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
|
/*
* Copyright (C) 2012 Spreadtrum Communications Inc.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include "sin_cos.h"
#define SINCOS_BIT_31 (1 << 31)
#define SINCOS_BIT_30 (1 << 30)
#define SMULL(x, y) ((int64_t)(x) * (int64_t)(y))
static const uint32_t cossin_tbl[64] = {
0x3ffec42d, 0x00c90e90, 0x3ff4e5e0, 0x025b0caf,
0x3fe12acb, 0x03ecadcf, 0x3fc395f9, 0x057db403,
0x3f9c2bfb, 0x070de172, 0x3f6af2e3, 0x089cf867,
0x3f2ff24a, 0x0a2abb59, 0x3eeb3347, 0x0bb6ecef,
0x3e9cc076, 0x0d415013, 0x3e44a5ef, 0x0ec9a7f3,
0x3de2f148, 0x104fb80e, 0x3d77b192, 0x11d3443f,
0x3d02f757, 0x135410c3, 0x3c84d496, 0x14d1e242,
0x3bfd5cc4, 0x164c7ddd, 0x3b6ca4c4, 0x17c3a931,
0x3ad2c2e8, 0x19372a64, 0x3a2fcee8, 0x1aa6c82b,
0x3983e1e8, 0x1c1249d8, 0x38cf1669, 0x1d79775c,
0x3811884d, 0x1edc1953, 0x374b54ce, 0x2039f90f,
0x367c9a7e, 0x2192e09b, 0x35a5793c, 0x22e69ac8,
0x34c61236, 0x2434f332, 0x33de87de, 0x257db64c,
0x32eefdea, 0x26c0b162, 0x31f79948, 0x27fdb2a7,
0x30f8801f, 0x29348937, 0x2ff1d9c7, 0x2a650525,
0x2ee3cebe, 0x2b8ef77d, 0x2dce88aa, 0x2cb2324c
};
static int32_t sin_core(int32_t arc_q33, int32_t sign)
{
int32_t a, b, B;
int32_t sin_a, cos_a;
int32_t S1, S2, S3, S4, T1;
int32_t R = 0;
int32_t C1 = 0x6487ed51;
int32_t C2 = -715827882;
a = arc_q33 >> 25;
cos_a = cossin_tbl[2 * a];
sin_a = cossin_tbl[2 * a + 1];
cos_a ^= (sign >> 31);
sin_a ^= (sign >> 31);
a = a << 25;
b = arc_q33 - a;
b -= (1 << 24);
B = SMULL((b << 3), C1) >> 32;
T1 = SMULL(B, B) >> 32;
S1 = sin_a;
S2 = SMULL(sin_a, T1 >> 1) >> 32;
S3 = SMULL(cos_a, B) >> 32;
S4 = SMULL(T1, C2) >> 32;
S4 = SMULL(S3, S4) >> 32;
R = S1 - S2 + S3 + S4;
return R;
}
static int32_t cos_core(int32_t arc_q33, int32_t sign)
{
int32_t a, b, B;
int32_t sin_a, cos_a;
int32_t S1, S2, S3, S4, T1;
int32_t R = 0;
int32_t C1 = 0x6487ed51; //round(2 * PI * 2 ^ 28)
int32_t C2 = 0x2aaaaaab; //round(2^32/6)
a = arc_q33 >> 25;
cos_a = cossin_tbl[a * 2];
sin_a = cossin_tbl[a * 2 + 1];
cos_a ^= (sign >> 31);
sin_a ^= (sign >> 31);
a = a << 25;
b = arc_q33 - a;
b -= (1 << 24);
B = SMULL((b << 3), C1) >> 32;
T1 = SMULL(B, B) >> 32;
S1 = cos_a;
S2 = SMULL(cos_a, T1 >> 1) >> 32;
S3 = SMULL(sin_a, B) >> 32;
S4 = SMULL(T1, C2) >> 32;
S4 = SMULL(S3, S4) >> 32;
R = S1 - S2 - S3 + S4;
return R;
}
int32_t sin_32(int32_t n)
{
int32_t s = n & SINCOS_BIT_31;
n = n << 1;
if (0 == n) {
return 0;
}
if (SINCOS_BIT_31 == (n & SINCOS_BIT_31)) {
n &= ~SINCOS_BIT_31;
if (n < SINCOS_BIT_30) {
return cos_core(n, s);
} else if (n == SINCOS_BIT_30) {
n -= 1;
} else if (n > SINCOS_BIT_30) {
n = SINCOS_BIT_31 - n;
}
return sin_core(n, s);
} else {
if (n < SINCOS_BIT_30) {
return sin_core(n, s);
}
if (n == SINCOS_BIT_30) {
n -= 1;
} else if (n > SINCOS_BIT_30) {
n = SINCOS_BIT_31 - n;
}
return cos_core(n, s);
}
}
int32_t cos_32(int32_t n)
{
int32_t s = n & SINCOS_BIT_31;
n = n << 1;
if (n == SINCOS_BIT_31) {
return 0;
}
if (SINCOS_BIT_31 == (n & SINCOS_BIT_31)) {
n &= ~SINCOS_BIT_31;
if (n < SINCOS_BIT_30) {
return -sin_core(n, s);
} else if (n == SINCOS_BIT_30) {
n -= 1;
} else if (n > SINCOS_BIT_30) {
n = SINCOS_BIT_31 - n;
}
return -cos_core(n, s);
} else {
if (n < SINCOS_BIT_30) {
return cos_core(n, s);
}
if (n == SINCOS_BIT_30) {
n -= 1;
} else if (n > SINCOS_BIT_30) {
n = SINCOS_BIT_31 - n;
}
return sin_core(n, s);
}
}
|
