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-rw-r--r--src/theory/quantifiers/inst_propagator.cpp761
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diff --git a/src/theory/quantifiers/inst_propagator.cpp b/src/theory/quantifiers/inst_propagator.cpp
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+/********************* */
+/*! \file inst_propagator.cpp
+ ** \verbatim
+ ** Top contributors (to current version):
+ ** Andrew Reynolds
+ ** This file is part of the CVC4 project.
+ ** Copyright (c) 2009-2016 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
+ **
+ ** Propagate mechanism for instantiations
+ **/
+
+#include <vector>
+
+#include "theory/quantifiers/inst_propagator.h"
+#include "theory/rewriter.h"
+#include "theory/quantifiers/term_database.h"
+
+using namespace CVC4;
+using namespace std;
+using namespace CVC4::theory;
+using namespace CVC4::theory::quantifiers;
+using namespace CVC4::kind;
+
+
+EqualityQueryInstProp::EqualityQueryInstProp( QuantifiersEngine* qe ) : d_qe( qe ){
+ d_true = NodeManager::currentNM()->mkConst( true );
+ d_false = NodeManager::currentNM()->mkConst( false );
+}
+
+bool EqualityQueryInstProp::reset( Theory::Effort e ) {
+ d_uf.clear();
+ d_uf_exp.clear();
+ d_diseq_list.clear();
+ return true;
+}
+
+/** contains term */
+bool EqualityQueryInstProp::hasTerm( Node a ) {
+ if( getEngine()->hasTerm( a ) ){
+ return true;
+ }else{
+ std::vector< Node > exp;
+ Node ar = getUfRepresentative( a, exp );
+ return !ar.isNull() && getEngine()->hasTerm( ar );
+ }
+}
+
+/** get the representative of the equivalence class of a */
+Node EqualityQueryInstProp::getRepresentative( Node a ) {
+ if( getEngine()->hasTerm( a ) ){
+ a = getEngine()->getRepresentative( a );
+ }
+ std::vector< Node > exp;
+ Node ar = getUfRepresentative( a, exp );
+ return ar.isNull() ? a : ar;
+}
+
+/** returns true if a and b are equal in the current context */
+bool EqualityQueryInstProp::areEqual( Node a, Node b ) {
+ if( a==b ){
+ return true;
+ }else{
+ eq::EqualityEngine* ee = getEngine();
+ if( ee->hasTerm( a ) && ee->hasTerm( b ) ){
+ if( ee->areEqual( a, b ) ){
+ return true;
+ }
+ }
+ return false;
+ }
+}
+
+/** returns true is a and b are disequal in the current context */
+bool EqualityQueryInstProp::areDisequal( Node a, Node b ) {
+ if( a==b ){
+ return false;
+ }else{
+ eq::EqualityEngine* ee = getEngine();
+ if( ee->hasTerm( a ) && ee->hasTerm( b ) ){
+ if( ee->areDisequal( a, b, false ) ){
+ return true;
+ }
+ }
+ return false;
+ }
+}
+
+/** get the equality engine associated with this query */
+eq::EqualityEngine* EqualityQueryInstProp::getEngine() {
+ return d_qe->getMasterEqualityEngine();
+}
+
+/** get the equivalence class of a */
+void EqualityQueryInstProp::getEquivalenceClass( Node a, std::vector< Node >& eqc ) {
+ //TODO?
+}
+
+TNode EqualityQueryInstProp::getCongruentTerm( Node f, std::vector< TNode >& args ) {
+ TNode t = d_qe->getTermDatabase()->getCongruentTerm( f, args );
+ if( !t.isNull() ){
+ return t;
+ }else{
+ //TODO?
+ return TNode::null();
+ }
+}
+
+Node EqualityQueryInstProp::getRepresentativeExp( Node a, std::vector< Node >& exp ) {
+ bool engine_has_a = getEngine()->hasTerm( a );
+ if( engine_has_a ){
+ a = getEngine()->getRepresentative( a );
+ }
+ //get union find representative, if this occurs in the equality engine, return it
+ unsigned prev_size = exp.size();
+ Node ar = getUfRepresentative( a, exp );
+ if( !ar.isNull() ){
+ if( engine_has_a || getEngine()->hasTerm( ar ) ){
+ Assert( getEngine()->hasTerm( ar ) );
+ Assert( getEngine()->getRepresentative( ar )==ar );
+ return ar;
+ }
+ }else{
+ if( engine_has_a ){
+ return a;
+ }
+ }
+ //retract explanation
+ while( exp.size()>prev_size ){
+ exp.pop_back();
+ }
+ return Node::null();
+}
+
+bool EqualityQueryInstProp::areEqualExp( Node a, Node b, std::vector< Node >& exp ) {
+ if( areEqual( a, b ) ){
+ return true;
+ }else{
+ std::vector< Node > exp_a;
+ Node ar = getUfRepresentative( a, exp_a );
+ if( !ar.isNull() ){
+ std::vector< Node > exp_b;
+ if( ar==getUfRepresentative( b, exp_b ) ){
+ merge_exp( exp, exp_a );
+ merge_exp( exp, exp_b );
+ return true;
+ }
+ }
+ return false;
+ }
+}
+
+bool EqualityQueryInstProp::areDisequalExp( Node a, Node b, std::vector< Node >& exp ) {
+ if( areDisequal( a, b ) ){
+ return true;
+ }else{
+ //Assert( getRepresentative( a )==a );
+ //Assert( getRepresentative( b )==b );
+ std::map< Node, std::vector< Node > >::iterator itd = d_diseq_list[a].find( b );
+ if( itd!=d_diseq_list[a].end() ){
+ exp.insert( exp.end(), itd->second.begin(), itd->second.end() );
+ return true;
+ }else{
+ return false;
+ }
+ }
+}
+
+Node EqualityQueryInstProp::getUfRepresentative( Node a, std::vector< Node >& exp ) {
+ Assert( exp.empty() );
+ std::map< Node, Node >::iterator it = d_uf.find( a );
+ if( it!=d_uf.end() ){
+ if( it->second==a ){
+ Assert( d_uf_exp[ a ].empty() );
+ return it->second;
+ }else{
+ Node m = getUfRepresentative( it->second, exp );
+ Assert( !m.isNull() );
+ if( m!=it->second ){
+ //update union find
+ d_uf[ a ] = m;
+ //update explanation : merge the explanation of the parent
+ merge_exp( d_uf_exp[ a ], exp );
+ Trace("qip-eq") << "EqualityQueryInstProp::getUfRepresentative : merge " << a << " -> " << m << ", exp size=" << d_uf_exp[ a ].size() << std::endl;
+ }
+ //add current explanation to exp: note that exp is a subset of d_uf_exp[ a ], reset
+ exp.clear();
+ exp.insert( exp.end(), d_uf_exp[ a ].begin(), d_uf_exp[ a ].end() );
+ return m;
+ }
+ }else{
+ return Node::null();
+ }
+}
+
+// set a == b with reason, return status, modify a and b to representatives pre-merge
+int EqualityQueryInstProp::setEqual( Node& a, Node& b, bool pol, std::vector< Node >& reason ) {
+ if( a==b ){
+ return pol ? STATUS_NONE : STATUS_CONFLICT;
+ }
+ int status = pol ? STATUS_MERGED_UNKNOWN : STATUS_NONE;
+ Trace("qip-eq") << "EqualityQueryInstProp::setEqual " << a << ", " << b << ", pol = " << pol << ", reason size = " << reason.size() << std::endl;
+ //get the representative for a
+ std::vector< Node > exp_a;
+ Node ar = getUfRepresentative( a, exp_a );
+ if( ar.isNull() ){
+ Assert( exp_a.empty() );
+ ar = a;
+ }
+ if( ar==b ){
+ Trace("qip-eq") << "EqualityQueryInstProp::setEqual : already equal" << std::endl;
+ if( pol ){
+ return STATUS_NONE;
+ }else{
+ merge_exp( reason, exp_a );
+ return STATUS_CONFLICT;
+ }
+ }
+ bool swap = false;
+ //get the representative for b
+ std::vector< Node > exp_b;
+ Node br = getUfRepresentative( b, exp_b );
+ if( br.isNull() ){
+ Assert( exp_b.empty() );
+ br = b;
+ if( !getEngine()->hasTerm( br ) ){
+ if( ar!=a || getEngine()->hasTerm( ar ) ){
+ swap = true;
+ }
+ }else{
+ if( getEngine()->hasTerm( ar ) ){
+ status = STATUS_MERGED_KNOWN;
+ }
+ }
+ }else{
+ if( ar==br ){
+ Trace("qip-eq") << "EqualityQueryInstProp::setEqual : already equal" << std::endl;
+ if( pol ){
+ return STATUS_NONE;
+ }else{
+ merge_exp( reason, exp_a );
+ merge_exp( reason, exp_b );
+ return STATUS_CONFLICT;
+ }
+ }else if( getEngine()->hasTerm( ar ) ){
+ if( getEngine()->hasTerm( br ) ){
+ status = STATUS_MERGED_KNOWN;
+ }else{
+ swap = true;
+ }
+ }
+ }
+
+ if( swap ){
+ //swap
+ Node temp_r = ar;
+ ar = br;
+ br = temp_r;
+ }
+
+ Assert( !getEngine()->hasTerm( ar ) || getEngine()->hasTerm( br ) );
+ Assert( ar!=br );
+
+ std::vector< Node > exp_d;
+ if( areDisequalExp( ar, br, exp_d ) ){
+ if( pol ){
+ merge_exp( reason, exp_b );
+ merge_exp( reason, exp_b );
+ merge_exp( reason, exp_d );
+ return STATUS_CONFLICT;
+ }else{
+ return STATUS_NONE;
+ }
+ }else{
+ if( pol ){
+ //update the union find
+ Assert( d_uf_exp[ar].empty() );
+ Assert( d_uf_exp[br].empty() );
+
+ d_uf[ar] = br;
+ merge_exp( d_uf_exp[ar], exp_a );
+ merge_exp( d_uf_exp[ar], exp_b );
+ merge_exp( d_uf_exp[ar], reason );
+
+ d_uf[br] = br;
+ d_uf_exp[br].clear();
+
+ Trace("qip-eq") << "EqualityQueryInstProp::setEqual : merge " << ar << " -> " << br << ", exp size = " << d_uf_exp[ar].size() << ", status = " << status << std::endl;
+ a = ar;
+ b = br;
+
+ //carry disequality list
+ std::map< Node, std::map< Node, std::vector< Node > > >::iterator itd = d_diseq_list.find( ar );
+ if( itd!=d_diseq_list.end() ){
+ for( std::map< Node, std::vector< Node > >::iterator itdd = itd->second.begin(); itdd != itd->second.end(); ++itdd ){
+ Node d = itdd->first;
+ if( d_diseq_list[br].find( d )==d_diseq_list[br].end() ){
+ merge_exp( d_diseq_list[br][d], itdd->second );
+ merge_exp( d_diseq_list[br][d], d_uf_exp[ar] );
+ }
+ }
+ }
+
+ return status;
+ }else{
+ Trace("qip-eq") << "EqualityQueryInstProp::setEqual : disequal " << ar << " <> " << br << std::endl;
+ Assert( d_diseq_list[ar].find( br )==d_diseq_list[ar].end() );
+ Assert( d_diseq_list[br].find( ar )==d_diseq_list[br].end() );
+
+ merge_exp( d_diseq_list[ar][br], reason );
+ merge_exp( d_diseq_list[br][ar], reason );
+ return STATUS_NONE;
+ }
+ }
+}
+
+void EqualityQueryInstProp::addArgument( std::vector< Node >& args, std::vector< Node >& props, Node n, bool is_prop, bool pol ) {
+ if( is_prop ){
+ if( isLiteral( n ) ){
+ props.push_back( pol ? n : n.negate() );
+ return;
+ }
+ }
+ args.push_back( n );
+}
+
+bool EqualityQueryInstProp::isLiteral( Node n ) {
+ Kind ak = n.getKind()==NOT ? n[0].getKind() : n.getKind();
+ Assert( ak!=NOT );
+ return ak!=AND && ak!=OR && ak!=IFF && ak!=ITE;
+}
+
+//this is identical to TermDb::evaluateTerm2, but tracks more information
+Node EqualityQueryInstProp::evaluateTermExp( Node n, std::vector< Node >& exp, std::map< Node, Node >& visited, bool hasPol, bool pol,
+ std::map< Node, bool >& watch_list_out, std::vector< Node >& props ) {
+ std::map< Node, Node >::iterator itv = visited.find( n );
+ if( itv != visited.end() ){
+ return itv->second;
+ }else{
+ visited[n] = n;
+ Trace("qip-eval") << "evaluate term : " << n << std::endl;
+ std::vector< Node > exp_n;
+ Node ret = getRepresentativeExp( n, exp_n );
+ if( ret.isNull() ){
+ //term is not known to be equal to a representative in equality engine, evaluate it
+ Kind k = n.getKind();
+ if( k==FORALL ){
+ ret = Node::null();
+ }else{
+ std::map< Node, bool > watch_list_out_curr;
+ TNode f = d_qe->getTermDatabase()->getMatchOperator( n );
+ std::vector< Node > args;
+ bool ret_set = false;
+ bool childChanged = false;
+ int abort_i = -1;
+ //get the child entailed polarity
+ Assert( n.getKind()!=IMPLIES );
+ bool newHasPol, newPol;
+ QuantPhaseReq::getEntailPolarity( n, 0, hasPol, pol, newHasPol, newPol );
+ //for each child
+ for( unsigned i=0; i<n.getNumChildren(); i++ ){
+ Node c = evaluateTermExp( n[i], exp, visited, newHasPol, newPol, watch_list_out_curr, props );
+ if( c.isNull() ){
+ ret = Node::null();
+ ret_set = true;
+ break;
+ }else if( c==d_true || c==d_false ){
+ //short-circuiting
+ if( k==kind::AND || k==kind::OR ){
+ if( (k==kind::AND)==(c==d_false) ){
+ ret = c;
+ ret_set = true;
+ break;
+ }else{
+ //redundant
+ c = Node::null();
+ childChanged = true;
+ }
+ }else if( k==kind::ITE && i==0 ){
+ Assert( watch_list_out_curr.empty() );
+ ret = evaluateTermExp( n[ c==d_true ? 1 : 2], exp, visited, hasPol, pol, watch_list_out_curr, props );
+ ret_set = true;
+ break;
+ }else if( k==kind::NOT ){
+ ret = c==d_true ? d_false : d_true;
+ ret_set = true;
+ break;
+ }
+ }
+ if( !c.isNull() ){
+ childChanged = childChanged || n[i]!=c;
+ if( !f.isNull() && !watch_list_out_curr.empty() ){
+ // we are done if this is an UF application and an argument is unevaluated
+ args.push_back( c );
+ abort_i = i;
+ break;
+ }else if( ( k==kind::AND || k==kind::OR ) ){
+ if( c.getKind()==k ){
+ //flatten
+ for( unsigned j=0; j<c.getNumChildren(); j++ ){
+ addArgument( args, props, c[j], newHasPol, newPol );
+ }
+ }else{
+ addArgument( args, props, c, newHasPol, newPol );
+ }
+ //if we are in a branching position
+ if( hasPol && !newHasPol && args.size()>=2 ){
+ //we are done if at least two args are unevaluated
+ abort_i = i;
+ break;
+ }
+ }else if( k==kind::ITE ){
+ //we are done if we are ITE and condition is unevaluated
+ Assert( i==0 );
+ args.push_back( c );
+ abort_i = i;
+ break;
+ }else{
+ args.push_back( c );
+ }
+ }
+ }
+ //add remaining children if we aborted
+ if( abort_i!=-1 ){
+ for( int i=(abort_i+1); i<(int)n.getNumChildren(); i++ ){
+ args.push_back( n[i] );
+ }
+ }
+ //copy over the watch list
+ for( std::map< Node, bool >::iterator itc = watch_list_out_curr.begin(); itc != watch_list_out_curr.end(); ++itc ){
+ watch_list_out[itc->first] = itc->second;
+ }
+
+ //if we have not short-circuited evaluation
+ if( !ret_set ){
+ //if it is an indexed term, return the congruent term
+ if( !f.isNull() && watch_list_out.empty() ){
+ std::vector< TNode > t_args;
+ for( unsigned i=0; i<args.size(); i++ ) {
+ t_args.push_back( args[i] );
+ }
+ Assert( args.size()==n.getNumChildren() );
+ //args contains terms known by the equality engine
+ TNode nn = getCongruentTerm( f, t_args );
+ Trace("qip-eval") << " got congruent term " << nn << " from DB for " << n << std::endl;
+ if( !nn.isNull() ){
+ //successfully constructed representative in EE
+ Assert( exp_n.empty() );
+ ret = getRepresentativeExp( nn, exp_n );
+ Trace("qip-eval") << "return rep, exp size = " << exp_n.size() << std::endl;
+ merge_exp( exp, exp_n );
+ ret_set = true;
+ Assert( !ret.isNull() );
+ }
+ }
+ if( !ret_set ){
+ if( childChanged ){
+ Trace("qip-eval") << "return rewrite" << std::endl;
+ if( ( k==kind::AND || k==kind::OR ) ){
+ if( args.empty() ){
+ ret = k==kind::AND ? d_true : d_false;
+ ret_set = true;
+ }else if( args.size()==1 ){
+ ret = args[0];
+ ret_set = true;
+ }
+ }else{
+ Assert( args.size()==n.getNumChildren() );
+ }
+ if( !ret_set ){
+ if( n.getMetaKind() == kind::metakind::PARAMETERIZED ){
+ args.insert( args.begin(), n.getOperator() );
+ }
+ ret = NodeManager::currentNM()->mkNode( k, args );
+ ret = Rewriter::rewrite( ret );
+ //re-evaluate
+ Node ret_eval = getRepresentativeExp( ret, exp_n );
+ if( !ret_eval.isNull() ){
+ ret = ret_eval;
+ watch_list_out.clear();
+ }else{
+ watch_list_out[ret] = true;
+ }
+ }
+ }else{
+ ret = n;
+ watch_list_out[ret] = true;
+ }
+ }
+ }
+ }
+ }else{
+ Trace("qip-eval") << "...exists in ee, return rep, exp size = " << exp_n.size() << std::endl;
+ merge_exp( exp, exp_n );
+ }
+ Trace("qip-eval") << "evaluated term : " << n << ", got : " << ret << ", exp size = " << exp.size() << std::endl;
+ visited[n] = ret;
+ return ret;
+ }
+}
+
+void EqualityQueryInstProp::merge_exp( std::vector< Node >& v, std::vector< Node >& v_to_merge, int up_to_size ) {
+ //TODO : optimize
+ if( v.empty() ){
+ Assert( up_to_size==-1 || up_to_size==(int)v_to_merge.size() );
+ v.insert( v.end(), v_to_merge.begin(), v_to_merge.end() );
+ }else{
+ //std::vector< Node >::iterator v_end = v.end();
+ up_to_size = up_to_size==-1 ? (int)v_to_merge.size() : up_to_size;
+ for( int j=0; j<up_to_size; j++ ){
+ if( std::find( v.begin(), v.end(), v_to_merge[j] )==v.end() ){
+ v.push_back( v_to_merge[j] );
+ }
+ }
+ }
+}
+
+
+void InstPropagator::InstInfo::init( Node q, Node lem, std::vector< Node >& terms, Node body ) {
+ d_active = true;
+ //information about the instance
+ d_q = q;
+ d_lem = lem;
+ Assert( d_terms.empty() );
+ d_terms.insert( d_terms.end(), terms.begin(), terms.end() );
+ //the current lemma
+ d_curr = body;
+ d_curr_exp.push_back( body );
+}
+
+InstPropagator::InstPropagator( QuantifiersEngine* qe ) :
+d_qe( qe ), d_notify(*this), d_qy( qe ){
+}
+
+bool InstPropagator::reset( Theory::Effort e ) {
+ d_icount = 1;
+ d_ii.clear();
+ for( unsigned i=0; i<2; i++ ){
+ d_conc_to_id[i].clear();
+ d_conc_to_id[i][d_qy.d_true] = 0;
+ }
+ d_conflict = false;
+ d_watch_list.clear();
+ d_update_list.clear();
+ d_relevant_inst.clear();
+ return d_qy.reset( e );
+}
+
+bool InstPropagator::notifyInstantiation( unsigned quant_e, Node q, Node lem, std::vector< Node >& terms, Node body ) {
+ if( !d_conflict ){
+ if( Trace.isOn("qip-prop") ){
+ Trace("qip-prop") << "InstPropagator:: Notify instantiation " << q << " : " << std::endl;
+ for( unsigned i=0; i<terms.size(); i++ ){
+ Trace("qip-prop") << " " << terms[i] << std::endl;
+ }
+ }
+ unsigned id = d_icount;
+ d_icount++;
+ Trace("qip-prop") << "...assign id=" << id << std::endl;
+ d_ii[id].init( q, lem, terms, body );
+ //initialize the information
+ if( cacheConclusion( id, body ) ){
+ Assert( d_update_list.empty() );
+ d_update_list.push_back( id );
+ bool firstTime = true;
+ //update infos in the update list until empty
+ do {
+ unsigned uid = d_update_list.back();
+ d_update_list.pop_back();
+ if( d_ii[uid].d_active ){
+ update( uid, d_ii[uid], firstTime );
+ }
+ firstTime = false;
+ }while( !d_conflict && !d_update_list.empty() );
+ }else{
+ d_ii[id].d_active = false;
+ Trace("qip-prop") << "...duplicate." << std::endl;
+ }
+ Trace("qip-prop") << "...finished notify instantiation." << std::endl;
+ return !d_conflict;
+ }else{
+ Assert( false );
+ return true;
+ }
+}
+
+bool InstPropagator::update( unsigned id, InstInfo& ii, bool firstTime ) {
+ Assert( !d_conflict );
+ Assert( ii.d_active );
+ Trace("qip-prop-debug") << "Update info [" << id << "]..." << std::endl;
+ //update the evaluation of the current lemma
+ std::map< Node, Node > visited;
+ std::map< Node, bool > watch_list;
+ std::vector< Node > props;
+ Node eval = d_qy.evaluateTermExp( ii.d_curr, ii.d_curr_exp, visited, true, true, watch_list, props );
+ if( eval.isNull() ){
+ ii.d_active = false;
+ }else if( firstTime || eval!=ii.d_curr ){
+ if( EqualityQueryInstProp::isLiteral( eval ) ){
+ props.push_back( eval );
+ eval = d_qy.d_true;
+ watch_list.clear();
+ }
+ if( Trace.isOn("qip-prop") ){
+ Trace("qip-prop") << "Update info [" << id << "]..." << std::endl;
+ Trace("qip-prop") << "...updated lemma " << ii.d_curr << " -> " << eval << ", exp = ";
+ debugPrintExplanation( ii.d_curr_exp, "qip-prop" );
+ Trace("qip-prop") << std::endl;
+ Trace("qip-prop") << "...watch list: " << std::endl;
+ for( std::map< Node, bool >::iterator itw = watch_list.begin(); itw!=watch_list.end(); ++itw ){
+ Trace("qip-prop") << " " << itw->first << std::endl;
+ }
+ Trace("qip-prop") << "...new propagations: " << std::endl;
+ for( unsigned i=0; i<props.size(); i++ ){
+ Trace("qip-prop") << " " << props[i] << std::endl;
+ }
+ Trace("qip-prop") << std::endl;
+ }
+ //determine the status of eval
+ if( eval==d_qy.d_false ){
+ Assert( props.empty() );
+ //we have inferred a conflict
+ conflict( ii.d_curr_exp );
+ return false;
+ }else{
+ for( unsigned i=0; i<props.size(); i++ ){
+ Trace("qip-prop-debug2") << "Process propagation " << props[i] << std::endl;
+ //if we haven't propagated this literal yet
+ if( cacheConclusion( id, props[i], 1 ) ){
+ Node lit = props[i].getKind()==NOT ? props[i][0] : props[i];
+ bool pol = props[i].getKind()!=NOT;
+ if( lit.getKind()==EQUAL ){
+ propagate( lit[0], lit[1], pol, ii.d_curr_exp );
+ }else{
+ propagate( lit, pol ? d_qy.d_true : d_qy.d_false, true, ii.d_curr_exp );
+ }
+ if( d_conflict ){
+ return false;
+ }
+ }
+ Trace("qip-prop-debug2") << "Done process propagation " << props[i] << std::endl;
+ }
+ //if we have not inferred this conclusion yet
+ if( cacheConclusion( id, eval ) ){
+ ii.d_curr = eval;
+ //update the watch list
+ Trace("qip-prop-debug") << "...updating watch list for [" << id << "], curr is " << ii.d_curr << std::endl;
+ //Here, we need to be notified of enough terms such that if we are not notified, then update( ii ) will return no propagations.
+ // Similar to two-watched literals, but since we are in UF, we need to watch all terms on a complete path of two terms.
+ for( std::map< Node, bool >::iterator itw = watch_list.begin(); itw != watch_list.end(); ++itw ){
+ d_watch_list[ itw->first ][ id ] = true;
+ }
+ }else{
+ Trace("qip-prop-debug") << "...conclusion " << eval << " is duplicate." << std::endl;
+ ii.d_active = false;
+ }
+ }
+ }else{
+ Trace("qip-prop-debug") << "...did not update." << std::endl;
+ }
+ Assert( !d_conflict );
+ return true;
+}
+
+void InstPropagator::propagate( Node a, Node b, bool pol, std::vector< Node >& exp ) {
+ if( Trace.isOn("qip-propagate") ){
+ Trace("qip-propagate") << "* Propagate " << a << ( pol ? " == " : " != " ) << b << ", exp = ";
+ debugPrintExplanation( exp, "qip-propagate" );
+ Trace("qip-propagate") << "..." << std::endl;
+ }
+ //set equal
+ int status = d_qy.setEqual( a, b, pol, exp );
+ if( status==EqualityQueryInstProp::STATUS_NONE ){
+ Trace("qip-prop-debug") << "...already equal/no conflict." << std::endl;
+ return;
+ }else if( status==EqualityQueryInstProp::STATUS_CONFLICT ){
+ Trace("qip-prop-debug") << "...conflict." << std::endl;
+ conflict( exp );
+ return;
+ }
+ if( pol ){
+ if( status==EqualityQueryInstProp::STATUS_MERGED_KNOWN ){
+ Assert( d_qy.getEngine()->hasTerm( a ) );
+ Assert( d_qy.getEngine()->hasTerm( b ) );
+ Trace("qip-prop-debug") << "...equality between known terms." << std::endl;
+ addRelevantInstances( exp, "qip-propagate" );
+ }
+ Trace("qip-prop-debug") << "...merged representatives " << a << " and " << b << std::endl;
+ for( unsigned i=0; i<2; i++ ){
+ //update terms from watched lists
+ Node c = i==0 ? a : b;
+ std::map< Node, std::map< unsigned, bool > >::iterator it = d_watch_list.find( c );
+ if( it!=d_watch_list.end() ){
+ Trace("qip-prop-debug") << "...update ids from watch list of " << c << ", size=" << it->second.size() << "..." << std::endl;
+ for( std::map< unsigned, bool >::iterator itw = it->second.begin(); itw != it->second.end(); ++itw ){
+ unsigned idw = itw->first;
+ if( std::find( d_update_list.begin(), d_update_list.end(), idw )==d_update_list.end() ){
+ Trace("qip-prop-debug") << "...will update " << idw << std::endl;
+ d_update_list.push_back( idw );
+ }
+ }
+ d_watch_list.erase( c );
+ }
+ }
+ }
+}
+
+void InstPropagator::conflict( std::vector< Node >& exp ) {
+ Trace("qip-propagate") << "Conflict, exp size =" << exp.size() << std::endl;
+ d_conflict = true;
+ d_relevant_inst.clear();
+ addRelevantInstances( exp, "qip-propagate" );
+
+ //now, inform quantifiers engine which instances should be retracted
+ Trace("qip-prop-debug") << "...remove instantiation ids : ";
+ for( std::map< unsigned, InstInfo >::iterator it = d_ii.begin(); it != d_ii.end(); ++it ){
+ if( d_relevant_inst.find( it->first )==d_relevant_inst.end() ){
+ if( !d_qe->removeInstantiation( it->second.d_q, it->second.d_lem, it->second.d_terms ) ){
+ Trace("qip-warn") << "WARNING : did not remove instantiation id " << it->first << std::endl;
+ Assert( false );
+ }else{
+ Trace("qip-prop-debug") << it->first << " ";
+ }
+ }else{
+ //mark the quantified formula as relevant
+ d_qe->markRelevant( it->second.d_q );
+ }
+ }
+ Trace("qip-prop-debug") << std::endl;
+ //will interupt the quantifiers engine
+ Trace("quant-engine-conflict") << "-----> InstPropagator::conflict with " << exp.size() << " instances." << std::endl;
+}
+
+bool InstPropagator::cacheConclusion( unsigned id, Node body, int prop_index ) {
+ Assert( prop_index==0 || prop_index==1 );
+ //check if the conclusion is non-redundant
+ if( d_conc_to_id[prop_index].find( body )==d_conc_to_id[prop_index].end() ){
+ d_conc_to_id[prop_index][body] = id;
+ return true;
+ }else{
+ return false;
+ }
+}
+
+void InstPropagator::addRelevantInstances( std::vector< Node >& exp, const char * c ) {
+ for( unsigned i=0; i<exp.size(); i++ ){
+ Assert( d_conc_to_id[0].find( exp[i] )!=d_conc_to_id[0].end() );
+ Trace(c) << " relevant instance id : " << d_conc_to_id[0][ exp[i] ] << std::endl;
+ d_relevant_inst[ d_conc_to_id[0][ exp[i] ] ] = true;
+ }
+}
+
+void InstPropagator::debugPrintExplanation( std::vector< Node >& exp, const char * c ) {
+ for( unsigned i=0; i<exp.size(); i++ ){
+ Assert( d_conc_to_id[0].find( exp[i] )!=d_conc_to_id[0].end() );
+ Trace(c) << d_conc_to_id[0][ exp[i] ] << " ";
+ }
+}
+
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