From patchwork Fri Mar 1 14:54:13 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ulrich Drepper X-Patchwork-Id: 224383 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) by ozlabs.org (Postfix) with SMTP id 2773A2C0292 for ; Sat, 2 Mar 2013 01:54:53 +1100 (EST) Comment: DKIM? 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See http://antispam.yahoo.com/domainkeys DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=default; d=gcc.gnu.org; h=Received:Received:X-SWARE-Spam-Status:X-Spam-Check-By:Received:Received:X-Received:MIME-Version:Received:In-Reply-To:References:From:Date:Message-ID:Subject:To:Cc:Content-Type:Mailing-List:Precedence:List-Id:List-Unsubscribe:List-Archive:List-Post:List-Help:Sender:Delivered-To; b=HnvIf58/0xN78Mvhi89k/ViPP8ygTDl5yuz1DK/qS1gEcnUtpvFBfQo3c7Pzek z/WDD5fDKGGbv22pO5lOn6PFnAd2998cbVJkTB0VT+GUY7MP7Brk53N7MOGUInEq fxsQQVmLxuCaqTZRm9U0/00Rj/B73ZMM2IsZAXUSaCq6Y=; Received: (qmail 30967 invoked by alias); 1 Mar 2013 14:54:45 -0000 Received: (qmail 30950 invoked by uid 22791); 1 Mar 2013 14:54:44 -0000 X-SWARE-Spam-Status: No, hits=-5.2 required=5.0 tests=AWL, BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, KHOP_RCVD_TRUST, KHOP_THREADED, RCVD_IN_DNSWL_LOW, RCVD_IN_HOSTKARMA_YE, TW_CX X-Spam-Check-By: sourceware.org Received: from mail-bk0-f46.google.com (HELO mail-bk0-f46.google.com) (209.85.214.46) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 01 Mar 2013 14:54:35 +0000 Received: by mail-bk0-f46.google.com with SMTP id j5so1410118bkw.33 for ; Fri, 01 Mar 2013 06:54:33 -0800 (PST) X-Received: by 10.204.127.14 with SMTP id e14mr4049759bks.95.1362149673658; Fri, 01 Mar 2013 06:54:33 -0800 (PST) MIME-Version: 1.0 Received: by 10.204.153.193 with HTTP; Fri, 1 Mar 2013 06:54:13 -0800 (PST) In-Reply-To: <51306C23.3090509@redhat.com> References: <20130221093859.33b4d2fe@oakwood> <51306C23.3090509@redhat.com> From: Ulrich Drepper Date: Fri, 1 Mar 2013 09:54:13 -0500 Message-ID: Subject: Re: [PATCH] C++ math constants To: Florian Weimer Cc: Benjamin De Kosnik , =?UTF-8?Q?Daniel_Kr=C3=BCgler?= , "libstdc++@gcc.gnu.org" , GCC Patches Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Delivered-To: mailing list gcc-patches@gcc.gnu.org How about this patch then? As I said, I have code in need of constants lined up and Edward likely also wants to take advantage of them in some of his code. + template + constexpr _RealType __math_constants<_RealType>::__phi; + template + constexpr _RealType __math_constants<_RealType>::__root_2; + template + constexpr _RealType __math_constants<_RealType>::__root_3; + template + constexpr _RealType __math_constants<_RealType>::__root_5; + template + constexpr _RealType __math_constants<_RealType>::__root_7; + template + constexpr _RealType __math_constants<_RealType>::__one_div_root_2; + +_GLIBCXX_END_NAMESPACE_VERSION +} // namespace __gnu_cxx + +#endif // C++11 + +#endif // _EXT_CMATH Index: include/Makefile.am =================================================================== --- include/Makefile.am (revision 196362) +++ include/Makefile.am (working copy) @@ -499,6 +499,7 @@ ${ext_srcdir}/array_allocator.h \ ${ext_srcdir}/bitmap_allocator.h \ ${ext_srcdir}/cast.h \ + ${ext_srcdir}/cmath \ ${ext_srcdir}/codecvt_specializations.h \ ${ext_srcdir}/concurrence.h \ ${ext_srcdir}/debug_allocator.h \ --- /dev/null 2013-02-06 19:11:05.441448320 -0500 +++ include/ext/cmath 2013-03-01 09:28:36.448535383 -0500 @@ -0,0 +1,152 @@ +// Math extensions -*- C++ -*- + +// Copyright (C) 2013 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// Under Section 7 of GPL version 3, you are granted additional +// permissions described in the GCC Runtime Library Exception, version +// 3.1, as published by the Free Software Foundation. + +// You should have received a copy of the GNU General Public License and +// a copy of the GCC Runtime Library Exception along with this program; +// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +// . + +/** @file ext/cmath + * This file is a GNU extension to the Standard C++ Library. + */ + +#ifndef _EXT_CMATH +#define _EXT_CMATH 1 + +#pragma GCC system_header + +#if __cplusplus < 201103L +# include +#else + +#include +#include + +namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) +{ +_GLIBCXX_BEGIN_NAMESPACE_VERSION + + // A class for math constants. + template + struct __math_constants + { + static_assert(std::is_floating_point<_RealType>::value, + "template argument not a floating point type"); + + // Constant @f$ \pi @f$. + static constexpr _RealType __pi = 3.1415926535897932384626433832795029L; + // Constant @f$ \pi / 2 @f$. + static constexpr _RealType __pi_half = 1.5707963267948966192313216916397514L; + // Constant @f$ \pi / 3 @f$. + static constexpr _RealType __pi_third = 1.0471975511965977461542144610931676L; + // Constant @f$ \pi / 4 @f$. + static constexpr _RealType __pi_quarter = 0.7853981633974483096156608458198757L; + // Constant @f$ \sqrt(\pi / 2) @f$. + static constexpr _RealType __root_pi_div_2 = 1.2533141373155002512078826424055226L; + // Constant @f$ 1 / \pi @f$. + static constexpr _RealType __one_div_pi = 0.3183098861837906715377675267450287L; + // Constant @f$ 2 / \pi @f$. + static constexpr _RealType __two_div_pi = 0.6366197723675813430755350534900574L; + // Constant @f$ 2 / \sqrt(\pi) @f$. + static constexpr _RealType __two_div_root_pi = 1.1283791670955125738961589031215452L; + + // Constant Euler's number @f$ e @f$. + static constexpr _RealType __e = 2.7182818284590452353602874713526625L; + // Constant @f$ 1 / e @f$. + static constexpr _RealType __one_div_e = 0.36787944117144232159552377016146087L; + // Constant @f$ \log_2(e) @f$. + static constexpr _RealType __log2_e = 1.4426950408889634073599246810018921L; + // Constant @f$ \log_10(e) @f$. + static constexpr _RealType __log10_e = 0.4342944819032518276511289189166051L; + // Constant @f$ \ln(2) @f$. + static constexpr _RealType __ln_2 = 0.6931471805599453094172321214581766L; + // Constant @f$ \ln(3) @f$. + static constexpr _RealType __ln_3 = 1.0986122886681096913952452369225257L; + // Constant @f$ \ln(10) @f$. + static constexpr _RealType __ln_10 = 2.3025850929940456840179914546843642L; + + // Constant Euler-Mascheroni @f$ \gamma_E @f$. + static constexpr _RealType __gamma_e = 0.5772156649015328606065120900824024L; + // Constant Golden Ratio @f$ \phi @f$. + static constexpr _RealType __phi = 1.6180339887498948482045868343656381L; + + // Constant @f$ \sqrt(2) @f$. + static constexpr _RealType __root_2 = 1.4142135623730950488016887242096981L; + // Constant @f$ \sqrt(3) @f$. + static constexpr _RealType __root_3 = 1.7320508075688772935274463415058724L; + // Constant @f$ \sqrt(5) @f$. + static constexpr _RealType __root_5 = 2.2360679774997896964091736687312762L; + // Constant @f$ \sqrt(7) @f$. + static constexpr _RealType __root_7 = 2.6457513110645905905016157536392604L; + // Constant @f$ 1 / \sqrt(2) @f$. + static constexpr _RealType __one_div_root_2 = 0.7071067811865475244008443621048490L; + }; + + // And the template definitions for the constants. + template + constexpr _RealType __math_constants<_RealType>::__pi; + template + constexpr _RealType __math_constants<_RealType>::__pi_half; + template + constexpr _RealType __math_constants<_RealType>::__pi_third; + template + constexpr _RealType __math_constants<_RealType>::__pi_quarter; + template + constexpr _RealType __math_constants<_RealType>::__root_pi_div_2; + template + constexpr _RealType __math_constants<_RealType>::__one_div_pi; + template + constexpr _RealType __math_constants<_RealType>::__two_div_pi; + template + constexpr _RealType __math_constants<_RealType>::__two_div_root_pi; + template + constexpr _RealType __math_constants<_RealType>::__e; + template + constexpr _RealType __math_constants<_RealType>::__one_div_e; + template + constexpr _RealType __math_constants<_RealType>::__log2_e; + template + constexpr _RealType __math_constants<_RealType>::__log10_e; + template + constexpr _RealType __math_constants<_RealType>::__ln_2; + template + constexpr _RealType __math_constants<_RealType>::__ln_3; + template + constexpr _RealType __math_constants<_RealType>::__ln_10; + template + constexpr _RealType __math_constants<_RealType>::__gamma_e;