From patchwork Fri Mar 29 13:35:28 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella X-Patchwork-Id: 32087 Received: (qmail 123737 invoked by alias); 29 Mar 2019 13:36:39 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 121569 invoked by uid 89); 29 Mar 2019 13:36:17 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-24.5 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_ASCII_DIVIDERS, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_PASS autolearn=ham version=3.3.1 spammy=1023 X-HELO: mail-ua1-f66.google.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:subject:date:message-id:in-reply-to:references; bh=lTMW3XGfyYZPu9k98JqFneBXmo5QMzBzwgQNH6SFJt0=; b=o+HBqyBVbDnHWjcutYoPqvMIEZzY0DGlyTqhVN0JiqvLyvL4y3vZpYWKDDxA7qOvHo cNcr7+YzPigDmcJP00YlyGrhWUx6CqEWCqQNcE2XNghKKAbdasFpDlxWDdIzzW34rs8v eOL/Y14Fr6fI7nZq/JMfK2qjguTdm3SyDyS5Cx7LosjNQ8Ogbl+lePu61ZUPkzfiBAFq 6NojuP67HmsL8mZwOGiVazVbSU0bO/TdFcKS10t4h7/517LHkQOu3LskSWQqa5U2Km/2 2YqUQ3wpXenXuh4bWpCRWPVa12H56bUmZEWNexAz29ZHNDJdWosOsiP4/t9fVRevXxqO nvOg== Return-Path: From: Adhemerval Zanella To: libc-alpha@sourceware.org Subject: [PATCH 27/28] math: Use wordsize-64 version for s_logb Date: Fri, 29 Mar 2019 10:35:28 -0300 Message-Id: <20190329133529.22523-28-adhemerval.zanella@linaro.org> In-Reply-To: <20190329133529.22523-1-adhemerval.zanella@linaro.org> References: <20190329133529.22523-1-adhemerval.zanella@linaro.org> - The resulting binary difference on 32 bits architecture is minimum. On i686-linux-gnu (with architecture optimization routine removed) there is no different using logb benchtests - It helps wordsize-64 architectures that use ldbl-opt. - It add some code simplification with reduction of duplicated implementations. Checked on powerpc-linux-gnu (built without --with-cpu, with --with-cpu=power4 and with --with-cpu=power5+ and --disable-multi-arch), powerpc64-linux-gnu (built without --with-cp and with --with-cpu=power5+ and --disable-multi-arch). * sysdeps/ieee754/dbl-64/wordsize-64/s_logb.c: Move to ... * sysdeps/ieee754/dbl-64/s_logb.c: ... here. Add work around for powerpc32 integer 0 converting to -0. Reviewed-by: Gabriel F. T. Gomes --- sysdeps/ieee754/dbl-64/s_logb.c | 61 ++++++++++----------- sysdeps/ieee754/dbl-64/wordsize-64/s_logb.c | 47 ---------------- 2 files changed, 29 insertions(+), 79 deletions(-) delete mode 100644 sysdeps/ieee754/dbl-64/wordsize-64/s_logb.c diff --git a/sysdeps/ieee754/dbl-64/s_logb.c b/sysdeps/ieee754/dbl-64/s_logb.c index a6de1f6e49..e336251fda 100644 --- a/sysdeps/ieee754/dbl-64/s_logb.c +++ b/sysdeps/ieee754/dbl-64/s_logb.c @@ -1,22 +1,24 @@ -/* @(#)s_logb.c 5.1 93/09/24 */ -/* - * ==================================================== - * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. - * - * Developed at SunPro, a Sun Microsystems, Inc. business. - * Permission to use, copy, modify, and distribute this - * software is freely granted, provided that this notice - * is preserved. - * ==================================================== - */ +/* Compute radix independent exponent. + Copyright (C) 2011-2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper , 2011. -/* - * double logb(x) - * IEEE 754 logb. Included to pass IEEE test suite. Not recommend. - * Use ilogb instead. - */ + 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 + . */ #include + #include #include #include @@ -24,28 +26,23 @@ double __logb (double x) { - int32_t lx, ix, rix; + int64_t ix, ex; - EXTRACT_WORDS (ix, lx, x); - ix &= 0x7fffffff; /* high |x| */ - if ((ix | lx) == 0) + EXTRACT_WORDS64 (ix, x); + ix &= UINT64_C(0x7fffffffffffffff); + if (ix == 0) return -1.0 / fabs (x); - if (ix >= 0x7ff00000) + ex = ix >> 52; + if (ex == 0x7ff) return x * x; - if (__glibc_unlikely ((rix = ix >> 20) == 0)) + if (__glibc_unlikely (ex == 0)) { - /* POSIX specifies that denormal number is treated as - though it were normalized. */ - int ma; - if (ix == 0) - ma = __builtin_clz (lx) + 32; - else - ma = __builtin_clz (ix); - rix -= ma - 12; + int m = __builtin_clzll (ix); + ex -= m - 12; } - if (FIX_INT_FP_CONVERT_ZERO && rix == 1023) + if (FIX_INT_FP_CONVERT_ZERO && ex == 1023) return 0.0; - return (double) (rix - 1023); + return (double) (ex - 1023); } #ifndef __logb libm_alias_double (__logb, logb) diff --git a/sysdeps/ieee754/dbl-64/wordsize-64/s_logb.c b/sysdeps/ieee754/dbl-64/wordsize-64/s_logb.c deleted file mode 100644 index d9b40af2c7..0000000000 --- a/sysdeps/ieee754/dbl-64/wordsize-64/s_logb.c +++ /dev/null @@ -1,47 +0,0 @@ -/* Compute radix independent exponent. - Copyright (C) 2011-2019 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Ulrich Drepper , 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 - . */ - -#include - -#include -#include - - -double -__logb (double x) -{ - int64_t ix, ex; - - EXTRACT_WORDS64 (ix, x); - ix &= UINT64_C(0x7fffffffffffffff); - if (ix == 0) - return -1.0 / fabs (x); - ex = ix >> 52; - if (ex == 0x7ff) - return x * x; - if (__glibc_unlikely (ex == 0)) - { - int m = __builtin_clzll (ix); - ex -= m - 12; - } - return (double) (ex - 1023); -} -#ifndef __logb -libm_alias_double (__logb, logb) -#endif