1 |
|
/****************************************************************************** |
2 |
|
* Top contributors (to current version): |
3 |
|
* Gereon Kremer |
4 |
|
* |
5 |
|
* This file is part of the cvc5 project. |
6 |
|
* |
7 |
|
* Copyright (c) 2009-2021 by the authors listed in the file AUTHORS |
8 |
|
* in the top-level source directory and their institutional affiliations. |
9 |
|
* All rights reserved. See the file COPYING in the top-level source |
10 |
|
* directory for licensing information. |
11 |
|
* **************************************************************************** |
12 |
|
* |
13 |
|
* Implements the proof generator for CAD. |
14 |
|
*/ |
15 |
|
|
16 |
|
#include "cvc5_private.h" |
17 |
|
|
18 |
|
#ifndef CVC5__THEORY__ARITH__NL__CAD__PROOF_GENERATOR_H |
19 |
|
#define CVC5__THEORY__ARITH__NL__CAD__PROOF_GENERATOR_H |
20 |
|
|
21 |
|
#ifdef CVC5_POLY_IMP |
22 |
|
|
23 |
|
#include <poly/polyxx.h> |
24 |
|
|
25 |
|
#include <vector> |
26 |
|
|
27 |
|
#include "expr/node.h" |
28 |
|
#include "proof/lazy_tree_proof_generator.h" |
29 |
|
#include "proof/proof_set.h" |
30 |
|
#include "theory/arith/nl/cad/cdcac_utils.h" |
31 |
|
|
32 |
|
namespace cvc5 { |
33 |
|
|
34 |
|
class ProofGenerator; |
35 |
|
|
36 |
|
namespace theory { |
37 |
|
namespace arith { |
38 |
|
namespace nl { |
39 |
|
|
40 |
|
struct VariableMapper; |
41 |
|
|
42 |
|
namespace cad { |
43 |
|
|
44 |
|
/** |
45 |
|
* This class manages the proof creation during a run of the CAD solver. |
46 |
|
* |
47 |
|
* Though it implements the ProofGenerator interface getProofFor(Node), it only |
48 |
|
* gives a proof for a single node. |
49 |
|
* |
50 |
|
* It uses a LazyTreeProofGenerator internally to manage the tree-based proof |
51 |
|
* construction. |
52 |
|
*/ |
53 |
588 |
class CADProofGenerator |
54 |
|
{ |
55 |
|
public: |
56 |
|
friend std::ostream& operator<<(std::ostream& os, |
57 |
|
const CADProofGenerator& proof); |
58 |
|
CADProofGenerator(context::Context* ctx, ProofNodeManager* pnm); |
59 |
|
|
60 |
|
/** Start a new proof in this proof generator */ |
61 |
|
void startNewProof(); |
62 |
|
/** Start a new recursive call */ |
63 |
|
void startRecursive(); |
64 |
|
/** Finish the current recursive call */ |
65 |
|
void endRecursive(); |
66 |
|
/** Start a new scope, corresponding to a guess in CDCAC */ |
67 |
|
void startScope(); |
68 |
|
/** Finish a scope and add the (generalized) sample that was refuted */ |
69 |
|
void endScope(const std::vector<Node>& args); |
70 |
|
/** Return the current proof generator */ |
71 |
|
ProofGenerator* getProofGenerator() const; |
72 |
|
|
73 |
|
/** |
74 |
|
* Calls LazyTreeProofGenerator::pruneChildren(f), but decorates the |
75 |
|
* predicate such that f only accepts the index. |
76 |
|
* @param f A Callable bool(std::size_t) |
77 |
|
*/ |
78 |
|
template <typename F> |
79 |
3 |
void pruneChildren(F&& f) |
80 |
|
{ |
81 |
3 |
d_current->pruneChildren( |
82 |
6 |
[&f](std::size_t i, const detail::TreeProofNode& tpn) { return f(i); }); |
83 |
3 |
} |
84 |
|
|
85 |
|
/** |
86 |
|
* Add a direct interval conflict as generated in getUnsatIntervals(). |
87 |
|
* Its meaning is: |
88 |
|
* over the partial assignment a, var is not in interval because p~sc~0 |
89 |
|
* and the origin of this is constraint. |
90 |
|
* |
91 |
|
* @param var The variable for which the interval is excluded |
92 |
|
* @param vm A variable mapper between cvc5 and libpoly variables |
93 |
|
* @param p The polynomial of the constraint |
94 |
|
* @param a The current partial assignment |
95 |
|
* @param sc The sign condition of the constraint |
96 |
|
* @param interval The concrete interval that is excluded |
97 |
|
* @param constraint The assumption that yields p and sc |
98 |
|
*/ |
99 |
|
void addDirect(Node var, |
100 |
|
VariableMapper& vm, |
101 |
|
const poly::Polynomial& p, |
102 |
|
const poly::Assignment& a, |
103 |
|
poly::SignCondition& sc, |
104 |
|
const poly::Interval& interval, |
105 |
|
Node constraint); |
106 |
|
|
107 |
|
/** |
108 |
|
* Constructs the (generalized) interval that is to be excluded from a |
109 |
|
* CACInterval. It should be called after the recursive call to construct the |
110 |
|
* generalized sample necessary for endScope(). |
111 |
|
* |
112 |
|
* @param var The variable for which the interval is excluded |
113 |
|
* @param i The concrete interval that is excluded |
114 |
|
* @param a The current partial assignment |
115 |
|
* @param s The sample point that is refuted for var |
116 |
|
* @param vm A variable mapper between cvc5 and libpoly variables |
117 |
|
*/ |
118 |
|
std::vector<Node> constructCell(Node var, |
119 |
|
const CACInterval& i, |
120 |
|
const poly::Assignment& a, |
121 |
|
const poly::Value& s, |
122 |
|
VariableMapper& vm); |
123 |
|
|
124 |
|
private: |
125 |
|
/** The proof node manager used for the proofs */ |
126 |
|
ProofNodeManager* d_pnm; |
127 |
|
/** The list of generated proofs */ |
128 |
|
CDProofSet<LazyTreeProofGenerator> d_proofs; |
129 |
|
/** The current proof */ |
130 |
|
LazyTreeProofGenerator* d_current; |
131 |
|
|
132 |
|
/** Constant false */ |
133 |
|
Node d_false; |
134 |
|
/** Constant zero */ |
135 |
|
Node d_zero; |
136 |
|
}; |
137 |
|
|
138 |
|
/** |
139 |
|
* Prints the underlying LazyTreeProofGenerator. Please check the documentation |
140 |
|
* of std::ostream& operator<<(std::ostream&, const LazyTreeProofGenerator&) |
141 |
|
*/ |
142 |
|
std::ostream& operator<<(std::ostream& os, const CADProofGenerator& proof); |
143 |
|
|
144 |
|
} // namespace cad |
145 |
|
} // namespace nl |
146 |
|
} // namespace arith |
147 |
|
} // namespace theory |
148 |
|
} // namespace cvc5 |
149 |
|
|
150 |
|
#endif |
151 |
|
#endif |