blob: 3132b6316144f3e40b281bbe7a9748363ef64d4f [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0 */
/* memmove.S: Simple memmove implementation.
* Copyright (C) 1997, 2004 David S. Miller (
* Copyright (C) 1996, 1997, 1998, 1999 Jakub Jelinek (
#include <linux/linkage.h>
#include <asm/export.h>
ENTRY(memmove) /* o0=dst o1=src o2=len */
brz,pn %o2, 99f
mov %o0, %g1
cmp %o0, %o1
bleu,pt %xcc, 2f
add %o1, %o2, %g7
cmp %g7, %o0
bleu,pt %xcc, memcpy
add %o0, %o2, %o5
sub %g7, 1, %o1
sub %o5, 1, %o0
1: ldub [%o1], %g7
subcc %o2, 1, %o2
sub %o1, 1, %o1
stb %g7, [%o0]
bne,pt %icc, 1b
sub %o0, 1, %o0
mov %g1, %o0
/* We can't just call memcpy for these memmove cases. On some
* chips the memcpy uses cache initializing stores and when dst
* and src are close enough, those can clobber the source data
* before we've loaded it in.
2: or %o0, %o1, %g7
or %o2, %g7, %g7
andcc %g7, 0x7, %g0
bne,pn %xcc, 4f
3: ldx [%o1], %g7
add %o1, 8, %o1
subcc %o2, 8, %o2
add %o0, 8, %o0
bne,pt %icc, 3b
stx %g7, [%o0 - 0x8]
ba,a,pt %xcc, 99b
4: ldub [%o1], %g7
add %o1, 1, %o1
subcc %o2, 1, %o2
add %o0, 1, %o0
bne,pt %icc, 4b
stb %g7, [%o0 - 0x1]
ba,a,pt %xcc, 99b