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
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
|
/* Optimized memset implementation for PowerPC32/POWER7.
Copyright (C) 2010-2020 Free Software Foundation, Inc.
Contributed by Luis Machado <luisgpm@br.ibm.com>.
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>
/* void * [r3] memset (void *s [r3], int c [r4], size_t n [r5]));
Returns 's'. */
.machine power7
EALIGN (memset, 5, 0)
CALL_MCOUNT
.align 4
L(_memset):
cmplwi cr7,5,31
cmplwi cr6,5,8
mr 10,3 /* Save original argument for later. */
mr 7,1 /* Save original r1 for later. */
cfi_offset(31,-8)
/* Replicate byte to word. */
insrwi 4,4,8,16
insrwi 4,4,16,0
ble cr6,L(small) /* If length <= 8, use short copy code. */
neg 0,3
ble cr7,L(medium) /* If length < 32, use medium copy code. */
/* Save our word twice to create a doubleword that we will later
copy to a FPR. */
stwu 1,-32(1)
andi. 11,10,7 /* Check alignment of DST. */
mr 12,5
stw 4,24(1)
stw 4,28(1)
beq L(big_aligned)
clrlwi 0,0,29
mtocrf 0x01,0
subf 5,0,5
/* Get DST aligned to 8 bytes. */
1: bf 31,2f
stb 4,0(10)
addi 10,10,1
2: bf 30,4f
sth 4,0(10)
addi 10,10,2
4: bf 29,L(big_aligned)
stw 4,0(10)
addi 10,10,4
.align 4
L(big_aligned):
cmplwi cr5,5,255
li 0,32
cmplwi cr1,5,160
dcbtst 0,10
cmplwi cr6,4,0
srwi 9,5,3 /* Number of full doublewords remaining. */
crand 27,26,21
mtocrf 0x01,9
bt 27,L(huge)
/* From this point on, we'll copy 32+ bytes and the value
isn't 0 (so we can't use dcbz). */
srwi 8,5,5
clrlwi 11,5,29
cmplwi cr6,11,0
cmplwi cr1,9,4
mtctr 8
/* Copy 1~3 doublewords so the main loop starts
at a multiple of 32 bytes. */
bf 30,1f
stw 4,0(10)
stw 4,4(10)
stw 4,8(10)
stw 4,12(10)
addi 10,10,16
bf 31,L(big_loop)
stw 4,0(10)
stw 4,4(10)
addi 10,10,8
mr 12,10
blt cr1,L(tail_bytes)
b L(big_loop)
.align 4
1: /* Copy 1 doubleword. */
bf 31,L(big_loop)
stw 4,0(10)
stw 4,4(10)
addi 10,10,8
/* First use a 32-bytes loop with stw's to try and avoid the LHS due
to the lfd we will do next. Also, ping-pong through r10 and r12
to avoid AGEN delays. */
.align 4
L(big_loop):
addi 12,10,32
stw 4,0(10)
stw 4,4(10)
stw 4,8(10)
stw 4,12(10)
stw 4,16(10)
stw 4,20(10)
stw 4,24(10)
stw 4,28(10)
bdz L(tail_bytes)
addi 10,10,64
stw 4,0(12)
stw 4,4(12)
stw 4,8(12)
stw 4,12(12)
stw 4,16(12)
stw 4,20(12)
stw 4,24(12)
stw 4,28(12)
bdnz L(big_loop_fast_setup)
mr 12,10
b L(tail_bytes)
/* Now that we're probably past the LHS window, use the VSX to
speed up the loop. */
L(big_loop_fast_setup):
li 11,24
li 6,16
lxvdsx 4,1,11
.align 4
L(big_loop_fast):
addi 12,10,32
stxvd2x 4,0,10
stxvd2x 4,10,6
bdz L(tail_bytes)
addi 10,10,64
stxvd2x 4,0,12
stxvd2x 4,12,6
bdnz L(big_loop_fast)
mr 12,10
.align 4
L(tail_bytes):
/* Check for tail bytes. */
mr 1,7 /* Restore r1. */
beqlr cr6
clrlwi 0,5,29
mtocrf 0x01,0
/* At this point we have a tail of 0-7 bytes and we know that the
destination is doubleword-aligned. */
4: /* Copy 4 bytes. */
bf 29,2f
stw 4,0(12)
addi 12,12,4
2: /* Copy 2 bytes. */
bf 30,1f
sth 4,0(12)
addi 12,12,2
1: /* Copy 1 byte. */
bflr 31
stb 4,0(12)
blr
/* Special case when value is 0 and we have a long length to deal
with. Use dcbz to zero out 128-bytes at a time. Before using
dcbz though, we need to get the destination 128-bytes aligned. */
.align 4
L(huge):
lfd 4,24(1)
andi. 11,10,127
neg 0,10
beq L(huge_aligned)
clrlwi 0,0,25
subf 5,0,5
srwi 0,0,3
mtocrf 0x01,0
/* Get DST aligned to 128 bytes. */
8: bf 28,4f
stfd 4,0(10)
stfd 4,8(10)
stfd 4,16(10)
stfd 4,24(10)
stfd 4,32(10)
stfd 4,40(10)
stfd 4,48(10)
stfd 4,56(10)
addi 10,10,64
.align 4
4: bf 29,2f
stfd 4,0(10)
stfd 4,8(10)
stfd 4,16(10)
stfd 4,24(10)
addi 10,10,32
.align 4
2: bf 30,1f
stfd 4,0(10)
stfd 4,8(10)
addi 10,10,16
.align 4
1: bf 31,L(huge_aligned)
stfd 4,0(10)
addi 10,10,8
L(huge_aligned):
srwi 8,5,7
clrlwi 11,5,25
cmplwi cr6,11,0
mtctr 8
/* Copies 128-bytes at a time. */
.align 4
L(huge_loop):
dcbz 0,10
addi 10,10,128
bdnz L(huge_loop)
/* We have a tail of 0~127 bytes to handle. */
mr 1,7 /* Restore r1. */
beqlr cr6
subf 9,3,10
subf 5,9,12
srwi 8,5,3
cmplwi cr6,8,0
mtocrf 0x01,8
/* We have a tail o 1~127 bytes. Copy up to 15 doublewords for
speed. We'll handle the resulting tail bytes later. */
beq cr6,L(tail)
8: bf 28,4f
stfd 4,0(10)
stfd 4,8(10)
stfd 4,16(10)
stfd 4,24(10)
stfd 4,32(10)
stfd 4,40(10)
stfd 4,48(10)
stfd 4,56(10)
addi 10,10,64
.align 4
4: bf 29,2f
stfd 4,0(10)
stfd 4,8(10)
stfd 4,16(10)
stfd 4,24(10)
addi 10,10,32
.align 4
2: bf 30,1f
stfd 4,0(10)
stfd 4,8(10)
addi 10,10,16
.align 4
1: bf 31,L(tail)
stfd 4,0(10)
addi 10,10,8
/* Handle the rest of the tail bytes here. */
L(tail):
mtocrf 0x01,5
.align 4
4: bf 29,2f
stw 4,0(10)
addi 10,10,4
.align 4
2: bf 30,1f
sth 4,0(10)
addi 10,10,2
.align 4
1: bflr 31
stb 4,0(10)
blr
/* Expanded tree to copy tail bytes without increments. */
.align 4
L(copy_tail):
bf 29,L(FXX)
stw 4,0(10)
bf 30,L(TFX)
sth 4,4(10)
bflr 31
stb 4,6(10)
blr
.align 4
L(FXX): bf 30,L(FFX)
sth 4,0(10)
bflr 31
stb 4,2(10)
blr
.align 4
L(TFX): bflr 31
stb 4,4(10)
blr
.align 4
L(FFX): bflr 31
stb 4,0(10)
blr
/* Handle copies of 9~31 bytes. */
.align 4
L(medium):
/* At least 9 bytes to go. */
andi. 11,10,3
clrlwi 0,0,30
beq L(medium_aligned)
/* Force 4-bytes alignment for DST. */
mtocrf 0x01,0
subf 5,0,5
1: /* Copy 1 byte. */
bf 31,2f
stb 4,0(10)
addi 10,10,1
2: /* Copy 2 bytes. */
bf 30,L(medium_aligned)
sth 4,0(10)
addi 10,10,2
.align 4
L(medium_aligned):
/* At least 6 bytes to go, and DST is word-aligned. */
cmplwi cr1,5,16
mtocrf 0x01,5
blt cr1,8f
/* Copy 16 bytes. */
stw 4,0(10)
stw 4,4(10)
stw 4,8(10)
stw 4,12(10)
addi 10,10,16
8: /* Copy 8 bytes. */
bf 28,4f
stw 4,0(10)
stw 4,4(10)
addi 10,10,8
4: /* Copy 4 bytes. */
bf 29,2f
stw 4,0(10)
addi 10,10,4
2: /* Copy 2-3 bytes. */
bf 30,1f
sth 4,0(10)
addi 10,10,2
1: /* Copy 1 byte. */
bflr 31
stb 4,0(10)
blr
/* Handles copies of 0~8 bytes. */
.align 4
L(small):
mtocrf 0x01,5
bne cr6,L(copy_tail)
stw 4,0(10)
stw 4,4(10)
blr
END (memset)
libc_hidden_builtin_def (memset)
|
