From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ej1-x62a.google.com (mail-ej1-x62a.google.com [IPv6:2a00:1450:4864:20::62a]) by sourceware.org (Postfix) with ESMTPS id E185E385843E for ; Tue, 5 Sep 2023 08:45:05 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org E185E385843E 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-ej1-x62a.google.com with SMTP id a640c23a62f3a-9a65f9147ccso187601566b.1 for ; Tue, 05 Sep 2023 01:45:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1693903504; x=1694508304; darn=gcc.gnu.org; h=content-transfer-encoding:in-reply-to:from:references:to :content-language:subject:cc:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=MNcJov2yrgXi1tU9vpS/SbAt+x/RKK1E1pHuWOnSbyE=; b=beO/neyTk+CgusQQ7izSZQE5jxbvi7OPzAOsbCEgy+mT8hadJuVsAeVQUyNN9y1GYK /PQ++GEm37sR/ZQA41whVeveA2cxqajyki1cJsU8tXY+fTXVcS/jd+hvDp3VUOP+usk+ 9kvxVf+Wmj6TsBrxZmBe9B1oEIQJAYwgUupboVQ59ih8SdrmnjRSuHaSn9vZ6ep3t4a3 VXIGWi5vQG/qCRDlhe/tcZ2TIKOWGj5H5Dba8zKWwLbyL6hK1DeZbDML1GGYAbYVRWIA MNAwUWlN47t9RX0JocGtRb/RjV7TmNOC/szEBaS57K+ZOoDRdrZcxSNhoZijNesmoE/f js9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1693903504; x=1694508304; h=content-transfer-encoding:in-reply-to:from:references:to :content-language:subject:cc:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=MNcJov2yrgXi1tU9vpS/SbAt+x/RKK1E1pHuWOnSbyE=; b=Jwou+oyV+KLKLBoLXJMgWYz25pphZ/fNNYSJBBxZy23L3bagHcJVj2JaA8SeEXNreI rgYCaDGTWB0vMk26TUsKJn43HzdR2eaepNv3wvh2ky850SmCrA5AxiVJYra4cTVac07f gxYyrnbX1ecX5yMqf5oyrEON5CbfZPgCFK6Y4Dq9qed3llb7lfiu1/fF1theirdIl618 +AEgWBZLBVUzpwtRYq2ODFwgsmCqh04IC4G8sWNJ0SIXo5PUCT3n8eu2vCHUm1wqef2m xVtySGEv2OZ90/spTbJ6TEO37m3Oa0LVVK9KFQlJPOPx883vLV9fKJ3wg82+znHtC9sl 2JnQ== X-Gm-Message-State: AOJu0YxQ2+JHkWkw9JZhzQxz0PNoIubT/ajk9k+8dwkJg4pyQM6grTVt +O8zBypOU2hVqiHCFrrALDk= X-Google-Smtp-Source: AGHT+IHPj/mBXJeht61+llRmrKhsDEqM22lnVnbe529DxR5M7IDBlWujD2HAuJHmf9D7KjhDUaeV3g== X-Received: by 2002:a17:907:2c54:b0:9a1:fe9c:eee6 with SMTP id hf20-20020a1709072c5400b009a1fe9ceee6mr8544921ejc.43.1693903503515; Tue, 05 Sep 2023 01:45:03 -0700 (PDT) Received: from [192.168.1.23] (ip-046-005-130-086.um12.pools.vodafone-ip.de. [46.5.130.86]) by smtp.gmail.com with ESMTPSA id z17-20020a170906241100b0099bd7b26639sm7332537eja.6.2023.09.05.01.45.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 05 Sep 2023 01:45:03 -0700 (PDT) Message-ID: <5e4a58e3-df61-31af-18a2-052b1a9605a3@gmail.com> Date: Tue, 5 Sep 2023 10:45:02 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Cc: rdapp.gcc@gmail.com Subject: Re: [PATCH] fwprop: Allow UNARY_P and check register pressure. Content-Language: en-US To: Jeff Law , gcc-patches , richard.sandiford@arm.com References: <5a90c8a9-1570-5af4-bfdc-19d097bfee6e@gmail.com> <9acc1a24-5d01-40ad-b4b2-5948585d3e8c@gmail.com> <48bed106-190e-ab5f-4099-fdfd4f5a193f@gmail.com> <77daf152-e1fe-4980-8297-d37901d925e8@gmail.com> From: Robin Dapp In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-4.0 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 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: > I imagine doing it in reverse postorder would still make sense. > > But my point was that, for the current fwprop limitation of substituting > into exactly one use of a register, we can check whether that use is > the *only* use of register. > > I.e. if we substitute: > > A: (set (reg R1) (foo (reg R2))) > > into: > > B: (set ... (reg R1) ...) > > if R1 and R2 are likely to be in the same register class, and if B > is the only user of R2, then we don't need to calculate register > pressure. The change is either neutral (if R2 died in A) or an > improvement (if R2 doesn't die in A, and so R1 and R2 were previously > live at the same time). Ah, understood, thanks. Sure, that one I can include. Regards Robin