mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-27 07:20:11 +00:00
155 lines
3.7 KiB
C
155 lines
3.7 KiB
C
/* Return value of complex exponential function for a float type.
|
|
Copyright (C) 1997-2017 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <complex.h>
|
|
#include <fenv.h>
|
|
#include <math.h>
|
|
#include <math_private.h>
|
|
#include <float.h>
|
|
|
|
CFLOAT
|
|
M_DECL_FUNC (__cexp) (CFLOAT x)
|
|
{
|
|
CFLOAT retval;
|
|
int rcls = fpclassify (__real__ x);
|
|
int icls = fpclassify (__imag__ x);
|
|
|
|
if (__glibc_likely (rcls >= FP_ZERO))
|
|
{
|
|
/* Real part is finite. */
|
|
if (__glibc_likely (icls >= FP_ZERO))
|
|
{
|
|
/* Imaginary part is finite. */
|
|
const int t = (int) ((M_MAX_EXP - 1) * M_MLIT (M_LN2));
|
|
FLOAT sinix, cosix;
|
|
|
|
if (__glibc_likely (M_FABS (__imag__ x) > M_MIN))
|
|
{
|
|
M_SINCOS (__imag__ x, &sinix, &cosix);
|
|
}
|
|
else
|
|
{
|
|
sinix = __imag__ x;
|
|
cosix = 1;
|
|
}
|
|
|
|
if (__real__ x > t)
|
|
{
|
|
FLOAT exp_t = M_EXP (t);
|
|
__real__ x -= t;
|
|
sinix *= exp_t;
|
|
cosix *= exp_t;
|
|
if (__real__ x > t)
|
|
{
|
|
__real__ x -= t;
|
|
sinix *= exp_t;
|
|
cosix *= exp_t;
|
|
}
|
|
}
|
|
if (__real__ x > t)
|
|
{
|
|
/* Overflow (original real part of x > 3t). */
|
|
__real__ retval = M_MAX * cosix;
|
|
__imag__ retval = M_MAX * sinix;
|
|
}
|
|
else
|
|
{
|
|
FLOAT exp_val = M_EXP (__real__ x);
|
|
__real__ retval = exp_val * cosix;
|
|
__imag__ retval = exp_val * sinix;
|
|
}
|
|
math_check_force_underflow_complex (retval);
|
|
}
|
|
else
|
|
{
|
|
/* If the imaginary part is +-inf or NaN and the real part
|
|
is not +-inf the result is NaN + iNaN. */
|
|
__real__ retval = M_NAN;
|
|
__imag__ retval = M_NAN;
|
|
|
|
feraiseexcept (FE_INVALID);
|
|
}
|
|
}
|
|
else if (__glibc_likely (rcls == FP_INFINITE))
|
|
{
|
|
/* Real part is infinite. */
|
|
if (__glibc_likely (icls >= FP_ZERO))
|
|
{
|
|
/* Imaginary part is finite. */
|
|
FLOAT value = signbit (__real__ x) ? 0 : M_HUGE_VAL;
|
|
|
|
if (icls == FP_ZERO)
|
|
{
|
|
/* Imaginary part is 0.0. */
|
|
__real__ retval = value;
|
|
__imag__ retval = __imag__ x;
|
|
}
|
|
else
|
|
{
|
|
FLOAT sinix, cosix;
|
|
|
|
if (__glibc_likely (M_FABS (__imag__ x) > M_MIN))
|
|
{
|
|
M_SINCOS (__imag__ x, &sinix, &cosix);
|
|
}
|
|
else
|
|
{
|
|
sinix = __imag__ x;
|
|
cosix = 1;
|
|
}
|
|
|
|
__real__ retval = M_COPYSIGN (value, cosix);
|
|
__imag__ retval = M_COPYSIGN (value, sinix);
|
|
}
|
|
}
|
|
else if (signbit (__real__ x) == 0)
|
|
{
|
|
__real__ retval = M_HUGE_VAL;
|
|
__imag__ retval = __imag__ x - __imag__ x;
|
|
}
|
|
else
|
|
{
|
|
__real__ retval = 0;
|
|
__imag__ retval = M_COPYSIGN (0, __imag__ x);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* If the real part is NaN the result is NaN + iNaN unless the
|
|
imaginary part is zero. */
|
|
__real__ retval = M_NAN;
|
|
if (icls == FP_ZERO)
|
|
__imag__ retval = __imag__ x;
|
|
else
|
|
{
|
|
__imag__ retval = M_NAN;
|
|
|
|
if (rcls != FP_NAN || icls != FP_NAN)
|
|
feraiseexcept (FE_INVALID);
|
|
}
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
declare_mgen_alias (__cexp, cexp)
|
|
|
|
#if M_LIBM_NEED_COMPAT (cexp)
|
|
declare_mgen_libm_compat (__cexp, cexp)
|
|
#endif
|