mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-14 01:00:07 +00:00
581c785bf3
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
130 lines
3.3 KiB
C
130 lines
3.3 KiB
C
/* Complex hyperbolic tangent for float types.
|
|
Copyright (C) 1997-2022 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <complex.h>
|
|
#include <fenv.h>
|
|
#include <math.h>
|
|
#include <math_private.h>
|
|
#include <math-underflow.h>
|
|
#include <float.h>
|
|
|
|
CFLOAT
|
|
M_DECL_FUNC (__ctanh) (CFLOAT x)
|
|
{
|
|
CFLOAT res;
|
|
|
|
if (__glibc_unlikely (!isfinite (__real__ x) || !isfinite (__imag__ x)))
|
|
{
|
|
if (isinf (__real__ x))
|
|
{
|
|
__real__ res = M_COPYSIGN (1, __real__ x);
|
|
if (isfinite (__imag__ x) && M_FABS (__imag__ x) > 1)
|
|
{
|
|
FLOAT sinix, cosix;
|
|
M_SINCOS (__imag__ x, &sinix, &cosix);
|
|
__imag__ res = M_COPYSIGN (0, sinix * cosix);
|
|
}
|
|
else
|
|
__imag__ res = M_COPYSIGN (0, __imag__ x);
|
|
}
|
|
else if (__imag__ x == 0)
|
|
{
|
|
res = x;
|
|
}
|
|
else
|
|
{
|
|
if (__real__ x == 0)
|
|
__real__ res = __real__ x;
|
|
else
|
|
__real__ res = M_NAN;
|
|
__imag__ res = M_NAN;
|
|
|
|
if (isinf (__imag__ x))
|
|
feraiseexcept (FE_INVALID);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
FLOAT sinix, cosix;
|
|
FLOAT den;
|
|
const int t = (int) ((M_MAX_EXP - 1) * M_MLIT (M_LN2) / 2);
|
|
|
|
/* tanh(x+iy) = (sinh(2x) + i*sin(2y))/(cosh(2x) + cos(2y))
|
|
= (sinh(x)*cosh(x) + i*sin(y)*cos(y))/(sinh(x)^2 + cos(y)^2). */
|
|
|
|
if (__glibc_likely (M_FABS (__imag__ x) > M_MIN))
|
|
{
|
|
M_SINCOS (__imag__ x, &sinix, &cosix);
|
|
}
|
|
else
|
|
{
|
|
sinix = __imag__ x;
|
|
cosix = 1;
|
|
}
|
|
|
|
if (M_FABS (__real__ x) > t)
|
|
{
|
|
/* Avoid intermediate overflow when the imaginary part of
|
|
the result may be subnormal. Ignoring negligible terms,
|
|
the real part is +/- 1, the imaginary part is
|
|
sin(y)*cos(y)/sinh(x)^2 = 4*sin(y)*cos(y)/exp(2x). */
|
|
FLOAT exp_2t = M_EXP (2 * t);
|
|
|
|
__real__ res = M_COPYSIGN (1, __real__ x);
|
|
__imag__ res = 4 * sinix * cosix;
|
|
__real__ x = M_FABS (__real__ x);
|
|
__real__ x -= t;
|
|
__imag__ res /= exp_2t;
|
|
if (__real__ x > t)
|
|
{
|
|
/* Underflow (original real part of x has absolute value
|
|
> 2t). */
|
|
__imag__ res /= exp_2t;
|
|
}
|
|
else
|
|
__imag__ res /= M_EXP (2 * __real__ x);
|
|
}
|
|
else
|
|
{
|
|
FLOAT sinhrx, coshrx;
|
|
if (M_FABS (__real__ x) > M_MIN)
|
|
{
|
|
sinhrx = M_SINH (__real__ x);
|
|
coshrx = M_COSH (__real__ x);
|
|
}
|
|
else
|
|
{
|
|
sinhrx = __real__ x;
|
|
coshrx = 1;
|
|
}
|
|
|
|
if (M_FABS (sinhrx) > M_FABS (cosix) * M_EPSILON)
|
|
den = sinhrx * sinhrx + cosix * cosix;
|
|
else
|
|
den = cosix * cosix;
|
|
__real__ res = sinhrx * coshrx / den;
|
|
__imag__ res = sinix * cosix / den;
|
|
}
|
|
math_check_force_underflow_complex (res);
|
|
}
|
|
|
|
return res;
|
|
}
|
|
|
|
declare_mgen_alias (__ctanh, ctanh)
|