s_sinl.c revision 331722 
1/*-
2 * Copyright (c) 2007 Steven G. Kargl
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice unmodified, this list of conditions, and the following
10 *    disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: stable/11/lib/msun/src/s_sinl.c 331722 2018-03-29 02:50:57Z eadler $");
29
30#include <float.h>
31#ifdef __i386__
32#include <ieeefp.h>
33#endif
34
35#include "math.h"
36#include "math_private.h"
37#if LDBL_MANT_DIG == 64
38#include "../ld80/e_rem_pio2l.h"
39#elif LDBL_MANT_DIG == 113
40#include "../ld128/e_rem_pio2l.h"
41#else
42#error "Unsupported long double format"
43#endif
44
45long double
46sinl(long double x)
47{
48	union IEEEl2bits z;
49	int e0, s;
50	long double y[2];
51	long double hi, lo;
52
53	z.e = x;
54	s = z.bits.sign;
55	z.bits.sign = 0;
56
57	/* If x = +-0 or x is a subnormal number, then sin(x) = x */
58	if (z.bits.exp == 0)
59		return (x);
60
61	/* If x = NaN or Inf, then sin(x) = NaN. */
62	if (z.bits.exp == 32767)
63		return ((x - x) / (x - x));
64
65	ENTERI();
66
67	/* Optimize the case where x is already within range. */
68	if (z.e < M_PI_4) {
69		hi = __kernel_sinl(z.e, 0, 0);
70		RETURNI(s ? -hi : hi);
71	}
72
73	e0 = __ieee754_rem_pio2l(x, y);
74	hi = y[0];
75	lo = y[1];
76
77	switch (e0 & 3) {
78	case 0:
79	    hi = __kernel_sinl(hi, lo, 1);
80	    break;
81	case 1:
82	    hi = __kernel_cosl(hi, lo);
83	    break;
84	case 2:
85	    hi = - __kernel_sinl(hi, lo, 1);
86	    break;
87	case 3:
88	    hi = - __kernel_cosl(hi, lo);
89	    break;
90	}
91
92	RETURNI(hi);
93}
94