/*
 * Revision Control Information
 *
 * $Source$
 * $Author$
 * $Revision$
 * $Date$
 *
 */
#include "sis.h"
#include "pld_int.h"
#include <math.h>

/* Return the ceiling of log2(n). Use the fact that the floor of the binary
log of n is the highest-order bit of the integer representation */
int
intlog2(n)
int n;
{
    int i, j, ans;
    
    if(n <= 0) {
	(void) fprintf(stderr, "Error: can't take the log of %d\n", n);
	fail("");
    }

    /* Through the loop, ans is = floor(log2(n)), i = 2^ans */
    for(ans = 0, i = 1, j = n; (j = j >> 1) != 0; ++ans, (i = i<<1));

    /* if n = i, n = 2^ans, i.e., floor(log2(n)) = ceil(log2(n)).  Otherwise
       bump up ans to make it the ceil */
    if(n > i) ++ans;
	return ans;
}
	

void xl_binary1(value, length, string)
    int value;
    int length;
    char *string;
{
  int Position = 0;
  int remainder;
  int i;
  char string1[BUFSIZE];

  for ( i= 0; i < BUFSIZE; i++) string1[i] = '0';
  while (value != 0) {
    remainder = value % 2;
    value = (value - remainder) /2;
    if (remainder == 0) string1[Position++] = '0';
    else string1[Position++] = '1';
  };
  if (Position > length) {
    (void) printf(" The length of string of value '%d' greater than %d\n",value,length);
    exit(1);
  }
  for (i = 0; i < length; i++)
     string[i] = string1[length - 1 - i];

  string[length] = '\0';

}
/*--------------------------------------------------------------
   Given some subset of fanins of node in array Y, return an 
   int array corresponding to the indices of the fanins.
---------------------------------------------------------------*/
int *
xln_array_to_indices(Y, node)
  array_t *Y;
  node_t *node;
{
  int *lambda_indices;
  int j, index;
  node_t *fanin;

  lambda_indices = ALLOC(int, array_n(Y));
  for (j = 0; j < array_n(Y); j++) {
      fanin = array_fetch(node_t *, Y, j);
      index = node_get_fanin_index(node, fanin);
      lambda_indices[j] = index;
  }
  return lambda_indices;
}