diff options
Diffstat (limited to 'libm/w_powf.c')
-rw-r--r-- | libm/w_powf.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/libm/w_powf.c b/libm/w_powf.c new file mode 100644 index 000000000..fdfe82e8c --- /dev/null +++ b/libm/w_powf.c @@ -0,0 +1,76 @@ +/* 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 powf */ +float +powf (float x, float y) +{ +#if __UCLIBC_HAS_FENV__ + float z = (float) __ieee754_pow ((double) x, (double) y); + if (__builtin_expect (!isfinite (z), 0)) + { + if (_LIB_VERSION != _IEEE_) + { + if (isnan (x)) + { + if (y == 0.0f) + /* pow(NaN,0.0) */ + return __kernel_standard_f (x, y, 142); + } + else if (isfinite (x) && isfinite (y)) + { + if (isnan (z)) + /* pow neg**non-int */ + return __kernel_standard_f (x, y, 124); + else if (x == 0.0f && y < 0.0f) + { + if (signbit (x) && signbit (z)) + /* pow(-0.0,negative) */ + return __kernel_standard_f (x, y, 123); + else + /* pow(+0.0,negative) */ + return __kernel_standard_f (x, y, 143); + } + else + /* pow overflow */ + return __kernel_standard_f (x, y, 121); + } + } + } + else if (__builtin_expect (z == 0.0f, 0) && isfinite (x) && isfinite (y) + && _LIB_VERSION != _IEEE_) + { + if (x == 0.0f) + { + if (y == 0.0f) + /* pow(0.0,0.0) */ + return __kernel_standard_f (x, y, 120); + } + else + /* pow underflow */ + return __kernel_standard_f (x, y, 122); + } + + return z; +#else + return (float) __ieee754_pow ((double) x, (double) y); +#endif /* __UCLIBC_HAS_FENV__ */ +} |