1 /* Return value of complex exponential function for double complex value.
2 Copyright (C) 1997-2012 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
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.
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.
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/>. */
23 #include <math_private.h>
27 __cexp (__complex__ double x)
29 __complex__ double retval;
30 int rcls = fpclassify (__real__ x);
31 int icls = fpclassify (__imag__ x);
33 if (__builtin_expect (rcls >= FP_ZERO, 1))
35 /* Real part is finite. */
36 if (__builtin_expect (icls >= FP_ZERO, 1))
38 /* Imaginary part is finite. */
39 const int t = (int) ((DBL_MAX_EXP - 1) * M_LN2);
42 __sincos (__imag__ x, &sinix, &cosix);
46 double exp_t = __ieee754_exp (t);
59 /* Overflow (original real part of x > 3t). */
60 __real__ retval = DBL_MAX * cosix;
61 __imag__ retval = DBL_MAX * sinix;
65 double exp_val = __ieee754_exp (__real__ x);
66 __real__ retval = exp_val * cosix;
67 __imag__ retval = exp_val * sinix;
72 /* If the imaginary part is +-inf or NaN and the real part
73 is not +-inf the result is NaN + iNaN. */
74 __real__ retval = __nan ("");
75 __imag__ retval = __nan ("");
77 feraiseexcept (FE_INVALID);
80 else if (__builtin_expect (rcls == FP_INFINITE, 1))
82 /* Real part is infinite. */
83 if (__builtin_expect (icls >= FP_ZERO, 1))
85 /* Imaginary part is finite. */
86 double value = signbit (__real__ x) ? 0.0 : HUGE_VAL;
90 /* Imaginary part is 0.0. */
91 __real__ retval = value;
92 __imag__ retval = __imag__ x;
98 __sincos (__imag__ x, &sinix, &cosix);
100 __real__ retval = __copysign (value, cosix);
101 __imag__ retval = __copysign (value, sinix);
104 else if (signbit (__real__ x) == 0)
106 __real__ retval = HUGE_VAL;
107 __imag__ retval = __nan ("");
109 if (icls == FP_INFINITE)
110 feraiseexcept (FE_INVALID);
114 __real__ retval = 0.0;
115 __imag__ retval = __copysign (0.0, __imag__ x);
120 /* If the real part is NaN the result is NaN + iNaN. */
121 __real__ retval = __nan ("");
122 __imag__ retval = __nan ("");
124 if (rcls != FP_NAN || icls != FP_NAN)
125 feraiseexcept (FE_INVALID);
130 weak_alias (__cexp, cexp)
131 #ifdef NO_LONG_DOUBLE
132 strong_alias (__cexp, __cexpl)
133 weak_alias (__cexp, cexpl)