/*++
Copyright (c) 2017 Microsoft Corporation

Module Name:

    sat_par.cpp

Abstract:

    Utilities for parallel SAT solving.

Author:

    Nikolaj Bjorner (nbjorner) 2017-1-29.

Revision History:

--*/
#include "sat/sat_par.h"


namespace sat {

    par::par() {}

    void par::exchange(literal_vector const& in, unsigned& limit, literal_vector& out) {
        #pragma omp critical (par_solver)
        {
            if (limit < m_units.size()) {
                // this might repeat some literals.
                out.append(m_units.size() - limit, m_units.c_ptr() + limit);
            }
            for (unsigned i = 0; i < in.size(); ++i) {
                literal lit = in[i];
                if (!m_unit_set.contains(lit.index())) {
                    m_unit_set.insert(lit.index());
                    m_units.push_back(lit);
                }
            }
            limit = m_units.size();
        }
    }
    
};