1/* Compute sine of argument.
2 Copyright (C) 2018-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <stdint.h>
20#include <math.h>
21#include <math-barriers.h>
22#include <libm-alias-float.h>
23#include "math_config.h"
24#include "s_sincosf.h"
25
26#ifndef SECTION
27# define SECTION
28#endif
29
30#ifndef SINF
31# define SINF_FUNC __sinf
32#else
33# define SINF_FUNC SINF
34#endif
35
36/* Fast sinf implementation. Worst-case ULP is 0.5607, maximum relative
37 error is 0.5303 * 2^-23. A single-step range reduction is used for
38 small values. Large inputs have their range reduced using fast integer
39 arithmetic.
40*/
41float
42SECTION
43SINF_FUNC (float y)
44{
45 double x = y;
46 double s;
47 int n;
48 const sincos_t *p = &__sincosf_table[0];
49
50 if (abstop12 (y) < abstop12 (pio4))
51 {
52 s = x * x;
53
54 if (__glibc_unlikely (abstop12 (y) < abstop12 (0x1p-12f)))
55 {
56 /* Force underflow for tiny y. */
57 if (__glibc_unlikely (abstop12 (y) < abstop12 (0x1p-126f)))
58 math_force_eval ((float)s);
59 return y;
60 }
61
62 return sinf_poly (x, s, p, 0);
63 }
64 else if (__glibc_likely (abstop12 (y) < abstop12 (120.0f)))
65 {
66 x = reduce_fast (x, p, &n);
67
68 /* Setup the signs for sin and cos. */
69 s = p->sign[n & 3];
70
71 if (n & 2)
72 p = &__sincosf_table[1];
73
74 return sinf_poly (x * s, x * x, p, n);
75 }
76 else if (abstop12 (y) < abstop12 (INFINITY))
77 {
78 uint32_t xi = asuint (y);
79 int sign = xi >> 31;
80
81 x = reduce_large (xi, &n);
82
83 /* Setup signs for sin and cos - include original sign. */
84 s = p->sign[(n + sign) & 3];
85
86 if ((n + sign) & 2)
87 p = &__sincosf_table[1];
88
89 return sinf_poly (x * s, x * x, p, n);
90 }
91 else
92 return __math_invalidf (y);
93}
94
95#ifndef SINF
96libm_alias_float (__sin, sin)
97#endif
98