cryptominisat 5.8.0

Rust bindings for CryptoMiniSat, a boolean satisfiability solver
/******************************************
Copyright (C) 2009-2020 Authors of CryptoMiniSat, see AUTHORS file

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
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The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
***********************************************/

#ifndef SCCFINDER_H
#define SCCFINDER_H

#include "clause.h"
#include <stack>
#include <set>

namespace CMSat {

class Solver;

class SCCFinder {
    public:
        explicit SCCFinder(Solver* _solver);
        bool performSCC(uint64_t* bogoprops_given = NULL);
        const std::set<BinaryXor>& get_binxors() const;
        size_t get_num_binxors_found() const;
        void clear_binxors();

        struct Stats
        {
            void clear()
            {
                Stats _tmp;
                *this = _tmp;
            }

            uint64_t numCalls = 0;
            double cpu_time = 0.0;
            uint64_t foundXors = 0;
            uint64_t foundXorsNew = 0;
            uint64_t bogoprops = 0;

            Stats& operator+=(const Stats& other)
            {
                numCalls += other.numCalls;
                cpu_time += other.cpu_time;
                foundXors += other.foundXors;
                foundXorsNew += other.foundXorsNew;
                bogoprops += other.bogoprops;

                return *this;
            }

            void print() const
            {
                cout << "c ----- SCC STATS --------" << endl;
                print_stats_line("c time"
                    , cpu_time
                    , float_div(cpu_time, numCalls)
                    , "per call"
                );

                print_stats_line("c called"
                    , numCalls
                    , float_div(foundXorsNew, numCalls)
                    , "new found per call"
                );

                print_stats_line("c found"
                    , foundXorsNew
                    , stats_line_percent(foundXorsNew, foundXors)
                    , "% of all found"
                );

                print_stats_line("c bogoprops"
                    , bogoprops
                    , "% of all found"
                );

                cout << "c ----- SCC STATS END --------" << endl;
            }

            void print_short(Solver* solver) const;
        };

        const Stats& get_stats() const;
        size_t mem_used() const;
        bool depth_warning_triggered() const;

    private:
        void tarjan(const uint32_t vertex);
        bool depth_warning_issued;
        void doit(const Lit lit, const uint32_t vertex);
        void add_bin_xor_in_tmp();

        //temporaries
        uint32_t globalIndex;
        vector<uint32_t> index;
        vector<uint32_t> lowlink;
        std::stack<uint32_t, vector<uint32_t> > stack;
        vector<char> stackIndicator;
        vector<uint32_t> tmp;
        uint32_t depth;

        Solver* solver;
        std::set<BinaryXor> binxors;

        //Stats
        Stats runStats;
        Stats globalStats;
};

inline void SCCFinder::doit(const Lit lit, const uint32_t vertex) {
    // Was successor v' visited?
    if (index[lit.toInt()] ==  std::numeric_limits<uint32_t>::max()) {
        tarjan(lit.toInt());
        depth--;
        lowlink[vertex] = std::min(lowlink[vertex], lowlink[lit.toInt()]);
    } else if (stackIndicator[lit.toInt()])  {
        lowlink[vertex] = std::min(lowlink[vertex], lowlink[lit.toInt()]);
    }
}

inline bool SCCFinder::depth_warning_triggered() const
{
    return depth_warning_issued;
}

inline const SCCFinder::Stats& SCCFinder::get_stats() const
{
    return globalStats;
}

inline const std::set<BinaryXor>& SCCFinder::get_binxors() const
{
    return binxors;
}

inline size_t SCCFinder::get_num_binxors_found() const
{
    return binxors.size();
}

inline void SCCFinder::clear_binxors()
{
    binxors.clear();
}

} //end namespaceC

#endif //SCCFINDER_H