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Revision 1.1, Tue Mar 4 16:15:13 2008 UTC (16 years, 3 months ago) by nbrk
Branch point for: MAIN 

Initial revision

/*	$OpenBSD: ffs.S,v 1.2 1996/09/27 06:47:45 mickey Exp $	*/

/*
 * Written by J.T. Conklin <jtc@netbsd.org>.
 * Public domain.
 */

#include <machine/asm.h>

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 2
L1:	xorl	%eax,%eax		/* clear result */
	ret