27 lines
599 B
ArmAsm
27 lines
599 B
ArmAsm
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/* $OpenBSD: memchr.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(memchr)
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pushl %edi
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movl 8(%esp),%edi /* string address */
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movl 12(%esp),%eax /* set character to search for */
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movl 16(%esp),%ecx /* set length of search */
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testl %ecx,%ecx /* test for len == 0 */
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jz L1
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cld /* set search forward */
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repne /* search! */
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scasb
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jne L1 /* scan failed, return null */
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leal -1(%edi),%eax /* adjust result of scan */
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popl %edi
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ret
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.align 2,0x90
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L1: xorl %eax,%eax
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popl %edi
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ret
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