dchSat.c

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#include "dchInt.h"
 
ABC_NAMESPACE_IMPL_START
 



int Dch_NodesAreEquiv( Dch_Man_t * p, Aig_Obj_t * pOld, Aig_Obj_t * pNew )
{
    int nBTLimit = p->pPars->nBTLimit;
    int pLits[2], RetValue, RetValue1, status;
    abctime clk;
    p->nSatCalls++;
 
    // sanity checks
    assert( !Aig_IsComplement(pNew) );
    assert( !Aig_IsComplement(pOld) );
    assert( pNew != pOld );
 
    p->nCallsSince++;  // experiment with this!!!
    
    // check if SAT solver needs recycling
    if ( p->pSat == NULL || 
        (p->pPars->nSatVarMax && 
         p->nSatVars > p->pPars->nSatVarMax && 
         p->nCallsSince > p->pPars->nCallsRecycle) )
        Dch_ManSatSolverRecycle( p );
 
    // if the nodes do not have SAT variables, allocate them
    Dch_CnfNodeAddToSolver( p, pOld );
    Dch_CnfNodeAddToSolver( p, pNew );
 
    // propage unit clauses
    if ( p->pSat->qtail != p->pSat->qhead )
    {
        status = sat_solver_simplify(p->pSat);
        assert( status != 0 );
        assert( p->pSat->qtail == p->pSat->qhead );
    }
 
    // solve under assumptions
    // A = 1; B = 0     OR     A = 1; B = 1 
    pLits[0] = toLitCond( Dch_ObjSatNum(p,pOld), 0 );
    pLits[1] = toLitCond( Dch_ObjSatNum(p,pNew), pOld->fPhase == pNew->fPhase );
    if ( p->pPars->fPolarFlip )
    {
        if ( pOld->fPhase )  pLits[0] = lit_neg( pLits[0] );
        if ( pNew->fPhase )  pLits[1] = lit_neg( pLits[1] );
    }
//Sat_SolverWriteDimacs( p->pSat, "temp.cnf", pLits, pLits + 2, 1 );
clk = Abc_Clock();
    RetValue1 = sat_solver_solve( p->pSat, pLits, pLits + 2, 
        (ABC_INT64_T)nBTLimit, (ABC_INT64_T)0, (ABC_INT64_T)0, (ABC_INT64_T)0 );
p->timeSat += Abc_Clock() - clk;
    if ( RetValue1 == l_False )
    {
p->timeSatUnsat += Abc_Clock() - clk;
        pLits[0] = lit_neg( pLits[0] );
        pLits[1] = lit_neg( pLits[1] );
        RetValue = sat_solver_addclause( p->pSat, pLits, pLits + 2 );
        assert( RetValue );
        p->nSatCallsUnsat++;
    }
    else if ( RetValue1 == l_True )
    {
p->timeSatSat += Abc_Clock() - clk;
        p->nSatCallsSat++;
        return 0;
    }
    else // if ( RetValue1 == l_Undef )
    {
p->timeSatUndec += Abc_Clock() - clk;
        p->nSatFailsReal++;
        return -1;
    }
 
    // if the old node was constant 0, we already know the answer
    if ( pOld == Aig_ManConst1(p->pAigFraig) )
    {
        p->nSatProof++;
        return 1;
    }
 
    // solve under assumptions
    // A = 0; B = 1     OR     A = 0; B = 0 
    pLits[0] = toLitCond( Dch_ObjSatNum(p,pOld), 1 );
    pLits[1] = toLitCond( Dch_ObjSatNum(p,pNew), pOld->fPhase ^ pNew->fPhase );
    if ( p->pPars->fPolarFlip )
    {
        if ( pOld->fPhase )  pLits[0] = lit_neg( pLits[0] );
        if ( pNew->fPhase )  pLits[1] = lit_neg( pLits[1] );
    }
clk = Abc_Clock();
    RetValue1 = sat_solver_solve( p->pSat, pLits, pLits + 2, 
        (ABC_INT64_T)nBTLimit, (ABC_INT64_T)0, (ABC_INT64_T)0, (ABC_INT64_T)0 );
p->timeSat += Abc_Clock() - clk;
    if ( RetValue1 == l_False )
    {
p->timeSatUnsat += Abc_Clock() - clk;
        pLits[0] = lit_neg( pLits[0] );
        pLits[1] = lit_neg( pLits[1] );
        RetValue = sat_solver_addclause( p->pSat, pLits, pLits + 2 );
        assert( RetValue );
        p->nSatCallsUnsat++;
    }
    else if ( RetValue1 == l_True )
    {
p->timeSatSat += Abc_Clock() - clk;
        p->nSatCallsSat++;
        return 0;
    }
    else // if ( RetValue1 == l_Undef )
    {
p->timeSatUndec += Abc_Clock() - clk;
        p->nSatFailsReal++;
        return -1;
    }
    // return SAT proof
    p->nSatProof++;
    return 1;
}
 

 
 
ABC_NAMESPACE_IMPL_END