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#include "setarch.h"
#include "defines.h"
.global _memcpy
_memcpy:
; MOVP @(2/4,r7),A0P ; dst
; MOVP @(4/8,r7),A1P ; src
; MOVP @(6/12,r7),A2P ; len
MOVP A0P,A3P ; keep copy of final dst
ADDP A2P,A0P ; point to end of dst
CMPP A0P,A3P ; see if anything to do
beq quit
ADDP A2P,A1P ; point to end of src
; lets see if we can do this in words
or A0L,A2L ; or in the dst address
or A3L,A2L ; or the length
or A1L,A2L ; or the src address
btst #0,A2L ; see if the lsb is zero
bne byteloop
wordloop:
#ifdef __NORMAL_MODE__
sub #2,A1P
#else
subs #2,A1P ; point to word
#endif
mov.w @A1P,A2 ; get word
mov.w A2,@-A0P ; save word
CMPP A0P,A3P ; at the front again ?
bne wordloop
rts
byteloop:
#ifdef __NORMAL_MODE__
sub #1,A1P
#else
subs #1,A1P ; point to byte
#endif
mov.b @A1P,A2L ; get byte
mov.b A2L,@-A0P ; save byte
CMPP A0P,A3P ; at the front again ?
bne byteloop
; return with A0 pointing to dst
quit: rts
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