/**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;
cuddDeallocMove(table, moves);
moves = move;
}
return(NULL);
} /* end of ddJumpingDown */
/**Function********************************************************************
Synopsis [Sifts a variable down and applies the XOR transformation.]
Description [Sifts a variable down. Moves x down until either it
reaches the bound (xHigh) or the size of the ZDD heap increases too
much. Returns the set of moves in case of success; NULL if memory is
full.]
SideEffects [None]
SeeAlso []
******************************************************************************/
static Move *
cuddZddLinearDown(
DdManager * table,
int x,
int xHigh,
Move * prevMoves)
{
Move *moves;
Move *move;
int y;
int size, newsize;
int limitSize;
moves = prevMoves;
limitSize = table->keysZ;
y = cuddZddNextHigh(table, x);
while (y <= xHigh) {
size = cuddZddSwapInPlace(table, x, y);
if (size == 0)
goto cuddZddLinearDownOutOfMem;
newsize = cuddZddLinearInPlace(table, x, y);
if (newsize == 0)
goto cuddZddLinearDownOutOfMem;
move = (Move *) cuddDynamicAllocNode(table);
if (move == NULL)
goto cuddZddLinearDownOutOfMem;
move->x = x;
move->y = y;
move->next = moves;
moves = move;
move->flags = CUDD_SWAP_MOVE;
if (newsize > size) {
/* Undo transformation. The transformation we apply is
** its own inverse. Hence, we just apply the transformation
** again.
*/
newsize = cuddZddLinearInPlace(table,x,y);
if (newsize == 0) goto cuddZddLinearDownOutOfMem;
if (newsize != size) {
(void) fprintf(table->err,"Change in size after identity transformation! From %d to %d\n",size,newsize);
}
} else {
size = newsize;
move->flags = CUDD_LINEAR_TRANSFORM_MOVE;
}
move->size = size;
if ((double)size > (double)limitSize * table->maxGrowth)
break;
if (size < limitSize)
limitSize = size;
x = y;
y = cuddZddNextHigh(table, x);
}
return(moves);
cuddZddLinearDownOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocMove(table, moves);
moves = move;
}
return((Move *) CUDD_OUT_OF_MEM);
} /* end of cuddZddLinearDown */
/**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.
Returns 1 if successful; 0 otherwise.]
SideEffects [None]
SeeAlso []
******************************************************************************/
static int
cuddZddLinearAux(
DdManager * table,
int x,
int xLow,
int xHigh)
{
Move *move;
Move *moveUp; /* list of up move */
Move *moveDown; /* list of down move */
int initial_size;
int result;
initial_size = table->keysZ;
#ifdef DD_DEBUG
assert(table->subtableZ[x].keys > 0);
#endif
moveDown = NULL;
moveUp = NULL;
if (x == xLow) {
moveDown = cuddZddLinearDown(table, x, xHigh, NULL);
/* At this point x --> xHigh. */
if (moveDown == (Move *) CUDD_OUT_OF_MEM)
goto cuddZddLinearAuxOutOfMem;
/* Move backward and stop at best position. */
result = cuddZddLinearBackward(table, initial_size, moveDown);
if (!result)
goto cuddZddLinearAuxOutOfMem;
} else if (x == xHigh) {
moveUp = cuddZddLinearUp(table, x, xLow, NULL);
/* At this point x --> xLow. */
if (moveUp == (Move *) CUDD_OUT_OF_MEM)
goto cuddZddLinearAuxOutOfMem;
/* Move backward and stop at best position. */
result = cuddZddLinearBackward(table, initial_size, moveUp);
if (!result)
goto cuddZddLinearAuxOutOfMem;
} else if ((x - xLow) > (xHigh - x)) { /* must go down first: shorter */
moveDown = cuddZddLinearDown(table, x, xHigh, NULL);
/* At this point x --> xHigh. */
if (moveDown == (Move *) CUDD_OUT_OF_MEM)
goto cuddZddLinearAuxOutOfMem;
moveUp = cuddZddUndoMoves(table,moveDown);
#ifdef DD_DEBUG
assert(moveUp == NULL || moveUp->x == x);
#endif
moveUp = cuddZddLinearUp(table, x, xLow, moveUp);
if (moveUp == (Move *) CUDD_OUT_OF_MEM)
goto cuddZddLinearAuxOutOfMem;
/* Move backward and stop at best position. */
result = cuddZddLinearBackward(table, initial_size, moveUp);
if (!result)
goto cuddZddLinearAuxOutOfMem;
} else {
moveUp = cuddZddLinearUp(table, x, xLow, NULL);
/* At this point x --> xHigh. */
if (moveUp == (Move *) CUDD_OUT_OF_MEM)
goto cuddZddLinearAuxOutOfMem;
/* Then move up. */
moveDown = cuddZddUndoMoves(table,moveUp);
#ifdef DD_DEBUG
assert(moveDown == NULL || moveDown->y == x);
#endif
moveDown = cuddZddLinearDown(table, x, xHigh, moveDown);
if (moveDown == (Move *) CUDD_OUT_OF_MEM)
goto cuddZddLinearAuxOutOfMem;
/* Move backward and stop at best position. */
result = cuddZddLinearBackward(table, initial_size, moveDown);
if (!result)
goto cuddZddLinearAuxOutOfMem;
}
while (moveDown != NULL) {
move = moveDown->next;
cuddDeallocMove(table, moveDown);
moveDown = move;
}
while (moveUp != NULL) {
move = moveUp->next;
cuddDeallocMove(table, moveUp);
moveUp = move;
}
return(1);
cuddZddLinearAuxOutOfMem:
if (moveDown != (Move *) CUDD_OUT_OF_MEM) {
while (moveDown != NULL) {
move = moveDown->next;
cuddDeallocMove(table, moveDown);
moveDown = move;
}
}
if (moveUp != (Move *) CUDD_OUT_OF_MEM) {
while (moveUp != NULL) {
move = moveUp->next;
cuddDeallocMove(table, moveUp);
moveUp = move;
}
}
return(0);
} /* end of cuddZddLinearAux */
/**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;
cuddDeallocMove(table, moves);
moves = move;
}
return(1);
ddExchangeOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocMove(table, 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 [Sifts one variable up and down until it has taken all
positions. Checks for aggregation.]
Description [Sifts one variable up and down until it has taken all
positions. Checks for aggregation. There may be at most two sweeps,
even if the group grows. Assumes that x is either an isolated
variable, or it is the bottom of a group. All groups may not have
been found. The variable being moved is returned to the best position
seen during sifting. Returns 1 in case of success; 0 otherwise.]
SideEffects [None]
******************************************************************************/
static int
zddGroupSiftingAux(
DdManager * table,
int x,
int xLow,
int xHigh)
{
Move *move;
Move *moves; /* list of moves */
int initialSize;
int result;
#ifdef DD_DEBUG
if (pr > 0) (void) fprintf(table->out,"zddGroupSiftingAux from %d to %d\n",xLow,xHigh);
assert((unsigned) x >= table->subtableZ[x].next); /* x is bottom of group */
#endif
initialSize = table->keysZ;
moves = NULL;
if (x == xLow) { /* Sift down */
#ifdef DD_DEBUG
/* x must be a singleton */
assert((unsigned) x == table->subtableZ[x].next);
#endif
if (x == xHigh) return(1); /* just one variable */
if (!zddGroupSiftingDown(table,x,xHigh,&moves))
goto zddGroupSiftingAuxOutOfMem;
/* at this point x == xHigh, unless early term */
/* move backward and stop at best position */
result = zddGroupSiftingBackward(table,moves,initialSize);
#ifdef DD_DEBUG
assert(table->keysZ <= (unsigned) initialSize);
#endif
if (!result) goto zddGroupSiftingAuxOutOfMem;
} else if (cuddZddNextHigh(table,x) > xHigh) { /* Sift up */
#ifdef DD_DEBUG
/* x is bottom of group */
assert((unsigned) x >= table->subtableZ[x].next);
#endif
/* Find top of x's group */
x = table->subtableZ[x].next;
if (!zddGroupSiftingUp(table,x,xLow,&moves))
goto zddGroupSiftingAuxOutOfMem;
/* at this point x == xLow, unless early term */
/* move backward and stop at best position */
result = zddGroupSiftingBackward(table,moves,initialSize);
#ifdef DD_DEBUG
assert(table->keysZ <= (unsigned) initialSize);
#endif
if (!result) goto zddGroupSiftingAuxOutOfMem;
} else if (x - xLow > xHigh - x) { /* must go down first: shorter */
if (!zddGroupSiftingDown(table,x,xHigh,&moves))
goto zddGroupSiftingAuxOutOfMem;
/* at this point x == xHigh, unless early term */
/* Find top of group */
if (moves) {
x = moves->y;
}
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
x = table->subtableZ[x].next;
#ifdef DD_DEBUG
/* x should be the top of a group */
assert((unsigned) x <= table->subtableZ[x].next);
#endif
if (!zddGroupSiftingUp(table,x,xLow,&moves))
goto zddGroupSiftingAuxOutOfMem;
/* move backward and stop at best position */
result = zddGroupSiftingBackward(table,moves,initialSize);
#ifdef DD_DEBUG
assert(table->keysZ <= (unsigned) initialSize);
#endif
if (!result) goto zddGroupSiftingAuxOutOfMem;
} else { /* moving up first: shorter */
/* Find top of x's group */
x = table->subtableZ[x].next;
if (!zddGroupSiftingUp(table,x,xLow,&moves))
goto zddGroupSiftingAuxOutOfMem;
/* at this point x == xHigh, unless early term */
if (moves) {
x = moves->x;
}
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
#ifdef DD_DEBUG
/* x is bottom of a group */
assert((unsigned) x >= table->subtableZ[x].next);
#endif
if (!zddGroupSiftingDown(table,x,xHigh,&moves))
goto zddGroupSiftingAuxOutOfMem;
/* move backward and stop at best position */
result = zddGroupSiftingBackward(table,moves,initialSize);
#ifdef DD_DEBUG
assert(table->keysZ <= (unsigned) initialSize);
#endif
if (!result) goto zddGroupSiftingAuxOutOfMem;
}
while (moves != NULL) {
move = moves->next;
cuddDeallocMove(table, moves);
moves = move;
}
return(1);
zddGroupSiftingAuxOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocMove(table, moves);
moves = move;
}
return(0);
} /* end of zddGroupSiftingAux */
/**Function********************************************************************
Synopsis [Given x_low <= x <= x_high moves x up and down between the
boundaries.]
Description [Given x_low <= x <= x_high 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]
SeeAlso []
******************************************************************************/
static int
cuddZddSymmSiftingAux(
DdManager * table,
int x,
int x_low,
int x_high)
{
Move *move;
Move *move_up; /* list of up move */
Move *move_down; /* list of down move */
int initial_size;
int result;
int i;
int topbot; /* index to either top or bottom of symmetry group */
int init_group_size, final_group_size;
initial_size = table->keysZ;
move_down = NULL;
move_up = NULL;
/* Look for consecutive symmetries above x. */
for (i = x; i > x_low; i--) {
if (!cuddZddSymmCheck(table, i - 1, i))
break;
/* find top of i-1's symmetry */
topbot = table->subtableZ[i - 1].next;
table->subtableZ[i - 1].next = i;
table->subtableZ[x].next = topbot;
/* x is bottom of group so its symmetry is top of i-1's
group */
i = topbot + 1; /* add 1 for i--, new i is top of symm group */
}
/* Look for consecutive symmetries below x. */
for (i = x; i < x_high; i++) {
if (!cuddZddSymmCheck(table, i, i + 1))
break;
/* find bottom of i+1's symm group */
topbot = i + 1;
while ((unsigned) topbot < table->subtableZ[topbot].next)
topbot = table->subtableZ[topbot].next;
table->subtableZ[topbot].next = table->subtableZ[i].next;
table->subtableZ[i].next = i + 1;
i = topbot - 1; /* add 1 for i++,
new i is bottom of symm group */
}
/* Now x maybe in the middle of a symmetry group. */
if (x == x_low) { /* Sift down */
/* Find bottom of x's symm group */
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
i = table->subtableZ[x].next;
init_group_size = x - i + 1;
move_down = cuddZddSymmSifting_down(table, x, x_high,
initial_size);
/* after that point x --> x_high, unless early term */
if (move_down == ZDD_MV_OOM)
goto cuddZddSymmSiftingAuxOutOfMem;
if (move_down == NULL ||
table->subtableZ[move_down->y].next != move_down->y) {
/* symmetry detected may have to make another complete
pass */
if (move_down != NULL)
x = move_down->y;
else
x = table->subtableZ[x].next;
i = x;
while ((unsigned) i < table->subtableZ[i].next) {
i = table->subtableZ[i].next;
}
final_group_size = i - x + 1;
if (init_group_size == final_group_size) {
/* No new symmetry groups detected,
return to best position */
result = cuddZddSymmSiftingBackward(table,
move_down, initial_size);
}
else {
initial_size = table->keysZ;
move_up = cuddZddSymmSifting_up(table, x, x_low,
initial_size);
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
}
}
else {
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
/* move backward and stop at best position */
}
if (!result)
goto cuddZddSymmSiftingAuxOutOfMem;
}
else if (x == x_high) { /* Sift up */
/* Find top of x's symm group */
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
x = table->subtableZ[x].next;
i = x;
while ((unsigned) i < table->subtableZ[i].next) {
i = table->subtableZ[i].next;
}
init_group_size = i - x + 1;
move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size);
/* after that point x --> x_low, unless early term */
if (move_up == ZDD_MV_OOM)
goto cuddZddSymmSiftingAuxOutOfMem;
if (move_up == NULL ||
table->subtableZ[move_up->x].next != move_up->x) {
/* symmetry detected may have to make another complete
pass */
if (move_up != NULL)
x = move_up->x;
else {
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
}
i = table->subtableZ[x].next;
final_group_size = x - i + 1;
if (init_group_size == final_group_size) {
/* No new symmetry groups detected,
return to best position */
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
}
else {
initial_size = table->keysZ;
move_down = cuddZddSymmSifting_down(table, x, x_high,
initial_size);
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
}
}
else {
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
/* move backward and stop at best position */
}
if (!result)
goto cuddZddSymmSiftingAuxOutOfMem;
}
else if ((x - x_low) > (x_high - x)) { /* must go down first:
shorter */
/* Find bottom of x's symm group */
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
move_down = cuddZddSymmSifting_down(table, x, x_high,
initial_size);
/* after that point x --> x_high, unless early term */
if (move_down == ZDD_MV_OOM)
goto cuddZddSymmSiftingAuxOutOfMem;
if (move_down != NULL) {
x = move_down->y;
}
else {
x = table->subtableZ[x].next;
}
i = x;
while ((unsigned) i < table->subtableZ[i].next) {
i = table->subtableZ[i].next;
}
init_group_size = i - x + 1;
move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size);
if (move_up == ZDD_MV_OOM)
goto cuddZddSymmSiftingAuxOutOfMem;
if (move_up == NULL ||
table->subtableZ[move_up->x].next != move_up->x) {
/* symmetry detected may have to make another complete
pass */
if (move_up != NULL) {
x = move_up->x;
}
else {
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
}
i = table->subtableZ[x].next;
final_group_size = x - i + 1;
if (init_group_size == final_group_size) {
/* No new symmetry groups detected,
return to best position */
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
}
else {
while (move_down != NULL) {
move = move_down->next;
cuddDeallocMove(table, move_down);
move_down = move;
}
initial_size = table->keysZ;
move_down = cuddZddSymmSifting_down(table, x, x_high,
initial_size);
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
}
}
else {
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
/* move backward and stop at best position */
}
if (!result)
goto cuddZddSymmSiftingAuxOutOfMem;
}
else { /* moving up first:shorter */
/* Find top of x's symmetry group */
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
x = table->subtableZ[x].next;
move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size);
/* after that point x --> x_high, unless early term */
if (move_up == ZDD_MV_OOM)
goto cuddZddSymmSiftingAuxOutOfMem;
if (move_up != NULL) {
x = move_up->x;
}
else {
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
}
i = table->subtableZ[x].next;
init_group_size = x - i + 1;
move_down = cuddZddSymmSifting_down(table, x, x_high,
initial_size);
if (move_down == ZDD_MV_OOM)
goto cuddZddSymmSiftingAuxOutOfMem;
if (move_down == NULL ||
table->subtableZ[move_down->y].next != move_down->y) {
/* symmetry detected may have to make another complete
pass */
if (move_down != NULL) {
x = move_down->y;
}
else {
x = table->subtableZ[x].next;
}
i = x;
while ((unsigned) i < table->subtableZ[i].next) {
i = table->subtableZ[i].next;
}
final_group_size = i - x + 1;
if (init_group_size == final_group_size) {
/* No new symmetries detected,
go back to best position */
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
}
else {
while (move_up != NULL) {
move = move_up->next;
cuddDeallocMove(table, move_up);
move_up = move;
}
initial_size = table->keysZ;
move_up = cuddZddSymmSifting_up(table, x, x_low,
initial_size);
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
}
}
else {
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
/* move backward and stop at best position */
}
if (!result)
goto cuddZddSymmSiftingAuxOutOfMem;
}
while (move_down != NULL) {
move = move_down->next;
cuddDeallocMove(table, move_down);
move_down = move;
}
while (move_up != NULL) {
move = move_up->next;
cuddDeallocMove(table, move_up);
move_up = move;
}
return(1);
cuddZddSymmSiftingAuxOutOfMem:
if (move_down != ZDD_MV_OOM) {
while (move_down != NULL) {
move = move_down->next;
cuddDeallocMove(table, move_down);
move_down = move;
}
}
if (move_up != ZDD_MV_OOM) {
while (move_up != NULL) {
move = move_up->next;
cuddDeallocMove(table, move_up);
move_up = move;
}
}
return(0);
} /* end of cuddZddSymmSiftingAux */
/**Function********************************************************************
Synopsis [Reorders variables by a sequence of (non-adjacent) swaps.]
Description [Implementation of Plessier's algorithm that reorders
variables by a sequence of (non-adjacent) swaps.
<ol>
<li> Select two variables (RANDOM or HEURISTIC).
<li> Permute these variables.
<li> If the nodes have decreased accept the permutation.
<li> Otherwise reconstruct the original heap.
<li> Loop.
</ol>
Returns 1 in case of success; 0 otherwise.]
SideEffects [None]
SeeAlso []
******************************************************************************/
int
cuddZddSwapping(
DdManager * table,
int lower,
int upper,
Cudd_ReorderingType heuristic)
{
int i, j;
int max, keys;
int nvars;
int x, y;
int iterate;
int previousSize;
Move *moves, *move;
int pivot;
int modulo;
int result;
#ifdef DD_DEBUG
/* Sanity check */
assert(lower >= 0 && upper < table->sizeZ && lower <= upper);
#endif
nvars = upper - lower + 1;
iterate = nvars;
for (i = 0; i < iterate; i++) {
if (heuristic == CUDD_REORDER_RANDOM_PIVOT) {
/* Find pivot <= id with maximum keys. */
for (max = -1, j = lower; j <= upper; j++) {
if ((keys = table->subtableZ[j].keys) > max) {
max = keys;
pivot = j;
}
}
modulo = upper - pivot;
if (modulo == 0) {
y = pivot; /* y = nvars-1 */
} else {
/* y = random # from {pivot+1 .. nvars-1} */
y = pivot + 1 + (int) (Cudd_Random() % modulo);
}
modulo = pivot - lower - 1;
if (modulo < 1) { /* if pivot = 1 or 0 */
x = lower;
} else {
do { /* x = random # from {0 .. pivot-2} */
x = (int) Cudd_Random() % modulo;
} while (x == y);
/* Is this condition really needed, since x and y
are in regions separated by pivot? */
}
} else {
x = (int) (Cudd_Random() % nvars) + lower;
do {
y = (int) (Cudd_Random() % nvars) + lower;
} while (x == y);
}
previousSize = table->keysZ;
moves = zddSwapAny(table, x, y);
if (moves == NULL)
goto cuddZddSwappingOutOfMem;
result = cuddZddSiftingBackward(table, moves, previousSize);
if (!result)
goto cuddZddSwappingOutOfMem;
while (moves != NULL) {
move = moves->next;
cuddDeallocMove(table, moves);
moves = move;
}
#ifdef DD_STATS
if (table->keysZ < (unsigned) previousSize) {
(void) fprintf(table->out,"-");
} else if (table->keysZ > (unsigned) previousSize) {
(void) fprintf(table->out,"+"); /* should never happen */
} else {
(void) fprintf(table->out,"=");
}
fflush(table->out);
#endif
}
return(1);
cuddZddSwappingOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocMove(table, moves);
moves = move;
}
return(0);
} /* end of cuddZddSwapping */
/**Function********************************************************************
Synopsis [Swaps any two variables.]
Description [Swaps any two variables. Returns the set of moves.]
SideEffects [None]
SeeAlso []
******************************************************************************/
static Move *
zddSwapAny(
DdManager * table,
int x,
int y)
{
Move *move, *moves;
int tmp, size;
int x_ref, y_ref;
int x_next, y_next;
int limit_size;
if (x > y) { /* make x precede y */
tmp = x; x = y; y = tmp;
}
x_ref = x; y_ref = y;
x_next = cuddZddNextHigh(table, x);
y_next = cuddZddNextLow(table, y);
moves = NULL;
limit_size = table->keysZ;
for (;;) {
if (x_next == y_next) { /* x < x_next = y_next < y */
size = cuddZddSwapInPlace(table, x, x_next);
if (size == 0)
goto zddSwapAnyOutOfMem;
move = (Move *) cuddDynamicAllocNode(table);
if (move == NULL)
goto zddSwapAnyOutOfMem;
move->x = x;
move->y = x_next;
move->size = size;
move->next = moves;
moves = move;
size = cuddZddSwapInPlace(table, y_next, y);
if (size == 0)
goto zddSwapAnyOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL)
goto zddSwapAnyOutOfMem;
move->x = y_next;
move->y = y;
move->size = size;
move->next = moves;
moves = move;
size = cuddZddSwapInPlace(table, x, x_next);
if (size == 0)
goto zddSwapAnyOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL)
goto zddSwapAnyOutOfMem;
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) { /* x = y_next < y = x_next */
size = cuddZddSwapInPlace(table, x, x_next);
if (size == 0)
goto zddSwapAnyOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL)
goto zddSwapAnyOutOfMem;
move->x = x;
move->y = x_next;
move->size = size;
move->next = moves;
moves = move;
tmp = x; x = y; y = tmp;
} else {
size = cuddZddSwapInPlace(table, x, x_next);
if (size == 0)
goto zddSwapAnyOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL)
goto zddSwapAnyOutOfMem;
move->x = x;
move->y = x_next;
move->size = size;
move->next = moves;
moves = move;
size = cuddZddSwapInPlace(table, y_next, y);
if (size == 0)
goto zddSwapAnyOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL)
goto zddSwapAnyOutOfMem;
move->x = y_next;
move->y = y;
move->size = size;
move->next = moves;
moves = move;
x = x_next; y = y_next;
}
x_next = cuddZddNextHigh(table, x);
y_next = cuddZddNextLow(table, y);
if (x_next > y_ref)
break; /* if x == y_ref */
if ((double) size > table->maxGrowth * (double) limit_size)
break;
if (size < limit_size)
limit_size = size;
}
if (y_next >= x_ref) {
size = cuddZddSwapInPlace(table, y_next, y);
if (size == 0)
goto zddSwapAnyOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL)
goto zddSwapAnyOutOfMem;
move->x = y_next;
move->y = y;
move->size = size;
move->next = moves;
moves = move;
}
return(moves);
zddSwapAnyOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocMove(table, moves);
moves = move;
}
return(NULL);
} /* end of zddSwapAny */
/**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.
Returns 1 if successful; 0 otherwise.]
SideEffects [None]
SeeAlso []
******************************************************************************/
static int
cuddZddSiftingAux(
DdManager * table,
int x,
int x_low,
int x_high)
{
Move *move;
Move *moveUp; /* list of up move */
Move *moveDown; /* list of down move */
int initial_size;
int result;
initial_size = table->keysZ;
#ifdef DD_DEBUG
assert(table->subtableZ[x].keys > 0);
#endif
moveDown = NULL;
moveUp = NULL;
if (x == x_low) {
moveDown = cuddZddSiftingDown(table, x, x_high, initial_size);
/* after that point x --> x_high */
if (moveDown == NULL)
goto cuddZddSiftingAuxOutOfMem;
result = cuddZddSiftingBackward(table, moveDown,
initial_size);
/* move backward and stop at best position */
if (!result)
goto cuddZddSiftingAuxOutOfMem;
}
else if (x == x_high) {
moveUp = cuddZddSiftingUp(table, x, x_low, initial_size);
/* after that point x --> x_low */
if (moveUp == NULL)
goto cuddZddSiftingAuxOutOfMem;
result = cuddZddSiftingBackward(table, moveUp, initial_size);
/* move backward and stop at best position */
if (!result)
goto cuddZddSiftingAuxOutOfMem;
}
else if ((x - x_low) > (x_high - x)) {
/* must go down first:shorter */
moveDown = cuddZddSiftingDown(table, x, x_high, initial_size);
/* after that point x --> x_high */
if (moveDown == NULL)
goto cuddZddSiftingAuxOutOfMem;
moveUp = cuddZddSiftingUp(table, moveDown->y, x_low,
initial_size);
if (moveUp == NULL)
goto cuddZddSiftingAuxOutOfMem;
result = cuddZddSiftingBackward(table, moveUp, initial_size);
/* move backward and stop at best position */
if (!result)
goto cuddZddSiftingAuxOutOfMem;
}
else {
moveUp = cuddZddSiftingUp(table, x, x_low, initial_size);
/* after that point x --> x_high */
if (moveUp == NULL)
goto cuddZddSiftingAuxOutOfMem;
moveDown = cuddZddSiftingDown(table, moveUp->x, x_high,
initial_size);
/* then move up */
if (moveDown == NULL)
goto cuddZddSiftingAuxOutOfMem;
result = cuddZddSiftingBackward(table, moveDown,
initial_size);
/* move backward and stop at best position */
if (!result)
goto cuddZddSiftingAuxOutOfMem;
}
while (moveDown != NULL) {
move = moveDown->next;
cuddDeallocMove(table, moveDown);
moveDown = move;
}
while (moveUp != NULL) {
move = moveUp->next;
cuddDeallocMove(table, moveUp);
moveUp = move;
}
return(1);
cuddZddSiftingAuxOutOfMem:
while (moveDown != NULL) {
move = moveDown->next;
cuddDeallocMove(table, moveDown);
moveDown = move;
}
while (moveUp != NULL) {
move = moveUp->next;
cuddDeallocMove(table, moveUp);
moveUp = move;
}
return(0);
} /* end of cuddZddSiftingAux */
/**Function********************************************************************
Synopsis [Sifts down a variable until it reaches position xHigh.]
Description [Sifts down a variable until it reaches position xHigh.
Assumes that x is the bottom of a group (or a singleton). Records
all the moves. Returns 1 in case of success; 0 otherwise.]
SideEffects [None]
******************************************************************************/
static int
zddGroupSiftingDown(
DdManager * table,
int x,
int xHigh,
Move ** moves)
{
Move *move;
int y;
int size;
int limitSize;
int gybot;
/* Initialize R */
limitSize = size = table->keysZ;
y = cuddZddNextHigh(table,x);
while (y <= xHigh) {
/* Find bottom of y group. */
gybot = table->subtableZ[y].next;
while (table->subtableZ[gybot].next != (unsigned) y)
gybot = table->subtableZ[gybot].next;
if (table->subtableZ[x].next == (unsigned) x &&
table->subtableZ[y].next == (unsigned) y) {
/* x and y are self groups */
size = cuddZddSwapInPlace(table,x,y);
#ifdef DD_DEBUG
assert(table->subtableZ[x].next == (unsigned) x);
assert(table->subtableZ[y].next == (unsigned) y);
#endif
if (size == 0) goto zddGroupSiftingDownOutOfMem;
/* Record move. */
move = (Move *) cuddDynamicAllocNode(table);
if (move == NULL) goto zddGroupSiftingDownOutOfMem;
move->x = x;
move->y = y;
move->flags = MTR_DEFAULT;
move->size = size;
move->next = *moves;
*moves = move;
#ifdef DD_DEBUG
if (pr > 0) (void) fprintf(table->out,"zddGroupSiftingDown (2 single groups):\n");
#endif
if ((double) size > (double) limitSize * table->maxGrowth)
return(1);
if (size < limitSize) limitSize = size;
x = y;
y = cuddZddNextHigh(table,x);
} else { /* Group move */
size = zddGroupMove(table,x,y,moves);
if (size == 0) goto zddGroupSiftingDownOutOfMem;
if ((double) size > (double) limitSize * table->maxGrowth)
return(1);
if (size < limitSize) limitSize = size;
}
x = gybot;
y = cuddZddNextHigh(table,x);
}
return(1);
zddGroupSiftingDownOutOfMem:
while (*moves != NULL) {
move = (*moves)->next;
cuddDeallocMove(table, *moves);
*moves = move;
}
return(0);
} /* end of zddGroupSiftingDown */
/**Function********************************************************************
Synopsis [Sifts up a variable until either it reaches position xLow
or the size of the DD heap increases too much.]
Description [Sifts up a variable until either it reaches position
xLow or the size of the DD heap increases too much. Assumes that y is
the top of a group (or a singleton). Checks y for aggregation to the
adjacent variables. Records all the moves that are appended to the
list of moves received as input and returned as a side effect.
Returns 1 in case of success; 0 otherwise.]
SideEffects [None]
******************************************************************************/
static int
zddGroupSiftingUp(
DdManager * table,
int y,
int xLow,
Move ** moves)
{
Move *move;
int x;
int size;
int gxtop;
int limitSize;
limitSize = table->keysZ;
x = cuddZddNextLow(table,y);
while (x >= xLow) {
gxtop = table->subtableZ[x].next;
if (table->subtableZ[x].next == (unsigned) x &&
table->subtableZ[y].next == (unsigned) y) {
/* x and y are self groups */
size = cuddZddSwapInPlace(table,x,y);
#ifdef DD_DEBUG
assert(table->subtableZ[x].next == (unsigned) x);
assert(table->subtableZ[y].next == (unsigned) y);
#endif
if (size == 0) goto zddGroupSiftingUpOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL) goto zddGroupSiftingUpOutOfMem;
move->x = x;
move->y = y;
move->flags = MTR_DEFAULT;
move->size = size;
move->next = *moves;
*moves = move;
#ifdef DD_DEBUG
if (pr > 0) (void) fprintf(table->out,"zddGroupSiftingUp (2 single groups):\n");
#endif
if ((double) size > (double) limitSize * table->maxGrowth)
return(1);
if (size < limitSize) limitSize = size;
} else { /* group move */
size = zddGroupMove(table,x,y,moves);
if (size == 0) goto zddGroupSiftingUpOutOfMem;
if ((double) size > (double) limitSize * table->maxGrowth)
return(1);
if (size < limitSize) limitSize = size;
}
y = gxtop;
x = cuddZddNextLow(table,y);
}
return(1);
zddGroupSiftingUpOutOfMem:
while (*moves != NULL) {
move = (*moves)->next;
cuddDeallocMove(table, *moves);
*moves = move;
}
return(0);
} /* end of zddGroupSiftingUp */
/**Function********************************************************************
Synopsis [Moves x down until either it reaches the bound (x_high) or
the size of the ZDD heap increases too much.]
Description [Moves x down until either it reaches the bound (x_high)
or the size of the ZDD 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; ZDD_MV_OOM if memory is full.]
SideEffects [None]
SeeAlso []
******************************************************************************/
static Move *
cuddZddSymmSifting_down(
DdManager * table,
int x,
int x_high,
int initial_size)
{
Move *moves;
Move *move;
int y;
int size;
int limit_size = initial_size;
int i, gxtop, gybot;
moves = NULL;
y = cuddZddNextHigh(table, x);
while (y <= x_high) {
gybot = table->subtableZ[y].next;
while (table->subtableZ[gybot].next != (unsigned) y)
gybot = table->subtableZ[gybot].next;
if (cuddZddSymmCheck(table, x, y)) {
/* Symmetry found, attach symm groups */
gxtop = table->subtableZ[x].next;
table->subtableZ[x].next = y;
i = table->subtableZ[y].next;
while (table->subtableZ[i].next != (unsigned) y)
i = table->subtableZ[i].next;
table->subtableZ[i].next = gxtop;
}
else if ((table->subtableZ[x].next == (unsigned) x) &&
(table->subtableZ[y].next == (unsigned) y)) {
/* x and y have self symmetry */
size = cuddZddSwapInPlace(table, x, y);
if (size == 0)
goto cuddZddSymmSifting_downOutOfMem;
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL)
goto cuddZddSymmSifting_downOutOfMem;
move->x = x;
move->y = y;
move->size = size;
move->next = moves;
moves = move;
if ((double)size >
(double)limit_size * table->maxGrowth)
return(moves);
if (size < limit_size)
limit_size = size;
x = y;
y = cuddZddNextHigh(table, x);
}
else { /* Group move */
size = zdd_group_move(table, x, y, &moves);
if ((double)size >
(double)limit_size * table->maxGrowth)
return(moves);
if (size < limit_size)
limit_size = size;
}
x = gybot;
y = cuddZddNextHigh(table, x);
}
return(moves);
cuddZddSymmSifting_downOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocMove(table, moves);
moves = move;
}
return(ZDD_MV_OOM);
} /* end of cuddZddSymmSifting_down */
/**Function********************************************************************
Synopsis [Moves x up until either it reaches the bound (xLow) or
the size of the DD heap increases too much.]
Description [Moves x up until either it reaches the bound (xLow) or
the size of the DD heap increases too much. Assumes that x is the top
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 *
ddSymmSiftingUp(
DdManager * table,
int y,
int xLow)
{
Move *moves;
Move *move;
int x;
int size;
int i;
int gxtop,gybot;
int limitSize;
int xindex, yindex;
int zindex;
int z;
int isolated;
int L; /* lower bound on DD size */
#ifdef DD_DEBUG
int checkL;
#endif
moves = NULL;
yindex = table->invperm[y];
/* Initialize the lower bound.
** The part of the DD below the bottom of y' group will not change.
** The part of the DD above y that does not interact with y will not
** change. The rest may vanish in the best case, except for
** the nodes at level xLow, which will not vanish, regardless.
*/
limitSize = L = table->keys - table->isolated;
gybot = y;
while ((unsigned) gybot < table->subtables[gybot].next)
gybot = table->subtables[gybot].next;
for (z = xLow + 1; z <= gybot; z++) {
zindex = table->invperm[z];
if (zindex == yindex || cuddTestInteract(table,zindex,yindex)) {
isolated = table->vars[zindex]->ref == 1;
L -= table->subtables[z].keys - isolated;
}
}
x = cuddNextLow(table,y);
while (x >= xLow && L <= limitSize) {
#ifdef DD_DEBUG
gybot = y;
while ((unsigned) gybot < table->subtables[gybot].next)
gybot = table->subtables[gybot].next;
checkL = table->keys - table->isolated;
for (z = xLow + 1; z <= gybot; z++) {
zindex = table->invperm[z];
if (zindex == yindex || cuddTestInteract(table,zindex,yindex)) {
isolated = table->vars[zindex]->ref == 1;
checkL -= table->subtables[z].keys - isolated;
}
}
assert(L == checkL);
#endif
gxtop = table->subtables[x].next;
if (cuddSymmCheck(table,x,y)) {
/* Symmetry found, attach symm groups */
table->subtables[x].next = y;
i = table->subtables[y].next;
while (table->subtables[i].next != (unsigned) y)
i = table->subtables[i].next;
table->subtables[i].next = gxtop;
} else if (table->subtables[x].next == (unsigned) x &&
table->subtables[y].next == (unsigned) y) {
/* x and y have self symmetry */
xindex = table->invperm[x];
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 ddSymmSiftingUpOutOfMem;
/* Update the lower bound. */
if (cuddTestInteract(table,xindex,yindex)) {
isolated = table->vars[xindex]->ref == 1;
L += table->subtables[y].keys - isolated;
}
move = (Move *) cuddDynamicAllocNode(table);
if (move == NULL) goto ddSymmSiftingUpOutOfMem;
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 */
size = ddSymmGroupMove(table,x,y,&moves);
if (size == 0) goto ddSymmSiftingUpOutOfMem;
/* Update the lower bound. */
z = moves->y;
do {
zindex = table->invperm[z];
if (cuddTestInteract(table,zindex,yindex)) {
isolated = table->vars[zindex]->ref == 1;
L += table->subtables[z].keys - isolated;
}
z = table->subtables[z].next;
} while (z != (int) moves->y);
if ((double) size > (double) limitSize * table->maxGrowth)
return(moves);
if (size < limitSize) limitSize = size;
}
y = gxtop;
x = cuddNextLow(table,y);
}
return(moves);
ddSymmSiftingUpOutOfMem:
while (moves != NULL) {
move = moves->next;
cuddDeallocMove(table, moves);
moves = move;
}
return(MV_OOM);
} /* end of ddSymmSiftingUp */
/**Function********************************************************************
Synopsis [Swaps two groups.]
Description [Swaps two groups. x is assumed to be the bottom variable
of the first group. y is assumed to be the top variable of the second
group. Updates the list of moves. Returns the number of keys in the
table if successful; 0 otherwise.]
SideEffects [None]
SeeAlso []
******************************************************************************/
static int
zdd_group_move(
DdManager * table,
int x,
int y,
Move ** moves)
{
Move *move;
int size;
int i, temp, gxtop, gxbot, gybot, yprev;
int swapx, swapy;
/* NuSMV: add begin */
swapy = 0;
swapx = 0;
/* NuSMV: add end */
#ifdef DD_DEBUG
assert(x < y); /* we assume that x < y */
#endif
/* Find top and bottom for the two groups. */
gxtop = table->subtableZ[x].next;
gxbot = x;
gybot = table->subtableZ[y].next;
while (table->subtableZ[gybot].next != (unsigned) y)
gybot = table->subtableZ[gybot].next;
yprev = gybot;
while (x <= y) {
while (y > gxtop) {
/* Set correct symmetries. */
temp = table->subtableZ[x].next;
if (temp == x)
temp = y;
i = gxtop;
for (;;) {
if (table->subtableZ[i].next == (unsigned) x) {
table->subtableZ[i].next = y;
break;
} else {
i = table->subtableZ[i].next;
}
}
if (table->subtableZ[y].next != (unsigned) y) {
table->subtableZ[x].next = table->subtableZ[y].next;
} else {
table->subtableZ[x].next = x;
}
if (yprev != y) {
table->subtableZ[yprev].next = x;
} else {
yprev = x;
}
table->subtableZ[y].next = temp;
size = cuddZddSwapInPlace(table, x, y);
if (size == 0)
goto zdd_group_moveOutOfMem;
swapx = x;
swapy = y;
y = x;
x--;
} /* while y > gxtop */
/* Trying to find the next y. */
if (table->subtableZ[y].next <= (unsigned) y) {
gybot = y;
} else {
y = table->subtableZ[y].next;
}
yprev = gxtop;
gxtop++;
gxbot++;
x = gxbot;
} /* while x <= y, end of group movement */
move = (Move *)cuddDynamicAllocNode(table);
if (move == NULL)
goto zdd_group_moveOutOfMem;
move->x = swapx;
move->y = swapy;
move->size = table->keysZ;
move->next = *moves;
*moves = move;
return(table->keysZ);
zdd_group_moveOutOfMem:
while (*moves != NULL) {
move = (*moves)->next;
cuddDeallocMove(table, *moves);
*moves = move;
}
return(0);
} /* end of zdd_group_move */
/**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 */
/**Function********************************************************************
Synopsis [Given x_low <= x <= x_high moves x up and down between the
boundaries.]
Description [Given x_low <= x <= x_high 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]
SeeAlso []
******************************************************************************/
static int
cuddZddSymmSiftingConvAux(
DdManager * table,
int x,
int x_low,
int x_high)
{
Move *move;
Move *move_up; /* list of up move */
Move *move_down; /* list of down move */
int initial_size;
int result;
int i;
int init_group_size, final_group_size;
initial_size = table->keysZ;
move_down = NULL;
move_up = NULL;
if (x == x_low) { /* Sift down */
i = table->subtableZ[x].next;
init_group_size = x - i + 1;
move_down = cuddZddSymmSifting_down(table, x, x_high,
initial_size);
/* after that point x --> x_high, unless early term */
if (move_down == ZDD_MV_OOM)
goto cuddZddSymmSiftingConvAuxOutOfMem;
if (move_down == NULL ||
table->subtableZ[move_down->y].next != move_down->y) {
/* symmetry detected may have to make another complete
pass */
if (move_down != NULL)
x = move_down->y;
else {
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
x = table->subtableZ[x].next;
}
i = x;
while ((unsigned) i < table->subtableZ[i].next) {
i = table->subtableZ[i].next;
}
final_group_size = i - x + 1;
if (init_group_size == final_group_size) {
/* No new symmetries detected,
go back to best position */
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
}
else {
initial_size = table->keysZ;
move_up = cuddZddSymmSifting_up(table, x, x_low,
initial_size);
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
}
}
else {
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
/* move backward and stop at best position */
}
if (!result)
goto cuddZddSymmSiftingConvAuxOutOfMem;
}
else if (x == x_high) { /* Sift up */
/* Find top of x's symm group */
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
x = table->subtableZ[x].next;
i = x;
while ((unsigned) i < table->subtableZ[i].next) {
i = table->subtableZ[i].next;
}
init_group_size = i - x + 1;
move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size);
/* after that point x --> x_low, unless early term */
if (move_up == ZDD_MV_OOM)
goto cuddZddSymmSiftingConvAuxOutOfMem;
if (move_up == NULL ||
table->subtableZ[move_up->x].next != move_up->x) {
/* symmetry detected may have to make another complete
pass */
if (move_up != NULL)
x = move_up->x;
else {
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
}
i = table->subtableZ[x].next;
final_group_size = x - i + 1;
if (init_group_size == final_group_size) {
/* No new symmetry groups detected,
return to best position */
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
}
else {
initial_size = table->keysZ;
move_down = cuddZddSymmSifting_down(table, x, x_high,
initial_size);
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
}
}
else {
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
/* move backward and stop at best position */
}
if (!result)
goto cuddZddSymmSiftingConvAuxOutOfMem;
}
else if ((x - x_low) > (x_high - x)) { /* must go down first:
shorter */
move_down = cuddZddSymmSifting_down(table, x, x_high,
initial_size);
/* after that point x --> x_high */
if (move_down == ZDD_MV_OOM)
goto cuddZddSymmSiftingConvAuxOutOfMem;
if (move_down != NULL) {
x = move_down->y;
}
else {
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
x = table->subtableZ[x].next;
}
i = x;
while ((unsigned) i < table->subtableZ[i].next) {
i = table->subtableZ[i].next;
}
init_group_size = i - x + 1;
move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size);
if (move_up == ZDD_MV_OOM)
goto cuddZddSymmSiftingConvAuxOutOfMem;
if (move_up == NULL ||
table->subtableZ[move_up->x].next != move_up->x) {
/* symmetry detected may have to make another complete
pass */
if (move_up != NULL) {
x = move_up->x;
}
else {
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
}
i = table->subtableZ[x].next;
final_group_size = x - i + 1;
if (init_group_size == final_group_size) {
/* No new symmetry groups detected,
return to best position */
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
}
else {
while (move_down != NULL) {
move = move_down->next;
cuddDeallocMove(table, move_down);
move_down = move;
}
initial_size = table->keysZ;
move_down = cuddZddSymmSifting_down(table, x, x_high,
initial_size);
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
}
}
else {
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
/* move backward and stop at best position */
}
if (!result)
goto cuddZddSymmSiftingConvAuxOutOfMem;
}
else { /* moving up first:shorter */
/* Find top of x's symmetry group */
x = table->subtableZ[x].next;
move_up = cuddZddSymmSifting_up(table, x, x_low, initial_size);
/* after that point x --> x_high, unless early term */
if (move_up == ZDD_MV_OOM)
goto cuddZddSymmSiftingConvAuxOutOfMem;
if (move_up != NULL) {
x = move_up->x;
}
else {
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
}
i = table->subtableZ[x].next;
init_group_size = x - i + 1;
move_down = cuddZddSymmSifting_down(table, x, x_high,
initial_size);
if (move_down == ZDD_MV_OOM)
goto cuddZddSymmSiftingConvAuxOutOfMem;
if (move_down == NULL ||
table->subtableZ[move_down->y].next != move_down->y) {
/* symmetry detected may have to make another complete
pass */
if (move_down != NULL) {
x = move_down->y;
}
else {
while ((unsigned) x < table->subtableZ[x].next)
x = table->subtableZ[x].next;
x = table->subtableZ[x].next;
}
i = x;
while ((unsigned) i < table->subtableZ[i].next) {
i = table->subtableZ[i].next;
}
final_group_size = i - x + 1;
if (init_group_size == final_group_size) {
/* No new symmetries detected,
go back to best position */
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
}
else {
while (move_up != NULL) {
move = move_up->next;
cuddDeallocMove(table, move_up);
move_up = move;
}
initial_size = table->keysZ;
move_up = cuddZddSymmSifting_up(table, x, x_low,
initial_size);
result = cuddZddSymmSiftingBackward(table, move_up,
initial_size);
}
}
else {
result = cuddZddSymmSiftingBackward(table, move_down,
initial_size);
/* move backward and stop at best position */
}
if (!result)
goto cuddZddSymmSiftingConvAuxOutOfMem;
}
while (move_down != NULL) {
move = move_down->next;
cuddDeallocMove(table, move_down);
move_down = move;
}
while (move_up != NULL) {
move = move_up->next;
cuddDeallocMove(table, move_up);
move_up = move;
}
return(1);
cuddZddSymmSiftingConvAuxOutOfMem:
if (move_down != ZDD_MV_OOM) {
while (move_down != NULL) {
move = move_down->next;
cuddDeallocMove(table, move_down);
move_down = move;
}
}
if (move_up != ZDD_MV_OOM) {
while (move_up != NULL) {
move = move_up->next;
cuddDeallocMove(table, move_up);
move_up = move;
}
}
return(0);
} /* end of cuddZddSymmSiftingConvAux */
/**Function********************************************************************
Synopsis [Swaps two groups and records the move.]
Description [Swaps two groups and records the move. Returns the
number of keys in the DD table in case of success; 0 otherwise.]
SideEffects [None]
******************************************************************************/
static int
zddGroupMove(
DdManager * table,
int x,
int y,
Move ** moves)
{
Move *move;
int size;
int i,j,xtop,xbot,xsize,ytop,ybot,ysize,newxtop;
int swapx,swapy;
#if defined(DD_DEBUG) && defined(DD_VERBOSE)
int initialSize,bestSize;
#endif
#ifdef DD_DEBUG
/* We assume that x < y */
assert(x < y);
#endif
/* Find top, bottom, and size for the two groups. */
xbot = x;
xtop = table->subtableZ[x].next;
xsize = xbot - xtop + 1;
ybot = y;
while ((unsigned) ybot < table->subtableZ[ybot].next)
ybot = table->subtableZ[ybot].next;
ytop = y;
ysize = ybot - ytop + 1;
#if defined(DD_DEBUG) && defined(DD_VERBOSE)
initialSize = bestSize = table->keysZ;
#endif
/* Sift the variables of the second group up through the first group */
for (i = 1; i <= ysize; i++) {
for (j = 1; j <= xsize; j++) {
size = cuddZddSwapInPlace(table,x,y);
if (size == 0) goto zddGroupMoveOutOfMem;
#if defined(DD_DEBUG) && defined(DD_VERBOSE)
if (size < bestSize)
bestSize = size;
#endif
swapx = x; swapy = y;
y = x;
x = cuddZddNextLow(table,y);
}
y = ytop + i;
x = cuddZddNextLow(table,y);
}
#if defined(DD_DEBUG) && defined(DD_VERBOSE)
if ((bestSize < initialSize) && (bestSize < size))
(void) fprintf(table->out,"Missed local minimum: initialSize:%d bestSize:%d finalSize:%d\n",initialSize,bestSize,size);
#endif
/* fix groups */
y = xtop; /* ytop is now where xtop used to be */
for (i = 0; i < ysize - 1; i++) {
table->subtableZ[y].next = cuddZddNextHigh(table,y);
y = cuddZddNextHigh(table,y);
}
table->subtableZ[y].next = xtop; /* y is bottom of its group, join */
/* it to top of its group */
x = cuddZddNextHigh(table,y);
newxtop = x;
for (i = 0; i < xsize - 1; i++) {
table->subtableZ[x].next = cuddZddNextHigh(table,x);
x = cuddZddNextHigh(table,x);
}
table->subtableZ[x].next = newxtop; /* x is bottom of its group, join */
/* it to top of its group */
#ifdef DD_DEBUG
if (pr > 0) (void) fprintf(table->out,"zddGroupMove:\n");
#endif
/* Store group move */
move = (Move *) cuddDynamicAllocNode(table);
if (move == NULL) goto zddGroupMoveOutOfMem;
move->x = swapx;
move->y = swapy;
move->flags = MTR_DEFAULT;
move->size = table->keysZ;
move->next = *moves;
*moves = move;
return(table->keysZ);
zddGroupMoveOutOfMem:
while (*moves != NULL) {
move = (*moves)->next;
cuddDeallocMove(table, *moves);
*moves = move;
}
return(0);
} /* end of zddGroupMove */
