satSolver2.h

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MiniSat -- Copyright (c) 2005, Niklas Sorensson
http://www.cs.chalmers.se/Cs/Research/FormalMethods/MiniSat/

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// Modified to compile with MS Visual Studio 6.0 by Alan Mishchenko

#ifndef ABC__sat__bsat__satSolver2_h
#define ABC__sat__bsat__satSolver2_h
 

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

#include "satVec.h"
#include "satClause.h"
#include "misc/vec/vecSet.h"
#include "satProof2.h"

ABC_NAMESPACE_HEADER_START

//#define USE_FLOAT_ACTIVITY2

//=================================================================================================
// Public interface:

struct sat_solver2_t;
typedef struct sat_solver2_t sat_solver2;
typedef struct Int2_Man_t_ Int2_Man_t;

extern sat_solver2* sat_solver2_new(void);
extern void         sat_solver2_delete(sat_solver2* s);

extern int          sat_solver2_addclause(sat_solver2* s, lit* begin, lit* end, int Id);
extern int          sat_solver2_simplify(sat_solver2* s);
extern int          sat_solver2_solve(sat_solver2* s, lit* begin, lit* end, ABC_INT64_T nConfLimit, ABC_INT64_T nInsLimit, ABC_INT64_T nConfLimitGlobal, ABC_INT64_T nInsLimitGlobal);
extern void         sat_solver2_rollback(sat_solver2* s);
extern void         sat_solver2_reducedb(sat_solver2* s);
extern double       sat_solver2_memory( sat_solver2* s, int fAll );
extern double       sat_solver2_memory_proof( sat_solver2* s );

extern void         sat_solver2_setnvars(sat_solver2* s,int n);

extern void         Sat_Solver2WriteDimacs( sat_solver2 * p, char * pFileName, lit* assumptionsBegin, lit* assumptionsEnd, int incrementVars );
extern void         Sat_Solver2PrintStats( FILE * pFile, sat_solver2 * p );
extern int *        Sat_Solver2GetModel( sat_solver2 * p, int * pVars, int nVars );
extern void         Sat_Solver2DoubleClauses( sat_solver2 * p, int iVar );

// global variables
extern int          var_is_assigned(sat_solver2* s, int v);
extern int          var_is_partA   (sat_solver2* s, int v);
extern void         var_set_partA  (sat_solver2* s, int v, int partA);

// proof-based APIs
extern void *       Sat_ProofCore( sat_solver2 * s );
extern void *       Sat_ProofInterpolant( sat_solver2 * s, void * pGloVars );
extern word *       Sat_ProofInterpolantTruth( sat_solver2 * s, void * pGloVars );
extern void         Sat_ProofCheck( sat_solver2 * s );

// interpolation APIs
extern Int2_Man_t * Int2_ManStart( sat_solver2 * pSat, int * pGloVars, int nGloVars );
extern void         Int2_ManStop( Int2_Man_t * p );
extern int          Int2_ManChainStart( Int2_Man_t * p, clause * c );
extern int          Int2_ManChainResolve( Int2_Man_t * p, clause * c, int iLit, int varA );
extern void *       Int2_ManReadInterpolant( sat_solver2 * s );


//=================================================================================================
// Solver representation:

struct varinfo_t;
typedef struct varinfo2_t varinfo2;

struct sat_solver2_t
{
    int             size;           // nof variables
    int             cap;            // size of varmaps
    int             qhead;          // Head index of queue.
    int             qtail;          // Tail index of queue.

    int             root_level;     // Level of first proper decision.
    double          random_seed;
    double          progress_estimate;
    int             verbosity;      // Verbosity level. 0=silent, 1=some progress report, 2=everything    // activities

#ifdef USE_FLOAT_ACTIVITY2
    double          var_inc;        // Amount to bump next variable with.
    double          var_decay;      // INVERSE decay factor for variable activity: stores 1/decay. 
    float           cla_inc;        // Amount to bump next clause with.
    float           cla_decay;      // INVERSE decay factor for clause activity: stores 1/decay.
    double*         activity;       // A heuristic measurement of the activity of a variable.
#else
    int             var_inc;        // Amount to bump next variable with.
    int             var_inc2;       // Amount to bump next variable with.
    int             cla_inc;        // Amount to bump next clause with.
    unsigned*       activity;       // A heuristic measurement of the activity of a variable
    unsigned*       activity2;      // backup variable activity
#endif

    int             nUnits;         // the total number of unit clauses
    int             nof_learnts;    // the number of clauses to trigger reduceDB
    int             nLearntMax;     // enables using reduce DB method
    int             nLearntStart;   // starting learned clause limit
    int             nLearntDelta;   // delta of learned clause limit
    int             nLearntRatio;   // ratio percentage of learned clauses
    int             nDBreduces;     // number of DB reductions
    int             fNotUseRandom;  // do not allow random decisions with a fixed probability
    int             fSkipSimplify;  // set to one to skip simplification of the clause database
    int             fProofLogging;  // enable proof-logging
    int             fVerbose;

    // clauses
    Sat_Mem_t       Mem;
    veci*           wlists;         // watcher lists (for each literal)
    veci            act_clas;       // clause activities
    veci            claProofs;      // clause proofs

    // rollback
    int             iVarPivot;      // the pivot for variables
    int             iTrailPivot;    // the pivot for trail
    int             hProofPivot;    // the pivot for proof records

    // internal state
    varinfo2 *      vi;             // variable information
    int*            levels;         // 
    char*           assigns;        // 
    lit*            trail;          // sequence of assignment and implications
    int*            orderpos;       // Index in variable order.
    cla*            reasons;        // reason clauses
    cla*            units;          // unit clauses
    int*            model;          // If problem is solved, this vector contains the model (contains: lbool).

    veci            tagged;         // (contains: var)
    veci            stack;          // (contains: var)
    veci            order;          // Variable order. (heap) (contains: var)
    veci            trail_lim;      // Separator indices for different decision levels in 'trail'. (contains: int)
    veci            temp_clause;    // temporary storage for a CNF clause
    veci            conf_final;     // If problem is unsatisfiable (possibly under assumptions),
                                    // this vector represent the final conflict clause expressed in the assumptions.
    veci            mark_levels;    // temporary storage for labeled levels
    veci            min_lit_order;  // ordering of removable literals
    veci            min_step_order; // ordering of resolution steps
    veci            learnt_live;    // remaining clauses after reduce DB

    // proof logging
    Vec_Set_t *     pPrf1;          // sequence of proof records
    veci            temp_proof;     // temporary place to store proofs
    int             hLearntLast;    // in proof-logging mode, the ID of the final conflict clause (conf_final)
    int             hProofLast;     // in proof-logging mode, the ID of the final conflict clause (conf_final)
    Prf_Man_t *     pPrf2;          // another proof manager
    double          dPrfMemory;     // memory used by the proof-logger
    Int2_Man_t *    pInt2;          // interpolation manager
    int             tempInter;      // temporary storage for the interpolant

    // statistics
    stats_t         stats;
    ABC_INT64_T     nConfLimit;     // external limit on the number of conflicts
    ABC_INT64_T     nInsLimit;      // external limit on the number of implications
    abctime         nRuntimeLimit;  // external limit on runtime
};

static inline clause * clause2_read( sat_solver2 * s, cla h )                  { return Sat_MemClauseHand( &s->Mem, h ); }
static inline int      clause2_proofid(sat_solver2* s, clause* c, int varA)    { return c->lrn ? (veci_begin(&s->claProofs)[clause_id(c)]<<2) | (varA<<1) : (clause_id(c)<<2) | (varA<<1) | 1; }

// these two only work after creating a clause before the solver is called
static inline int   clause2_is_partA (sat_solver2* s, int h)                   { return clause2_read(s, h)->partA;       }
static inline void  clause2_set_partA(sat_solver2* s, int h, int partA)        { clause2_read(s, h)->partA = partA;      }
static inline int   clause2_id(sat_solver2* s, int h)                          { return clause_id(clause2_read(s, h));   }
static inline void  clause2_set_id(sat_solver2* s, int h, int id)              { clause_set_id(clause2_read(s, h), id);  }

//=================================================================================================
// Public APIs:

static inline int sat_solver2_nvars(sat_solver2* s)
{
    return s->size;
}

static inline int sat_solver2_nclauses(sat_solver2* s)
{
    return (int)s->stats.clauses;
}

static inline int sat_solver2_nlearnts(sat_solver2* s)
{
    return (int)s->stats.learnts;
}

static inline int sat_solver2_nconflicts(sat_solver2* s)
{
    return (int)s->stats.conflicts;
}

static inline int sat_solver2_var_value( sat_solver2* s, int v ) 
{
    assert( v >= 0 && v < s->size );
    return (int)(s->model[v] == l_True);
}
static inline int sat_solver2_var_literal( sat_solver2* s, int v ) 
{
    assert( v >= 0 && v < s->size );
    return toLitCond( v, s->model[v] != l_True );
}
static inline void sat_solver2_act_var_clear(sat_solver2* s) 
{
    int i;
    for (i = 0; i < s->size; i++)
        s->activity[i] = 0;//.0;
    s->var_inc = 1.0;
}

static inline int sat_solver2_final(sat_solver2* s, int ** ppArray)
{
    *ppArray = s->conf_final.ptr;
    return s->conf_final.size;
}

static inline abctime sat_solver2_set_runtime_limit(sat_solver2* s, abctime Limit)
{
    abctime temp = s->nRuntimeLimit;
    s->nRuntimeLimit = Limit;
    return temp;
}

static inline int sat_solver2_set_learntmax(sat_solver2* s, int nLearntMax)
{
    int temp = s->nLearntMax;
    s->nLearntMax = nLearntMax;
    return temp;
}

static inline void sat_solver2_bookmark(sat_solver2* s)
{
    assert( s->qhead == s->qtail );
    s->iVarPivot    = s->size;
    s->iTrailPivot  = s->qhead;
    if ( s->pPrf1 )
        s->hProofPivot  = Vec_SetHandCurrent(s->pPrf1);
    Sat_MemBookMark( &s->Mem );
    if ( s->activity2 )
    {
        s->var_inc2 = s->var_inc;
        memcpy( s->activity2, s->activity, sizeof(unsigned) * s->iVarPivot );
    }
}

static inline int sat_solver2_add_const( sat_solver2 * pSat, int iVar, int fCompl, int fMark, int Id )
{
    lit Lits[1];
    int Cid;
    assert( iVar >= 0 );

    Lits[0] = toLitCond( iVar, fCompl );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 1, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );
    return 1;
}
static inline int sat_solver2_add_buffer( sat_solver2 * pSat, int iVarA, int iVarB, int fCompl, int fMark, int Id )
{
    lit Lits[2];
    int Cid;
    assert( iVarA >= 0 && iVarB >= 0 );

    Lits[0] = toLitCond( iVarA, 0 );
    Lits[1] = toLitCond( iVarB, !fCompl );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 2, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );

    Lits[0] = toLitCond( iVarA, 1 );
    Lits[1] = toLitCond( iVarB, fCompl );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 2, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );
    return 2;
}
static inline int sat_solver2_add_and( sat_solver2 * pSat, int iVar, int iVar0, int iVar1, int fCompl0, int fCompl1, int fMark, int Id )
{
    lit Lits[3];
    int Cid;

    Lits[0] = toLitCond( iVar, 1 );
    Lits[1] = toLitCond( iVar0, fCompl0 );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 2, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );

    Lits[0] = toLitCond( iVar, 1 );
    Lits[1] = toLitCond( iVar1, fCompl1 );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 2, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );

    Lits[0] = toLitCond( iVar, 0 );
    Lits[1] = toLitCond( iVar0, !fCompl0 );
    Lits[2] = toLitCond( iVar1, !fCompl1 );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 3, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );
    return 3;
}
static inline int sat_solver2_add_xor( sat_solver2 * pSat, int iVarA, int iVarB, int iVarC, int fCompl, int fMark, int Id )
{
    lit Lits[3];
    int Cid;
    assert( iVarA >= 0 && iVarB >= 0 && iVarC >= 0 );

    Lits[0] = toLitCond( iVarA, !fCompl );
    Lits[1] = toLitCond( iVarB, 1 );
    Lits[2] = toLitCond( iVarC, 1 );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 3, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );

    Lits[0] = toLitCond( iVarA, !fCompl );
    Lits[1] = toLitCond( iVarB, 0 );
    Lits[2] = toLitCond( iVarC, 0 );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 3, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );

    Lits[0] = toLitCond( iVarA, fCompl );
    Lits[1] = toLitCond( iVarB, 1 );
    Lits[2] = toLitCond( iVarC, 0 );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 3, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );

    Lits[0] = toLitCond( iVarA, fCompl );
    Lits[1] = toLitCond( iVarB, 0 );
    Lits[2] = toLitCond( iVarC, 1 );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 3, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );
    return 4;
}
static inline int sat_solver2_add_constraint( sat_solver2 * pSat, int iVar, int iVar2, int fCompl, int fMark, int Id )
{
    lit Lits[2];
    int Cid;
    assert( iVar >= 0 );

    Lits[0] = toLitCond( iVar, fCompl );
    Lits[1] = toLitCond( iVar2, 0 );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 2, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );

    Lits[0] = toLitCond( iVar, fCompl );
    Lits[1] = toLitCond( iVar2, 1 );
    Cid = sat_solver2_addclause( pSat, Lits, Lits + 2, Id );
    if ( fMark )
        clause2_set_partA( pSat, Cid, 1 );
    return 2;
}


ABC_NAMESPACE_HEADER_END

#endif