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/* $OpenBSD: ffs.S,v 1.1 2004/01/28 01:44:45 mickey 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 <machine/asm.h>
ENTRY(ffs)
bsfl %edi,%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
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