newlib-cygwin/newlib/libc/machine/h8300/reg_memcpy.S

31 lines
537 B
ArmAsm

#include "setarch.h"
#include "defines.h"
; dst A0
; src A1
; len A2
.global ___reg_memcpy
___reg_memcpy:
MOVP A0P,A3P ; keep copy of result
ADDP A2P,A0P ; point to end of dst
ADDP A2P,A1P ; point to end of src
CMPP A0P,A3P ; see if anything to do
beq quit
loop:
#ifdef __NORMAL_MODE__
sub #1,A1P ; point to byte
#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 loop
; return with A0 pointing to dst
quit: rts