1/*
2 *  Copyright (c) 2017 The WebM project authors. All Rights Reserved.
3 *
4 *  Use of this source code is governed by a BSD-style license
5 *  that can be found in the LICENSE file in the root of the source
6 *  tree. An additional intellectual property rights grant can be found
7 *  in the file PATENTS.  All contributing project authors may
8 *  be found in the AUTHORS file in the root of the source tree.
9 */
10
11#ifndef VPX_DSP_PPC_TRANSPOSE_VSX_H_
12#define VPX_DSP_PPC_TRANSPOSE_VSX_H_
13
14#include "./vpx_config.h"
15#include "vpx_dsp/ppc/types_vsx.h"
16
17static INLINE void vpx_transpose_s16_8x8(int16x8_t v[8]) {
18  // d = vec_mergeh(a,b):
19  // The even elements of the result are obtained left-to-right,
20  // from the high elements of a.
21  // The odd elements of the result are obtained left-to-right,
22  // from the high elements of b.
23  //
24  // d = vec_mergel(a,b):
25  // The even elements of the result are obtained left-to-right,
26  // from the low elements of a.
27  // The odd elements of the result are obtained left-to-right,
28  // from the low elements of b.
29
30  // Example, starting with:
31  // v[0]: 00 01 02 03 04 05 06 07
32  // v[1]: 10 11 12 13 14 15 16 17
33  // v[2]: 20 21 22 23 24 25 26 27
34  // v[3]: 30 31 32 33 34 35 36 37
35  // v[4]: 40 41 42 43 44 45 46 47
36  // v[5]: 50 51 52 53 54 55 56 57
37  // v[6]: 60 61 62 63 64 65 66 67
38  // v[7]: 70 71 72 73 74 75 76 77
39
40  int16x8_t b0, b1, b2, b3, b4, b5, b6, b7;
41  int16x8_t c0, c1, c2, c3, c4, c5, c6, c7;
42
43  b0 = vec_mergeh(v[0], v[4]);
44  b1 = vec_mergel(v[0], v[4]);
45  b2 = vec_mergeh(v[1], v[5]);
46  b3 = vec_mergel(v[1], v[5]);
47  b4 = vec_mergeh(v[2], v[6]);
48  b5 = vec_mergel(v[2], v[6]);
49  b6 = vec_mergeh(v[3], v[7]);
50  b7 = vec_mergel(v[3], v[7]);
51
52  // After first merge operation
53  // b0: 00 40 01 41 02 42 03 43
54  // b1: 04 44 05 45 06 46 07 47
55  // b2: 10 50 11 51 12 52 13 53
56  // b3: 14 54 15 55 16 56 17 57
57  // b4: 20 60 21 61 22 62 23 63
58  // b5: 24 64 25 65 26 66 27 67
59  // b6: 30 70 31 71 32 62 33 73
60  // b7: 34 74 35 75 36 76 37 77
61
62  c0 = vec_mergeh(b0, b4);
63  c1 = vec_mergel(b0, b4);
64  c2 = vec_mergeh(b1, b5);
65  c3 = vec_mergel(b1, b5);
66  c4 = vec_mergeh(b2, b6);
67  c5 = vec_mergel(b2, b6);
68  c6 = vec_mergeh(b3, b7);
69  c7 = vec_mergel(b3, b7);
70
71  // After second merge operation
72  // c0: 00 20 40 60 01 21 41 61
73  // c1: 02 22 42 62 03 23 43 63
74  // c2: 04 24 44 64 05 25 45 65
75  // c3: 06 26 46 66 07 27 47 67
76  // c4: 10 30 50 70 11 31 51 71
77  // c5: 12 32 52 72 13 33 53 73
78  // c6: 14 34 54 74 15 35 55 75
79  // c7: 16 36 56 76 17 37 57 77
80
81  v[0] = vec_mergeh(c0, c4);
82  v[1] = vec_mergel(c0, c4);
83  v[2] = vec_mergeh(c1, c5);
84  v[3] = vec_mergel(c1, c5);
85  v[4] = vec_mergeh(c2, c6);
86  v[5] = vec_mergel(c2, c6);
87  v[6] = vec_mergeh(c3, c7);
88  v[7] = vec_mergel(c3, c7);
89
90  // After last merge operation
91  // v[0]: 00 10 20 30 40 50 60 70
92  // v[1]: 01 11 21 31 41 51 61 71
93  // v[2]: 02 12 22 32 42 52 62 72
94  // v[3]: 03 13 23 33 43 53 63 73
95  // v[4]: 04 14 24 34 44 54 64 74
96  // v[5]: 05 15 25 35 45 55 65 75
97  // v[6]: 06 16 26 36 46 56 66 76
98  // v[7]: 07 17 27 37 47 57 67 77
99}
100
101#endif  // VPX_DSP_PPC_TRANSPOSE_VSX_H_
102