src/bdd/cudd/cuddSign.c File Reference

#include "util_hack.h"
#include "cuddInt.h"

Include dependency graph for cuddSign.c:

Go to the source code of this file.

Functions
static double *ddCofMintermAux	ARGS ((DdManager *dd, DdNode *node, st_table *table))
double *	Cudd_CofMinterm (DdManager *dd, DdNode *node)
static double *	ddCofMintermAux (DdManager *dd, DdNode *node, st_table *table)
Variables
static char rcsid[]	DD_UNUSED = "$Id: cuddSign.c,v 1.1.1.1 2003/02/24 22:23:53 wjiang Exp $"
static int	size

---

Function Documentation

static double* ddCofMintermAux ARGS

(

(DdManager *dd, DdNode *node, st_table *table)

)

[static]

AutomaticStart

double* Cudd_CofMinterm	(	DdManager *	dd,
		DdNode *	node
	)

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

Synopsis [Computes the fraction of minterms in the on-set of all the positive cofactors of a BDD or ADD.]

Description [Computes the fraction of minterms in the on-set of all the positive cofactors of DD. Returns the pointer to an array of doubles if successful; NULL otherwise. The array hs as many positions as there are BDD variables in the manager plus one. The last position of the array contains the fraction of the minterms in the ON-set of the function represented by the BDD or ADD. The other positions of the array hold the variable signatures.]

SideEffects [None]

Definition at line 100 of file cuddSign.c.

{
    st_table    *table;
    double      *values;
    double      *result = NULL;
    int         i, firstLevel;

#ifdef DD_STATS
    long startTime;
    startTime = util_cpu_time();
    num_calls = 0;
    table_mem = sizeof(st_table);
#endif

    table = st_init_table(st_ptrcmp, st_ptrhash);
    if (table == NULL) {
        (void) fprintf(dd->err,
                       "out-of-memory, couldn't measure DD cofactors.\n");
        dd->errorCode = CUDD_MEMORY_OUT;
        return(NULL);
    }
    size = dd->size;
    values = ddCofMintermAux(dd, node, table);
    if (values != NULL) {
        result = ALLOC(double,size + 1);
        if (result != NULL) {
#ifdef DD_STATS
            table_mem += (size + 1) * sizeof(double);
#endif
            if (Cudd_IsConstant(node))
                firstLevel = 1;
            else
                firstLevel = cuddI(dd,Cudd_Regular(node)->index);
            for (i = 0; i < size; i++) {
                if (i >= cuddI(dd,Cudd_Regular(node)->index)) {
                    result[dd->invperm[i]] = values[i - firstLevel];
                } else {
                    result[dd->invperm[i]] = values[size - firstLevel];
                }
            }
            result[size] = values[size - firstLevel];
        } else {
            dd->errorCode = CUDD_MEMORY_OUT;
        }
    }

#ifdef DD_STATS
    table_mem += table->num_bins * sizeof(st_table_entry *);
#endif
    if (Cudd_Regular(node)->ref == 1) FREE(values);
    st_foreach(table, cuddStCountfree, NULL);
    st_free_table(table);
#ifdef DD_STATS
    (void) fprintf(dd->out,"Number of calls: %d\tTable memory: %d bytes\n",
                  num_calls, table_mem);
    (void) fprintf(dd->out,"Time to compute measures: %s\n",
                  util_print_time(util_cpu_time() - startTime));
#endif
    if (result == NULL) {
        (void) fprintf(dd->out,
                       "out-of-memory, couldn't measure DD cofactors.\n");
        dd->errorCode = CUDD_MEMORY_OUT;
    }
    return(result);

} /* end of Cudd_CofMinterm */

static double* ddCofMintermAux	(	DdManager *	dd,
		DdNode *	node,
		st_table *	table
	)			[static]

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

Synopsis [Recursive Step for Cudd_CofMinterm function.]

Description [Traverses the DD node and computes the fraction of minterms in the on-set of all positive cofactors simultaneously. It allocates an array with two more entries than there are variables below the one labeling the node. One extra entry (the first in the array) is for the variable labeling the node. The other entry (the last one in the array) holds the fraction of minterms of the function rooted at node. Each other entry holds the value for one cofactor. The array is put in a symbol table, to avoid repeated computation, and its address is returned by the procedure, for use by the caller. Returns a pointer to the array of cofactor measures.]

SideEffects [None]

SeeAlso []

Definition at line 201 of file cuddSign.c.

{
    DdNode      *N;             /* regular version of node */
    DdNode      *Nv, *Nnv;
    double      *values;
    double      *valuesT, *valuesE;
    int         i;
    int         localSize, localSizeT, localSizeE;
    double      vT, vE;

    statLine(dd);
#ifdef DD_STATS
    num_calls++;
#endif

    if (st_lookup(table, (char *) node, (char **) &values)) {
        return(values);
    }

    N = Cudd_Regular(node);
    if (cuddIsConstant(N)) {
        localSize = 1;
    } else {
        localSize = size - cuddI(dd,N->index) + 1;
    }
    values = ALLOC(double, localSize);
    if (values == NULL) {
        dd->errorCode = CUDD_MEMORY_OUT;
        return(NULL);
    }

    if (cuddIsConstant(N)) {
        if (node == DD_ZERO(dd) || node == Cudd_Not(DD_ONE(dd))) {
            values[0] = 0.0;
        } else {
            values[0] = 1.0;
        }
    } else {
        Nv = Cudd_NotCond(cuddT(N),N!=node);
        Nnv = Cudd_NotCond(cuddE(N),N!=node);

        valuesT = ddCofMintermAux(dd, Nv, table);
        if (valuesT == NULL) return(NULL);
        valuesE = ddCofMintermAux(dd, Nnv, table);
        if (valuesE == NULL) return(NULL);

        if (Cudd_IsConstant(Nv)) {
            localSizeT = 1;
        } else {
            localSizeT = size - cuddI(dd,Cudd_Regular(Nv)->index) + 1;
        }
        if (Cudd_IsConstant(Nnv)) {
            localSizeE = 1;
        } else {
            localSizeE = size - cuddI(dd,Cudd_Regular(Nnv)->index) + 1;
        }
        values[0] = valuesT[localSizeT - 1];
        for (i = 1; i < localSize; i++) {
            if (i >= cuddI(dd,Cudd_Regular(Nv)->index) - cuddI(dd,N->index)) {
                vT = valuesT[i - cuddI(dd,Cudd_Regular(Nv)->index) +
                            cuddI(dd,N->index)];
            } else {
                vT = valuesT[localSizeT - 1];
            }
            if (i >= cuddI(dd,Cudd_Regular(Nnv)->index) - cuddI(dd,N->index)) {
                vE = valuesE[i - cuddI(dd,Cudd_Regular(Nnv)->index) +
                            cuddI(dd,N->index)];
            } else {
                vE = valuesE[localSizeE - 1];
            }
            values[i] = (vT + vE) / 2.0;
        }
        if (Cudd_Regular(Nv)->ref == 1) FREE(valuesT);
        if (Cudd_Regular(Nnv)->ref == 1) FREE(valuesE);
    }

    if (N->ref > 1) {
        if (st_add_direct(table, (char *) node, (char *) values) == ST_OUT_OF_MEM) {
            FREE(values);
            return(NULL);
        }
#ifdef DD_STATS
        table_mem += localSize * sizeof(double) + sizeof(st_table_entry);
#endif
    }
    return(values);

} /* end of ddCofMintermAux */

---

Variable Documentation

char rcsid [] DD_UNUSED = "$Id: cuddSign.c,v 1.1.1.1 2003/02/24 22:23:53 wjiang Exp $" [static]

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

FileName [cuddSign.c]

PackageName [cudd]

Synopsis [Computation of signatures]

Description [External procedures included in this module:

• Cudd_CofMinterm();

Static procedures included in this module:

• ddCofMintermAux()

]

Author [Fabio Somenzi]

Copyright [This file was created at the University of Colorado at Boulder. The University of Colorado at Boulder makes no warranty about the suitability of this software for any purpose. It is presented on an AS IS basis.]

Definition at line 52 of file cuddSign.c.

int size [static]

Definition at line 55 of file cuddSign.c.