File: ffs.c

package info (click to toggle)
sdcc 4.2.0%2Bdfsg-1
  • links: PTS, VCS
  • area: main
  • in suites: bookworm
  • size: 105,232 kB
  • sloc: ansic: 956,095; cpp: 110,511; makefile: 59,314; sh: 29,875; asm: 17,178; perl: 12,136; yacc: 7,480; lisp: 1,672; python: 907; lex: 805; awk: 498; sed: 89
file content (26 lines) | stat: -rw-r--r-- 465 bytes parent folder | download | duplicates (96) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
 
/* ffs -- Find the first bit set in the parameter

@deftypefn Supplemental int ffs (int @var{valu})

Find the first (least significant) bit set in @var{valu}.  Bits are
numbered from right to left, starting with bit 1 (corresponding to the
value 1).  If @var{valu} is zero, zero is returned.

@end deftypefn

*/

int
ffs (register int valu)
{
  register int bit;

  if (valu == 0)
    return 0;

  for (bit = 1; !(valu & 1); bit++)
  	valu >>= 1;

  return bit;
}