diff options
| -rw-r--r-- | ChangeLog | 7 | ||||
| -rw-r--r-- | NEWS | 12 | ||||
| -rw-r--r-- | math/e_exp2l.c | 44 | ||||
| -rw-r--r-- | math/libm-test.inc | 15 |
4 files changed, 69 insertions, 9 deletions
@@ -1,5 +1,12 @@ 2012-03-22 Joseph Myers <joseph@codesourcery.com> + [BZ #13824] + * math/e_exp2l.c: Include <float.h>. + (__ieee754_exp2l): Handle overflow and underflow cases + separately. Only pass fractional part of argument to + __ieee754_expl. + * math/libm-test.inc (exp2_test): Add more tests. + * sysdeps/ieee754/ldbl-128/k_cosl.c (__kernel_cosl): Negate y if negating x to take absolute value. * sysdeps/ieee754/ldbl-128/k_sincosl.c (__kernel_sincosl): @@ -11,12 +11,12 @@ Version 2.16 174, 350, 411, 2541, 2547, 2548, 2551, 2552, 2553, 2554, 2562, 2563, 2565, 2566, 2576, 3335, 3976, 3992, 4026, 4108, 4596, 4822, 5077, 5461, 5805, - 5993, 6471, 6730, 6884, 6907, 6911, 9739, 9902, 10110, 10135, 10140, 10210, - 10545, 10716, 11174, 11322, 11365, 11451, 11494, 12047, 13058, 13525, - 13526, 13527, 13528, 13529, 13530, 13531, 13532, 13533, 13547, 13551, - 13552, 13553, 13555, 13559, 13566, 13583, 13618, 13637, 13656, 13658, - 13673, 13695, 13704, 13706, 13726, 13738, 13786, 13792, 13806, 13840, - 13841, 13844, 13846, 13851, 13852, 13854, 13871, 13883 + 5993, 6471, 6730, 6884, 6907, 6911, 9739, 9902, 10110, 10135, 10140, + 10210, 10545, 10716, 11174, 11322, 11365, 11451, 11494, 12047, 13058, + 13525, 13526, 13527, 13528, 13529, 13530, 13531, 13532, 13533, 13547, + 13551, 13552, 13553, 13555, 13559, 13566, 13583, 13618, 13637, 13656, + 13658, 13673, 13695, 13704, 13706, 13726, 13738, 13786, 13792, 13806, + 13824, 13840, 13841, 13844, 13846, 13851, 13852, 13854, 13871, 13883 * ISO C11 support: diff --git a/math/e_exp2l.c b/math/e_exp2l.c index e7e493933a..8904d3e4a0 100644 --- a/math/e_exp2l.c +++ b/math/e_exp2l.c @@ -1,11 +1,49 @@ +/* Compute 2^x. + Copyright (C) 2012 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/>. */ + #include <math.h> #include <math_private.h> +#include <float.h> long double __ieee754_exp2l (long double x) { - /* This is a very stupid and inprecise implementation. It'll get - replaced sometime (soon?). */ - return __ieee754_expl (M_LN2l * x); + if (__builtin_expect (isless (x, (long double) LDBL_MAX_EXP), 1)) + { + if (__builtin_expect (isgreaterequal (x, (long double) (LDBL_MIN_EXP + - LDBL_MANT_DIG + - 1)), 1)) + { + int intx = (int) x; + long double fractx = x - intx; + return __scalbnl (__ieee754_expl (M_LN2l * fractx), intx); + } + else + { + /* Underflow or exact zero. */ + if (__isinfl (x)) + return 0; + else + return LDBL_MIN * LDBL_MIN; + } + } + else + /* Infinity, NaN or overflow. */ + return LDBL_MAX * x; } strong_alias (__ieee754_exp2l, __exp2l_finite) diff --git a/math/libm-test.inc b/math/libm-test.inc index 05a000e0c1..fad767dd02 100644 --- a/math/libm-test.inc +++ b/math/libm-test.inc @@ -3127,6 +3127,21 @@ exp2_test (void) TEST_f_f (exp2, -1e6, 0); TEST_f_f (exp2, 0.75L, 1.68179283050742908606225095246642979L); + TEST_f_f (exp2, 100.5, 1.792728671193156477399422023278661496394e+30L); + TEST_f_f (exp2, 127, 0x1p127); + TEST_f_f (exp2, -149, 0x1p-149); + +#ifndef TEST_FLOAT + TEST_f_f (exp2, 1000.25, 1.274245659452564874772384918171765416737e+301L); + TEST_f_f (exp2, 1023, 0x1p1023); + TEST_f_f (exp2, -1074, 0x1p-1074); +#endif + +#if defined TEST_LDOUBLE && LDBL_MAX_EXP >= 16384 + TEST_f_f (exp2, 16383, 0x1p16383L); + TEST_f_f (exp2, -16400, 0x1p-16400L); +#endif + END (exp2); } |