about summary refs log tree commit diff
path: root/sysdeps/powerpc/powerpc32/power7/mempcpy.S
blob: 4d0fc3cde440f39415ed84dcd809e00859fa8def (plain) (blame)
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
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
/* Optimized mempcpy implementation for POWER7.
   Copyright (C) 2010-2019 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
   <http://www.gnu.org/licenses/>.  */

#include <sysdep.h>

/* void * [r3] __mempcpy (void *dst [r3], void *src [r4], size_t len [r5]);
	Returns 'dst' + 'len'.  */

	.machine  power7
EALIGN (__mempcpy, 5, 0)
	CALL_MCOUNT

	stwu	1,-32(1)
	cfi_adjust_cfa_offset(32)
	stw	30,20(1)
	cfi_offset(30,(20-32))
	stw	31,24(1)
	mr	30,3
	cmplwi	cr1,5,31
	neg	0,3
	cfi_offset(31,-8)
	ble	cr1,L(copy_LT_32)  /* If move < 32 bytes use short move
					code.  */

	andi.	11,3,7	      /* Check alignment of DST.  */
	clrlwi	10,4,29	      /* Check alignment of SRC.  */
	cmplw	cr6,10,11     /* SRC and DST alignments match?  */
	mr	12,4
	mr	31,5
	bne	cr6,L(copy_GE_32_unaligned)

	srwi	9,5,3	      /* Number of full quadwords remaining.  */

	beq	L(copy_GE_32_aligned_cont)

	clrlwi	0,0,29
	mtcrf	0x01,0
	subf	31,0,5

	/* Get the SRC aligned to 8 bytes.  */

1:	bf	31,2f
	lbz	6,0(12)
	addi	12,12,1
	stb	6,0(3)
	addi	3,3,1
2:	bf	30,4f
	lhz	6,0(12)
	addi	12,12,2
	sth	6,0(3)
	addi	3,3,2
4:	bf	29,0f
	lwz	6,0(12)
	addi	12,12,4
	stw	6,0(3)
	addi	3,3,4
0:
	clrlwi	10,12,29      /* Check alignment of SRC again.  */
	srwi	9,31,3	      /* Number of full doublewords remaining.  */

L(copy_GE_32_aligned_cont):

	clrlwi	11,31,29
	mtcrf	0x01,9

	srwi	8,31,5
	cmplwi	cr1,9,4
	cmplwi	cr6,11,0
	mr	11,12

	/* Copy 1~3 doublewords so the main loop starts
	at a multiple of 32 bytes.  */

	bf	30,1f
	lfd	6,0(12)
	lfd	7,8(12)
	addi	11,12,16
	mtctr	8
	stfd	6,0(3)
	stfd	7,8(3)
	addi	10,3,16
	bf	31,4f
	lfd	0,16(12)
	stfd	0,16(3)
	blt	cr1,3f
	addi	11,12,24
	addi	10,3,24
	b	4f

	.align	4
1:	/* Copy 1 doubleword and set the counter.  */
	mr	10,3
	mtctr	8
	bf	31,4f
	lfd	6,0(12)
	addi	11,12,8
	stfd	6,0(3)
	addi	10,3,8

	.align	4
4:	/* Main aligned copy loop. Copies 32-bytes at a time.  */
	lfd	6,0(11)
	lfd	7,8(11)
	lfd	8,16(11)
	lfd	0,24(11)
	addi	11,11,32

	stfd	6,0(10)
	stfd	7,8(10)
	stfd	8,16(10)
	stfd	0,24(10)
	addi	10,10,32
	bdnz	4b
3:

	/* Check for tail bytes.  */

	clrrwi	0,31,3
	mtcrf	0x01,31
	beq	cr6,0f

.L9:
	add	3,3,0
	add	12,12,0

	/*  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

	lwz	6,0(12)
	addi	12,12,4
	stw	6,0(3)
	addi	3,3,4
2:	/* Copy 2 bytes.  */
	bf	30,1f

	lhz	6,0(12)
	addi	12,12,2
	sth	6,0(3)
	addi	3,3,2
1:	/* Copy 1 byte.  */
	bf	31,0f

	lbz	6,0(12)
	stb	6,0(3)
0:	/* Return DST + LEN pointer.  */
	add	3,30,5
	lwz	30,20(1)
	lwz	31,24(1)
	addi	1,1,32
	blr

	/* Handle copies of 0~31 bytes.  */
	.align	4
L(copy_LT_32):
	cmplwi	cr6,5,8
	mr	12,4
	mtcrf	0x01,5
	ble	cr6,L(copy_LE_8)

	/* At least 9 bytes to go.  */
	neg	8,4
	clrrwi	11,4,2
	andi.	0,8,3
	cmplwi	cr1,5,16
	mr	10,5
	beq	L(copy_LT_32_aligned)

	/* Force 4-bytes alignment for SRC.  */
	mtocrf  0x01,0
	subf	10,0,5
2:	bf	30,1f

	lhz	6,0(12)
	addi	12,12,2
	sth	6,0(3)
	addi	3,3,2
1:	bf	31,L(end_4bytes_alignment)

	lbz	6,0(12)
	addi	12,12,1
	stb	6,0(3)
	addi	3,3,1

	.align	4
L(end_4bytes_alignment):
	cmplwi	cr1,10,16
	mtcrf	0x01,10

L(copy_LT_32_aligned):
	/* At least 6 bytes to go, and SRC is word-aligned.  */
	blt	cr1,8f

	/* Copy 16 bytes.  */
	lwz	6,0(12)
	lwz	7,4(12)
	stw	6,0(3)
	lwz	8,8(12)
	stw	7,4(3)
	lwz	6,12(12)
	addi	12,12,16
	stw	8,8(3)
	stw	6,12(3)
	addi	3,3,16
8:	/* Copy 8 bytes.  */
	bf	28,4f

	lwz	6,0(12)
	lwz	7,4(12)
	addi	12,12,8
	stw	6,0(3)
	stw	7,4(3)
	addi	3,3,8
4:	/* Copy 4 bytes.  */
	bf	29,2f

	lwz	6,0(12)
	addi	12,12,4
	stw	6,0(3)
	addi	3,3,4
2:	/* Copy 2-3 bytes.  */
	bf	30,1f

	lhz	6,0(12)
	sth	6,0(3)
	bf	31,0f
	lbz	7,2(12)
	stb	7,2(3)

	/* Return DST + LEN pointer.  */
	add	3,30,5
	lwz	30,20(1)
	addi	1,1,32
	blr

	.align	4
1:	/* Copy 1 byte.  */
	bf	31,0f

	lbz	6,0(12)
	stb	6,0(3)
0:	/* Return DST + LEN pointer.  */
	add	3,30,5
	lwz	30,20(1)
	addi	1,1,32
	blr

	/* Handles copies of 0~8 bytes.  */
	.align	4
L(copy_LE_8):
	bne	cr6,4f

	/* Though we could've used lfd/stfd here, they are still
	slow for unaligned cases.  */

	lwz	6,0(4)
	lwz	7,4(4)
	stw	6,0(3)
	stw	7,4(3)

	/* Return DST + LEN pointer.  */
	add	3,30,5
	lwz	30,20(1)
	addi	1,1,32
	blr

	.align	4
4:	/* Copies 4~7 bytes.  */
	bf	29,2b

	lwz	6,0(4)
	stw	6,0(3)
	bf	30,5f
	lhz	7,4(4)
	sth	7,4(3)
	bf	31,0f
	lbz	8,6(4)
	stb	8,6(3)

	/* Return DST + LEN pointer.  */
	add	3,30,5
	lwz	30,20(1)
	addi	1,1,32
	blr

	.align	4
5:	/* Copy 1 byte.  */
	bf	31,0f

	lbz	6,4(4)
	stb	6,4(3)

0:	/* Return DST + LEN pointer.  */
	add	3,30,5
	lwz	30,20(1)
	addi	1,1,32
	blr

	/* Handle copies of 32+ bytes where DST is aligned (to quadword) but
	SRC is not. Use aligned quadword loads from SRC, shifted to realign
	the data, allowing for aligned DST stores.  */
	.align	4
L(copy_GE_32_unaligned):
	andi.	11,3,15	      /* Check alignment of DST.  */
	clrlwi	0,0,28	      /* Number of bytes until the 1st
				 quadword of DST.  */
	srwi	9,5,4	      /* Number of full quadwords remaining.  */

	beq	L(copy_GE_32_unaligned_cont)

	/* DST is not quadword aligned, get it aligned.  */

	mtcrf	0x01,0
	subf	31,0,5

	/* Vector instructions work best when proper alignment (16-bytes)
	is present.  Move 0~15 bytes as needed to get DST quadword-aligned.  */
1:	/* Copy 1 byte.  */
	bf	31,2f

	lbz	6,0(12)
	addi	12,12,1
	stb	6,0(3)
	addi	3,3,1
2:	/* Copy 2 bytes.  */
	bf		30,4f

	lhz	6,0(12)
	addi	12,12,2
	sth	6,0(3)
	addi	3,3,2
4:	/* Copy 4 bytes.  */
	bf	29,8f

	lwz	6,0(12)
	addi	12,12,4
	stw	6,0(3)
	addi	3,3,4
8:	/* Copy 8 bytes.  */
	bf	28,0f

	lfd	6,0(12)
	addi	12,12,8
	stfd	6,0(3)
	addi	3,3,8
0:
	clrlwi	10,12,28      /* Check alignment of SRC.  */
	srwi	9,31,4	      /* Number of full quadwords remaining.  */

	/* The proper alignment is present, it is OK to copy the bytes now.  */
L(copy_GE_32_unaligned_cont):

	/* Setup two indexes to speed up the indexed vector operations.  */
	clrlwi	11,31,28
	li	6,16	      /* Index for 16-bytes offsets.  */
	li	7,32	      /* Index for 32-bytes offsets.  */
	cmplwi	cr1,11,0
	srwi	8,31,5	      /* Setup the loop counter.  */
	mr	10,3
	mr	11,12
	mtcrf	0x01,9
	cmplwi	cr6,9,1
#ifdef __LITTLE_ENDIAN__
	lvsr    5,0,12
#else
	lvsl    5,0,12
#endif
	lvx	3,0,12
	bf	31,L(setup_unaligned_loop)

	/* Copy another 16 bytes to align to 32-bytes due to the loop .  */
	lvx	4,12,6
#ifdef __LITTLE_ENDIAN__
	vperm   6,4,3,5
#else
	vperm   6,3,4,5
#endif
	addi	11,12,16
	addi	10,3,16
	stvx	6,0,3
	vor	3,4,4

L(setup_unaligned_loop):
	mtctr	8
	ble	cr6,L(end_unaligned_loop)

	/* Copy 32 bytes at a time using vector instructions.  */
	.align	4
L(unaligned_loop):

	/* Note: vr6/vr10 may contain data that was already copied,
	but in order to get proper alignment, we may have to copy
	some portions again. This is faster than having unaligned
	vector instructions though.  */

	lvx	4,11,6	      /* vr4 = r11+16.  */
#ifdef __LITTLE_ENDIAN__
	vperm   6,4,3,5
#else
	vperm   6,3,4,5
#endif
	lvx	3,11,7	      /* vr3 = r11+32.  */
#ifdef __LITTLE_ENDIAN__
	vperm   10,3,4,5
#else
	vperm   10,4,3,5
#endif
	addi	11,11,32
	stvx	6,0,10
	stvx	10,10,6
	addi	10,10,32

	bdnz	L(unaligned_loop)

	.align	4
L(end_unaligned_loop):

	/* Check for tail bytes.  */
	clrrwi	0,31,4
	mtcrf	0x01,31
	beq	cr1,0f

	add	3,3,0
	add	12,12,0

	/*  We have 1~15 tail bytes to copy, and DST is quadword aligned.  */
8:	/* Copy 8 bytes.  */
	bf	28,4f

	lwz	6,0(12)
	lwz	7,4(12)
	addi	12,12,8
	stw	6,0(3)
	stw	7,4(3)
	addi	3,3,8
4:	/* Copy 4 bytes.  */
	bf	29,2f

	lwz	6,0(12)
	addi	12,12,4
	stw	6,0(3)
	addi	3,3,4
2:	/* Copy 2~3 bytes.  */
	bf	30,1f

	lhz	6,0(12)
	addi	12,12,2
	sth	6,0(3)
	addi	3,3,2
1:	/* Copy 1 byte.  */
	bf	31,0f

	lbz	6,0(12)
	stb	6,0(3)
0:	/* Return DST + LEN pointer.  */
	add	3,30,5
	lwz	30,20(1)
	lwz	31,24(1)
	addi	1,1,32
	blr

END (__mempcpy)
libc_hidden_def (__mempcpy)
weak_alias (__mempcpy, mempcpy)
libc_hidden_builtin_def (mempcpy)