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Revision 1.1, Tue Mar 4 16:15:12 2008 UTC (16 years, 6 months ago) by nbrk
Initial revision |
/* * 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 1.1 2001/06/19 00:22:46 fvdl Exp $") #endif 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