1234567891011121314151617181920212223242526272829303132333435363738 |
- /* Copyright (C) 2011-2016 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/>. */
- #include <math.h>
- #include "math_private.h"
- /* wrapper exp2(x) */
- double
- exp2 (double x)
- {
- #if defined(__UCLIBC_HAS_FENV__)
- double z = pow(2.0, x);
- if (__builtin_expect (!isfinite (z) || z == 0, 0)
- && isfinite (x) && _LIB_VERSION != _IEEE_)
- /* exp2 overflow: 44, exp2 underflow: 45 */
- return __kernel_standard (x, x, 44 + !!signbit (x));
- return z;
- #else
- return pow(2.0, x);
- #endif
- }
- libm_hidden_def(exp2)
|