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GCC Code Coverage Report

Directory:	.		Exec	Total	Coverage
File:	src/theory/arith/theory_arith.cpp	Lines:	153	179	85.5 %
Date:	2021-09-10	Branches:	194	516	37.6 %


/******************************************************************************
 * Top contributors (to current version):
 *   Andrew Reynolds, Tim King, Alex Ozdemir
 *
 * 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.
 * ****************************************************************************
 *
 * Arithmetic theory.
 */

#include "theory/arith/theory_arith.h"

#include "options/smt_options.h"
#include "proof/proof_checker.h"
#include "proof/proof_rule.h"
#include "smt/smt_statistics_registry.h"
#include "theory/arith/arith_rewriter.h"
#include "theory/arith/equality_solver.h"
#include "theory/arith/infer_bounds.h"
#include "theory/arith/nl/nonlinear_extension.h"
#include "theory/arith/theory_arith_private.h"
#include "theory/ext_theory.h"
#include "theory/rewriter.h"
#include "theory/theory_model.h"

using namespace std;
using namespace cvc5::kind;

namespace cvc5 {
namespace theory {
namespace arith {

TheoryArith::TheoryArith(Env& env, OutputChannel& out, Valuation valuation)
    : Theory(THEORY_ARITH, env, out, valuation),
      d_ppRewriteTimer(smtStatisticsRegistry().registerTimer(
          "theory::arith::ppRewriteTimer")),
      d_astate(env, valuation),
      d_im(env, *this, d_astate, d_pnm),
      d_ppre(context(), d_pnm),
      d_bab(env, d_astate, d_im, d_ppre, d_pnm),
      d_eqSolver(nullptr),
      d_internal(new TheoryArithPrivate(*this, env, d_bab)),
      d_nonlinearExtension(nullptr),
      d_opElim(d_pnm, logicInfo()),
      d_arithPreproc(env, d_astate, d_im, d_pnm, d_opElim),
      d_rewriter(d_opElim)
{
  // currently a cyclic dependency to TheoryArithPrivate
  d_astate.setParent(d_internal);
  // indicate we are using the theory state object and inference manager
  d_theoryState = &d_astate;
  d_inferManager = &d_im;

  if (options().arith.arithEqSolver)
  {
    d_eqSolver.reset(new EqualitySolver(env, d_astate, d_im));
  }
}

TheoryArith::~TheoryArith(){
  delete d_internal;
}

TheoryRewriter* TheoryArith::getTheoryRewriter() { return &d_rewriter; }

ProofRuleChecker* TheoryArith::getProofChecker()
{
  return d_internal->getProofChecker();
}

bool TheoryArith::needsEqualityEngine(EeSetupInfo& esi)
{
  // if the equality solver is enabled, then it is responsible for setting
  // up the equality engine
  if (d_eqSolver != nullptr)
  {
    return d_eqSolver->needsEqualityEngine(esi);
  }
  // otherwise, the linear arithmetic solver is responsible for setting up
  // the equality engine
  return d_internal->needsEqualityEngine(esi);
}
void TheoryArith::finishInit()
{
  const LogicInfo& logic = logicInfo();
  if (logic.isTheoryEnabled(THEORY_ARITH) && logic.areTranscendentalsUsed())
  {
    // witness is used to eliminate square root
    d_valuation.setUnevaluatedKind(kind::WITNESS);
    // we only need to add the operators that are not syntax sugar
    d_valuation.setUnevaluatedKind(kind::EXPONENTIAL);
    d_valuation.setUnevaluatedKind(kind::SINE);
    d_valuation.setUnevaluatedKind(kind::PI);
  }
  // only need to create nonlinear extension if non-linear logic
  if (logic.isTheoryEnabled(THEORY_ARITH) && !logic.isLinear())
  {
    d_nonlinearExtension.reset(
        new nl::NonlinearExtension(d_env, *this, d_astate));
  }
  if (d_eqSolver != nullptr)
  {
    d_eqSolver->finishInit();
  }
  // finish initialize in the old linear solver
  d_internal->finishInit();
}

void TheoryArith::preRegisterTerm(TNode n)
{
  if (d_nonlinearExtension != nullptr)
  {
    d_nonlinearExtension->preRegisterTerm(n);
  }
  d_internal->preRegisterTerm(n);
}

void TheoryArith::notifySharedTerm(TNode n) { d_internal->notifySharedTerm(n); }

TrustNode TheoryArith::ppRewrite(TNode atom, std::vector<SkolemLemma>& lems)
{
  CodeTimer timer(d_ppRewriteTimer, /* allow_reentrant = */ true);
  Debug("arith::preprocess") << "arith::preprocess() : " << atom << endl;

  if (atom.getKind() == kind::EQUAL)
  {
    return d_ppre.ppRewriteEq(atom);
  }
  Assert(Theory::theoryOf(atom) == THEORY_ARITH);
  // Eliminate operators. Notice we must do this here since other
  // theories may generate lemmas that involve non-standard operators. For
  // example, quantifier instantiation may use TO_INTEGER terms; SyGuS may
  // introduce non-standard arithmetic terms appearing in grammars.
  // call eliminate operators. In contrast to expandDefinitions, we eliminate
  // *all* extended arithmetic operators here, including total ones.
  return d_arithPreproc.eliminate(atom, lems, false);
}

Theory::PPAssertStatus TheoryArith::ppAssert(
    TrustNode tin, TrustSubstitutionMap& outSubstitutions)
{
  return d_internal->ppAssert(tin, outSubstitutions);
}

void TheoryArith::ppStaticLearn(TNode n, NodeBuilder& learned)
{
  d_internal->ppStaticLearn(n, learned);
}

bool TheoryArith::preCheck(Effort level)
{
  Trace("arith-check") << "TheoryArith::preCheck " << level << std::endl;
  return d_internal->preCheck(level);
}

void TheoryArith::postCheck(Effort level)
{
  d_im.reset();
  Trace("arith-check") << "TheoryArith::postCheck " << level << std::endl;
  // check with the non-linear solver at last call
  if (level == Theory::EFFORT_LAST_CALL)
  {
    if (d_nonlinearExtension != nullptr)
    {
      d_nonlinearExtension->check(level);
    }
    return;
  }
  // otherwise, check with the linear solver
  if (d_internal->postCheck(level))
  {
    // linear solver emitted a conflict or lemma, return
    return;
  }
  if (d_im.hasSent())
  {
    return;
  }

  if (Theory::fullEffort(level))
  {
    d_arithModelCache.clear();
    if (d_nonlinearExtension != nullptr)
    {
      std::set<Node> termSet;
      updateModelCache(termSet);
      d_nonlinearExtension->check(level);
      d_nonlinearExtension->interceptModel(d_arithModelCache, termSet);
    }
    else if (d_internal->foundNonlinear())
    {
      // set incomplete
      d_im.setIncomplete(IncompleteId::ARITH_NL_DISABLED);
    }
  }
}

bool TheoryArith::preNotifyFact(
    TNode atom, bool pol, TNode fact, bool isPrereg, bool isInternal)
{
  Trace("arith-check") << "TheoryArith::preNotifyFact: " << fact
                       << ", isPrereg=" << isPrereg
                       << ", isInternal=" << isInternal << std::endl;
  // We do not assert to the equality engine of arithmetic in the standard way,
  // hence we return "true" to indicate we are finished with this fact.
  bool ret = true;
  if (d_eqSolver != nullptr)
  {
    // the equality solver may indicate ret = false, after which the assertion
    // will be asserted to the equality engine in the default way.
    ret = d_eqSolver->preNotifyFact(atom, pol, fact, isPrereg, isInternal);
  }
  // we also always also notify the internal solver
  d_internal->preNotifyFact(atom, pol, fact);
  return ret;
}

bool TheoryArith::needsCheckLastEffort() {
  if (d_nonlinearExtension != nullptr)
  {
    return d_nonlinearExtension->needsCheckLastEffort();
  }
  return false;
}

TrustNode TheoryArith::explain(TNode n)
{
  if (d_eqSolver != nullptr)
  {
    // if the equality solver has an explanation for it, use it
    TrustNode texp = d_eqSolver->explain(n);
    if (!texp.isNull())
    {
      return texp;
    }
  }
  return d_internal->explain(n);
}

void TheoryArith::propagate(Effort e) {
  d_internal->propagate(e);
}

bool TheoryArith::collectModelInfo(TheoryModel* m,
                                   const std::set<Node>& termSet)
{
  // this overrides behavior to not assert equality engine
  return collectModelValues(m, termSet);
}

bool TheoryArith::collectModelValues(TheoryModel* m,
                                     const std::set<Node>& termSet)
{
  if (Trace.isOn("arith::model"))
  {
    Trace("arith::model") << "arithmetic model after pruning" << std::endl;
    for (const auto& p : d_arithModelCache)
    {
      Trace("arith::model") << "\t" << p.first << " -> " << p.second << std::endl;
    }
  }

  updateModelCache(termSet);

  if (sanityCheckIntegerModel())
  {
    // We added a lemma
    return false;
  }

  // We are now ready to assert the model.
  for (const std::pair<const Node, Node>& p : d_arithModelCache)
  {
    if (termSet.find(p.first) == termSet.end())
    {
      continue;
    }
    // maps to constant of comparable type
    Assert(p.first.getType().isComparableTo(p.second.getType()));
    if (m->assertEquality(p.first, p.second, true))
    {
      continue;
    }
    Assert(false) << "A model equality could not be asserted: " << p.first
                        << " == " << p.second << std::endl;
    // If we failed to assert an equality, it is likely due to theory
    // combination, namely the repaired model for non-linear changed
    // an equality status that was agreed upon by both (linear) arithmetic
    // and another theory. In this case, we must add a lemma, or otherwise
    // we would terminate with an invalid model. Thus, we add a splitting
    // lemma of the form ( x = v V x != v ) where v is the model value
    // assigned by the non-linear solver to x.
    if (d_nonlinearExtension != nullptr)
    {
      Node eq = p.first.eqNode(p.second);
      Node lem = NodeManager::currentNM()->mkNode(kind::OR, eq, eq.negate());
      bool added = d_im.lemma(lem, InferenceId::ARITH_SPLIT_FOR_NL_MODEL);
      AlwaysAssert(added) << "The lemma was already in cache. Probably there is something wrong with theory combination...";
    }
    return false;
  }
  return true;
}

void TheoryArith::notifyRestart(){
  d_internal->notifyRestart();
}

void TheoryArith::presolve(){
  d_internal->presolve();
  if (d_nonlinearExtension != nullptr)
  {
    d_nonlinearExtension->presolve();
  }
}

EqualityStatus TheoryArith::getEqualityStatus(TNode a, TNode b) {
  Debug("arith") << "TheoryArith::getEqualityStatus(" << a << ", " << b << ")" << std::endl;
  if (d_arithModelCache.empty())
  {
    return d_internal->getEqualityStatus(a,b);
  }
  Node aval = Rewriter::rewrite(a.substitute(d_arithModelCache.begin(), d_arithModelCache.end()));
  Node bval = Rewriter::rewrite(b.substitute(d_arithModelCache.begin(), d_arithModelCache.end()));
  if (aval == bval)
  {
    return EQUALITY_TRUE_IN_MODEL;
  }
  return EQUALITY_FALSE_IN_MODEL;
}

Node TheoryArith::getModelValue(TNode var) {
  return d_internal->getModelValue( var );
}

std::pair<bool, Node> TheoryArith::entailmentCheck(TNode lit)
{
  ArithEntailmentCheckParameters def;
  def.addLookupRowSumAlgorithms();
  ArithEntailmentCheckSideEffects ase;
  std::pair<bool, Node> res = d_internal->entailmentCheck(lit, def, ase);
  return res;
}
eq::ProofEqEngine* TheoryArith::getProofEqEngine()
{
  return d_im.getProofEqEngine();
}

void TheoryArith::updateModelCache(std::set<Node>& termSet)
{
  if (d_arithModelCache.empty())
  {
    collectAssertedTerms(termSet);
    d_internal->collectModelValues(termSet, d_arithModelCache);
  }
}
void TheoryArith::updateModelCache(const std::set<Node>& termSet)
{
  if (d_arithModelCache.empty())
  {
    d_internal->collectModelValues(termSet, d_arithModelCache);
  }
}
bool TheoryArith::sanityCheckIntegerModel()
{

    // Double check that the model from the linear solver respects integer types,
    // if it does not, add a branch and bound lemma. This typically should never
    // be necessary, but is needed in rare cases.
    bool addedLemma = false;
    bool badAssignment = false;
    Trace("arith-check") << "model:" << std::endl;
    for (const auto& p : d_arithModelCache)
    {
      Trace("arith-check") << p.first << " -> " << p.second << std::endl;
      if (p.first.getType().isInteger() && !p.second.getType().isInteger())
      {
        Assert(false) << "TheoryArithPrivate generated a bad model value for "
                        "integer variable "
                      << p.first << " : " << p.second;
        // must branch and bound
        TrustNode lem =
            d_bab.branchIntegerVariable(p.first, p.second.getConst<Rational>());
        if (d_im.trustedLemma(lem, InferenceId::ARITH_BB_LEMMA))
        {
          addedLemma = true;
        }
        badAssignment = true;
      }
    }
    if (addedLemma)
    {
      // we had to add a branch and bound lemma since the linear solver assigned
      // a non-integer value to an integer variable.
      return true;
    }
    // this would imply that linear arithmetic's model failed to satisfy a branch
    // and bound lemma
    AlwaysAssert(!badAssignment)
        << "Bad assignment from TheoryArithPrivate::collectModelValues, and no "
          "branching lemma was sent";
    return false;
}

}  // namespace arith
}  // namespace theory
}  // namespace cvc5


Generated by: GCOVR (Version 3.2)

Line	Exec	Source
1		/******************************************************************************
2		* Top contributors (to current version):
3		* Andrew Reynolds, Tim King, Alex Ozdemir
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		* Arithmetic theory.
14		*/
15
16		#include "theory/arith/theory_arith.h"
17
18		#include "options/smt_options.h"
19		#include "proof/proof_checker.h"
20		#include "proof/proof_rule.h"
21		#include "smt/smt_statistics_registry.h"
22		#include "theory/arith/arith_rewriter.h"
23		#include "theory/arith/equality_solver.h"
24		#include "theory/arith/infer_bounds.h"
25		#include "theory/arith/nl/nonlinear_extension.h"
26		#include "theory/arith/theory_arith_private.h"
27		#include "theory/ext_theory.h"
28		#include "theory/rewriter.h"
29		#include "theory/theory_model.h"
30
31		using namespace std;
32		using namespace cvc5::kind;
33
34		namespace cvc5 {
35		namespace theory {
36		namespace arith {
37
38	9913	TheoryArith::TheoryArith(Env& env, OutputChannel& out, Valuation valuation)
39		: Theory(THEORY_ARITH, env, out, valuation),
40	9913	d_ppRewriteTimer(smtStatisticsRegistry().registerTimer(
41	19826	"theory::arith::ppRewriteTimer")),
42		d_astate(env, valuation),
43		d_im(env, *this, d_astate, d_pnm),
44		d_ppre(context(), d_pnm),
45		d_bab(env, d_astate, d_im, d_ppre, d_pnm),
46		d_eqSolver(nullptr),
47	9913	d_internal(new TheoryArithPrivate(*this, env, d_bab)),
48		d_nonlinearExtension(nullptr),
49		d_opElim(d_pnm, logicInfo()),
50		d_arithPreproc(env, d_astate, d_im, d_pnm, d_opElim),
51	39652	d_rewriter(d_opElim)
52		{
53		// currently a cyclic dependency to TheoryArithPrivate
54	9913	d_astate.setParent(d_internal);
55		// indicate we are using the theory state object and inference manager
56	9913	d_theoryState = &d_astate;
57	9913	d_inferManager = &d_im;
58
59	9913	if (options().arith.arithEqSolver)
60		{
61	39	d_eqSolver.reset(new EqualitySolver(env, d_astate, d_im));
62		}
63	9913	}
64
65	29730	TheoryArith::~TheoryArith(){
66	9910	delete d_internal;
67	19820	}
68
69	9913	TheoryRewriter* TheoryArith::getTheoryRewriter() { return &d_rewriter; }
70
71	3781	ProofRuleChecker* TheoryArith::getProofChecker()
72		{
73	3781	return d_internal->getProofChecker();
74		}
75
76	9913	bool TheoryArith::needsEqualityEngine(EeSetupInfo& esi)
77		{
78		// if the equality solver is enabled, then it is responsible for setting
79		// up the equality engine
80	9913	if (d_eqSolver != nullptr)
81		{
82	39	return d_eqSolver->needsEqualityEngine(esi);
83		}
84		// otherwise, the linear arithmetic solver is responsible for setting up
85		// the equality engine
86	9874	return d_internal->needsEqualityEngine(esi);
87		}
88	9913	void TheoryArith::finishInit()
89		{
90	9913	const LogicInfo& logic = logicInfo();
91	9913	if (logic.isTheoryEnabled(THEORY_ARITH) && logic.areTranscendentalsUsed())
92		{
93		// witness is used to eliminate square root
94	4236	d_valuation.setUnevaluatedKind(kind::WITNESS);
95		// we only need to add the operators that are not syntax sugar
96	4236	d_valuation.setUnevaluatedKind(kind::EXPONENTIAL);
97	4236	d_valuation.setUnevaluatedKind(kind::SINE);
98	4236	d_valuation.setUnevaluatedKind(kind::PI);
99		}
100		// only need to create nonlinear extension if non-linear logic
101	9913	if (logic.isTheoryEnabled(THEORY_ARITH) && !logic.isLinear())
102		{
103	10386	d_nonlinearExtension.reset(
104	5193	new nl::NonlinearExtension(d_env, *this, d_astate));
105		}
106	9913	if (d_eqSolver != nullptr)
107		{
108	39	d_eqSolver->finishInit();
109		}
110		// finish initialize in the old linear solver
111	9913	d_internal->finishInit();
112	9913	}
113
114	818203	void TheoryArith::preRegisterTerm(TNode n)
115		{
116	818203	if (d_nonlinearExtension != nullptr)
117		{
118	410361	d_nonlinearExtension->preRegisterTerm(n);
119		}
120	818204	d_internal->preRegisterTerm(n);
121	818202	}
122
123	642897	void TheoryArith::notifySharedTerm(TNode n) { d_internal->notifySharedTerm(n); }
124
125	776801	TrustNode TheoryArith::ppRewrite(TNode atom, std::vector<SkolemLemma>& lems)
126		{
127	1553602	CodeTimer timer(d_ppRewriteTimer, /* allow_reentrant = */ true);
128	776801	Debug("arith::preprocess") << "arith::preprocess() : " << atom << endl;
129
130	776801	if (atom.getKind() == kind::EQUAL)
131		{
132	27109	return d_ppre.ppRewriteEq(atom);
133		}
134	749692	Assert(Theory::theoryOf(atom) == THEORY_ARITH);
135		// Eliminate operators. Notice we must do this here since other
136		// theories may generate lemmas that involve non-standard operators. For
137		// example, quantifier instantiation may use TO_INTEGER terms; SyGuS may
138		// introduce non-standard arithmetic terms appearing in grammars.
139		// call eliminate operators. In contrast to expandDefinitions, we eliminate
140		// all extended arithmetic operators here, including total ones.
141	749698	return d_arithPreproc.eliminate(atom, lems, false);
142		}
143
144	11724	Theory::PPAssertStatus TheoryArith::ppAssert(
145		TrustNode tin, TrustSubstitutionMap& outSubstitutions)
146		{
147	11724	return d_internal->ppAssert(tin, outSubstitutions);
148		}
149
150	105422	void TheoryArith::ppStaticLearn(TNode n, NodeBuilder& learned)
151		{
152	105422	d_internal->ppStaticLearn(n, learned);
153	105422	}
154
155	1804806	bool TheoryArith::preCheck(Effort level)
156		{
157	1804806	Trace("arith-check") << "TheoryArith::preCheck " << level << std::endl;
158	1804806	return d_internal->preCheck(level);
159		}
160
161	1804806	void TheoryArith::postCheck(Effort level)
162		{
163	1804806	d_im.reset();
164	1804806	Trace("arith-check") << "TheoryArith::postCheck " << level << std::endl;
165		// check with the non-linear solver at last call
166	1804806	if (level == Theory::EFFORT_LAST_CALL)
167		{
168	3297	if (d_nonlinearExtension != nullptr)
169		{
170	3297	d_nonlinearExtension->check(level);
171		}
172	3297	return;
173		}
174		// otherwise, check with the linear solver
175	1801509	if (d_internal->postCheck(level))
176		{
177		// linear solver emitted a conflict or lemma, return
178	57994	return;
179		}
180	1743515	if (d_im.hasSent())
181		{
182		return;
183		}
184
185	1743515	if (Theory::fullEffort(level))
186		{
187	62092	d_arithModelCache.clear();
188	62092	if (d_nonlinearExtension != nullptr)
189		{
190	68864	std::set<Node> termSet;
191	34432	updateModelCache(termSet);
192	34432	d_nonlinearExtension->check(level);
193	34432	d_nonlinearExtension->interceptModel(d_arithModelCache, termSet);
194		}
195	27660	else if (d_internal->foundNonlinear())
196		{
197		// set incomplete
198		d_im.setIncomplete(IncompleteId::ARITH_NL_DISABLED);
199		}
200		}
201		}
202
203	5893188	bool TheoryArith::preNotifyFact(
204		TNode atom, bool pol, TNode fact, bool isPrereg, bool isInternal)
205		{
206	11786376	Trace("arith-check") << "TheoryArith::preNotifyFact: " << fact
207	5893188	<< ", isPrereg=" << isPrereg
208	5893188	<< ", isInternal=" << isInternal << std::endl;
209		// We do not assert to the equality engine of arithmetic in the standard way,
210		// hence we return "true" to indicate we are finished with this fact.
211	5893188	bool ret = true;
212	5893188	if (d_eqSolver != nullptr)
213		{
214		// the equality solver may indicate ret = false, after which the assertion
215		// will be asserted to the equality engine in the default way.
216	2543	ret = d_eqSolver->preNotifyFact(atom, pol, fact, isPrereg, isInternal);
217		}
218		// we also always also notify the internal solver
219	5893188	d_internal->preNotifyFact(atom, pol, fact);
220	5893188	return ret;
221		}
222
223	18680	bool TheoryArith::needsCheckLastEffort() {
224	18680	if (d_nonlinearExtension != nullptr)
225		{
226	10056	return d_nonlinearExtension->needsCheckLastEffort();
227		}
228	8624	return false;
229		}
230
231	25921	TrustNode TheoryArith::explain(TNode n)
232		{
233	25921	if (d_eqSolver != nullptr)
234		{
235		// if the equality solver has an explanation for it, use it
236	54	TrustNode texp = d_eqSolver->explain(n);
237	27	if (!texp.isNull())
238		{
239		return texp;
240		}
241		}
242	25921	return d_internal->explain(n);
243		}
244
245	2744391	void TheoryArith::propagate(Effort e) {
246	2744391	d_internal->propagate(e);
247	2744391	}
248
249	14441	bool TheoryArith::collectModelInfo(TheoryModel* m,
250		const std::set<Node>& termSet)
251		{
252		// this overrides behavior to not assert equality engine
253	14441	return collectModelValues(m, termSet);
254		}
255
256	14441	bool TheoryArith::collectModelValues(TheoryModel* m,
257		const std::set<Node>& termSet)
258		{
259	14441	if (Trace.isOn("arith::model"))
260		{
261		Trace("arith::model") << "arithmetic model after pruning" << std::endl;
262		for (const auto& p : d_arithModelCache)
263		{
264		Trace("arith::model") << "\t" << p.first << " -> " << p.second << std::endl;
265		}
266		}
267
268	14441	updateModelCache(termSet);
269
270	14441	if (sanityCheckIntegerModel())
271		{
272		// We added a lemma
273		return false;
274		}
275
276		// We are now ready to assert the model.
277	265136	for (const std::pair<const Node, Node>& p : d_arithModelCache)
278		{
279	250695	if (termSet.find(p.first) == termSet.end())
280		{
281	2	continue;
282		}
283		// maps to constant of comparable type
284	250693	Assert(p.first.getType().isComparableTo(p.second.getType()));
285	250693	if (m->assertEquality(p.first, p.second, true))
286		{
287	250693	continue;
288		}
289		Assert(false) << "A model equality could not be asserted: " << p.first
290		<< " == " << p.second << std::endl;
291		// If we failed to assert an equality, it is likely due to theory
292		// combination, namely the repaired model for non-linear changed
293		// an equality status that was agreed upon by both (linear) arithmetic
294		// and another theory. In this case, we must add a lemma, or otherwise
295		// we would terminate with an invalid model. Thus, we add a splitting
296		// lemma of the form ( x = v V x != v ) where v is the model value
297		// assigned by the non-linear solver to x.
298		if (d_nonlinearExtension != nullptr)
299		{
300		Node eq = p.first.eqNode(p.second);
301		Node lem = NodeManager::currentNM()->mkNode(kind::OR, eq, eq.negate());
302		bool added = d_im.lemma(lem, InferenceId::ARITH_SPLIT_FOR_NL_MODEL);
303		AlwaysAssert(added) << "The lemma was already in cache. Probably there is something wrong with theory combination...";
304		}
305		return false;
306		}
307	14441	return true;
308		}
309
310	1689	void TheoryArith::notifyRestart(){
311	1689	d_internal->notifyRestart();
312	1689	}
313
314	15237	void TheoryArith::presolve(){
315	15237	d_internal->presolve();
316	15237	if (d_nonlinearExtension != nullptr)
317		{
318	6425	d_nonlinearExtension->presolve();
319		}
320	15237	}
321
322	780587	EqualityStatus TheoryArith::getEqualityStatus(TNode a, TNode b) {
323	780587	Debug("arith") << "TheoryArith::getEqualityStatus(" << a << ", " << b << ")" << std::endl;
324	780587	if (d_arithModelCache.empty())
325		{
326	747572	return d_internal->getEqualityStatus(a,b);
327		}
328	66030	Node aval = Rewriter::rewrite(a.substitute(d_arithModelCache.begin(), d_arithModelCache.end()));
329	66030	Node bval = Rewriter::rewrite(b.substitute(d_arithModelCache.begin(), d_arithModelCache.end()));
330	33015	if (aval == bval)
331		{
332	10752	return EQUALITY_TRUE_IN_MODEL;
333		}
334	22263	return EQUALITY_FALSE_IN_MODEL;
335		}
336
337	2961	Node TheoryArith::getModelValue(TNode var) {
338	2961	return d_internal->getModelValue( var );
339		}
340
341	8517	std::pair<bool, Node> TheoryArith::entailmentCheck(TNode lit)
342		{
343	17034	ArithEntailmentCheckParameters def;
344	8517	def.addLookupRowSumAlgorithms();
345	17034	ArithEntailmentCheckSideEffects ase;
346	8517	std::pair<bool, Node> res = d_internal->entailmentCheck(lit, def, ase);
347	17034	return res;
348		}
349		eq::ProofEqEngine* TheoryArith::getProofEqEngine()
350		{
351		return d_im.getProofEqEngine();
352		}
353
354	34432	void TheoryArith::updateModelCache(std::set<Node>& termSet)
355		{
356	34432	if (d_arithModelCache.empty())
357		{
358	34432	collectAssertedTerms(termSet);
359	34432	d_internal->collectModelValues(termSet, d_arithModelCache);
360		}
361	34432	}
362	14441	void TheoryArith::updateModelCache(const std::set<Node>& termSet)
363		{
364	14441	if (d_arithModelCache.empty())
365		{
366	8097	d_internal->collectModelValues(termSet, d_arithModelCache);
367		}
368	14441	}
369	14441	bool TheoryArith::sanityCheckIntegerModel()
370		{
371
372		// Double check that the model from the linear solver respects integer types,
373		// if it does not, add a branch and bound lemma. This typically should never
374		// be necessary, but is needed in rare cases.
375	14441	bool addedLemma = false;
376	14441	bool badAssignment = false;
377	14441	Trace("arith-check") << "model:" << std::endl;
378	265136	for (const auto& p : d_arithModelCache)
379		{
380	250695	Trace("arith-check") << p.first << " -> " << p.second << std::endl;
381	250695	if (p.first.getType().isInteger() && !p.second.getType().isInteger())
382		{
383		Assert(false) << "TheoryArithPrivate generated a bad model value for "
384		"integer variable "
385		<< p.first << " : " << p.second;
386		// must branch and bound
387		TrustNode lem =
388		d_bab.branchIntegerVariable(p.first, p.second.getConst<Rational>());
389		if (d_im.trustedLemma(lem, InferenceId::ARITH_BB_LEMMA))
390		{
391		addedLemma = true;
392		}
393		badAssignment = true;
394		}
395		}
396	14441	if (addedLemma)
397		{
398		// we had to add a branch and bound lemma since the linear solver assigned
399		// a non-integer value to an integer variable.
400		return true;
401		}
402		// this would imply that linear arithmetic's model failed to satisfy a branch
403		// and bound lemma
404	14441	AlwaysAssert(!badAssignment)
405		<< "Bad assignment from TheoryArithPrivate::collectModelValues, and no "
406		"branching lemma was sent";
407	14441	return false;
408		}
409
410		} // namespace arith
411		} // namespace theory
412	29502	} // namespace cvc5