/* SPDX-License-Identifier: GPL-2.0 */
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
#include <linux/linkage.h>
.macro GET_FRONT_BITS rx y
#ifdef __cskyLE__
lsri \rx, \y
#else
lsli \rx, \y
#endif
.endm
.macro GET_AFTER_BITS rx y
#ifdef __cskyLE__
lsli \rx, \y
#else
lsri \rx, \y
#endif
.endm
/* void *memcpy(void *dest, const void *src, size_t n); */
ENTRY(memcpy)
mov r7, r2
cmplti r4, 4
bt .L_copy_by_byte
mov r6, r2
andi r6, 3
cmpnei r6, 0
jbt .L_dest_not_aligned
mov r6, r3
andi r6, 3
cmpnei r6, 0
jbt .L_dest_aligned_but_src_not_aligned
.L0:
cmplti r4, 16
jbt .L_aligned_and_len_less_16bytes
subi sp, 8
stw r8, (sp, 0)
.L_aligned_and_len_larger_16bytes:
ldw r1, (r3, 0)
ldw r5, (r3, 4)
ldw r8, (r3, 8)
stw r1, (r7, 0)
ldw r1, (r3, 12)
stw r5, (r7, 4)
stw r8, (r7, 8)
stw r1, (r7, 12)
subi r4, 16
addi r3, 16
addi r7, 16
cmplti r4, 16
jbf .L_aligned_and_len_larger_16bytes
ldw r8, (sp, 0)
addi sp, 8
cmpnei r4, 0
jbf .L_return
.L_aligned_and_len_less_16bytes:
cmplti r4, 4
bt .L_copy_by_byte
.L1:
ldw r1, (r3, 0)
stw r1, (r7, 0)
subi r4, 4
addi r3, 4
addi r7, 4
cmplti r4, 4
jbf .L1
br .L_copy_by_byte
.L_return:
rts
.L_copy_by_byte: /* len less than 4 bytes */
cmpnei r4, 0
jbf .L_return
.L4:
ldb r1, (r3, 0)
stb r1, (r7, 0)
addi r3, 1
addi r7, 1
decne r4
jbt .L4
rts
/*
* If dest is not aligned, just copying some bytes makes the dest align.
* Afther that, we judge whether the src is aligned.
*/
.L_dest_not_aligned:
mov r5, r3
rsub r5, r5, r7
abs r5, r5
cmplt r5, r4
bt .L_copy_by_byte
mov r5, r7
sub r5, r3
cmphs r5, r4
bf .L_copy_by_byte
mov r5, r6
.L5:
ldb r1, (r3, 0) /* makes the dest align. */
stb r1, (r7, 0)
addi r5, 1
subi r4, 1
addi r3, 1
addi r7, 1
cmpnei r5, 4
jbt .L5
cmplti r4, 4
jbt .L_copy_by_byte
mov r6, r3 /* judge whether the src is aligned. */
andi r6, 3
cmpnei r6, 0
jbf .L0
/* Judge the number of misaligned, 1, 2, 3? */
.L_dest_aligned_but_src_not_aligned:
mov r5, r3
rsub r5, r5, r7
abs r5, r5
cmplt r5, r4
bt .L_copy_by_byte
bclri r3, 0
bclri r3, 1
ldw r1, (r3, 0)
addi r3, 4
cmpnei r6, 2
bf .L_dest_aligned_but_src_not_aligned_2bytes
cmpnei r6, 3
bf .L_dest_aligned_but_src_not_aligned_3bytes
.L_dest_aligned_but_src_not_aligned_1byte:
mov r5, r7
sub r5, r3
cmphs r5, r4
bf .L_copy_by_byte
cmplti r4, 16
bf .L11
.L10: /* If the len is less than 16 bytes */
GET_FRONT_BITS r1 8
mov r5, r1
ldw r6, (r3, 0)
mov r1, r6
GET_AFTER_BITS r6 24
or r5, r6
stw r5, (r7, 0)
subi r4, 4
addi r3, 4
addi r7, 4
cmplti r4, 4
bf .L10
subi r3, 3
br .L_copy_by_byte
.L11:
subi sp, 16
stw r8, (sp, 0)
stw r9, (sp, 4)
stw r10, (sp, 8)
stw r11, (sp, 12)
.L12:
ldw r5, (r3, 0)
ldw r11, (r3, 4)
ldw r8, (r3, 8)
ldw r9, (r3, 12)
GET_FRONT_BITS r1 8 /* little or big endian? */
mov r10, r5
GET_AFTER_BITS r5 24
or r5, r1
GET_FRONT_BITS r10 8
mov r1, r11
GET_AFTER_BITS r11 24
or r11, r10
GET_FRONT_BITS r1 8
mov r10, r8
GET_AFTER_BITS r8 24
or r8, r1
GET_FRONT_BITS r10 8
mov r1, r9
GET_AFTER_BITS r9 24
or r9, r10
stw r5, (r7, 0)
stw r11, (r7, 4)
stw r8, (r7, 8)
stw r9, (r7, 12)
subi r4, 16
addi r3, 16
addi r7, 16
cmplti r4, 16
jbf .L12
ldw r8, (sp, 0)
ldw r9, (sp, 4)
ldw r10, (sp, 8)
ldw r11, (sp, 12)
addi sp , 16
cmplti r4, 4
bf .L10
subi r3, 3
br .L_copy_by_byte
.L_dest_aligned_but_src_not_aligned_2bytes:
cmplti r4, 16
bf .L21
.L20:
GET_FRONT_BITS r1 16
mov r5, r1
ldw r6, (r3, 0)
mov r1, r6
GET_AFTER_BITS r6 16
or r5, r6
stw r5, (r7, 0)
subi r4, 4
addi r3, 4
addi r7, 4
cmplti r4, 4
bf .L20
subi r3, 2
br .L_copy_by_byte
rts
.L21: /* n > 16 */
subi sp, 16
stw r8, (sp, 0)
stw r9, (sp, 4)
stw r10, (sp, 8)
stw r11, (sp, 12)
.L22:
ldw r5, (r3, 0)
ldw r11, (r3, 4)
ldw r8, (r3, 8)
ldw r9, (r3, 12)
GET_FRONT_BITS r1 16
mov r10, r5
GET_AFTER_BITS r5 16
or r5, r1
GET_FRONT_BITS r10 16
mov r1, r11
GET_AFTER_BITS r11 16
or r11, r10
GET_FRONT_BITS r1 16
mov r10, r8
GET_AFTER_BITS r8 16
or r8, r1
GET_FRONT_BITS r10 16
mov r1, r9
GET_AFTER_BITS r9 16
or r9, r10
stw r5, (r7, 0)
stw r11, (r7, 4)
stw r8, (r7, 8)
stw r9, (r7, 12)
subi r4, 16
addi r3, 16
addi r7, 16
cmplti r4, 16
jbf .L22
ldw r8, (sp, 0)
ldw r9, (sp, 4)
ldw r10, (sp, 8)
ldw r11, (sp, 12)
addi sp, 16
cmplti r4, 4
bf .L20
subi r3, 2
br .L_copy_by_byte
.L_dest_aligned_but_src_not_aligned_3bytes:
cmplti r4, 16
bf .L31
.L30:
GET_FRONT_BITS r1 24
mov r5, r1
ldw r6, (r3, 0)
mov r1, r6
GET_AFTER_BITS r6 8
or r5, r6
stw r5, (r7, 0)
subi r4, 4
addi r3, 4
addi r7, 4
cmplti r4, 4
bf .L30
subi r3, 1
br .L_copy_by_byte
.L31:
subi sp, 16
stw r8, (sp, 0)
stw r9, (sp, 4)
stw r10, (sp, 8)
stw r11, (sp, 12)
.L32:
ldw r5, (r3, 0)
ldw r11, (r3, 4)
ldw r8, (r3, 8)
ldw r9, (r3, 12)
GET_FRONT_BITS r1 24
mov r10, r5
GET_AFTER_BITS r5 8
or r5, r1
GET_FRONT_BITS r10 24
mov r1, r11
GET_AFTER_BITS r11 8
or r11, r10
GET_FRONT_BITS r1 24
mov r10, r8
GET_AFTER_BITS r8 8
or r8, r1
GET_FRONT_BITS r10 24
mov r1, r9
GET_AFTER_BITS r9 8
or r9, r10
stw r5, (r7, 0)
stw r11, (r7, 4)
stw r8, (r7, 8)
stw r9, (r7, 12)
subi r4, 16
addi r3, 16
addi r7, 16
cmplti r4, 16
jbf .L32
ldw r8, (sp, 0)
ldw r9, (sp, 4)
ldw r10, (sp, 8)
ldw r11, (sp, 12)
addi sp, 16
cmplti r4, 4
bf .L30
subi r3, 1
br .L_copy_by_byte
