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/****************************************************************************** |
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* Top contributors (to current version): |
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* Andrew Reynolds, Mathias Preiner |
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* |
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* This file is part of the cvc5 project. |
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* |
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* Copyright (c) 2009-2021 by the authors listed in the file AUTHORS |
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* in the top-level source directory and their institutional affiliations. |
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* All rights reserved. See the file COPYING in the top-level source |
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* directory for licensing information. |
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* **************************************************************************** |
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* |
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* dynamic quantifiers splitting |
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*/ |
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#include "cvc5_private.h" |
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#ifndef CVC5__THEORY__QUANT_SPLIT_H |
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#define CVC5__THEORY__QUANT_SPLIT_H |
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#include "context/cdo.h" |
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#include "smt/env_obj.h" |
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#include "theory/quantifiers/quant_module.h" |
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namespace cvc5 { |
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namespace theory { |
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class QuantifiersEngine; |
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namespace quantifiers { |
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/** Quantifiers dynamic splitting |
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* |
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* This module identifies quantified formulas that should be "split", e.g. |
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* based on datatype constructor case splitting. |
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* |
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* An example of a quantified formula that we may split is the following. Let: |
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* optionPair := mkPair( U, U ) | none |
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* where U is an uninterpreted sort. The quantified formula: |
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* forall x : optionPair. P( x ) |
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* may be "split" via the lemma: |
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* forall x : optionPair. P( x ) <=> |
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* ( forall xy : U. P( mkPair( x, y ) ) OR P( none ) ) |
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* |
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* Notice that such splitting may lead to exponential behavior, say if we |
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* quantify over 32 variables of type optionPair above gives 2^32 disjuncts. |
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* This class is used to compute this splitting dynamically, by splitting |
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* one variable per quantified formula at a time. |
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*/ |
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class QuantDSplit : public QuantifiersModule { |
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typedef context::CDHashSet<Node> NodeSet; |
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public: |
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QuantDSplit(Env& env, |
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QuantifiersState& qs, |
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QuantifiersInferenceManager& qim, |
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QuantifiersRegistry& qr, |
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TermRegistry& tr); |
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/** determine whether this quantified formula will be reduced */ |
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void checkOwnership(Node q) override; |
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/* whether this module needs to check this round */ |
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bool needsCheck(Theory::Effort e) override; |
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/* Call during quantifier engine's check */ |
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void check(Theory::Effort e, QEffort quant_e) override; |
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/** check complete for */ |
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bool checkCompleteFor(Node q) override; |
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/** Identify this module (for debugging, dynamic configuration, etc..) */ |
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std::string identify() const override { return "QuantDSplit"; } |
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private: |
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/** list of relevant quantifiers asserted in the current context */ |
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std::map<Node, int> d_quant_to_reduce; |
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/** whether we have instantiated quantified formulas */ |
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NodeSet d_added_split; |
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}; |
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} |
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} |
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} // namespace cvc5 |
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#endif |