/* Implement __kernel_standard_l. Copyright (C) 2012-2016 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 <http://www.gnu.org/licenses/>. Parts based on k_standard.c from fdlibm: */ /* @(#)k_standard.c 5.1 93/09/24 */ /* * ==================================================== * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. * * Developed at SunPro, a Sun Microsystems, Inc. business. * Permission to use, copy, modify, and distribute this * software is freely granted, provided that this notice * is preserved. * ==================================================== */ #include <math.h> #include "math_private.h" #include <fenv.h> #include <float.h> #include <errno.h> static double zero = 0.0; /* Handle errors for a libm function as specified by TYPE (see comments in k_standard.c for details), with arguments X and Y, returning the appropriate return value for that function. */ long double __kernel_standard_l (long double x, long double y, int type) { double dx, dy; struct exception exc; fenv_t env; feholdexcept (&env); dx = x; dy = y; math_force_eval (dx); math_force_eval (dy); fesetenv (&env); switch (type) { case 221: /* powl (x, y) overflow. */ exc.arg1 = dx; exc.arg2 = dy; exc.type = OVERFLOW; exc.name = (char *) "powl"; if (_LIB_VERSION == _SVID_) { exc.retval = HUGE; y *= 0.5; if (x < zero && rint (y) != y) exc.retval = -HUGE; } else { exc.retval = HUGE_VAL; y *= 0.5; if (x < zero && rint (y) != y) exc.retval = -HUGE_VAL; } if (_LIB_VERSION == _POSIX_) __set_errno (ERANGE); else if (!matherr (&exc)) __set_errno (ERANGE); return exc.retval; case 222: /* powl (x, y) underflow. */ exc.arg1 = dx; exc.arg2 = dy; exc.type = UNDERFLOW; exc.name = (char *) "powl"; exc.retval = zero; y *= 0.5; if (x < zero && rint (y) != y) exc.retval = -zero; if (_LIB_VERSION == _POSIX_) __set_errno (ERANGE); else if (!matherr (&exc)) __set_errno (ERANGE); return exc.retval; default: return __kernel_standard (dx, dy, type); } }