/*! \file theory_inference_manager.h
** \verbatim
** Top contributors (to current version):
- ** Andrew Reynolds
+ ** Andrew Reynolds, Mathias Preiner, Gereon Kremer
** This file is part of the CVC4 project.
** Copyright (c) 2009-2020 by the authors listed in the file AUTHORS
- ** in the top-level source directory) and their institutional affiliations.
+ ** in the top-level source directory and their institutional affiliations.
** All rights reserved. See the file COPYING in the top-level source
** directory for licensing information.\endverbatim
**
* of theory.
*/
void setEqualityEngine(eq::EqualityEngine* ee);
+ /**
+ * Are proofs enabled in this inference manager? Returns true if the proof
+ * node manager pnm provided to the constructor of this class was non-null.
+ */
+ bool isProofEnabled() const;
/**
* Reset, which resets counters regarding the number of added lemmas and
* internal facts. This method should be manually called by the theory at
* beginning of this loop and repeat its strategy while hasAddedFact is true.
*/
void reset();
+ /**
+ * Returns true if we are in conflict, or if we have sent a lemma or fact
+ * since the last call to reset.
+ */
+ bool hasSent() const;
+ /** Get the underlying proof equality engine */
+ eq::ProofEqEngine* getProofEqEngine();
//--------------------------------------- propagations
/**
* T-propagate literal lit, possibly encountered by equality engine,
void conflict(TNode conf);
/**
* Raise trusted conflict tconf (of any form) where a proof generator has
- * been provided in a custom way.
+ * been provided (as part of the trust node) in a custom way.
*/
void trustedConflict(TrustNode tconf);
+ /**
+ * Explain and send conflict from contradictory facts. This method is called
+ * when the proof rule id with premises exp and arguments args concludes
+ * false. This method sends a trusted conflict corresponding to the official
+ * equality engine's explanation of literals in exp, with the proof equality
+ * engine as the proof generator (if it exists).
+ */
+ void conflictExp(PfRule id,
+ const std::vector<Node>& exp,
+ const std::vector<Node>& args);
+ /**
+ * Make the trust node corresponding to the conflict of the above form. It is
+ * the responsibility of the caller to subsequently call trustedConflict with
+ * the returned trust node.
+ */
+ TrustNode mkConflictExp(PfRule id,
+ const std::vector<Node>& exp,
+ const std::vector<Node>& args);
+ /**
+ * Explain and send conflict from contradictory facts. This method is called
+ * when proof generator pg has a proof of false from free assumptions exp.
+ * This method sends a trusted conflict corresponding to the official
+ * equality engine's explanation of literals in exp, with the proof equality
+ * engine as the proof generator (if it exists), where pg provides the
+ * final step(s) of this proof during this call.
+ */
+ void conflictExp(const std::vector<Node>& exp, ProofGenerator* pg);
+ /**
+ * Make the trust node corresponding to the conflict of the above form. It is
+ * the responsibility of the caller to subsequently call trustedConflict with
+ * the returned trust node.
+ */
+ TrustNode mkConflictExp(const std::vector<Node>& exp, ProofGenerator* pg);
//--------------------------------------- lemmas
/**
* Send (trusted) lemma lem with property p on the output channel.
bool lemma(TNode lem,
LemmaProperty p = LemmaProperty::NONE,
bool doCache = true);
+ /**
+ * Explained lemma. This should be called when
+ * ( exp => conc )
+ * is a valid theory lemma. This method adds a lemma where part of exp
+ * is replaced by its explanation according to the official equality engine
+ * of the theory.
+ *
+ * In particular, this method adds a lemma on the output channel of the form
+ * ( ^_{e in exp \ noExplain} EXPLAIN(e) ^ noExplain ) => conc
+ * where EXPLAIN(e) returns the explanation of literal e according to the
+ * official equality engine of the theory. Note that noExplain is the *subset*
+ * of exp that should not be explained.
+ *
+ * @param conc The conclusion of the lemma
+ * @param id The proof rule concluding conc
+ * @param exp The set of (all) literals that imply conc
+ * @param noExplain The subset of exp that should not be explained by the
+ * equality engine
+ * @param args The arguments to the proof step concluding conc
+ * @param p The property of the lemma
+ * @param doCache Whether to check and add the lemma to the cache
+ * @return true if the lemma was sent on the output channel.
+ */
+ bool lemmaExp(Node conc,
+ PfRule id,
+ const std::vector<Node>& exp,
+ const std::vector<Node>& noExplain,
+ const std::vector<Node>& args,
+ LemmaProperty p = LemmaProperty::NONE,
+ bool doCache = true);
+ /**
+ * Make the trust node for the above method. It is responsibility of the
+ * caller to subsequently call trustedLemma with the returned trust node.
+ */
+ TrustNode mkLemmaExp(Node conc,
+ PfRule id,
+ const std::vector<Node>& exp,
+ const std::vector<Node>& noExplain,
+ const std::vector<Node>& args);
+ /**
+ * Same as above, but where pg can provide a proof of conc from free
+ * assumptions in exp. This sends a trusted lemma on the output channel where
+ * the proof equality engine is the proof generator. The generator pg
+ * is asked to provide the final step(s) of this proof during this call.
+ *
+ * @param conc The conclusion of the lemma
+ * @param exp The set of (all) literals that imply conc
+ * @param noExplain The subset of exp that should not be explained by the
+ * equality engine
+ * @param pg If non-null, the proof generator who can provide a proof of conc.
+ * @param p The property of the lemma
+ * @param doCache Whether to check and add the lemma to the cache
+ * @return true if the lemma was sent on the output channel.
+ */
+ bool lemmaExp(Node conc,
+ const std::vector<Node>& exp,
+ const std::vector<Node>& noExplain,
+ ProofGenerator* pg = nullptr,
+ LemmaProperty p = LemmaProperty::NONE,
+ bool doCache = true);
+ /**
+ * Make the trust node for the above method. It is responsibility of the
+ * caller to subsequently call trustedLemma with the returned trust node.
+ */
+ TrustNode mkLemmaExp(Node conc,
+ const std::vector<Node>& exp,
+ const std::vector<Node>& noExplain,
+ ProofGenerator* pg = nullptr);
/**
* Has this inference manager cached and sent the given lemma (in this user
* context)? This method can be overridden by the particular manager. If not,
*/
virtual bool hasCachedLemma(TNode lem, LemmaProperty p);
/** The number of lemmas we have sent since the last call to reset */
- uint32_t numAddedLemmas() const;
+ uint32_t numSentLemmas() const;
/** Have we added a lemma since the last call to reset? */
- bool hasAddedLemma() const;
+ bool hasSentLemma() const;
//--------------------------------------- internal facts
/**
* Assert internal fact. This is recommended method for asserting "internal"
* @param atom The atom of the fact to assert
* @param pol Its polarity
* @param exp Its explanation, i.e. ( exp => (~) atom ) is valid.
+ * @return true if the fact was processed, i.e. it was asserted to the
+ * equality engine or preNotifyFact returned true.
*/
- void assertInternalFact(TNode atom, bool pol, TNode exp);
+ bool assertInternalFact(TNode atom, bool pol, TNode exp);
/**
* Assert internal fact, with a proof step justification. Notice that if
* proofs are not enabled in this inference manager, then this asserts
* @param id The proof rule identifier of the proof step
* @param exp Its explanation, interpreted as a conjunction
* @param args The arguments of the proof step
+ * @return true if the fact was processed, i.e. it was asserted to the
+ * equality engine or preNotifyFact returned true.
*/
- void assertInternalFact(TNode atom,
+ bool assertInternalFact(TNode atom,
bool pol,
PfRule id,
const std::vector<Node>& exp,
* @param atom The atom of the fact to assert
* @param pol Its polarity
* @param exp Its explanation, interpreted as a conjunction
- * @param pg The proof generator for this step. It must be the case that pf
- * can provide a proof concluding (~) atom from free asumptions in exp in
+ * @param pg The proof generator for this step. If non-null, pg must be able
+ * to provide a proof concluding (~) atom from free asumptions in exp in
* the remainder of the current SAT context.
+ * @return true if the fact was processed, i.e. it was asserted to the
+ * equality engine or preNotifyFact returned true.
*/
- void assertInternalFact(TNode atom,
+ bool assertInternalFact(TNode atom,
bool pol,
const std::vector<Node>& exp,
ProofGenerator* pg);
/** The number of internal facts we have added since the last call to reset */
- uint32_t numAddedFacts() const;
+ uint32_t numSentFacts() const;
/** Have we added a internal fact since the last call to reset? */
- bool hasAddedFact() const;
+ bool hasSentFact() const;
+ //--------------------------------------- phase requirements
+ /**
+ * Set that literal n has SAT phase requirement pol, that is, it should be
+ * decided with polarity pol, for details see OutputChannel::requirePhase.
+ */
+ void requirePhase(TNode n, bool pol);
+
+ /**
+ * Forward to OutputChannel::spendResource() to spend resources.
+ */
+ void spendResource(ResourceManager::Resource r);
+
+ /**
+ * Forward to OutputChannel::safePoint() to spend resources.
+ */
+ void safePoint(ResourceManager::Resource r);
+ /**
+ * Notification from a theory that it realizes it is incomplete at
+ * this context level.
+ */
+ void setIncomplete();
protected:
/**
* Process internal fact. This is a common helper method for the
- * assertInternalFact variants above.
+ * assertInternalFact variants above. Returns true if the fact was processed.
*/
- void processInternalFact(TNode atom,
+ bool processInternalFact(TNode atom,
bool pol,
PfRule id,
const std::vector<Node>& exp,
* conjunctions), return the explanation as a conjunction.
*/
Node mkExplain(TNode n);
+ /**
+ * Explain the set of formulas in exp using the official equality engine of
+ * the theory. We ask the equality engine to explain literals in exp
+ * that do not occur in noExplain, and return unchanged those that occur in
+ * noExplain. Note the vector noExplain should be a subset of exp.
+ */
+ Node mkExplainPartial(const std::vector<Node>& exp,
+ const std::vector<Node>& noExplain);
/**
* Cache that lemma lem is being sent with property p. Return true if it
* did not already exist in the cache maintained by this class. If this
* nodes. Notice that this cache does not depedent on lemma property.
*/
NodeSet d_lemmasSent;
+ /** The number of conflicts sent since the last call to reset. */
+ uint32_t d_numConflicts;
/** The number of lemmas sent since the last call to reset. */
uint32_t d_numCurrentLemmas;
/** The number of internal facts added since the last call to reset. */