minix/common/lib/libc/arch/x86_64/string/ffs.S

/*
 * 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>

#if defined(LIBC_SCCS)
	RCSID("$NetBSD: ffs.S,v 1.4 2009/07/20 15:21:00 christos Exp $")
#endif

ENTRY(ffs)
	bsfl	%edi,%eax
	jz	1f	 		/* ZF is set if all bits are 0 */
	incl	%eax			/* bits numbered from 1, not 0 */
	ret

1:	xorl	%eax,%eax		/* clear result */
	ret
Import unmodified NetBSD libc in trunk This patch imports the unmodified current version of NetBSD libc. The NetBSD includes are in /nbsd_include, while the libc code itself is split between lib/nbsd_libc and common/lib/libc. 2011-02-14 20:36:03 +01:00			`/*`
			`* 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>`

			`#if defined(LIBC_SCCS)`
			`RCSID("$NetBSD: ffs.S,v 1.4 2009/07/20 15:21:00 christos Exp $")`
			`#endif`

			`ENTRY(ffs)`
			`bsfl %edi,%eax`
			`jz 1f /* ZF is set if all bits are 0 */`
			`incl %eax /* bits numbered from 1, not 0 */`
			`ret`

			`1: xorl %eax,%eax /* clear result */`
			`ret`