18 lines
338 B
ArmAsm
18 lines
338 B
ArmAsm
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/* $OpenBSD: ffs.S,v 1.3 2005/08/07 11:30:38 espie 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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*/
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#include <machine/asm.h>
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ENTRY(ffs)
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bsfl 4(%esp),%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 2
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L1: xorl %eax,%eax /* clear result */
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ret
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