From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oa1-x2a.google.com (mail-oa1-x2a.google.com [IPv6:2001:4860:4864:20::2a]) by sourceware.org (Postfix) with ESMTPS id E5C4C386D616 for ; Mon, 20 Nov 2023 02:51:05 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org E5C4C386D616 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=ventanamicro.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=ventanamicro.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org E5C4C386D616 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=2001:4860:4864:20::2a ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1700448668; cv=none; b=V5mvEwXddGvEzDx8KrvO1hJtclD1u7nqqmU08EyWjLIFrONDirawBE4kcrwn4xNe5V8sk6IvWBmBSgR/v4Nmt6g8O3Vn9vLXTSCi4gmaufVUrOv/XmbnssSC1KGP+9nlsipzoTpzAKneoxAEkMLzXrwGYgwmy84gBshKkj562fo= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1700448668; c=relaxed/simple; bh=Bts/0jKgwp+xEsYU/NEqPgjkYCjHDxbz7fw6T/x1+dg=; h=DKIM-Signature:Message-ID:Date:MIME-Version:Subject:To:From; b=ChcoOwXCknT7sMuOhRwIfRJpehE/hsB/XSpfhTsMkEMeRwpqZ7W7fzV7WO3fOzmemwN27AYxAStWl3ZCsuiRDTKLq8f7UvFr2S8zRQva9JpLH1aVkPKWgtipmYJ+iu3yoECBn/id5/zttQUx6fz1b27HcyF6gJ28ceHWDWChD00= ARC-Authentication-Results: i=1; server2.sourceware.org Received: by mail-oa1-x2a.google.com with SMTP id 586e51a60fabf-1efad296d42so2306630fac.2 for ; Sun, 19 Nov 2023 18:51:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ventanamicro.com; s=google; t=1700448664; x=1701053464; darn=gcc.gnu.org; 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=sH9dGwVAE4Qlt9MKlw4a627AJsCHiYJFAXNvcY6kSiU=; b=op1La5ze9gQM04owKlWCeg4o5lYrHQi+W+vTQ4TRUPykRoPhWg3gJpB4lRbHVVHnEU e/MBBeqnnjur1U8JADrQhUdfnt3kbjTIcZoRWKT16LMNvwaL5O6B1AU5nJ2MjImZCJk3 kPKGuoLGqObQMq5PqQktvVA9wpZBmODkKR8ZsBO/HVkWyTgqk4i0J+MCOV3RAnJZteQM 3Rn/rlhXZg9TuGLKblO4tXhYqmW5ZQGwJdtLLhgX0UjuUQBvfIAKgfnvpHWEQNzYo0KU spfGglWpf9rc4XbWOMNIJ/wo3BohKOdKJm/6Yqtzqk0z5x9CtnNXJGdPsAfTHAMYA7Ru XmlA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700448664; x=1701053464; 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=sH9dGwVAE4Qlt9MKlw4a627AJsCHiYJFAXNvcY6kSiU=; b=sNiZzfXybqnoIwiEG8tXHNxSS1Y9qNMiuhXQsS+yEwa7BUqet//7wbHU/GkLgHKvli kVGJg/TVPO4CCh/25NGy14int4ZOWXixvRfeLYb7VFef+hIF1q28wyx+Rj7cr0+hAvR+ 1m3upguwC/tQEo3UwfQCUuAtJcFitGZuO6x2wEAmKzWm4XuRzaV4FUoFDVvX8xJFEPD7 bKtXdDSN/NCOkvz11CuU+w/xLRXqTK7IhAetztahhRrjTeyhkiMO/mOu7ZbCBLzwbb2M +JljEou/sFmN5lujuLVYOBNaqN1x/NO5HeLvWeiusNu0pOdq8wgV1mMVyDneZ5i6YO9X r+AQ== X-Gm-Message-State: AOJu0YxtYh5gTacuUtLbSI50/Ztp5+819u2IqTyCkR4cBDnJa/OB5iPf BcFqzdcid5j6urYEfiFHo5byqw== X-Google-Smtp-Source: AGHT+IG6W9vcKFHb4DKPfVzw2dFi9uC6JASeoOvVKAgCj/2JqjSgzM7DRjiSw0iFG3h3DE+uBf8DSg== X-Received: by 2002:a05:6870:2308:b0:1ea:38:8e34 with SMTP id w8-20020a056870230800b001ea00388e34mr7737415oao.17.1700448664280; Sun, 19 Nov 2023 18:51:04 -0800 (PST) Received: from [172.31.0.109] ([136.36.130.248]) by smtp.gmail.com with ESMTPSA id ef53-20020a0568701ab500b001efb3910402sm1208760oab.0.2023.11.19.18.51.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 19 Nov 2023 18:51:04 -0800 (PST) Message-ID: <463a5426-ad0b-4b2f-b630-2b7e664c65bb@ventanamicro.com> Date: Sun, 19 Nov 2023 19:51:03 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFA] New pass for sign/zero extension elimination Content-Language: en-US To: Oleg Endo , "gcc-patches@gcc.gnu.org" Cc: Jivan Hakobyan References: <6d5f8ba7-0c60-4789-87ae-68617ce6ac2c@ventanamicro.com> <5b865c34a380c7d08514ce5da8956d798e3478a8.camel@t-online.de> From: Jeff Law In-Reply-To: <5b865c34a380c7d08514ce5da8956d798e3478a8.camel@t-online.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-4.9 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,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 11/19/23 18:22, Oleg Endo wrote: > > On Sun, 2023-11-19 at 17:47 -0700, Jeff Law wrote: >> This is work originally started by Joern @ Embecosm. >> >> There's been a long standing sense that we're generating too many >> sign/zero extensions on the RISC-V port. REE is useful, but it's really >> focused on a relatively narrow part of the extension problem. >> >> What Joern's patch does is introduce a new pass which tracks liveness of >> chunks of pseudo regs. Specifically it tracks bits 0..7, 8..15, 16..31 >> and 32..63. >> >> If it encounters a sign/zero extend that sets bits that are never read, >> then it replaces the sign/zero extension with a narrowing subreg. The >> narrowing subreg usually gets eliminated by subsequent passes (it's just >> a copy after all). >> > > Have you tried it on SH, too? (and if so any numbers?) Just bootstrap with C regression testing on sh4/sh4eb. No data on improvements. Jeff