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
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
|
/* strchr/strchrnul optimized with AVX2.
Copyright (C) 2017-2019 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/>. */
#if IS_IN (libc)
# include <sysdep.h>
# ifndef STRCHR
# define STRCHR __strchr_avx2
# endif
# ifdef USE_AS_WCSCHR
# define VPBROADCAST vpbroadcastd
# define VPCMPEQ vpcmpeqd
# define CHAR_REG esi
# else
# define VPBROADCAST vpbroadcastb
# define VPCMPEQ vpcmpeqb
# define CHAR_REG sil
# endif
# ifndef VZEROUPPER
# define VZEROUPPER vzeroupper
# endif
# define VEC_SIZE 32
.section .text.avx,"ax",@progbits
ENTRY (STRCHR)
movl %edi, %ecx
/* Broadcast CHAR to YMM0. */
vmovd %esi, %xmm0
vpxor %xmm9, %xmm9, %xmm9
VPBROADCAST %xmm0, %ymm0
/* Check if we may cross page boundary with one vector load. */
andl $(2 * VEC_SIZE - 1), %ecx
cmpl $VEC_SIZE, %ecx
ja L(cros_page_boundary)
/* Check the first VEC_SIZE bytes. Search for both CHAR and the
null byte. */
vmovdqu (%rdi), %ymm8
VPCMPEQ %ymm8, %ymm0, %ymm1
VPCMPEQ %ymm8, %ymm9, %ymm2
vpor %ymm1, %ymm2, %ymm1
vpmovmskb %ymm1, %eax
testl %eax, %eax
jnz L(first_vec_x0)
/* Align data for aligned loads in the loop. */
addq $VEC_SIZE, %rdi
andl $(VEC_SIZE - 1), %ecx
andq $-VEC_SIZE, %rdi
jmp L(more_4x_vec)
.p2align 4
L(cros_page_boundary):
andl $(VEC_SIZE - 1), %ecx
andq $-VEC_SIZE, %rdi
vmovdqu (%rdi), %ymm8
VPCMPEQ %ymm8, %ymm0, %ymm1
VPCMPEQ %ymm8, %ymm9, %ymm2
vpor %ymm1, %ymm2, %ymm1
vpmovmskb %ymm1, %eax
/* Remove the leading bytes. */
sarl %cl, %eax
testl %eax, %eax
jz L(aligned_more)
/* Found CHAR or the null byte. */
tzcntl %eax, %eax
addq %rcx, %rax
# ifdef USE_AS_STRCHRNUL
addq %rdi, %rax
# else
xorl %edx, %edx
leaq (%rdi, %rax), %rax
cmp (%rax), %CHAR_REG
cmovne %rdx, %rax
# endif
VZEROUPPER
ret
.p2align 4
L(aligned_more):
addq $VEC_SIZE, %rdi
L(more_4x_vec):
/* Check the first 4 * VEC_SIZE. Only one VEC_SIZE at a time
since data is only aligned to VEC_SIZE. */
vmovdqa (%rdi), %ymm8
VPCMPEQ %ymm8, %ymm0, %ymm1
VPCMPEQ %ymm8, %ymm9, %ymm2
vpor %ymm1, %ymm2, %ymm1
vpmovmskb %ymm1, %eax
testl %eax, %eax
jnz L(first_vec_x0)
vmovdqa VEC_SIZE(%rdi), %ymm8
VPCMPEQ %ymm8, %ymm0, %ymm1
VPCMPEQ %ymm8, %ymm9, %ymm2
vpor %ymm1, %ymm2, %ymm1
vpmovmskb %ymm1, %eax
testl %eax, %eax
jnz L(first_vec_x1)
vmovdqa (VEC_SIZE * 2)(%rdi), %ymm8
VPCMPEQ %ymm8, %ymm0, %ymm1
VPCMPEQ %ymm8, %ymm9, %ymm2
vpor %ymm1, %ymm2, %ymm1
vpmovmskb %ymm1, %eax
testl %eax, %eax
jnz L(first_vec_x2)
vmovdqa (VEC_SIZE * 3)(%rdi), %ymm8
VPCMPEQ %ymm8, %ymm0, %ymm1
VPCMPEQ %ymm8, %ymm9, %ymm2
vpor %ymm1, %ymm2, %ymm1
vpmovmskb %ymm1, %eax
testl %eax, %eax
jnz L(first_vec_x3)
addq $(VEC_SIZE * 4), %rdi
/* Align data to 4 * VEC_SIZE. */
movq %rdi, %rcx
andl $(4 * VEC_SIZE - 1), %ecx
andq $-(4 * VEC_SIZE), %rdi
.p2align 4
L(loop_4x_vec):
/* Compare 4 * VEC at a time forward. */
vmovdqa (%rdi), %ymm5
vmovdqa VEC_SIZE(%rdi), %ymm6
vmovdqa (VEC_SIZE * 2)(%rdi), %ymm7
vmovdqa (VEC_SIZE * 3)(%rdi), %ymm8
VPCMPEQ %ymm5, %ymm0, %ymm1
VPCMPEQ %ymm6, %ymm0, %ymm2
VPCMPEQ %ymm7, %ymm0, %ymm3
VPCMPEQ %ymm8, %ymm0, %ymm4
VPCMPEQ %ymm5, %ymm9, %ymm5
VPCMPEQ %ymm6, %ymm9, %ymm6
VPCMPEQ %ymm7, %ymm9, %ymm7
VPCMPEQ %ymm8, %ymm9, %ymm8
vpor %ymm1, %ymm5, %ymm1
vpor %ymm2, %ymm6, %ymm2
vpor %ymm3, %ymm7, %ymm3
vpor %ymm4, %ymm8, %ymm4
vpor %ymm1, %ymm2, %ymm5
vpor %ymm3, %ymm4, %ymm6
vpor %ymm5, %ymm6, %ymm5
vpmovmskb %ymm5, %eax
testl %eax, %eax
jnz L(4x_vec_end)
addq $(VEC_SIZE * 4), %rdi
jmp L(loop_4x_vec)
.p2align 4
L(first_vec_x0):
/* Found CHAR or the null byte. */
tzcntl %eax, %eax
# ifdef USE_AS_STRCHRNUL
addq %rdi, %rax
# else
xorl %edx, %edx
leaq (%rdi, %rax), %rax
cmp (%rax), %CHAR_REG
cmovne %rdx, %rax
# endif
VZEROUPPER
ret
.p2align 4
L(first_vec_x1):
tzcntl %eax, %eax
# ifdef USE_AS_STRCHRNUL
addq $VEC_SIZE, %rax
addq %rdi, %rax
# else
xorl %edx, %edx
leaq VEC_SIZE(%rdi, %rax), %rax
cmp (%rax), %CHAR_REG
cmovne %rdx, %rax
# endif
VZEROUPPER
ret
.p2align 4
L(first_vec_x2):
tzcntl %eax, %eax
# ifdef USE_AS_STRCHRNUL
addq $(VEC_SIZE * 2), %rax
addq %rdi, %rax
# else
xorl %edx, %edx
leaq (VEC_SIZE * 2)(%rdi, %rax), %rax
cmp (%rax), %CHAR_REG
cmovne %rdx, %rax
# endif
VZEROUPPER
ret
.p2align 4
L(4x_vec_end):
vpmovmskb %ymm1, %eax
testl %eax, %eax
jnz L(first_vec_x0)
vpmovmskb %ymm2, %eax
testl %eax, %eax
jnz L(first_vec_x1)
vpmovmskb %ymm3, %eax
testl %eax, %eax
jnz L(first_vec_x2)
vpmovmskb %ymm4, %eax
testl %eax, %eax
L(first_vec_x3):
tzcntl %eax, %eax
# ifdef USE_AS_STRCHRNUL
addq $(VEC_SIZE * 3), %rax
addq %rdi, %rax
# else
xorl %edx, %edx
leaq (VEC_SIZE * 3)(%rdi, %rax), %rax
cmp (%rax), %CHAR_REG
cmovne %rdx, %rax
# endif
VZEROUPPER
ret
END (STRCHR)
#endif
|
