29 lines
568 B
ArmAsm
29 lines
568 B
ArmAsm
/* memchr() Author: Kees J. Bot */
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/* 2 Jan 1994 */
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/* void *memchr(const void *s, int c, size_t n) */
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/* Look for a character in a chunk of memory. */
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/* */
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#include <machine/asm.h>
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ENTRY(memchr)
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push %ebp
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movl %esp, %ebp
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push %edi
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movl 8(%ebp), %edi /* edi = string */
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movb 12(%ebp), %al /* The character to look for */
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movl 16(%ebp), %ecx /* Length */
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cmpb $1, %cl /* 'Z' bit must be clear if ecx = 0 */
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cld
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repne scasb
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jne failure
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leal -1(%edi), %eax /* Found */
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pop %edi
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pop %ebp
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ret
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failure:
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xorl %eax, %eax
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pop %edi
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pop %ebp
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ret
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