/**Function********************************************************************
Synopsis [Sifts from treenode->low to treenode->high.]
Description [Sifts from treenode->low to treenode->high. If
croupcheck == CUDD_GROUP_CHECK7, it checks for group creation at the
end of the initial sifting. If a group is created, it is then sifted
again. After sifting one variable, the group that contains it is
dissolved. Returns 1 in case of success; 0 otherwise.]
SideEffects [None]
******************************************************************************/
static int
zddGroupSifting(
DdManager * table,
int lower,
int upper)
{
int *var;
int i,j,x,xInit;
int nvars;
int classes;
int result;
int *sifted;
#ifdef DD_STATS
unsigned previousSize;
#endif
int xindex;
nvars = table->sizeZ;
/* Order variables to sift. */
entry = NULL;
sifted = NULL;
var = ALLOC(int,nvars);
if (var == NULL) {
table->errorCode = CUDD_MEMORY_OUT;
goto zddGroupSiftingOutOfMem;
}
entry = ALLOC(int,nvars);
if (entry == NULL) {
table->errorCode = CUDD_MEMORY_OUT;
goto zddGroupSiftingOutOfMem;
}
sifted = ALLOC(int,nvars);
if (sifted == NULL) {
table->errorCode = CUDD_MEMORY_OUT;
goto zddGroupSiftingOutOfMem;
}
/* Here we consider only one representative for each group. */
for (i = 0, classes = 0; i < nvars; i++) {
sifted[i] = 0;
x = table->permZ[i];
if ((unsigned) x >= table->subtableZ[x].next) {
entry[i] = table->subtableZ[x].keys;
var[classes] = i;
classes++;
}
}
qsort((void *)var,classes,sizeof(int),(int (*)(const void *, const void *))zddUniqueCompareGroup);
/* Now sift. */
for (i = 0; i < ddMin(table->siftMaxVar,classes); i++) {
if (zddTotalNumberSwapping >= table->siftMaxSwap)
break;
xindex = var[i];
if (sifted[xindex] == 1) /* variable already sifted as part of group */
continue;
x = table->permZ[xindex]; /* find current level of this variable */
if (x < lower || x > upper)
continue;
#ifdef DD_STATS
previousSize = table->keysZ;
#endif
#ifdef DD_DEBUG
/* x is bottom of group */
assert((unsigned) x >= table->subtableZ[x].next);
#endif
result = zddGroupSiftingAux(table,x,lower,upper);
if (!result) goto zddGroupSiftingOutOfMem;
#ifdef DD_STATS
if (table->keysZ < previousSize) {
(void) fprintf(table->out,"-");
} else if (table->keysZ > previousSize) {
(void) fprintf(table->out,"+");
} else {
(void) fprintf(table->out,"=");
}
fflush(table->out);
#endif
/* Mark variables in the group just sifted. */
x = table->permZ[xindex];
if ((unsigned) x != table->subtableZ[x].next) {
xInit = x;
do {
j = table->invpermZ[x];
sifted[j] = 1;
x = table->subtableZ[x].next;
} while (x != xInit);
}
#ifdef DD_DEBUG
if (pr > 0) (void) fprintf(table->out,"zddGroupSifting:");
#endif
} /* for */
FREE(sifted);
FREE(var);
FREE(entry);
return(1);
zddGroupSiftingOutOfMem:
if (entry != NULL) FREE(entry);
if (var != NULL) FREE(var);
if (sifted != NULL) FREE(sifted);
return(0);
} /* end of zddGroupSifting */
/**
@brief Sifts from treenode->low to treenode->high.
@details If croupcheck == CUDD_GROUP_CHECK7, it checks for group
creation at the end of the initial sifting. If a group is created,
it is then sifted again. After sifting one variable, the group that
contains it is dissolved.
@return 1 in case of success; 0 otherwise.
@sideeffect None
*/
static int
zddGroupSifting(
DdManager * table,
int lower,
int upper)
{
IndexKey *var;
int i,j,x,xInit;
int nvars;
int classes;
int result;
int *sifted;
#ifdef DD_STATS
unsigned previousSize;
#endif
int xindex;
nvars = table->sizeZ;
/* Order variables to sift. */
sifted = NULL;
var = ALLOC(IndexKey,nvars);
if (var == NULL) {
table->errorCode = CUDD_MEMORY_OUT;
goto zddGroupSiftingOutOfMem;
}
sifted = ALLOC(int,nvars);
if (sifted == NULL) {
table->errorCode = CUDD_MEMORY_OUT;
goto zddGroupSiftingOutOfMem;
}
/* Here we consider only one representative for each group. */
for (i = 0, classes = 0; i < nvars; i++) {
sifted[i] = 0;
x = table->permZ[i];
if ((unsigned) x >= table->subtableZ[x].next) {
var[classes].index = i;
var[classes].keys = table->subtableZ[x].keys;
classes++;
}
}
util_qsort(var,classes,sizeof(IndexKey),zddUniqueCompareGroup);
/* Now sift. */
for (i = 0; i < ddMin(table->siftMaxVar,classes); i++) {
if (table->zddTotalNumberSwapping >= table->siftMaxSwap)
break;
if (util_cpu_time() - table->startTime > table->timeLimit) {
table->autoDynZ = 0; /* prevent further reordering */
break;
}
if (table->terminationCallback != NULL &&
table->terminationCallback(table->tcbArg)) {
table->autoDynZ = 0; /* prevent further reordering */
break;
}
xindex = var[i].index;
if (sifted[xindex] == 1) /* variable already sifted as part of group */
continue;
x = table->permZ[xindex]; /* find current level of this variable */
if (x < lower || x > upper)
continue;
#ifdef DD_STATS
previousSize = table->keysZ;
#endif
#ifdef DD_DEBUG
/* x is bottom of group */
assert((unsigned) x >= table->subtableZ[x].next);
#endif
result = zddGroupSiftingAux(table,x,lower,upper);
if (!result) goto zddGroupSiftingOutOfMem;
#ifdef DD_STATS
if (table->keysZ < previousSize) {
(void) fprintf(table->out,"-");
} else if (table->keysZ > previousSize) {
(void) fprintf(table->out,"+");
} else {
(void) fprintf(table->out,"=");
}
fflush(table->out);
#endif
/* Mark variables in the group just sifted. */
x = table->permZ[xindex];
if ((unsigned) x != table->subtableZ[x].next) {
xInit = x;
do {
j = table->invpermZ[x];
sifted[j] = 1;
x = table->subtableZ[x].next;
} while (x != xInit);
}
#ifdef DD_DEBUG
if (table->enableExtraDebug > 0)
(void) fprintf(table->out,"zddGroupSifting:");
#endif
} /* for */
FREE(sifted);
FREE(var);
return(1);
zddGroupSiftingOutOfMem:
if (var != NULL) FREE(var);
if (sifted != NULL) FREE(sifted);
return(0);
} /* end of zddGroupSifting */
