4a8992271c
This patch introduces AArch64-specific memory functions (memcpy, memmove, memchr, memset). These functions are not optimised for any CPU implementation but can be used as a starting point once hardware is available. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
54 lines
1.2 KiB
ArmAsm
54 lines
1.2 KiB
ArmAsm
/*
|
|
* Copyright (C) 2013 ARM Ltd.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/assembler.h>
|
|
|
|
/*
|
|
* Copy a buffer from src to dest (alignment handled by the hardware)
|
|
*
|
|
* Parameters:
|
|
* x0 - dest
|
|
* x1 - src
|
|
* x2 - n
|
|
* Returns:
|
|
* x0 - dest
|
|
*/
|
|
ENTRY(memcpy)
|
|
mov x4, x0
|
|
subs x2, x2, #8
|
|
b.mi 2f
|
|
1: ldr x3, [x1], #8
|
|
subs x2, x2, #8
|
|
str x3, [x4], #8
|
|
b.pl 1b
|
|
2: adds x2, x2, #4
|
|
b.mi 3f
|
|
ldr w3, [x1], #4
|
|
sub x2, x2, #4
|
|
str w3, [x4], #4
|
|
3: adds x2, x2, #2
|
|
b.mi 4f
|
|
ldrh w3, [x1], #2
|
|
sub x2, x2, #2
|
|
strh w3, [x4], #2
|
|
4: adds x2, x2, #1
|
|
b.mi 5f
|
|
ldrb w3, [x1]
|
|
strb w3, [x4]
|
|
5: ret
|
|
ENDPROC(memcpy)
|