#include "misc/util/util_hack.h"
#include "cuddInt.h"

Functions
static DdNode *	zdd_subset1_aux (DdManager zdd, DdNode P, DdNode *zvar)

static DdNode *	zdd_subset0_aux (DdManager zdd, DdNode P, DdNode *zvar)

static void	zddVarToConst (DdNode f, DdNode gp, DdNode hp, DdNode base, DdNode *empty)

DdNode *	Cudd_zddIte (DdManager dd, DdNode f, DdNode g, DdNode h)

DdNode *	Cudd_zddUnion (DdManager dd, DdNode P, DdNode *Q)

DdNode *	Cudd_zddIntersect (DdManager dd, DdNode P, DdNode *Q)

DdNode *	Cudd_zddDiff (DdManager dd, DdNode P, DdNode *Q)

DdNode *	Cudd_zddDiffConst (DdManager zdd, DdNode P, DdNode *Q)

DdNode *	Cudd_zddSubset1 (DdManager dd, DdNode P, int var)

DdNode *	Cudd_zddSubset0 (DdManager dd, DdNode P, int var)

DdNode *	Cudd_zddChange (DdManager dd, DdNode P, int var)

DdNode *	cuddZddIte (DdManager dd, DdNode f, DdNode g, DdNode h)

DdNode *	cuddZddUnion (DdManager zdd, DdNode P, DdNode *Q)

DdNode *	cuddZddIntersect (DdManager zdd, DdNode P, DdNode *Q)

DdNode *	cuddZddDiff (DdManager zdd, DdNode P, DdNode *Q)

DdNode *	cuddZddChangeAux (DdManager zdd, DdNode P, DdNode *zvar)

DdNode *	cuddZddSubset1 (DdManager dd, DdNode P, int var)

DdNode *	cuddZddSubset0 (DdManager dd, DdNode P, int var)

DdNode *	cuddZddChange (DdManager dd, DdNode P, int var)

Variables
static ABC_NAMESPACE_IMPL_START char rcsid[]	DD_UNUSED = "$Id: cuddZddSetop.c,v 1.25 2004/08/13 18:04:54 fabio Exp $"

Function Documentation

DdNode* Cudd_zddChange	(	DdManager *	dd,
		DdNode *	P,
		int	var
	)

Function********************************************************************

Synopsis [Substitutes a variable with its complement in a ZDD.]

Description [Substitutes a variable with its complement in a ZDD. returns a pointer to the result if successful; NULL otherwise.]

SideEffects [None]

SeeAlso []

Definition at line 392 of file cuddZddSetop.c.

 {
     DdNode      *res;
 
     if ((unsigned int) var >= CUDD_MAXINDEX - 1) return(NULL);
     
     do {
         dd->reordered = 0;
         res = cuddZddChange(dd, P, var);
     } while (dd->reordered == 1);
     return(res);
 
 } /* end of Cudd_zddChange */

DdNode* Cudd_zddDiff	(	DdManager *	dd,
		DdNode *	P,
		DdNode *	Q
	)

Function********************************************************************

Synopsis [Computes the difference of two ZDDs.]

Description [Computes the difference of two ZDDs. Returns a pointer to the result if successful; NULL otherwise.]

SideEffects [None]

SeeAlso [Cudd_zddDiffConst]

Definition at line 236 of file cuddZddSetop.c.

 {
     DdNode *res;
 
     do {
         dd->reordered = 0;
         res = cuddZddDiff(dd, P, Q);
     } while (dd->reordered == 1);
     return(res);
 
 } /* end of Cudd_zddDiff */

DdNode* Cudd_zddDiffConst	(	DdManager *	zdd,
		DdNode *	P,
		DdNode *	Q
	)

Function********************************************************************

Synopsis [Performs the inclusion test for ZDDs (P implies Q).]

Description [Inclusion test for ZDDs (P implies Q). No new nodes are generated by this procedure. Returns empty if true; a valid pointer different from empty or DD_NON_CONSTANT otherwise.]

SideEffects [None]

SeeAlso [Cudd_zddDiff]

Definition at line 266 of file cuddZddSetop.c.

 {
     int         p_top, q_top;
     DdNode      *empty = DD_ZERO(zdd), *t, *res;
     DdManager   *table = zdd;
 
     statLine(zdd);
     if (P == empty)
         return(empty);
     if (Q == empty)
         return(P);
     if (P == Q)
         return(empty);
 
     /* Check cache.  The cache is shared by cuddZddDiff(). */
     res = cuddCacheLookup2Zdd(table, cuddZddDiff, P, Q);
     if (res != NULL)
         return(res);
 
     if (cuddIsConstant(P))
         p_top = P->index;
     else
         p_top = zdd->permZ[P->index];
     if (cuddIsConstant(Q))
         q_top = Q->index;
     else
         q_top = zdd->permZ[Q->index];
     if (p_top < q_top) {
         res = DD_NON_CONSTANT;
     } else if (p_top > q_top) {
         res = Cudd_zddDiffConst(zdd, P, cuddE(Q));
     } else {
         t = Cudd_zddDiffConst(zdd, cuddT(P), cuddT(Q));
         if (t != empty)
             res = DD_NON_CONSTANT;
         else
             res = Cudd_zddDiffConst(zdd, cuddE(P), cuddE(Q));
     }
 
     cuddCacheInsert2(table, cuddZddDiff, P, Q, res);
 
     return(res);
 
 } /* end of Cudd_zddDiffConst */

DdNode* Cudd_zddIntersect	(	DdManager *	dd,
		DdNode *	P,
		DdNode *	Q
	)

Function********************************************************************

Synopsis [Computes the intersection of two ZDDs.]

Description [Computes the intersection of two ZDDs. Returns a pointer to the result if successful; NULL otherwise.]

SideEffects [None]

SeeAlso []

Definition at line 207 of file cuddZddSetop.c.

 {
     DdNode *res;
 
     do {
         dd->reordered = 0;
         res = cuddZddIntersect(dd, P, Q);
     } while (dd->reordered == 1);
     return(res);
 
 } /* end of Cudd_zddIntersect */

DdNode* Cudd_zddIte	(	DdManager *	dd,
		DdNode *	f,
		DdNode *	g,
		DdNode *	h
	)

AutomaticEnd Function********************************************************************

Synopsis [Computes the ITE of three ZDDs.]

Description [Computes the ITE of three ZDDs. Returns a pointer to the result if successful; NULL otherwise.]

SideEffects [None]

SeeAlso []

Definition at line 148 of file cuddZddSetop.c.

 {
     DdNode *res;
 
     do {
         dd->reordered = 0;
         res = cuddZddIte(dd, f, g, h);
     } while (dd->reordered == 1);
     return(res);
 
 } /* end of Cudd_zddIte */

DdNode* Cudd_zddSubset0	(	DdManager *	dd,
		DdNode *	P,
		int	var
	)

Function********************************************************************

Synopsis [Computes the negative cofactor of a ZDD w.r.t. a variable.]

Description [Computes the negative cofactor of a ZDD w.r.t. a variable. In terms of combinations, the result is the set of all combinations in which the variable is negated. Returns a pointer to the result if successful; NULL otherwise.]

SideEffects [None]

SeeAlso [Cudd_zddSubset1]

Definition at line 362 of file cuddZddSetop.c.

 {
     DdNode      *r;
 
     do {
         dd->reordered = 0;
         r = cuddZddSubset0(dd, P, var);
     } while (dd->reordered == 1);
 
     return(r);
 
 } /* end of Cudd_zddSubset0 */

DdNode* Cudd_zddSubset1	(	DdManager *	dd,
		DdNode *	P,
		int	var
	)

Function********************************************************************

Synopsis [Computes the positive cofactor of a ZDD w.r.t. a variable.]

Description [Computes the positive cofactor of a ZDD w.r.t. a variable. In terms of combinations, the result is the set of all combinations in which the variable is asserted. Returns a pointer to the result if successful; NULL otherwise.]

SideEffects [None]

SeeAlso [Cudd_zddSubset0]

Definition at line 330 of file cuddZddSetop.c.

 {
     DdNode      *r;
 
     do {
         dd->reordered = 0;
         r = cuddZddSubset1(dd, P, var);
     } while (dd->reordered == 1);
 
     return(r);
 
 } /* end of Cudd_zddSubset1 */

DdNode* Cudd_zddUnion	(	DdManager *	dd,
		DdNode *	P,
		DdNode *	Q
	)

Function********************************************************************

Synopsis [Computes the union of two ZDDs.]

Description [Computes the union of two ZDDs. Returns a pointer to the result if successful; NULL otherwise.]

SideEffects [None]

SeeAlso []

Definition at line 178 of file cuddZddSetop.c.

 {
     DdNode *res;
 
     do {
         dd->reordered = 0;
         res = cuddZddUnion(dd, P, Q);
     } while (dd->reordered == 1);
     return(res);
 
 } /* end of Cudd_zddUnion */

DdNode* cuddZddChange	(	DdManager *	dd,
		DdNode *	P,
		int	var
	)

Function********************************************************************

Synopsis [Substitutes a variable with its complement in a ZDD.]

Description [Substitutes a variable with its complement in a ZDD. returns a pointer to the result if successful; NULL otherwise. cuddZddChange performs the same function as Cudd_zddChange, but does not restart if reordering has taken place. Therefore it can be called from within a recursive procedure.]

SideEffects [None]

SeeAlso [Cudd_zddChange]

Definition at line 971 of file cuddZddSetop.c.

 {
     DdNode      *zvar, *res;
 
     zvar = cuddUniqueInterZdd(dd, var, DD_ONE(dd), DD_ZERO(dd));
     if (zvar == NULL) return(NULL);
     cuddRef(zvar);
 
     res = cuddZddChangeAux(dd, P, zvar);
     if (res == NULL) {
         Cudd_RecursiveDerefZdd(dd,zvar);
         return(NULL);
     }
     cuddRef(res);
     Cudd_RecursiveDerefZdd(dd,zvar);
     cuddDeref(res);
     return(res);
 
 } /* end of cuddZddChange */

DdNode* cuddZddChangeAux	(	DdManager *	zdd,
		DdNode *	P,
		DdNode *	zvar
	)

Function********************************************************************

Synopsis [Performs the recursive step of Cudd_zddChange.]

Description []

SideEffects [None]

SeeAlso []

Definition at line 799 of file cuddZddSetop.c.

 {
     int         top_var, level;
     DdNode      *res, *t, *e;
     DdNode      *base = DD_ONE(zdd);
     DdNode      *empty = DD_ZERO(zdd);
 
     statLine(zdd);
     if (P == empty)
         return(empty);
     if (P == base)
         return(zvar);
 
     /* Check cache. */
     res = cuddCacheLookup2Zdd(zdd, cuddZddChangeAux, P, zvar);
     if (res != NULL)
         return(res);
 
     top_var = zdd->permZ[P->index];
     level = zdd->permZ[zvar->index];
 
     if (top_var > level) {
         res = cuddZddGetNode(zdd, zvar->index, P, DD_ZERO(zdd));
         if (res == NULL) return(NULL);
     } else if (top_var == level) {
         res = cuddZddGetNode(zdd, zvar->index, cuddE(P), cuddT(P));
         if (res == NULL) return(NULL);
     } else {
         t = cuddZddChangeAux(zdd, cuddT(P), zvar);
         if (t == NULL) return(NULL);
         cuddRef(t);
         e = cuddZddChangeAux(zdd, cuddE(P), zvar);
         if (e == NULL) {
             Cudd_RecursiveDerefZdd(zdd, t);
             return(NULL);
         }
         cuddRef(e);
         res = cuddZddGetNode(zdd, P->index, t, e);
         if (res == NULL) {
             Cudd_RecursiveDerefZdd(zdd, t);
             Cudd_RecursiveDerefZdd(zdd, e);
             return(NULL);
         }
         cuddDeref(t);
         cuddDeref(e);
     }
 
     cuddCacheInsert2(zdd, cuddZddChangeAux, P, zvar, res);
 
     return(res);
 
 } /* end of cuddZddChangeAux */

DdNode* cuddZddDiff	(	DdManager *	zdd,
		DdNode *	P,
		DdNode *	Q
	)

Function********************************************************************

Synopsis [Performs the recursive step of Cudd_zddDiff.]

Description []

SideEffects [None]

SeeAlso []

Definition at line 717 of file cuddZddSetop.c.

 {
     int         p_top, q_top;
     DdNode      *empty = DD_ZERO(zdd), *t, *e, *res;
     DdManager   *table = zdd;
 
     statLine(zdd);
     if (P == empty)
         return(empty);
     if (Q == empty)
         return(P);
     if (P == Q)
         return(empty);
 
     /* Check cache.  The cache is shared by Cudd_zddDiffConst(). */
     res = cuddCacheLookup2Zdd(table, cuddZddDiff, P, Q);
     if (res != NULL && res != DD_NON_CONSTANT)
         return(res);
 
     if (cuddIsConstant(P))
         p_top = P->index;
     else
         p_top = zdd->permZ[P->index];
     if (cuddIsConstant(Q))
         q_top = Q->index;
     else
         q_top = zdd->permZ[Q->index];
     if (p_top < q_top) {
         e = cuddZddDiff(zdd, cuddE(P), Q);
         if (e == NULL) return(NULL);
         cuddRef(e);
         res = cuddZddGetNode(zdd, P->index, cuddT(P), e);
         if (res == NULL) {
             Cudd_RecursiveDerefZdd(table, e);
             return(NULL);
         }
         cuddDeref(e);
     } else if (p_top > q_top) {
         res = cuddZddDiff(zdd, P, cuddE(Q));
         if (res == NULL) return(NULL);
     } else {
         t = cuddZddDiff(zdd, cuddT(P), cuddT(Q));
         if (t == NULL) return(NULL);
         cuddRef(t);
         e = cuddZddDiff(zdd, cuddE(P), cuddE(Q));
         if (e == NULL) {
             Cudd_RecursiveDerefZdd(table, t);
             return(NULL);
         }
         cuddRef(e);
         res = cuddZddGetNode(zdd, P->index, t, e);
         if (res == NULL) {
             Cudd_RecursiveDerefZdd(table, t);
             Cudd_RecursiveDerefZdd(table, e);
             return(NULL);
         }
         cuddDeref(t);
         cuddDeref(e);
     }
 
     cuddCacheInsert2(table, cuddZddDiff, P, Q, res);
 
     return(res);
 
 } /* end of cuddZddDiff */

DdNode* cuddZddIntersect	(	DdManager *	zdd,
		DdNode *	P,
		DdNode *	Q
	)

Function********************************************************************

Synopsis [Performs the recursive step of Cudd_zddIntersect.]

Description []

SideEffects [None]

SeeAlso []

Definition at line 642 of file cuddZddSetop.c.

 {
     int         p_top, q_top;
     DdNode      *empty = DD_ZERO(zdd), *t, *e, *res;
     DdManager   *table = zdd;
 
     statLine(zdd);
     if (P == empty)
         return(empty);
     if (Q == empty)
         return(empty);
     if (P == Q)
         return(P);
 
     /* Check cache. */
     res = cuddCacheLookup2Zdd(table, cuddZddIntersect, P, Q);
     if (res != NULL)
         return(res);
 
     if (cuddIsConstant(P))
         p_top = P->index;
     else
         p_top = zdd->permZ[P->index];
     if (cuddIsConstant(Q))
         q_top = Q->index;
     else
         q_top = zdd->permZ[Q->index];
     if (p_top < q_top) {
         res = cuddZddIntersect(zdd, cuddE(P), Q);
         if (res == NULL) return(NULL);
     } else if (p_top > q_top) {
         res = cuddZddIntersect(zdd, P, cuddE(Q));
         if (res == NULL) return(NULL);
     } else {
         t = cuddZddIntersect(zdd, cuddT(P), cuddT(Q));
         if (t == NULL) return(NULL);
         cuddRef(t);
         e = cuddZddIntersect(zdd, cuddE(P), cuddE(Q));
         if (e == NULL) {
             Cudd_RecursiveDerefZdd(table, t);
             return(NULL);
         }
         cuddRef(e);
         res = cuddZddGetNode(zdd, P->index, t, e);
         if (res == NULL) {
             Cudd_RecursiveDerefZdd(table, t);
             Cudd_RecursiveDerefZdd(table, e);
             return(NULL);
         }
         cuddDeref(t);
         cuddDeref(e);
     }
 
     cuddCacheInsert2(table, cuddZddIntersect, P, Q, res);
 
     return(res);
 
 } /* end of cuddZddIntersect */

DdNode* cuddZddIte	(	DdManager *	dd,
		DdNode *	f,
		DdNode *	g,
		DdNode *	h
	)

Function********************************************************************

Synopsis [Performs the recursive step of Cudd_zddIte.]

Description []

SideEffects [None]

SeeAlso []

Definition at line 427 of file cuddZddSetop.c.

 {
     DdNode *tautology, *empty;
     DdNode *r,*Gv,*Gvn,*Hv,*Hvn,*t,*e;
     unsigned int topf,topg,toph,v,top;
     int index;
 
     statLine(dd);
     /* Trivial cases. */
     /* One variable cases. */
     if (f == (empty = DD_ZERO(dd))) {   /* ITE(0,G,H) = H */
         return(h);
     }
     topf = cuddIZ(dd,f->index);
     topg = cuddIZ(dd,g->index);
     toph = cuddIZ(dd,h->index);
     v = ddMin(topg,toph);
     top  = ddMin(topf,v);
 
     tautology = (top == CUDD_MAXINDEX) ? DD_ONE(dd) : dd->univ[top];
     if (f == tautology) {                       /* ITE(1,G,H) = G */
         return(g);
     }
 
     /* From now on, f is known to not be a constant. */
     zddVarToConst(f,&g,&h,tautology,empty);
 
     /* Check remaining one variable cases. */
     if (g == h) {                       /* ITE(F,G,G) = G */
         return(g);
     }
 
     if (g == tautology) {                       /* ITE(F,1,0) = F */
         if (h == empty) return(f);
     }
 
     /* Check cache. */
     r = cuddCacheLookupZdd(dd,DD_ZDD_ITE_TAG,f,g,h);
     if (r != NULL) {
         return(r);
     }
 
     /* Recompute these because they may have changed in zddVarToConst. */
     topg = cuddIZ(dd,g->index);
     toph = cuddIZ(dd,h->index);
     v = ddMin(topg,toph);
 
     if (topf < v) {
         r = cuddZddIte(dd,cuddE(f),g,h);
         if (r == NULL) return(NULL);
     } else if (topf > v) {
         if (topg > v) {
             Gvn = g;
             index = h->index;
         } else {
             Gvn = cuddE(g);
             index = g->index;
         }
         if (toph > v) {
             Hv = empty; Hvn = h;
         } else {
             Hv = cuddT(h); Hvn = cuddE(h);
         }
         e = cuddZddIte(dd,f,Gvn,Hvn);
         if (e == NULL) return(NULL);
         cuddRef(e);
         r = cuddZddGetNode(dd,index,Hv,e);
         if (r == NULL) {
             Cudd_RecursiveDerefZdd(dd,e);
             return(NULL);
         }
         cuddDeref(e);
     } else {
         index = f->index;
         if (topg > v) {
             Gv = empty; Gvn = g;
         } else {
             Gv = cuddT(g); Gvn = cuddE(g);
         }
         if (toph > v) {
             Hv = empty; Hvn = h;
         } else {
             Hv = cuddT(h); Hvn = cuddE(h);
         }
         e = cuddZddIte(dd,cuddE(f),Gvn,Hvn);
         if (e == NULL) return(NULL);
         cuddRef(e);
         t = cuddZddIte(dd,cuddT(f),Gv,Hv);
         if (t == NULL) {
             Cudd_RecursiveDerefZdd(dd,e);
             return(NULL);
         }
         cuddRef(t);
         r = cuddZddGetNode(dd,index,t,e);
         if (r == NULL) {
             Cudd_RecursiveDerefZdd(dd,e);
             Cudd_RecursiveDerefZdd(dd,t);
             return(NULL);
         }
         cuddDeref(t);
         cuddDeref(e);
     }
 
     cuddCacheInsert(dd,DD_ZDD_ITE_TAG,f,g,h,r);
 
     return(r);
 
 } /* end of cuddZddIte */

DdNode* cuddZddSubset0	(	DdManager *	dd,
		DdNode *	P,
		int	var
	)

Function********************************************************************

Synopsis [Computes the negative cofactor of a ZDD w.r.t. a variable.]

Description [Computes the negative cofactor of a ZDD w.r.t. a variable. In terms of combinations, the result is the set of all combinations in which the variable is negated. Returns a pointer to the result if successful; NULL otherwise. cuddZddSubset0 performs the same function as Cudd_zddSubset0, but does not restart if reordering has taken place. Therefore it can be called from within a recursive procedure.]

SideEffects [None]

SeeAlso [cuddZddSubset1 Cudd_zddSubset0]

Definition at line 923 of file cuddZddSetop.c.

 {
     DdNode      *zvar, *r;
     DdNode      *base, *empty;
 
     base = DD_ONE(dd);
     empty = DD_ZERO(dd);
 
     zvar = cuddUniqueInterZdd(dd, var, base, empty);
     if (zvar == NULL) {
         return(NULL);
     } else {
         cuddRef(zvar);
         r = zdd_subset0_aux(dd, P, zvar);
         if (r == NULL) {
             Cudd_RecursiveDerefZdd(dd, zvar);
             return(NULL);
         }
         cuddRef(r);
         Cudd_RecursiveDerefZdd(dd, zvar);
     }
 
     cuddDeref(r);
     return(r);
 
 } /* end of cuddZddSubset0 */

DdNode* cuddZddSubset1	(	DdManager *	dd,
		DdNode *	P,
		int	var
	)

Function********************************************************************

Synopsis [Computes the positive cofactor of a ZDD w.r.t. a variable.]

Description [Computes the positive cofactor of a ZDD w.r.t. a variable. In terms of combinations, the result is the set of all combinations in which the variable is asserted. Returns a pointer to the result if successful; NULL otherwise. cuddZddSubset1 performs the same function as Cudd_zddSubset1, but does not restart if reordering has taken place. Therefore it can be called from within a recursive procedure.]

SideEffects [None]

SeeAlso [cuddZddSubset0 Cudd_zddSubset1]

Definition at line 874 of file cuddZddSetop.c.

 {
     DdNode      *zvar, *r;
     DdNode      *base, *empty;
 
     base = DD_ONE(dd);
     empty = DD_ZERO(dd);
 
     zvar = cuddUniqueInterZdd(dd, var, base, empty);
     if (zvar == NULL) {
         return(NULL);
     } else {
         cuddRef(zvar);
         r = zdd_subset1_aux(dd, P, zvar);
         if (r == NULL) {
             Cudd_RecursiveDerefZdd(dd, zvar);
             return(NULL);
         }
         cuddRef(r);
         Cudd_RecursiveDerefZdd(dd, zvar);
     }
 
     cuddDeref(r);
     return(r);
 
 } /* end of cuddZddSubset1 */

DdNode* cuddZddUnion	(	DdManager *	zdd,
		DdNode *	P,
		DdNode *	Q
	)

Function********************************************************************

Synopsis [Performs the recursive step of Cudd_zddUnion.]

Description []

SideEffects [None]

SeeAlso []

Definition at line 553 of file cuddZddSetop.c.

 {
     int         p_top, q_top;
     DdNode      *empty = DD_ZERO(zdd), *t, *e, *res;
     DdManager   *table = zdd;
 
     statLine(zdd);
     if (P == empty)
         return(Q);
     if (Q == empty)
         return(P);
     if (P == Q)
         return(P);
 
     /* Check cache */
     res = cuddCacheLookup2Zdd(table, cuddZddUnion, P, Q);
     if (res != NULL)
         return(res);
 
     if (cuddIsConstant(P))
         p_top = P->index;
     else
         p_top = zdd->permZ[P->index];
     if (cuddIsConstant(Q))
         q_top = Q->index;
     else
         q_top = zdd->permZ[Q->index];
     if (p_top < q_top) {
         e = cuddZddUnion(zdd, cuddE(P), Q);
         if (e == NULL) return (NULL);
         cuddRef(e);
         res = cuddZddGetNode(zdd, P->index, cuddT(P), e);
         if (res == NULL) {
             Cudd_RecursiveDerefZdd(table, e);
             return(NULL);
         }
         cuddDeref(e);
     } else if (p_top > q_top) {
         e = cuddZddUnion(zdd, P, cuddE(Q));
         if (e == NULL) return(NULL);
         cuddRef(e);
         res = cuddZddGetNode(zdd, Q->index, cuddT(Q), e);
         if (res == NULL) {
             Cudd_RecursiveDerefZdd(table, e);
             return(NULL);
         }
         cuddDeref(e);
     } else {
         t = cuddZddUnion(zdd, cuddT(P), cuddT(Q));
         if (t == NULL) return(NULL);
         cuddRef(t);
         e = cuddZddUnion(zdd, cuddE(P), cuddE(Q));
         if (e == NULL) {
             Cudd_RecursiveDerefZdd(table, t);
             return(NULL);
         }
         cuddRef(e);
         res = cuddZddGetNode(zdd, P->index, t, e);
         if (res == NULL) {
             Cudd_RecursiveDerefZdd(table, t);
             Cudd_RecursiveDerefZdd(table, e);
             return(NULL);
         }
         cuddDeref(t);
         cuddDeref(e);
     }
 
     cuddCacheInsert2(table, cuddZddUnion, P, Q, res);
 
     return(res);
 
 } /* end of cuddZddUnion */

static DdNode * zdd_subset0_aux	(	DdManager *	zdd,
		DdNode *	P,
		DdNode *	zvar
	)

static

Function********************************************************************

Synopsis [Performs the recursive step of Cudd_zddSubset0.]

Description []

SideEffects [None]

SeeAlso []

Definition at line 1081 of file cuddZddSetop.c.

 {
     int         top_var, level;
     DdNode      *res, *t, *e;
 
     statLine(zdd);
 
     /* Check cache. */
     res = cuddCacheLookup2Zdd(zdd, zdd_subset0_aux, P, zvar);
     if (res != NULL)
         return(res);
 
     if (cuddIsConstant(P)) {
         res = P;
         cuddCacheInsert2(zdd, zdd_subset0_aux, P, zvar, res);
         return(res);
     }
 
     top_var = zdd->permZ[P->index];
     level = zdd->permZ[zvar->index];
 
     if (top_var > level) {
         res = P;
     }
     else if (top_var == level) {
         res = cuddE(P);
     }
     else {
         t = zdd_subset0_aux(zdd, cuddT(P), zvar);
         if (t == NULL) return(NULL);
         cuddRef(t);
         e = zdd_subset0_aux(zdd, cuddE(P), zvar);
         if (e == NULL) {
             Cudd_RecursiveDerefZdd(zdd, t);
             return(NULL);
         }
         cuddRef(e);
         res = cuddZddGetNode(zdd, P->index, t, e);
         if (res == NULL) {
             Cudd_RecursiveDerefZdd(zdd, t);
             Cudd_RecursiveDerefZdd(zdd, e);
             return(NULL);
         }
         cuddDeref(t);
         cuddDeref(e);
     }
 
     cuddCacheInsert2(zdd, zdd_subset0_aux, P, zvar, res);
 
     return(res);
 
 } /* end of zdd_subset0_aux */

static DdNode * zdd_subset1_aux	(	DdManager *	zdd,
		DdNode *	P,
		DdNode *	zvar
	)

static

AutomaticStart

Function********************************************************************

Synopsis [Performs the recursive step of Cudd_zddSubset1.]

Description []

SideEffects [None]

SeeAlso []

Definition at line 1012 of file cuddZddSetop.c.

 {
     int         top_var, level;
     DdNode      *res, *t, *e;
     DdNode      *empty;
 
     statLine(zdd);
     empty = DD_ZERO(zdd);
 
     /* Check cache. */
     res = cuddCacheLookup2Zdd(zdd, zdd_subset1_aux, P, zvar);
     if (res != NULL)
         return(res);
 
     if (cuddIsConstant(P)) {
         res = empty;
         cuddCacheInsert2(zdd, zdd_subset1_aux, P, zvar, res);
         return(res);
     }
 
     top_var = zdd->permZ[P->index];
     level = zdd->permZ[zvar->index];
 
     if (top_var > level) {
         res = empty;
     } else if (top_var == level) {
         res = cuddT(P);
     } else {
         t = zdd_subset1_aux(zdd, cuddT(P), zvar);
         if (t == NULL) return(NULL);
         cuddRef(t);
         e = zdd_subset1_aux(zdd, cuddE(P), zvar);
         if (e == NULL) {
             Cudd_RecursiveDerefZdd(zdd, t);
             return(NULL);
         }
         cuddRef(e);
         res = cuddZddGetNode(zdd, P->index, t, e);
         if (res == NULL) {
             Cudd_RecursiveDerefZdd(zdd, t);
             Cudd_RecursiveDerefZdd(zdd, e);
             return(NULL);
         }
         cuddDeref(t);
         cuddDeref(e);
     }
 
     cuddCacheInsert2(zdd, zdd_subset1_aux, P, zvar, res);
 
     return(res);
 
 } /* end of zdd_subset1_aux */

static void zddVarToConst	(	DdNode *	f,
		DdNode **	gp,
		DdNode **	hp,
		DdNode *	base,
		DdNode *	empty
	)

static

Function********************************************************************

Synopsis [Replaces variables with constants if possible (part of canonical form).]

Description []

SideEffects [None]

SeeAlso []

Definition at line 1151 of file cuddZddSetop.c.

 {
     DdNode *g = *gp;
     DdNode *h = *hp;
 
     if (f == g) { /* ITE(F,F,H) = ITE(F,1,H) = F + H */
         *gp = base;
     }
 
     if (f == h) { /* ITE(F,G,F) = ITE(F,G,0) = F * G */
         *hp = empty;
     }
 
 } /* end of zddVarToConst */

Variable Documentation

ABC_NAMESPACE_IMPL_START char rcsid [] DD_UNUSED = "$Id: cuddZddSetop.c,v 1.25 2004/08/13 18:04:54 fabio Exp $"

static

CFile***********************************************************************

FileName [cuddZddSetop.c]

PackageName [cudd]

Synopsis [Set operations on ZDDs.]

Description [External procedures included in this module:

Internal procedures included in this module:

Static procedures included in this module:

]

SeeAlso []

Author [Hyong-Kyoon Shin, In-Ho Moon]

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

Neither the name of the University of Colorado nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.]

Definition at line 103 of file cuddZddSetop.c.

Functions

Variables

Function Documentation

Variable Documentation