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/********************* */
/*! \file theory_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 An inference manager for Theory
**/
#include "theory/theory_inference_manager.h"
#include "theory/theory.h"
#include "theory/uf/equality_engine.h"
using namespace CVC4::kind;
namespace CVC4 {
namespace theory {
TheoryInferenceManager::TheoryInferenceManager(Theory& t,
TheoryState& state,
ProofNodeManager* pnm)
: d_theory(t),
d_theoryState(state),
d_out(t.getOutputChannel()),
d_ee(nullptr),
d_pnm(pnm),
d_keep(t.getSatContext())
{
}
void TheoryInferenceManager::setEqualityEngine(eq::EqualityEngine* ee)
{
d_ee = ee;
// if proofs are enabled, also make a proof equality engine to wrap ee
if (d_pnm != nullptr)
{
d_pfee.reset(new eq::ProofEqEngine(d_theoryState.getSatContext(),
d_theoryState.getUserContext(),
*d_ee,
d_pnm));
}
}
void TheoryInferenceManager::conflictEqConstantMerge(TNode a, TNode b)
{
if (!d_theoryState.isInConflict())
{
TrustNode tconf = explainConflictEqConstantMerge(a, b);
d_theoryState.notifyInConflict();
d_out.trustedConflict(tconf);
}
}
void TheoryInferenceManager::conflict(TNode conf)
{
if (!d_theoryState.isInConflict())
{
d_theoryState.notifyInConflict();
d_out.conflict(conf);
}
}
void TheoryInferenceManager::trustedConflict(TrustNode tconf)
{
if (!d_theoryState.isInConflict())
{
d_theoryState.notifyInConflict();
d_out.trustedConflict(tconf);
}
}
bool TheoryInferenceManager::propagateLit(TNode lit)
{
// If already in conflict, no more propagation
if (d_theoryState.isInConflict())
{
return false;
}
// Propagate out
bool ok = d_out.propagate(lit);
if (!ok)
{
d_theoryState.notifyInConflict();
}
return ok;
}
TrustNode TheoryInferenceManager::explainLit(TNode lit)
{
if (d_pfee != nullptr)
{
return d_pfee->explain(lit);
}
if (d_ee != nullptr)
{
Node exp = d_ee->mkExplainLit(lit);
return TrustNode::mkTrustPropExp(lit, exp, nullptr);
}
Unimplemented() << "Inference manager for " << d_theory.getId()
<< " was asked to explain a propagation but doesn't have an "
"equality engine or implement the "
"TheoryInferenceManager::explainLit interface!";
}
TrustNode TheoryInferenceManager::explainConflictEqConstantMerge(TNode a,
TNode b)
{
Node lit = a.eqNode(b);
if (d_pfee != nullptr)
{
return d_pfee->explain(lit);
}
if (d_ee != nullptr)
{
Node conf = d_ee->mkExplainLit(lit);
return TrustNode::mkTrustConflict(conf, nullptr);
}
Unimplemented() << "Inference manager for " << d_theory.getId()
<< " mkTrustedConflictEqConstantMerge";
}
LemmaStatus TheoryInferenceManager::lemma(TNode lem, LemmaProperty p)
{
return d_out.lemma(lem, p);
}
LemmaStatus TheoryInferenceManager::trustedLemma(const TrustNode& tlem,
LemmaProperty p)
{
return d_out.trustedLemma(tlem, p);
}
void TheoryInferenceManager::assertInternalFact(TNode atom, bool pol, TNode exp)
{
processInternalFact(atom, pol, PfRule::UNKNOWN, {exp}, {}, nullptr);
}
void TheoryInferenceManager::assertInternalFact(TNode atom,
bool pol,
PfRule id,
const std::vector<Node>& exp,
const std::vector<Node>& args)
{
Assert(id != PfRule::UNKNOWN);
processInternalFact(atom, pol, id, exp, args, nullptr);
}
void TheoryInferenceManager::assertInternalFact(TNode atom,
bool pol,
const std::vector<Node>& exp,
ProofGenerator* pg)
{
Assert(pg != nullptr);
processInternalFact(atom, pol, PfRule::ASSUME, exp, {}, pg);
}
void TheoryInferenceManager::processInternalFact(TNode atom,
bool pol,
PfRule id,
const std::vector<Node>& exp,
const std::vector<Node>& args,
ProofGenerator* pg)
{
// make the node corresponding to the explanation
Node expn = NodeManager::currentNM()->mkAnd(exp);
// call the pre-notify fact method with preReg = false, isInternal = true
if (d_theory.preNotifyFact(atom, pol, expn, false, true))
{
// handled in a theory-specific way that doesn't require equality engine
return;
}
Assert(d_ee != nullptr);
Trace("infer-manager") << "TheoryInferenceManager::assertInternalFact: "
<< expn << std::endl;
// Now, assert the fact. How to do so depends on whether proofs are enabled.
// If no proof production, or no proof rule was given
if (d_pfee == nullptr || id == PfRule::UNKNOWN)
{
if (atom.getKind() == kind::EQUAL)
{
d_ee->assertEquality(atom, pol, expn);
}
else
{
d_ee->assertPredicate(atom, pol, expn);
}
// Must reference count the equality and its explanation, which is not done
// by the equality engine. Notice that we do *not* need to do this for
// external assertions, which enter as facts in theory check. This is also
// not done if we are asserting to the proof equality engine, which does
// this caching itself within ProofEqEngine::assertFact.
d_keep.insert(atom);
d_keep.insert(expn);
}
else
{
// Note that we reconstruct the original literal lit here, since both the
// original literal is needed for bookkeeping proofs. It is possible to
// optimize this so that a few less nodes are created, but at the cost
// of a more verbose interface to proof equality engine.
Node lit = pol ? Node(atom) : atom.notNode();
if (pg != nullptr)
{
// use the proof generator interface
d_pfee->assertFact(lit, expn, pg);
}
else
{
// use the explict proof step interface
d_pfee->assertFact(lit, id, expn, args);
}
}
// call the notify fact method with isInternal = true
d_theory.notifyFact(atom, pol, expn, true);
Trace("infer-manager")
<< "TheoryInferenceManager::finished assertInternalFact" << std::endl;
}
void TheoryInferenceManager::explain(TNode n, std::vector<TNode>& assumptions)
{
if (n.getKind() == kind::AND)
{
for (const Node& nc : n)
{
d_ee->explainLit(nc, assumptions);
}
}
else
{
d_ee->explainLit(n, assumptions);
}
}
Node TheoryInferenceManager::mkExplain(TNode n)
{
std::vector<TNode> assumptions;
explain(n, assumptions);
return NodeManager::currentNM()->mkAnd(assumptions);
}
} // namespace theory
} // namespace CVC4
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