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/* 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)
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