blob: dcba4ce7f1a55cff3fc0ffb464b99fff58710793 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
|
/* $OpenBSD: ffs.S,v 1.6 2018/07/03 23:14:05 mortimer Exp $ */
/*
* Written by J.T. Conklin <jtc@netbsd.org>.
* Public domain.
* Adapted for NetBSD/x86_64 by Frank van der Linden <fvdl@wasabisystems.com>
*/
#include "DEFS.h"
ENTRY(ffs)
RETGUARD_SETUP(ffs, r11)
bsfl %edi,%eax
jz L1 /* ZF is set if all bits are 0 */
incl %eax /* bits numbered from 1, not 0 */
jmp L2
_ALIGN_TEXT
L1: xorl %eax,%eax /* clear result */
L2: RETGUARD_CHECK(ffs, r11)
ret
END(ffs)
.protected ffs
|
