65 lines
1.3 KiB
ArmAsm
65 lines
1.3 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0 */
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/asm.h>
|
|
|
|
ENTRY(__memmove)
|
|
WEAK(memmove)
|
|
move t0, a0
|
|
move t1, a1
|
|
|
|
beq a0, a1, exit_memcpy
|
|
beqz a2, exit_memcpy
|
|
srli t2, a2, 0x2
|
|
|
|
slt t3, a0, a1
|
|
beqz t3, do_reverse
|
|
|
|
andi a2, a2, 0x3
|
|
li t4, 1
|
|
beqz t2, byte_copy
|
|
|
|
word_copy:
|
|
lw t3, 0(a1)
|
|
addi t2, t2, -1
|
|
addi a1, a1, 4
|
|
sw t3, 0(a0)
|
|
addi a0, a0, 4
|
|
bnez t2, word_copy
|
|
beqz a2, exit_memcpy
|
|
j byte_copy
|
|
|
|
do_reverse:
|
|
add a0, a0, a2
|
|
add a1, a1, a2
|
|
andi a2, a2, 0x3
|
|
li t4, -1
|
|
beqz t2, reverse_byte_copy
|
|
|
|
reverse_word_copy:
|
|
addi a1, a1, -4
|
|
addi t2, t2, -1
|
|
lw t3, 0(a1)
|
|
addi a0, a0, -4
|
|
sw t3, 0(a0)
|
|
bnez t2, reverse_word_copy
|
|
beqz a2, exit_memcpy
|
|
|
|
reverse_byte_copy:
|
|
addi a0, a0, -1
|
|
addi a1, a1, -1
|
|
|
|
byte_copy:
|
|
lb t3, 0(a1)
|
|
addi a2, a2, -1
|
|
sb t3, 0(a0)
|
|
add a1, a1, t4
|
|
add a0, a0, t4
|
|
bnez a2, byte_copy
|
|
|
|
exit_memcpy:
|
|
move a0, t0
|
|
move a1, t1
|
|
ret
|
|
END(__memmove)
|