28 lines
742 B
ArmAsm
28 lines
742 B
ArmAsm
! bcmp() 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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! int bcmp(const void *s1, const void *s2, size_t n)
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! Compare two chunks of memory.
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! This is a BSD routine that escaped from the kernel. Don't use.
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! (Alas it is not without some use, it reports the number of bytes
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! after the bytes that are equal. So it can't be simply replaced.)
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!
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.sect .text
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.define _bcmp
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_bcmp:
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push bp
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mov bp, sp
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push 8(bp)
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push 6(bp)
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push 4(bp)
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call _memcmp ! Let memcmp do the work
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mov sp, bp
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test ax, ax
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jz equal
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sub dx, 4(bp) ! Memcmp was nice enough to leave "si" in dx
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dec dx ! Number of bytes that are equal
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mov ax, 8(bp)
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sub ax, dx ! Number of bytes that are unequal
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equal: pop bp
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ret
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