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Annotation of sys/lib/libkern/arch/amd64/ffs.S, Revision 1.1

1.1     ! nbrk        1: /*
        !             2:  * Written by J.T. Conklin <jtc@netbsd.org>.
        !             3:  * Public domain.
        !             4:  * Adapted for NetBSD/x86_64 by Frank van der Linden <fvdl@wasabisystems.com>
        !             5:  */
        !             6:
        !             7: #include <machine/asm.h>
        !             8:
        !             9: #if defined(LIBC_SCCS)
        !            10:        RCSID("$NetBSD: ffs.S,v 1.1 2001/06/19 00:22:46 fvdl Exp $")
        !            11: #endif
        !            12:
        !            13: ENTRY(ffs)
        !            14:        bsfl    %edi,%eax
        !            15:        jz      L1                      /* ZF is set if all bits are 0 */
        !            16:        incl    %eax                    /* bits numbered from 1, not 0 */
        !            17:        ret
        !            18:
        !            19:        _ALIGN_TEXT
        !            20: L1:    xorl    %eax,%eax               /* clear result */
        !            21:        ret