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/*
Copyright (c) 2009 Nick Clifton <nickc@redhat.com>
*/
.file "memcpy.S"
.section .text
.global _memcpy
.type _memcpy,@function
_memcpy:
#ifdef __RX_DISALLOW_STRING_INSNS__
/* Do not use the string instructions - they might prefetch
bytes from outside of valid memory. This is particularly
dangerous in I/O space. */
;; FIXME: It would be more space efficient to just branch to _memmove...
cmp #0, r3 ; If the count is zero, do nothing
beq 1f
mov r1, r14 ; Save a copy of DEST
2: mov.b [r2+], r5
mov.b r5, [r14+]
sub #1, r3
bne 2b
1: rts
#else
mov r1, r4 ; Save a copy of DEST
smovf ; Copy R2 (source) to R1 (dest). Stop after R3 bytes.
mov r4, r1 ; Return DEST
rts
#endif
.size _memcpy, . - _memcpy
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