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author | Szabolcs Nagy <szabolcs.nagy@arm.com> | 2018-01-30 14:48:22 +0000 |
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committer | Szabolcs Nagy <szabolcs.nagy@arm.com> | 2018-02-12 11:33:33 +0000 |
commit | de800d83059dbedb7d151580f0a3bdc9eaf37340 (patch) | |
tree | 9c35197ab9d9788c73bd6aa5d7d19eb90979f629 /sysdeps/ieee754/dbl-64/slowexp.c | |
parent | c3d466cba1692708a19c6ff829d0386c83a0c6e5 (diff) | |
download | glibc-de800d83059dbedb7d151580f0a3bdc9eaf37340.tar glibc-de800d83059dbedb7d151580f0a3bdc9eaf37340.tar.gz glibc-de800d83059dbedb7d151580f0a3bdc9eaf37340.tar.bz2 glibc-de800d83059dbedb7d151580f0a3bdc9eaf37340.zip |
Remove slow paths from exp
Remove the __slowexp code, so exp is no longer correctly rounded. The
result is computed to about 70 bits precision so the worst case ulp
error is about 0.500007 in nearest rounding mode.
* manual/probes.texi: Remove slowexp probes.
* math/Makefile: Remove slowexp.
* sysdeps/generic/math_private.h (__slowexp): Remove.
* sysdeps/ieee754/dbl-64/e_exp.c (__ieee754_exp): Remove __slowexp and
document error bounds.
* sysdeps/i386/fpu/slowexp.c: Remove.
* sysdeps/ia64/fpu/slowexp.c: Remove.
* sysdeps/ieee754/dbl-64/slowexp.c: Remove.
* sysdeps/ieee754/dbl-64/uexp.h (err_0): Remove.
* sysdeps/m68k/m680x0/fpu/slowexp.c: Remove.
* sysdeps/powerpc/power4/fpu/Makefile (CPPFLAGS-slowexp.c): Remove.
* sysdeps/x86_64/fpu/multiarch/Makefile: Remove slowexp-fma.
* sysdeps/x86_64/fpu/multiarch/e_exp-avx.c (__slowexp): Remove.
* sysdeps/x86_64/fpu/multiarch/e_exp-fma.c (__slowexp): Remove.
* sysdeps/x86_64/fpu/multiarch/e_exp-fma4.c (__slowexp): Remove.
* sysdeps/x86_64/fpu/multiarch/slowexp-avx.c: Remove.
* sysdeps/x86_64/fpu/multiarch/slowexp-fma.c: Remove.
* sysdeps/x86_64/fpu/multiarch/slowexp-fma4.c: Remove.
Diffstat (limited to 'sysdeps/ieee754/dbl-64/slowexp.c')
-rw-r--r-- | sysdeps/ieee754/dbl-64/slowexp.c | 86 |
1 files changed, 0 insertions, 86 deletions
diff --git a/sysdeps/ieee754/dbl-64/slowexp.c b/sysdeps/ieee754/dbl-64/slowexp.c deleted file mode 100644 index ba5617466c..0000000000 --- a/sysdeps/ieee754/dbl-64/slowexp.c +++ /dev/null @@ -1,86 +0,0 @@ -/* - * IBM Accurate Mathematical Library - * written by International Business Machines Corp. - * Copyright (C) 2001-2018 Free Software Foundation, Inc. - * - * This program 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. - * - * This program 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 this program; if not, see <http://www.gnu.org/licenses/>. - */ -/**************************************************************************/ -/* MODULE_NAME:slowexp.c */ -/* */ -/* FUNCTION:slowexp */ -/* */ -/* FILES NEEDED:mpa.h */ -/* mpa.c mpexp.c */ -/* */ -/*Converting from double precision to Multi-precision and calculating */ -/* e^x */ -/**************************************************************************/ -#include <math_private.h> - -#include <stap-probe.h> - -#ifndef USE_LONG_DOUBLE_FOR_MP -# include "mpa.h" -void __mpexp (mp_no *x, mp_no *y, int p); -#endif - -#ifndef SECTION -# define SECTION -#endif - -/*Converting from double precision to Multi-precision and calculating e^x */ -double -SECTION -__slowexp (double x) -{ -#ifndef USE_LONG_DOUBLE_FOR_MP - double w, z, res, eps = 3.0e-26; - int p; - mp_no mpx, mpy, mpz, mpw, mpeps, mpcor; - - /* Use the multiple precision __MPEXP function to compute the exponential - First at 144 bits and if it is not accurate enough, at 768 bits. */ - p = 6; - __dbl_mp (x, &mpx, p); - __mpexp (&mpx, &mpy, p); - __dbl_mp (eps, &mpeps, p); - __mul (&mpeps, &mpy, &mpcor, p); - __add (&mpy, &mpcor, &mpw, p); - __sub (&mpy, &mpcor, &mpz, p); - __mp_dbl (&mpw, &w, p); - __mp_dbl (&mpz, &z, p); - if (w == z) - { - /* Track how often we get to the slow exp code plus - its input/output values. */ - LIBC_PROBE (slowexp_p6, 2, &x, &w); - return w; - } - else - { - p = 32; - __dbl_mp (x, &mpx, p); - __mpexp (&mpx, &mpy, p); - __mp_dbl (&mpy, &res, p); - - /* Track how often we get to the uber-slow exp code plus - its input/output values. */ - LIBC_PROBE (slowexp_p32, 2, &x, &res); - return res; - } -#else - return (double) __ieee754_expl((long double)x); -#endif -} |