NetBSD/sys/lib/libkern/arch/i386/ffs.S

21 lines
376 B
ArmAsm

/*
* Written by J.T. Conklin <jtc@netbsd.org>.
* Public domain.
*/
#include <machine/asm.h>
#if defined(LIBC_SCCS)
RCSID("$NetBSD: ffs.S,v 1.7 1999/08/23 09:07:35 kleink Exp $")
#endif
ENTRY(ffs)
bsfl 4(%esp),%eax
jz L1 /* ZF is set if all bits are 0 */
incl %eax /* bits numbered from 1, not 0 */
ret
_ALIGN_TEXT
L1: xorl %eax,%eax /* clear result */
ret