src/theory/theory_engine.h

   1 /*********************                                                        */
   2 /*! \file theory_engine.h
   3  ** \verbatim
   4  ** Top contributors (to current version):
   5  **   Dejan Jovanovic, Andrew Reynolds, Morgan Deters
   6  ** This file is part of the CVC4 project.
   7  ** Copyright (c) 2009-2020 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 The theory engine
  13  **
  14  ** The theory engine.
  15  **/
  16
  17 #include "cvc4_private.h"
  18
  19 #ifndef CVC4__THEORY_ENGINE_H
  20 #define CVC4__THEORY_ENGINE_H
  21
  22 #include <deque>
  23 #include <memory>
  24 #include <set>
  25 #include <unordered_map>
  26 #include <utility>
  27 #include <vector>
  28
  29 #include "base/check.h"
  30 #include "context/cdhashset.h"
  31 #include "expr/node.h"
  32 #include "options/options.h"
  33 #include "options/smt_options.h"
  34 #include "options/theory_options.h"
  35 #include "prop/prop_engine.h"
  36 #include "smt/command.h"
  37 #include "theory/atom_requests.h"
  38 #include "theory/engine_output_channel.h"
  39 #include "theory/interrupted.h"
  40 #include "theory/rewriter.h"
  41 #include "theory/sort_inference.h"
  42 #include "theory/substitutions.h"
  43 #include "theory/term_registration_visitor.h"
  44 #include "theory/theory.h"
  45 #include "theory/theory_preprocessor.h"
  46 #include "theory/uf/equality_engine.h"
  47 #include "theory/valuation.h"
  48 #include "util/hash.h"
  49 #include "util/resource_manager.h"
  50 #include "util/statistics_registry.h"
  51 #include "util/unsafe_interrupt_exception.h"
  52
  53 namespace CVC4 {
  54
  55 class ResourceManager;
  56 class LemmaProofRecipe;
  57
  58 /**
  59  * A pair of a theory and a node. This is used to mark the flow of
  60  * propagations between theories.
  61  */
  62 struct NodeTheoryPair {
  63   Node d_node;
  64   theory::TheoryId d_theory;
  65   size_t d_timestamp;
  66   NodeTheoryPair(TNode n, theory::TheoryId t, size_t ts = 0)
  67       : d_node(n), d_theory(t), d_timestamp(ts)
  68   {
  69   }
  70   NodeTheoryPair() : d_theory(theory::THEORY_LAST), d_timestamp() {}
  71   // Comparison doesn't take into account the timestamp
  72   bool operator == (const NodeTheoryPair& pair) const {
  73     return d_node == pair.d_node && d_theory == pair.d_theory;
  74   }
  75 };/* struct NodeTheoryPair */
  76
  77 struct NodeTheoryPairHashFunction {
  78   NodeHashFunction hashFunction;
  79   // Hash doesn't take into account the timestamp
  80   size_t operator()(const NodeTheoryPair& pair) const {
  81     uint64_t hash = fnv1a::fnv1a_64(NodeHashFunction()(pair.d_node));
  82     return static_cast<size_t>(fnv1a::fnv1a_64(pair.d_theory, hash));
  83   }
  84 };/* struct NodeTheoryPairHashFunction */
  85
  86
  87 /* Forward declarations */
  88 namespace theory {
  89 class TheoryModel;
  90 class CombinationEngine;
  91 class DecisionManager;
  92 class RelevanceManager;
  93
  94 namespace eq {
  95 class EqualityEngine;
  96 }  // namespace eq
  97
  98 namespace quantifiers {
  99 class TermDb;
 100 }
 101
 102 class EntailmentCheckParameters;
 103 class EntailmentCheckSideEffects;
 104 }/* CVC4::theory namespace */
 105
 106 class RemoveTermFormulas;
 107
 108 /**
 109  * This is essentially an abstraction for a collection of theories.  A
 110  * TheoryEngine provides services to a PropEngine, making various
 111  * T-solvers look like a single unit to the propositional part of
 112  * CVC4.
 113  */
 114 class TheoryEngine {
 115
 116   /** Shared terms database can use the internals notify the theories */
 117   friend class SharedTermsDatabase;
 118   friend class theory::CombinationEngine;
 119   friend class theory::quantifiers::TermDb;
 120   friend class theory::EngineOutputChannel;
 121   friend class theory::CombinationEngine;
 122
 123   /** Associated PropEngine engine */
 124   prop::PropEngine* d_propEngine;
 125
 126   /** Our context */
 127   context::Context* d_context;
 128
 129   /** Our user context */
 130   context::UserContext* d_userContext;
 131
 132   /**
 133    * A table of from theory IDs to theory pointers. Never use this table
 134    * directly, use theoryOf() instead.
 135    */
 136   theory::Theory* d_theoryTable[theory::THEORY_LAST];
 137
 138   /**
 139    * A collection of theories that are "active" for the current run.
 140    * This set is provided by the user (as a logic string, say, in SMT-LIBv2
 141    * format input), or else by default it's all-inclusive.  This is important
 142    * because we can optimize for single-theory runs (no sharing), can reduce
 143    * the cost of walking the DAG on registration, etc.
 144    */
 145   const LogicInfo& d_logicInfo;
 146
 147   //--------------------------------- new proofs
 148   /** Proof node manager used by this theory engine, if proofs are enabled */
 149   ProofNodeManager* d_pnm;
 150   //--------------------------------- end new proofs
 151
 152   /**
 153    * The database of shared terms.
 154    */
 155   SharedTermsDatabase d_sharedTerms;
 156
 157   /** The combination manager we are using */
 158   std::unique_ptr<theory::CombinationEngine> d_tc;
 159   /**
 160    * The quantifiers engine
 161    */
 162   theory::QuantifiersEngine* d_quantEngine;
 163   /**
 164    * The decision manager
 165    */
 166   std::unique_ptr<theory::DecisionManager> d_decManager;
 167   /** The relevance manager */
 168   std::unique_ptr<theory::RelevanceManager> d_relManager;
 169
 170   /** Default visitor for pre-registration */
 171   PreRegisterVisitor d_preRegistrationVisitor;
 172
 173   /** Visitor for collecting shared terms */
 174   SharedTermsVisitor d_sharedTermsVisitor;
 175
 176   /** are we in eager model building mode? (see setEagerModelBuilding). */
 177   bool d_eager_model_building;
 178
 179   typedef std::unordered_map<Node, Node, NodeHashFunction> NodeMap;
 180   typedef std::unordered_map<TNode, Node, TNodeHashFunction> TNodeMap;
 181
 182   /**
 183    * Used for "missed-t-propagations" dumping mode only.  A set of all
 184    * theory-propagable literals.
 185    */
 186   context::CDList<TNode> d_possiblePropagations;
 187
 188   /**
 189    * Used for "missed-t-propagations" dumping mode only.  A
 190    * context-dependent set of those theory-propagable literals that
 191    * have been propagated.
 192    */
 193   context::CDHashSet<Node, NodeHashFunction> d_hasPropagated;
 194
 195   /**
 196    * Output channels for individual theories.
 197    */
 198   theory::EngineOutputChannel* d_theoryOut[theory::THEORY_LAST];
 199
 200   /**
 201    * Are we in conflict.
 202    */
 203   context::CDO<bool> d_inConflict;
 204
 205   /**
 206    * Are we in "SAT mode"? In this state, the user can query for the model.
 207    * This corresponds to the state in Figure 4.1, page 52 of the SMT-LIB
 208    * standard, version 2.6.
 209    */
 210   bool d_inSatMode;
 211
 212   /**
 213    * Called by the theories to notify of a conflict.
 214    */
 215   void conflict(TNode conflict, theory::TheoryId theoryId);
 216
 217   /**
 218    * Debugging flag to ensure that shutdown() is called before the
 219    * destructor.
 220    */
 221   bool d_hasShutDown;
 222
 223   /**
 224    * True if a theory has notified us of incompleteness (at this
 225    * context level or below).
 226    */
 227   context::CDO<bool> d_incomplete;
 228
 229   /**
 230    * Called by the theories to notify that the current branch is incomplete.
 231    */
 232   void setIncomplete(theory::TheoryId theory) {
 233     d_incomplete = true;
 234   }
 235
 236   /**
 237    * Mapping of propagations from recievers to senders.
 238    */
 239   typedef context::CDHashMap<NodeTheoryPair, NodeTheoryPair, NodeTheoryPairHashFunction> PropagationMap;
 240   PropagationMap d_propagationMap;
 241
 242   /**
 243    * Timestamp of propagations
 244    */
 245   context::CDO<size_t> d_propagationMapTimestamp;
 246
 247   /**
 248    * Literals that are propagated by the theory. Note that these are TNodes.
 249    * The theory can only propagate nodes that have an assigned literal in the
 250    * SAT solver and are hence referenced in the SAT solver.
 251    */
 252   context::CDList<TNode> d_propagatedLiterals;
 253
 254   /**
 255    * The index of the next literal to be propagated by a theory.
 256    */
 257   context::CDO<unsigned> d_propagatedLiteralsIndex;
 258
 259   /**
 260    * Called by the output channel to propagate literals and facts
 261    * @return false if immediate conflict
 262    */
 263   bool propagate(TNode literal, theory::TheoryId theory);
 264
 265   /**
 266    * Internal method to call the propagation routines and collect the
 267    * propagated literals.
 268    */
 269   void propagate(theory::Theory::Effort effort);
 270
 271   /**
 272    * A variable to mark if we added any lemmas.
 273    */
 274   bool d_lemmasAdded;
 275
 276   /**
 277    * A variable to mark if the OutputChannel was "used" by any theory
 278    * since the start of the last check.  If it has been, we require
 279    * a FULL_EFFORT check before exiting and reporting SAT.
 280    *
 281    * See the documentation for the needCheck() function, below.
 282    */
 283   bool d_outputChannelUsed;
 284
 285   /** Atom requests from lemmas */
 286   AtomRequests d_atomRequests;
 287
 288   /**
 289    * Adds a new lemma, returning its status.
 290    * @param node the lemma
 291    * @param negated should the lemma be asserted negated
 292    * @param p the properties of the lemma.
 293    */
 294   theory::LemmaStatus lemma(TNode node,
 295                             ProofRule rule,
 296                             bool negated,
 297                             theory::LemmaProperty p,
 298                             theory::TheoryId atomsTo);
 299
 300   /** Enusre that the given atoms are send to the given theory */
 301   void ensureLemmaAtoms(const std::vector<TNode>& atoms, theory::TheoryId theory);
 302
 303   /** sort inference module */
 304   SortInference d_sortInfer;
 305
 306   /** The theory preprocessor */
 307   theory::TheoryPreprocessor d_tpp;
 308
 309   /** Time spent in theory combination */
 310   TimerStat d_combineTheoriesTime;
 311
 312   Node d_true;
 313   Node d_false;
 314
 315   /** Whether we were just interrupted (or not) */
 316   bool d_interrupted;
 317   ResourceManager* d_resourceManager;
 318
 319  public:
 320   /** Constructs a theory engine */
 321   TheoryEngine(context::Context* context,
 322                context::UserContext* userContext,
 323                ResourceManager* rm,
 324                RemoveTermFormulas& iteRemover,
 325                const LogicInfo& logic);
 326
 327   /** Destroys a theory engine */
 328   ~TheoryEngine();
 329
 330   void interrupt();
 331
 332   /** "Spend" a resource during a search or preprocessing.*/
 333   void spendResource(ResourceManager::Resource r);
 334
 335   /**
 336    * Adds a theory. Only one theory per TheoryId can be present, so if
 337    * there is another theory it will be deleted.
 338    */
 339   template <class TheoryClass>
 340   inline void addTheory(theory::TheoryId theoryId)
 341   {
 342     Assert(d_theoryTable[theoryId] == NULL && d_theoryOut[theoryId] == NULL);
 343     d_theoryOut[theoryId] = new theory::EngineOutputChannel(this, theoryId);
 344     d_theoryTable[theoryId] = new TheoryClass(d_context,
 345                                               d_userContext,
 346                                               *d_theoryOut[theoryId],
 347                                               theory::Valuation(this),
 348                                               d_logicInfo,
 349                                               nullptr);
 350     theory::Rewriter::registerTheoryRewriter(
 351         theoryId, d_theoryTable[theoryId]->getTheoryRewriter());
 352   }
 353
 354   void setPropEngine(prop::PropEngine* propEngine)
 355   {
 356     d_propEngine = propEngine;
 357   }
 358
 359   /**
 360    * Called when all initialization of options/logic is done, after theory
 361    * objects have been created.
 362    *
 363    * This initializes the quantifiers engine, the "official" equality engines
 364    * of each theory as required, and the model and model builder utilities.
 365    */
 366   void finishInit();
 367
 368   /**
 369    * Get a pointer to the underlying propositional engine.
 370    */
 371   inline prop::PropEngine* getPropEngine() const {
 372     return d_propEngine;
 373   }
 374
 375   /**
 376    * Get a pointer to the underlying sat context.
 377    */
 378   inline context::Context* getSatContext() const {
 379     return d_context;
 380   }
 381
 382   /**
 383    * Get a pointer to the underlying user context.
 384    */
 385   inline context::Context* getUserContext() const {
 386     return d_userContext;
 387   }
 388
 389   /**
 390    * Get a pointer to the underlying quantifiers engine.
 391    */
 392   theory::QuantifiersEngine* getQuantifiersEngine() const {
 393     return d_quantEngine;
 394   }
 395   /**
 396    * Get a pointer to the underlying decision manager.
 397    */
 398   theory::DecisionManager* getDecisionManager() const
 399   {
 400     return d_decManager.get();
 401   }
 402
 403  private:
 404   /**
 405    * Queue of nodes for pre-registration.
 406    */
 407   std::queue<TNode> d_preregisterQueue;
 408
 409   /**
 410    * Boolean flag denoting we are in pre-registration.
 411    */
 412   bool d_inPreregister;
 413
 414   /**
 415    * Did the theories get any new facts since the last time we called
 416    * check()
 417    */
 418   context::CDO<bool> d_factsAsserted;
 419
 420   /**
 421    * Assert the formula to the given theory.
 422    * @param assertion the assertion to send (not necesserily normalized)
 423    * @param original the assertion as it was sent in from the propagating theory
 424    * @param toTheoryId the theory to assert to
 425    * @param fromTheoryId the theory that sent it
 426    */
 427   void assertToTheory(TNode assertion, TNode originalAssertion, theory::TheoryId toTheoryId, theory::TheoryId fromTheoryId);
 428
 429   /**
 430    * Marks a theory propagation from a theory to a theory where a
 431    * theory could be the THEORY_SAT_SOLVER for literals coming from
 432    * or being propagated to the SAT solver. If the receiving theory
 433    * already recieved the literal, the method returns false, otherwise
 434    * it returns true.
 435    *
 436    * @param assertion the normalized assertion being sent
 437    * @param originalAssertion the actual assertion that was sent
 438    * @param toTheoryId the theory that is on the receiving end
 439    * @param fromTheoryId the theory that sent the assertion
 440    * @return true if a new assertion, false if theory already got it
 441    */
 442   bool markPropagation(TNode assertion, TNode originalAssertions, theory::TheoryId toTheoryId, theory::TheoryId fromTheoryId);
 443
 444   /**
 445    * Computes the explanation by travarsing the propagation graph and
 446    * asking relevant theories to explain the propagations. Initially
 447    * the explanation vector should contain only the element (node, theory)
 448    * where the node is the one to be explained, and the theory is the
 449    * theory that sent the literal. The lemmaProofRecipe will contain a list
 450    * of the explanation steps required to produce the original node.
 451    */
 452   void getExplanation(std::vector<NodeTheoryPair>& explanationVector, LemmaProofRecipe* lemmaProofRecipe);
 453
 454  public:
 455   /**
 456    * Signal the start of a new round of assertion preprocessing
 457    */
 458   void preprocessStart();
 459
 460   /**
 461    * Runs theory specific preprocessing on the non-Boolean parts of
 462    * the formula.  This is only called on input assertions, after ITEs
 463    * have been removed.
 464    */
 465   Node preprocess(TNode node);
 466
 467   /** Notify (preprocessed) assertions. */
 468   void notifyPreprocessedAssertions(const std::vector<Node>& assertions);
 469
 470   /** Return whether or not we are incomplete (in the current context). */
 471   inline bool isIncomplete() const { return d_incomplete; }
 472
 473   /**
 474    * Returns true if we need another round of checking.  If this
 475    * returns true, check(FULL_EFFORT) _must_ be called by the
 476    * propositional layer before reporting SAT.
 477    *
 478    * This is especially necessary for incomplete theories that lazily
 479    * output some lemmas on FULL_EFFORT check (e.g. quantifier reasoning
 480    * outputing quantifier instantiations).  In such a case, a lemma can
 481    * be asserted that is simplified away (perhaps it's already true).
 482    * However, we must maintain the invariant that, if a theory uses the
 483    * OutputChannel, it implicitly requests that another check(FULL_EFFORT)
 484    * be performed before exit, even if no new facts are on its fact queue,
 485    * as it might decide to further instantiate some lemmas, precluding
 486    * a SAT response.
 487    */
 488   inline bool needCheck() const {
 489     return d_outputChannelUsed || d_lemmasAdded;
 490   }
 491   /**
 492    * Is the literal lit (possibly) critical for satisfying the input formula in
 493    * the current context? This call is applicable only during collectModelInfo
 494    * or during LAST_CALL effort.
 495    */
 496   bool isRelevant(Node lit) const;
 497   /**
 498    * This is called at shutdown time by the SmtEngine, just before
 499    * destruction.  It is important because there are destruction
 500    * ordering issues between PropEngine and Theory.
 501    */
 502   void shutdown();
 503
 504   /**
 505    * Solve the given literal with a theory that owns it.
 506    */
 507   theory::Theory::PPAssertStatus solve(TNode literal,
 508                                     theory::SubstitutionMap& substitutionOut);
 509
 510   /**
 511    * Preregister a Theory atom with the responsible theory (or
 512    * theories).
 513    */
 514   void preRegister(TNode preprocessed);
 515
 516   /**
 517    * Assert the formula to the appropriate theory.
 518    * @param node the assertion
 519    */
 520   void assertFact(TNode node);
 521
 522   /**
 523    * Check all (currently-active) theories for conflicts.
 524    * @param effort the effort level to use
 525    */
 526   void check(theory::Theory::Effort effort);
 527
 528   /**
 529    * Calls ppStaticLearn() on all theories, accumulating their
 530    * combined contributions in the "learned" builder.
 531    */
 532   void ppStaticLearn(TNode in, NodeBuilder<>& learned);
 533
 534   /**
 535    * Calls presolve() on all theories and returns true
 536    * if one of the theories discovers a conflict.
 537    */
 538   bool presolve();
 539
 540    /**
 541    * Calls postsolve() on all theories.
 542    */
 543   void postsolve();
 544
 545   /**
 546    * Calls notifyRestart() on all active theories.
 547    */
 548   void notifyRestart();
 549
 550   void getPropagatedLiterals(std::vector<TNode>& literals) {
 551     for (; d_propagatedLiteralsIndex < d_propagatedLiterals.size(); d_propagatedLiteralsIndex = d_propagatedLiteralsIndex + 1) {
 552       Debug("getPropagatedLiterals") << "TheoryEngine::getPropagatedLiterals: propagating: " << d_propagatedLiterals[d_propagatedLiteralsIndex] << std::endl;
 553       literals.push_back(d_propagatedLiterals[d_propagatedLiteralsIndex]);
 554     }
 555   }
 556
 557   /**
 558    * Returns the next decision request, or null if none exist. The next
 559    * decision request is a literal that this theory engine prefers the SAT
 560    * solver to make as its next decision. Decision requests are managed by
 561    * the decision manager d_decManager.
 562    */
 563   Node getNextDecisionRequest();
 564
 565   bool properConflict(TNode conflict) const;
 566
 567   /**
 568    * Returns an explanation of the node propagated to the SAT solver.
 569    */
 570   Node getExplanation(TNode node);
 571
 572   /**
 573    * Returns an explanation of the node propagated to the SAT solver and the theory
 574    * that propagated it.
 575    */
 576   Node getExplanationAndRecipe(TNode node, LemmaProofRecipe* proofRecipe);
 577
 578   /**
 579    * Get the pointer to the model object used by this theory engine.
 580    */
 581   theory::TheoryModel* getModel();
 582   /**
 583    * Get the current model for the current set of assertions. This method
 584    * should only be called immediately after a satisfiable or unknown
 585    * response to a check-sat call, and only if produceModels is true.
 586    *
 587    * If the model is not already built, this will cause this theory engine
 588    * to build the model.
 589    *
 590    * If the model is not available (for instance, if the last call to check-sat
 591    * was interrupted), then this returns the null pointer.
 592    */
 593   theory::TheoryModel* getBuiltModel();
 594   /**
 595    * This forces the model maintained by the combination engine to be built
 596    * if it has not been done so already. This should be called only during a
 597    * last call effort check after theory combination is run.
 598    *
 599    * @return true if the model was successfully built (possibly prior to this
 600    * call).
 601    */
 602   bool buildModel();
 603   /** set eager model building
 604    *
 605    * If this method is called, then this TheoryEngine will henceforth build
 606    * its model immediately after every satisfiability check that results
 607    * in a satisfiable or unknown result. The motivation for this mode is to
 608    * accomodate API users that get the model object from the TheoryEngine,
 609    * where we want to ensure that this model is always valid.
 610    * TODO (#2648): revisit this.
 611    */
 612   void setEagerModelBuilding() { d_eager_model_building = true; }
 613
 614   /** get synth solutions
 615    *
 616    * This method returns true if there is a synthesis solution available. This
 617    * is the case if the last call to check satisfiability originated in a
 618    * check-synth call, and the synthesis solver successfully found a solution
 619    * for all active synthesis conjectures.
 620    *
 621    * This method adds entries to sol_map that map functions-to-synthesize with
 622    * their solutions, for all active conjectures. This should be called
 623    * immediately after the solver answers unsat for sygus input.
 624    *
 625    * For details on what is added to sol_map, see
 626    * SynthConjecture::getSynthSolutions.
 627    */
 628   bool getSynthSolutions(std::map<Node, std::map<Node, Node> >& sol_map);
 629
 630   /**
 631    * Get the theory associated to a given Node.
 632    *
 633    * @returns the theory, or NULL if the TNode is
 634    * of built-in type.
 635    */
 636   inline theory::Theory* theoryOf(TNode node) const {
 637     return d_theoryTable[theory::Theory::theoryOf(node)];
 638   }
 639
 640   /**
 641    * Get the theory associated to a the given theory id.
 642    *
 643    * @returns the theory
 644    */
 645   inline theory::Theory* theoryOf(theory::TheoryId theoryId) const {
 646     Assert(theoryId < theory::THEORY_LAST);
 647     return d_theoryTable[theoryId];
 648   }
 649
 650   inline bool isTheoryEnabled(theory::TheoryId theoryId) const {
 651     return d_logicInfo.isTheoryEnabled(theoryId);
 652   }
 653   /** get the logic info used by this theory engine */
 654   const LogicInfo& getLogicInfo() const;
 655   /**
 656    * Returns the equality status of the two terms, from the theory
 657    * that owns the domain type.  The types of a and b must be the same.
 658    */
 659   theory::EqualityStatus getEqualityStatus(TNode a, TNode b);
 660
 661   /**
 662    * Returns the value that a theory that owns the type of var currently
 663    * has (or null if none);
 664    */
 665   Node getModelValue(TNode var);
 666
 667   /**
 668    * Takes a literal and returns an equivalent literal that is guaranteed to be a SAT literal
 669    */
 670   Node ensureLiteral(TNode n);
 671
 672   /**
 673    * Print all instantiations made by the quantifiers module.
 674    */
 675   void printInstantiations( std::ostream& out );
 676
 677   /**
 678    * Print solution for synthesis conjectures found by ce_guided_instantiation module
 679    */
 680   void printSynthSolution( std::ostream& out );
 681
 682   /**
 683    * Get list of quantified formulas that were instantiated
 684    */
 685   void getInstantiatedQuantifiedFormulas( std::vector< Node >& qs );
 686
 687   /**
 688    * Get instantiation methods
 689    *   first inputs forall x.q[x] and returns ( q[a], ..., q[z] )
 690    *   second inputs forall x.q[x] and returns ( a, ..., z )
 691    *   third and fourth return mappings e.g. forall x.q1[x] -> ( q1[a]...q1[z] ) , ... , forall x.qn[x] -> ( qn[a]...qn[z] )
 692    */
 693   void getInstantiations( Node q, std::vector< Node >& insts );
 694   void getInstantiationTermVectors( Node q, std::vector< std::vector< Node > >& tvecs );
 695   void getInstantiations( std::map< Node, std::vector< Node > >& insts );
 696   void getInstantiationTermVectors( std::map< Node, std::vector< std::vector< Node > > >& insts );
 697
 698   /**
 699    * Get instantiated conjunction, returns q[t1] ^ ... ^ q[tn] where t1...tn are current set of instantiations for q.
 700    *   Can be used for quantifier elimination when satisfiable and q[t1] ^ ... ^ q[tn] |= q
 701    */
 702   Node getInstantiatedConjunction( Node q );
 703
 704   /**
 705    * Forwards an entailment check according to the given theoryOfMode.
 706    * See theory.h for documentation on entailmentCheck().
 707    */
 708   std::pair<bool, Node> entailmentCheck(options::TheoryOfMode mode, TNode lit);
 709
 710  private:
 711
 712   /** Dump the assertions to the dump */
 713   void dumpAssertions(const char* tag);
 714
 715   /** For preprocessing pass lifting bit-vectors of size 1 to booleans */
 716 public:
 717
 718   SortInference* getSortInference() { return &d_sortInfer; }
 719
 720   /** Prints the assertions to the debug stream */
 721   void printAssertions(const char* tag);
 722
 723 private:
 724
 725   std::map< std::string, std::vector< theory::Theory* > > d_attr_handle;
 726
 727  public:
 728   /** Set user attribute.
 729    *
 730    * This function is called when an attribute is set by a user.  In SMT-LIBv2
 731    * this is done via the syntax (! n :attr)
 732    */
 733   void setUserAttribute(const std::string& attr,
 734                         Node n,
 735                         const std::vector<Node>& node_values,
 736                         const std::string& str_value);
 737
 738   /** Handle user attribute.
 739    *
 740    * Associates theory t with the attribute attr.  Theory t will be
 741    * notified whenever an attribute of name attr is set.
 742    */
 743   void handleUserAttribute(const char* attr, theory::Theory* t);
 744
 745   /**
 746    * Check that the theory assertions are satisfied in the model.
 747    * This function is called from the smt engine's checkModel routine.
 748    */
 749   void checkTheoryAssertionsWithModel(bool hardFailure);
 750
 751  private:
 752   IntStat d_arithSubstitutionsAdded;
 753
 754 };/* class TheoryEngine */
 755
 756 }/* CVC4 namespace */
 757
 758 #endif /* CVC4__THEORY_ENGINE_H */