1 /*
2 * Copyright (c) 2020, Alliance for Open Media. All rights reserved.
3 *
4 * This source code is subject to the terms of the BSD 2 Clause License and
5 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
6 * was not distributed with this source code in the LICENSE file, you can
7 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
8 * Media Patent License 1.0 was not distributed with this source code in the
9 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
10 */
11
12 #include <arm_neon.h>
13
14 #include "aom_dsp/txfm_common.h"
15 #include "config/av1_rtcd.h"
16
transpose4x4(int16x8_t in[2],int16x4_t out[4])17 static void transpose4x4(int16x8_t in[2], int16x4_t out[4]) {
18 int32x4x2_t b0 =
19 vtrnq_s32(vreinterpretq_s32_s16(in[0]), vreinterpretq_s32_s16(in[1]));
20 int16x4x2_t c0 = vtrn_s16(vreinterpret_s16_s32(vget_low_s32(b0.val[0])),
21 vreinterpret_s16_s32(vget_high_s32(b0.val[0])));
22 int16x4x2_t c1 = vtrn_s16(vreinterpret_s16_s32(vget_low_s32(b0.val[1])),
23 vreinterpret_s16_s32(vget_high_s32(b0.val[1])));
24 out[0] = c0.val[0];
25 out[1] = c0.val[1];
26 out[2] = c1.val[0];
27 out[3] = c1.val[1];
28 }
29
av1_fwht4x4_neon(const int16_t * input,tran_low_t * output,int stride)30 void av1_fwht4x4_neon(const int16_t *input, tran_low_t *output, int stride) {
31 // Load the 4x4 source in transposed form.
32 int16x4_t a1, b1, c1, d1, e;
33 a1 = vld1_s16(&input[0]);
34 b1 = vld1_s16(&input[1 * stride]);
35 c1 = vld1_s16(&input[2 * stride]);
36 d1 = vld1_s16(&input[3 * stride]);
37
38 // WHT.
39
40 // Row transforms.
41 a1 = vadd_s16(a1, b1);
42 d1 = vsub_s16(d1, c1);
43 e = vhsub_s16(a1, d1);
44 b1 = vsub_s16(e, b1);
45 c1 = vsub_s16(e, c1);
46 a1 = vsub_s16(a1, c1);
47 d1 = vadd_s16(d1, b1);
48
49 int16x8_t x[2];
50 x[0] = vcombine_s16(a1, c1);
51 x[1] = vcombine_s16(d1, b1);
52
53 int16x4_t s[4];
54 transpose4x4(x, s);
55
56 a1 = s[0];
57 b1 = s[1];
58 c1 = s[2];
59 d1 = s[3];
60
61 // Row transforms.
62 a1 = vadd_s16(a1, b1);
63 d1 = vsub_s16(d1, c1);
64 e = vhsub_s16(a1, d1);
65 b1 = vsub_s16(e, b1);
66 c1 = vsub_s16(e, c1);
67 a1 = vsub_s16(a1, c1);
68 d1 = vadd_s16(d1, b1);
69
70 vst1q_s32(&output[0], vshll_n_s16(a1, UNIT_QUANT_SHIFT));
71 vst1q_s32(&output[4], vshll_n_s16(c1, UNIT_QUANT_SHIFT));
72 vst1q_s32(&output[8], vshll_n_s16(d1, UNIT_QUANT_SHIFT));
73 vst1q_s32(&output[12], vshll_n_s16(b1, UNIT_QUANT_SHIFT));
74 }
75