1 /*
2 * Copyright (c) 2023, 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 #include <assert.h>
14
15 #include "config/aom_config.h"
16 #include "config/aom_dsp_rtcd.h"
17 #include "aom/aom_integer.h"
18 #include "aom_dsp/arm/aom_neon_sve_bridge.h"
19 #include "aom_dsp/arm/mem_neon.h"
20 #include "aom_ports/mem.h"
21
aom_vector_var_sve(const int16_t * ref,const int16_t * src,int bwl)22 int aom_vector_var_sve(const int16_t *ref, const int16_t *src, int bwl) {
23 assert(bwl >= 2 && bwl <= 5);
24 int width = 4 << bwl;
25
26 int64x2_t sse_s64[2] = { vdupq_n_s64(0), vdupq_n_s64(0) };
27 int16x8_t v_mean[2] = { vdupq_n_s16(0), vdupq_n_s16(0) };
28
29 do {
30 int16x8_t r0 = vld1q_s16(ref);
31 int16x8_t s0 = vld1q_s16(src);
32
33 // diff: dynamic range [-510, 510] 10 (signed) bits.
34 int16x8_t diff0 = vsubq_s16(r0, s0);
35 // v_mean: dynamic range 16 * diff -> [-8160, 8160], 14 (signed) bits.
36 v_mean[0] = vaddq_s16(v_mean[0], diff0);
37
38 // v_sse: dynamic range 2 * 16 * diff^2 -> [0, 8,323,200], 24 (signed) bits.
39 sse_s64[0] = aom_sdotq_s16(sse_s64[0], diff0, diff0);
40
41 int16x8_t r1 = vld1q_s16(ref + 8);
42 int16x8_t s1 = vld1q_s16(src + 8);
43
44 // diff: dynamic range [-510, 510] 10 (signed) bits.
45 int16x8_t diff1 = vsubq_s16(r1, s1);
46 // v_mean: dynamic range 16 * diff -> [-8160, 8160], 14 (signed) bits.
47 v_mean[1] = vaddq_s16(v_mean[1], diff1);
48
49 // v_sse: dynamic range 2 * 16 * diff^2 -> [0, 8,323,200], 24 (signed) bits.
50 sse_s64[1] = aom_sdotq_s16(sse_s64[1], diff1, diff1);
51
52 ref += 16;
53 src += 16;
54 width -= 16;
55 } while (width != 0);
56
57 // Dynamic range [0, 65280], 16 (unsigned) bits.
58 const uint32_t mean_abs = abs(vaddlvq_s16(vaddq_s16(v_mean[0], v_mean[1])));
59 const int64_t sse = vaddvq_s64(vaddq_s64(sse_s64[0], sse_s64[1]));
60
61 // (mean_abs * mean_abs): dynamic range 32 (unsigned) bits.
62 return (int)(sse - ((mean_abs * mean_abs) >> (bwl + 2)));
63 }
64