1/* Compute sine and cosine of argument.
2 Copyright (C) 1997-2020 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20#include <errno.h>
21#include <math.h>
22
23#include <math_private.h>
24#include <fenv_private.h>
25#include <math-underflow.h>
26#include <libm-alias-double.h>
27
28#define IN_SINCOS
29#include "s_sin.c"
30
31void
32__sincos (double x, double *sinx, double *cosx)
33{
34 mynumber u;
35 int k;
36
37 SET_RESTORE_ROUND_53BIT (FE_TONEAREST);
38
39 u.x = x;
40 k = u.i[HIGH_HALF] & 0x7fffffff;
41
42 if (k < 0x400368fd)
43 {
44 double a, da, y;
45 /* |x| < 2^-27 => cos (x) = 1, sin (x) = x. */
46 if (k < 0x3e400000)
47 {
48 if (k < 0x3e500000)
49 math_check_force_underflow (x);
50 *sinx = x;
51 *cosx = 1.0;
52 return;
53 }
54 /* |x| < 0.855469. */
55 else if (k < 0x3feb6000)
56 {
57 *sinx = do_sin (x, 0);
58 *cosx = do_cos (x, 0);
59 return;
60 }
61
62 /* |x| < 2.426265. */
63 y = hp0 - fabs (x);
64 a = y + hp1;
65 da = (y - a) + hp1;
66 *sinx = copysign (do_cos (a, da), x);
67 *cosx = do_sin (a, da);
68 return;
69 }
70 /* |x| < 2^1024. */
71 if (k < 0x7ff00000)
72 {
73 double a, da, xx;
74 unsigned int n;
75
76 /* If |x| < 105414350 use simple range reduction. */
77 n = k < 0x419921FB ? reduce_sincos (x, &a, &da) : __branred (x, &a, &da);
78 n = n & 3;
79
80 if (n == 1 || n == 2)
81 {
82 a = -a;
83 da = -da;
84 }
85
86 if (n & 1)
87 {
88 double *temp = cosx;
89 cosx = sinx;
90 sinx = temp;
91 }
92
93 *sinx = do_sin (a, da);
94 xx = do_cos (a, da);
95 *cosx = (n & 2) ? -xx : xx;
96 return;
97 }
98
99 if (isinf (x))
100 __set_errno (EDOM);
101
102 *sinx = *cosx = x / x;
103}
104libm_alias_double (__sincos, sincos)
105