1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
|
/* SPDX-License-Identifier: GPL-2.0 */
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
#include <linux/linkage.h>
#include "sysdep.h"
ENTRY(strlen)
/* Check if the start addr is aligned. */
mov r3, r0
andi r1, r0, 3
movi r2, 4
movi r0, 0
bnez r1, .L_start_not_aligned
LABLE_ALIGN
.L_start_addr_aligned:
/* Check if all the bytes in the word are not zero. */
ldw r1, (r3)
tstnbz r1
bf .L_string_tail
ldw r1, (r3, 4)
addi r0, 4
tstnbz r1
bf .L_string_tail
ldw r1, (r3, 8)
addi r0, 4
tstnbz r1
bf .L_string_tail
ldw r1, (r3, 12)
addi r0, 4
tstnbz r1
bf .L_string_tail
ldw r1, (r3, 16)
addi r0, 4
tstnbz r1
bf .L_string_tail
ldw r1, (r3, 20)
addi r0, 4
tstnbz r1
bf .L_string_tail
ldw r1, (r3, 24)
addi r0, 4
tstnbz r1
bf .L_string_tail
ldw r1, (r3, 28)
addi r0, 4
tstnbz r1
bf .L_string_tail
addi r0, 4
addi r3, 32
br .L_start_addr_aligned
.L_string_tail:
# ifdef __CSKYBE__
xtrb0 r3, r1
bez r3, .L_return
addi r0, 1
xtrb1 r3, r1
bez r3, .L_return
addi r0, 1
xtrb2 r3, r1
bez r3, .L_return
addi r0, 1
# else
xtrb3 r3, r1
bez r3, .L_return
addi r0, 1
xtrb2 r3, r1
bez r3, .L_return
addi r0, 1
xtrb1 r3, r1
bez r3, .L_return
addi r0, 1
# endif /* !__CSKYBE__ */
.L_return:
rts
.L_start_not_aligned:
sub r2, r2, r1
.L_start_not_aligned_loop:
ldb r1, (r3)
PRE_BNEZAD (r2)
addi r3, 1
bez r1, .L_return
addi r0, 1
BNEZAD (r2, .L_start_not_aligned_loop)
br .L_start_addr_aligned
ENDPROC(strlen)
|
