Functions to find irredundant SOP covers as ZDDs from BDDs. More...

#include "util.h"
#include "cuddInt.h"

Include dependency graph for cuddZddIsop.c:

Functions
DdNode *	Cudd_zddIsop (DdManager dd, DdNode L, DdNode U, DdNode *zdd_I)
	Computes an ISOP in ZDD form from BDDs. More...

DdNode *	Cudd_bddIsop (DdManager dd, DdNode L, DdNode *U)
	Computes a BDD in the interval between L and U with a simple sum-of-product cover. More...

DdNode *	Cudd_MakeBddFromZddCover (DdManager dd, DdNode node)
	Converts a ZDD cover to a BDD. More...

DdNode *	cuddZddIsop (DdManager dd, DdNode L, DdNode U, DdNode *zdd_I)
	Performs the recursive step of Cudd_zddIsop. More...

DdNode *	cuddBddIsop (DdManager dd, DdNode L, DdNode *U)
	Performs the recursive step of Cudd_bddIsop. More...

DdNode *	cuddMakeBddFromZddCover (DdManager dd, DdNode node)
	Converts a ZDD cover to a BDD. More...

Detailed Description

Functions to find irredundant SOP covers as ZDDs from BDDs.

Author: In-Ho Moon

Copyright

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Function Documentation

◆ Cudd_bddIsop()

DdNode* Cudd_bddIsop	(	DdManager *	dd,
		DdNode *	L,
		DdNode *	U
	)

Computes a BDD in the interval between L and U with a simple sum-of-product cover.

This procedure is similar to Cudd_zddIsop, but it does not return the ZDD for the cover.

Returns: a pointer to the BDD if successful; NULL otherwise.

Side effects None

See also: Cudd_zddIsop

◆ Cudd_MakeBddFromZddCover()

DdNode* Cudd_MakeBddFromZddCover	(	DdManager *	dd,
		DdNode *	node
	)

Converts a ZDD cover to a BDD.

Converts a ZDD cover to a BDD for the function represented by the cover.

Returns: a BDD node if successful; otherwise it returns NULL.

See also: Cudd_zddIsop

◆ Cudd_zddIsop()

DdNode* Cudd_zddIsop	(	DdManager *	dd,
		DdNode *	L,
		DdNode *	U,
		DdNode **	zdd_I
	)

Computes an ISOP in ZDD form from BDDs.

Computes an irredundant sum of products (ISOP) in ZDD form from BDDs. The two BDDs L and U represent the lower bound and the upper bound, respectively, of the function. The ISOP uses two ZDD variables for each BDD variable: One for the positive literal, and one for the negative literal. These two variables should be adjacent in the ZDD order. The two ZDD variables corresponding to BDD variable i should have indices 2i and 2i+1. The result of this procedure depends on the variable order. If successful, Cudd_zddIsop returns the BDD for the function chosen from the interval. The ZDD representing the irredundant cover is returned as a side effect in zdd_I. In case of failure, NULL is returned.

Returns: the BDD for the chosen function if successful; NULL otherwise.

Side effects zdd_I holds the pointer to the ZDD for the ISOP on: successful return.

See also: Cudd_bddIsop Cudd_zddVarsFromBddVars

◆ cuddBddIsop()

DdNode* cuddBddIsop	(	DdManager *	dd,
		DdNode *	L,
		DdNode *	U
	)

Performs the recursive step of Cudd_bddIsop.

Side effects None

See also: Cudd_bddIsop

◆ cuddMakeBddFromZddCover()

DdNode* cuddMakeBddFromZddCover	(	DdManager *	dd,
		DdNode *	node
	)

Converts a ZDD cover to a BDD.

It is a recursive algorithm that works as follows. First it computes 3 cofactors of a ZDD cover: f1, f0 and fd. Second, it compute BDDs (b1, b0 and bd) of f1, f0 and fd. Third, it computes T=b1+bd and E=b0+bd. Fourth, it computes ITE(v,T,E) where v is the variable which has the index of the top node of the ZDD cover. In this case, since the index of v can be larger than either the one of T or the one of E, cuddUniqueInterIVO is called, where IVO stands for independent from variable ordering.

Returns: a BDD node if successful; otherwise it returns NULL.

See also: Cudd_MakeBddFromZddCover

◆ cuddZddIsop()

DdNode* cuddZddIsop	(	DdManager *	dd,
		DdNode *	L,
		DdNode *	U,
		DdNode **	zdd_I
	)

Performs the recursive step of Cudd_zddIsop.

Side effects None

See also: Cudd_zddIsop