1 /* Complex cosine hyperbolic function for float types.
2 Copyright (C) 1997-2018 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 <http://www.gnu.org/licenses/>. */
19
20 #include "quadmath-imp.h"
21
22 __complex128
ccoshq(__complex128 x)23 ccoshq (__complex128 x)
24 {
25 __complex128 retval;
26 int rcls = fpclassifyq (__real__ x);
27 int icls = fpclassifyq (__imag__ x);
28
29 if (__glibc_likely (rcls >= QUADFP_ZERO))
30 {
31 /* Real part is finite. */
32 if (__glibc_likely (icls >= QUADFP_ZERO))
33 {
34 /* Imaginary part is finite. */
35 const int t = (int) ((FLT128_MAX_EXP - 1) * M_LN2q);
36 __float128 sinix, cosix;
37
38 if (__glibc_likely (fabsq (__imag__ x) > FLT128_MIN))
39 {
40 sincosq (__imag__ x, &sinix, &cosix);
41 }
42 else
43 {
44 sinix = __imag__ x;
45 cosix = 1;
46 }
47
48 if (fabsq (__real__ x) > t)
49 {
50 __float128 exp_t = expq (t);
51 __float128 rx = fabsq (__real__ x);
52 if (signbitq (__real__ x))
53 sinix = -sinix;
54 rx -= t;
55 sinix *= exp_t / 2;
56 cosix *= exp_t / 2;
57 if (rx > t)
58 {
59 rx -= t;
60 sinix *= exp_t;
61 cosix *= exp_t;
62 }
63 if (rx > t)
64 {
65 /* Overflow (original real part of x > 3t). */
66 __real__ retval = FLT128_MAX * cosix;
67 __imag__ retval = FLT128_MAX * sinix;
68 }
69 else
70 {
71 __float128 exp_val = expq (rx);
72 __real__ retval = exp_val * cosix;
73 __imag__ retval = exp_val * sinix;
74 }
75 }
76 else
77 {
78 __real__ retval = coshq (__real__ x) * cosix;
79 __imag__ retval = sinhq (__real__ x) * sinix;
80 }
81
82 math_check_force_underflow_complex (retval);
83 }
84 else
85 {
86 __imag__ retval = __real__ x == 0 ? 0 : nanq ("");
87 __real__ retval = __imag__ x - __imag__ x;
88 }
89 }
90 else if (rcls == QUADFP_INFINITE)
91 {
92 /* Real part is infinite. */
93 if (__glibc_likely (icls > QUADFP_ZERO))
94 {
95 /* Imaginary part is finite. */
96 __float128 sinix, cosix;
97
98 if (__glibc_likely (fabsq (__imag__ x) > FLT128_MIN))
99 {
100 sincosq (__imag__ x, &sinix, &cosix);
101 }
102 else
103 {
104 sinix = __imag__ x;
105 cosix = 1;
106 }
107
108 __real__ retval = copysignq (HUGE_VALQ, cosix);
109 __imag__ retval = (copysignq (HUGE_VALQ, sinix)
110 * copysignq (1, __real__ x));
111 }
112 else if (icls == QUADFP_ZERO)
113 {
114 /* Imaginary part is 0.0. */
115 __real__ retval = HUGE_VALQ;
116 __imag__ retval = __imag__ x * copysignq (1, __real__ x);
117 }
118 else
119 {
120 __real__ retval = HUGE_VALQ;
121 __imag__ retval = __imag__ x - __imag__ x;
122 }
123 }
124 else
125 {
126 __real__ retval = nanq ("");
127 __imag__ retval = __imag__ x == 0 ? __imag__ x : nanq ("");
128 }
129
130 return retval;
131 }
132