/**Function********************************************************************
Synopsis [Existentially Abstracts all the variables in cube from f.]
Description [Abstracts all the variables in cube from f by summing
over all possible values taken by the variables. Returns the
abstracted ADD.]
SideEffects [None]
SeeAlso [Cudd_addUnivAbstract Cudd_bddExistAbstract
Cudd_addOrAbstract]
******************************************************************************/
DdNode *
Cudd_addExistAbstract(
DdManager * manager,
DdNode * f,
DdNode * cube)
{
DdNode *res;
two = cuddUniqueConst(manager,(CUDD_VALUE_TYPE) 2);
if (two == NULL) return(NULL);
cuddRef(two);
if (addCheckPositiveCube(manager, cube) == 0) {
(void) fprintf(manager->err,"Error: Can only abstract cubes");
return(NULL);
}
do {
manager->reordered = 0;
res = cuddAddExistAbstractRecur(manager, f, cube);
} while (manager->reordered == 1);
if (res == NULL) {
Cudd_RecursiveDeref(manager,two);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(manager,two);
cuddDeref(res);
return(res);
} /* end of Cudd_addExistAbstract */
/**
@brief Existentially Abstracts all the variables in cube from f.
@details Abstracts all the variables in cube from f by summing
over all possible values taken by the variables.
@return the abstracted %ADD.
@sideeffect None
@see Cudd_addUnivAbstract Cudd_bddExistAbstract
Cudd_addOrAbstract
*/
DdNode *
Cudd_addExistAbstract(
DdManager * manager,
DdNode * f,
DdNode * cube)
{
DdNode *res;
if (addCheckPositiveCube(manager, cube) == 0) {
(void) fprintf(manager->err,"Error: Can only abstract cubes");
return(NULL);
}
do {
manager->reordered = 0;
res = cuddAddExistAbstractRecur(manager, f, cube);
} while (manager->reordered == 1);
if (manager->errorCode == CUDD_TIMEOUT_EXPIRED && manager->timeoutHandler) {
manager->timeoutHandler(manager, manager->tohArg);
}
return(res);
} /* end of Cudd_addExistAbstract */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_addExistAbstract.]
Description [Performs the recursive step of Cudd_addExistAbstract.
Returns the ADD obtained by abstracting the variables of cube from f,
if successful; NULL otherwise.]
SideEffects [None]
SeeAlso []
******************************************************************************/
DdNode *
cuddAddExistAbstractRecur(
DdManager * manager,
DdNode * f,
DdNode * cube)
{
DdNode *T, *E, *res, *res1, *res2, *zero;
statLine(manager);
zero = DD_ZERO(manager);
/* Cube is guaranteed to be a cube at this point. */
if (f == zero || cuddIsConstant(cube)) {
return(f);
}
/* Abstract a variable that does not appear in f => multiply by 2. */
if (cuddI(manager,f->index) > cuddI(manager,cube->index)) {
res1 = cuddAddExistAbstractRecur(manager, f, cuddT(cube));
if (res1 == NULL) return(NULL);
cuddRef(res1);
/* Use the "internal" procedure to be alerted in case of
** dynamic reordering. If dynamic reordering occurs, we
** have to abort the entire abstraction.
*/
res = cuddAddApplyRecur(manager,Cudd_addTimes,res1,two);
if (res == NULL) {
Cudd_RecursiveDeref(manager,res1);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(manager,res1);
cuddDeref(res);
return(res);
}
if ((res = cuddCacheLookup2(manager, Cudd_addExistAbstract, f, cube)) != NULL) {
return(res);
}
T = cuddT(f);
E = cuddE(f);
/* If the two indices are the same, so are their levels. */
if (f->index == cube->index) {
res1 = cuddAddExistAbstractRecur(manager, T, cuddT(cube));
if (res1 == NULL) return(NULL);
cuddRef(res1);
res2 = cuddAddExistAbstractRecur(manager, E, cuddT(cube));
if (res2 == NULL) {
Cudd_RecursiveDeref(manager,res1);
return(NULL);
}
cuddRef(res2);
res = cuddAddApplyRecur(manager, Cudd_addPlus, res1, res2);
if (res == NULL) {
Cudd_RecursiveDeref(manager,res1);
Cudd_RecursiveDeref(manager,res2);
return(NULL);
}
cuddRef(res);
Cudd_RecursiveDeref(manager,res1);
Cudd_RecursiveDeref(manager,res2);
cuddCacheInsert2(manager, Cudd_addExistAbstract, f, cube, res);
cuddDeref(res);
return(res);
} else { /* if (cuddI(manager,f->index) < cuddI(manager,cube->index)) */
res1 = cuddAddExistAbstractRecur(manager, T, cube);
if (res1 == NULL) return(NULL);
cuddRef(res1);
res2 = cuddAddExistAbstractRecur(manager, E, cube);
if (res2 == NULL) {
Cudd_RecursiveDeref(manager,res1);
return(NULL);
}
cuddRef(res2);
res = (res1 == res2) ? res1 :
cuddUniqueInter(manager, (int) f->index, res1, res2);
if (res == NULL) {
Cudd_RecursiveDeref(manager,res1);
Cudd_RecursiveDeref(manager,res2);
return(NULL);
}
cuddDeref(res1);
cuddDeref(res2);
cuddCacheInsert2(manager, Cudd_addExistAbstract, f, cube, res);
return(res);
}
} /* end of cuddAddExistAbstractRecur */
/**Function********************************************************************
Synopsis [Performs the recursive step of Cudd_addNonSimCompose.]
Description []
SideEffects [None]
SeeAlso []
******************************************************************************/
static DdNode *
cuddAddNonSimComposeRecur(
DdManager * dd,
DdNode * f,
DdNode ** vector,
DdNode * key,
DdNode * cube,
int lastsub)
{
DdNode *f1, *f0, *key1, *key0, *cube1, *var;
DdNode *T,*E;
DdNode *r;
unsigned int top, topf, topk, topc;
unsigned int index;
int i;
DdNode **vect1;
DdNode **vect0;
statLine(dd);
/* If we are past the deepest substitution, return f. */
if (cube == DD_ONE(dd) || cuddIsConstant(f)) {
return(f);
}
/* If problem already solved, look up answer and return. */
r = cuddCacheLookup(dd,DD_ADD_NON_SIM_COMPOSE_TAG,f,key,cube);
if (r != NULL) {
return(r);
}
/* Find top variable. we just need to look at f, key, and cube,
** because all the varibles in the gi are in key.
*/
topf = cuddI(dd,f->index);
topk = cuddI(dd,key->index);
top = ddMin(topf,topk);
topc = cuddI(dd,cube->index);
top = ddMin(top,topc);
index = dd->invperm[top];
/* Compute the cofactors. */
if (topf == top) {
f1 = cuddT(f);
f0 = cuddE(f);
} else {
f1 = f0 = f;
}
if (topc == top) {
cube1 = cuddT(cube);
/* We want to eliminate vector[index] from key. Otherwise
** cache performance is severely affected. Hence we
** existentially quantify the variable with index "index" from key.
*/
var = Cudd_addIthVar(dd, (int) index);
if (var == NULL) {
return(NULL);
}
cuddRef(var);
key1 = cuddAddExistAbstractRecur(dd, key, var);
if (key1 == NULL) {
Cudd_RecursiveDeref(dd,var);
return(NULL);
}
cuddRef(key1);
Cudd_RecursiveDeref(dd,var);
key0 = key1;
} else {
cube1 = cube;
if (topk == top) {
key1 = cuddT(key);
key0 = cuddE(key);
} else {
key1 = key0 = key;
}
cuddRef(key1);
}
/* Allocate two new vectors for the cofactors of vector. */
vect1 = ALLOC(DdNode *,lastsub);
if (vect1 == NULL) {
dd->errorCode = CUDD_MEMORY_OUT;
Cudd_RecursiveDeref(dd,key1);
return(NULL);
}
vect0 = ALLOC(DdNode *,lastsub);
if (vect0 == NULL) {
dd->errorCode = CUDD_MEMORY_OUT;
Cudd_RecursiveDeref(dd,key1);
FREE(vect1);
return(NULL);
}
/* Cofactor the gi. Eliminate vect1[index] and vect0[index], because
** we do not need them.
*/
for (i = 0; i < lastsub; i++) {
DdNode *gi = vector[i];
if (gi == NULL) {
vect1[i] = vect0[i] = NULL;
} else if (gi->index == index) {
vect1[i] = cuddT(gi);
vect0[i] = cuddE(gi);
} else {
vect1[i] = vect0[i] = gi;
}
}
vect1[index] = vect0[index] = NULL;
/* Recur on children. */
T = cuddAddNonSimComposeRecur(dd,f1,vect1,key1,cube1,lastsub);
FREE(vect1);
if (T == NULL) {
Cudd_RecursiveDeref(dd,key1);
FREE(vect0);
return(NULL);
}
cuddRef(T);
E = cuddAddNonSimComposeRecur(dd,f0,vect0,key0,cube1,lastsub);
FREE(vect0);
if (E == NULL) {
Cudd_RecursiveDeref(dd,key1);
Cudd_RecursiveDeref(dd,T);
return(NULL);
}
cuddRef(E);
Cudd_RecursiveDeref(dd,key1);
/* Retrieve the 0-1 ADD for the current top variable from vector,
** and call cuddAddIteRecur with the T and E we just created.
*/
r = cuddAddIteRecur(dd,vector[index],T,E);
if (r == NULL) {
Cudd_RecursiveDeref(dd,T);
Cudd_RecursiveDeref(dd,E);
return(NULL);
}
cuddRef(r);
Cudd_RecursiveDeref(dd,T);
Cudd_RecursiveDeref(dd,E);
cuddDeref(r);
/* Store answer to trim recursion. */
cuddCacheInsert(dd,DD_ADD_NON_SIM_COMPOSE_TAG,f,key,cube,r);
return(r);
} /* end of cuddAddNonSimComposeRecur */
