Subversion Repositories or1k

/*
FUNCTION
	<<ffs>>---find first bit set in a word
 
INDEX
	ffs
 
ANSI_SYNOPSIS
	int ffs(int <[word]>);
 
TRAD_SYNOPSIS
	int ffs(<[word]>);
 
DESCRIPTION
 
<<ffs>> returns the first bit set in a word.
 
RETURNS
<<ffs>> returns 0 if <[c]> is 0, 1 if <[c]> is odd, 2 if <[c]> is a multiple of
2, etc.
 
PORTABILITY
<<ffs>> is not ANSI C.
 
No supporting OS subroutines are required.  */
 
int
ffs (word)
     int word;
{
  int i;
 
  if (!word)
    return 0;
 
  i = 0;
  for (;;)
    {
      if (((1 << i++) & word) != 0)
	return i;
    }
}