf.d_subs, sf.d_coeff, sf.d_has_coeff, vars, pv_coeff, try_coeff );
}
Node applySubstitution( TypeNode tn, Node n, std::vector< Node >& subs, std::vector< Node >& coeff, std::vector< Node >& has_coeff,
std::vector< Node >& vars, Node& pv_coeff, bool try_coeff = true );
Node getModelBasedProjectionValue( Node e, Node t, bool isLower, Node c, Node me, Node mt, Node theta, Node inf_coeff, Node delta_coeff );
void processAssertions();
void addToAuxVarSubstitution( std::vector< Node >& subs_lhs, std::vector< Node >& subs_rhs, Node l, Node r );
//get model value
Node getModelValue( Node n );
private:
int isolate( Node v, Node atom, Node & veq_c, Node & val, Node& vts_coeff_inf, Node& vts_coeff_delta );
public:
CegInstantiator( QuantifiersEngine * qe, CegqiOutput * out, bool use_vts_delta = true, bool use_vts_inf = true );
//check : add instantiations based on valuation of d_vars
bool check();
//presolve for quantified formula
void presolve( Node q );
//register the counterexample lemma (stored in lems), modify vector
void registerCounterexampleLemma( std::vector< Node >& lems, std::vector< Node >& ce_vars );
};
}
}
}
#endif
|
