summaryrefslogtreecommitdiffstats
path: root/media/libwebp/src/dsp/lossless_sse2.c
blob: 396cb0bdfcc3b8f0a180c7753389874af4c7df2b (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
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
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
// Copyright 2014 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
// SSE2 variant of methods for lossless decoder
//
// Author: Skal (pascal.massimino@gmail.com)

#include "src/dsp/dsp.h"

#if defined(WEBP_USE_SSE2)

#include "src/dsp/common_sse2.h"
#include "src/dsp/lossless.h"
#include "src/dsp/lossless_common.h"
#include <emmintrin.h>

//------------------------------------------------------------------------------
// Predictor Transform

static WEBP_INLINE uint32_t ClampedAddSubtractFull_SSE2(uint32_t c0,
                                                        uint32_t c1,
                                                        uint32_t c2) {
  const __m128i zero = _mm_setzero_si128();
  const __m128i C0 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(c0), zero);
  const __m128i C1 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(c1), zero);
  const __m128i C2 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(c2), zero);
  const __m128i V1 = _mm_add_epi16(C0, C1);
  const __m128i V2 = _mm_sub_epi16(V1, C2);
  const __m128i b = _mm_packus_epi16(V2, V2);
  const uint32_t output = _mm_cvtsi128_si32(b);
  return output;
}

static WEBP_INLINE uint32_t ClampedAddSubtractHalf_SSE2(uint32_t c0,
                                                        uint32_t c1,
                                                        uint32_t c2) {
  const __m128i zero = _mm_setzero_si128();
  const __m128i C0 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(c0), zero);
  const __m128i C1 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(c1), zero);
  const __m128i B0 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(c2), zero);
  const __m128i avg = _mm_add_epi16(C1, C0);
  const __m128i A0 = _mm_srli_epi16(avg, 1);
  const __m128i A1 = _mm_sub_epi16(A0, B0);
  const __m128i BgtA = _mm_cmpgt_epi16(B0, A0);
  const __m128i A2 = _mm_sub_epi16(A1, BgtA);
  const __m128i A3 = _mm_srai_epi16(A2, 1);
  const __m128i A4 = _mm_add_epi16(A0, A3);
  const __m128i A5 = _mm_packus_epi16(A4, A4);
  const uint32_t output = _mm_cvtsi128_si32(A5);
  return output;
}

static WEBP_INLINE uint32_t Select_SSE2(uint32_t a, uint32_t b, uint32_t c) {
  int pa_minus_pb;
  const __m128i zero = _mm_setzero_si128();
  const __m128i A0 = _mm_cvtsi32_si128(a);
  const __m128i B0 = _mm_cvtsi32_si128(b);
  const __m128i C0 = _mm_cvtsi32_si128(c);
  const __m128i AC0 = _mm_subs_epu8(A0, C0);
  const __m128i CA0 = _mm_subs_epu8(C0, A0);
  const __m128i BC0 = _mm_subs_epu8(B0, C0);
  const __m128i CB0 = _mm_subs_epu8(C0, B0);
  const __m128i AC = _mm_or_si128(AC0, CA0);
  const __m128i BC = _mm_or_si128(BC0, CB0);
  const __m128i pa = _mm_unpacklo_epi8(AC, zero);  // |a - c|
  const __m128i pb = _mm_unpacklo_epi8(BC, zero);  // |b - c|
  const __m128i diff = _mm_sub_epi16(pb, pa);
  {
    int16_t out[8];
    _mm_storeu_si128((__m128i*)out, diff);
    pa_minus_pb = out[0] + out[1] + out[2] + out[3];
  }
  return (pa_minus_pb <= 0) ? a : b;
}

static WEBP_INLINE void Average2_m128i(const __m128i* const a0,
                                       const __m128i* const a1,
                                       __m128i* const avg) {
  // (a + b) >> 1 = ((a + b + 1) >> 1) - ((a ^ b) & 1)
  const __m128i ones = _mm_set1_epi8(1);
  const __m128i avg1 = _mm_avg_epu8(*a0, *a1);
  const __m128i one = _mm_and_si128(_mm_xor_si128(*a0, *a1), ones);
  *avg = _mm_sub_epi8(avg1, one);
}

static WEBP_INLINE void Average2_uint32_SSE2(const uint32_t a0,
                                             const uint32_t a1,
                                             __m128i* const avg) {
  // (a + b) >> 1 = ((a + b + 1) >> 1) - ((a ^ b) & 1)
  const __m128i ones = _mm_set1_epi8(1);
  const __m128i A0 = _mm_cvtsi32_si128(a0);
  const __m128i A1 = _mm_cvtsi32_si128(a1);
  const __m128i avg1 = _mm_avg_epu8(A0, A1);
  const __m128i one = _mm_and_si128(_mm_xor_si128(A0, A1), ones);
  *avg = _mm_sub_epi8(avg1, one);
}

static WEBP_INLINE __m128i Average2_uint32_16_SSE2(uint32_t a0, uint32_t a1) {
  const __m128i zero = _mm_setzero_si128();
  const __m128i A0 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(a0), zero);
  const __m128i A1 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(a1), zero);
  const __m128i sum = _mm_add_epi16(A1, A0);
  return _mm_srli_epi16(sum, 1);
}

static WEBP_INLINE uint32_t Average2_SSE2(uint32_t a0, uint32_t a1) {
  __m128i output;
  Average2_uint32_SSE2(a0, a1, &output);
  return _mm_cvtsi128_si32(output);
}

static WEBP_INLINE uint32_t Average3_SSE2(uint32_t a0, uint32_t a1,
                                          uint32_t a2) {
  const __m128i zero = _mm_setzero_si128();
  const __m128i avg1 = Average2_uint32_16_SSE2(a0, a2);
  const __m128i A1 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(a1), zero);
  const __m128i sum = _mm_add_epi16(avg1, A1);
  const __m128i avg2 = _mm_srli_epi16(sum, 1);
  const __m128i A2 = _mm_packus_epi16(avg2, avg2);
  const uint32_t output = _mm_cvtsi128_si32(A2);
  return output;
}

static WEBP_INLINE uint32_t Average4_SSE2(uint32_t a0, uint32_t a1,
                                          uint32_t a2, uint32_t a3) {
  const __m128i avg1 = Average2_uint32_16_SSE2(a0, a1);
  const __m128i avg2 = Average2_uint32_16_SSE2(a2, a3);
  const __m128i sum = _mm_add_epi16(avg2, avg1);
  const __m128i avg3 = _mm_srli_epi16(sum, 1);
  const __m128i A0 = _mm_packus_epi16(avg3, avg3);
  const uint32_t output = _mm_cvtsi128_si32(A0);
  return output;
}

static uint32_t Predictor5_SSE2(const uint32_t* const left,
                                const uint32_t* const top) {
  const uint32_t pred = Average3_SSE2(*left, top[0], top[1]);
  return pred;
}
static uint32_t Predictor6_SSE2(const uint32_t* const left,
                                const uint32_t* const top) {
  const uint32_t pred = Average2_SSE2(*left, top[-1]);
  return pred;
}
static uint32_t Predictor7_SSE2(const uint32_t* const left,
                                const uint32_t* const top) {
  const uint32_t pred = Average2_SSE2(*left, top[0]);
  return pred;
}
static uint32_t Predictor8_SSE2(const uint32_t* const left,
                                const uint32_t* const top) {
  const uint32_t pred = Average2_SSE2(top[-1], top[0]);
  (void)left;
  return pred;
}
static uint32_t Predictor9_SSE2(const uint32_t* const left,
                                const uint32_t* const top) {
  const uint32_t pred = Average2_SSE2(top[0], top[1]);
  (void)left;
  return pred;
}
static uint32_t Predictor10_SSE2(const uint32_t* const left,
                                 const uint32_t* const top) {
  const uint32_t pred = Average4_SSE2(*left, top[-1], top[0], top[1]);
  return pred;
}
static uint32_t Predictor11_SSE2(const uint32_t* const left,
                                 const uint32_t* const top) {
  const uint32_t pred = Select_SSE2(top[0], *left, top[-1]);
  return pred;
}
static uint32_t Predictor12_SSE2(const uint32_t* const left,
                                 const uint32_t* const top) {
  const uint32_t pred = ClampedAddSubtractFull_SSE2(*left, top[0], top[-1]);
  return pred;
}
static uint32_t Predictor13_SSE2(const uint32_t* const left,
                                 const uint32_t* const top) {
  const uint32_t pred = ClampedAddSubtractHalf_SSE2(*left, top[0], top[-1]);
  return pred;
}

// Batch versions of those functions.

// Predictor0: ARGB_BLACK.
static void PredictorAdd0_SSE2(const uint32_t* in, const uint32_t* upper,
                               int num_pixels, uint32_t* out) {
  int i;
  const __m128i black = _mm_set1_epi32(ARGB_BLACK);
  for (i = 0; i + 4 <= num_pixels; i += 4) {
    const __m128i src = _mm_loadu_si128((const __m128i*)&in[i]);
    const __m128i res = _mm_add_epi8(src, black);
    _mm_storeu_si128((__m128i*)&out[i], res);
  }
  if (i != num_pixels) {
    VP8LPredictorsAdd_C[0](in + i, NULL, num_pixels - i, out + i);
  }
  (void)upper;
}

// Predictor1: left.
static void PredictorAdd1_SSE2(const uint32_t* in, const uint32_t* upper,
                               int num_pixels, uint32_t* out) {
  int i;
  __m128i prev = _mm_set1_epi32(out[-1]);
  for (i = 0; i + 4 <= num_pixels; i += 4) {
    // a | b | c | d
    const __m128i src = _mm_loadu_si128((const __m128i*)&in[i]);
    // 0 | a | b | c
    const __m128i shift0 = _mm_slli_si128(src, 4);
    // a | a + b | b + c | c + d
    const __m128i sum0 = _mm_add_epi8(src, shift0);
    // 0 | 0 | a | a + b
    const __m128i shift1 = _mm_slli_si128(sum0, 8);
    // a | a + b | a + b + c | a + b + c + d
    const __m128i sum1 = _mm_add_epi8(sum0, shift1);
    const __m128i res = _mm_add_epi8(sum1, prev);
    _mm_storeu_si128((__m128i*)&out[i], res);
    // replicate prev output on the four lanes
    prev = _mm_shuffle_epi32(res, (3 << 0) | (3 << 2) | (3 << 4) | (3 << 6));
  }
  if (i != num_pixels) {
    VP8LPredictorsAdd_C[1](in + i, upper + i, num_pixels - i, out + i);
  }
}

// Macro that adds 32-bit integers from IN using mod 256 arithmetic
// per 8 bit channel.
#define GENERATE_PREDICTOR_1(X, IN)                                           \
static void PredictorAdd##X##_SSE2(const uint32_t* in, const uint32_t* upper, \
                                  int num_pixels, uint32_t* out) {            \
  int i;                                                                      \
  for (i = 0; i + 4 <= num_pixels; i += 4) {                                  \
    const __m128i src = _mm_loadu_si128((const __m128i*)&in[i]);              \
    const __m128i other = _mm_loadu_si128((const __m128i*)&(IN));             \
    const __m128i res = _mm_add_epi8(src, other);                             \
    _mm_storeu_si128((__m128i*)&out[i], res);                                 \
  }                                                                           \
  if (i != num_pixels) {                                                      \
    VP8LPredictorsAdd_C[(X)](in + i, upper + i, num_pixels - i, out + i);     \
  }                                                                           \
}

// Predictor2: Top.
GENERATE_PREDICTOR_1(2, upper[i])
// Predictor3: Top-right.
GENERATE_PREDICTOR_1(3, upper[i + 1])
// Predictor4: Top-left.
GENERATE_PREDICTOR_1(4, upper[i - 1])
#undef GENERATE_PREDICTOR_1

// Due to averages with integers, values cannot be accumulated in parallel for
// predictors 5 to 7.
GENERATE_PREDICTOR_ADD(Predictor5_SSE2, PredictorAdd5_SSE2)
GENERATE_PREDICTOR_ADD(Predictor6_SSE2, PredictorAdd6_SSE2)
GENERATE_PREDICTOR_ADD(Predictor7_SSE2, PredictorAdd7_SSE2)

#define GENERATE_PREDICTOR_2(X, IN)                                           \
static void PredictorAdd##X##_SSE2(const uint32_t* in, const uint32_t* upper, \
                                   int num_pixels, uint32_t* out) {           \
  int i;                                                                      \
  for (i = 0; i + 4 <= num_pixels; i += 4) {                                  \
    const __m128i Tother = _mm_loadu_si128((const __m128i*)&(IN));            \
    const __m128i T = _mm_loadu_si128((const __m128i*)&upper[i]);             \
    const __m128i src = _mm_loadu_si128((const __m128i*)&in[i]);              \
    __m128i avg, res;                                                         \
    Average2_m128i(&T, &Tother, &avg);                                        \
    res = _mm_add_epi8(avg, src);                                             \
    _mm_storeu_si128((__m128i*)&out[i], res);                                 \
  }                                                                           \
  if (i != num_pixels) {                                                      \
    VP8LPredictorsAdd_C[(X)](in + i, upper + i, num_pixels - i, out + i);     \
  }                                                                           \
}
// Predictor8: average TL T.
GENERATE_PREDICTOR_2(8, upper[i - 1])
// Predictor9: average T TR.
GENERATE_PREDICTOR_2(9, upper[i + 1])
#undef GENERATE_PREDICTOR_2

// Predictor10: average of (average of (L,TL), average of (T, TR)).
#define DO_PRED10(OUT) do {               \
  __m128i avgLTL, avg;                    \
  Average2_m128i(&L, &TL, &avgLTL);       \
  Average2_m128i(&avgTTR, &avgLTL, &avg); \
  L = _mm_add_epi8(avg, src);             \
  out[i + (OUT)] = _mm_cvtsi128_si32(L);  \
} while (0)

#define DO_PRED10_SHIFT do {                                  \
  /* Rotate the pre-computed values for the next iteration.*/ \
  avgTTR = _mm_srli_si128(avgTTR, 4);                         \
  TL = _mm_srli_si128(TL, 4);                                 \
  src = _mm_srli_si128(src, 4);                               \
} while (0)

static void PredictorAdd10_SSE2(const uint32_t* in, const uint32_t* upper,
                                int num_pixels, uint32_t* out) {
  int i;
  __m128i L = _mm_cvtsi32_si128(out[-1]);
  for (i = 0; i + 4 <= num_pixels; i += 4) {
    __m128i src = _mm_loadu_si128((const __m128i*)&in[i]);
    __m128i TL = _mm_loadu_si128((const __m128i*)&upper[i - 1]);
    const __m128i T = _mm_loadu_si128((const __m128i*)&upper[i]);
    const __m128i TR = _mm_loadu_si128((const __m128i*)&upper[i + 1]);
    __m128i avgTTR;
    Average2_m128i(&T, &TR, &avgTTR);
    DO_PRED10(0);
    DO_PRED10_SHIFT;
    DO_PRED10(1);
    DO_PRED10_SHIFT;
    DO_PRED10(2);
    DO_PRED10_SHIFT;
    DO_PRED10(3);
  }
  if (i != num_pixels) {
    VP8LPredictorsAdd_C[10](in + i, upper + i, num_pixels - i, out + i);
  }
}
#undef DO_PRED10
#undef DO_PRED10_SHIFT

// Predictor11: select.
#define DO_PRED11(OUT) do {                                            \
  const __m128i L_lo = _mm_unpacklo_epi32(L, T);                       \
  const __m128i TL_lo = _mm_unpacklo_epi32(TL, T);                     \
  const __m128i pb = _mm_sad_epu8(L_lo, TL_lo); /* pb = sum |L-TL|*/   \
  const __m128i mask = _mm_cmpgt_epi32(pb, pa);                        \
  const __m128i A = _mm_and_si128(mask, L);                            \
  const __m128i B = _mm_andnot_si128(mask, T);                         \
  const __m128i pred = _mm_or_si128(A, B); /* pred = (pa > b)? L : T*/ \
  L = _mm_add_epi8(src, pred);                                         \
  out[i + (OUT)] = _mm_cvtsi128_si32(L);                               \
} while (0)

#define DO_PRED11_SHIFT do {                                \
  /* Shift the pre-computed value for the next iteration.*/ \
  T = _mm_srli_si128(T, 4);                                 \
  TL = _mm_srli_si128(TL, 4);                               \
  src = _mm_srli_si128(src, 4);                             \
  pa = _mm_srli_si128(pa, 4);                               \
} while (0)

static void PredictorAdd11_SSE2(const uint32_t* in, const uint32_t* upper,
                                int num_pixels, uint32_t* out) {
  int i;
  __m128i pa;
  __m128i L = _mm_cvtsi32_si128(out[-1]);
  for (i = 0; i + 4 <= num_pixels; i += 4) {
    __m128i T = _mm_loadu_si128((const __m128i*)&upper[i]);
    __m128i TL = _mm_loadu_si128((const __m128i*)&upper[i - 1]);
    __m128i src = _mm_loadu_si128((const __m128i*)&in[i]);
    {
      // We can unpack with any value on the upper 32 bits, provided it's the
      // same on both operands (so that their sum of abs diff is zero). Here we
      // use T.
      const __m128i T_lo = _mm_unpacklo_epi32(T, T);
      const __m128i TL_lo = _mm_unpacklo_epi32(TL, T);
      const __m128i T_hi = _mm_unpackhi_epi32(T, T);
      const __m128i TL_hi = _mm_unpackhi_epi32(TL, T);
      const __m128i s_lo = _mm_sad_epu8(T_lo, TL_lo);
      const __m128i s_hi = _mm_sad_epu8(T_hi, TL_hi);
      pa = _mm_packs_epi32(s_lo, s_hi);  // pa = sum |T-TL|
    }
    DO_PRED11(0);
    DO_PRED11_SHIFT;
    DO_PRED11(1);
    DO_PRED11_SHIFT;
    DO_PRED11(2);
    DO_PRED11_SHIFT;
    DO_PRED11(3);
  }
  if (i != num_pixels) {
    VP8LPredictorsAdd_C[11](in + i, upper + i, num_pixels - i, out + i);
  }
}
#undef DO_PRED11
#undef DO_PRED11_SHIFT

// Predictor12: ClampedAddSubtractFull.
#define DO_PRED12(DIFF, LANE, OUT) do {            \
  const __m128i all = _mm_add_epi16(L, (DIFF));    \
  const __m128i alls = _mm_packus_epi16(all, all); \
  const __m128i res = _mm_add_epi8(src, alls);     \
  out[i + (OUT)] = _mm_cvtsi128_si32(res);         \
  L = _mm_unpacklo_epi8(res, zero);                \
} while (0)

#define DO_PRED12_SHIFT(DIFF, LANE) do {                    \
  /* Shift the pre-computed value for the next iteration.*/ \
  if ((LANE) == 0) (DIFF) = _mm_srli_si128((DIFF), 8);      \
  src = _mm_srli_si128(src, 4);                             \
} while (0)

static void PredictorAdd12_SSE2(const uint32_t* in, const uint32_t* upper,
                                int num_pixels, uint32_t* out) {
  int i;
  const __m128i zero = _mm_setzero_si128();
  const __m128i L8 = _mm_cvtsi32_si128(out[-1]);
  __m128i L = _mm_unpacklo_epi8(L8, zero);
  for (i = 0; i + 4 <= num_pixels; i += 4) {
    // Load 4 pixels at a time.
    __m128i src = _mm_loadu_si128((const __m128i*)&in[i]);
    const __m128i T = _mm_loadu_si128((const __m128i*)&upper[i]);
    const __m128i T_lo = _mm_unpacklo_epi8(T, zero);
    const __m128i T_hi = _mm_unpackhi_epi8(T, zero);
    const __m128i TL = _mm_loadu_si128((const __m128i*)&upper[i - 1]);
    const __m128i TL_lo = _mm_unpacklo_epi8(TL, zero);
    const __m128i TL_hi = _mm_unpackhi_epi8(TL, zero);
    __m128i diff_lo = _mm_sub_epi16(T_lo, TL_lo);
    __m128i diff_hi = _mm_sub_epi16(T_hi, TL_hi);
    DO_PRED12(diff_lo, 0, 0);
    DO_PRED12_SHIFT(diff_lo, 0);
    DO_PRED12(diff_lo, 1, 1);
    DO_PRED12_SHIFT(diff_lo, 1);
    DO_PRED12(diff_hi, 0, 2);
    DO_PRED12_SHIFT(diff_hi, 0);
    DO_PRED12(diff_hi, 1, 3);
  }
  if (i != num_pixels) {
    VP8LPredictorsAdd_C[12](in + i, upper + i, num_pixels - i, out + i);
  }
}
#undef DO_PRED12
#undef DO_PRED12_SHIFT

// Due to averages with integers, values cannot be accumulated in parallel for
// predictors 13.
GENERATE_PREDICTOR_ADD(Predictor13_SSE2, PredictorAdd13_SSE2)

//------------------------------------------------------------------------------
// Subtract-Green Transform

static void AddGreenToBlueAndRed_SSE2(const uint32_t* const src, int num_pixels,
                                      uint32_t* dst) {
  int i;
  for (i = 0; i + 4 <= num_pixels; i += 4) {
    const __m128i in = _mm_loadu_si128((const __m128i*)&src[i]); // argb
    const __m128i A = _mm_srli_epi16(in, 8);     // 0 a 0 g
    const __m128i B = _mm_shufflelo_epi16(A, _MM_SHUFFLE(2, 2, 0, 0));
    const __m128i C = _mm_shufflehi_epi16(B, _MM_SHUFFLE(2, 2, 0, 0));  // 0g0g
    const __m128i out = _mm_add_epi8(in, C);
    _mm_storeu_si128((__m128i*)&dst[i], out);
  }
  // fallthrough and finish off with plain-C
  if (i != num_pixels) {
    VP8LAddGreenToBlueAndRed_C(src + i, num_pixels - i, dst + i);
  }
}

//------------------------------------------------------------------------------
// Color Transform

static void TransformColorInverse_SSE2(const VP8LMultipliers* const m,
                                       const uint32_t* const src,
                                       int num_pixels, uint32_t* dst) {
// sign-extended multiplying constants, pre-shifted by 5.
#define CST(X)  (((int16_t)(m->X << 8)) >> 5)   // sign-extend
#define MK_CST_16(HI, LO) \
  _mm_set1_epi32((int)(((uint32_t)(HI) << 16) | ((LO) & 0xffff)))
  const __m128i mults_rb = MK_CST_16(CST(green_to_red_), CST(green_to_blue_));
  const __m128i mults_b2 = MK_CST_16(CST(red_to_blue_), 0);
#undef MK_CST_16
#undef CST
  const __m128i mask_ag = _mm_set1_epi32(0xff00ff00);  // alpha-green masks
  int i;
  for (i = 0; i + 4 <= num_pixels; i += 4) {
    const __m128i in = _mm_loadu_si128((const __m128i*)&src[i]); // argb
    const __m128i A = _mm_and_si128(in, mask_ag);     // a   0   g   0
    const __m128i B = _mm_shufflelo_epi16(A, _MM_SHUFFLE(2, 2, 0, 0));
    const __m128i C = _mm_shufflehi_epi16(B, _MM_SHUFFLE(2, 2, 0, 0));  // g0g0
    const __m128i D = _mm_mulhi_epi16(C, mults_rb);    // x dr  x db1
    const __m128i E = _mm_add_epi8(in, D);             // x r'  x   b'
    const __m128i F = _mm_slli_epi16(E, 8);            // r' 0   b' 0
    const __m128i G = _mm_mulhi_epi16(F, mults_b2);    // x db2  0  0
    const __m128i H = _mm_srli_epi32(G, 8);            // 0  x db2  0
    const __m128i I = _mm_add_epi8(H, F);              // r' x  b'' 0
    const __m128i J = _mm_srli_epi16(I, 8);            // 0  r'  0  b''
    const __m128i out = _mm_or_si128(J, A);
    _mm_storeu_si128((__m128i*)&dst[i], out);
  }
  // Fall-back to C-version for left-overs.
  if (i != num_pixels) {
    VP8LTransformColorInverse_C(m, src + i, num_pixels - i, dst + i);
  }
}

//------------------------------------------------------------------------------
// Color-space conversion functions

static void ConvertBGRAToRGB_SSE2(const uint32_t* src, int num_pixels,
                                  uint8_t* dst) {
  const __m128i* in = (const __m128i*)src;
  __m128i* out = (__m128i*)dst;

  while (num_pixels >= 32) {
    // Load the BGRA buffers.
    __m128i in0 = _mm_loadu_si128(in + 0);
    __m128i in1 = _mm_loadu_si128(in + 1);
    __m128i in2 = _mm_loadu_si128(in + 2);
    __m128i in3 = _mm_loadu_si128(in + 3);
    __m128i in4 = _mm_loadu_si128(in + 4);
    __m128i in5 = _mm_loadu_si128(in + 5);
    __m128i in6 = _mm_loadu_si128(in + 6);
    __m128i in7 = _mm_loadu_si128(in + 7);
    VP8L32bToPlanar_SSE2(&in0, &in1, &in2, &in3);
    VP8L32bToPlanar_SSE2(&in4, &in5, &in6, &in7);
    // At this points, in1/in5 contains red only, in2/in6 green only ...
    // Pack the colors in 24b RGB.
    VP8PlanarTo24b_SSE2(&in1, &in5, &in2, &in6, &in3, &in7);
    _mm_storeu_si128(out + 0, in1);
    _mm_storeu_si128(out + 1, in5);
    _mm_storeu_si128(out + 2, in2);
    _mm_storeu_si128(out + 3, in6);
    _mm_storeu_si128(out + 4, in3);
    _mm_storeu_si128(out + 5, in7);
    in += 8;
    out += 6;
    num_pixels -= 32;
  }
  // left-overs
  if (num_pixels > 0) {
    VP8LConvertBGRAToRGB_C((const uint32_t*)in, num_pixels, (uint8_t*)out);
  }
}

static void ConvertBGRAToRGBA_SSE2(const uint32_t* src,
                                   int num_pixels, uint8_t* dst) {
  const __m128i red_blue_mask = _mm_set1_epi32(0x00ff00ffu);
  const __m128i* in = (const __m128i*)src;
  __m128i* out = (__m128i*)dst;
  while (num_pixels >= 8) {
    const __m128i A1 = _mm_loadu_si128(in++);
    const __m128i A2 = _mm_loadu_si128(in++);
    const __m128i B1 = _mm_and_si128(A1, red_blue_mask);     // R 0 B 0
    const __m128i B2 = _mm_and_si128(A2, red_blue_mask);     // R 0 B 0
    const __m128i C1 = _mm_andnot_si128(red_blue_mask, A1);  // 0 G 0 A
    const __m128i C2 = _mm_andnot_si128(red_blue_mask, A2);  // 0 G 0 A
    const __m128i D1 = _mm_shufflelo_epi16(B1, _MM_SHUFFLE(2, 3, 0, 1));
    const __m128i D2 = _mm_shufflelo_epi16(B2, _MM_SHUFFLE(2, 3, 0, 1));
    const __m128i E1 = _mm_shufflehi_epi16(D1, _MM_SHUFFLE(2, 3, 0, 1));
    const __m128i E2 = _mm_shufflehi_epi16(D2, _MM_SHUFFLE(2, 3, 0, 1));
    const __m128i F1 = _mm_or_si128(E1, C1);
    const __m128i F2 = _mm_or_si128(E2, C2);
    _mm_storeu_si128(out++, F1);
    _mm_storeu_si128(out++, F2);
    num_pixels -= 8;
  }
  // left-overs
  if (num_pixels > 0) {
    VP8LConvertBGRAToRGBA_C((const uint32_t*)in, num_pixels, (uint8_t*)out);
  }
}

static void ConvertBGRAToRGBA4444_SSE2(const uint32_t* src,
                                       int num_pixels, uint8_t* dst) {
  const __m128i mask_0x0f = _mm_set1_epi8(0x0f);
  const __m128i mask_0xf0 = _mm_set1_epi8(0xf0);
  const __m128i* in = (const __m128i*)src;
  __m128i* out = (__m128i*)dst;
  while (num_pixels >= 8) {
    const __m128i bgra0 = _mm_loadu_si128(in++);     // bgra0|bgra1|bgra2|bgra3
    const __m128i bgra4 = _mm_loadu_si128(in++);     // bgra4|bgra5|bgra6|bgra7
    const __m128i v0l = _mm_unpacklo_epi8(bgra0, bgra4);  // b0b4g0g4r0r4a0a4...
    const __m128i v0h = _mm_unpackhi_epi8(bgra0, bgra4);  // b2b6g2g6r2r6a2a6...
    const __m128i v1l = _mm_unpacklo_epi8(v0l, v0h);    // b0b2b4b6g0g2g4g6...
    const __m128i v1h = _mm_unpackhi_epi8(v0l, v0h);    // b1b3b5b7g1g3g5g7...
    const __m128i v2l = _mm_unpacklo_epi8(v1l, v1h);    // b0...b7 | g0...g7
    const __m128i v2h = _mm_unpackhi_epi8(v1l, v1h);    // r0...r7 | a0...a7
    const __m128i ga0 = _mm_unpackhi_epi64(v2l, v2h);   // g0...g7 | a0...a7
    const __m128i rb0 = _mm_unpacklo_epi64(v2h, v2l);   // r0...r7 | b0...b7
    const __m128i ga1 = _mm_srli_epi16(ga0, 4);         // g0-|g1-|...|a6-|a7-
    const __m128i rb1 = _mm_and_si128(rb0, mask_0xf0);  // -r0|-r1|...|-b6|-a7
    const __m128i ga2 = _mm_and_si128(ga1, mask_0x0f);  // g0-|g1-|...|a6-|a7-
    const __m128i rgba0 = _mm_or_si128(ga2, rb1);       // rg0..rg7 | ba0..ba7
    const __m128i rgba1 = _mm_srli_si128(rgba0, 8);     // ba0..ba7 | 0
#if (WEBP_SWAP_16BIT_CSP == 1)
    const __m128i rgba = _mm_unpacklo_epi8(rgba1, rgba0);  // barg0...barg7
#else
    const __m128i rgba = _mm_unpacklo_epi8(rgba0, rgba1);  // rgba0...rgba7
#endif
    _mm_storeu_si128(out++, rgba);
    num_pixels -= 8;
  }
  // left-overs
  if (num_pixels > 0) {
    VP8LConvertBGRAToRGBA4444_C((const uint32_t*)in, num_pixels, (uint8_t*)out);
  }
}

static void ConvertBGRAToRGB565_SSE2(const uint32_t* src,
                                     int num_pixels, uint8_t* dst) {
  const __m128i mask_0xe0 = _mm_set1_epi8(0xe0);
  const __m128i mask_0xf8 = _mm_set1_epi8(0xf8);
  const __m128i mask_0x07 = _mm_set1_epi8(0x07);
  const __m128i* in = (const __m128i*)src;
  __m128i* out = (__m128i*)dst;
  while (num_pixels >= 8) {
    const __m128i bgra0 = _mm_loadu_si128(in++);     // bgra0|bgra1|bgra2|bgra3
    const __m128i bgra4 = _mm_loadu_si128(in++);     // bgra4|bgra5|bgra6|bgra7
    const __m128i v0l = _mm_unpacklo_epi8(bgra0, bgra4);  // b0b4g0g4r0r4a0a4...
    const __m128i v0h = _mm_unpackhi_epi8(bgra0, bgra4);  // b2b6g2g6r2r6a2a6...
    const __m128i v1l = _mm_unpacklo_epi8(v0l, v0h);      // b0b2b4b6g0g2g4g6...
    const __m128i v1h = _mm_unpackhi_epi8(v0l, v0h);      // b1b3b5b7g1g3g5g7...
    const __m128i v2l = _mm_unpacklo_epi8(v1l, v1h);      // b0...b7 | g0...g7
    const __m128i v2h = _mm_unpackhi_epi8(v1l, v1h);      // r0...r7 | a0...a7
    const __m128i ga0 = _mm_unpackhi_epi64(v2l, v2h);     // g0...g7 | a0...a7
    const __m128i rb0 = _mm_unpacklo_epi64(v2h, v2l);     // r0...r7 | b0...b7
    const __m128i rb1 = _mm_and_si128(rb0, mask_0xf8);    // -r0..-r7|-b0..-b7
    const __m128i g_lo1 = _mm_srli_epi16(ga0, 5);
    const __m128i g_lo2 = _mm_and_si128(g_lo1, mask_0x07);  // g0-...g7-|xx (3b)
    const __m128i g_hi1 = _mm_slli_epi16(ga0, 3);
    const __m128i g_hi2 = _mm_and_si128(g_hi1, mask_0xe0);  // -g0...-g7|xx (3b)
    const __m128i b0 = _mm_srli_si128(rb1, 8);              // -b0...-b7|0
    const __m128i rg1 = _mm_or_si128(rb1, g_lo2);           // gr0...gr7|xx
    const __m128i b1 = _mm_srli_epi16(b0, 3);
    const __m128i gb1 = _mm_or_si128(b1, g_hi2);            // bg0...bg7|xx
#if (WEBP_SWAP_16BIT_CSP == 1)
    const __m128i rgba = _mm_unpacklo_epi8(gb1, rg1);     // rggb0...rggb7
#else
    const __m128i rgba = _mm_unpacklo_epi8(rg1, gb1);     // bgrb0...bgrb7
#endif
    _mm_storeu_si128(out++, rgba);
    num_pixels -= 8;
  }
  // left-overs
  if (num_pixels > 0) {
    VP8LConvertBGRAToRGB565_C((const uint32_t*)in, num_pixels, (uint8_t*)out);
  }
}

static void ConvertBGRAToBGR_SSE2(const uint32_t* src,
                                  int num_pixels, uint8_t* dst) {
  const __m128i mask_l = _mm_set_epi32(0, 0x00ffffff, 0, 0x00ffffff);
  const __m128i mask_h = _mm_set_epi32(0x00ffffff, 0, 0x00ffffff, 0);
  const __m128i* in = (const __m128i*)src;
  const uint8_t* const end = dst + num_pixels * 3;
  // the last storel_epi64 below writes 8 bytes starting at offset 18
  while (dst + 26 <= end) {
    const __m128i bgra0 = _mm_loadu_si128(in++);     // bgra0|bgra1|bgra2|bgra3
    const __m128i bgra4 = _mm_loadu_si128(in++);     // bgra4|bgra5|bgra6|bgra7
    const __m128i a0l = _mm_and_si128(bgra0, mask_l);   // bgr0|0|bgr0|0
    const __m128i a4l = _mm_and_si128(bgra4, mask_l);   // bgr0|0|bgr0|0
    const __m128i a0h = _mm_and_si128(bgra0, mask_h);   // 0|bgr0|0|bgr0
    const __m128i a4h = _mm_and_si128(bgra4, mask_h);   // 0|bgr0|0|bgr0
    const __m128i b0h = _mm_srli_epi64(a0h, 8);         // 000b|gr00|000b|gr00
    const __m128i b4h = _mm_srli_epi64(a4h, 8);         // 000b|gr00|000b|gr00
    const __m128i c0 = _mm_or_si128(a0l, b0h);          // rgbrgb00|rgbrgb00
    const __m128i c4 = _mm_or_si128(a4l, b4h);          // rgbrgb00|rgbrgb00
    const __m128i c2 = _mm_srli_si128(c0, 8);
    const __m128i c6 = _mm_srli_si128(c4, 8);
    _mm_storel_epi64((__m128i*)(dst +   0), c0);
    _mm_storel_epi64((__m128i*)(dst +   6), c2);
    _mm_storel_epi64((__m128i*)(dst +  12), c4);
    _mm_storel_epi64((__m128i*)(dst +  18), c6);
    dst += 24;
    num_pixels -= 8;
  }
  // left-overs
  if (num_pixels > 0) {
    VP8LConvertBGRAToBGR_C((const uint32_t*)in, num_pixels, dst);
  }
}

//------------------------------------------------------------------------------
// Entry point

extern void VP8LDspInitSSE2(void);

WEBP_TSAN_IGNORE_FUNCTION void VP8LDspInitSSE2(void) {
  VP8LPredictors[5] = Predictor5_SSE2;
  VP8LPredictors[6] = Predictor6_SSE2;
  VP8LPredictors[7] = Predictor7_SSE2;
  VP8LPredictors[8] = Predictor8_SSE2;
  VP8LPredictors[9] = Predictor9_SSE2;
  VP8LPredictors[10] = Predictor10_SSE2;
  VP8LPredictors[11] = Predictor11_SSE2;
  VP8LPredictors[12] = Predictor12_SSE2;
  VP8LPredictors[13] = Predictor13_SSE2;

  VP8LPredictorsAdd[0] = PredictorAdd0_SSE2;
  VP8LPredictorsAdd[1] = PredictorAdd1_SSE2;
  VP8LPredictorsAdd[2] = PredictorAdd2_SSE2;
  VP8LPredictorsAdd[3] = PredictorAdd3_SSE2;
  VP8LPredictorsAdd[4] = PredictorAdd4_SSE2;
  VP8LPredictorsAdd[5] = PredictorAdd5_SSE2;
  VP8LPredictorsAdd[6] = PredictorAdd6_SSE2;
  VP8LPredictorsAdd[7] = PredictorAdd7_SSE2;
  VP8LPredictorsAdd[8] = PredictorAdd8_SSE2;
  VP8LPredictorsAdd[9] = PredictorAdd9_SSE2;
  VP8LPredictorsAdd[10] = PredictorAdd10_SSE2;
  VP8LPredictorsAdd[11] = PredictorAdd11_SSE2;
  VP8LPredictorsAdd[12] = PredictorAdd12_SSE2;
  VP8LPredictorsAdd[13] = PredictorAdd13_SSE2;

  VP8LAddGreenToBlueAndRed = AddGreenToBlueAndRed_SSE2;
  VP8LTransformColorInverse = TransformColorInverse_SSE2;

  VP8LConvertBGRAToRGB = ConvertBGRAToRGB_SSE2;
  VP8LConvertBGRAToRGBA = ConvertBGRAToRGBA_SSE2;
  VP8LConvertBGRAToRGBA4444 = ConvertBGRAToRGBA4444_SSE2;
  VP8LConvertBGRAToRGB565 = ConvertBGRAToRGB565_SSE2;
  VP8LConvertBGRAToBGR = ConvertBGRAToBGR_SSE2;
}

#else  // !WEBP_USE_SSE2

WEBP_DSP_INIT_STUB(VP8LDspInitSSE2)

#endif  // WEBP_USE_SSE2