src/theory/quantifiers_engine.cpp

   1 /*********************                                                        */
   2 /*! \file quantifiers_engine.cpp
   3  ** \verbatim
   4  ** Top contributors (to current version):
   5  **   Andrew Reynolds, Tim King, Morgan Deters
   6  ** This file is part of the CVC4 project.
   7  ** Copyright (c) 2009-2016 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.\endverbatim
  11  **
  12  ** \brief Implementation of quantifiers engine class
  13  **/
  14
  15 #include "theory/quantifiers_engine.h"
  16
  17 #include "options/quantifiers_options.h"
  18 #include "options/uf_options.h"
  19 #include "smt/smt_statistics_registry.h"
  20 #include "theory/arrays/theory_arrays.h"
  21 #include "theory/datatypes/theory_datatypes.h"
  22 #include "theory/quantifiers/alpha_equivalence.h"
  23 #include "theory/quantifiers/ambqi_builder.h"
  24 #include "theory/quantifiers/bounded_integers.h"
  25 #include "theory/quantifiers/ce_guided_instantiation.h"
  26 #include "theory/quantifiers/conjecture_generator.h"
  27 #include "theory/quantifiers/first_order_model.h"
  28 #include "theory/quantifiers/full_model_check.h"
  29 #include "theory/quantifiers/fun_def_engine.h"
  30 #include "theory/quantifiers/inst_strategy_cbqi.h"
  31 #include "theory/quantifiers/inst_strategy_e_matching.h"
  32 #include "theory/quantifiers/instantiation_engine.h"
  33 #include "theory/quantifiers/local_theory_ext.h"
  34 #include "theory/quantifiers/model_engine.h"
  35 #include "theory/quantifiers/quant_conflict_find.h"
  36 #include "theory/quantifiers/quant_equality_engine.h"
  37 #include "theory/quantifiers/quantifiers_rewriter.h"
  38 #include "theory/quantifiers/relevant_domain.h"
  39 #include "theory/quantifiers/rewrite_engine.h"
  40 #include "theory/quantifiers/term_database.h"
  41 #include "theory/quantifiers/trigger.h"
  42 #include "theory/quantifiers/quant_split.h"
  43 #include "theory/quantifiers/anti_skolem.h"
  44 #include "theory/quantifiers/equality_infer.h"
  45 #include "theory/quantifiers/inst_propagator.h"
  46 #include "theory/theory_engine.h"
  47 #include "theory/uf/equality_engine.h"
  48 #include "theory/uf/theory_uf.h"
  49 #include "theory/uf/theory_uf_strong_solver.h"
  50
  51 using namespace std;
  52 using namespace CVC4;
  53 using namespace CVC4::kind;
  54 using namespace CVC4::context;
  55 using namespace CVC4::theory;
  56 using namespace CVC4::theory::inst;
  57
  58 QuantifiersEngine::QuantifiersEngine(context::Context* c, context::UserContext* u, TheoryEngine* te):
  59     d_te( te ),
  60     d_conflict_c(c, false),
  61     //d_quants(u),
  62     d_quants_red(u),
  63     d_lemmas_produced_c(u),
  64     d_skolemized(u),
  65     d_ierCounter_c(c),
  66     //d_ierCounter(c),
  67     //d_ierCounter_lc(c),
  68     //d_ierCounterLastLc(c),
  69     d_presolve(u, true),
  70     d_presolve_in(u),
  71     d_presolve_cache(u),
  72     d_presolve_cache_wq(u),
  73     d_presolve_cache_wic(u){
  74   //utilities
  75   d_eq_query = new EqualityQueryQuantifiersEngine( c, this );
  76   d_util.push_back( d_eq_query );
  77
  78   d_term_db = new quantifiers::TermDb( c, u, this );
  79   d_util.push_back( d_term_db );
  80
  81   if( options::instPropagate() ){
  82     d_inst_prop = new quantifiers::InstPropagator( this );
  83     d_util.push_back( d_inst_prop );
  84     d_inst_notify.push_back( d_inst_prop->getInstantiationNotify() );
  85   }else{
  86     d_inst_prop = NULL;
  87   }
  88
  89   d_tr_trie = new inst::TriggerTrie;
  90   d_curr_effort_level = QEFFORT_NONE;
  91   d_conflict = false;
  92   d_hasAddedLemma = false;
  93   //don't add true lemma
  94   d_lemmas_produced_c[d_term_db->d_true] = true;
  95
  96   Trace("quant-engine-debug") << "Initialize quantifiers engine." << std::endl;
  97   Trace("quant-engine-debug") << "Initialize model, mbqi : " << options::mbqiMode() << std::endl;
  98
  99   //the model object
 100   if( options::mbqiMode()==quantifiers::MBQI_FMC ||
 101       options::mbqiMode()==quantifiers::MBQI_FMC_INTERVAL || options::fmfBoundInt() ||
 102       options::mbqiMode()==quantifiers::MBQI_TRUST ){
 103     d_model = new quantifiers::fmcheck::FirstOrderModelFmc( this, c, "FirstOrderModelFmc" );
 104   }else if( options::mbqiMode()==quantifiers::MBQI_ABS ){
 105     d_model = new quantifiers::FirstOrderModelAbs( this, c, "FirstOrderModelAbs" );
 106   }else{
 107     d_model = new quantifiers::FirstOrderModelIG( this, c, "FirstOrderModelIG" );
 108   }
 109   if( options::relevantTriggers() ){
 110     d_quant_rel = new QuantRelevance( false );
 111   }else{
 112     d_quant_rel = NULL;
 113   }
 114
 115   d_qcf = NULL;
 116   d_sg_gen = NULL;
 117   d_inst_engine = NULL;
 118   d_i_cbqi = NULL;
 119   d_qsplit = NULL;
 120   d_anti_skolem = NULL;
 121   d_model_engine = NULL;
 122   d_bint = NULL;
 123   d_rr_engine = NULL;
 124   d_ceg_inst = NULL;
 125   d_lte_part_inst = NULL;
 126   d_alpha_equiv = NULL;
 127   d_fun_def_engine = NULL;
 128   d_uee = NULL;
 129   d_fs = NULL;
 130   d_rel_dom = NULL;
 131   d_builder = NULL;
 132
 133   d_total_inst_count_debug = 0;
 134   //allow theory combination to go first, once initially
 135   d_ierCounter = options::instWhenTcFirst() ? 0 : 1;
 136   d_ierCounter_c = d_ierCounter;
 137   d_ierCounter_lc = 0;
 138   d_ierCounterLastLc = 0;
 139   d_inst_when_phase = 1 + ( options::instWhenPhase()<1 ? 1 : options::instWhenPhase() );
 140 }
 141
 142 QuantifiersEngine::~QuantifiersEngine(){
 143   for(std::map< Node, inst::CDInstMatchTrie* >::iterator
 144       i = d_c_inst_match_trie.begin(), iend = d_c_inst_match_trie.end();
 145       i != iend; ++i)
 146   {
 147     delete (*i).second;
 148   }
 149   d_c_inst_match_trie.clear();
 150
 151   delete d_alpha_equiv;
 152   delete d_builder;
 153   delete d_rr_engine;
 154   delete d_bint;
 155   delete d_model_engine;
 156   delete d_inst_engine;
 157   delete d_qcf;
 158   delete d_quant_rel;
 159   delete d_rel_dom;
 160   delete d_model;
 161   delete d_tr_trie;
 162   delete d_term_db;
 163   delete d_eq_query;
 164   delete d_sg_gen;
 165   delete d_ceg_inst;
 166   delete d_lte_part_inst;
 167   delete d_fun_def_engine;
 168   delete d_uee;
 169   delete d_fs;
 170   delete d_i_cbqi;
 171   delete d_qsplit;
 172   delete d_anti_skolem;
 173   delete d_inst_prop;
 174 }
 175
 176 EqualityQueryQuantifiersEngine* QuantifiersEngine::getEqualityQuery() {
 177   return d_eq_query;
 178 }
 179
 180 context::Context* QuantifiersEngine::getSatContext(){
 181   return d_te->theoryOf( THEORY_QUANTIFIERS )->getSatContext();
 182 }
 183
 184 context::UserContext* QuantifiersEngine::getUserContext(){
 185   return d_te->theoryOf( THEORY_QUANTIFIERS )->getUserContext();
 186 }
 187
 188 OutputChannel& QuantifiersEngine::getOutputChannel(){
 189   return d_te->theoryOf( THEORY_QUANTIFIERS )->getOutputChannel();
 190 }
 191 /** get default valuation for the quantifiers engine */
 192 Valuation& QuantifiersEngine::getValuation(){
 193   return d_te->theoryOf( THEORY_QUANTIFIERS )->getValuation();
 194 }
 195
 196 void QuantifiersEngine::finishInit(){
 197   context::Context * c = getSatContext();
 198   Trace("quant-engine-debug") << "QuantifiersEngine : finishInit " << std::endl;
 199   bool needsBuilder = false;
 200   bool needsRelDom = false;
 201   //add quantifiers modules
 202   if( options::quantConflictFind() || options::quantRewriteRules() ){
 203     d_qcf = new quantifiers::QuantConflictFind( this, c);
 204     d_modules.push_back( d_qcf );
 205   }
 206   if( options::conjectureGen() ){
 207     d_sg_gen = new quantifiers::ConjectureGenerator( this, c );
 208     d_modules.push_back( d_sg_gen );
 209   }
 210   //maintain invariant : either InstantiationEngine or ModelEngine must be in d_modules
 211   if( !options::finiteModelFind() || options::fmfInstEngine() ){
 212     d_inst_engine = new quantifiers::InstantiationEngine( this );
 213     d_modules.push_back(  d_inst_engine );
 214   }
 215   if( options::cbqi() ){
 216     if( options::cbqiSplx() ){
 217       d_i_cbqi = new quantifiers::InstStrategySimplex( (arith::TheoryArith*)getTheoryEngine()->theoryOf( THEORY_ARITH ), this );
 218       d_modules.push_back( d_i_cbqi );
 219     }else{
 220       d_i_cbqi = new quantifiers::InstStrategyCegqi( this );
 221       d_modules.push_back( d_i_cbqi );
 222       if( options::cbqiModel() ){
 223         needsBuilder = true;
 224       }
 225     }
 226   }
 227   //finite model finding
 228   if( options::finiteModelFind() ){
 229     if( options::fmfBoundInt() ){
 230       d_bint = new quantifiers::BoundedIntegers( c, this );
 231       d_modules.push_back( d_bint );
 232     }
 233     d_model_engine = new quantifiers::ModelEngine( c, this );
 234     d_modules.push_back( d_model_engine );
 235     needsBuilder = true;
 236   }
 237   if( options::quantRewriteRules() ){
 238     d_rr_engine = new quantifiers::RewriteEngine( c, this );
 239     d_modules.push_back(d_rr_engine);
 240   }
 241   if( options::ceGuidedInst() ){
 242     d_ceg_inst = new quantifiers::CegInstantiation( this, c );
 243     d_modules.push_back( d_ceg_inst );
 244     needsBuilder = true;
 245   }
 246   if( options::ltePartialInst() ){
 247     d_lte_part_inst = new quantifiers::LtePartialInst( this, c );
 248     d_modules.push_back( d_lte_part_inst );
 249   }
 250   if( ( options::finiteModelFind() && options::quantDynamicSplit()!=quantifiers::QUANT_DSPLIT_MODE_NONE ) ||
 251       options::quantDynamicSplit()==quantifiers::QUANT_DSPLIT_MODE_AGG ){
 252     d_qsplit = new quantifiers::QuantDSplit( this, c );
 253     d_modules.push_back( d_qsplit );
 254   }
 255   if( options::quantAntiSkolem() ){
 256     d_anti_skolem = new quantifiers::QuantAntiSkolem( this );
 257     d_modules.push_back( d_anti_skolem );
 258   }
 259   if( options::quantAlphaEquiv() ){
 260     d_alpha_equiv = new quantifiers::AlphaEquivalence( this );
 261   }
 262   //if( options::funDefs() ){
 263   //  d_fun_def_engine = new quantifiers::FunDefEngine( this, c );
 264   //  d_modules.push_back( d_fun_def_engine );
 265   //}
 266   if( options::quantEqualityEngine() ){
 267     d_uee = new quantifiers::QuantEqualityEngine( this, c );
 268     d_modules.push_back( d_uee );
 269   }
 270   //full saturation : instantiate from relevant domain, then arbitrary terms
 271   if( options::fullSaturateQuant() || options::fullSaturateInst() ){
 272     d_fs = new quantifiers::FullSaturation( this );
 273     d_modules.push_back( d_fs );
 274     needsRelDom = true;
 275   }
 276
 277   if( needsRelDom ){
 278     d_rel_dom = new quantifiers::RelevantDomain( this, d_model );
 279     d_util.push_back( d_rel_dom );
 280   }
 281
 282   if( needsBuilder ){
 283     Trace("quant-engine-debug") << "Initialize model engine, mbqi : " << options::mbqiMode() << " " << options::fmfBoundInt() << std::endl;
 284     if( options::mbqiMode()==quantifiers::MBQI_FMC || options::mbqiMode()==quantifiers::MBQI_FMC_INTERVAL ||
 285         options::mbqiMode()==quantifiers::MBQI_TRUST || options::fmfBoundInt() ){
 286       Trace("quant-engine-debug") << "...make fmc builder." << std::endl;
 287       d_builder = new quantifiers::fmcheck::FullModelChecker( c, this );
 288     }else if( options::mbqiMode()==quantifiers::MBQI_ABS ){
 289       Trace("quant-engine-debug") << "...make abs mbqi builder." << std::endl;
 290       d_builder = new quantifiers::AbsMbqiBuilder( c, this );
 291     }else{
 292       Trace("quant-engine-debug") << "...make default model builder." << std::endl;
 293       d_builder = new quantifiers::QModelBuilderDefault( c, this );
 294     }
 295   }
 296
 297 }
 298
 299 QuantifiersModule * QuantifiersEngine::getOwner( Node q ) {
 300   std::map< Node, QuantifiersModule * >::iterator it = d_owner.find( q );
 301   if( it==d_owner.end() ){
 302     return NULL;
 303   }else{
 304     return it->second;
 305   }
 306 }
 307
 308 void QuantifiersEngine::setOwner( Node q, QuantifiersModule * m, int priority ) {
 309   QuantifiersModule * mo = getOwner( q );
 310   if( mo!=m ){
 311     if( mo!=NULL ){
 312       if( priority<=d_owner_priority[q] ){
 313         Trace("quant-warn") << "WARNING: setting owner of " << q << " to " << ( m ? m->identify() : "null" ) << ", but already has owner " << mo->identify() << " with higher priority!" << std::endl;
 314         return;
 315       }
 316     }
 317     d_owner[q] = m;
 318     d_owner_priority[q] = priority;
 319   }
 320 }
 321
 322 bool QuantifiersEngine::hasOwnership( Node q, QuantifiersModule * m ) {
 323   QuantifiersModule * mo = getOwner( q );
 324   return mo==m || mo==NULL;
 325 }
 326
 327 void QuantifiersEngine::presolve() {
 328   Trace("quant-engine-proc") << "QuantifiersEngine : presolve " << std::endl;
 329   for( unsigned i=0; i<d_modules.size(); i++ ){
 330     d_modules[i]->presolve();
 331   }
 332   d_term_db->presolve();
 333   d_presolve = false;
 334   //add all terms to database
 335   if( options::incrementalSolving() ){
 336     Trace("quant-engine-proc") << "Add presolve cache " << d_presolve_cache.size() << std::endl;
 337     for( unsigned i=0; i<d_presolve_cache.size(); i++ ){
 338       addTermToDatabase( d_presolve_cache[i], d_presolve_cache_wq[i], d_presolve_cache_wic[i] );
 339     }
 340     Trace("quant-engine-proc") << "Done add presolve cache " << std::endl;
 341   }
 342 }
 343
 344 void QuantifiersEngine::check( Theory::Effort e ){
 345   CodeTimer codeTimer(d_statistics.d_time);
 346   if( !getMasterEqualityEngine()->consistent() ){
 347     Trace("quant-engine-debug") << "Master equality engine not consistent, return." << std::endl;
 348     return;
 349   }
 350   bool needsCheck = !d_lemmas_waiting.empty();
 351   unsigned needsModelE = QEFFORT_NONE;
 352   std::vector< QuantifiersModule* > qm;
 353   if( d_model->checkNeeded() ){
 354     needsCheck = needsCheck || e>=Theory::EFFORT_LAST_CALL;  //always need to check at or above last call
 355     for( unsigned i=0; i<d_modules.size(); i++ ){
 356       if( d_modules[i]->needsCheck( e ) ){
 357         qm.push_back( d_modules[i] );
 358         needsCheck = true;
 359         //can only request model at last call since theory combination can find inconsistencies
 360         if( e>=Theory::EFFORT_LAST_CALL ){
 361           unsigned me = d_modules[i]->needsModel( e );
 362           needsModelE = me<needsModelE ? me : needsModelE;
 363         }
 364       }
 365     }
 366   }
 367
 368   d_conflict = false;
 369   d_hasAddedLemma = false;
 370   bool setIncomplete = false;
 371   if( e==Theory::EFFORT_LAST_CALL ){
 372     //sources of incompleteness
 373     if( d_lte_part_inst && d_lte_part_inst->wasInvoked() ){
 374       Trace("quant-engine-debug") << "Set incomplete due to LTE partial instantiation." << std::endl;
 375       setIncomplete = true;
 376     }
 377   }
 378   bool usedModelBuilder = false;
 379
 380   Trace("quant-engine-debug2") << "Quantifiers Engine call to check, level = " << e << ", needsCheck=" << needsCheck << std::endl;
 381   if( needsCheck ){
 382     //this will fail if a set of instances is marked as a conflict, but is not
 383     Assert( !d_conflict_c.get() );
 384     //flush previous lemmas (for instance, if was interupted), or other lemmas to process
 385     flushLemmas();
 386     if( d_hasAddedLemma ){
 387       return;
 388     }
 389     if( !d_recorded_inst.empty() ){
 390       Trace("quant-engine-debug") << "Removing " << d_recorded_inst.size() << " instantiations..." << std::endl;
 391       //remove explicitly recorded instantiations
 392       for( unsigned i=0; i<d_recorded_inst.size(); i++ ){
 393         removeInstantiationInternal( d_recorded_inst[i].first, d_recorded_inst[i].second );
 394       }
 395       d_recorded_inst.clear();
 396     }
 397
 398     double clSet = 0;
 399     if( Trace.isOn("quant-engine") ){
 400       clSet = double(clock())/double(CLOCKS_PER_SEC);
 401       Trace("quant-engine") << ">>>>> Quantifiers Engine Round, effort = " << e << " <<<<<" << std::endl;
 402     }
 403
 404     if( Trace.isOn("quant-engine-debug") ){
 405       Trace("quant-engine-debug") << "Quantifiers Engine check, level = " << e << std::endl;
 406       Trace("quant-engine-debug") << "  depth : " << d_ierCounter_c << std::endl;
 407       Trace("quant-engine-debug") << "  modules to check : ";
 408       for( unsigned i=0; i<qm.size(); i++ ){
 409         Trace("quant-engine-debug") << qm[i]->identify() << " ";
 410       }
 411       Trace("quant-engine-debug") << std::endl;
 412       Trace("quant-engine-debug") << "  # quantified formulas = " << d_model->getNumAssertedQuantifiers() << std::endl;
 413       if( !d_lemmas_waiting.empty() ){
 414         Trace("quant-engine-debug") << "  lemmas waiting = " << d_lemmas_waiting.size() << std::endl;
 415       }
 416       Trace("quant-engine-debug") << "  Theory engine finished : " << !d_te->needCheck() << std::endl;
 417       Trace("quant-engine-debug") << "  Needs model effort : " << needsModelE << std::endl;
 418     }
 419     if( Trace.isOn("quant-engine-ee-pre") ){
 420       Trace("quant-engine-ee-pre") << "Equality engine (pre-inference): " << std::endl;
 421       debugPrintEqualityEngine( "quant-engine-ee-pre" );
 422     }
 423     if( Trace.isOn("quant-engine-assert") ){
 424       Trace("quant-engine-assert") << "Assertions : " << std::endl;
 425       getTheoryEngine()->printAssertions("quant-engine-assert");
 426     }
 427
 428     //reset utilities
 429     Trace("quant-engine-debug") << "Resetting all utilities..." << std::endl;
 430     for( unsigned i=0; i<d_util.size(); i++ ){
 431       Trace("quant-engine-debug2") << "Reset " << d_util[i]->identify().c_str() << "..." << std::endl;
 432       if( !d_util[i]->reset( e ) ){
 433         flushLemmas();
 434         if( d_hasAddedLemma ){
 435           return;
 436         }else{
 437           //should only fail reset if added a lemma
 438           Assert( false );
 439         }
 440       }
 441     }
 442
 443     if( Trace.isOn("quant-engine-ee") ){
 444       Trace("quant-engine-ee") << "Equality engine : " << std::endl;
 445       debugPrintEqualityEngine( "quant-engine-ee" );
 446     }
 447
 448     //reset the model
 449     Trace("quant-engine-debug") << "Reset model..." << std::endl;
 450     d_model->reset_round();
 451
 452     //reset the modules
 453     Trace("quant-engine-debug") << "Resetting all modules..." << std::endl;
 454     for( unsigned i=0; i<d_modules.size(); i++ ){
 455       Trace("quant-engine-debug2") << "Reset " << d_modules[i]->identify().c_str() << std::endl;
 456       d_modules[i]->reset_round( e );
 457     }
 458     Trace("quant-engine-debug") << "Done resetting all modules." << std::endl;
 459     //reset may have added lemmas
 460     flushLemmas();
 461     if( d_hasAddedLemma ){
 462       return;
 463     }
 464
 465     if( e==Theory::EFFORT_LAST_CALL ){
 466       //if effort is last call, try to minimize model first
 467       //uf::StrongSolverTheoryUF * ufss = ((uf::TheoryUF*)getTheoryEngine()->theoryOf( THEORY_UF ))->getStrongSolver();
 468       //if( ufss && !ufss->minimize() ){ return; }
 469       ++(d_statistics.d_instantiation_rounds_lc);
 470     }else if( e==Theory::EFFORT_FULL ){
 471       ++(d_statistics.d_instantiation_rounds);
 472     }
 473     Trace("quant-engine-debug") << "Check modules that needed check..." << std::endl;
 474     for( unsigned quant_e = QEFFORT_CONFLICT; quant_e<=QEFFORT_LAST_CALL; quant_e++ ){
 475       d_curr_effort_level = quant_e;
 476       bool success = true;
 477       //build the model if any module requested it
 478       if( needsModelE==quant_e ){
 479         Assert( d_builder!=NULL );
 480         Trace("quant-engine-debug") << "Build model..." << std::endl;
 481         usedModelBuilder = true;
 482         d_builder->d_addedLemmas = 0;
 483         d_builder->buildModel( d_model, false );
 484         //we are done if model building was unsuccessful
 485         if( d_builder->d_addedLemmas>0 ){
 486           success = false;
 487         }
 488       }
 489       if( success ){
 490         //check each module
 491         for( unsigned i=0; i<qm.size(); i++ ){
 492           Trace("quant-engine-debug") << "Check " << qm[i]->identify().c_str() << " at effort " << quant_e << "..." << std::endl;
 493           qm[i]->check( e, quant_e );
 494           if( d_conflict ){
 495             Trace("quant-engine-debug") << "...conflict!" << std::endl;
 496             break;
 497           }
 498         }
 499       }
 500       //flush all current lemmas
 501       flushLemmas();
 502       //if we have added one, stop
 503       if( d_hasAddedLemma ){
 504         break;
 505       }else{
 506         Assert( !d_conflict );
 507         if( quant_e==QEFFORT_CONFLICT ){
 508           if( e==Theory::EFFORT_FULL ){
 509             //increment if a last call happened, we are not strictly enforcing interleaving, or already were in phase
 510             if( d_ierCounterLastLc!=d_ierCounter_lc || !options::instWhenStrictInterleave() || d_ierCounter%d_inst_when_phase!=0 ){
 511               d_ierCounter = d_ierCounter + 1;
 512               d_ierCounterLastLc = d_ierCounter_lc;
 513               d_ierCounter_c = d_ierCounter_c.get() + 1;
 514             }
 515           }else if( e==Theory::EFFORT_LAST_CALL ){
 516             d_ierCounter_lc = d_ierCounter_lc + 1;
 517           }
 518         }else if( quant_e==QEFFORT_MODEL ){
 519           if( e==Theory::EFFORT_LAST_CALL ){
 520             if( !d_recorded_inst.empty() ){
 521               setIncomplete = true;
 522             }
 523             //if we have a chance not to set incomplete
 524             if( !setIncomplete ){
 525               setIncomplete = false;
 526               //check if we should set the incomplete flag
 527               for( unsigned i=0; i<qm.size(); i++ ){
 528                 if( !qm[i]->checkComplete() ){
 529                   Trace("quant-engine-debug") << "Set incomplete because " << qm[i]->identify().c_str() << " was incomplete." << std::endl;
 530                   setIncomplete = true;
 531                   break;
 532                 }
 533               }
 534             }
 535             //if setIncomplete = false, we will answer SAT, otherwise we will run at quant_e QEFFORT_LAST_CALL
 536             if( !setIncomplete ){
 537               break;
 538             }
 539           }
 540         }
 541       }
 542     }
 543     d_curr_effort_level = QEFFORT_NONE;
 544     Trace("quant-engine-debug") << "Done check modules that needed check." << std::endl;
 545     if( d_hasAddedLemma ){
 546       //debug information
 547       if( Trace.isOn("inst-per-quant-round") ){
 548         for( std::map< Node, int >::iterator it = d_temp_inst_debug.begin(); it != d_temp_inst_debug.end(); ++it ){
 549           Trace("inst-per-quant-round") << " * " << it->second << " for " << it->first << std::endl;
 550           d_temp_inst_debug[it->first] = 0;
 551         }
 552       }
 553     }
 554     if( Trace.isOn("quant-engine") ){
 555       double clSet2 = double(clock())/double(CLOCKS_PER_SEC);
 556       Trace("quant-engine") << "Finished quantifiers engine, total time = " << (clSet2-clSet);
 557       Trace("quant-engine") << ", added lemma = " << d_hasAddedLemma;
 558       Trace("quant-engine") << std::endl;
 559     }
 560
 561     Trace("quant-engine-debug2") << "Finished quantifiers engine check." << std::endl;
 562   }else{
 563     Trace("quant-engine-debug2") << "Quantifiers Engine does not need check." << std::endl;
 564   }
 565
 566   //SAT case
 567   if( e==Theory::EFFORT_LAST_CALL && !d_hasAddedLemma ){
 568     if( options::produceModels() ){
 569       if( usedModelBuilder ){
 570         Trace("quant-engine-debug") << "Build completed model..." << std::endl;
 571         d_builder->buildModel( d_model, true );
 572       }else if( !d_model->isModelSet() ){
 573         //use default model builder when no module built the model
 574         Trace("quant-engine-debug") << "Build the model..." << std::endl;
 575         d_te->getModelBuilder()->buildModel( d_model, true );
 576         Trace("quant-engine-debug") << "Done building the model." << std::endl;
 577       }
 578     }
 579     if( setIncomplete ){
 580       Trace("quant-engine") << "Set incomplete flag." << std::endl;
 581       getOutputChannel().setIncomplete();
 582     }
 583     //output debug stats
 584     if( Trace.isOn("inst-per-quant") ){
 585       for( std::map< Node, int >::iterator it = d_total_inst_debug.begin(); it != d_total_inst_debug.end(); ++it ){
 586         Trace("inst-per-quant") << " * " << it->second << " for " << it->first << std::endl;
 587       }
 588     }
 589   }
 590 }
 591
 592 void QuantifiersEngine::notifyCombineTheories() {
 593   //if allowing theory combination to happen at most once between instantiation rounds
 594   //d_ierCounter = 1;
 595   //d_ierCounterLastLc = -1;
 596 }
 597
 598 bool QuantifiersEngine::reduceQuantifier( Node q ) {
 599   BoolMap::const_iterator it = d_quants_red.find( q );
 600   if( it==d_quants_red.end() ){
 601     Node lem;
 602     std::map< Node, Node >::iterator itr = d_quants_red_lem.find( q );
 603     if( itr==d_quants_red_lem.end() ){
 604       if( d_alpha_equiv ){
 605         Trace("quant-engine-red") << "Alpha equivalence " << q << "?" << std::endl;
 606         //add equivalence with another quantified formula
 607         lem = d_alpha_equiv->reduceQuantifier( q );
 608         if( !lem.isNull() ){
 609           Trace("quant-engine-red") << "...alpha equivalence success." << std::endl;
 610           ++(d_statistics.d_red_alpha_equiv);
 611         }
 612       }
 613       d_quants_red_lem[q] = lem;
 614     }else{
 615       lem = itr->second;
 616     }
 617     if( !lem.isNull() ){
 618       getOutputChannel().lemma( lem );
 619     }
 620     d_quants_red[q] = !lem.isNull();
 621     return !lem.isNull();
 622   }else{
 623     return (*it).second;
 624   }
 625 }
 626
 627 bool QuantifiersEngine::registerQuantifier( Node f ){
 628   std::map< Node, bool >::iterator it = d_quants.find( f );
 629   if( it==d_quants.end() ){
 630     Trace("quant") << "QuantifiersEngine : Register quantifier ";
 631     Trace("quant") << " : " << f << std::endl;
 632     ++(d_statistics.d_num_quant);
 633     Assert( f.getKind()==FORALL );
 634
 635     //check whether we should apply a reduction
 636     if( reduceQuantifier( f ) ){
 637       d_quants[f] = false;
 638       return false;
 639     }else{
 640       //make instantiation constants for f
 641       d_term_db->makeInstantiationConstantsFor( f );
 642       d_term_db->computeAttributes( f );
 643       for( unsigned i=0; i<d_modules.size(); i++ ){
 644         Trace("quant-debug") << "pre-register with " << d_modules[i]->identify() << "..." << std::endl;
 645         d_modules[i]->preRegisterQuantifier( f );
 646       }
 647       QuantifiersModule * qm = getOwner( f );
 648       if( qm!=NULL ){
 649         Trace("quant") << "   Owner : " << qm->identify() << std::endl;
 650       }
 651       //register with quantifier relevance
 652       if( d_quant_rel ){
 653         d_quant_rel->registerQuantifier( f );
 654       }
 655       //register with each module
 656       for( unsigned i=0; i<d_modules.size(); i++ ){
 657         Trace("quant-debug") << "register with " << d_modules[i]->identify() << "..." << std::endl;
 658         d_modules[i]->registerQuantifier( f );
 659       }
 660       //TODO: remove this
 661       Node ceBody = d_term_db->getInstConstantBody( f );
 662       //also register it with the strong solver
 663       //if( options::finiteModelFind() ){
 664       //  ((uf::TheoryUF*)d_te->theoryOf( THEORY_UF ))->getStrongSolver()->registerQuantifier( f );
 665       //}
 666       d_quants[f] = true;
 667       return true;
 668     }
 669   }else{
 670     return (*it).second;
 671   }
 672 }
 673
 674 void QuantifiersEngine::registerPattern( std::vector<Node> & pattern) {
 675   for(std::vector<Node>::iterator p = pattern.begin(); p != pattern.end(); ++p){
 676     std::set< Node > added;
 677     getTermDatabase()->addTerm( *p, added );
 678   }
 679 }
 680
 681 void QuantifiersEngine::assertQuantifier( Node f, bool pol ){
 682   if( !pol ){
 683     //if not reduced
 684     if( !reduceQuantifier( f ) ){
 685       //do skolemization
 686       if( d_skolemized.find( f )==d_skolemized.end() ){
 687         Node body = d_term_db->getSkolemizedBody( f );
 688         NodeBuilder<> nb(kind::OR);
 689         nb << f << body.notNode();
 690         Node lem = nb;
 691         if( Trace.isOn("quantifiers-sk-debug") ){
 692           Node slem = Rewriter::rewrite( lem );
 693           Trace("quantifiers-sk-debug") << "Skolemize lemma : " << slem << std::endl;
 694         }
 695         getOutputChannel().lemma( lem, false, true );
 696         d_skolemized[f] = true;
 697       }
 698     }
 699   }else{
 700     //assert to modules TODO : also for !pol?
 701     //register the quantifier, assert it to each module
 702     if( registerQuantifier( f ) ){
 703       d_model->assertQuantifier( f );
 704       for( int i=0; i<(int)d_modules.size(); i++ ){
 705         d_modules[i]->assertNode( f );
 706       }
 707       addTermToDatabase( d_term_db->getInstConstantBody( f ), true );
 708     }
 709   }
 710 }
 711
 712 void QuantifiersEngine::propagate( Theory::Effort level ){
 713   CodeTimer codeTimer(d_statistics.d_time);
 714
 715   for( int i=0; i<(int)d_modules.size(); i++ ){
 716     d_modules[i]->propagate( level );
 717   }
 718 }
 719
 720 Node QuantifiersEngine::getNextDecisionRequest(){
 721   for( int i=0; i<(int)d_modules.size(); i++ ){
 722     Node n = d_modules[i]->getNextDecisionRequest();
 723     if( !n.isNull() ){
 724       return n;
 725     }
 726   }
 727   return Node::null();
 728 }
 729
 730 quantifiers::TermDbSygus* QuantifiersEngine::getTermDatabaseSygus() {
 731   return getTermDatabase()->getTermDatabaseSygus();
 732 }
 733
 734 void QuantifiersEngine::addTermToDatabase( Node n, bool withinQuant, bool withinInstClosure ){
 735   if( options::incrementalSolving() ){
 736     if( d_presolve_in.find( n )==d_presolve_in.end() ){
 737       d_presolve_in.insert( n );
 738       d_presolve_cache.push_back( n );
 739       d_presolve_cache_wq.push_back( withinQuant );
 740       d_presolve_cache_wic.push_back( withinInstClosure );
 741     }
 742   }
 743   //only wait if we are doing incremental solving
 744   if( !d_presolve || !options::incrementalSolving() ){
 745     std::set< Node > added;
 746     getTermDatabase()->addTerm( n, added, withinQuant, withinInstClosure );
 747     //maybe have triggered instantiations if we are doing eager instantiation
 748     if( options::eagerInstQuant() ){
 749       flushLemmas();
 750     }
 751     //added contains also the Node that just have been asserted in this branch
 752     if( d_quant_rel ){
 753       for( std::set< Node >::iterator i=added.begin(), end=added.end(); i!=end; i++ ){
 754         if( !withinQuant ){
 755           d_quant_rel->setRelevance( i->getOperator(), 0 );
 756         }
 757       }
 758     }
 759   }
 760 }
 761
 762 void QuantifiersEngine::eqNotifyNewClass(TNode t) {
 763   addTermToDatabase( t );
 764   if( d_eq_query->getEqualityInference() ){
 765     d_eq_query->getEqualityInference()->eqNotifyNewClass( t );
 766   }
 767 }
 768
 769 void QuantifiersEngine::eqNotifyPreMerge(TNode t1, TNode t2) {
 770   if( d_eq_query->getEqualityInference() ){
 771     d_eq_query->getEqualityInference()->eqNotifyMerge( t1, t2 );
 772   }
 773 }
 774
 775 void QuantifiersEngine::eqNotifyPostMerge(TNode t1, TNode t2) {
 776
 777 }
 778
 779 void QuantifiersEngine::eqNotifyDisequal(TNode t1, TNode t2, TNode reason) {
 780   //if( d_qcf ){
 781   //  d_qcf->assertDisequal( t1, t2 );
 782   //}
 783 }
 784
 785 void QuantifiersEngine::computeTermVector( Node f, InstMatch& m, std::vector< Node >& vars, std::vector< Node >& terms ){
 786   for( size_t i=0; i<f[0].getNumChildren(); i++ ){
 787     Node n = m.get( i );
 788     if( !n.isNull() ){
 789       vars.push_back( f[0][i] );
 790       terms.push_back( n );
 791     }
 792   }
 793 }
 794
 795
 796 bool QuantifiersEngine::recordInstantiationInternal( Node q, std::vector< Node >& terms, bool modEq, bool addedLem ) {
 797   if( !addedLem ){
 798     //record the instantiation for deletion later
 799     d_recorded_inst.push_back( std::pair< Node, std::vector< Node > >( q, terms ) );
 800   }
 801   if( options::incrementalSolving() ){
 802     Trace("inst-add-debug") << "Adding into context-dependent inst trie, modEq = " << modEq << std::endl;
 803     inst::CDInstMatchTrie* imt;
 804     std::map< Node, inst::CDInstMatchTrie* >::iterator it = d_c_inst_match_trie.find( q );
 805     if( it!=d_c_inst_match_trie.end() ){
 806       imt = it->second;
 807     }else{
 808       imt = new CDInstMatchTrie( getUserContext() );
 809       d_c_inst_match_trie[q] = imt;
 810     }
 811     return imt->addInstMatch( this, q, terms, getUserContext(), modEq );
 812   }else{
 813     Trace("inst-add-debug") << "Adding into inst trie" << std::endl;
 814     return d_inst_match_trie[q].addInstMatch( this, q, terms, modEq );
 815   }
 816 }
 817
 818 bool QuantifiersEngine::removeInstantiationInternal( Node q, std::vector< Node >& terms ) {
 819   if( options::incrementalSolving() ){
 820     std::map< Node, inst::CDInstMatchTrie* >::iterator it = d_c_inst_match_trie.find( q );
 821     if( it!=d_c_inst_match_trie.end() ){
 822       return it->second->removeInstMatch( this, q, terms );
 823     }else{
 824       return false;
 825     }
 826   }else{
 827     return d_inst_match_trie[q].removeInstMatch( this, q, terms );
 828   }
 829 }
 830
 831 void QuantifiersEngine::setInstantiationLevelAttr( Node n, Node qn, uint64_t level ){
 832   Trace("inst-level-debug2") << "IL : " << n << " " << qn << " " << level << std::endl;
 833   //if not from the vector of terms we instantiatied
 834   if( qn.getKind()!=BOUND_VARIABLE && n!=qn ){
 835     //if this is a new term, without an instantiation level
 836     if( !n.hasAttribute(InstLevelAttribute()) ){
 837       InstLevelAttribute ila;
 838       n.setAttribute(ila,level);
 839       Trace("inst-level-debug") << "Set instantiation level " << n << " to " << level << std::endl;
 840     }
 841     Assert( n.getNumChildren()==qn.getNumChildren() );
 842     for( unsigned i=0; i<n.getNumChildren(); i++ ){
 843       setInstantiationLevelAttr( n[i], qn[i], level );
 844     }
 845   }
 846 }
 847
 848 void QuantifiersEngine::setInstantiationLevelAttr( Node n, uint64_t level ){
 849   if( !n.hasAttribute(InstLevelAttribute()) ){
 850     InstLevelAttribute ila;
 851     n.setAttribute(ila,level);
 852     Trace("inst-level-debug") << "Set instantiation level " << n << " to " << level << std::endl;
 853   }
 854   for( unsigned i=0; i<n.getNumChildren(); i++ ){
 855     setInstantiationLevelAttr( n[i], level );
 856   }
 857 }
 858
 859 Node QuantifiersEngine::getSubstitute( Node n, std::vector< Node >& terms ){
 860   if( n.getKind()==INST_CONSTANT ){
 861     Debug("check-inst") << "Substitute inst constant : " << n << std::endl;
 862     return terms[n.getAttribute(InstVarNumAttribute())];
 863   }else{
 864     //if( !quantifiers::TermDb::hasInstConstAttr( n ) ){
 865       //Debug("check-inst") << "No inst const attr : " << n << std::endl;
 866       //return n;
 867     //}else{
 868       //Debug("check-inst") << "Recurse on : " << n << std::endl;
 869     std::vector< Node > cc;
 870     if( n.getMetaKind() == kind::metakind::PARAMETERIZED ){
 871       cc.push_back( n.getOperator() );
 872     }
 873     bool changed = false;
 874     for( unsigned i=0; i<n.getNumChildren(); i++ ){
 875       Node c = getSubstitute( n[i], terms );
 876       cc.push_back( c );
 877       changed = changed || c!=n[i];
 878     }
 879     if( changed ){
 880       Node ret = NodeManager::currentNM()->mkNode( n.getKind(), cc );
 881       return ret;
 882     }else{
 883       return n;
 884     }
 885   }
 886 }
 887
 888
 889 Node QuantifiersEngine::getInstantiation( Node q, std::vector< Node >& vars, std::vector< Node >& terms, bool doVts ){
 890   Node body;
 891   Assert( vars.size()==terms.size() );
 892   //process partial instantiation if necessary
 893   if( q[0].getNumChildren()!=vars.size() ){
 894     body = q[ 1 ].substitute( vars.begin(), vars.end(), terms.begin(), terms.end() );
 895     std::vector< Node > uninst_vars;
 896     //doing a partial instantiation, must add quantifier for all uninstantiated variables
 897     for( unsigned i=0; i<q[0].getNumChildren(); i++ ){
 898       if( std::find( vars.begin(), vars.end(), q[0][i] )==vars.end() ){
 899         uninst_vars.push_back( q[0][i] );
 900       }
 901     }
 902     Trace("partial-inst") << "Partially instantiating with " << vars.size() << " / " << q[0].getNumChildren() << " for " << q << std::endl;
 903     Assert( !uninst_vars.empty() );
 904     Node bvl = NodeManager::currentNM()->mkNode( BOUND_VAR_LIST, uninst_vars );
 905     body = NodeManager::currentNM()->mkNode( FORALL, bvl, body );
 906     Trace("partial-inst") << "Partial instantiation : " << q << std::endl;
 907     Trace("partial-inst") << "                      : " << body << std::endl;
 908   }else{
 909     if( options::cbqi() ){
 910       body = q[ 1 ].substitute( vars.begin(), vars.end(), terms.begin(), terms.end() );
 911     }else{
 912       //do optimized version
 913       Node icb = d_term_db->getInstConstantBody( q );
 914       body = getSubstitute( icb, terms );
 915       if( Debug.isOn("check-inst") ){
 916         Node body2 = q[ 1 ].substitute( vars.begin(), vars.end(), terms.begin(), terms.end() );
 917         if( body!=body2 ){
 918           Debug("check-inst") << "Substitution is wrong : " << body << " " << body2 << std::endl;
 919         }
 920       }
 921     }
 922   }
 923   if( doVts ){
 924     //do virtual term substitution
 925     body = Rewriter::rewrite( body );
 926     Trace("quant-vts-debug") << "Rewrite vts symbols in " << body << std::endl;
 927     Node body_r = d_term_db->rewriteVtsSymbols( body );
 928     Trace("quant-vts-debug") << "            ...result: " << body_r << std::endl;
 929     body = body_r;
 930   }
 931   return body;
 932 }
 933
 934 Node QuantifiersEngine::getInstantiation( Node q, InstMatch& m, bool doVts ){
 935   std::vector< Node > vars;
 936   std::vector< Node > terms;
 937   computeTermVector( q, m, vars, terms );
 938   return getInstantiation( q, vars, terms, doVts );
 939 }
 940
 941 Node QuantifiersEngine::getInstantiation( Node q, std::vector< Node >& terms, bool doVts ) {
 942   Assert( d_term_db->d_vars.find( q )!=d_term_db->d_vars.end() );
 943   return getInstantiation( q, d_term_db->d_vars[q], terms, doVts );
 944 }
 945
 946 /*
 947 bool QuantifiersEngine::existsInstantiation( Node f, InstMatch& m, bool modEq ){
 948   if( options::incrementalSolving() ){
 949     if( d_c_inst_match_trie.find( f )!=d_c_inst_match_trie.end() ){
 950       if( d_c_inst_match_trie[f]->existsInstMatch( this, f, m, getUserContext(), modEq ) ){
 951         return true;
 952       }
 953     }
 954   }else{
 955     if( d_inst_match_trie.find( f )!=d_inst_match_trie.end() ){
 956       if( d_inst_match_trie[f].existsInstMatch( this, f, m, modEq ) ){
 957         return true;
 958       }
 959     }
 960   }
 961   return false;
 962 }
 963 */
 964
 965 bool QuantifiersEngine::addLemma( Node lem, bool doCache, bool doRewrite ){
 966   if( doCache ){
 967     if( doRewrite ){
 968       lem = Rewriter::rewrite(lem);
 969     }
 970     Trace("inst-add-debug") << "Adding lemma : " << lem << std::endl;
 971     BoolMap::const_iterator itp = d_lemmas_produced_c.find( lem );
 972     if( itp==d_lemmas_produced_c.end() || !(*itp).second ){
 973       //d_curr_out->lemma( lem, false, true );
 974       d_lemmas_produced_c[ lem ] = true;
 975       d_lemmas_waiting.push_back( lem );
 976       Trace("inst-add-debug") << "Added lemma" << std::endl;
 977       return true;
 978     }else{
 979       Trace("inst-add-debug") << "Duplicate." << std::endl;
 980       return false;
 981     }
 982   }else{
 983     //do not need to rewrite, will be rewritten after sending
 984     d_lemmas_waiting.push_back( lem );
 985     return true;
 986   }
 987 }
 988
 989 bool QuantifiersEngine::removeLemma( Node lem ) {
 990   std::vector< Node >::iterator it = std::find( d_lemmas_waiting.begin(), d_lemmas_waiting.end(), lem );
 991   if( it!=d_lemmas_waiting.end() ){
 992     d_lemmas_waiting.erase( it, it + 1 );
 993     d_lemmas_produced_c[ lem ] = false;
 994     return true;
 995   }else{
 996     return false;
 997   }
 998 }
 999
1000 void QuantifiersEngine::addRequirePhase( Node lit, bool req ){
1001   d_phase_req_waiting[lit] = req;
1002 }
1003
1004 bool QuantifiersEngine::addInstantiation( Node q, InstMatch& m, bool mkRep, bool modEq, bool doVts ){
1005   std::vector< Node > terms;
1006   m.getTerms( q, terms );
1007   return addInstantiation( q, terms, mkRep, modEq, doVts );
1008 }
1009
1010 bool QuantifiersEngine::addInstantiation( Node q, std::vector< Node >& terms, bool mkRep, bool modEq, bool doVts ) {
1011   // For resource-limiting (also does a time check).
1012   getOutputChannel().safePoint(options::quantifierStep());
1013   Assert( !d_conflict );
1014   Assert( terms.size()==q[0].getNumChildren() );
1015   Trace("inst-add-debug") << "For quantified formula " << q << ", add instantiation: " << std::endl;
1016   std::vector< Node > rlv_cond;
1017   for( unsigned i=0; i<terms.size(); i++ ){
1018     Trace("inst-add-debug") << "  " << q[0][i];
1019     Trace("inst-add-debug2") << " -> " << terms[i];
1020     if( terms[i].isNull() ){
1021       terms[i] = d_term_db->getModelBasisTerm( q[0][i].getType() );
1022     }
1023     if( mkRep ){
1024       //pick the best possible representative for instantiation, based on past use and simplicity of term
1025       terms[i] = d_eq_query->getInternalRepresentative( terms[i], q, i );
1026     }else{
1027       //ensure the type is correct
1028       terms[i] = quantifiers::TermDb::ensureType( terms[i], q[0][i].getType() );
1029     }
1030     Trace("inst-add-debug") << " -> " << terms[i] << std::endl;
1031     if( terms[i].isNull() ){
1032       Trace("inst-add-debug") << " --> Failed to make term vector, due to term/type restrictions." << std::endl;
1033       return false;
1034     }else{
1035       //get relevancy conditions
1036       if( options::instRelevantCond() ){
1037         quantifiers::TermDb::getRelevancyCondition( terms[i], rlv_cond );
1038       }
1039     }
1040 #ifdef CVC4_ASSERTIONS
1041     bool bad_inst = false;
1042     if( quantifiers::TermDb::containsUninterpretedConstant( terms[i] ) ){
1043       bad_inst = true;
1044     }else if( !terms[i].getType().isSubtypeOf( q[0][i].getType() ) ){
1045       bad_inst = true;
1046     }else if( options::cbqi() ){
1047       Node icf = quantifiers::TermDb::getInstConstAttr(terms[i]);
1048       if( !icf.isNull() ){
1049         if( icf==q ){
1050           bad_inst = true;
1051         }else{
1052           bad_inst = quantifiers::TermDb::containsTerms( terms[i], d_term_db->d_inst_constants[q] );
1053         }
1054       }
1055     }
1056     //this assertion is critical to soundness
1057     if( bad_inst ){
1058       Trace("inst")<< "***& Bad Instantiate " << q << " with " << std::endl;
1059       for( unsigned j=0; j<terms.size(); j++ ){
1060         Trace("inst") << "   " << terms[j] << std::endl;
1061       }
1062       Assert( false );
1063     }
1064 #endif
1065   }
1066
1067   //check based on instantiation level
1068   if( options::instMaxLevel()!=-1 || options::lteRestrictInstClosure() ){
1069     for( unsigned i=0; i<terms.size(); i++ ){
1070       if( !d_term_db->isTermEligibleForInstantiation( terms[i], q, true ) ){
1071         return false;
1072       }
1073     }
1074   }
1075
1076   //check for positive entailment
1077   if( options::instNoEntail() ){
1078     //TODO: check consistency of equality engine (if not aborting on utility's reset)
1079     std::map< TNode, TNode > subs;
1080     for( unsigned i=0; i<terms.size(); i++ ){
1081       subs[q[0][i]] = terms[i];
1082     }
1083     if( d_term_db->isEntailed( q[1], subs, false, true ) ){
1084       Trace("inst-add-debug") << " --> Currently entailed." << std::endl;
1085       return false;
1086     }
1087     //Node eval = d_term_db->evaluateTerm( q[1], subs, false, true );
1088     //Trace("ajr-temp") << "Instantiation evaluates to : " << std::endl;
1089     //Trace("ajr-temp") << "   " << eval << std::endl;
1090   }
1091
1092   //check for term vector duplication
1093   bool alreadyExists = !recordInstantiationInternal( q, terms, modEq );
1094   if( alreadyExists ){
1095     Trace("inst-add-debug") << " --> Already exists." << std::endl;
1096     ++(d_statistics.d_inst_duplicate_eq);
1097     return false;
1098   }
1099
1100   //construct the instantiation
1101   Trace("inst-add-debug") << "Constructing instantiation..." << std::endl;
1102   Assert( d_term_db->d_vars[q].size()==terms.size() );
1103   Node body = getInstantiation( q, d_term_db->d_vars[q], terms, doVts );  //do virtual term substitution
1104   Node orig_body = body;
1105   body = quantifiers::QuantifiersRewriter::preprocess( body, true );
1106   Trace("inst-debug") << "...preprocess to " << body << std::endl;
1107
1108   //construct the lemma
1109   Trace("inst-assert") << "(assert " << body << ")" << std::endl;
1110   body = Rewriter::rewrite(body);
1111   Node lem;
1112   if( rlv_cond.empty() ){
1113     lem = NodeManager::currentNM()->mkNode( kind::OR, q.negate(), body );
1114   }else{
1115     rlv_cond.push_back( q.negate() );
1116     rlv_cond.push_back( body );
1117     lem = NodeManager::currentNM()->mkNode( kind::OR, rlv_cond );
1118   }
1119   lem = Rewriter::rewrite(lem);
1120
1121   //check for lemma duplication
1122   if( addLemma( lem, true, false ) ){
1123     d_total_inst_debug[q]++;
1124     d_temp_inst_debug[q]++;
1125     d_total_inst_count_debug++;
1126     if( Trace.isOn("inst") ){
1127       Trace("inst") << "*** Instantiate " << q << " with " << std::endl;
1128       for( unsigned i=0; i<terms.size(); i++ ){
1129         if( Trace.isOn("inst") ){
1130           Trace("inst") << "   " << terms[i];
1131           if( Trace.isOn("inst-debug") ){
1132             Trace("inst-debug") << ", type=" << terms[i].getType() << ", var_type=" << q[0][i].getType();
1133           }
1134           Trace("inst") << std::endl;
1135         }
1136       }
1137     }
1138     if( options::instMaxLevel()!=-1 ){
1139       if( doVts ){
1140         //virtual term substitution/instantiation level features are incompatible
1141         Assert( false );
1142       }else{
1143         uint64_t maxInstLevel = 0;
1144         for( unsigned i=0; i<terms.size(); i++ ){
1145           if( terms[i].hasAttribute(InstLevelAttribute()) ){
1146             if( terms[i].getAttribute(InstLevelAttribute())>maxInstLevel ){
1147               maxInstLevel = terms[i].getAttribute(InstLevelAttribute());
1148             }
1149           }
1150         }
1151         setInstantiationLevelAttr( orig_body, q[1], maxInstLevel+1 );
1152       }
1153     }
1154     if( d_curr_effort_level>QEFFORT_CONFLICT && d_curr_effort_level<QEFFORT_NONE ){
1155       //notify listeners
1156       for( unsigned j=0; j<d_inst_notify.size(); j++ ){
1157         if( !d_inst_notify[j]->notifyInstantiation( d_curr_effort_level, q, lem, terms, body ) ){
1158           Trace("inst-add-debug") << "...we are in conflict." << std::endl;
1159           d_conflict = true;
1160           d_conflict_c = true;
1161           Assert( !d_lemmas_waiting.empty() );
1162           break;
1163         }
1164       }
1165     }
1166     Trace("inst-add-debug") << " --> Success." << std::endl;
1167     ++(d_statistics.d_instantiations);
1168     return true;
1169   }else{
1170     Trace("inst-add-debug") << " --> Lemma already exists." << std::endl;
1171     ++(d_statistics.d_inst_duplicate);
1172     return false;
1173   }
1174 }
1175
1176 bool QuantifiersEngine::removeInstantiation( Node q, Node lem, std::vector< Node >& terms ) {
1177   //lem must occur in d_waiting_lemmas
1178   if( removeLemma( lem ) ){
1179     return removeInstantiationInternal( q, terms );
1180   }else{
1181     return false;
1182   }
1183 }
1184
1185 bool QuantifiersEngine::addSplit( Node n, bool reqPhase, bool reqPhasePol ){
1186   n = Rewriter::rewrite( n );
1187   Node lem = NodeManager::currentNM()->mkNode( OR, n, n.notNode() );
1188   if( addLemma( lem ) ){
1189     Debug("inst") << "*** Add split " << n<< std::endl;
1190     return true;
1191   }
1192   return false;
1193 }
1194
1195 bool QuantifiersEngine::addSplitEquality( Node n1, Node n2, bool reqPhase, bool reqPhasePol ){
1196   //Assert( !areEqual( n1, n2 ) );
1197   //Assert( !areDisequal( n1, n2 ) );
1198   Kind knd = n1.getType()==NodeManager::currentNM()->booleanType() ? IFF : EQUAL;
1199   Node fm = NodeManager::currentNM()->mkNode( knd, n1, n2 );
1200   return addSplit( fm );
1201 }
1202
1203 void QuantifiersEngine::markRelevant( Node q ) {
1204   d_model->markRelevant( q );
1205 }
1206
1207 bool QuantifiersEngine::getInstWhenNeedsCheck( Theory::Effort e ) {
1208   Trace("quant-engine-debug2") << "Get inst when needs check, counts=" << d_ierCounter << ", " << d_ierCounter_lc << std::endl;
1209   //determine if we should perform check, based on instWhenMode
1210   bool performCheck = false;
1211   if( options::instWhenMode()==quantifiers::INST_WHEN_FULL ){
1212     performCheck = ( e >= Theory::EFFORT_FULL );
1213   }else if( options::instWhenMode()==quantifiers::INST_WHEN_FULL_DELAY ){
1214     performCheck = ( e >= Theory::EFFORT_FULL ) && !getTheoryEngine()->needCheck();
1215   }else if( options::instWhenMode()==quantifiers::INST_WHEN_FULL_LAST_CALL ){
1216     performCheck = ( ( e==Theory::EFFORT_FULL && d_ierCounter%d_inst_when_phase!=0 ) || e==Theory::EFFORT_LAST_CALL );
1217   }else if( options::instWhenMode()==quantifiers::INST_WHEN_FULL_DELAY_LAST_CALL ){
1218     performCheck = ( ( e==Theory::EFFORT_FULL && !getTheoryEngine()->needCheck() && d_ierCounter%d_inst_when_phase!=0 ) || e==Theory::EFFORT_LAST_CALL );
1219   }else if( options::instWhenMode()==quantifiers::INST_WHEN_LAST_CALL ){
1220     performCheck = ( e >= Theory::EFFORT_LAST_CALL );
1221   }else{
1222     performCheck = true;
1223   }
1224   if( e==Theory::EFFORT_LAST_CALL ){
1225     //with bounded integers, skip every other last call,
1226     // since matching loops may occur with infinite quantification
1227     if( d_ierCounter_lc%2==0 && options::fmfBoundInt() ){
1228       performCheck = false;
1229     }
1230   }
1231   return performCheck;
1232 }
1233
1234 quantifiers::UserPatMode QuantifiersEngine::getInstUserPatMode() {
1235   if( options::userPatternsQuant()==quantifiers::USER_PAT_MODE_INTERLEAVE ){
1236     return d_ierCounter%2==0 ? quantifiers::USER_PAT_MODE_USE : quantifiers::USER_PAT_MODE_RESORT;
1237   }else{
1238     return options::userPatternsQuant();
1239   }
1240 }
1241
1242 void QuantifiersEngine::flushLemmas(){
1243   if( !d_lemmas_waiting.empty() ){
1244     //filter based on notify classes
1245     if( !d_inst_notify.empty() ){
1246       unsigned prev_lem_sz = d_lemmas_waiting.size();
1247       for( unsigned j=0; j<d_inst_notify.size(); j++ ){
1248         d_inst_notify[j]->filterInstantiations();
1249       }
1250       if( prev_lem_sz!=d_lemmas_waiting.size() ){
1251         Trace("quant-engine") << "...filtered instances : " << d_lemmas_waiting.size() << " / " << prev_lem_sz << std::endl;
1252       }
1253     }
1254     //take default output channel if none is provided
1255     d_hasAddedLemma = true;
1256     for( unsigned i=0; i<d_lemmas_waiting.size(); i++ ){
1257       Trace("qe-lemma") << "Lemma : " << d_lemmas_waiting[i] << std::endl;
1258       getOutputChannel().lemma( d_lemmas_waiting[i], false, true );
1259     }
1260     d_lemmas_waiting.clear();
1261   }
1262   if( !d_phase_req_waiting.empty() ){
1263     for( std::map< Node, bool >::iterator it = d_phase_req_waiting.begin(); it != d_phase_req_waiting.end(); ++it ){
1264       Trace("qe-lemma") << "Require phase : " << it->first << " -> " << it->second << std::endl;
1265       getOutputChannel().requirePhase( it->first, it->second );
1266     }
1267     d_phase_req_waiting.clear();
1268   }
1269 }
1270
1271 void QuantifiersEngine::printInstantiations( std::ostream& out ) {
1272   bool printed = false;
1273   for( BoolMap::iterator it = d_skolemized.begin(); it != d_skolemized.end(); ++it ){
1274     Node q = (*it).first;
1275     printed = true;
1276     out << "Skolem constants of " << q << " : " << std::endl;
1277     out << "  ( ";
1278     for( unsigned i=0; i<d_term_db->d_skolem_constants[q].size(); i++ ){
1279       if( i>0 ){ out << ", "; }
1280       out << d_term_db->d_skolem_constants[q][i];
1281     }
1282     out << " )" << std::endl;
1283     out << std::endl;
1284   }
1285   if( options::incrementalSolving() ){
1286     for( std::map< Node, inst::CDInstMatchTrie* >::iterator it = d_c_inst_match_trie.begin(); it != d_c_inst_match_trie.end(); ++it ){
1287       printed = true;
1288       out << "Instantiations of " << it->first << " : " << std::endl;
1289       it->second->print( out, it->first );
1290     }
1291   }else{
1292     for( std::map< Node, inst::InstMatchTrie >::iterator it = d_inst_match_trie.begin(); it != d_inst_match_trie.end(); ++it ){
1293       printed = true;
1294       out << "Instantiations of " << it->first << " : " << std::endl;
1295       it->second.print( out, it->first );
1296       out << std::endl;
1297     }
1298   }
1299   if( !printed ){
1300     out << "No instantiations." << std::endl;
1301   }
1302 }
1303
1304 void QuantifiersEngine::printSynthSolution( std::ostream& out ) {
1305   if( d_ceg_inst ){
1306     d_ceg_inst->printSynthSolution( out );
1307   }else{
1308     out << "Internal error : module for synth solution not found." << std::endl;
1309   }
1310 }
1311
1312 void QuantifiersEngine::getInstantiations( std::map< Node, std::vector< Node > >& insts ) {
1313   if( options::incrementalSolving() ){
1314     for( std::map< Node, inst::CDInstMatchTrie* >::iterator it = d_c_inst_match_trie.begin(); it != d_c_inst_match_trie.end(); ++it ){
1315       it->second->getInstantiations( insts[it->first], it->first, this );
1316     }
1317   }else{
1318     for( std::map< Node, inst::InstMatchTrie >::iterator it = d_inst_match_trie.begin(); it != d_inst_match_trie.end(); ++it ){
1319       it->second.getInstantiations( insts[it->first], it->first, this );
1320     }
1321   }
1322 }
1323
1324 QuantifiersEngine::Statistics::Statistics()
1325     : d_time("theory::QuantifiersEngine::time"),
1326       d_num_quant("QuantifiersEngine::Num_Quantifiers", 0),
1327       d_instantiation_rounds("QuantifiersEngine::Rounds_Instantiation_Full", 0),
1328       d_instantiation_rounds_lc("QuantifiersEngine::Rounds_Instantiation_Last_Call", 0),
1329       d_instantiations("QuantifiersEngine::Instantiations_Total", 0),
1330       d_inst_duplicate("QuantifiersEngine::Duplicate_Inst", 0),
1331       d_inst_duplicate_eq("QuantifiersEngine::Duplicate_Inst_Eq", 0),
1332       d_triggers("QuantifiersEngine::Triggers", 0),
1333       d_simple_triggers("QuantifiersEngine::Triggers_Simple", 0),
1334       d_multi_triggers("QuantifiersEngine::Triggers_Multi", 0),
1335       d_multi_trigger_instantiations("QuantifiersEngine::Multi_Trigger_Instantiations", 0),
1336       d_red_alpha_equiv("QuantifiersEngine::Reductions_Alpha_Equivalence", 0),
1337       d_red_lte_partial_inst("QuantifiersEngine::Reductions_Lte_Partial_Inst", 0),
1338       d_instantiations_user_patterns("QuantifiersEngine::Instantiations_User_Patterns", 0),
1339       d_instantiations_auto_gen("QuantifiersEngine::Instantiations_Auto_Gen", 0),
1340       d_instantiations_guess("QuantifiersEngine::Instantiations_Guess", 0),
1341       d_instantiations_cbqi_arith("QuantifiersEngine::Instantiations_Cbqi_Arith", 0)
1342 {
1343   smtStatisticsRegistry()->registerStat(&d_time);
1344   smtStatisticsRegistry()->registerStat(&d_num_quant);
1345   smtStatisticsRegistry()->registerStat(&d_instantiation_rounds);
1346   smtStatisticsRegistry()->registerStat(&d_instantiation_rounds_lc);
1347   smtStatisticsRegistry()->registerStat(&d_instantiations);
1348   smtStatisticsRegistry()->registerStat(&d_inst_duplicate);
1349   smtStatisticsRegistry()->registerStat(&d_inst_duplicate_eq);
1350   smtStatisticsRegistry()->registerStat(&d_triggers);
1351   smtStatisticsRegistry()->registerStat(&d_simple_triggers);
1352   smtStatisticsRegistry()->registerStat(&d_multi_triggers);
1353   smtStatisticsRegistry()->registerStat(&d_multi_trigger_instantiations);
1354   smtStatisticsRegistry()->registerStat(&d_red_alpha_equiv);
1355   smtStatisticsRegistry()->registerStat(&d_red_lte_partial_inst);
1356   smtStatisticsRegistry()->registerStat(&d_instantiations_user_patterns);
1357   smtStatisticsRegistry()->registerStat(&d_instantiations_auto_gen);
1358   smtStatisticsRegistry()->registerStat(&d_instantiations_guess);
1359   smtStatisticsRegistry()->registerStat(&d_instantiations_cbqi_arith);
1360 }
1361
1362 QuantifiersEngine::Statistics::~Statistics(){
1363   smtStatisticsRegistry()->unregisterStat(&d_time);
1364   smtStatisticsRegistry()->unregisterStat(&d_num_quant);
1365   smtStatisticsRegistry()->unregisterStat(&d_instantiation_rounds);
1366   smtStatisticsRegistry()->unregisterStat(&d_instantiation_rounds_lc);
1367   smtStatisticsRegistry()->unregisterStat(&d_instantiations);
1368   smtStatisticsRegistry()->unregisterStat(&d_inst_duplicate);
1369   smtStatisticsRegistry()->unregisterStat(&d_inst_duplicate_eq);
1370   smtStatisticsRegistry()->unregisterStat(&d_triggers);
1371   smtStatisticsRegistry()->unregisterStat(&d_simple_triggers);
1372   smtStatisticsRegistry()->unregisterStat(&d_multi_triggers);
1373   smtStatisticsRegistry()->unregisterStat(&d_multi_trigger_instantiations);
1374   smtStatisticsRegistry()->unregisterStat(&d_red_alpha_equiv);
1375   smtStatisticsRegistry()->unregisterStat(&d_red_lte_partial_inst);
1376   smtStatisticsRegistry()->unregisterStat(&d_instantiations_user_patterns);
1377   smtStatisticsRegistry()->unregisterStat(&d_instantiations_auto_gen);
1378   smtStatisticsRegistry()->unregisterStat(&d_instantiations_guess);
1379   smtStatisticsRegistry()->unregisterStat(&d_instantiations_cbqi_arith);
1380 }
1381
1382 eq::EqualityEngine* QuantifiersEngine::getMasterEqualityEngine(){
1383   return getTheoryEngine()->getMasterEqualityEngine();
1384 }
1385
1386 void QuantifiersEngine::debugPrintEqualityEngine( const char * c ) {
1387   eq::EqualityEngine* ee = getMasterEqualityEngine();
1388   eq::EqClassesIterator eqcs_i = eq::EqClassesIterator( ee );
1389   std::map< TypeNode, int > typ_num;
1390   while( !eqcs_i.isFinished() ){
1391     TNode r = (*eqcs_i);
1392     TypeNode tr = r.getType();
1393     if( typ_num.find( tr )==typ_num.end() ){
1394       typ_num[tr] = 0;
1395     }
1396     typ_num[tr]++;
1397     bool firstTime = true;
1398     Trace(c) << "  " << r;
1399     Trace(c) << " : { ";
1400     eq::EqClassIterator eqc_i = eq::EqClassIterator( r, ee );
1401     while( !eqc_i.isFinished() ){
1402       TNode n = (*eqc_i);
1403       if( r!=n ){
1404         if( firstTime ){
1405           Trace(c) << std::endl;
1406           firstTime = false;
1407         }
1408         Trace(c) << "    " << n << std::endl;
1409       }
1410       ++eqc_i;
1411     }
1412     if( !firstTime ){ Trace(c) << "  "; }
1413     Trace(c) << "}" << std::endl;
1414     ++eqcs_i;
1415   }
1416   Trace(c) << std::endl;
1417   for( std::map< TypeNode, int >::iterator it = typ_num.begin(); it != typ_num.end(); ++it ){
1418     Trace(c) << "# eqc for " << it->first << " : " << it->second << std::endl;
1419   }
1420 }
1421
1422
1423 EqualityQueryQuantifiersEngine::EqualityQueryQuantifiersEngine( context::Context* c, QuantifiersEngine* qe ) : d_qe( qe ), d_eqi_counter( c ), d_reset_count( 0 ){
1424   if( options::inferArithTriggerEq() ){
1425     d_eq_inference = new quantifiers::EqualityInference( c, options::inferArithTriggerEqExp() );
1426   }else{
1427     d_eq_inference = NULL;
1428   }
1429 }
1430
1431 EqualityQueryQuantifiersEngine::~EqualityQueryQuantifiersEngine(){
1432   delete d_eq_inference;
1433 }
1434
1435 bool EqualityQueryQuantifiersEngine::reset( Theory::Effort e ){
1436   d_int_rep.clear();
1437   d_reset_count++;
1438   return processInferences( e );
1439 }
1440
1441 bool EqualityQueryQuantifiersEngine::processInferences( Theory::Effort e ) {
1442   if( options::inferArithTriggerEq() ){
1443     eq::EqualityEngine* ee = getEngine();
1444     //updated implementation
1445     while( d_eqi_counter.get()<d_eq_inference->getNumPendingMerges() ){
1446       Node eq = d_eq_inference->getPendingMerge( d_eqi_counter.get() );
1447       Node eq_exp = d_eq_inference->getPendingMergeExplanation( d_eqi_counter.get() );
1448       Trace("quant-engine-ee-proc") << "processInferences : Infer : " << eq << std::endl;
1449       Trace("quant-engine-ee-proc") << "      explanation : " << eq_exp << std::endl;
1450       Assert( ee->hasTerm( eq[0] ) );
1451       Assert( ee->hasTerm( eq[1] ) );
1452       if( areDisequal( eq[0], eq[1] ) ){
1453         Trace("quant-engine-ee-proc") << "processInferences : Conflict : " << eq << std::endl;
1454         if( Trace.isOn("term-db-lemma") ){
1455           Trace("term-db-lemma") << "Disequal terms, equal by normalization : " << eq[0] << " " << eq[1] << "!!!!" << std::endl;
1456           if( !d_qe->getTheoryEngine()->needCheck() ){
1457             Trace("term-db-lemma") << "  all theories passed with no lemmas." << std::endl;
1458             //this should really never happen (implies arithmetic is incomplete when sharing is enabled)
1459             Assert( false );
1460           }
1461           Trace("term-db-lemma") << "  add split on : " << eq << std::endl;
1462         }
1463         d_qe->addSplit( eq );
1464         return false;
1465       }else{
1466         ee->assertEquality( eq, true, eq_exp );
1467         d_eqi_counter = d_eqi_counter.get() + 1;
1468       }
1469     }
1470     Assert( ee->consistent() );
1471   }
1472   return true;
1473 }
1474
1475 bool EqualityQueryQuantifiersEngine::hasTerm( Node a ){
1476   return getEngine()->hasTerm( a );
1477 }
1478
1479 Node EqualityQueryQuantifiersEngine::getRepresentative( Node a ){
1480   eq::EqualityEngine* ee = getEngine();
1481   if( ee->hasTerm( a ) ){
1482     return ee->getRepresentative( a );
1483   }else{
1484     return a;
1485   }
1486 }
1487
1488 bool EqualityQueryQuantifiersEngine::areEqual( Node a, Node b ){
1489   if( a==b ){
1490     return true;
1491   }else{
1492     eq::EqualityEngine* ee = getEngine();
1493     if( ee->hasTerm( a ) && ee->hasTerm( b ) ){
1494       return ee->areEqual( a, b );
1495     }else{
1496       return false;
1497     }
1498   }
1499 }
1500
1501 bool EqualityQueryQuantifiersEngine::areDisequal( Node a, Node b ){
1502   if( a==b ){
1503     return false;
1504   }else{
1505     eq::EqualityEngine* ee = getEngine();
1506     if( ee->hasTerm( a ) && ee->hasTerm( b ) ){
1507       return ee->areDisequal( a, b, false );
1508     }else{
1509       return a.isConst() && b.isConst();
1510     }
1511   }
1512 }
1513
1514 Node EqualityQueryQuantifiersEngine::getInternalRepresentative( Node a, Node f, int index ){
1515   Assert( f.isNull() || f.getKind()==FORALL );
1516   Node r = getRepresentative( a );
1517   if( options::finiteModelFind() ){
1518     if( r.isConst() && quantifiers::TermDb::containsUninterpretedConstant( r ) ){
1519       //map back from values assigned by model, if any
1520       if( d_qe->getModel() ){
1521         std::map< Node, Node >::iterator it = d_qe->getModel()->d_rep_set.d_values_to_terms.find( r );
1522         if( it!=d_qe->getModel()->d_rep_set.d_values_to_terms.end() ){
1523           r = it->second;
1524           r = getRepresentative( r );
1525         }else{
1526           if( r.getType().isSort() ){
1527             Trace("internal-rep-warn") << "No representative for UF constant." << std::endl;
1528             //should never happen : UF constants should never escape model
1529             Assert( false );
1530           }
1531         }
1532       }
1533     }
1534   }
1535   if( options::quantRepMode()==quantifiers::QUANT_REP_MODE_EE ){
1536     return r;
1537   }else{
1538     TypeNode v_tn = f.isNull() ? a.getType() : f[0][index].getType();
1539     std::map< Node, Node >::iterator itir = d_int_rep[v_tn].find( r );
1540     if( itir==d_int_rep[v_tn].end() ){
1541       //find best selection for representative
1542       Node r_best;
1543       //if( options::fmfRelevantDomain() && !f.isNull() ){
1544       //  Trace("internal-rep-debug") << "Consult relevant domain to mkRep " << r << std::endl;
1545       //  r_best = d_qe->getRelevantDomain()->getRelevantTerm( f, index, r );
1546       //  Trace("internal-rep-debug") << "Returned " << r_best << " " << r << std::endl;
1547       //}
1548       std::vector< Node > eqc;
1549       getEquivalenceClass( r, eqc );
1550       Trace("internal-rep-select") << "Choose representative for equivalence class : { ";
1551       for( unsigned i=0; i<eqc.size(); i++ ){
1552         if( i>0 ) Trace("internal-rep-select") << ", ";
1553         Trace("internal-rep-select") << eqc[i];
1554       }
1555       Trace("internal-rep-select")  << " }, type = " << v_tn << std::endl;
1556       int r_best_score = -1;
1557       for( size_t i=0; i<eqc.size(); i++ ){
1558         int score = getRepScore( eqc[i], f, index, v_tn );
1559         if( score!=-2 ){
1560           if( r_best.isNull() || ( score>=0 && ( r_best_score<0 || score<r_best_score ) ) ){
1561             r_best = eqc[i];
1562             r_best_score = score;
1563           }
1564         }
1565       }
1566       if( r_best.isNull() ){
1567         Trace("internal-rep-warn") << "No valid choice for representative in eqc class." << std::endl;
1568         r_best = r;
1569       }
1570       //now, make sure that no other member of the class is an instance
1571       std::hash_map<TNode, Node, TNodeHashFunction> cache;
1572       r_best = getInstance( r_best, eqc, cache );
1573       //store that this representative was chosen at this point
1574       if( d_rep_score.find( r_best )==d_rep_score.end() ){
1575         d_rep_score[ r_best ] = d_reset_count;
1576       }
1577       Trace("internal-rep-select") << "...Choose " << r_best << " with score " << r_best_score << std::endl;
1578       Assert( r_best.getType().isSubtypeOf( v_tn ) );
1579       d_int_rep[v_tn][r] = r_best;
1580       if( r_best!=a ){
1581         Trace("internal-rep-debug") << "rep( " << a << " ) = " << r << ", " << std::endl;
1582         Trace("internal-rep-debug") << "int_rep( " << a << " ) = " << r_best << ", " << std::endl;
1583       }
1584       return r_best;
1585     }else{
1586       return itir->second;
1587     }
1588   }
1589 }
1590
1591 void EqualityQueryQuantifiersEngine::flattenRepresentatives( std::map< TypeNode, std::vector< Node > >& reps ) {
1592   //make sure internal representatives currently exist
1593   for( std::map< TypeNode, std::vector< Node > >::iterator it = reps.begin(); it != reps.end(); ++it ){
1594     if( it->first.isSort() ){
1595       for( unsigned i=0; i<it->second.size(); i++ ){
1596         Node r = getInternalRepresentative( it->second[i], Node::null(), 0 );
1597       }
1598     }
1599   }
1600   Trace("internal-rep-flatten") << "---Flattening representatives : " << std::endl;
1601   for( std::map< TypeNode, std::map< Node, Node > >::iterator itt = d_int_rep.begin(); itt != d_int_rep.end(); ++itt ){
1602     for( std::map< Node, Node >::iterator it = itt->second.begin(); it != itt->second.end(); ++it ){
1603       Trace("internal-rep-flatten") << itt->first << " : irep( " << it->first << " ) = " << it->second << std::endl;
1604     }
1605   }
1606   //store representatives for newly created terms
1607   std::map< Node, Node > temp_rep_map;
1608
1609   bool success;
1610   do {
1611     success = false;
1612     for( std::map< TypeNode, std::map< Node, Node > >::iterator itt = d_int_rep.begin(); itt != d_int_rep.end(); ++itt ){
1613       for( std::map< Node, Node >::iterator it = itt->second.begin(); it != itt->second.end(); ++it ){
1614         if( it->second.getKind()==APPLY_UF && it->second.getType().isSort() ){
1615           Node ni = it->second;
1616           std::vector< Node > cc;
1617           cc.push_back( it->second.getOperator() );
1618           bool changed = false;
1619           for( unsigned j=0; j<ni.getNumChildren(); j++ ){
1620             if( ni[j].getType().isSort() ){
1621               Node r = getRepresentative( ni[j] );
1622               if( itt->second.find( r )==itt->second.end() ){
1623                 Assert( temp_rep_map.find( r )!=temp_rep_map.end() );
1624                 r = temp_rep_map[r];
1625               }
1626               if( r==ni ){
1627                 //found sub-term as instance
1628                 Trace("internal-rep-flatten-debug") << "...Changed " << it->second << " to subterm " << ni[j] << std::endl;
1629                 itt->second[it->first] = ni[j];
1630                 changed = false;
1631                 success = true;
1632                 break;
1633               }else{
1634                 Node ir = itt->second[r];
1635                 cc.push_back( ir );
1636                 if( ni[j]!=ir ){
1637                   changed = true;
1638                 }
1639               }
1640             }else{
1641               changed = false;
1642               break;
1643             }
1644           }
1645           if( changed ){
1646             Node n = NodeManager::currentNM()->mkNode( APPLY_UF, cc );
1647             Trace("internal-rep-flatten-debug") << "...Changed " << it->second << " to " << n << std::endl;
1648             success = true;
1649             itt->second[it->first] = n;
1650             temp_rep_map[n] = it->first;
1651           }
1652         }
1653       }
1654     }
1655   }while( success );
1656   Trace("internal-rep-flatten") << "---After flattening : " << std::endl;
1657   for( std::map< TypeNode, std::map< Node, Node > >::iterator itt = d_int_rep.begin(); itt != d_int_rep.end(); ++itt ){
1658     for( std::map< Node, Node >::iterator it = itt->second.begin(); it != itt->second.end(); ++it ){
1659       Trace("internal-rep-flatten") << itt->first << " : irep( " << it->first << " ) = " << it->second << std::endl;
1660     }
1661   }
1662 }
1663
1664 eq::EqualityEngine* EqualityQueryQuantifiersEngine::getEngine(){
1665   return d_qe->getMasterEqualityEngine();
1666 }
1667
1668 void EqualityQueryQuantifiersEngine::getEquivalenceClass( Node a, std::vector< Node >& eqc ){
1669   eq::EqualityEngine* ee = getEngine();
1670   if( ee->hasTerm( a ) ){
1671     Node rep = ee->getRepresentative( a );
1672     eq::EqClassIterator eqc_iter( rep, ee );
1673     while( !eqc_iter.isFinished() ){
1674       eqc.push_back( *eqc_iter );
1675       eqc_iter++;
1676     }
1677   }else{
1678     eqc.push_back( a );
1679   }
1680   //a should be in its equivalence class
1681   Assert( std::find( eqc.begin(), eqc.end(), a )!=eqc.end() );
1682 }
1683
1684 TNode EqualityQueryQuantifiersEngine::getCongruentTerm( Node f, std::vector< TNode >& args ) {
1685   return d_qe->getTermDatabase()->getCongruentTerm( f, args );
1686 }
1687
1688 //helper functions
1689
1690 Node EqualityQueryQuantifiersEngine::getInstance( Node n, const std::vector< Node >& eqc, std::hash_map<TNode, Node, TNodeHashFunction>& cache ){
1691   if(cache.find(n) != cache.end()) {
1692     return cache[n];
1693   }
1694   for( size_t i=0; i<n.getNumChildren(); i++ ){
1695     Node nn = getInstance( n[i], eqc, cache );
1696     if( !nn.isNull() ){
1697       return cache[n] = nn;
1698     }
1699   }
1700   if( std::find( eqc.begin(), eqc.end(), n )!=eqc.end() ){
1701     return cache[n] = n;
1702   }else{
1703     return cache[n] = Node::null();
1704   }
1705 }
1706
1707 //-2 : invalid, -1 : undesired, otherwise : smaller the score, the better
1708 int EqualityQueryQuantifiersEngine::getRepScore( Node n, Node f, int index, TypeNode v_tn ){
1709   if( options::cbqi() && quantifiers::TermDb::hasInstConstAttr(n) ){  //reject
1710     return -2;
1711   }else if( !n.getType().isSubtypeOf( v_tn ) ){  //reject if incorrect type
1712     return -2;
1713   }else if( options::lteRestrictInstClosure() && ( !d_qe->getTermDatabase()->isInstClosure( n ) || !d_qe->getTermDatabase()->hasTermCurrent( n, false ) ) ){
1714     return -1;
1715   }else if( options::instMaxLevel()!=-1 ){
1716     //score prefer lowest instantiation level
1717     if( n.hasAttribute(InstLevelAttribute()) ){
1718       return n.getAttribute(InstLevelAttribute());
1719     }else{
1720       return options::instLevelInputOnly() ? -1 : 0;
1721     }
1722   }else{
1723     if( options::quantRepMode()==quantifiers::QUANT_REP_MODE_FIRST ){
1724       //score prefers earliest use of this term as a representative
1725       return d_rep_score.find( n )==d_rep_score.end() ? -1 : d_rep_score[n];
1726     }else{
1727       Assert( options::quantRepMode()==quantifiers::QUANT_REP_MODE_DEPTH );
1728       return quantifiers::TermDb::getTermDepth( n );
1729     }
1730   }
1731 }