1/* ffs -- Find the first bit set in the parameter
2
3@deftypefn Supplemental int ffs (int @var{valu})
4
5Find the first (least significant) bit set in @var{valu}.  Bits are
6numbered from right to left, starting with bit 1 (corresponding to the
7value 1).  If @var{valu} is zero, zero is returned.
8
9@end deftypefn
10
11*/
12
13int
14ffs (valu)
15  register int valu;
16{
17  register int bit;
18
19  if (valu == 0)
20    return 0;
21
22  for (bit = 1; !(valu & 1); bit++)
23  	valu >>= 1;
24
25  return bit;
26}
27
28