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
|
/**CFile****************************************************************
FileName [mapperRefs.c]
PackageName [MVSIS 1.3: Multi-valued logic synthesis system.]
Synopsis [Generic technology mapping engine.]
Author [MVSIS Group]
Affiliation [UC Berkeley]
Date [Ver. 2.0. Started - June 1, 2004.]
Revision [$Id: mapperRefs.h,v 1.0 2003/09/08 00:00:00 alanmi Exp $]
***********************************************************************/
#include "mapperInt.h"
ABC_NAMESPACE_IMPL_START
////////////////////////////////////////////////////////////////////////
/// DECLARATIONS ///
////////////////////////////////////////////////////////////////////////
static int Map_NodeIncRefPhaseAct( Map_Node_t * pNode, int fPhase );
static int Map_NodeDecRefPhaseAct( Map_Node_t * pNode, int fPhase );
static float Map_CutRefDeref( Map_Cut_t * pCut, int fPhase, int fReference );
static void Map_MappingSetRefs_rec( Map_Man_t * pMan, Map_Node_t * pNode, Map_Node_t ** ppStore );
////////////////////////////////////////////////////////////////////////
/// FUNCTION DEFINITIONS ///
////////////////////////////////////////////////////////////////////////
/**Function*************************************************************
Synopsis [Reads the actual reference counter of a phase.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
int Map_NodeReadRefPhaseAct( Map_Node_t * pNode, int fPhase )
{
assert( !Map_IsComplement(pNode) );
if ( pNode->pCutBest[0] && pNode->pCutBest[1] ) // both assigned
return pNode->nRefAct[fPhase];
assert( pNode->pCutBest[0] || pNode->pCutBest[1] ); // at least one assigned
return pNode->nRefAct[2];
}
/**Function*************************************************************
Synopsis [Reads the estimated reference counter of a phase.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
float Map_NodeReadRefPhaseEst( Map_Node_t * pNode, int fPhase )
{
assert( !Map_IsComplement(pNode) );
if ( pNode->pCutBest[0] && pNode->pCutBest[1] ) // both assigned
return pNode->nRefEst[fPhase];
assert( pNode->pCutBest[0] || pNode->pCutBest[1] ); // at least one assigned
// return pNode->nRefEst[0] + pNode->nRefEst[1];
return pNode->nRefEst[2];
}
/**Function*************************************************************
Synopsis [Increments the actual reference counter of a phase.]
Description [Returns the old reference counter.]
SideEffects []
SeeAlso []
***********************************************************************/
int Map_NodeIncRefPhaseAct( Map_Node_t * pNode, int fPhase )
{
assert( !Map_IsComplement(pNode) );
if ( pNode->pCutBest[0] && pNode->pCutBest[1] ) // both assigned
return pNode->nRefAct[fPhase]++;
assert( pNode->pCutBest[0] || pNode->pCutBest[1] ); // at least one assigned
return pNode->nRefAct[2]++;
}
/**Function*************************************************************
Synopsis [Decrements the actual reference counter of a phase.]
Description [Returns the new reference counter.]
SideEffects []
SeeAlso []
***********************************************************************/
int Map_NodeDecRefPhaseAct( Map_Node_t * pNode, int fPhase )
{
assert( !Map_IsComplement(pNode) );
if ( pNode->pCutBest[0] && pNode->pCutBest[1] ) // both assigned
return --pNode->nRefAct[fPhase];
assert( pNode->pCutBest[0] || pNode->pCutBest[1] ); // at least one assigned
return --pNode->nRefAct[2];
}
/**Function*************************************************************
Synopsis [Sets the estimated reference counter for the PIs.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Map_MappingEstimateRefsInit( Map_Man_t * p )
{
Map_Node_t * pNode;
int i;
for ( i = 0; i < p->vAnds->nSize; i++ )
{
pNode = p->vAnds->pArray[i];
// pNode->nRefEst[0] = pNode->nRefEst[1] = ((float)pNode->nRefs)*(float)2.0;
pNode->nRefEst[0] = pNode->nRefEst[1] = pNode->nRefEst[2] = ((float)pNode->nRefs);
}
}
/**Function*************************************************************
Synopsis [Sets the estimated reference counter.]
Description [When this procedure is called for the first time,
the reference counter is estimated from the AIG. Otherwise, it is
a linear combination of reference counters in the last two iterations.]
SideEffects []
SeeAlso []
***********************************************************************/
void Map_MappingEstimateRefs( Map_Man_t * p )
{
Map_Node_t * pNode;
int i;
for ( i = 0; i < p->vAnds->nSize; i++ )
{
pNode = p->vAnds->pArray[i];
// pNode->nRefEst[0] = (float)((2.0 * pNode->nRefEst[0] + 1.0 * pNode->nRefAct[0]) / 3.0);
// pNode->nRefEst[1] = (float)((2.0 * pNode->nRefEst[1] + 1.0 * pNode->nRefAct[1]) / 3.0);
// pNode->nRefEst[2] = (float)((2.0 * pNode->nRefEst[2] + 1.0 * pNode->nRefAct[2]) / 3.0);
pNode->nRefEst[0] = (float)((3.0 * pNode->nRefEst[0] + 1.0 * pNode->nRefAct[0]) / 4.0);
pNode->nRefEst[1] = (float)((3.0 * pNode->nRefEst[1] + 1.0 * pNode->nRefAct[1]) / 4.0);
pNode->nRefEst[2] = (float)((3.0 * pNode->nRefEst[2] + 1.0 * pNode->nRefAct[2]) / 4.0);
}
}
/**function*************************************************************
synopsis [Computes the area flow of the cut.]
description [Computes the area flow of the cut if it is implemented using
the best supergate with the best phase.]
sideeffects []
seealso []
***********************************************************************/
float Map_CutGetAreaFlow( Map_Cut_t * pCut, int fPhase )
{
Map_Match_t * pM = pCut->M + fPhase;
Map_Super_t * pSuper = pM->pSuperBest;
unsigned uPhaseTot = pM->uPhaseBest;
Map_Cut_t * pCutFanin;
float aFlowRes, aFlowFanin, nRefs;
int i, fPinPhasePos;
// start the resulting area flow
aFlowRes = pSuper->Area;
// iterate through the leaves
for ( i = 0; i < pCut->nLeaves; i++ )
{
// get the phase of this fanin
fPinPhasePos = ((uPhaseTot & (1 << i)) == 0);
// get the cut implementing this phase of the fanin
pCutFanin = pCut->ppLeaves[i]->pCutBest[fPinPhasePos];
// if the cut is not available, we have to use the opposite phase
if ( pCutFanin == NULL )
{
fPinPhasePos = !fPinPhasePos;
pCutFanin = pCut->ppLeaves[i]->pCutBest[fPinPhasePos];
}
aFlowFanin = pCutFanin->M[fPinPhasePos].AreaFlow; // ignores the area of the interter
// get the fanout count of the cut in the given phase
nRefs = Map_NodeReadRefPhaseEst( pCut->ppLeaves[i], fPinPhasePos );
// if the node does no fanout, assume fanout count equal to 1
if ( nRefs == (float)0.0 )
nRefs = (float)1.0;
// add the area flow due to the fanin
aFlowRes += aFlowFanin / nRefs;
}
pM->AreaFlow = aFlowRes;
return aFlowRes;
}
/**function*************************************************************
synopsis [Computes the exact area associated with the cut.]
description [Assumes that the cut is referenced.]
sideeffects []
seealso []
***********************************************************************/
float Map_CutGetAreaRefed( Map_Cut_t * pCut, int fPhase )
{
float aResult, aResult2;
aResult2 = Map_CutRefDeref( pCut, fPhase, 0 ); // dereference
aResult = Map_CutRefDeref( pCut, fPhase, 1 ); // reference
// assert( aResult == aResult2 );
return aResult;
}
/**function*************************************************************
synopsis [Computes the exact area associated with the cut.]
description []
sideeffects []
seealso []
***********************************************************************/
float Map_CutGetAreaDerefed( Map_Cut_t * pCut, int fPhase )
{
float aResult, aResult2;
aResult2 = Map_CutRefDeref( pCut, fPhase, 1 ); // reference
aResult = Map_CutRefDeref( pCut, fPhase, 0 ); // dereference
// assert( aResult == aResult2 );
return aResult;
}
/**function*************************************************************
synopsis [References the cut.]
description []
sideeffects []
seealso []
***********************************************************************/
float Map_CutRef( Map_Cut_t * pCut, int fPhase )
{
return Map_CutRefDeref( pCut, fPhase, 1 ); // reference
}
/**function*************************************************************
synopsis [Dereferences the cut.]
description []
sideeffects []
seealso []
***********************************************************************/
float Map_CutDeref( Map_Cut_t * pCut, int fPhase )
{
return Map_CutRefDeref( pCut, fPhase, 0 ); // dereference
}
/**function*************************************************************
synopsis [References or dereferences the cut.]
description [This reference part is similar to Cudd_NodeReclaim().
The dereference part is similar to Cudd_RecursiveDeref().]
sideeffects []
seealso []
***********************************************************************/
float Map_CutRefDeref( Map_Cut_t * pCut, int fPhase, int fReference )
{
Map_Node_t * pNodeChild;
Map_Cut_t * pCutChild;
float aArea;
int i, fPhaseChild;
// int nRefs;
// consider the elementary variable
if ( pCut->nLeaves == 1 )
return 0;
// start the area of this cut
aArea = Map_CutGetRootArea( pCut, fPhase );
// go through the children
for ( i = 0; i < pCut->nLeaves; i++ )
{
pNodeChild = pCut->ppLeaves[i];
fPhaseChild = Map_CutGetLeafPhase( pCut, fPhase, i );
// get the reference counter of the child
/*
// this code does not take inverters into account
// the quality of area recovery seems to always be a little worse
if ( fReference )
nRefs = Map_NodeIncRefPhaseAct( pNodeChild, fPhaseChild );
else
nRefs = Map_NodeDecRefPhaseAct( pNodeChild, fPhaseChild );
assert( nRefs >= 0 );
// skip if the child was already reference before
if ( nRefs > 0 )
continue;
*/
if ( fReference )
{
if ( pNodeChild->pCutBest[0] && pNodeChild->pCutBest[1] ) // both phases are present
{
// if this phase of the node is referenced, there is no recursive call
pNodeChild->nRefAct[2]++;
if ( pNodeChild->nRefAct[fPhaseChild]++ > 0 )
continue;
}
else // only one phase is present
{
// inverter should be added if the phase
// (a) has no reference and (b) is implemented using other phase
if ( pNodeChild->nRefAct[fPhaseChild]++ == 0 && pNodeChild->pCutBest[fPhaseChild] == NULL )
aArea += pNodeChild->p->pSuperLib->AreaInv;
// if the node is referenced, there is no recursive call
if ( pNodeChild->nRefAct[2]++ > 0 )
continue;
}
}
else
{
if ( pNodeChild->pCutBest[0] && pNodeChild->pCutBest[1] ) // both phases are present
{
// if this phase of the node is referenced, there is no recursive call
--pNodeChild->nRefAct[2];
if ( --pNodeChild->nRefAct[fPhaseChild] > 0 )
continue;
}
else // only one phase is present
{
// inverter should be added if the phase
// (a) has no reference and (b) is implemented using other phase
if ( --pNodeChild->nRefAct[fPhaseChild] == 0 && pNodeChild->pCutBest[fPhaseChild] == NULL )
aArea += pNodeChild->p->pSuperLib->AreaInv;
// if the node is referenced, there is no recursive call
if ( --pNodeChild->nRefAct[2] > 0 )
continue;
}
assert( pNodeChild->nRefAct[fPhaseChild] >= 0 );
}
// get the child cut
pCutChild = pNodeChild->pCutBest[fPhaseChild];
// if the child does not have this phase mapped, take the opposite phase
if ( pCutChild == NULL )
{
fPhaseChild = !fPhaseChild;
pCutChild = pNodeChild->pCutBest[fPhaseChild];
}
// reference and compute area recursively
aArea += Map_CutRefDeref( pCutChild, fPhaseChild, fReference );
}
return aArea;
}
/**Function*************************************************************
Synopsis [Computes actual reference counters.]
Description [Collects the nodes used in the mapping in array pMan->vMapping.
Nodes are collected in reverse topological order to facilitate the
computation of required times.]
SideEffects []
SeeAlso []
***********************************************************************/
void Map_MappingSetRefs( Map_Man_t * pMan )
{
Map_Node_t * pNode, ** ppStore;
int i, fPhase, LevelMax;
// clean all references
for ( i = 0; i < pMan->vNodesAll->nSize; i++ )
{
pNode = pMan->vNodesAll->pArray[i];
pNode->nRefAct[0] = 0;
pNode->nRefAct[1] = 0;
pNode->nRefAct[2] = 0;
}
// find the largest level of a node
LevelMax = 0;
for ( i = 0; i < pMan->nOutputs; i++ )
if ( LevelMax < (int)Map_Regular(pMan->pOutputs[i])->Level )
LevelMax = Map_Regular(pMan->pOutputs[i])->Level;
// allocate place to store the nodes
ppStore = ABC_ALLOC( Map_Node_t *, LevelMax + 1 );
memset( ppStore, 0, sizeof(Map_Node_t *) * (LevelMax + 1) );
// visit nodes reachable from POs in the DFS order through the best cuts
for ( i = 0; i < pMan->nOutputs; i++ )
{
pNode = pMan->pOutputs[i];
fPhase = !Map_IsComplement(pNode);
if ( !Map_NodeIsConst(pNode) )
Map_MappingSetRefs_rec( pMan, pNode, ppStore );
}
// reconnect the nodes in reverse topological order
pMan->vMapping->nSize = 0;
for ( i = LevelMax; i >= 0; i-- )
for ( pNode = ppStore[i]; pNode; pNode = (Map_Node_t *)pNode->pData0 )
Map_NodeVecPush( pMan->vMapping, pNode );
ABC_FREE( ppStore );
}
/**Function*************************************************************
Synopsis [Recursively computes the DFS ordering of the nodes.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
void Map_MappingSetRefs_rec( Map_Man_t * pMan, Map_Node_t * pNode, Map_Node_t ** ppStore )
{
Map_Cut_t * pCut;
Map_Node_t * pNodeR;
unsigned uPhase;
int i, fPhase, fInvPin;
// get the regular node and its phase
pNodeR = Map_Regular(pNode);
fPhase = !Map_IsComplement(pNode);
// add the node to the list of all visited nodes
if ( pNodeR->nRefAct[2]++ == 0 )
// Map_NodeVecPush( pMan->vMapping, pNodeR );
pNodeR->pData0 = (char *)ppStore[pNodeR->Level], ppStore[pNodeR->Level] = pNodeR;
// quit if the node was already visited in this phase
if ( pNodeR->nRefAct[fPhase]++ )
return;
// quit if this is a PI node
if ( Map_NodeIsVar(pNodeR) )
return;
// get the cut implementing this or opposite polarity
pCut = pNodeR->pCutBest[fPhase];
if ( pCut == NULL )
{
fPhase = !fPhase;
pCut = pNodeR->pCutBest[fPhase];
}
// visit the transitive fanin
uPhase = pCut->M[fPhase].uPhaseBest;
for ( i = 0; i < pCut->nLeaves; i++ )
{
fInvPin = ((uPhase & (1 << i)) > 0);
Map_MappingSetRefs_rec( pMan, Map_NotCond(pCut->ppLeaves[i], fInvPin), ppStore );
}
}
/**Function*************************************************************
Synopsis [Computes the array of mapping.]
Description []
SideEffects []
SeeAlso []
***********************************************************************/
float Map_MappingGetArea( Map_Man_t * pMan, Map_NodeVec_t * vMapping )
{
Map_Node_t * pNode;
float Area;
int i;
Area = 0.0;
for ( i = 0; i < vMapping->nSize; i++ )
{
pNode = vMapping->pArray[i];
// at least one phase has the best cut assigned
assert( pNode->pCutBest[0] != NULL || pNode->pCutBest[1] != NULL );
// at least one phase is used in the mapping
assert( pNode->nRefAct[0] > 0 || pNode->nRefAct[1] > 0 );
// compute the array due to the supergate
if ( Map_NodeIsAnd(pNode) )
{
// count area of the negative phase
if ( pNode->pCutBest[0] && (pNode->nRefAct[0] > 0 || pNode->pCutBest[1] == NULL) )
Area += pNode->pCutBest[0]->M[0].pSuperBest->Area;
// count area of the positive phase
if ( pNode->pCutBest[1] && (pNode->nRefAct[1] > 0 || pNode->pCutBest[0] == NULL) )
Area += pNode->pCutBest[1]->M[1].pSuperBest->Area;
}
// count area of the interver if we need to implement one phase with another phase
if ( (pNode->pCutBest[0] == NULL && pNode->nRefAct[0] > 0) ||
(pNode->pCutBest[1] == NULL && pNode->nRefAct[1] > 0) )
Area += pMan->pSuperLib->AreaInv;
}
// add buffers for each CO driven by a CI
for ( i = 0; i < pMan->nOutputs; i++ )
if ( Map_NodeIsVar(pMan->pOutputs[i]) && !Map_IsComplement(pMan->pOutputs[i]) )
Area += pMan->pSuperLib->AreaBuf;
return Area;
}
////////////////////////////////////////////////////////////////////////
/// END OF FILE ///
////////////////////////////////////////////////////////////////////////
ABC_NAMESPACE_IMPL_END
|
