/**Function********************************************************************
Synopsis [Moves a variable to a specified position.]
Description [If x==x_low, it executes jumping_down. If x==x_high, it
executes jumping_up. This funcion is similar to ddSiftingAux. Returns
1 in case of success; 0 otherwise.]
SideEffects [None]
SeeAlso []
******************************************************************************/
static int
ddJumpingAux(
DdManager * table,
int x,
int x_low,
int x_high,
double temp)
{
Move *move;
Move *moves; /* list of moves */
int initial_size;
int result;
initial_size = table->keys - table->isolated;
#ifdef DD_DEBUG
assert(table->subtables[x].keys > 0);
#endif
moves = NULL;
if (cuddNextLow(table,x) < x_low) {
if (cuddNextHigh(table,x) > x_high) return(1);
moves = ddJumpingDown(table,x,x_high,initial_size);
/* after that point x --> x_high unless early termination */
if (moves == NULL) goto ddJumpingAuxOutOfMem;
/* move backward and stop at best position or accept uphill move */
result = siftBackwardProb(table,moves,initial_size,temp);
if (!result) goto ddJumpingAuxOutOfMem;
} else if (cuddNextHigh(table,x) > x_high) {
moves = ddJumpingUp(table,x,x_low,initial_size);
/* after that point x --> x_low unless early termination */
if (moves == NULL) goto ddJumpingAuxOutOfMem;
/* move backward and stop at best position or accept uphill move */
result = siftBackwardProb(table,moves,initial_size,temp);
if (!result) goto ddJumpingAuxOutOfMem;
} else {
(void) fprintf(table->err,"Unexpected condition in ddJumping\n");
goto ddJumpingAuxOutOfMem;
}
while (moves != NULL) {
move = moves->next;
cuddDeallocNode(table, (DdNode *) moves);
moves = move;
}
return(1);
ddJumpingAuxOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocNode(table, (DdNode *) moves);
moves = move;
}
return(0);
} /* end of ddJumpingAux */
/**Function********************************************************************
Synopsis [This function is for jumping down.]
Description [This is a simplified version of ddSiftingDown. It does not
use lower bounding. Returns the set of moves in case of success; NULL
if memory is full.]
SideEffects [None]
SeeAlso []
******************************************************************************/
static Move *
ddJumpingDown(
DdManager * table,
int x,
int x_high,
int initial_size)
{
Move *moves;
Move *move;
int y;
int size;
int limit_size = initial_size;
moves = NULL;
y = cuddNextHigh(table,x);
while (y <= x_high) {
size = cuddSwapInPlace(table,x,y);
if (size == 0) goto ddJumpingDownOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL) goto ddJumpingDownOutOfMem;
move->x = x;
move->y = y;
move->size = size;
move->next = moves;
moves = move;
if ((double) size > table->maxGrowth * (double) limit_size) {
break;
} else if (size < limit_size) {
limit_size = size;
}
x = y;
y = cuddNextHigh(table,x);
}
return(moves);
ddJumpingDownOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocNode(table, (DdNode *) moves);
moves = move;
}
return(NULL);
} /* end of ddJumpingDown */
/**Function********************************************************************
Synopsis [This function is for exchanging two variables, x and y.]
Description [This is the same funcion as ddSwapping except for
comparison expression. Use probability function, exp(-size_change/temp).]
SideEffects [None]
SeeAlso []
******************************************************************************/
static int
ddExchange(
DdManager * table,
int x,
int y,
double temp)
{
Move *move,*moves;
int tmp;
int x_ref,y_ref;
int x_next,y_next;
int size, result;
int initial_size, limit_size;
x_ref = x;
y_ref = y;
x_next = cuddNextHigh(table,x);
y_next = cuddNextLow(table,y);
moves = NULL;
initial_size = limit_size = table->keys - table->isolated;
for (;;) {
if (x_next == y_next) {
size = cuddSwapInPlace(table,x,x_next);
if (size == 0) goto ddExchangeOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL) goto ddExchangeOutOfMem;
move->x = x;
move->y = x_next;
move->size = size;
move->next = moves;
moves = move;
size = cuddSwapInPlace(table,y_next,y);
if (size == 0) goto ddExchangeOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL) goto ddExchangeOutOfMem;
move->x = y_next;
move->y = y;
move->size = size;
move->next = moves;
moves = move;
size = cuddSwapInPlace(table,x,x_next);
if (size == 0) goto ddExchangeOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL) goto ddExchangeOutOfMem;
move->x = x;
move->y = x_next;
move->size = size;
move->next = moves;
moves = move;
tmp = x;
x = y;
y = tmp;
} else if (x == y_next) {
size = cuddSwapInPlace(table,x,x_next);
if (size == 0) goto ddExchangeOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL) goto ddExchangeOutOfMem;
move->x = x;
move->y = x_next;
move->size = size;
move->next = moves;
moves = move;
tmp = x;
x = y;
y = tmp;
} else {
size = cuddSwapInPlace(table,x,x_next);
if (size == 0) goto ddExchangeOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL) goto ddExchangeOutOfMem;
move->x = x;
move->y = x_next;
move->size = size;
move->next = moves;
moves = move;
size = cuddSwapInPlace(table,y_next,y);
if (size == 0) goto ddExchangeOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL) goto ddExchangeOutOfMem;
move->x = y_next;
move->y = y;
move->size = size;
move->next = moves;
moves = move;
x = x_next;
y = y_next;
}
x_next = cuddNextHigh(table,x);
y_next = cuddNextLow(table,y);
if (x_next > y_ref) break;
if ((double) size > DD_MAX_REORDER_GROWTH * (double) limit_size) {
break;
} else if (size < limit_size) {
limit_size = size;
}
}
if (y_next>=x_ref) {
size = cuddSwapInPlace(table,y_next,y);
if (size == 0) goto ddExchangeOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL) goto ddExchangeOutOfMem;
move->x = y_next;
move->y = y;
move->size = size;
move->next = moves;
moves = move;
}
/* move backward and stop at best position or accept uphill move */
result = siftBackwardProb(table,moves,initial_size,temp);
if (!result) goto ddExchangeOutOfMem;
while (moves != NULL) {
move = moves->next;
cuddDeallocNode(table, (DdNode *) moves);
moves = move;
}
return(1);
ddExchangeOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocNode(table,(DdNode *) moves);
moves = move;
}
return(0);
} /* end of ddExchange */
/**Function********************************************************************
Synopsis [Given xLow <= x <= xHigh moves x up and down between the
boundaries.]
Description [Given xLow <= x <= xHigh moves x up and down between the
boundaries. Finds the best position and does the required changes.
Assumes that x is either an isolated variable, or it is the bottom of
a symmetry group. All symmetries may not have been found, because of
exceeded growth limit. Returns 1 if successful; 0 otherwise.]
SideEffects [None]
******************************************************************************/
static int
ddSymmSiftingConvAux(
DdManager * table,
int x,
int xLow,
int xHigh)
{
Move *move;
Move *moveUp; /* list of up moves */
Move *moveDown; /* list of down moves */
int initialSize;
int result;
int i;
int initGroupSize, finalGroupSize;
initialSize = table->keys - table->isolated;
moveDown = NULL;
moveUp = NULL;
if (x == xLow) { /* Sift down */
#ifdef DD_DEBUG
/* x is bottom of symmetry group */
assert((unsigned) x >= table->subtables[x].next);
#endif
i = table->subtables[x].next;
initGroupSize = x - i + 1;
moveDown = ddSymmSiftingDown(table,x,xHigh);
/* at this point x == xHigh, unless early term */
if (moveDown == MV_OOM) goto ddSymmSiftingConvAuxOutOfMem;
if (moveDown == NULL) return(1);
x = moveDown->y;
i = x;
while ((unsigned) i < table->subtables[i].next) {
i = table->subtables[i].next;
}
#ifdef DD_DEBUG
/* x should be the top of the symmetric group and i the bottom */
assert((unsigned) i >= table->subtables[i].next);
assert((unsigned) x == table->subtables[i].next);
#endif
finalGroupSize = i - x + 1;
if (initGroupSize == finalGroupSize) {
/* No new symmetries detected, go back to best position */
result = ddSymmSiftingBackward(table,moveDown,initialSize);
} else {
initialSize = table->keys - table->isolated;
moveUp = ddSymmSiftingUp(table,x,xLow);
result = ddSymmSiftingBackward(table,moveUp,initialSize);
}
if (!result) goto ddSymmSiftingConvAuxOutOfMem;
} else if (cuddNextHigh(table,x) > xHigh) { /* Sift up */
/* Find top of x's symm group */
while ((unsigned) x < table->subtables[x].next)
x = table->subtables[x].next;
i = x; /* bottom */
x = table->subtables[x].next; /* top */
if (x == xLow) return(1);
initGroupSize = i - x + 1;
moveUp = ddSymmSiftingUp(table,x,xLow);
/* at this point x == xLow, unless early term */
if (moveUp == MV_OOM) goto ddSymmSiftingConvAuxOutOfMem;
if (moveUp == NULL) return(1);
x = moveUp->x;
i = table->subtables[x].next;
#ifdef DD_DEBUG
/* x should be the bottom of the symmetry group and i the top */
assert((unsigned) x >= table->subtables[x].next);
assert((unsigned) i == table->subtables[x].next);
#endif
finalGroupSize = x - i + 1;
if (initGroupSize == finalGroupSize) {
/* No new symmetry groups detected, return to best position */
result = ddSymmSiftingBackward(table,moveUp,initialSize);
} else {
initialSize = table->keys - table->isolated;
moveDown = ddSymmSiftingDown(table,x,xHigh);
result = ddSymmSiftingBackward(table,moveDown,initialSize);
}
if (!result)
goto ddSymmSiftingConvAuxOutOfMem;
} else if ((x - xLow) > (xHigh - x)) { /* must go down first: shorter */
moveDown = ddSymmSiftingDown(table,x,xHigh);
/* at this point x == xHigh, unless early term */
if (moveDown == MV_OOM) goto ddSymmSiftingConvAuxOutOfMem;
if (moveDown != NULL) {
x = moveDown->y;
i = x;
while ((unsigned) i < table->subtables[i].next) {
i = table->subtables[i].next;
}
} else {
while ((unsigned) x < table->subtables[x].next)
x = table->subtables[x].next;
i = x;
x = table->subtables[x].next;
}
#ifdef DD_DEBUG
/* x should be the top of the symmetry group and i the bottom */
assert((unsigned) i >= table->subtables[i].next);
assert((unsigned) x == table->subtables[i].next);
#endif
initGroupSize = i - x + 1;
moveUp = ddSymmSiftingUp(table,x,xLow);
if (moveUp == MV_OOM) goto ddSymmSiftingConvAuxOutOfMem;
if (moveUp != NULL) {
x = moveUp->x;
i = table->subtables[x].next;
} else {
i = x;
while ((unsigned) x < table->subtables[x].next)
x = table->subtables[x].next;
}
#ifdef DD_DEBUG
/* x should be the bottom of the symmetry group and i the top */
assert((unsigned) x >= table->subtables[x].next);
assert((unsigned) i == table->subtables[x].next);
#endif
finalGroupSize = x - i + 1;
if (initGroupSize == finalGroupSize) {
/* No new symmetry groups detected, return to best position */
result = ddSymmSiftingBackward(table,moveUp,initialSize);
} else {
while (moveDown != NULL) {
move = moveDown->next;
cuddDeallocMove(table, moveDown);
moveDown = move;
}
initialSize = table->keys - table->isolated;
moveDown = ddSymmSiftingDown(table,x,xHigh);
result = ddSymmSiftingBackward(table,moveDown,initialSize);
}
if (!result) goto ddSymmSiftingConvAuxOutOfMem;
} else { /* moving up first: shorter */
/* Find top of x's symmetry group */
x = table->subtables[x].next;
moveUp = ddSymmSiftingUp(table,x,xLow);
/* at this point x == xHigh, unless early term */
if (moveUp == MV_OOM) goto ddSymmSiftingConvAuxOutOfMem;
if (moveUp != NULL) {
x = moveUp->x;
i = table->subtables[x].next;
} else {
i = x;
while ((unsigned) x < table->subtables[x].next)
x = table->subtables[x].next;
}
#ifdef DD_DEBUG
/* x is bottom of the symmetry group and i is top */
assert((unsigned) x >= table->subtables[x].next);
assert((unsigned) i == table->subtables[x].next);
#endif
initGroupSize = x - i + 1;
moveDown = ddSymmSiftingDown(table,x,xHigh);
if (moveDown == MV_OOM) goto ddSymmSiftingConvAuxOutOfMem;
if (moveDown != NULL) {
x = moveDown->y;
i = x;
while ((unsigned) i < table->subtables[i].next) {
i = table->subtables[i].next;
}
} else {
i = x;
x = table->subtables[x].next;
}
#ifdef DD_DEBUG
/* x should be the top of the symmetry group and i the bottom */
assert((unsigned) i >= table->subtables[i].next);
assert((unsigned) x == table->subtables[i].next);
#endif
finalGroupSize = i - x + 1;
if (initGroupSize == finalGroupSize) {
/* No new symmetries detected, go back to best position */
result = ddSymmSiftingBackward(table,moveDown,initialSize);
} else {
while (moveUp != NULL) {
move = moveUp->next;
cuddDeallocMove(table, moveUp);
moveUp = move;
}
initialSize = table->keys - table->isolated;
moveUp = ddSymmSiftingUp(table,x,xLow);
result = ddSymmSiftingBackward(table,moveUp,initialSize);
}
if (!result) goto ddSymmSiftingConvAuxOutOfMem;
}
while (moveDown != NULL) {
move = moveDown->next;
cuddDeallocMove(table, moveDown);
moveDown = move;
}
while (moveUp != NULL) {
move = moveUp->next;
cuddDeallocMove(table, moveUp);
moveUp = move;
}
return(1);
ddSymmSiftingConvAuxOutOfMem:
if (moveDown != MV_OOM) {
while (moveDown != NULL) {
move = moveDown->next;
cuddDeallocMove(table, moveDown);
moveDown = move;
}
}
if (moveUp != MV_OOM) {
while (moveUp != NULL) {
move = moveUp->next;
cuddDeallocMove(table, moveUp);
moveUp = move;
}
}
return(0);
} /* end of ddSymmSiftingConvAux */
/**Function********************************************************************
Synopsis [Given xLow <= x <= xHigh moves x up and down between the
boundaries.]
Description [Given xLow <= x <= xHigh moves x up and down between the
boundaries. Finds the best position and does the required changes.
Assumes that x is not part of a symmetry group. Returns 1 if
successful; 0 otherwise.]
SideEffects [None]
******************************************************************************/
static int
ddSymmSiftingAux(
DdManager * table,
int x,
int xLow,
int xHigh)
{
Move *move;
Move *moveUp; /* list of up moves */
Move *moveDown; /* list of down moves */
int initialSize;
int result;
int i;
int topbot; /* index to either top or bottom of symmetry group */
int initGroupSize, finalGroupSize;
#ifdef DD_DEBUG
/* check for previously detected symmetry */
assert(table->subtables[x].next == (unsigned) x);
#endif
initialSize = table->keys - table->isolated;
moveDown = NULL;
moveUp = NULL;
if ((x - xLow) > (xHigh - x)) {
/* Will go down first, unless x == xHigh:
** Look for consecutive symmetries above x.
*/
for (i = x; i > xLow; i--) {
if (!cuddSymmCheck(table,i-1,i))
break;
topbot = table->subtables[i-1].next; /* find top of i-1's group */
table->subtables[i-1].next = i;
table->subtables[x].next = topbot; /* x is bottom of group so its */
/* next is top of i-1's group */
i = topbot + 1; /* add 1 for i--; new i is top of symm group */
}
} else {
/* Will go up first unless x == xlow:
** Look for consecutive symmetries below x.
*/
for (i = x; i < xHigh; i++) {
if (!cuddSymmCheck(table,i,i+1))
break;
/* find bottom of i+1's symm group */
topbot = i + 1;
while ((unsigned) topbot < table->subtables[topbot].next) {
topbot = table->subtables[topbot].next;
}
table->subtables[topbot].next = table->subtables[i].next;
table->subtables[i].next = i + 1;
i = topbot - 1; /* subtract 1 for i++; new i is bottom of group */
}
}
/* Now x may be in the middle of a symmetry group.
** Find bottom of x's symm group.
*/
while ((unsigned) x < table->subtables[x].next)
x = table->subtables[x].next;
if (x == xLow) { /* Sift down */
#ifdef DD_DEBUG
/* x must be a singleton */
assert((unsigned) x == table->subtables[x].next);
#endif
if (x == xHigh) return(1); /* just one variable */
initGroupSize = 1;
moveDown = ddSymmSiftingDown(table,x,xHigh);
/* after this point x --> xHigh, unless early term */
if (moveDown == MV_OOM) goto ddSymmSiftingAuxOutOfMem;
if (moveDown == NULL) return(1);
x = moveDown->y;
/* Find bottom of x's group */
i = x;
while ((unsigned) i < table->subtables[i].next) {
i = table->subtables[i].next;
}
#ifdef DD_DEBUG
/* x should be the top of the symmetry group and i the bottom */
assert((unsigned) i >= table->subtables[i].next);
assert((unsigned) x == table->subtables[i].next);
#endif
finalGroupSize = i - x + 1;
if (initGroupSize == finalGroupSize) {
/* No new symmetry groups detected, return to best position */
result = ddSymmSiftingBackward(table,moveDown,initialSize);
} else {
initialSize = table->keys - table->isolated;
moveUp = ddSymmSiftingUp(table,x,xLow);
result = ddSymmSiftingBackward(table,moveUp,initialSize);
}
if (!result) goto ddSymmSiftingAuxOutOfMem;
} else if (cuddNextHigh(table,x) > xHigh) { /* Sift up */
/* Find top of x's symm group */
i = x; /* bottom */
x = table->subtables[x].next; /* top */
if (x == xLow) return(1); /* just one big group */
initGroupSize = i - x + 1;
moveUp = ddSymmSiftingUp(table,x,xLow);
/* after this point x --> xLow, unless early term */
if (moveUp == MV_OOM) goto ddSymmSiftingAuxOutOfMem;
if (moveUp == NULL) return(1);
x = moveUp->x;
/* Find top of x's group */
i = table->subtables[x].next;
#ifdef DD_DEBUG
/* x should be the bottom of the symmetry group and i the top */
assert((unsigned) x >= table->subtables[x].next);
assert((unsigned) i == table->subtables[x].next);
#endif
finalGroupSize = x - i + 1;
if (initGroupSize == finalGroupSize) {
/* No new symmetry groups detected, return to best position */
result = ddSymmSiftingBackward(table,moveUp,initialSize);
} else {
initialSize = table->keys - table->isolated;
moveDown = ddSymmSiftingDown(table,x,xHigh);
result = ddSymmSiftingBackward(table,moveDown,initialSize);
}
if (!result) goto ddSymmSiftingAuxOutOfMem;
} else if ((x - xLow) > (xHigh - x)) { /* must go down first: shorter */
moveDown = ddSymmSiftingDown(table,x,xHigh);
/* at this point x == xHigh, unless early term */
if (moveDown == MV_OOM) goto ddSymmSiftingAuxOutOfMem;
if (moveDown != NULL) {
x = moveDown->y; /* x is top here */
i = x;
while ((unsigned) i < table->subtables[i].next) {
i = table->subtables[i].next;
}
} else {
i = x;
while ((unsigned) i < table->subtables[i].next) {
i = table->subtables[i].next;
}
x = table->subtables[i].next;
}
#ifdef DD_DEBUG
/* x should be the top of the symmetry group and i the bottom */
assert((unsigned) i >= table->subtables[i].next);
assert((unsigned) x == table->subtables[i].next);
#endif
initGroupSize = i - x + 1;
moveUp = ddSymmSiftingUp(table,x,xLow);
if (moveUp == MV_OOM) goto ddSymmSiftingAuxOutOfMem;
if (moveUp != NULL) {
x = moveUp->x;
i = table->subtables[x].next;
} else {
i = x;
while ((unsigned) x < table->subtables[x].next)
x = table->subtables[x].next;
}
#ifdef DD_DEBUG
/* x should be the bottom of the symmetry group and i the top */
assert((unsigned) x >= table->subtables[x].next);
assert((unsigned) i == table->subtables[x].next);
#endif
finalGroupSize = x - i + 1;
if (initGroupSize == finalGroupSize) {
/* No new symmetry groups detected, return to best position */
result = ddSymmSiftingBackward(table,moveUp,initialSize);
} else {
while (moveDown != NULL) {
move = moveDown->next;
cuddDeallocMove(table, moveDown);
moveDown = move;
}
initialSize = table->keys - table->isolated;
moveDown = ddSymmSiftingDown(table,x,xHigh);
result = ddSymmSiftingBackward(table,moveDown,initialSize);
}
if (!result) goto ddSymmSiftingAuxOutOfMem;
} else { /* moving up first: shorter */
/* Find top of x's symmetry group */
x = table->subtables[x].next;
moveUp = ddSymmSiftingUp(table,x,xLow);
/* at this point x == xHigh, unless early term */
if (moveUp == MV_OOM) goto ddSymmSiftingAuxOutOfMem;
if (moveUp != NULL) {
x = moveUp->x;
i = table->subtables[x].next;
} else {
while ((unsigned) x < table->subtables[x].next)
x = table->subtables[x].next;
i = table->subtables[x].next;
}
#ifdef DD_DEBUG
/* x is bottom of the symmetry group and i is top */
assert((unsigned) x >= table->subtables[x].next);
assert((unsigned) i == table->subtables[x].next);
#endif
initGroupSize = x - i + 1;
moveDown = ddSymmSiftingDown(table,x,xHigh);
if (moveDown == MV_OOM) goto ddSymmSiftingAuxOutOfMem;
if (moveDown != NULL) {
x = moveDown->y;
i = x;
while ((unsigned) i < table->subtables[i].next) {
i = table->subtables[i].next;
}
} else {
i = x;
x = table->subtables[x].next;
}
#ifdef DD_DEBUG
/* x should be the top of the symmetry group and i the bottom */
assert((unsigned) i >= table->subtables[i].next);
assert((unsigned) x == table->subtables[i].next);
#endif
finalGroupSize = i - x + 1;
if (initGroupSize == finalGroupSize) {
/* No new symmetries detected, go back to best position */
result = ddSymmSiftingBackward(table,moveDown,initialSize);
} else {
while (moveUp != NULL) {
move = moveUp->next;
cuddDeallocMove(table, moveUp);
moveUp = move;
}
initialSize = table->keys - table->isolated;
moveUp = ddSymmSiftingUp(table,x,xLow);
result = ddSymmSiftingBackward(table,moveUp,initialSize);
}
if (!result) goto ddSymmSiftingAuxOutOfMem;
}
while (moveDown != NULL) {
move = moveDown->next;
cuddDeallocMove(table, moveDown);
moveDown = move;
}
while (moveUp != NULL) {
move = moveUp->next;
cuddDeallocMove(table, moveUp);
moveUp = move;
}
return(1);
ddSymmSiftingAuxOutOfMem:
if (moveDown != MV_OOM) {
while (moveDown != NULL) {
move = moveDown->next;
cuddDeallocMove(table, moveDown);
moveDown = move;
}
}
if (moveUp != MV_OOM) {
while (moveUp != NULL) {
move = moveUp->next;
cuddDeallocMove(table, moveUp);
moveUp = move;
}
}
return(0);
} /* end of ddSymmSiftingAux */
/**Function********************************************************************
Synopsis [Moves x down until either it reaches the bound (xHigh) or
the size of the DD heap increases too much.]
Description [Moves x down until either it reaches the bound (xHigh)
or the size of the DD heap increases too much. Assumes that x is the
bottom of a symmetry group. Checks x for symmetry to the adjacent
variables. If symmetry is found, the symmetry group of x is merged
with the symmetry group of the other variable. Returns the set of
moves in case of success; MV_OOM if memory is full.]
SideEffects [None]
******************************************************************************/
static Move *
ddSymmSiftingDown(
DdManager * table,
int x,
int xHigh)
{
Move *moves;
Move *move;
int y;
int size;
int limitSize;
int gxtop,gybot;
int R; /* upper bound on node decrease */
int xindex, yindex;
int isolated;
int z;
int zindex;
#ifdef DD_DEBUG
int checkR;
#endif
moves = NULL;
/* Initialize R */
xindex = table->invperm[x];
gxtop = table->subtables[x].next;
limitSize = size = table->keys - table->isolated;
R = 0;
for (z = xHigh; z > gxtop; z--) {
zindex = table->invperm[z];
if (zindex == xindex || cuddTestInteract(table,xindex,zindex)) {
isolated = table->vars[zindex]->ref == 1;
R += table->subtables[z].keys - isolated;
}
}
y = cuddNextHigh(table,x);
while (y <= xHigh && size - R < limitSize) {
#ifdef DD_DEBUG
gxtop = table->subtables[x].next;
checkR = 0;
for (z = xHigh; z > gxtop; z--) {
zindex = table->invperm[z];
if (zindex == xindex || cuddTestInteract(table,xindex,zindex)) {
isolated = table->vars[zindex]->ref == 1;
checkR += table->subtables[z].keys - isolated;
}
}
assert(R == checkR);
#endif
gybot = table->subtables[y].next;
while (table->subtables[gybot].next != (unsigned) y)
gybot = table->subtables[gybot].next;
if (cuddSymmCheck(table,x,y)) {
/* Symmetry found, attach symm groups */
gxtop = table->subtables[x].next;
table->subtables[x].next = y;
table->subtables[gybot].next = gxtop;
} else if (table->subtables[x].next == (unsigned) x &&
table->subtables[y].next == (unsigned) y) {
/* x and y have self symmetry */
/* Update upper bound on node decrease. */
yindex = table->invperm[y];
if (cuddTestInteract(table,xindex,yindex)) {
isolated = table->vars[yindex]->ref == 1;
R -= table->subtables[y].keys - isolated;
}
size = cuddSwapInPlace(table,x,y);
#ifdef DD_DEBUG
assert(table->subtables[x].next == (unsigned) x);
assert(table->subtables[y].next == (unsigned) y);
#endif
if (size == 0) goto ddSymmSiftingDownOutOfMem;
move = (Move *) cuddDynamicAllocNode(table);
if (move == NULL) goto ddSymmSiftingDownOutOfMem;
move->x = x;
move->y = y;
move->size = size;
move->next = moves;
moves = move;
if ((double) size > (double) limitSize * table->maxGrowth)
return(moves);
if (size < limitSize) limitSize = size;
} else { /* Group move */
/* Update upper bound on node decrease: first phase. */
gxtop = table->subtables[x].next;
z = gxtop + 1;
do {
zindex = table->invperm[z];
if (zindex == xindex || cuddTestInteract(table,xindex,zindex)) {
isolated = table->vars[zindex]->ref == 1;
R -= table->subtables[z].keys - isolated;
}
z++;
} while (z <= gybot);
size = ddSymmGroupMove(table,x,y,&moves);
if (size == 0) goto ddSymmSiftingDownOutOfMem;
if ((double) size > (double) limitSize * table->maxGrowth)
return(moves);
if (size < limitSize) limitSize = size;
/* Update upper bound on node decrease: second phase. */
gxtop = table->subtables[gybot].next;
for (z = gxtop + 1; z <= gybot; z++) {
zindex = table->invperm[z];
if (zindex == xindex || cuddTestInteract(table,xindex,zindex)) {
isolated = table->vars[zindex]->ref == 1;
R += table->subtables[z].keys - isolated;
}
}
}
x = gybot;
y = cuddNextHigh(table,x);
}
return(moves);
ddSymmSiftingDownOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocMove(table, moves);
moves = move;
}
return(MV_OOM);
} /* end of ddSymmSiftingDown */
