From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.0 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_EF,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id F043120248 for ; Wed, 3 Apr 2019 01:05:07 +0000 (UTC) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:subject:to:cc:references:from:message-id:date :mime-version:in-reply-to:content-type :content-transfer-encoding; q=dns; s=default; b=CB5nJayyYJn2ii7W 2uqV8J0WsVN88riDKv53oav3KRaKZISxTbj2hZlYAoJfK72m21RpbPpd8THlxafc 5uol0hwypotSzhY5gbRb7l1freaDIohlMPyUpoJJ3qHNlWhN2IjygycrWtEEKI6o kQJXPkwzu/IcuQYfY8WbVRqrelI= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:subject:to:cc:references:from:message-id:date :mime-version:in-reply-to:content-type :content-transfer-encoding; s=default; bh=D/pYl/GevHsKFCq9GOf2Fj k8ZiI=; b=N0yoOO3TijC8qZXXK1MJd1aDumHGzGcPDo0T85inicMTIvGva6e47U t9d7SnfQsNI3ZOXKZfYcrjR4Jt1NIGnQNr30ZKkaHRYNmIQEP1yKy3dE2jfUUJN2 DCeU05O+wlIY8kaIYBwyLKrdDTx3tpluAi1zGIyKS2kSg2GOncuaw= Received: (qmail 114415 invoked by alias); 3 Apr 2019 01:05:05 -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 Received: (qmail 114407 invoked by uid 89); 3 Apr 2019 01:05:05 -0000 Authentication-Results: sourceware.org; auth=none X-HELO: mail-pf1-f195.google.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=subject:to:cc:references:from:openpgp:autocrypt:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=dS5pmoAKOJtb4fuVWEJGoYrDpmqLSik0QHtQ+QoX/UQ=; b=P4bxmHSfYGGjFGMt02LrphEyuR6hamFbzTWLiCXv/pP9E5xxqt0O1knNwIkOGQMFnk scaToswaPZK0yNDzSU1LVP8c8Ms2ezaqtO2T6h6pu0wpIF39dW0tpExEjpS7yJhLWqkI zQF3n7f94vzGa7TBwGgq+GFLR82sIwNTMEmsAJQK9x3eGMceNVv3gU3L6rNJdtnKf5x5 kuzXNvHWyFIWJCgnuD/bTALd0mRNa9bivTa7FjvlBK/eaX2bBaJEQlWsWXe0b2IHQ8SW /gHKDFXmgaJogAAdWUTYnmtCh7Rhs8+9QHlSRQJ1KNrWx5l2rx8UGbdv6ac9GmhnZ1jO +bgg== Subject: Re: [PATCH 01/28] powerpc: Use generic fabs{f} implementations To: Joseph Myers Cc: libc-alpha@sourceware.org References: <20190329133529.22523-1-adhemerval.zanella@linaro.org> <20190329133529.22523-2-adhemerval.zanella@linaro.org> From: Adhemerval Zanella Openpgp: preference=signencrypt Message-ID: Date: Wed, 3 Apr 2019 08:04:57 +0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit On 02/04/2019 03:04, Joseph Myers wrote: > On Fri, 29 Mar 2019, Adhemerval Zanella wrote: > >> Since be2e25bbd78f9fdf the generic ieee754 implementation uses >> compiler builtin which generates fabs{f} for all supported targets. > > One reason for the existing version might be a microoptimization for code > size to make the float and double versions aliases, as permitted by the > ABIs and instruction set in this case. (This is not an objection to this > patch.) > Indeed powerpc does such microoptimizations for some implementations, but if the idea is indeed to push such optimizations couldn't add on generic implementation though a flag defined in arch-specific headers?