From owner-freebsd-numerics@FreeBSD.ORG Thu Oct 31 13:27:38 2013 Return-Path: Delivered-To: freebsd-numerics@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 9734C60F for ; Thu, 31 Oct 2013 13:27:38 +0000 (UTC) (envelope-from m.e.sanliturk@gmail.com) Received: from mail-ie0-x22a.google.com (mail-ie0-x22a.google.com [IPv6:2607:f8b0:4001:c03::22a]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 6BB9E2CB9 for ; Thu, 31 Oct 2013 13:27:35 +0000 (UTC) Received: by mail-ie0-f170.google.com with SMTP id at1so4998485iec.1 for ; Thu, 31 Oct 2013 06:27:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type; bh=/aBaVvKh7ZLpjcUPHB5w/9gvap4nopKUjxyYnvLIqC0=; b=nNvWKckWMcP3133rESwCNMqGJaF72LdDg70sRNSW6J35z91v1eyh5tdHtYzhXZBbYe IzDlsjhmSrarRA9e/a4HyHly5PvF7YMoR6LqEp9NX/dYgkiRYouapqgGlTlbq79mxixP tUp1t34tMZfL7EFi2Tx9L/tZ0ZFTmwXIktaMFXaaojB6x2d1gnX92tMj8EXuoiVqgxT+ rnVW/vXdcfZvU4J4UKioHj27Mz3ZiaIL72WreX673MlkgomsMWqnILUoU6Gz0uMWGsoL +PEMkU9iLEtRiM37PGEY5le07o31IaMRrPmUgOuys1K6pw/WkiEsFF+eVXE28P/hPDb+ QviA== MIME-Version: 1.0 X-Received: by 10.43.78.20 with SMTP id zk20mr1022628icb.61.1383226054884; Thu, 31 Oct 2013 06:27:34 -0700 (PDT) Received: by 10.64.12.140 with HTTP; Thu, 31 Oct 2013 06:27:34 -0700 (PDT) Date: Thu, 31 Oct 2013 09:27:34 -0400 Message-ID: Subject: Representation of 128 bit floating point numbers in FreeBSD amd64 and Clang From: Mehmet Erol Sanliturk To: freebsd-numerics@freebsd.org Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 X-BeenThere: freebsd-numerics@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Discussions of high quality implementation of libm functions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 31 Oct 2013 13:27:38 -0000 Dear All , There are three kind of floating point numbers beside single precision numbers : http://en.wikipedia.org/wiki/Double_precision ( 64 bits ) http://en.wikipedia.org/wiki/Extended_precision ( 80 bits ) http://en.wikipedia.org/wiki/Quadruple-precision_floating-point_format ( 128 bits ) In Fortran , it is possible to define the following : REAL ( KIND = 8 ) , DOUBLE PRECISION : 64 bits , REAL ( KIND = 10 ) : 80 bits , REAL ( KIND = 16 ) : 128 bits ( 34 digits ) . In FreeBSD amd64 and Clang , how can I represent 128 bits ( 34 digits ) variables ? The following are available : double : 17 digits long double : 21 digits Thank you very much . Mehmet Erol Sanliturk