1/* Compute sine and cosine of argument.
2 Copyright (C) 2018-2022 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 <errno.h>
20#include <stdint.h>
21#include <math.h>
22#include <math-barriers.h>
23#include <libm-alias-float.h>
24#include "math_config.h"
25#include "s_sincosf.h"
26
27#ifndef SECTION
28# define SECTION
29#endif
30
31#ifndef SINCOSF
32# define SINCOSF_FUNC __sincosf
33#else
34# define SINCOSF_FUNC SINCOSF
35#endif
36
37/* Fast sincosf implementation. Worst-case ULP is 0.5607, maximum relative
38 error is 0.5303 * 2^-23. A single-step range reduction is used for
39 small values. Large inputs have their range reduced using fast integer
40 arithmetic. */
41void
42SECTION
43SINCOSF_FUNC (float y, float *sinp, float *cosp)
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 double x2 = 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)x2);
59 *sinp = y;
60 *cosp = 1.0f;
61 return;
62 }
63
64 sincosf_poly (x, x2, p, 0, sinp, cosp);
65 }
66 else if (abstop12 (y) < abstop12 (120.0f))
67 {
68 x = reduce_fast (x, p, &n);
69
70 /* Setup the signs for sin and cos. */
71 s = p->sign[n & 3];
72
73 if (n & 2)
74 p = &__sincosf_table[1];
75
76 sincosf_poly (x * s, x * x, p, n, sinp, cosp);
77 }
78 else if (__glibc_likely (abstop12 (y) < abstop12 (INFINITY)))
79 {
80 uint32_t xi = asuint (y);
81 int sign = xi >> 31;
82
83 x = reduce_large (xi, &n);
84
85 /* Setup signs for sin and cos - include original sign. */
86 s = p->sign[(n + sign) & 3];
87
88 if ((n + sign) & 2)
89 p = &__sincosf_table[1];
90
91 sincosf_poly (x * s, x * x, p, n, sinp, cosp);
92 }
93 else
94 {
95 /* Return NaN if Inf or NaN for both sin and cos. */
96 *sinp = *cosp = y - y;
97#if WANT_ERRNO
98 /* Needed to set errno for +-Inf, the add is a hack to work
99 around a gcc register allocation issue: just passing y
100 affects code generation in the fast path (PR86901). */
101 __math_invalidf (y + y);
102#endif
103 }
104}
105
106#ifndef SINCOSF
107libm_alias_float (__sincos, sincos)
108#endif
109