1/* Return value of complex exponential function for float complex value.
2 Copyright (C) 1997-2016 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 <complex.h>
21#include <fenv.h>
22#include <math.h>
23#include <math_private.h>
24#include <float.h>
25
26__complex__ float
27__cexpf (__complex__ float x)
28{
29 __complex__ float retval;
30 int rcls = fpclassify (__real__ x);
31 int icls = fpclassify (__imag__ x);
32
33 if (__glibc_likely (rcls >= FP_ZERO))
34 {
35 /* Real part is finite. */
36 if (__glibc_likely (icls >= FP_ZERO))
37 {
38 /* Imaginary part is finite. */
39 const int t = (int) ((FLT_MAX_EXP - 1) * M_LN2);
40 float sinix, cosix;
41
42 if (__glibc_likely (fabsf (__imag__ x) > FLT_MIN))
43 {
44 __sincosf (__imag__ x, &sinix, &cosix);
45 }
46 else
47 {
48 sinix = __imag__ x;
49 cosix = 1.0f;
50 }
51
52 if (__real__ x > t)
53 {
54 float exp_t = __ieee754_expf (t);
55 __real__ x -= t;
56 sinix *= exp_t;
57 cosix *= exp_t;
58 if (__real__ x > t)
59 {
60 __real__ x -= t;
61 sinix *= exp_t;
62 cosix *= exp_t;
63 }
64 }
65 if (__real__ x > t)
66 {
67 /* Overflow (original real part of x > 3t). */
68 __real__ retval = FLT_MAX * cosix;
69 __imag__ retval = FLT_MAX * sinix;
70 }
71 else
72 {
73 float exp_val = __ieee754_expf (__real__ x);
74 __real__ retval = exp_val * cosix;
75 __imag__ retval = exp_val * sinix;
76 }
77 math_check_force_underflow_complex (retval);
78 }
79 else
80 {
81 /* If the imaginary part is +-inf or NaN and the real part
82 is not +-inf the result is NaN + iNaN. */
83 __real__ retval = __nanf ("");
84 __imag__ retval = __nanf ("");
85
86 feraiseexcept (FE_INVALID);
87 }
88 }
89 else if (__glibc_likely (rcls == FP_INFINITE))
90 {
91 /* Real part is infinite. */
92 if (__glibc_likely (icls >= FP_ZERO))
93 {
94 /* Imaginary part is finite. */
95 float value = signbit (__real__ x) ? 0.0 : HUGE_VALF;
96
97 if (icls == FP_ZERO)
98 {
99 /* Imaginary part is 0.0. */
100 __real__ retval = value;
101 __imag__ retval = __imag__ x;
102 }
103 else
104 {
105 float sinix, cosix;
106
107 if (__glibc_likely (fabsf (__imag__ x) > FLT_MIN))
108 {
109 __sincosf (__imag__ x, &sinix, &cosix);
110 }
111 else
112 {
113 sinix = __imag__ x;
114 cosix = 1.0f;
115 }
116
117 __real__ retval = __copysignf (value, cosix);
118 __imag__ retval = __copysignf (value, sinix);
119 }
120 }
121 else if (signbit (__real__ x) == 0)
122 {
123 __real__ retval = HUGE_VALF;
124 __imag__ retval = __nanf ("");
125
126 if (icls == FP_INFINITE)
127 feraiseexcept (FE_INVALID);
128 }
129 else
130 {
131 __real__ retval = 0.0;
132 __imag__ retval = __copysignf (0.0, __imag__ x);
133 }
134 }
135 else
136 {
137 /* If the real part is NaN the result is NaN + iNaN unless the
138 imaginary part is zero. */
139 __real__ retval = __nanf ("");
140 if (icls == FP_ZERO)
141 __imag__ retval = __imag__ x;
142 else
143 {
144 __imag__ retval = __nanf ("");
145
146 if (rcls != FP_NAN || icls != FP_NAN)
147 feraiseexcept (FE_INVALID);
148 }
149 }
150
151 return retval;
152}
153#ifndef __cexpf
154weak_alias (__cexpf, cexpf)
155#endif
156