gcc/libquadmath/math/casinhq.c

84 lines
2.4 KiB
C

/* Return arc hyperbole sine for __float128 value.
Copyright (C) 1997, 1998 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include "quadmath-imp.h"
__complex128
casinhq (__complex128 x)
{
__complex128 res;
int rcls = fpclassifyq (__real__ x);
int icls = fpclassifyq (__imag__ x);
if (rcls <= QUADFP_INFINITE || icls <= QUADFP_INFINITE)
{
if (icls == QUADFP_INFINITE)
{
__real__ res = copysignq (HUGE_VALQ, __real__ x);
if (rcls == QUADFP_NAN)
__imag__ res = nanq ("");
else
__imag__ res = copysignq (rcls >= QUADFP_ZERO ? M_PI_2q : M_PI_4q,
__imag__ x);
}
else if (rcls <= QUADFP_INFINITE)
{
__real__ res = __real__ x;
if ((rcls == QUADFP_INFINITE && icls >= QUADFP_ZERO)
|| (rcls == QUADFP_NAN && icls == QUADFP_ZERO))
__imag__ res = copysignq (0.0, __imag__ x);
else
__imag__ res = nanq ("");
}
else
{
__real__ res = nanq ("");
__imag__ res = nanq ("");
}
}
else if (rcls == QUADFP_ZERO && icls == QUADFP_ZERO)
{
res = x;
}
else
{
__complex128 y;
__real__ y = (__real__ x - __imag__ x) * (__real__ x + __imag__ x) + 1.0;
__imag__ y = 2.0 * __real__ x * __imag__ x;
y = csqrtq (y);
__real__ y += __real__ x;
__imag__ y += __imag__ x;
res = clogq (y);
/* Ensure zeros have correct sign and results are correct if
very close to branch cuts. */
__real__ res = copysignq (__real__ res, __real__ x);
__imag__ res = copysignq (__imag__ res, __imag__ x);
}
return res;
}