ipiq: Add simple IPI latency measure sysctls (2)
[dragonfly.git] / lib / libm / src / s_cosl.c
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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 *
6ff43c94 26 * $FreeBSD: head/lib/msun/src/s_cosl.c 240828 2012-09-22 15:38:29Z kargl $
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27 */
28
29/*
30 * Limited testing on pseudorandom numbers drawn within [-2e8:4e8] shows
31 * an accuracy of <= 0.7412 ULP.
32 */
33
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34#include <float.h>
35#ifdef __i386__
36#include <ieeefp.h>
37#endif
38
39#include "math.h"
1a3b704c 40#include "math_private.h"
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41#if LDBL_MANT_DIG == 64
42#include "../ld80/e_rem_pio2l.h"
43#elif LDBL_MANT_DIG == 113
44#include "../ld128/e_rem_pio2l.h"
45#else
46#error "Unsupported long double format"
47#endif
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48
49long double
50cosl(long double x)
51{
52 union IEEEl2bits z;
53 int e0;
54 long double y[2];
55 long double hi, lo;
56
57 z.e = x;
58 z.bits.sign = 0;
59
60 /* If x = +-0 or x is a subnormal number, then cos(x) = 1 */
61 if (z.bits.exp == 0)
62 return (1.0);
63
64 /* If x = NaN or Inf, then cos(x) = NaN. */
65 if (z.bits.exp == 32767)
66 return ((x - x) / (x - x));
67
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68 ENTERI();
69
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70 /* Optimize the case where x is already within range. */
71 if (z.e < M_PI_4)
6ff43c94 72 RETURNI(__kernel_cosl(z.e, 0));
1a3b704c 73
6ff43c94 74 e0 = __ieee754_rem_pio2l(x, y);
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75 hi = y[0];
76 lo = y[1];
77
78 switch (e0 & 3) {
79 case 0:
80 hi = __kernel_cosl(hi, lo);
81 break;
82 case 1:
83 hi = - __kernel_sinl(hi, lo, 1);
84 break;
85 case 2:
86 hi = - __kernel_cosl(hi, lo);
87 break;
88 case 3:
89 hi = __kernel_sinl(hi, lo, 1);
90 break;
91 }
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92
93 RETURNI(hi);
1a3b704c 94}