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* Simplify adding lemmas * Remove misleading constructor from tmp_assign. The idea is that tmp_assign is only created on the stack and short-lived. Instead of having a convenience constructor that takes a constraint_ref, it's clearer to have an explicit .get() at the call site. * Remove some log messages * bugfix * fix * Add stub for conflict_core * wip * Add example by Clemens
66 lines
1.8 KiB
C++
66 lines
1.8 KiB
C++
/*++
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Copyright (c) 2021 Microsoft Corporation
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Module Name:
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polysat conflict
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Author:
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Nikolaj Bjorner (nbjorner) 2021-03-19
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Jakob Rath 2021-04-6
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--*/
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#pragma once
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#include "math/polysat/constraint.h"
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namespace polysat {
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/// Represents a conflict as core (~negation of clause).
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///
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/// TODO: can probably move some clause_builder functionality into this class.
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class conflict_core {
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// constraint_ref_vector m_constraints;
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vector<constraint_literal> m_constraints;
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bool m_needs_model = true; ///< True iff the conflict depends on the current variable assignment. (If so, additional constraints must be added to the final learned clause.)
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public:
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vector<constraint_literal> const& constraints() const {
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return m_constraints;
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}
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bool empty() const {
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return m_constraints.empty();
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}
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void reset() {
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m_constraints.reset();
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m_needs_model = true;
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}
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// for bailing out with a conflict at the base level
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void set(std::nullptr_t) {
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SASSERT(empty());
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m_constraints.push_back({});
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m_needs_model = false;
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}
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// void set(
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// TODO: set core from conflicting units
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// TODO: set clause
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// TODO: use iterator instead (this method is needed for marking so duplicates don't necessarily have to be skipped)
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unsigned_vector vars(constraint_manager const& cm) const {
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unsigned_vector vars;
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for (auto const& c : m_constraints)
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vars.append(c->vars());
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return vars;
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}
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std::ostream& display(std::ostream& out) const;
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};
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inline std::ostream& operator<<(std::ostream& out, conflict_core const& c) { return c.display(out); }
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}
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