Head

GCC Code Coverage Report

Directory:	.		Exec	Total	Coverage
File:	src/theory/arith/theory_arith.cpp	Lines:	163	181	90.1 %
Date:	2021-11-05	Branches:	208	500	41.6 %


/******************************************************************************
 * 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(
          statisticsRegistry().registerTimer("theory::arith::ppRewriteTimer")),
      d_astate(env, valuation),
      d_im(env, *this, d_astate),
      d_ppre(d_env),
      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_env),
      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)
    {
      // If we computed lemmas in the last FULL_EFFORT check, send them now.
      if (d_im.hasPendingLemma())
      {
        d_im.doPendingFacts();
        d_im.doPendingLemmas();
        d_im.doPendingPhaseRequirements();
        return;
      }
      d_nonlinearExtension->finalizeModel(getValuation().getModel());
    }
    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();
    std::set<Node> termSet;
    if (d_nonlinearExtension != nullptr)
    {
      updateModelCache(termSet);
      d_nonlinearExtension->checkFullEffort(d_arithModelCache, termSet);
    }
    else if (d_internal->foundNonlinear())
    {
      // set incomplete
      d_im.setIncomplete(IncompleteId::ARITH_NL_DISABLED);
    }
    // If we won't be doing a last call effort check (which implies that
    // models will be computed), we must sanity check the integer model
    // from the linear solver now. We also must update the model cache
    // if we did not do so above.
    if (d_nonlinearExtension == nullptr)
    {
      updateModelCache(termSet);
    }
    sanityCheckIntegerModel();
  }
}

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->hasNlTerms();
  }
  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);

  // 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();
}

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())
      {
        warning() << "TheoryArithPrivate generated a bad model value for "
                     "integer variable "
                  << p.first << " : " << p.second << std::endl;
        // 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	15271	TheoryArith::TheoryArith(Env& env, OutputChannel& out, Valuation valuation)
39		: Theory(THEORY_ARITH, env, out, valuation),
40		d_ppRewriteTimer(
41	30542	statisticsRegistry().registerTimer("theory::arith::ppRewriteTimer")),
42		d_astate(env, valuation),
43		d_im(env, *this, d_astate),
44		d_ppre(d_env),
45		d_bab(env, d_astate, d_im, d_ppre, d_pnm),
46		d_eqSolver(nullptr),
47	15271	d_internal(new TheoryArithPrivate(*this, env, d_bab)),
48		d_nonlinearExtension(nullptr),
49		d_opElim(d_env),
50		d_arithPreproc(env, d_astate, d_im, d_pnm, d_opElim),
51	61084	d_rewriter(d_opElim)
52		{
53		// currently a cyclic dependency to TheoryArithPrivate
54	15271	d_astate.setParent(d_internal);
55		// indicate we are using the theory state object and inference manager
56	15271	d_theoryState = &d_astate;
57	15271	d_inferManager = &d_im;
58
59	15271	if (options().arith.arithEqSolver)
60		{
61	41	d_eqSolver.reset(new EqualitySolver(env, d_astate, d_im));
62		}
63	15271	}
64
65	45798	TheoryArith::~TheoryArith(){
66	15266	delete d_internal;
67	30532	}
68
69	15271	TheoryRewriter* TheoryArith::getTheoryRewriter() { return &d_rewriter; }
70
71	7987	ProofRuleChecker* TheoryArith::getProofChecker()
72		{
73	7987	return d_internal->getProofChecker();
74		}
75
76	15271	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	15271	if (d_eqSolver != nullptr)
81		{
82	41	return d_eqSolver->needsEqualityEngine(esi);
83		}
84		// otherwise, the linear arithmetic solver is responsible for setting up
85		// the equality engine
86	15230	return d_internal->needsEqualityEngine(esi);
87		}
88	15271	void TheoryArith::finishInit()
89		{
90	15271	const LogicInfo& logic = logicInfo();
91	15271	if (logic.isTheoryEnabled(THEORY_ARITH) && logic.areTranscendentalsUsed())
92		{
93		// witness is used to eliminate square root
94	8550	d_valuation.setUnevaluatedKind(kind::WITNESS);
95		// we only need to add the operators that are not syntax sugar
96	8550	d_valuation.setUnevaluatedKind(kind::EXPONENTIAL);
97	8550	d_valuation.setUnevaluatedKind(kind::SINE);
98	8550	d_valuation.setUnevaluatedKind(kind::PI);
99		}
100		// only need to create nonlinear extension if non-linear logic
101	15271	if (logic.isTheoryEnabled(THEORY_ARITH) && !logic.isLinear())
102		{
103	19400	d_nonlinearExtension.reset(
104	9700	new nl::NonlinearExtension(d_env, *this, d_astate));
105		}
106	15271	if (d_eqSolver != nullptr)
107		{
108	41	d_eqSolver->finishInit();
109		}
110		// finish initialize in the old linear solver
111	15271	d_internal->finishInit();
112	15271	}
113
114	903422	void TheoryArith::preRegisterTerm(TNode n)
115		{
116	903422	if (d_nonlinearExtension != nullptr)
117		{
118	440640	d_nonlinearExtension->preRegisterTerm(n);
119		}
120	903423	d_internal->preRegisterTerm(n);
121	903421	}
122
123	920199	void TheoryArith::notifySharedTerm(TNode n) { d_internal->notifySharedTerm(n); }
124
125	854272	TrustNode TheoryArith::ppRewrite(TNode atom, std::vector<SkolemLemma>& lems)
126		{
127	1708544	CodeTimer timer(d_ppRewriteTimer, /* allow_reentrant = */ true);
128	854272	Debug("arith::preprocess") << "arith::preprocess() : " << atom << endl;
129
130	854272	if (atom.getKind() == kind::EQUAL)
131		{
132	28857	return d_ppre.ppRewriteEq(atom);
133		}
134	825415	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	825421	return d_arithPreproc.eliminate(atom, lems, false);
142		}
143
144	14973	Theory::PPAssertStatus TheoryArith::ppAssert(
145		TrustNode tin, TrustSubstitutionMap& outSubstitutions)
146		{
147	14973	return d_internal->ppAssert(tin, outSubstitutions);
148		}
149
150	250915	void TheoryArith::ppStaticLearn(TNode n, NodeBuilder& learned)
151		{
152	250915	d_internal->ppStaticLearn(n, learned);
153	250915	}
154
155	2497352	bool TheoryArith::preCheck(Effort level)
156		{
157	2497352	Trace("arith-check") << "TheoryArith::preCheck " << level << std::endl;
158	2497352	return d_internal->preCheck(level);
159		}
160
161	2497352	void TheoryArith::postCheck(Effort level)
162		{
163	2497352	d_im.reset();
164	2497352	Trace("arith-check") << "TheoryArith::postCheck " << level << std::endl;
165		// check with the non-linear solver at last call
166	2497352	if (level == Theory::EFFORT_LAST_CALL)
167		{
168	3498	if (d_nonlinearExtension != nullptr)
169		{
170		// If we computed lemmas in the last FULL_EFFORT check, send them now.
171	3498	if (d_im.hasPendingLemma())
172		{
173	3161	d_im.doPendingFacts();
174	3161	d_im.doPendingLemmas();
175	3161	d_im.doPendingPhaseRequirements();
176	3161	return;
177		}
178	337	d_nonlinearExtension->finalizeModel(getValuation().getModel());
179		}
180	337	return;
181		}
182		// otherwise, check with the linear solver
183	2493854	if (d_internal->postCheck(level))
184		{
185		// linear solver emitted a conflict or lemma, return
186	67419	return;
187		}
188	2426435	if (d_im.hasSent())
189		{
190		return;
191		}
192
193	2426435	if (Theory::fullEffort(level))
194		{
195	74220	d_arithModelCache.clear();
196	148440	std::set<Node> termSet;
197	74220	if (d_nonlinearExtension != nullptr)
198		{
199	41496	updateModelCache(termSet);
200	41496	d_nonlinearExtension->checkFullEffort(d_arithModelCache, termSet);
201		}
202	32724	else if (d_internal->foundNonlinear())
203		{
204		// set incomplete
205		d_im.setIncomplete(IncompleteId::ARITH_NL_DISABLED);
206		}
207		// If we won't be doing a last call effort check (which implies that
208		// models will be computed), we must sanity check the integer model
209		// from the linear solver now. We also must update the model cache
210		// if we did not do so above.
211	74220	if (d_nonlinearExtension == nullptr)
212		{
213	32724	updateModelCache(termSet);
214		}
215	74220	sanityCheckIntegerModel();
216		}
217		}
218
219	7403893	bool TheoryArith::preNotifyFact(
220		TNode atom, bool pol, TNode fact, bool isPrereg, bool isInternal)
221		{
222	14807786	Trace("arith-check") << "TheoryArith::preNotifyFact: " << fact
223	7403893	<< ", isPrereg=" << isPrereg
224	7403893	<< ", isInternal=" << isInternal << std::endl;
225		// We do not assert to the equality engine of arithmetic in the standard way,
226		// hence we return "true" to indicate we are finished with this fact.
227	7403893	bool ret = true;
228	7403893	if (d_eqSolver != nullptr)
229		{
230		// the equality solver may indicate ret = false, after which the assertion
231		// will be asserted to the equality engine in the default way.
232	2425	ret = d_eqSolver->preNotifyFact(atom, pol, fact, isPrereg, isInternal);
233		}
234		// we also always also notify the internal solver
235	7403893	d_internal->preNotifyFact(atom, pol, fact);
236	7403893	return ret;
237		}
238
239	27334	bool TheoryArith::needsCheckLastEffort() {
240	27334	if (d_nonlinearExtension != nullptr)
241		{
242	14023	return d_nonlinearExtension->hasNlTerms();
243		}
244	13311	return false;
245		}
246
247	28101	TrustNode TheoryArith::explain(TNode n)
248		{
249	28101	if (d_eqSolver != nullptr)
250		{
251		// if the equality solver has an explanation for it, use it
252	54	TrustNode texp = d_eqSolver->explain(n);
253	27	if (!texp.isNull())
254		{
255		return texp;
256		}
257		}
258	28101	return d_internal->explain(n);
259		}
260
261	3870181	void TheoryArith::propagate(Effort e) {
262	3870181	d_internal->propagate(e);
263	3870181	}
264
265	22882	bool TheoryArith::collectModelInfo(TheoryModel* m,
266		const std::set<Node>& termSet)
267		{
268		// this overrides behavior to not assert equality engine
269	22882	return collectModelValues(m, termSet);
270		}
271
272	22882	bool TheoryArith::collectModelValues(TheoryModel* m,
273		const std::set<Node>& termSet)
274		{
275	22882	if (Trace.isOn("arith::model"))
276		{
277		Trace("arith::model") << "arithmetic model after pruning" << std::endl;
278		for (const auto& p : d_arithModelCache)
279		{
280		Trace("arith::model") << "\t" << p.first << " -> " << p.second << std::endl;
281		}
282		}
283
284	22882	updateModelCache(termSet);
285
286		// We are now ready to assert the model.
287	463738	for (const std::pair<const Node, Node>& p : d_arithModelCache)
288		{
289	440856	if (termSet.find(p.first) == termSet.end())
290		{
291	4	continue;
292		}
293		// maps to constant of comparable type
294	440852	Assert(p.first.getType().isComparableTo(p.second.getType()));
295	440852	if (m->assertEquality(p.first, p.second, true))
296		{
297	440852	continue;
298		}
299		Assert(false) << "A model equality could not be asserted: " << p.first
300		<< " == " << p.second << std::endl;
301		// If we failed to assert an equality, it is likely due to theory
302		// combination, namely the repaired model for non-linear changed
303		// an equality status that was agreed upon by both (linear) arithmetic
304		// and another theory. In this case, we must add a lemma, or otherwise
305		// we would terminate with an invalid model. Thus, we add a splitting
306		// lemma of the form ( x = v V x != v ) where v is the model value
307		// assigned by the non-linear solver to x.
308		if (d_nonlinearExtension != nullptr)
309		{
310		Node eq = p.first.eqNode(p.second);
311		Node lem = NodeManager::currentNM()->mkNode(kind::OR, eq, eq.negate());
312		bool added = d_im.lemma(lem, InferenceId::ARITH_SPLIT_FOR_NL_MODEL);
313		AlwaysAssert(added) << "The lemma was already in cache. Probably there is something wrong with theory combination...";
314		}
315		return false;
316		}
317	22882	return true;
318		}
319
320	1957	void TheoryArith::notifyRestart(){
321	1957	d_internal->notifyRestart();
322	1957	}
323
324	20558	void TheoryArith::presolve(){
325	20558	d_internal->presolve();
326	20558	}
327
328	816122	EqualityStatus TheoryArith::getEqualityStatus(TNode a, TNode b) {
329	816122	Debug("arith") << "TheoryArith::getEqualityStatus(" << a << ", " << b << ")" << std::endl;
330	816122	if (d_arithModelCache.empty())
331		{
332		return d_internal->getEqualityStatus(a,b);
333		}
334	1632244	Node aval = Rewriter::rewrite(a.substitute(d_arithModelCache.begin(), d_arithModelCache.end()));
335	1632244	Node bval = Rewriter::rewrite(b.substitute(d_arithModelCache.begin(), d_arithModelCache.end()));
336	816122	if (aval == bval)
337		{
338	76895	return EQUALITY_TRUE_IN_MODEL;
339		}
340	739227	return EQUALITY_FALSE_IN_MODEL;
341		}
342
343	2957	Node TheoryArith::getModelValue(TNode var) {
344	2957	return d_internal->getModelValue( var );
345		}
346
347	8478	std::pair<bool, Node> TheoryArith::entailmentCheck(TNode lit)
348		{
349	16956	ArithEntailmentCheckParameters def;
350	8478	def.addLookupRowSumAlgorithms();
351	16956	ArithEntailmentCheckSideEffects ase;
352	8478	std::pair<bool, Node> res = d_internal->entailmentCheck(lit, def, ase);
353	16956	return res;
354		}
355		eq::ProofEqEngine* TheoryArith::getProofEqEngine()
356		{
357		return d_im.getProofEqEngine();
358		}
359
360	74220	void TheoryArith::updateModelCache(std::set<Node>& termSet)
361		{
362	74220	if (d_arithModelCache.empty())
363		{
364	74220	collectAssertedTerms(termSet);
365	74220	d_internal->collectModelValues(termSet, d_arithModelCache);
366		}
367	74220	}
368	22882	void TheoryArith::updateModelCache(const std::set<Node>& termSet)
369		{
370	22882	if (d_arithModelCache.empty())
371		{
372	5707	d_internal->collectModelValues(termSet, d_arithModelCache);
373		}
374	22882	}
375	74220	bool TheoryArith::sanityCheckIntegerModel()
376		{
377
378		// Double check that the model from the linear solver respects integer types,
379		// if it does not, add a branch and bound lemma. This typically should never
380		// be necessary, but is needed in rare cases.
381	74220	bool addedLemma = false;
382	74220	bool badAssignment = false;
383	74220	Trace("arith-check") << "model:" << std::endl;
384	2270461	for (const auto& p : d_arithModelCache)
385		{
386	2196241	Trace("arith-check") << p.first << " -> " << p.second << std::endl;
387	2196241	if (p.first.getType().isInteger() && !p.second.getType().isInteger())
388		{
389	4	warning() << "TheoryArithPrivate generated a bad model value for "
390	4	"integer variable "
391	4	<< p.first << " : " << p.second << std::endl;
392		// must branch and bound
393		TrustNode lem =
394	8	d_bab.branchIntegerVariable(p.first, p.second.getConst<Rational>());
395	4	if (d_im.trustedLemma(lem, InferenceId::ARITH_BB_LEMMA))
396		{
397	4	addedLemma = true;
398		}
399	4	badAssignment = true;
400		}
401		}
402	74220	if (addedLemma)
403		{
404		// we had to add a branch and bound lemma since the linear solver assigned
405		// a non-integer value to an integer variable.
406	4	return true;
407		}
408		// this would imply that linear arithmetic's model failed to satisfy a branch
409		// and bound lemma
410	74216	AlwaysAssert(!badAssignment)
411		<< "Bad assignment from TheoryArithPrivate::collectModelValues, and no "
412		"branching lemma was sent";
413	74216	return false;
414		}
415
416		} // namespace arith
417		} // namespace theory
418	31125	} // namespace cvc5