18 lines
417 B
ArmAsm
18 lines
417 B
ArmAsm
/* $OpenBSD: ffs.S,v 1.1 2004/01/28 01:44:45 mickey Exp $ */
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/*
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* Written by J.T. Conklin <jtc@netbsd.org>.
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* Public domain.
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* Adapted for NetBSD/x86_64 by Frank van der Linden <fvdl@wasabisystems.com>
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*/
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#include <machine/asm.h>
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ENTRY(ffs)
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bsfl %edi,%eax
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jz L1 /* ZF is set if all bits are 0 */
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incl %eax /* bits numbered from 1, not 0 */
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ret
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_ALIGN_TEXT
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L1: xorl %eax,%eax /* clear result */
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ret
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