Head

GCC Code Coverage Report

Directory:	.		Exec	Total	Coverage
File:	src/theory/strings/solver_state.cpp	Lines:	101	105	96.2 %
Date:	2021-09-07	Branches:	161	342	47.1 %


/******************************************************************************
 * Top contributors (to current version):
 *   Andrew Reynolds, Tianyi Liang, Mathias Preiner
 *
 * This file is part of the cvc5 project.
 *
 * Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
 * in the top-level source directory and their institutional affiliations.
 * All rights reserved.  See the file COPYING in the top-level source
 * directory for licensing information.
 * ****************************************************************************
 *
 * Implementation of the solver state of the theory of strings.
 */

#include "theory/strings/solver_state.h"

#include "theory/rewriter.h"
#include "theory/strings/theory_strings_utils.h"
#include "theory/strings/word.h"
#include "util/rational.h"

using namespace std;
using namespace cvc5::context;
using namespace cvc5::kind;

namespace cvc5 {
namespace theory {
namespace strings {

SolverState::SolverState(Env& env, Valuation& v)
    : TheoryState(env, v),
      d_eeDisequalities(env.getContext()),
      d_pendingConflictSet(env.getContext(), false),
      d_pendingConflict(InferenceId::UNKNOWN)
{
  d_zero = NodeManager::currentNM()->mkConst(Rational(0));
  d_false = NodeManager::currentNM()->mkConst(false);
}

SolverState::~SolverState()
{
  for (std::pair<const Node, EqcInfo*>& it : d_eqcInfo)
  {
    delete it.second;
  }
}

const context::CDList<Node>& SolverState::getDisequalityList() const
{
  return d_eeDisequalities;
}

void SolverState::addDisequality(TNode t1, TNode t2)
{
  d_eeDisequalities.push_back(t1.eqNode(t2));
}

EqcInfo* SolverState::getOrMakeEqcInfo(Node eqc, bool doMake)
{
  std::map<Node, EqcInfo*>::iterator eqc_i = d_eqcInfo.find(eqc);
  if (eqc_i != d_eqcInfo.end())
  {
    return eqc_i->second;
  }
  if (doMake)
  {
    EqcInfo* ei = new EqcInfo(d_env.getContext());
    d_eqcInfo[eqc] = ei;
    return ei;
  }
  return nullptr;
}

TheoryModel* SolverState::getModel() { return d_valuation.getModel(); }

Node SolverState::getLengthExp(Node t, std::vector<Node>& exp, Node te)
{
  Assert(areEqual(t, te));
  Node lt = utils::mkNLength(te);
  if (hasTerm(lt))
  {
    // use own length if it exists, leads to shorter explanation
    return lt;
  }
  EqcInfo* ei = getOrMakeEqcInfo(t, false);
  Node lengthTerm = ei ? ei->d_lengthTerm : Node::null();
  if (lengthTerm.isNull())
  {
    // typically shouldnt be necessary
    lengthTerm = t;
  }
  Debug("strings") << "SolverState::getLengthTerm " << t << " is " << lengthTerm
                   << std::endl;
  if (te != lengthTerm)
  {
    exp.push_back(te.eqNode(lengthTerm));
  }
  return Rewriter::rewrite(
      NodeManager::currentNM()->mkNode(STRING_LENGTH, lengthTerm));
}

Node SolverState::getLength(Node t, std::vector<Node>& exp)
{
  return getLengthExp(t, exp, t);
}

Node SolverState::explainNonEmpty(Node s)
{
  Assert(s.getType().isStringLike());
  Node emp = Word::mkEmptyWord(s.getType());
  if (areDisequal(s, emp))
  {
    return s.eqNode(emp).negate();
  }
  Node sLen = utils::mkNLength(s);
  if (areDisequal(sLen, d_zero))
  {
    return sLen.eqNode(d_zero).negate();
  }
  return Node::null();
}

bool SolverState::isEqualEmptyWord(Node s, Node& emps)
{
  Node sr = getRepresentative(s);
  if (sr.isConst())
  {
    if (Word::getLength(sr) == 0)
    {
      emps = sr;
      return true;
    }
  }
  return false;
}

void SolverState::setPendingPrefixConflictWhen(Node conf)
{
  if (conf.isNull() || d_pendingConflictSet.get())
  {
    return;
  }
  InferInfo iiPrefixConf(InferenceId::STRINGS_PREFIX_CONFLICT);
  iiPrefixConf.d_conc = d_false;
  utils::flattenOp(AND, conf, iiPrefixConf.d_premises);
  setPendingConflict(iiPrefixConf);
}

void SolverState::setPendingConflict(InferInfo& ii)
{
  if (!d_pendingConflictSet.get())
  {
    d_pendingConflict = ii;
    d_pendingConflictSet.set(true);
  }
}

bool SolverState::hasPendingConflict() const { return d_pendingConflictSet; }

bool SolverState::getPendingConflict(InferInfo& ii) const
{
  if (d_pendingConflictSet)
  {
    ii = d_pendingConflict;
    return true;
  }
  return false;
}

std::pair<bool, Node> SolverState::entailmentCheck(options::TheoryOfMode mode,
                                                   TNode lit)
{
  return d_valuation.entailmentCheck(mode, lit);
}

void SolverState::separateByLength(
    const std::vector<Node>& n,
    std::map<TypeNode, std::vector<std::vector<Node>>>& cols,
    std::map<TypeNode, std::vector<Node>>& lts)
{
  unsigned leqc_counter = 0;
  // map (length, type) to an equivalence class identifier
  std::map<std::pair<Node, TypeNode>, unsigned> eqc_to_leqc;
  // backwards map
  std::map<unsigned, std::pair<Node, TypeNode>> leqc_to_eqc;
  // Collection of eqc for each identifier. Notice that some identifiers may
  // not have an associated length in the mappings above, if the length of
  // an equivalence class is unknown.
  std::map<unsigned, std::vector<Node> > eqc_to_strings;
  NodeManager* nm = NodeManager::currentNM();
  for (const Node& eqc : n)
  {
    Assert(d_ee->getRepresentative(eqc) == eqc);
    TypeNode tnEqc = eqc.getType();
    EqcInfo* ei = getOrMakeEqcInfo(eqc, false);
    Node lt = ei ? ei->d_lengthTerm : Node::null();
    if (!lt.isNull())
    {
      lt = nm->mkNode(STRING_LENGTH, lt);
      Node r = d_ee->getRepresentative(lt);
      std::pair<Node, TypeNode> lkey(r, tnEqc);
      if (eqc_to_leqc.find(lkey) == eqc_to_leqc.end())
      {
        eqc_to_leqc[lkey] = leqc_counter;
        leqc_to_eqc[leqc_counter] = lkey;
        leqc_counter++;
      }
      eqc_to_strings[eqc_to_leqc[lkey]].push_back(eqc);
    }
    else
    {
      eqc_to_strings[leqc_counter].push_back(eqc);
      leqc_counter++;
    }
  }
  for (const std::pair<const unsigned, std::vector<Node> >& p : eqc_to_strings)
  {
    Assert(!p.second.empty());
    // get the type of the collection
    TypeNode stn = p.second[0].getType();
    cols[stn].emplace_back(p.second.begin(), p.second.end());
    lts[stn].push_back(leqc_to_eqc[p.first].first);
  }
}

}  // namespace strings
}  // namespace theory
}  // namespace cvc5


Generated by: GCOVR (Version 3.2)

Line	Exec	Source
1		/******************************************************************************
2		* Top contributors (to current version):
3		* Andrew Reynolds, Tianyi Liang, Mathias Preiner
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		* Implementation of the solver state of the theory of strings.
14		*/
15
16		#include "theory/strings/solver_state.h"
17
18		#include "theory/rewriter.h"
19		#include "theory/strings/theory_strings_utils.h"
20		#include "theory/strings/word.h"
21		#include "util/rational.h"
22
23		using namespace std;
24		using namespace cvc5::context;
25		using namespace cvc5::kind;
26
27		namespace cvc5 {
28		namespace theory {
29		namespace strings {
30
31	9926	SolverState::SolverState(Env& env, Valuation& v)
32		: TheoryState(env, v),
33		d_eeDisequalities(env.getContext()),
34		d_pendingConflictSet(env.getContext(), false),
35	9926	d_pendingConflict(InferenceId::UNKNOWN)
36		{
37	9926	d_zero = NodeManager::currentNM()->mkConst(Rational(0));
38	9926	d_false = NodeManager::currentNM()->mkConst(false);
39	9926	}
40
41	19846	SolverState::~SolverState()
42		{
43	40047	for (std::pair<const Node, EqcInfo*>& it : d_eqcInfo)
44		{
45	30124	delete it.second;
46		}
47	9923	}
48
49	11645	const context::CDList<Node>& SolverState::getDisequalityList() const
50		{
51	11645	return d_eeDisequalities;
52		}
53
54	83189	void SolverState::addDisequality(TNode t1, TNode t2)
55		{
56	83189	d_eeDisequalities.push_back(t1.eqNode(t2));
57	83189	}
58
59	2058986	EqcInfo* SolverState::getOrMakeEqcInfo(Node eqc, bool doMake)
60		{
61	2058986	std::map<Node, EqcInfo*>::iterator eqc_i = d_eqcInfo.find(eqc);
62	2058986	if (eqc_i != d_eqcInfo.end())
63		{
64	979754	return eqc_i->second;
65		}
66	1079232	if (doMake)
67		{
68	30124	EqcInfo* ei = new EqcInfo(d_env.getContext());
69	30124	d_eqcInfo[eqc] = ei;
70	30124	return ei;
71		}
72	1049108	return nullptr;
73		}
74
75		TheoryModel* SolverState::getModel() { return d_valuation.getModel(); }
76
77	1140687	Node SolverState::getLengthExp(Node t, std::vector<Node>& exp, Node te)
78		{
79	1140687	Assert(areEqual(t, te));
80	2281374	Node lt = utils::mkNLength(te);
81	1140687	if (hasTerm(lt))
82		{
83		// use own length if it exists, leads to shorter explanation
84	1138243	return lt;
85		}
86	2444	EqcInfo* ei = getOrMakeEqcInfo(t, false);
87	4888	Node lengthTerm = ei ? ei->d_lengthTerm : Node::null();
88	2444	if (lengthTerm.isNull())
89		{
90		// typically shouldnt be necessary
91	2402	lengthTerm = t;
92		}
93	4888	Debug("strings") << "SolverState::getLengthTerm " << t << " is " << lengthTerm
94	2444	<< std::endl;
95	2444	if (te != lengthTerm)
96		{
97	42	exp.push_back(te.eqNode(lengthTerm));
98		}
99		return Rewriter::rewrite(
100	2444	NodeManager::currentNM()->mkNode(STRING_LENGTH, lengthTerm));
101		}
102
103	1140683	Node SolverState::getLength(Node t, std::vector<Node>& exp)
104		{
105	1140683	return getLengthExp(t, exp, t);
106		}
107
108	17276	Node SolverState::explainNonEmpty(Node s)
109		{
110	17276	Assert(s.getType().isStringLike());
111	34552	Node emp = Word::mkEmptyWord(s.getType());
112	17276	if (areDisequal(s, emp))
113		{
114	7416	return s.eqNode(emp).negate();
115		}
116	19720	Node sLen = utils::mkNLength(s);
117	9860	if (areDisequal(sLen, d_zero))
118		{
119	9844	return sLen.eqNode(d_zero).negate();
120		}
121	16	return Node::null();
122		}
123
124	949162	bool SolverState::isEqualEmptyWord(Node s, Node& emps)
125		{
126	1898324	Node sr = getRepresentative(s);
127	949162	if (sr.isConst())
128		{
129	249049	if (Word::getLength(sr) == 0)
130		{
131	35045	emps = sr;
132	35045	return true;
133		}
134		}
135	914117	return false;
136		}
137
138	97170	void SolverState::setPendingPrefixConflictWhen(Node conf)
139		{
140	97170	if (conf.isNull() \|\| d_pendingConflictSet.get())
141		{
142	96634	return;
143		}
144	1072	InferInfo iiPrefixConf(InferenceId::STRINGS_PREFIX_CONFLICT);
145	536	iiPrefixConf.d_conc = d_false;
146	536	utils::flattenOp(AND, conf, iiPrefixConf.d_premises);
147	536	setPendingConflict(iiPrefixConf);
148		}
149
150	536	void SolverState::setPendingConflict(InferInfo& ii)
151		{
152	536	if (!d_pendingConflictSet.get())
153		{
154	536	d_pendingConflict = ii;
155	536	d_pendingConflictSet.set(true);
156		}
157	536	}
158
159	1070009	bool SolverState::hasPendingConflict() const { return d_pendingConflictSet; }
160
161	443	bool SolverState::getPendingConflict(InferInfo& ii) const
162		{
163	443	if (d_pendingConflictSet)
164		{
165	443	ii = d_pendingConflict;
166	443	return true;
167		}
168		return false;
169		}
170
171	8475	std::pair<bool, Node> SolverState::entailmentCheck(options::TheoryOfMode mode,
172		TNode lit)
173		{
174	8475	return d_valuation.entailmentCheck(mode, lit);
175		}
176
177	20223	void SolverState::separateByLength(
178		const std::vector<Node>& n,
179		std::map<TypeNode, std::vector<std::vector<Node>>>& cols,
180		std::map<TypeNode, std::vector<Node>>& lts)
181		{
182	20223	unsigned leqc_counter = 0;
183		// map (length, type) to an equivalence class identifier
184	40446	std::map<std::pair<Node, TypeNode>, unsigned> eqc_to_leqc;
185		// backwards map
186	40446	std::map<unsigned, std::pair<Node, TypeNode>> leqc_to_eqc;
187		// Collection of eqc for each identifier. Notice that some identifiers may
188		// not have an associated length in the mappings above, if the length of
189		// an equivalence class is unknown.
190	40446	std::map<unsigned, std::vector<Node> > eqc_to_strings;
191	20223	NodeManager* nm = NodeManager::currentNM();
192	95241	for (const Node& eqc : n)
193		{
194	75018	Assert(d_ee->getRepresentative(eqc) == eqc);
195	150036	TypeNode tnEqc = eqc.getType();
196	75018	EqcInfo* ei = getOrMakeEqcInfo(eqc, false);
197	150036	Node lt = ei ? ei->d_lengthTerm : Node::null();
198	75018	if (!lt.isNull())
199		{
200	75018	lt = nm->mkNode(STRING_LENGTH, lt);
201	150036	Node r = d_ee->getRepresentative(lt);
202	150036	std::pair<Node, TypeNode> lkey(r, tnEqc);
203	75018	if (eqc_to_leqc.find(lkey) == eqc_to_leqc.end())
204		{
205	47145	eqc_to_leqc[lkey] = leqc_counter;
206	47145	leqc_to_eqc[leqc_counter] = lkey;
207	47145	leqc_counter++;
208		}
209	75018	eqc_to_strings[eqc_to_leqc[lkey]].push_back(eqc);
210		}
211		else
212		{
213		eqc_to_strings[leqc_counter].push_back(eqc);
214		leqc_counter++;
215		}
216		}
217	67368	for (const std::pair<const unsigned, std::vector<Node> >& p : eqc_to_strings)
218		{
219	47145	Assert(!p.second.empty());
220		// get the type of the collection
221	94290	TypeNode stn = p.second[0].getType();
222	47145	cols[stn].emplace_back(p.second.begin(), p.second.end());
223	47145	lts[stn].push_back(leqc_to_eqc[p.first].first);
224		}
225	20223	}
226
227		} // namespace strings
228		} // namespace theory
229	29502	} // namespace cvc5