summaryrefslogtreecommitdiff
path: root/sysdeps/x86_64/memrchr.S
blob: ba77bbc1938afadf91d88d01cab8d931735ca1d5 (plain)
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
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
/* fast SSE2 memrchr with 64 byte loop and pmaxub instruction using

   Copyright (C) 2011-2019 Free Software Foundation, Inc.
   Contributed by Intel Corporation.
   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>

	.text
ENTRY (__memrchr)
	movd	%esi, %xmm1

	sub	$16, %RDX_LP
	jbe	L(length_less16)

	punpcklbw	%xmm1, %xmm1
	punpcklbw	%xmm1, %xmm1

	add	%RDX_LP, %RDI_LP
	pshufd	$0, %xmm1, %xmm1

	movdqu	(%rdi), %xmm0
	pcmpeqb	%xmm1, %xmm0

/* Check if there is a match.  */
	pmovmskb	%xmm0, %eax
	test	%eax, %eax
	jnz	L(matches0)

	sub	$64, %rdi
	mov	%edi, %ecx
	and	$15, %ecx
	jz	L(loop_prolog)

	add	$16, %rdi
	add	$16, %rdx
	and	$-16, %rdi
	sub	%rcx, %rdx

	.p2align 4
L(loop_prolog):
	sub	$64, %rdx
	jbe	L(exit_loop)

	movdqa	48(%rdi), %xmm0
	pcmpeqb	%xmm1, %xmm0
	pmovmskb	%xmm0, %eax
	test	%eax, %eax
	jnz	L(matches48)

	movdqa	32(%rdi), %xmm2
	pcmpeqb	%xmm1, %xmm2
	pmovmskb	%xmm2, %eax
	test	%eax, %eax
	jnz	L(matches32)

	movdqa	16(%rdi), %xmm3
	pcmpeqb	%xmm1, %xmm3
	pmovmskb	%xmm3, %eax
	test	%eax, %eax
	jnz	L(matches16)

	movdqa	(%rdi), %xmm4
	pcmpeqb	%xmm1, %xmm4
	pmovmskb	%xmm4, %eax
	test	%eax, %eax
	jnz	L(matches0)

	sub	$64, %rdi
	sub	$64, %rdx
	jbe	L(exit_loop)

	movdqa	48(%rdi), %xmm0
	pcmpeqb	%xmm1, %xmm0
	pmovmskb	%xmm0, %eax
	test	%eax, %eax
	jnz	L(matches48)

	movdqa	32(%rdi), %xmm2
	pcmpeqb	%xmm1, %xmm2
	pmovmskb	%xmm2, %eax
	test	%eax, %eax
	jnz	L(matches32)

	movdqa	16(%rdi), %xmm3
	pcmpeqb	%xmm1, %xmm3
	pmovmskb	%xmm3, %eax
	test	%eax, %eax
	jnz	L(matches16)

	movdqa	(%rdi), %xmm3
	pcmpeqb	%xmm1, %xmm3
	pmovmskb	%xmm3, %eax
	test	%eax, %eax
	jnz	L(matches0)

	mov	%edi, %ecx
	and	$63, %ecx
	jz	L(align64_loop)

	add	$64, %rdi
	add	$64, %rdx
	and	$-64, %rdi
	sub	%rcx, %rdx

	.p2align 4
L(align64_loop):
	sub	$64, %rdi
	sub	$64, %rdx
	jbe	L(exit_loop)

	movdqa	(%rdi), %xmm0
	movdqa	16(%rdi), %xmm2
	movdqa	32(%rdi), %xmm3
	movdqa	48(%rdi), %xmm4

	pcmpeqb	%xmm1, %xmm0
	pcmpeqb	%xmm1, %xmm2
	pcmpeqb	%xmm1, %xmm3
	pcmpeqb	%xmm1, %xmm4

	pmaxub	%xmm3, %xmm0
	pmaxub	%xmm4, %xmm2
	pmaxub	%xmm0, %xmm2
	pmovmskb	%xmm2, %eax

	test	%eax, %eax
	jz	L(align64_loop)

	pmovmskb	%xmm4, %eax
	test	%eax, %eax
	jnz	L(matches48)

	pmovmskb	%xmm3, %eax
	test	%eax, %eax
	jnz	L(matches32)

	movdqa	16(%rdi), %xmm2

	pcmpeqb	%xmm1, %xmm2
	pcmpeqb	(%rdi), %xmm1

	pmovmskb	%xmm2, %eax
	test	%eax, %eax
	jnz	L(matches16)

	pmovmskb	%xmm1, %eax
	bsr	%eax, %eax

	add	%rdi, %rax
	ret

	.p2align 4
L(exit_loop):
	add	$64, %edx
	cmp	$32, %edx
	jbe	L(exit_loop_32)

	movdqa	48(%rdi), %xmm0
	pcmpeqb	%xmm1, %xmm0
	pmovmskb	%xmm0, %eax
	test	%eax, %eax
	jnz	L(matches48)

	movdqa	32(%rdi), %xmm2
	pcmpeqb	%xmm1, %xmm2
	pmovmskb	%xmm2, %eax
	test	%eax, %eax
	jnz	L(matches32)

	movdqa	16(%rdi), %xmm3
	pcmpeqb	%xmm1, %xmm3
	pmovmskb	%xmm3, %eax
	test	%eax, %eax
	jnz	L(matches16_1)
	cmp	$48, %edx
	jbe	L(return_null)

	pcmpeqb	(%rdi), %xmm1
	pmovmskb	%xmm1, %eax
	test	%eax, %eax
	jnz	L(matches0_1)
	xor	%eax, %eax
	ret

	.p2align 4
L(exit_loop_32):
	movdqa	48(%rdi), %xmm0
	pcmpeqb	%xmm1, %xmm0
	pmovmskb	%xmm0, %eax
	test	%eax, %eax
	jnz	L(matches48_1)
	cmp	$16, %edx
	jbe	L(return_null)

	pcmpeqb	32(%rdi), %xmm1
	pmovmskb	%xmm1, %eax
	test	%eax, %eax
	jnz	L(matches32_1)
	xor	%eax, %eax
	ret

	.p2align 4
L(matches0):
	bsr	%eax, %eax
	add	%rdi, %rax
	ret

	.p2align 4
L(matches16):
	bsr	%eax, %eax
	lea	16(%rax, %rdi), %rax
	ret

	.p2align 4
L(matches32):
	bsr	%eax, %eax
	lea	32(%rax, %rdi), %rax
	ret

	.p2align 4
L(matches48):
	bsr	%eax, %eax
	lea	48(%rax, %rdi), %rax
	ret

	.p2align 4
L(matches0_1):
	bsr	%eax, %eax
	sub	$64, %rdx
	add	%rax, %rdx
	jl	L(return_null)
	add	%rdi, %rax
	ret

	.p2align 4
L(matches16_1):
	bsr	%eax, %eax
	sub	$48, %rdx
	add	%rax, %rdx
	jl	L(return_null)
	lea	16(%rdi, %rax), %rax
	ret

	.p2align 4
L(matches32_1):
	bsr	%eax, %eax
	sub	$32, %rdx
	add	%rax, %rdx
	jl	L(return_null)
	lea	32(%rdi, %rax), %rax
	ret

	.p2align 4
L(matches48_1):
	bsr	%eax, %eax
	sub	$16, %rdx
	add	%rax, %rdx
	jl	L(return_null)
	lea	48(%rdi, %rax), %rax
	ret

	.p2align 4
L(return_null):
	xor	%eax, %eax
	ret

	.p2align 4
L(length_less16_offset0):
	test	%edx, %edx
	jz	L(return_null)

	mov	%dl, %cl
	pcmpeqb	(%rdi), %xmm1

	mov	$1, %edx
	sal	%cl, %edx
	sub	$1, %edx

	pmovmskb	%xmm1, %eax

	and	%edx, %eax
	test	%eax, %eax
	jz	L(return_null)

	bsr	%eax, %eax
	add	%rdi, %rax
	ret

	.p2align 4
L(length_less16):
	punpcklbw	%xmm1, %xmm1
	punpcklbw	%xmm1, %xmm1

	add	$16, %edx

	pshufd	$0, %xmm1, %xmm1

	mov	%edi, %ecx
	and	$15, %ecx
	jz	L(length_less16_offset0)

	mov	%cl, %dh
	mov	%ecx, %esi
	add	%dl, %dh
	and	$-16, %rdi

	sub	$16, %dh
	ja	L(length_less16_part2)

	pcmpeqb	(%rdi), %xmm1
	pmovmskb	%xmm1, %eax

	sar	%cl, %eax
	mov	%dl, %cl

	mov	$1, %edx
	sal	%cl, %edx
	sub	$1, %edx

	and	%edx, %eax
	test	%eax, %eax
	jz	L(return_null)

	bsr	%eax, %eax
	add	%rdi, %rax
	add	%rsi, %rax
	ret

	.p2align 4
L(length_less16_part2):
	movdqa	16(%rdi), %xmm2
	pcmpeqb	%xmm1, %xmm2
	pmovmskb	%xmm2, %eax

	mov	%dh, %cl
	mov	$1, %edx
	sal	%cl, %edx
	sub	$1, %edx

	and	%edx, %eax

	test	%eax, %eax
	jnz	L(length_less16_part2_return)

	pcmpeqb	(%rdi), %xmm1
	pmovmskb	%xmm1, %eax

	mov	%esi, %ecx
	sar	%cl, %eax
	test	%eax, %eax
	jz	L(return_null)

	bsr	%eax, %eax
	add	%rdi, %rax
	add	%rsi, %rax
	ret

	.p2align 4
L(length_less16_part2_return):
	bsr	%eax, %eax
	lea	16(%rax, %rdi), %rax
	ret

END (__memrchr)
weak_alias (__memrchr, memrchr)