PbSolver_convert.cc

/*****************************************************************************[PbSolver_convert.cc]
Copyright (c) 2005-2010, Niklas Een, Niklas Sorensson

KP-MiniSat+ based on MiniSat+ -- Copyright (c) 2018-2020 Michał Karpiński, Marek Piotrów

UWrMaxSat based on KP-MiniSat+ -- Copyright (c) 2019-2020 Marek Piotrów

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#include "PbSolver.h"
#include "Hardware.h"
//#include "Sort.h"
#include<algorithm>
//-------------------------------------------------------------------------------------------------
void    linearAddition (const Linear& c, vec<Formula>& out);        // From: PbSolver_convertAdd.C
Formula buildConstraint(const Linear& c, bool soft_constr = true, int max_cost = INT_MAX);   // From: PbSolver_convertSort.C
Formula convertToBdd   (const Linear& c, int max_cost = INT_MAX);   // From: PbSolver_convertBdd.C
//-------------------------------------------------------------------------------------------------

void clear_shared_formulas() {
    extern void clear_clausifier_static_maps();

    FEnv::clear(); FEnv::stack.clear();
    clear_clausifier_static_maps();
}

bool cmpLT(Linear *p, Linear *q) { return p != NULL && (q == NULL || p->size < q->size); }

bool PbSolver::convertPbs(bool first_call)
{
    vec<Formula>    converted_constrs;
    ConvertT saved_opt_convert = opt_convert;
    int nvars = sat_solver.nVars(), ncls = sat_solver.nClauses();

    if (first_call){
        if (!opt_maxsat) findIntervals();
        if (!rewriteAlmostClauses()) {
            sat_solver.addEmptyClause();
            return false;
        }
        //if (opt_reuse_sorters)
            std::stable_sort(&constrs[0], &constrs[0]+constrs.size(), cmpLT);
    }

    for (int i = 0; i < constrs.size(); i++) {
        if (constrs[i] == NULL) continue;
        Linear& c   = *constrs[i]; assert(c.lo != Int_MIN || c.hi != Int_MAX);

        if (opt_verbosity >= 2) 
            if (first_call && !opt_maxsat) /**/ reportf("---[%4d]---> ", constrs.size() - 1 - i); 
        try {
            if (opt_convert == ct_Sorters)
                converted_constrs.push(buildConstraint(c, !first_call)), first_call ? ++srtEncodings : ++srtOptEncodings;
            else if (opt_convert == ct_Adders)
                linearAddition(c, converted_constrs), first_call ? ++addEncodings : ++addOptEncodings;
            else if (opt_convert == ct_BDDs)
                converted_constrs.push(convertToBdd(c)), first_call ? ++bddEncodings : ++bddOptEncodings;
            else if (opt_convert == ct_Mixed) {
                int adder_cost = estimatedAdderCost(c);
                Formula result = buildConstraint(c, !first_call, (int)(adder_cost * opt_sort_thres)); 
                if (result == _undef_) {
                    result = convertToBdd(c, (int)(adder_cost * opt_bdd_thres));
                    if (result != _undef_)
                        if (!first_call) opt_convert = ct_BDDs, ++bddOptEncodings; else ++bddEncodings; 
                } else if (!first_call) opt_convert = ct_Sorters, ++srtOptEncodings; else ++srtEncodings;
                if (result == _undef_) linearAddition(c, converted_constrs), first_call ? ++addEncodings : ++addOptEncodings;
                else converted_constrs.push(result);
            } else assert(false);
            if (first_call || !(opt_maxsat_msu && opt_shared_fmls && opt_minimization == 1)) {
                constrs[i]->~Linear(), constrs[i] = NULL;
                if (!opt_shared_fmls && !opt_reuse_sorters && FEnv::nodes.size() >= 100000) { 
                    clausify(sat_solver, converted_constrs); converted_constrs.clear();
                }
            }
            opt_convert = saved_opt_convert;
        } catch (std::bad_alloc& ba) {
	    FEnv::pop(); i-=1;
	    if (opt_convert == ct_Sorters)  { opt_convert = ct_BDDs; continue; }
	    if (opt_convert != ct_Adders)  { opt_convert = ct_Adders; continue; }
            else {
	        reportf("Out of memery in converting constraints: %s\n",ba.what());
	        _Exit(0);
	    }
        }
        if (!okay()) return false;
    }

    try {
        if (first_call || !(opt_maxsat_msu && opt_shared_fmls && opt_minimization == 1)) {
            constrs.clear(), mem.clear();
            if (first_call) opt_reuse_sorters = false;
            clausify(sat_solver, converted_constrs);
        } else {
            vec<Lit> out;
            clausify(sat_solver, converted_constrs, out);
            for (int i = 0, j = 0; i < constrs.size(); i++) 
                if (constrs[i] != NULL) constrs[i]->lit = out[j++];
        }
        if (opt_verbosity >=2 && ((nvars -= sat_solver.nVars()) < 0 | (ncls -= sat_solver.nClauses()) < 0)) 
            reportf("New vars/cls: %d/%d\n", -nvars, -ncls);
    } catch (std::bad_alloc& ba) {
      reportf("Out of memery in clausifying constraints: %s\n",ba.what());
      _Exit(0);
    }
    return okay();
}