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