src/theory/quantifiers_engine.h

   1 /*********************                                                        */
   2 /*! \file quantifiers_engine.h
   3  ** \verbatim
   4  ** Top contributors (to current version):
   5  **   Andrew Reynolds, Morgan Deters, Tim King
   6  ** This file is part of the CVC4 project.
   7  ** Copyright (c) 2009-2017 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 Theory instantiator, Instantiation Engine classes
  13  **/
  14
  15 #include "cvc4_private.h"
  16
  17 #ifndef __CVC4__THEORY__QUANTIFIERS_ENGINE_H
  18 #define __CVC4__THEORY__QUANTIFIERS_ENGINE_H
  19
  20 #include <iostream>
  21 #include <map>
  22 #include <memory>
  23 #include <unordered_map>
  24
  25 #include "context/cdhashset.h"
  26 #include "context/cdlist.h"
  27 #include "expr/attribute.h"
  28 #include "options/quantifiers_modes.h"
  29 #include "theory/quantifiers/inst_match.h"
  30 #include "theory/quantifiers/quant_util.h"
  31 #include "theory/theory.h"
  32 #include "util/hash.h"
  33 #include "util/statistics_registry.h"
  34
  35 namespace CVC4 {
  36
  37 class TheoryEngine;
  38
  39 namespace theory {
  40
  41 class QuantifiersEngine;
  42
  43 namespace quantifiers {
  44   //TODO: organize this more/review this, github issue #1163
  45   //TODO: include these instead of doing forward declarations? #1307
  46   //utilities
  47   class TermDb;
  48   class TermDbSygus;
  49   class TermUtil;
  50   class Instantiate;
  51   class Skolemize;
  52   class TermEnumeration;
  53   class FirstOrderModel;
  54   class QuantAttributes;
  55   class QuantEPR;
  56   class QuantRelevance;
  57   class RelevantDomain;
  58   class BvInverter;
  59   class InstPropagator;
  60   class EqualityInference;
  61   class EqualityQueryQuantifiersEngine;
  62   //modules, these are "subsolvers" of the quantifiers theory.
  63   class InstantiationEngine;
  64   class ModelEngine;
  65   class BoundedIntegers;
  66   class QuantConflictFind;
  67   class RewriteEngine;
  68   class QModelBuilder;
  69   class ConjectureGenerator;
  70   class CegInstantiation;
  71   class LtePartialInst;
  72   class AlphaEquivalence;
  73   class InstStrategyEnum;
  74   class InstStrategyCbqi;
  75   class InstStrategyCegqi;
  76   class QuantDSplit;
  77   class QuantAntiSkolem;
  78   class EqualityInference;
  79 }/* CVC4::theory::quantifiers */
  80
  81 namespace inst {
  82   class TriggerTrie;
  83 }/* CVC4::theory::inst */
  84
  85
  86 class QuantifiersEngine {
  87   // TODO: remove these github issue #1163
  88   friend class quantifiers::InstantiationEngine;
  89   friend class quantifiers::InstStrategyCbqi;
  90   friend class quantifiers::InstStrategyCegqi;
  91   friend class quantifiers::ModelEngine;
  92   friend class quantifiers::RewriteEngine;
  93   friend class quantifiers::QuantConflictFind;
  94   friend class inst::InstMatch;
  95   typedef context::CDHashMap< Node, bool, NodeHashFunction > BoolMap;
  96   typedef context::CDList<Node> NodeList;
  97   typedef context::CDList<bool> BoolList;
  98   typedef context::CDHashSet<Node, NodeHashFunction> NodeSet;
  99 private:
 100   /** reference to theory engine object */
 101   TheoryEngine* d_te;
 102   /** vector of utilities for quantifiers */
 103   std::vector< QuantifiersUtil* > d_util;
 104   /** vector of modules for quantifiers */
 105   std::vector< QuantifiersModule* > d_modules;
 106   /** equality query class */
 107   quantifiers::EqualityQueryQuantifiersEngine* d_eq_query;
 108   /** equality inference class */
 109   quantifiers::EqualityInference* d_eq_inference;
 110   /** for computing relevance of quantifiers */
 111   quantifiers::QuantRelevance* d_quant_rel;
 112   /** relevant domain */
 113   quantifiers::RelevantDomain* d_rel_dom;
 114   /** inversion utility for BV instantiation */
 115   quantifiers::BvInverter * d_bv_invert;
 116   /** alpha equivalence */
 117   quantifiers::AlphaEquivalence * d_alpha_equiv;
 118   /** model builder */
 119   quantifiers::QModelBuilder* d_builder;
 120   /** utility for effectively propositional logic */
 121   quantifiers::QuantEPR* d_qepr;
 122   /** term database */
 123   quantifiers::TermDb* d_term_db;
 124   /** sygus term database */
 125   quantifiers::TermDbSygus* d_sygus_tdb;
 126   /** term utilities */
 127   quantifiers::TermUtil* d_term_util;
 128   /** quantifiers attributes */
 129   std::unique_ptr<quantifiers::QuantAttributes> d_quant_attr;
 130   /** instantiate utility */
 131   std::unique_ptr<quantifiers::Instantiate> d_instantiate;
 132   /** skolemize utility */
 133   std::unique_ptr<quantifiers::Skolemize> d_skolemize;
 134   /** term enumeration utility */
 135   std::unique_ptr<quantifiers::TermEnumeration> d_term_enum;
 136   /** instantiation engine */
 137   quantifiers::InstantiationEngine* d_inst_engine;
 138   /** model engine */
 139   quantifiers::ModelEngine* d_model_engine;
 140   /** bounded integers utility */
 141   quantifiers::BoundedIntegers * d_bint;
 142   /** Conflict find mechanism for quantifiers */
 143   quantifiers::QuantConflictFind* d_qcf;
 144   /** rewrite rules utility */
 145   quantifiers::RewriteEngine * d_rr_engine;
 146   /** subgoal generator */
 147   quantifiers::ConjectureGenerator * d_sg_gen;
 148   /** ceg instantiation */
 149   quantifiers::CegInstantiation * d_ceg_inst;
 150   /** lte partial instantiation */
 151   quantifiers::LtePartialInst * d_lte_part_inst;
 152   /** full saturation */
 153   quantifiers::InstStrategyEnum* d_fs;
 154   /** counterexample-based quantifier instantiation */
 155   quantifiers::InstStrategyCbqi * d_i_cbqi;
 156   /** quantifiers splitting */
 157   quantifiers::QuantDSplit * d_qsplit;
 158   /** quantifiers anti-skolemization */
 159   quantifiers::QuantAntiSkolem * d_anti_skolem;
 160   /** quantifiers instantiation propagtor */
 161   quantifiers::InstPropagator * d_inst_prop;
 162
 163  private:  //this information is reset during check
 164     /** current effort level */
 165   QuantifiersModule::QEffort d_curr_effort_level;
 166   /** are we in conflict */
 167   bool d_conflict;
 168   context::CDO<bool> d_conflict_c;
 169   /** has added lemma this round */
 170   bool d_hasAddedLemma;
 171   /** whether to use model equality engine */
 172   bool d_useModelEe;
 173  private:
 174   /** list of all quantifiers seen */
 175   std::map< Node, bool > d_quants;
 176   /** quantifiers reduced */
 177   BoolMap d_quants_red;
 178   std::map< Node, Node > d_quants_red_lem;
 179   /** list of all lemmas produced */
 180   //std::map< Node, bool > d_lemmas_produced;
 181   BoolMap d_lemmas_produced_c;
 182   /** lemmas waiting */
 183   std::vector< Node > d_lemmas_waiting;
 184   /** phase requirements waiting */
 185   std::map< Node, bool > d_phase_req_waiting;
 186   /** all triggers will be stored in this trie */
 187   inst::TriggerTrie* d_tr_trie;
 188   /** extended model object */
 189   quantifiers::FirstOrderModel* d_model;
 190   /** inst round counters TODO: make context-dependent? */
 191   context::CDO< int > d_ierCounter_c;
 192   int d_ierCounter;
 193   int d_ierCounter_lc;
 194   int d_ierCounterLastLc;
 195   int d_inst_when_phase;
 196   /** has presolve been called */
 197   context::CDO< bool > d_presolve;
 198   /** presolve cache */
 199   NodeSet d_presolve_in;
 200   NodeList d_presolve_cache;
 201   BoolList d_presolve_cache_wq;
 202   BoolList d_presolve_cache_wic;
 203
 204 public:
 205   QuantifiersEngine(context::Context* c, context::UserContext* u, TheoryEngine* te);
 206   ~QuantifiersEngine();
 207   /** get theory engine */
 208   TheoryEngine* getTheoryEngine() { return d_te; }
 209   /** get equality query */
 210   EqualityQuery* getEqualityQuery();
 211   /** get the equality inference */
 212   quantifiers::EqualityInference* getEqualityInference() { return d_eq_inference; }
 213   /** get default sat context for quantifiers engine */
 214   context::Context* getSatContext();
 215   /** get default sat context for quantifiers engine */
 216   context::UserContext* getUserContext();
 217   /** get default output channel for the quantifiers engine */
 218   OutputChannel& getOutputChannel();
 219   /** get default valuation for the quantifiers engine */
 220   Valuation& getValuation();
 221   /** get the logic info for the quantifiers engine */
 222   const LogicInfo& getLogicInfo() const;
 223   /** get relevant domain */
 224   quantifiers::RelevantDomain* getRelevantDomain() { return d_rel_dom; }
 225   /** get the BV inverter utility */
 226   quantifiers::BvInverter * getBvInverter() { return d_bv_invert; }
 227   /** get quantifier relevance */
 228   quantifiers::QuantRelevance* getQuantifierRelevance() { return d_quant_rel; }
 229   /** get the model builder */
 230   quantifiers::QModelBuilder* getModelBuilder() { return d_builder; }
 231   /** get utility for EPR */
 232   quantifiers::QuantEPR* getQuantEPR() { return d_qepr; }
 233  public:  // modules
 234   /** get instantiation engine */
 235   quantifiers::InstantiationEngine* getInstantiationEngine() { return d_inst_engine; }
 236   /** get model engine */
 237   quantifiers::ModelEngine* getModelEngine() { return d_model_engine; }
 238   /** get bounded integers utility */
 239   quantifiers::BoundedIntegers * getBoundedIntegers() { return d_bint; }
 240   /** Conflict find mechanism for quantifiers */
 241   quantifiers::QuantConflictFind* getConflictFind() { return d_qcf; }
 242   /** rewrite rules utility */
 243   quantifiers::RewriteEngine * getRewriteEngine() { return d_rr_engine; }
 244   /** subgoal generator */
 245   quantifiers::ConjectureGenerator * getConjectureGenerator() { return d_sg_gen; }
 246   /** ceg instantiation */
 247   quantifiers::CegInstantiation * getCegInstantiation() { return d_ceg_inst; }
 248   /** local theory ext partial inst */
 249   quantifiers::LtePartialInst * getLtePartialInst() { return d_lte_part_inst; }
 250   /** get full saturation */
 251   quantifiers::InstStrategyEnum* getInstStrategyEnum() { return d_fs; }
 252   /** get inst strategy cbqi */
 253   quantifiers::InstStrategyCbqi * getInstStrategyCbqi() { return d_i_cbqi; }
 254   /** get quantifiers splitting */
 255   quantifiers::QuantDSplit * getQuantDSplit() { return d_qsplit; }
 256   /** get quantifiers anti-skolemization */
 257   quantifiers::QuantAntiSkolem * getQuantAntiSkolem() { return d_anti_skolem; }
 258 private:
 259   /** owner of quantified formulas */
 260   std::map< Node, QuantifiersModule * > d_owner;
 261   std::map< Node, int > d_owner_priority;
 262 public:
 263   /** get owner */
 264   QuantifiersModule * getOwner( Node q );
 265   /** set owner */
 266   void setOwner( Node q, QuantifiersModule * m, int priority = 0 );
 267   /** considers */
 268   bool hasOwnership( Node q, QuantifiersModule * m = NULL );
 269   /** is finite bound */
 270   bool isFiniteBound( Node q, Node v );
 271 public:
 272   /** presolve */
 273   void presolve();
 274   /** notify preprocessed assertion */
 275   void ppNotifyAssertions(const std::vector<Node>& assertions);
 276   /** check at level */
 277   void check( Theory::Effort e );
 278   /** notify that theories were combined */
 279   void notifyCombineTheories();
 280   /** register quantifier */
 281   bool registerQuantifier( Node f );
 282   /** register quantifier */
 283   void registerPattern( std::vector<Node> & pattern);
 284   /** assert universal quantifier */
 285   void assertQuantifier( Node q, bool pol );
 286   /** propagate */
 287   void propagate( Theory::Effort level );
 288   /** get next decision request */
 289   Node getNextDecisionRequest( unsigned& priority );
 290 private:
 291   /** reduceQuantifier, return true if reduced */
 292   bool reduceQuantifier( Node q );
 293   /** flush lemmas */
 294   void flushLemmas();
 295 public:
 296   /** add lemma lem */
 297   bool addLemma( Node lem, bool doCache = true, bool doRewrite = true );
 298   /** remove pending lemma */
 299   bool removeLemma( Node lem );
 300   /** add require phase */
 301   void addRequirePhase( Node lit, bool req );
 302   /** split on node n */
 303   bool addSplit( Node n, bool reqPhase = false, bool reqPhasePol = true );
 304   /** add split equality */
 305   bool addSplitEquality( Node n1, Node n2, bool reqPhase = false, bool reqPhasePol = true );
 306   /** add EPR axiom */
 307   bool addEPRAxiom( TypeNode tn );
 308   /** mark relevant quantified formula, this will indicate it should be checked before the others */
 309   void markRelevant( Node q );
 310   /** has added lemma */
 311   bool hasAddedLemma() { return !d_lemmas_waiting.empty() || d_hasAddedLemma; }
 312   /** is in conflict */
 313   bool inConflict() { return d_conflict; }
 314   /** set conflict */
 315   void setConflict();
 316   /** get current q effort */
 317   QuantifiersModule::QEffort getCurrentQEffort() { return d_curr_effort_level; }
 318   /** get number of waiting lemmas */
 319   unsigned getNumLemmasWaiting() { return d_lemmas_waiting.size(); }
 320   /** get needs check */
 321   bool getInstWhenNeedsCheck( Theory::Effort e );
 322   /** get user pat mode */
 323   quantifiers::UserPatMode getInstUserPatMode();
 324 public:
 325   /** get model */
 326   quantifiers::FirstOrderModel* getModel() { return d_model; }
 327   /** get term database */
 328   quantifiers::TermDb* getTermDatabase() { return d_term_db; }
 329   /** get term database sygus */
 330   quantifiers::TermDbSygus * getTermDatabaseSygus() { return d_sygus_tdb; }
 331   /** get term utilities */
 332   quantifiers::TermUtil* getTermUtil() { return d_term_util; }
 333   /** get quantifiers attributes */
 334   quantifiers::QuantAttributes* getQuantAttributes() {
 335     return d_quant_attr.get();
 336   }
 337   /** get instantiate utility */
 338   quantifiers::Instantiate* getInstantiate() { return d_instantiate.get(); }
 339   /** get skolemize utility */
 340   quantifiers::Skolemize* getSkolemize() { return d_skolemize.get(); }
 341   /** get term enumeration utility */
 342   quantifiers::TermEnumeration* getTermEnumeration()
 343   {
 344     return d_term_enum.get();
 345   }
 346   /** get trigger database */
 347   inst::TriggerTrie* getTriggerDatabase() { return d_tr_trie; }
 348   /** add term to database */
 349   void addTermToDatabase( Node n, bool withinQuant = false, bool withinInstClosure = false );
 350   /** notification when master equality engine is updated */
 351   void eqNotifyNewClass(TNode t);
 352   void eqNotifyPreMerge(TNode t1, TNode t2);
 353   void eqNotifyPostMerge(TNode t1, TNode t2);
 354   void eqNotifyDisequal(TNode t1, TNode t2, TNode reason);
 355   /** get the master equality engine */
 356   eq::EqualityEngine* getMasterEqualityEngine();
 357   /** get the active equality engine */
 358   eq::EqualityEngine* getActiveEqualityEngine();
 359   /** use model equality engine */
 360   bool usingModelEqualityEngine() const { return d_useModelEe; }
 361   /** debug print equality engine */
 362   void debugPrintEqualityEngine( const char * c );
 363   /** get internal representative */
 364   Node getInternalRepresentative( Node a, Node q, int index );
 365
 366  public:
 367   //----------user interface for instantiations (see quantifiers/instantiate.h)
 368   /** print instantiations */
 369   void printInstantiations(std::ostream& out);
 370   /** print solution for synthesis conjectures */
 371   void printSynthSolution(std::ostream& out);
 372   /** get list of quantified formulas that were instantiated */
 373   void getInstantiatedQuantifiedFormulas(std::vector<Node>& qs);
 374   /** get instantiations */
 375   void getInstantiations(Node q, std::vector<Node>& insts);
 376   void getInstantiations(std::map<Node, std::vector<Node> >& insts);
 377   /** get instantiation term vectors */
 378   void getInstantiationTermVectors(Node q,
 379                                    std::vector<std::vector<Node> >& tvecs);
 380   void getInstantiationTermVectors(
 381       std::map<Node, std::vector<std::vector<Node> > >& insts);
 382   /** get instantiated conjunction */
 383   Node getInstantiatedConjunction(Node q);
 384   /** get unsat core lemmas */
 385   bool getUnsatCoreLemmas(std::vector<Node>& active_lemmas);
 386   bool getUnsatCoreLemmas(std::vector<Node>& active_lemmas,
 387                           std::map<Node, Node>& weak_imp);
 388   /** get explanation for instantiation lemmas */
 389   void getExplanationForInstLemmas(const std::vector<Node>& lems,
 390                                    std::map<Node, Node>& quant,
 391                                    std::map<Node, std::vector<Node> >& tvec);
 392
 393   /** get synth solutions
 394    *
 395    * This function adds entries to sol_map that map functions-to-synthesize with
 396    * their solutions, for all active conjectures. This should be called
 397    * immediately after the solver answers unsat for sygus input.
 398    *
 399    * For details on what is added to sol_map, see
 400    * CegConjecture::getSynthSolutions.
 401    */
 402   void getSynthSolutions(std::map<Node, Node>& sol_map);
 403
 404   //----------end user interface for instantiations
 405
 406   /** statistics class */
 407   class Statistics {
 408   public:
 409     TimerStat d_time;
 410     TimerStat d_qcf_time;
 411     TimerStat d_ematching_time;
 412     IntStat d_num_quant;
 413     IntStat d_instantiation_rounds;
 414     IntStat d_instantiation_rounds_lc;
 415     IntStat d_triggers;
 416     IntStat d_simple_triggers;
 417     IntStat d_multi_triggers;
 418     IntStat d_multi_trigger_instantiations;
 419     IntStat d_red_alpha_equiv;
 420     IntStat d_instantiations_user_patterns;
 421     IntStat d_instantiations_auto_gen;
 422     IntStat d_instantiations_guess;
 423     IntStat d_instantiations_qcf;
 424     IntStat d_instantiations_qcf_prop;
 425     IntStat d_instantiations_fmf_exh;
 426     IntStat d_instantiations_fmf_mbqi;
 427     IntStat d_instantiations_cbqi;
 428     IntStat d_instantiations_rr;
 429     Statistics();
 430     ~Statistics();
 431   };/* class QuantifiersEngine::Statistics */
 432   Statistics d_statistics;
 433 };/* class QuantifiersEngine */
 434
 435 }/* CVC4::theory namespace */
 436 }/* CVC4 namespace */
 437
 438 #endif /* __CVC4__THEORY__QUANTIFIERS_ENGINE_H */