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/********************* */
/*! \file inference_manager.cpp
** \verbatim
** Top contributors (to current version):
** Andrew Reynolds
** This file is part of the CVC4 project.
** Copyright (c) 2009-2020 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.\endverbatim
**
** \brief Implementation of the inference manager for the theory of sets
**/
#include "theory/sets/inference_manager.h"
#include "options/sets_options.h"
using namespace std;
using namespace CVC4::kind;
namespace CVC4 {
namespace theory {
namespace sets {
InferenceManager::InferenceManager(Theory& t,
SolverState& s,
ProofNodeManager* pnm)
: InferenceManagerBuffered(t, s, pnm, "theory::sets"), d_state(s)
{
d_true = NodeManager::currentNM()->mkConst(true);
d_false = NodeManager::currentNM()->mkConst(false);
}
bool InferenceManager::assertFactRec(Node fact, InferenceId id, Node exp, int inferType)
{
// should we send this fact out as a lemma?
if ((options::setsInferAsLemmas() && inferType != -1) || inferType == 1)
{
if (d_state.isEntailed(fact, true))
{
return false;
}
Node lem = fact;
if (exp != d_true)
{
lem = NodeManager::currentNM()->mkNode(IMPLIES, exp, fact);
}
addPendingLemma(lem, id);
return true;
}
Trace("sets-fact") << "Assert fact rec : " << fact << ", exp = " << exp
<< std::endl;
if (fact.isConst())
{
// either trivial or a conflict
if (fact == d_false)
{
Trace("sets-lemma") << "Conflict : " << exp << std::endl;
conflict(exp, id);
return true;
}
return false;
}
else if (fact.getKind() == AND
|| (fact.getKind() == NOT && fact[0].getKind() == OR))
{
bool ret = false;
Node f = fact.getKind() == NOT ? fact[0] : fact;
for (unsigned i = 0; i < f.getNumChildren(); i++)
{
Node factc = fact.getKind() == NOT ? f[i].negate() : f[i];
bool tret = assertFactRec(factc, id, exp, inferType);
ret = ret || tret;
if (d_state.isInConflict())
{
return true;
}
}
return ret;
}
bool polarity = fact.getKind() != NOT;
TNode atom = polarity ? fact : fact[0];
if (d_state.isEntailed(atom, polarity))
{
return false;
}
// things we can assert to equality engine
if (atom.getKind() == MEMBER
|| (atom.getKind() == EQUAL && atom[0].getType().isSet()))
{
// send to equality engine
if (assertInternalFact(atom, polarity, id, exp))
{
// return true if this wasn't redundant
return true;
}
}
else
{
// must send as lemma
Node lem = fact;
if (exp != d_true)
{
lem = NodeManager::currentNM()->mkNode(IMPLIES, exp, fact);
}
addPendingLemma(lem, id);
return true;
}
return false;
}
void InferenceManager::assertInference(Node fact,
InferenceId id,
Node exp,
int inferType)
{
if (assertFactRec(fact, id, exp, inferType))
{
Trace("sets-lemma") << "Sets::Lemma : " << fact << " from " << exp << " by "
<< id << std::endl;
Trace("sets-assertion") << "(assert (=> " << exp << " " << fact
<< ")) ; by " << id << std::endl;
}
}
void InferenceManager::assertInference(Node fact,
InferenceId id,
std::vector<Node>& exp,
int inferType)
{
Node exp_n = exp.empty() ? d_true
: (exp.size() == 1
? exp[0]
: NodeManager::currentNM()->mkNode(AND, exp));
assertInference(fact, id, exp_n, inferType);
}
void InferenceManager::assertInference(std::vector<Node>& conc,
InferenceId id,
Node exp,
int inferType)
{
if (!conc.empty())
{
Node fact = conc.size() == 1 ? conc[0]
: NodeManager::currentNM()->mkNode(AND, conc);
assertInference(fact, id, exp, inferType);
}
}
void InferenceManager::assertInference(std::vector<Node>& conc,
InferenceId id,
std::vector<Node>& exp,
int inferType)
{
Node exp_n = exp.empty() ? d_true
: (exp.size() == 1
? exp[0]
: NodeManager::currentNM()->mkNode(AND, exp));
assertInference(conc, id, exp_n, inferType);
}
void InferenceManager::split(Node n, InferenceId id, int reqPol)
{
n = Rewriter::rewrite(n);
Node lem = NodeManager::currentNM()->mkNode(OR, n, n.negate());
// send the lemma
lemma(lem, id);
Trace("sets-lemma") << "Sets::Lemma split : " << lem << std::endl;
if (reqPol != 0)
{
Trace("sets-lemma") << "Sets::Require phase " << n << " " << (reqPol > 0)
<< std::endl;
requirePhase(n, reqPol > 0);
}
}
} // namespace sets
} // namespace theory
} // namespace CVC4
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