1 /*
2 * Copyright (c) 2014 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 #include <arm_neon.h>
12
13 #include "./vp8_rtcd.h"
14
15 static const int16_t cospi8sqrt2minus1 = 20091;
16 // 35468 exceeds INT16_MAX and gets converted to a negative number. Because of
17 // the way it is used in vqdmulh, where the result is doubled, it can be divided
18 // by 2 beforehand. This saves compensating for the negative value as well as
19 // shifting the result.
20 static const int16_t sinpi8sqrt2 = 35468 >> 1;
21
vp8_dequant_idct_add_neon(int16_t * input,int16_t * dq,unsigned char * dst,int stride)22 void vp8_dequant_idct_add_neon(int16_t *input, int16_t *dq, unsigned char *dst,
23 int stride) {
24 unsigned char *dst0;
25 int32x2_t d14, d15;
26 int16x4_t d2, d3, d4, d5, d10, d11, d12, d13;
27 int16x8_t q1, q2, q3, q4, q5, q6;
28 int16x8_t qEmpty = vdupq_n_s16(0);
29 int32x2x2_t d2tmp0, d2tmp1;
30 int16x4x2_t d2tmp2, d2tmp3;
31
32 d14 = d15 = vdup_n_s32(0);
33
34 // load input
35 q3 = vld1q_s16(input);
36 vst1q_s16(input, qEmpty);
37 input += 8;
38 q4 = vld1q_s16(input);
39 vst1q_s16(input, qEmpty);
40
41 // load dq
42 q5 = vld1q_s16(dq);
43 dq += 8;
44 q6 = vld1q_s16(dq);
45
46 // load src from dst
47 dst0 = dst;
48 d14 = vld1_lane_s32((const int32_t *)dst0, d14, 0);
49 dst0 += stride;
50 d14 = vld1_lane_s32((const int32_t *)dst0, d14, 1);
51 dst0 += stride;
52 d15 = vld1_lane_s32((const int32_t *)dst0, d15, 0);
53 dst0 += stride;
54 d15 = vld1_lane_s32((const int32_t *)dst0, d15, 1);
55
56 q1 = vreinterpretq_s16_u16(
57 vmulq_u16(vreinterpretq_u16_s16(q3), vreinterpretq_u16_s16(q5)));
58 q2 = vreinterpretq_s16_u16(
59 vmulq_u16(vreinterpretq_u16_s16(q4), vreinterpretq_u16_s16(q6)));
60
61 d12 = vqadd_s16(vget_low_s16(q1), vget_low_s16(q2));
62 d13 = vqsub_s16(vget_low_s16(q1), vget_low_s16(q2));
63
64 q2 = vcombine_s16(vget_high_s16(q1), vget_high_s16(q2));
65
66 q3 = vqdmulhq_n_s16(q2, sinpi8sqrt2);
67 q4 = vqdmulhq_n_s16(q2, cospi8sqrt2minus1);
68
69 q4 = vshrq_n_s16(q4, 1);
70
71 q4 = vqaddq_s16(q4, q2);
72
73 d10 = vqsub_s16(vget_low_s16(q3), vget_high_s16(q4));
74 d11 = vqadd_s16(vget_high_s16(q3), vget_low_s16(q4));
75
76 d2 = vqadd_s16(d12, d11);
77 d3 = vqadd_s16(d13, d10);
78 d4 = vqsub_s16(d13, d10);
79 d5 = vqsub_s16(d12, d11);
80
81 d2tmp0 = vtrn_s32(vreinterpret_s32_s16(d2), vreinterpret_s32_s16(d4));
82 d2tmp1 = vtrn_s32(vreinterpret_s32_s16(d3), vreinterpret_s32_s16(d5));
83 d2tmp2 = vtrn_s16(vreinterpret_s16_s32(d2tmp0.val[0]),
84 vreinterpret_s16_s32(d2tmp1.val[0]));
85 d2tmp3 = vtrn_s16(vreinterpret_s16_s32(d2tmp0.val[1]),
86 vreinterpret_s16_s32(d2tmp1.val[1]));
87
88 // loop 2
89 q2 = vcombine_s16(d2tmp2.val[1], d2tmp3.val[1]);
90
91 q3 = vqdmulhq_n_s16(q2, sinpi8sqrt2);
92 q4 = vqdmulhq_n_s16(q2, cospi8sqrt2minus1);
93
94 d12 = vqadd_s16(d2tmp2.val[0], d2tmp3.val[0]);
95 d13 = vqsub_s16(d2tmp2.val[0], d2tmp3.val[0]);
96
97 q4 = vshrq_n_s16(q4, 1);
98
99 q4 = vqaddq_s16(q4, q2);
100
101 d10 = vqsub_s16(vget_low_s16(q3), vget_high_s16(q4));
102 d11 = vqadd_s16(vget_high_s16(q3), vget_low_s16(q4));
103
104 d2 = vqadd_s16(d12, d11);
105 d3 = vqadd_s16(d13, d10);
106 d4 = vqsub_s16(d13, d10);
107 d5 = vqsub_s16(d12, d11);
108
109 d2 = vrshr_n_s16(d2, 3);
110 d3 = vrshr_n_s16(d3, 3);
111 d4 = vrshr_n_s16(d4, 3);
112 d5 = vrshr_n_s16(d5, 3);
113
114 d2tmp0 = vtrn_s32(vreinterpret_s32_s16(d2), vreinterpret_s32_s16(d4));
115 d2tmp1 = vtrn_s32(vreinterpret_s32_s16(d3), vreinterpret_s32_s16(d5));
116 d2tmp2 = vtrn_s16(vreinterpret_s16_s32(d2tmp0.val[0]),
117 vreinterpret_s16_s32(d2tmp1.val[0]));
118 d2tmp3 = vtrn_s16(vreinterpret_s16_s32(d2tmp0.val[1]),
119 vreinterpret_s16_s32(d2tmp1.val[1]));
120
121 q1 = vcombine_s16(d2tmp2.val[0], d2tmp2.val[1]);
122 q2 = vcombine_s16(d2tmp3.val[0], d2tmp3.val[1]);
123
124 q1 = vreinterpretq_s16_u16(
125 vaddw_u8(vreinterpretq_u16_s16(q1), vreinterpret_u8_s32(d14)));
126 q2 = vreinterpretq_s16_u16(
127 vaddw_u8(vreinterpretq_u16_s16(q2), vreinterpret_u8_s32(d15)));
128
129 d14 = vreinterpret_s32_u8(vqmovun_s16(q1));
130 d15 = vreinterpret_s32_u8(vqmovun_s16(q2));
131
132 dst0 = dst;
133 vst1_lane_s32((int32_t *)dst0, d14, 0);
134 dst0 += stride;
135 vst1_lane_s32((int32_t *)dst0, d14, 1);
136 dst0 += stride;
137 vst1_lane_s32((int32_t *)dst0, d15, 0);
138 dst0 += stride;
139 vst1_lane_s32((int32_t *)dst0, d15, 1);
140 return;
141 }
142