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
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
|
/**CFile****************************************************************
FileName [sbdLut.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [SAT-based optimization using internal don't-cares.]
Synopsis [CNF computation.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - June 20, 2005.]
Revision [$Id: sbdLut.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
***********************************************************************/
#include "sbdInt.h"
#include "misc/util/utilTruth.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
// count the number of parameter variables in the structure
int Sbd_ProblemCountParams( int nStrs, Sbd_Str_t * pStr0 )
{
Sbd_Str_t * pStr; int nPars = 0;
for ( pStr = pStr0; pStr < pStr0 + nStrs; pStr++ )
nPars += pStr->fLut ? 1 << pStr->nVarIns : pStr->nVarIns;
return nPars;
}
// add clauses for the structure
int Sbd_ProblemAddClauses( sat_solver * pSat, int nVars, int nStrs, int * pVars, Sbd_Str_t * pStr0 )
{
// variable order: inputs, structure outputs, parameters
Sbd_Str_t * pStr;
int VarOut = nVars;
int VarPar = nVars + nStrs;
int m, k, n, status, pLits[SBD_SIZE_MAX+2];
//printf( "Start par = %d. ", VarPar );
for ( pStr = pStr0; pStr < pStr0 + nStrs; pStr++, VarOut++ )
{
if ( pStr->fLut )
{
int nMints = 1 << pStr->nVarIns;
assert( pStr->nVarIns <= 6 );
for ( m = 0; m < nMints; m++, VarPar++ )
{
for ( k = 0; k < pStr->nVarIns; k++ )
pLits[k] = Abc_Var2Lit( pVars[pStr->VarIns[k]], (m >> k) & 1 );
for ( n = 0; n < 2; n++ )
{
pLits[pStr->nVarIns] = Abc_Var2Lit( pVars[VarPar], n );
pLits[pStr->nVarIns+1] = Abc_Var2Lit( pVars[VarOut], !n );
status = sat_solver_addclause( pSat, pLits, pLits + pStr->nVarIns + 2 );
if ( !status )
return 0;
}
}
}
else
{
assert( pStr->nVarIns <= SBD_DIV_MAX );
for ( k = 0; k < pStr->nVarIns; k++, VarPar++ )
{
for ( n = 0; n < 2; n++ )
{
pLits[0] = Abc_Var2Lit( pVars[VarPar], 1 );
pLits[1] = Abc_Var2Lit( pVars[VarOut], n );
pLits[2] = Abc_Var2Lit( pVars[pStr->VarIns[k]], !n );
status = sat_solver_addclause( pSat, pLits, pLits + 3 );
if ( !status )
return 0;
}
}
}
}
return 1;
}
void Sbd_ProblemAddClausesInit( sat_solver * pSat, int nVars, int nStrs, int * pVars, Sbd_Str_t * pStr0 )
{
Sbd_Str_t * pStr;
int VarPar = nVars + nStrs;
int m, m2, status, pLits[SBD_DIV_MAX];
// make sure selector parameters are mutually exclusive
for ( pStr = pStr0; pStr < pStr0 + nStrs; VarPar += pStr->fLut ? 1 << pStr->nVarIns : pStr->nVarIns, pStr++ )
{
if ( pStr->fLut )
continue;
// one variable should be selected
assert( pStr->nVarIns <= SBD_DIV_MAX );
for ( m = 0; m < pStr->nVarIns; m++ )
pLits[m] = Abc_Var2Lit( pVars[VarPar + m], 0 );
status = sat_solver_addclause( pSat, pLits, pLits + pStr->nVarIns );
assert( status );
// two variables cannot be selected
for ( m = 0; m < pStr->nVarIns; m++ )
for ( m2 = m+1; m2 < pStr->nVarIns; m2++ )
{
pLits[0] = Abc_Var2Lit( pVars[VarPar + m], 1 );
pLits[1] = Abc_Var2Lit( pVars[VarPar + m2], 1 );
status = sat_solver_addclause( pSat, pLits, pLits + 2 );
assert( status );
}
}
}
void Sbd_ProblemPrintSolution( int nStrs, Sbd_Str_t * pStr0, Vec_Int_t * vLits )
{
Sbd_Str_t * pStr;
int m, nIters, iLit = 0;
printf( "Solution found:\n" );
for ( pStr = pStr0; pStr < pStr0 + nStrs; pStr++ )
{
nIters = pStr->fLut ? 1 << pStr->nVarIns : pStr->nVarIns;
printf( "%s%d : ", pStr->fLut ? "LUT":"SEL", (int)(pStr-pStr0) );
for ( m = 0; m < nIters; m++, iLit++ )
printf( "%d", !Abc_LitIsCompl(Vec_IntEntry(vLits, iLit)) );
printf( " {" );
for ( m = 0; m < pStr->nVarIns; m++ )
printf( " %d", pStr->VarIns[m] );
printf( " }\n" );
}
assert( iLit == Vec_IntSize(vLits) );
}
void Sbd_ProblemCollectSolution( int nStrs, Sbd_Str_t * pStr0, Vec_Int_t * vLits )
{
Sbd_Str_t * pStr;
int m, nIters, iLit = 0;
for ( pStr = pStr0; pStr < pStr0 + nStrs; pStr++ )
{
pStr->Res = 0;
if ( pStr->fLut )
{
nIters = 1 << pStr->nVarIns;
for ( m = 0; m < nIters; m++, iLit++ )
if ( !Abc_LitIsCompl(Vec_IntEntry(vLits, iLit)) )
Abc_TtSetBit( &pStr->Res, m );
pStr->Res = Abc_Tt6Stretch( pStr->Res, pStr->nVarIns );
}
else
{
nIters = 0;
for ( m = 0; m < pStr->nVarIns; m++, iLit++ )
if ( !Abc_LitIsCompl(Vec_IntEntry(vLits, iLit)) )
{
pStr->Res = pStr->VarIns[m];
nIters++;
}
assert( nIters == 1 );
}
}
assert( iLit == Vec_IntSize(vLits) );
}
/**Function*************************************************************
Synopsis [Solves QBF problem for the given window.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Sbd_ProblemSolve( Gia_Man_t * p, Vec_Int_t * vMirrors,
int Pivot, Vec_Int_t * vWinObjs, Vec_Int_t * vObj2Var,
Vec_Int_t * vTfo, Vec_Int_t * vRoots,
Vec_Int_t * vDivSet, int nStrs, Sbd_Str_t * pStr0 ) // divisors, structures
{
extern sat_solver * Sbd_ManSatSolver( sat_solver * pSat, Gia_Man_t * p, Vec_Int_t * vMirrors, int Pivot, Vec_Int_t * vWinObjs, Vec_Int_t * vObj2Var, Vec_Int_t * vTfo, Vec_Int_t * vRoots, int fQbf );
int fVerbose = 0;
abctime clk = Abc_Clock();
Vec_Int_t * vLits = Vec_IntAlloc( 100 );
sat_solver * pSatCec = Sbd_ManSatSolver( NULL, p, vMirrors, Pivot, vWinObjs, vObj2Var, vTfo, vRoots, 1 );
sat_solver * pSatQbf = sat_solver_new();
int nVars = Vec_IntSize( vDivSet );
int nPars = Sbd_ProblemCountParams( nStrs, pStr0 );
int VarCecOut = Vec_IntSize(vWinObjs) + Vec_IntSize(vTfo) + Vec_IntSize(vRoots);
int VarCecPar = VarCecOut + nStrs;
int VarQbfPar = 0;
int VarQbfFree = nPars;
int pVarsCec[256];
int pVarsQbf[256];
int i, iVar, iLit, nIters;
int RetValue = 0;
assert( Vec_IntSize(vDivSet) <= SBD_DIV_MAX );
assert( nVars + nStrs + nPars <= 256 );
// collect CEC variables
Vec_IntForEachEntry( vDivSet, iVar, i )
pVarsCec[i] = iVar;
for ( i = 0; i < nStrs; i++ )
pVarsCec[nVars + i] = VarCecOut + i;
for ( i = 0; i < nPars; i++ )
pVarsCec[nVars + nStrs + i] = VarCecPar + i;
// collect QBF variables
for ( i = 0; i < nVars + nStrs; i++ )
pVarsQbf[i] = -1;
for ( i = 0; i < nPars; i++ )
pVarsQbf[nVars + nStrs + i] = VarQbfPar + i;
// add clauses to the CEC problem
Sbd_ProblemAddClauses( pSatCec, nVars, nStrs, pVarsCec, pStr0 );
// create QBF solver
sat_solver_setnvars( pSatQbf, 1000 );
Sbd_ProblemAddClausesInit( pSatQbf, nVars, nStrs, pVarsQbf, pStr0 );
// assume all parameter variables are 0
Vec_IntClear( vLits );
for ( i = 0; i < nPars; i++ )
Vec_IntPush( vLits, Abc_Var2Lit(VarCecPar + i, 1) );
for ( nIters = 0; nIters < (1 << nVars); nIters++ )
{
// check if these parameters solve the problem
int status = sat_solver_solve( pSatCec, Vec_IntArray(vLits), Vec_IntLimit(vLits), 0, 0, 0, 0 );
if ( status == l_False ) // solution found
break;
assert( status == l_True );
if ( fVerbose )
{
printf( "Iter %3d : ", nIters );
for ( i = 0; i < nPars; i++ )
printf( "%d", !Abc_LitIsCompl(Vec_IntEntry(vLits, i)) );
printf( " " );
}
Vec_IntClear( vLits );
// create new QBF variables
for ( i = 0; i < nVars + nStrs; i++ )
pVarsQbf[i] = VarQbfFree++;
// set their values
Vec_IntForEachEntry( vDivSet, iVar, i )
{
iLit = Abc_Var2Lit( pVarsQbf[i], !sat_solver_var_value(pSatCec, iVar) );
status = sat_solver_addclause( pSatQbf, &iLit, &iLit + 1 );
assert( status );
if ( fVerbose )
printf( "%d", sat_solver_var_value(pSatCec, iVar) );
}
iLit = Abc_Var2Lit( pVarsQbf[nVars], sat_solver_var_value(pSatCec, VarCecOut) );
status = sat_solver_addclause( pSatQbf, &iLit, &iLit + 1 );
assert( status );
if ( fVerbose )
printf( " %d\n", !sat_solver_var_value(pSatCec, VarCecOut) );
// add clauses to the QBF problem
if ( !Sbd_ProblemAddClauses( pSatQbf, nVars, nStrs, pVarsQbf, pStr0 ) )
break; // solution does not exist
// check if solution still exists
status = sat_solver_solve( pSatQbf, NULL, NULL, 0, 0, 0, 0 );
if ( status == l_False ) // solution does not exist
break;
assert( status == l_True );
// find the new values of parameters
assert( Vec_IntSize(vLits) == 0 );
for ( i = 0; i < nPars; i++ )
Vec_IntPush( vLits, Abc_Var2Lit(VarCecPar + i, !sat_solver_var_value(pSatQbf, VarQbfPar + i)) );
}
if ( Vec_IntSize(vLits) > 0 )
{
//Sbd_ProblemPrintSolution( nStrs, pStr0, vLits );
Sbd_ProblemCollectSolution( nStrs, pStr0, vLits );
RetValue = 1;
}
sat_solver_delete( pSatCec );
sat_solver_delete( pSatQbf );
Vec_IntFree( vLits );
if ( fVerbose )
Abc_PrintTime( 1, "Time", Abc_Clock() - clk );
return RetValue;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END
|
