From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qv1-xf29.google.com (mail-qv1-xf29.google.com [IPv6:2607:f8b0:4864:20::f29]) by sourceware.org (Postfix) with ESMTPS id 2AA603858C54 for ; Thu, 11 May 2023 18:15:25 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 2AA603858C54 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-qv1-xf29.google.com with SMTP id 6a1803df08f44-621350926dfso30347856d6.0 for ; Thu, 11 May 2023 11:15:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1683828924; x=1686420924; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=IPkZQWRi56LWPMuMlcApRrJs9mUt2ICEW5AqzXzKi+k=; b=Ny3gIQtn+DAiAmZuDZtwLHu5H7VJEgA0KjIXieMBccT3BnzDqw9MSNB0anuRDQknyw g2tARxG8iOHnDqWcBYpI83uT+orVRWbPEI70Ywr3VG+SDyn58bXdoStZuP80oAnzv0V2 bkSc5Era97LJXu2n5HcgyeZ7CXHeGafZGR+pZ5K53xBTxUgFgiCuIg8y66vDlUzw5cTT Wp6h3vHDh7y+0hTuwGMQq7PIUhA23iBimmGvUulJPZST5H8Sd7G3K7YxQUaKUKv/VAzi HtKY3cKfBH6oacTlx9zBXfkfxCpQfjeYlm8AVuikvAkJx21dM9BdtFWVPgF0cZ0qJ/Hm jZDg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683828924; x=1686420924; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=IPkZQWRi56LWPMuMlcApRrJs9mUt2ICEW5AqzXzKi+k=; b=Gqys7dDOCI8HiPz5lFgH8qMWbD0Hh09VuPUYKIb4GnKnxIZd6+HGravsb0y0mw797l 3aL7CFsuSycwMnb0msT4VkFtB3WkDI51d0Htl65pF1inF2a3mAM7Dq2AEGzAY4QubfuZ e9vK92ik54Ko22vR9isYgBJht6WwQEIZ15XZ0MhFdzB5LFLH5Gqlm6ToyurdK4vvTgjU j7ZqDVlxY1CNpSAQSA1rk0l1lWWx16+DLsDrAEleCPQfrMbgGg+tB5X60ArwppluVsse QuqKyl3bP62gvGcoXdNEcJ/9hzqwVaKA4DMwa/KI7aphK1IJgdRhJgCshHhrYvZTYVGb RY2A== X-Gm-Message-State: AC+VfDw3YDa+kGekfboA9bFuMf2o+IrQF3wV2PxyxOVpQYRZFH0hYh54 zrqpcfkzEeOZwyACczgkoLQ= X-Google-Smtp-Source: ACHHUZ6wz6uKkjLuUd+FMHkAyiD6aYMxxoSjOLPK6ZH76Ini7m0u/xASL/P+7yYhFiGCVwsF1Hvx1g== X-Received: by 2002:a05:6214:ca7:b0:616:5f27:b96a with SMTP id s7-20020a0562140ca700b006165f27b96amr35028379qvs.27.1683828923816; Thu, 11 May 2023 11:15:23 -0700 (PDT) Received: from ?IPV6:2607:fb90:46e:fe5b:9e7a:a7d5:520e:1fc2? ([2607:fb90:46e:fe5b:9e7a:a7d5:520e:1fc2]) by smtp.gmail.com with ESMTPSA id b8-20020a0ccd08000000b005dd8b9345f6sm2389497qvm.142.2023.05.11.11.15.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 11 May 2023 11:15:23 -0700 (PDT) Message-ID: Date: Thu, 11 May 2023 12:15:20 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.9.1 Subject: Re: [committed] Convert xstormy16 to LRA Content-Language: en-US To: Paul Koning , Hans-Peter Nilsson Cc: Roger Sayle , gcc-patches@gcc.gnu.org, segher@kernel.crashing.org References: <009601d97c85$de708170$9b518450$@nextmovesoftware.com> <20230511150540.9606F20420@pchp3.se.axis.com> <367738E7-2E0E-4406-8BBC-6DC70EA491DD@comcast.net> From: Jeff Law In-Reply-To: <367738E7-2E0E-4406-8BBC-6DC70EA491DD@comcast.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-3.6 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,NICE_REPLY_A,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,TXREP,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On 5/11/23 10:55, Paul Koning wrote: > > >> On May 11, 2023, at 11:05 AM, Hans-Peter Nilsson via Gcc-patches wrote: >> >> ... >> Yes, very interesting. Thank you for sharing this. I've >> seen regressions with LRA for CRIS too, for >> "double-register-sized" types, which for CRIS, a 32-bit >> target, translates to 64-bit types (DFmode and DImode), and >> where LRA does a much worse job than reload; spills a lot >> more often to stack, even after trying every >> register-allocation-related hook I found (and also an LRA >> patch which helped only by a fraction, but regressed results >> on x86_64-linux, so let's quickly forget it again). > > That observation makes me a bit worried. While CRIS may not be a priority platform, that description makes it sound like a case that would be significant in any 32 bit platform, which would include priority ones like i386 and ARM. If I understood things correctly, it seems to impact more when the target exposes double-word patterns but doesn't actually have instructions for those operations. That's an implementation pattern we've largely been moving away from over the last decade or so. Jeff