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
|
/**CFile****************************************************************
FileName [bmcICheck.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [SAT-based bounded model checking.]
Synopsis [Performs specialized check.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - June 20, 2005.]
Revision [$Id: bmcICheck.c,v 1.00 2005/06/20 00:00:00 alanmi Exp $]
***********************************************************************/
#include "bmc.h"
#include "sat/cnf/cnf.h"
#include "sat/bsat/satStore.h"
#include "aig/gia/giaAig.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline Cnf_Dat_t * Cnf_DeriveGiaRemapped( Gia_Man_t * p )
{
Cnf_Dat_t * pCnf;
Aig_Man_t * pAig = Gia_ManToAigSimple( p );
pAig->nRegs = 0;
pCnf = Cnf_Derive( pAig, Aig_ManCoNum(pAig) );
Aig_ManStop( pAig );
return pCnf;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline void Cnf_DataLiftGia( Cnf_Dat_t * p, Gia_Man_t * pGia, int nVarsPlus )
{
Gia_Obj_t * pObj;
int v;
Gia_ManForEachObj( pGia, pObj, v )
if ( p->pVarNums[Gia_ObjId(pGia, pObj)] >= 0 )
p->pVarNums[Gia_ObjId(pGia, pObj)] += nVarsPlus;
for ( v = 0; v < p->nLiterals; v++ )
p->pClauses[0][v] += 2*nVarsPlus;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
sat_solver * Bmc_DeriveSolver( Gia_Man_t * p, Gia_Man_t * pMiter, Cnf_Dat_t * pCnf, int nFramesMax, int nTimeOut, int fVerbose )
{
sat_solver * pSat;
Vec_Int_t * vLits;
Gia_Obj_t * pObj, * pObj0, * pObj1;
int i, k, iVar0, iVar1, iVarOut;
int VarShift = 0;
// start the SAT solver
pSat = sat_solver_new();
sat_solver_setnvars( pSat, Gia_ManRegNum(p) + Gia_ManCoNum(p) + pCnf->nVars * (nFramesMax + 1) );
sat_solver_set_runtime_limit( pSat, nTimeOut ? nTimeOut * CLOCKS_PER_SEC + Abc_Clock(): 0 );
// add one large OR clause
vLits = Vec_IntAlloc( Gia_ManCoNum(p) );
Gia_ManForEachCo( p, pObj, i )
Vec_IntPush( vLits, Abc_Var2Lit(Gia_ManRegNum(p) + i, 0) );
sat_solver_addclause( pSat, Vec_IntArray(vLits), Vec_IntArray(vLits) + Vec_IntSize(vLits) );
// load the last timeframe
Cnf_DataLiftGia( pCnf, pMiter, Gia_ManRegNum(p) + Gia_ManCoNum(p) );
VarShift += Gia_ManRegNum(p) + Gia_ManCoNum(p);
// add XOR clauses
Gia_ManForEachPo( p, pObj, i )
{
pObj0 = Gia_ManPo( pMiter, 2*i+0 );
pObj1 = Gia_ManPo( pMiter, 2*i+1 );
iVar0 = pCnf->pVarNums[Gia_ObjId(pMiter, pObj0)];
iVar1 = pCnf->pVarNums[Gia_ObjId(pMiter, pObj1)];
iVarOut = Gia_ManRegNum(p) + i;
sat_solver_add_xor( pSat, iVar0, iVar1, iVarOut, 0 );
}
Gia_ManForEachRi( p, pObj, i )
{
pObj0 = Gia_ManRi( pMiter, i );
pObj1 = Gia_ManRi( pMiter, i + Gia_ManRegNum(p) );
iVar0 = pCnf->pVarNums[Gia_ObjId(pMiter, pObj0)];
iVar1 = pCnf->pVarNums[Gia_ObjId(pMiter, pObj1)];
iVarOut = Gia_ManRegNum(p) + Gia_ManPoNum(p) + i;
sat_solver_add_xor_and( pSat, iVarOut, iVar0, iVar1, i );
}
// add timeframe clauses
for ( i = 0; i < pCnf->nClauses; i++ )
if ( !sat_solver_addclause( pSat, pCnf->pClauses[i], pCnf->pClauses[i+1] ) )
assert( 0 );
// add other timeframes
for ( k = 0; k < nFramesMax; k++ )
{
// collect variables of the RO nodes
Vec_IntClear( vLits );
Gia_ManForEachRo( pMiter, pObj, i )
Vec_IntPush( vLits, pCnf->pVarNums[Gia_ObjId(pMiter, pObj)] );
// lift CNF again
Cnf_DataLiftGia( pCnf, pMiter, pCnf->nVars );
VarShift += pCnf->nVars;
// stitch the clauses
Gia_ManForEachRi( pMiter, pObj, i )
{
iVar0 = pCnf->pVarNums[Gia_ObjId(pMiter, pObj)];
iVar1 = Vec_IntEntry( vLits, i );
if ( iVar1 == -1 )
continue;
sat_solver_add_buffer( pSat, iVar0, iVar1, 0 );
}
// add equality clauses for the COs
Gia_ManForEachPo( p, pObj, i )
{
pObj0 = Gia_ManPo( pMiter, 2*i+0 );
pObj1 = Gia_ManPo( pMiter, 2*i+1 );
iVar0 = pCnf->pVarNums[Gia_ObjId(pMiter, pObj0)];
iVar1 = pCnf->pVarNums[Gia_ObjId(pMiter, pObj1)];
sat_solver_add_buffer( pSat, iVar0, iVar1, 0 );
}
Gia_ManForEachRi( p, pObj, i )
{
pObj0 = Gia_ManRi( pMiter, i );
pObj1 = Gia_ManRi( pMiter, i + Gia_ManRegNum(p) );
iVar0 = pCnf->pVarNums[Gia_ObjId(pMiter, pObj0)];
iVar1 = pCnf->pVarNums[Gia_ObjId(pMiter, pObj1)];
sat_solver_add_buffer_enable( pSat, iVar0, iVar1, i, 0 );
}
// add timeframe clauses
for ( i = 0; i < pCnf->nClauses; i++ )
if ( !sat_solver_addclause( pSat, pCnf->pClauses[i], pCnf->pClauses[i+1] ) )
assert( 0 );
}
// sat_solver_compress( pSat );
Cnf_DataLiftGia( pCnf, pMiter, -VarShift );
Vec_IntFree( vLits );
return pSat;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Bmc_PerformICheck( Gia_Man_t * p, int nFramesMax, int nTimeOut, int fEmpty, int fVerbose )
{
int fUseOldCnf = 0;
Gia_Man_t * pMiter, * pTemp;
Cnf_Dat_t * pCnf;
sat_solver * pSat;
Vec_Int_t * vLits, * vUsed;
int i, status, Lit;
int nLitsUsed, nLits, * pLits;
abctime clkStart = Abc_Clock();
assert( nFramesMax > 0 );
assert( Gia_ManRegNum(p) > 0 );
printf( "Solving M-inductiveness for design %s with %d AND nodes and %d flip-flops:\n",
Gia_ManName(p), Gia_ManAndNum(p), Gia_ManRegNum(p) );
// create miter
pTemp = Gia_ManDup( p );
pMiter = Gia_ManMiter( p, pTemp, 0, 1, 1, 0, 0 );
Gia_ManStop( pTemp );
assert( Gia_ManPoNum(pMiter) == 2 * Gia_ManPoNum(p) );
assert( Gia_ManRegNum(pMiter) == 2 * Gia_ManRegNum(p) );
// derive CNF
if ( fUseOldCnf )
pCnf = Cnf_DeriveGiaRemapped( pMiter );
else
{
pMiter = Jf_ManDeriveCnf( pTemp = pMiter, 0 );
Gia_ManStop( pTemp );
pCnf = (Cnf_Dat_t *)pMiter->pData; pMiter->pData = NULL;
}
// collect positive literals
vLits = Vec_IntAlloc( Gia_ManCoNum(p) );
for ( i = 0; i < Gia_ManRegNum(p); i++ )
Vec_IntPush( vLits, Abc_Var2Lit(i, 0) );
// iteratively compute a minimal M-inductive set of next-state functions
nLitsUsed = Vec_IntSize(vLits);
vUsed = Vec_IntAlloc( Vec_IntSize(vLits) );
while ( 1 )
{
int fChanges = 0;
// derive SAT solver
pSat = Bmc_DeriveSolver( p, pMiter, pCnf, nFramesMax, nTimeOut, fVerbose );
// sat_solver_bookmark( pSat );
if ( fEmpty )
status = sat_solver_solve( pSat, NULL, NULL, (ABC_INT64_T)0, (ABC_INT64_T)0, (ABC_INT64_T)0, (ABC_INT64_T)0 );
else
status = sat_solver_solve( pSat, Vec_IntArray(vLits), Vec_IntArray(vLits) + Vec_IntSize(vLits), (ABC_INT64_T)0, (ABC_INT64_T)0, (ABC_INT64_T)0, (ABC_INT64_T)0 );
if ( status == l_Undef )
{
printf( "Timeout reached after %d seconds.\n", nTimeOut );
break;
}
if ( status == l_True )
{
printf( "The problem is satisfiable (the current set is not M-inductive).\n" );
break;
}
assert( status == l_False );
// call analize_final
nLits = sat_solver_final( pSat, &pLits );
// mark used literals
Vec_IntFill( vUsed, Vec_IntSize(vLits), 0 );
for ( i = 0; i < nLits; i++ )
Vec_IntWriteEntry( vUsed, Abc_Lit2Var(pLits[i]), 1 );
// check if there are any positive unused
Vec_IntForEachEntry( vLits, Lit, i )
{
assert( i == Abc_Lit2Var(Lit) );
if ( Abc_LitIsCompl(Lit) )
continue;
if ( Vec_IntEntry(vUsed, i) )
continue;
// positive literal became unused
Vec_IntWriteEntry( vLits, i, Abc_LitNot(Lit) );
nLitsUsed--;
fChanges = 1;
}
// report the results
printf( "M =%4d : AIG =%8d. SAT vars =%8d. SAT conf =%8d. S =%6d. (%6.2f %%) ",
nFramesMax, (nFramesMax+1) * Gia_ManAndNum(pMiter),
Gia_ManRegNum(p) + Gia_ManCoNum(p) + sat_solver_nvars(pSat),
sat_solver_nconflicts(pSat), nLitsUsed, 100.0 * nLitsUsed / Gia_ManRegNum(p) );
Abc_PrintTime( 1, "Time", Abc_Clock() - clkStart );
// count the number of negative literals
sat_solver_delete( pSat );
if ( !fChanges || fEmpty )
break;
// break;
// sat_solver_rollback( pSat );
}
Cnf_DataFree( pCnf );
Gia_ManStop( pMiter );
Vec_IntFree( vLits );
Vec_IntFree( vUsed );
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END
|
