29 lines
529 B
ArmAsm
29 lines
529 B
ArmAsm
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! memchr() Author: Kees J. Bot
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! 27 Jan 1994
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.sect .text; .sect .rom; .sect .data; .sect .bss
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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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.sect .text
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.define _memchr
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_memchr:
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push bp
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mov bp, sp
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push di
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mov di, 4(bp) ! di = string
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movb al, 6(bp) ! The character to look for
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mov cx, 8(bp) ! Length
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cmpb cl, #1 ! 'Z' bit must be clear if cx = 0
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cld
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repne scasb
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jne failure
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lea ax, -1(di) ! Found
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pop di
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pop bp
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ret
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failure:xor ax, ax
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pop di
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pop bp
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ret
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