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
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
|
/* Optimized strrchr implementation using basic LoongArch instructions.
Copyright (C) 2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <sys/regdef.h>
#include <sys/asm.h>
#if IS_IN (libc)
# define STRRCHR __strrchr_aligned
#else
# define STRRCHR strrchr
#endif
LEAF(STRRCHR, 6)
slli.d t0, a0, 3
bstrins.d a0, zero, 2, 0
lu12i.w a2, 0x01010
ld.d t2, a0, 0
andi a1, a1, 0xff
ori a2, a2, 0x101
li.d t3, -1
bstrins.d a2, a2, 63, 32
sll.d t5, t3, t0
slli.d a3, a2, 7
orn t4, t2, t5
mul.d a1, a1, a2
sub.d t0, t4, a2
andn t1, a3, t4
and t1, t0, t1
beqz t1, L(find_tail)
ctz.d t0, t1
orn t0, zero, t0
xor t2, t4, a1
srl.d t0, t3, t0
orn t2, t2, t0
orn t2, t2, t5
revb.d t2, t2
sub.d t1, t2, a2
andn t0, a3, t2
and t1, t0, t1
ctz.d t0, t1
srli.d t0, t0, 3
addi.d a0, a0, 7
sub.d a0, a0, t0
maskeqz a0, a0, t1
jr ra
L(find_tail):
addi.d a4, a0, 8
addi.d a0, a0, 8
L(loop_ascii):
ld.d t2, a0, 0
sub.d t1, t2, a2
and t0, t1, a3
bnez t0, L(more_check)
ld.d t2, a0, 8
sub.d t1, t2, a2
and t0, t1, a3
addi.d a0, a0, 16
beqz t0, L(loop_ascii)
addi.d a0, a0, -8
L(more_check):
andn t0, a3, t2
and t1, t1, t0
bnez t1, L(tail)
addi.d a0, a0, 8
L(loop_nonascii):
ld.d t2, a0, 0
sub.d t1, t2, a2
andn t0, a3, t2
and t1, t0, t1
bnez t1, L(tail)
ld.d t2, a0, 8
addi.d a0, a0, 16
sub.d t1, t2, a2
andn t0, a3, t2
and t1, t0, t1
beqz t1, L(loop_nonascii)
addi.d a0, a0, -8
L(tail):
ctz.d t0, t1
orn t0, zero, t0
xor t2, t2, a1
srl.d t0, t3, t0
orn t2, t2, t0
revb.d t2, t2
sub.d t1, t2, a2
andn t0, a3, t2
and t1, t0, t1
bnez t1, L(count_pos)
L(find_loop):
beq a0, a4, L(find_end)
ld.d t2, a0, -8
addi.d a0, a0, -8
xor t2, t2, a1
sub.d t1, t2, a2
andn t0, a3, t2
and t1, t0, t1
beqz t1, L(find_loop)
revb.d t2, t2
sub.d t1, t2, a2
andn t0, a3, t2
and t1, t0, t1
L(count_pos):
ctz.d t0, t1
addi.d a0, a0, 7
srli.d t0, t0, 3
sub.d a0, a0, t0
jr ra
nop
L(find_end):
xor t2, t4, a1
orn t2, t2, t5
revb.d t2, t2
sub.d t1, t2, a2
andn t0, a3, t2
and t1, t0, t1
ctz.d t0, t1
srli.d t0, t0, 3
addi.d a0, a4, -1
sub.d a0, a0, t0
maskeqz a0, a0, t1
jr ra
END(STRRCHR)
libc_hidden_builtin_def(STRRCHR)
|
