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
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
|
/**CFile****************************************************************
FileName [satInter.c]
SystemName [ABC: Logic synthesis and verification system.]
PackageName [SAT sat_solver.]
Synopsis [Interpolation package.]
Author [Alan Mishchenko]
Affiliation [UC Berkeley]
Date [Ver. 1.0. Started - June 20, 2005.]
Revision [$Id: satInter.c,v 1.4 2005/09/16 22:55:03 casem Exp $]
***********************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <time.h>
#include "satStore.h"
#include "aig.h"
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
// variable assignments
static const lit LIT_UNDEF = 0xffffffff;
// interpolation manager
struct Intb_Man_t_
{
// clauses of the problems
Sto_Man_t * pCnf; // the set of CNF clauses for A and B
Vec_Int_t * vVarsAB; // the array of global variables
// various parameters
int fVerbose; // verbosiness flag
int fProofVerif; // verifies the proof
int fProofWrite; // writes the proof file
int nVarsAlloc; // the allocated size of var arrays
int nClosAlloc; // the allocated size of clause arrays
// internal BCP
int nRootSize; // the number of root level assignments
int nTrailSize; // the number of assignments made
lit * pTrail; // chronological order of assignments (size nVars)
lit * pAssigns; // assignments by variable (size nVars)
char * pSeens; // temporary mark (size nVars)
Sto_Cls_t ** pReasons; // reasons for each assignment (size nVars)
Sto_Cls_t ** pWatches; // watched clauses for each literal (size 2*nVars)
// interpolation data
Aig_Man_t * pAig; // the AIG manager for recording the interpolant
int * pVarTypes; // variable type (size nVars) [1=A, 0=B, <0=AB]
Aig_Obj_t ** pInters; // storage for interpolants as truth tables (size nClauses)
int nIntersAlloc; // the allocated size of truth table array
// proof recording
int Counter; // counter of resolved clauses
int * pProofNums; // the proof numbers for each clause (size nClauses)
FILE * pFile; // the file for proof recording
// internal verification
lit * pResLits; // the literals of the resolvent
int nResLits; // the number of literals of the resolvent
int nResLitsAlloc;// the number of literals of the resolvent
// runtime stats
int timeBcp; // the runtime for BCP
int timeTrace; // the runtime of trace construction
int timeTotal; // the total runtime of interpolation
};
// procedure to get hold of the clauses' truth table
static inline Aig_Obj_t ** Intb_ManAigRead( Intb_Man_t * pMan, Sto_Cls_t * pCls ) { return pMan->pInters + pCls->Id; }
static inline void Intb_ManAigClear( Intb_Man_t * pMan, Aig_Obj_t ** p ) { *p = Aig_ManConst0(pMan->pAig); }
static inline void Intb_ManAigFill( Intb_Man_t * pMan, Aig_Obj_t ** p ) { *p = Aig_ManConst1(pMan->pAig); }
static inline void Intb_ManAigCopy( Intb_Man_t * pMan, Aig_Obj_t ** p, Aig_Obj_t ** q ) { *p = *q; }
static inline void Intb_ManAigAnd( Intb_Man_t * pMan, Aig_Obj_t ** p, Aig_Obj_t ** q ) { *p = Aig_And(pMan->pAig, *p, *q); }
static inline void Intb_ManAigOr( Intb_Man_t * pMan, Aig_Obj_t ** p, Aig_Obj_t ** q ) { *p = Aig_Or(pMan->pAig, *p, *q); }
static inline void Intb_ManAigOrNot( Intb_Man_t * pMan, Aig_Obj_t ** p, Aig_Obj_t ** q ) { *p = Aig_Or(pMan->pAig, *p, Aig_Not(*q)); }
static inline void Intb_ManAigOrVar( Intb_Man_t * pMan, Aig_Obj_t ** p, int v ) { *p = Aig_Or(pMan->pAig, *p, Aig_IthVar(pMan->pAig, v)); }
static inline void Intb_ManAigOrNotVar( Intb_Man_t * pMan, Aig_Obj_t ** p, int v ) { *p = Aig_Or(pMan->pAig, *p, Aig_Not(Aig_IthVar(pMan->pAig, v))); }
static inline void Intb_ManAigMux0( Intb_Man_t * pMan, Aig_Obj_t ** p, Aig_Obj_t ** q, int v){ *p = Aig_Mux(pMan->pAig, Aig_IthVar(pMan->pAig, v), *q, *p); }
static inline void Intb_ManAigMux1( Intb_Man_t * pMan, Aig_Obj_t ** p, Aig_Obj_t ** q, int v){ *p = Aig_Mux(pMan->pAig, Aig_IthVar(pMan->pAig, v), *p, *q); }
// reading/writing the proof for a clause
static inline int Intb_ManProofGet( Intb_Man_t * p, Sto_Cls_t * pCls ) { return p->pProofNums[pCls->Id]; }
static inline void Intb_ManProofSet( Intb_Man_t * p, Sto_Cls_t * pCls, int n ) { p->pProofNums[pCls->Id] = n; }
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Allocate proof manager.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Intb_Man_t * Intb_ManAlloc()
{
Intb_Man_t * p;
// allocate the manager
p = (Intb_Man_t *)ABC_ALLOC( char, sizeof(Intb_Man_t) );
memset( p, 0, sizeof(Intb_Man_t) );
// verification
p->nResLitsAlloc = (1<<16);
p->pResLits = ABC_ALLOC( lit, p->nResLitsAlloc );
// parameters
p->fProofWrite = 0;
p->fProofVerif = 1;
return p;
}
/**Function*************************************************************
Synopsis [Count common variables in the clauses of A and B.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Intb_ManGlobalVars( Intb_Man_t * p )
{
Sto_Cls_t * pClause;
int LargeNum = -100000000;
int Var, nVarsAB, v;
// mark the variable encountered in the clauses of A
Sto_ManForEachClauseRoot( p->pCnf, pClause )
{
if ( !pClause->fA )
break;
for ( v = 0; v < (int)pClause->nLits; v++ )
p->pVarTypes[lit_var(pClause->pLits[v])] = 1;
}
// check variables that appear in clauses of B
nVarsAB = 0;
Sto_ManForEachClauseRoot( p->pCnf, pClause )
{
if ( pClause->fA )
continue;
for ( v = 0; v < (int)pClause->nLits; v++ )
{
Var = lit_var(pClause->pLits[v]);
if ( p->pVarTypes[Var] == 1 ) // var of A
{
// change it into a global variable
nVarsAB++;
p->pVarTypes[Var] = LargeNum;
}
}
}
assert( nVarsAB <= Vec_IntSize(p->vVarsAB) );
// order global variables
nVarsAB = 0;
Vec_IntForEachEntry( p->vVarsAB, Var, v )
p->pVarTypes[Var] = -(1+nVarsAB++);
// check that there is no extra global variables
for ( v = 0; v < p->pCnf->nVars; v++ )
assert( p->pVarTypes[v] != LargeNum );
return nVarsAB;
}
/**Function*************************************************************
Synopsis [Resize proof manager.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Intb_ManResize( Intb_Man_t * p )
{
// check if resizing is needed
if ( p->nVarsAlloc < p->pCnf->nVars )
{
// find the new size
if ( p->nVarsAlloc == 0 )
p->nVarsAlloc = 1;
while ( p->nVarsAlloc < p->pCnf->nVars )
p->nVarsAlloc *= 2;
// resize the arrays
p->pTrail = ABC_REALLOC(lit, p->pTrail, p->nVarsAlloc );
p->pAssigns = ABC_REALLOC(lit, p->pAssigns, p->nVarsAlloc );
p->pSeens = ABC_REALLOC(char, p->pSeens, p->nVarsAlloc );
p->pVarTypes = ABC_REALLOC(int, p->pVarTypes, p->nVarsAlloc );
p->pReasons = ABC_REALLOC(Sto_Cls_t *, p->pReasons, p->nVarsAlloc );
p->pWatches = ABC_REALLOC(Sto_Cls_t *, p->pWatches, p->nVarsAlloc*2 );
}
// clean the ABC_FREE space
memset( p->pAssigns , 0xff, sizeof(lit) * p->pCnf->nVars );
memset( p->pSeens , 0, sizeof(char) * p->pCnf->nVars );
memset( p->pVarTypes, 0, sizeof(int) * p->pCnf->nVars );
memset( p->pReasons , 0, sizeof(Sto_Cls_t *) * p->pCnf->nVars );
memset( p->pWatches , 0, sizeof(Sto_Cls_t *) * p->pCnf->nVars*2 );
// compute the number of common variables
Intb_ManGlobalVars( p );
// check if resizing of clauses is needed
if ( p->nClosAlloc < p->pCnf->nClauses )
{
// find the new size
if ( p->nClosAlloc == 0 )
p->nClosAlloc = 1;
while ( p->nClosAlloc < p->pCnf->nClauses )
p->nClosAlloc *= 2;
// resize the arrays
p->pProofNums = ABC_REALLOC( int, p->pProofNums, p->nClosAlloc );
}
memset( p->pProofNums, 0, sizeof(int) * p->pCnf->nClauses );
// check if resizing of truth tables is needed
if ( p->nIntersAlloc < p->pCnf->nClauses )
{
p->nIntersAlloc = p->pCnf->nClauses;
p->pInters = ABC_REALLOC(Aig_Obj_t *, p->pInters, p->nIntersAlloc );
}
memset( p->pInters, 0, sizeof(Aig_Obj_t *) * p->pCnf->nClauses );
}
/**Function*************************************************************
Synopsis [Deallocate proof manager.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Intb_ManFree( Intb_Man_t * p )
{
/*
printf( "Runtime stats:\n" );
ABC_PRT( "BCP ", p->timeBcp );
ABC_PRT( "Trace ", p->timeTrace );
ABC_PRT( "TOTAL ", p->timeTotal );
*/
ABC_FREE( p->pInters );
ABC_FREE( p->pProofNums );
ABC_FREE( p->pTrail );
ABC_FREE( p->pAssigns );
ABC_FREE( p->pSeens );
ABC_FREE( p->pVarTypes );
ABC_FREE( p->pReasons );
ABC_FREE( p->pWatches );
ABC_FREE( p->pResLits );
ABC_FREE( p );
}
/**Function*************************************************************
Synopsis [Prints the clause.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Intb_ManPrintClause( Intb_Man_t * p, Sto_Cls_t * pClause )
{
int i;
printf( "Clause ID = %d. Proof = %d. {", pClause->Id, Intb_ManProofGet(p, pClause) );
for ( i = 0; i < (int)pClause->nLits; i++ )
printf( " %d", pClause->pLits[i] );
printf( " }\n" );
}
/**Function*************************************************************
Synopsis [Prints the resolvent.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Intb_ManPrintResolvent( lit * pResLits, int nResLits )
{
int i;
printf( "Resolvent: {" );
for ( i = 0; i < nResLits; i++ )
printf( " %d", pResLits[i] );
printf( " }\n" );
}
/**Function*************************************************************
Synopsis [Prints the interpolant for one clause.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Intb_ManPrintInterOne( Intb_Man_t * p, Sto_Cls_t * pClause )
{
printf( "Clause %2d : ", pClause->Id );
// Extra_PrintBinary___( stdout, Intb_ManAigRead(p, pClause), (1 << p->nVarsAB) );
printf( "\n" );
}
/**Function*************************************************************
Synopsis [Adds one clause to the watcher list.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline void Intb_ManWatchClause( Intb_Man_t * p, Sto_Cls_t * pClause, lit Lit )
{
assert( lit_check(Lit, p->pCnf->nVars) );
if ( pClause->pLits[0] == Lit )
pClause->pNext0 = p->pWatches[lit_neg(Lit)];
else
{
assert( pClause->pLits[1] == Lit );
pClause->pNext1 = p->pWatches[lit_neg(Lit)];
}
p->pWatches[lit_neg(Lit)] = pClause;
}
/**Function*************************************************************
Synopsis [Records implication.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline int Intb_ManEnqueue( Intb_Man_t * p, lit Lit, Sto_Cls_t * pReason )
{
int Var = lit_var(Lit);
if ( p->pAssigns[Var] != LIT_UNDEF )
return p->pAssigns[Var] == Lit;
p->pAssigns[Var] = Lit;
p->pReasons[Var] = pReason;
p->pTrail[p->nTrailSize++] = Lit;
//printf( "assigning var %d value %d\n", Var, !lit_sign(Lit) );
return 1;
}
/**Function*************************************************************
Synopsis [Records implication.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline void Intb_ManCancelUntil( Intb_Man_t * p, int Level )
{
lit Lit;
int i, Var;
for ( i = p->nTrailSize - 1; i >= Level; i-- )
{
Lit = p->pTrail[i];
Var = lit_var( Lit );
p->pReasons[Var] = NULL;
p->pAssigns[Var] = LIT_UNDEF;
//printf( "cancelling var %d\n", Var );
}
p->nTrailSize = Level;
}
/**Function*************************************************************
Synopsis [Propagate one assignment.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
static inline Sto_Cls_t * Intb_ManPropagateOne( Intb_Man_t * p, lit Lit )
{
Sto_Cls_t ** ppPrev, * pCur, * pTemp;
lit LitF = lit_neg(Lit);
int i;
// iterate through the literals
ppPrev = p->pWatches + Lit;
for ( pCur = p->pWatches[Lit]; pCur; pCur = *ppPrev )
{
// make sure the false literal is in the second literal of the clause
if ( pCur->pLits[0] == LitF )
{
pCur->pLits[0] = pCur->pLits[1];
pCur->pLits[1] = LitF;
pTemp = pCur->pNext0;
pCur->pNext0 = pCur->pNext1;
pCur->pNext1 = pTemp;
}
assert( pCur->pLits[1] == LitF );
// if the first literal is true, the clause is satisfied
if ( pCur->pLits[0] == p->pAssigns[lit_var(pCur->pLits[0])] )
{
ppPrev = &pCur->pNext1;
continue;
}
// look for a new literal to watch
for ( i = 2; i < (int)pCur->nLits; i++ )
{
// skip the case when the literal is false
if ( lit_neg(pCur->pLits[i]) == p->pAssigns[lit_var(pCur->pLits[i])] )
continue;
// the literal is either true or unassigned - watch it
pCur->pLits[1] = pCur->pLits[i];
pCur->pLits[i] = LitF;
// remove this clause from the watch list of Lit
*ppPrev = pCur->pNext1;
// add this clause to the watch list of pCur->pLits[i] (now it is pCur->pLits[1])
Intb_ManWatchClause( p, pCur, pCur->pLits[1] );
break;
}
if ( i < (int)pCur->nLits ) // found new watch
continue;
// clause is unit - enqueue new implication
if ( Intb_ManEnqueue(p, pCur->pLits[0], pCur) )
{
ppPrev = &pCur->pNext1;
continue;
}
// conflict detected - return the conflict clause
return pCur;
}
return NULL;
}
/**Function*************************************************************
Synopsis [Propagate the current assignments.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Sto_Cls_t * Intb_ManPropagate( Intb_Man_t * p, int Start )
{
Sto_Cls_t * pClause;
int i;
int clk = clock();
for ( i = Start; i < p->nTrailSize; i++ )
{
pClause = Intb_ManPropagateOne( p, p->pTrail[i] );
if ( pClause )
{
p->timeBcp += clock() - clk;
return pClause;
}
}
p->timeBcp += clock() - clk;
return NULL;
}
/**Function*************************************************************
Synopsis [Writes one root clause into a file.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Intb_ManProofWriteOne( Intb_Man_t * p, Sto_Cls_t * pClause )
{
Intb_ManProofSet( p, pClause, ++p->Counter );
if ( p->fProofWrite )
{
int v;
fprintf( p->pFile, "%d", Intb_ManProofGet(p, pClause) );
for ( v = 0; v < (int)pClause->nLits; v++ )
fprintf( p->pFile, " %d", lit_print(pClause->pLits[v]) );
fprintf( p->pFile, " 0 0\n" );
}
}
/**Function*************************************************************
Synopsis [Traces the proof for one clause.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Intb_ManGetGlobalVar( Intb_Man_t * p, int Var )
{
int VarAB;
if ( p->pVarTypes[Var] >= 0 ) // global var
return -1;
VarAB = -p->pVarTypes[Var]-1;
assert( VarAB >= 0 && VarAB < Vec_IntSize(p->vVarsAB) );
return VarAB;
}
/**Function*************************************************************
Synopsis [Traces the proof for one clause.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Intb_ManProofTraceOne( Intb_Man_t * p, Sto_Cls_t * pConflict, Sto_Cls_t * pFinal )
{
Sto_Cls_t * pReason;
int i, v, Var, PrevId;
int fPrint = 0;
int clk = clock();
// collect resolvent literals
if ( p->fProofVerif )
{
assert( (int)pConflict->nLits <= p->nResLitsAlloc );
memcpy( p->pResLits, pConflict->pLits, sizeof(lit) * pConflict->nLits );
p->nResLits = pConflict->nLits;
}
// mark all the variables in the conflict as seen
for ( v = 0; v < (int)pConflict->nLits; v++ )
p->pSeens[lit_var(pConflict->pLits[v])] = 1;
// start the anticedents
// pFinal->pAntis = Vec_PtrAlloc( 32 );
// Vec_PtrPush( pFinal->pAntis, pConflict );
if ( p->pCnf->nClausesA )
Intb_ManAigCopy( p, Intb_ManAigRead(p, pFinal), Intb_ManAigRead(p, pConflict) );
// follow the trail backwards
PrevId = Intb_ManProofGet(p, pConflict);
for ( i = p->nTrailSize - 1; i >= 0; i-- )
{
// skip literals that are not involved
Var = lit_var(p->pTrail[i]);
if ( !p->pSeens[Var] )
continue;
p->pSeens[Var] = 0;
// skip literals of the resulting clause
pReason = p->pReasons[Var];
if ( pReason == NULL )
continue;
assert( p->pTrail[i] == pReason->pLits[0] );
// add the variables to seen
for ( v = 1; v < (int)pReason->nLits; v++ )
p->pSeens[lit_var(pReason->pLits[v])] = 1;
// record the reason clause
assert( Intb_ManProofGet(p, pReason) > 0 );
p->Counter++;
if ( p->fProofWrite )
fprintf( p->pFile, "%d * %d %d 0\n", p->Counter, PrevId, Intb_ManProofGet(p, pReason) );
PrevId = p->Counter;
if ( p->pCnf->nClausesA )
{
if ( p->pVarTypes[Var] == 1 )// || rand() % 10 == 0 ) // var of A
Intb_ManAigOr( p, Intb_ManAigRead(p, pFinal), Intb_ManAigRead(p, pReason) );
else if ( p->pVarTypes[Var] == 0 ) // var of B
Intb_ManAigAnd( p, Intb_ManAigRead(p, pFinal), Intb_ManAigRead(p, pReason) );
else
{
int VarAB = Intb_ManGetGlobalVar(p, Var);
// check that the var is present in the reason
for ( v = 0; v < (int)pReason->nLits; v++ )
if ( lit_var(pReason->pLits[v]) == Var )
break;
assert( v < (int)pReason->nLits );
if ( lit_sign(pReason->pLits[v]) ) // negative polarity
Intb_ManAigMux0( p, Intb_ManAigRead(p, pFinal), Intb_ManAigRead(p, pReason), VarAB );
else
Intb_ManAigMux1( p, Intb_ManAigRead(p, pFinal), Intb_ManAigRead(p, pReason), VarAB );
}
}
// resolve the temporary resolvent with the reason clause
if ( p->fProofVerif )
{
int v1, v2;
if ( fPrint )
Intb_ManPrintResolvent( p->pResLits, p->nResLits );
// check that the var is present in the resolvent
for ( v1 = 0; v1 < p->nResLits; v1++ )
if ( lit_var(p->pResLits[v1]) == Var )
break;
if ( v1 == p->nResLits )
printf( "Recording clause %d: Cannot find variable %d in the temporary resolvent.\n", pFinal->Id, Var );
if ( p->pResLits[v1] != lit_neg(pReason->pLits[0]) )
printf( "Recording clause %d: The resolved variable %d is in the wrong polarity.\n", pFinal->Id, Var );
// remove this variable from the resolvent
assert( lit_var(p->pResLits[v1]) == Var );
p->nResLits--;
for ( ; v1 < p->nResLits; v1++ )
p->pResLits[v1] = p->pResLits[v1+1];
// add variables of the reason clause
for ( v2 = 1; v2 < (int)pReason->nLits; v2++ )
{
for ( v1 = 0; v1 < p->nResLits; v1++ )
if ( lit_var(p->pResLits[v1]) == lit_var(pReason->pLits[v2]) )
break;
// if it is a new variable, add it to the resolvent
if ( v1 == p->nResLits )
{
if ( p->nResLits == p->nResLitsAlloc )
printf( "Recording clause %d: Ran out of space for intermediate resolvent.\n", pFinal->Id );
p->pResLits[ p->nResLits++ ] = pReason->pLits[v2];
continue;
}
// if the variable is the same, the literal should be the same too
if ( p->pResLits[v1] == pReason->pLits[v2] )
continue;
// the literal is different
printf( "Recording clause %d: Trying to resolve the clause with more than one opposite literal.\n", pFinal->Id );
}
}
// Vec_PtrPush( pFinal->pAntis, pReason );
}
// unmark all seen variables
// for ( i = p->nTrailSize - 1; i >= 0; i-- )
// p->pSeens[lit_var(p->pTrail[i])] = 0;
// check that the literals are unmarked
// for ( i = p->nTrailSize - 1; i >= 0; i-- )
// assert( p->pSeens[lit_var(p->pTrail[i])] == 0 );
// use the resulting clause to check the correctness of resolution
if ( p->fProofVerif )
{
int v1, v2;
if ( fPrint )
Intb_ManPrintResolvent( p->pResLits, p->nResLits );
for ( v1 = 0; v1 < p->nResLits; v1++ )
{
for ( v2 = 0; v2 < (int)pFinal->nLits; v2++ )
if ( pFinal->pLits[v2] == p->pResLits[v1] )
break;
if ( v2 < (int)pFinal->nLits )
continue;
break;
}
if ( v1 < p->nResLits )
{
printf( "Recording clause %d: The final resolvent is wrong.\n", pFinal->Id );
Intb_ManPrintClause( p, pConflict );
Intb_ManPrintResolvent( p->pResLits, p->nResLits );
Intb_ManPrintClause( p, pFinal );
}
}
p->timeTrace += clock() - clk;
// return the proof pointer
if ( p->pCnf->nClausesA )
{
// Intb_ManPrintInterOne( p, pFinal );
}
Intb_ManProofSet( p, pFinal, p->Counter );
return p->Counter;
}
/**Function*************************************************************
Synopsis [Records the proof for one clause.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Intb_ManProofRecordOne( Intb_Man_t * p, Sto_Cls_t * pClause )
{
Sto_Cls_t * pConflict;
int i;
// empty clause never ends up there
assert( pClause->nLits > 0 );
if ( pClause->nLits == 0 )
printf( "Error: Empty clause is attempted.\n" );
// add assumptions to the trail
assert( !pClause->fRoot );
assert( p->nTrailSize == p->nRootSize );
for ( i = 0; i < (int)pClause->nLits; i++ )
if ( !Intb_ManEnqueue( p, lit_neg(pClause->pLits[i]), NULL ) )
{
assert( 0 ); // impossible
return 0;
}
// propagate the assumptions
pConflict = Intb_ManPropagate( p, p->nRootSize );
if ( pConflict == NULL )
{
assert( 0 ); // cannot prove
return 0;
}
// construct the proof
Intb_ManProofTraceOne( p, pConflict, pClause );
// undo to the root level
Intb_ManCancelUntil( p, p->nRootSize );
// add large clauses to the watched lists
if ( pClause->nLits > 1 )
{
Intb_ManWatchClause( p, pClause, pClause->pLits[0] );
Intb_ManWatchClause( p, pClause, pClause->pLits[1] );
return 1;
}
assert( pClause->nLits == 1 );
// if the clause proved is unit, add it and propagate
if ( !Intb_ManEnqueue( p, pClause->pLits[0], pClause ) )
{
assert( 0 ); // impossible
return 0;
}
// propagate the assumption
pConflict = Intb_ManPropagate( p, p->nRootSize );
if ( pConflict )
{
// construct the proof
Intb_ManProofTraceOne( p, pConflict, p->pCnf->pEmpty );
// if ( p->fVerbose )
// printf( "Found last conflict after adding unit clause number %d!\n", pClause->Id );
return 0;
}
// update the root level
p->nRootSize = p->nTrailSize;
return 1;
}
/**Function*************************************************************
Synopsis [Propagate the root clauses.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Intb_ManProcessRoots( Intb_Man_t * p )
{
Sto_Cls_t * pClause;
int Counter;
// make sure the root clauses are preceeding the learnt clauses
Counter = 0;
Sto_ManForEachClause( p->pCnf, pClause )
{
assert( (int)pClause->fA == (Counter < (int)p->pCnf->nClausesA) );
assert( (int)pClause->fRoot == (Counter < (int)p->pCnf->nRoots) );
Counter++;
}
assert( p->pCnf->nClauses == Counter );
// make sure the last clause if empty
assert( p->pCnf->pTail->nLits == 0 );
// go through the root unit clauses
p->nTrailSize = 0;
Sto_ManForEachClauseRoot( p->pCnf, pClause )
{
// create watcher lists for the root clauses
if ( pClause->nLits > 1 )
{
Intb_ManWatchClause( p, pClause, pClause->pLits[0] );
Intb_ManWatchClause( p, pClause, pClause->pLits[1] );
}
// empty clause and large clauses
if ( pClause->nLits != 1 )
continue;
// unit clause
assert( lit_check(pClause->pLits[0], p->pCnf->nVars) );
if ( !Intb_ManEnqueue( p, pClause->pLits[0], pClause ) )
{
// detected root level conflict
printf( "Error in Intb_ManProcessRoots(): Detected a root-level conflict too early!\n" );
assert( 0 );
return 0;
}
}
// propagate the root unit clauses
pClause = Intb_ManPropagate( p, 0 );
if ( pClause )
{
// detected root level conflict
Intb_ManProofTraceOne( p, pClause, p->pCnf->pEmpty );
if ( p->fVerbose )
printf( "Found root level conflict!\n" );
return 0;
}
// set the root level
p->nRootSize = p->nTrailSize;
return 1;
}
/**Function*************************************************************
Synopsis [Records the proof.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Intb_ManPrepareInter( Intb_Man_t * p )
{
Sto_Cls_t * pClause;
int Var, VarAB, v;
// set interpolants for root clauses
Sto_ManForEachClauseRoot( p->pCnf, pClause )
{
if ( !pClause->fA ) // clause of B
{
Intb_ManAigFill( p, Intb_ManAigRead(p, pClause) );
// Intb_ManPrintInterOne( p, pClause );
continue;
}
// clause of A
Intb_ManAigClear( p, Intb_ManAigRead(p, pClause) );
for ( v = 0; v < (int)pClause->nLits; v++ )
{
Var = lit_var(pClause->pLits[v]);
if ( p->pVarTypes[Var] < 0 ) // global var
{
VarAB = -p->pVarTypes[Var]-1;
assert( VarAB >= 0 && VarAB < Vec_IntSize(p->vVarsAB) );
if ( lit_sign(pClause->pLits[v]) ) // negative var
Intb_ManAigOrNotVar( p, Intb_ManAigRead(p, pClause), VarAB );
else
Intb_ManAigOrVar( p, Intb_ManAigRead(p, pClause), VarAB );
}
}
// Intb_ManPrintInterOne( p, pClause );
}
}
/**Function*************************************************************
Synopsis [Computes interpolant for the given CNF.]
Description [Takes the interpolation manager, the CNF deriving by the SAT
solver, which includes ClausesA, ClausesB, and learned clauses. Additional
arguments are the vector of variables common to AB and the verbosiness flag.
Returns the AIG manager with a single output, containing the interpolant.]
SideEffects []
SeeAlso []
***********************************************************************/
void * Intb_ManInterpolate( Intb_Man_t * p, Sto_Man_t * pCnf, void * vVarsAB, int fVerbose )
{
Aig_Man_t * pRes;
Aig_Obj_t * pObj;
Sto_Cls_t * pClause;
int RetValue = 1;
int clkTotal = clock();
// check that the CNF makes sense
assert( pCnf->nVars > 0 && pCnf->nClauses > 0 );
p->pCnf = pCnf;
p->fVerbose = fVerbose;
p->vVarsAB = vVarsAB;
p->pAig = pRes = Aig_ManStart( 10000 );
Aig_IthVar( p->pAig, Vec_IntSize(p->vVarsAB) - 1 );
// adjust the manager
Intb_ManResize( p );
// prepare the interpolant computation
Intb_ManPrepareInter( p );
// construct proof for each clause
// start the proof
if ( p->fProofWrite )
{
p->pFile = fopen( "proof.cnf_", "w" );
p->Counter = 0;
}
// write the root clauses
Sto_ManForEachClauseRoot( p->pCnf, pClause )
Intb_ManProofWriteOne( p, pClause );
// propagate root level assignments
if ( Intb_ManProcessRoots( p ) )
{
// if there is no conflict, consider learned clauses
Sto_ManForEachClause( p->pCnf, pClause )
{
if ( pClause->fRoot )
continue;
if ( !Intb_ManProofRecordOne( p, pClause ) )
{
RetValue = 0;
break;
}
}
}
// stop the proof
if ( p->fProofWrite )
{
fclose( p->pFile );
p->pFile = NULL;
}
if ( fVerbose )
{
// ABC_PRT( "Interpo", clock() - clkTotal );
printf( "Vars = %d. Roots = %d. Learned = %d. Resol steps = %d. Ave = %.2f. Mem = %.2f Mb\n",
p->pCnf->nVars, p->pCnf->nRoots, p->pCnf->nClauses-p->pCnf->nRoots, p->Counter,
1.0*(p->Counter-p->pCnf->nRoots)/(p->pCnf->nClauses-p->pCnf->nRoots),
1.0*Sto_ManMemoryReport(p->pCnf)/(1<<20) );
p->timeTotal += clock() - clkTotal;
}
pObj = *Intb_ManAigRead( p, p->pCnf->pTail );
Aig_ObjCreatePo( pRes, pObj );
Aig_ManCleanup( pRes );
p->pAig = NULL;
return pRes;
}
/**Function*************************************************************
Synopsis []
Description []
SideEffects []
SeeAlso []
***********************************************************************/
Aig_Man_t * Intb_ManDeriveClauses( Intb_Man_t * pMan, Sto_Man_t * pCnf, int fClausesA )
{
Aig_Man_t * p;
Aig_Obj_t * pMiter, * pSum, * pLit;
Sto_Cls_t * pClause;
int Var, VarAB, v;
p = Aig_ManStart( 10000 );
pMiter = Aig_ManConst1(p);
Sto_ManForEachClauseRoot( pCnf, pClause )
{
if ( fClausesA ^ pClause->fA ) // clause of B
continue;
// clause of A
pSum = Aig_ManConst0(p);
for ( v = 0; v < (int)pClause->nLits; v++ )
{
Var = lit_var(pClause->pLits[v]);
if ( pMan->pVarTypes[Var] < 0 ) // global var
{
VarAB = -pMan->pVarTypes[Var]-1;
assert( VarAB >= 0 && VarAB < Vec_IntSize(pMan->vVarsAB) );
pLit = Aig_NotCond( Aig_IthVar(p, VarAB), lit_sign(pClause->pLits[v]) );
}
else
pLit = Aig_NotCond( Aig_IthVar(p, Vec_IntSize(pMan->vVarsAB)+1+Var), lit_sign(pClause->pLits[v]) );
pSum = Aig_Or( p, pSum, pLit );
}
pMiter = Aig_And( p, pMiter, pSum );
}
Aig_ObjCreatePo( p, pMiter );
return p;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
|