glibc/math/w_atan2.c

46 lines
1.4 KiB
C

/* Copyright (C) 2011-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
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/>. */
/*
* wrapper atan2(y,x)
*/
#include <errno.h>
#include <math.h>
#include <math_private.h>
double
__atan2 (double y, double x)
{
double z;
if (__builtin_expect (x == 0.0 && y == 0.0, 0) && _LIB_VERSION == _SVID_)
return __kernel_standard (y, x, 3); /* atan2(+-0,+-0) */
z = __ieee754_atan2 (y, x);
if (__glibc_unlikely (z == 0.0 && y != 0.0 && __finite (x)))
__set_errno (ERANGE);
return z;
}
weak_alias (__atan2, atan2)
#ifdef NO_LONG_DOUBLE
strong_alias (__atan2, __atan2l)
weak_alias (__atan2, atan2l)
#endif