summaryrefslogtreecommitdiffstats
path: root/src/proof/dch/dchSat.c
blob: 9da185648ff11b42ce9ad4e5d5f5c86a11f1dd8e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
/**CFile****************************************************************

  FileName    [dchSat.c]

  SystemName  [ABC: Logic synthesis and verification system.]

  PackageName [Choice computation for tech-mapping.]

  Synopsis    [Calls to the SAT solver.]

  Author      [Alan Mishchenko]
  
  Affiliation [UC Berkeley]

  Date        [Ver. 1.0. Started - June 29, 2008.]

  Revision    [$Id: dchSat.c,v 1.00 2008/07/29 00:00:00 alanmi Exp $]

***********************************************************************/

#include "dchInt.h"

ABC_NAMESPACE_IMPL_START


////////////////////////////////////////////////////////////////////////
///                        DECLARATIONS                              ///
////////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////////
///                     FUNCTION DEFINITIONS                         ///
////////////////////////////////////////////////////////////////////////

/**Function*************************************************************

  Synopsis    [Runs equivalence test for the two nodes.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
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;
}


////////////////////////////////////////////////////////////////////////
///                       END OF FILE                                ///
////////////////////////////////////////////////////////////////////////


ABC_NAMESPACE_IMPL_END