From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ej1-x633.google.com (mail-ej1-x633.google.com [IPv6:2a00:1450:4864:20::633]) by sourceware.org (Postfix) with ESMTPS id 63B943857804 for ; Fri, 23 Apr 2021 01:46:23 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 63B943857804 Received: by mail-ej1-x633.google.com with SMTP id w3so71650549ejc.4 for ; Thu, 22 Apr 2021 18:46:23 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=tG/YgMZ4F9mkKerYDXc1o3ve8j719fdNyUNFOivqugs=; b=r6kQJ4ssWDTUnHcR0pwuQpwKdWcDt+29dDG7+ozBKEs+kIMzHIOQWYevKcKCIqplu2 OUGE5eTb1LffZLf529NO80WNHKkQBUsGU+cnkcZbCsKkacSryV7pJ8ZZ0AjJXQ/yF8ZR bnqRYzf8jL/4An5xHlt/fysEGrOLZ4YIKgjz/AGBBJowrEVSOEw3SX+zxFPvcqYxFOOT 6bg978qBZcckG6qOtFuyBdhmXBkzbQ60fW7uRfU029Tfn6+kQwUPwouitp7ExkkZxiZa VH+8kYlKDj7Lo/1k9zagXCMI3kl/kxDshlMeZvCU2oNUmWBEp9FtELTSZg8fH371/dCr 9Cew== X-Gm-Message-State: AOAM530M2w9VqlJItgIWUf8kItHVyHsFWc/CGxm6IQWq8ZGnycE9E5b5 w98eqDWHREbU9aoQlW5oQTr/g1ImtAAbJJ2kJgw= X-Google-Smtp-Source: ABdhPJxRQ2VR32Zws3cbU1UFxQ5VWnxTqiC5m4UjXVmc/nbObJZprRxz01fIo01hz55W2cLm9r/0Q8dhcuA6od+2nOI= X-Received: by 2002:a17:906:c01a:: with SMTP id e26mr1614654ejz.300.1619142381891; Thu, 22 Apr 2021 18:46:21 -0700 (PDT) MIME-Version: 1.0 References: <62330f82-201d-af7d-d1ed-1c8c529cc0f7@suse.cz> In-Reply-To: <62330f82-201d-af7d-d1ed-1c8c529cc0f7@suse.cz> From: "Bin.Cheng" Date: Fri, 23 Apr 2021 09:46:10 +0800 Message-ID: Subject: Re: State of AutoFDO in GCC To: =?UTF-8?Q?Martin_Li=C5=A1ka?= Cc: Eugene Rozenfeld , "gcc@gcc.gnu.org" , Jan Hubicka Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gcc@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Apr 2021 01:46:24 -0000 On Fri, Apr 23, 2021 at 4:16 AM Martin Li=C5=A1ka wrote: > > On 4/22/21 9:58 PM, Eugene Rozenfeld via Gcc wrote: > > GCC documentation for AutoFDO points to create_gcov tool that converts = perf.data file into gcov format that can be consumed by gcc with -fauto-pro= file (https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html, https://gcc= .gnu.org/wiki/AutoFDO/Tutorial). > > > > I noticed that the source code for create_gcov has been deleted from ht= tps://github.com/google/autofdo on April 7. I asked about that change in th= at repo and got the following reply: > > > > https://github.com/google/autofdo/pull/107#issuecomment-819108738 > > > > "Actually we didn't use create_gcov and havn't updated create_gcov for = years, and we also didn't have enough tests to guarantee it works (It was g= cc-4.8 when we used and verified create_gcov). If you need it, it is welcom= ed to update create_gcov and add it to the respository." > > > > Does this mean that AutoFDO is currently dead in gcc? > > Hello. > > Yes. I know that even basic test cases have been broken for years in the = GCC. > It's new to me that create_gcov was removed. > > I tend to send patch to GCC that will remove AutoFDO from GCC. > I known Bin spent some time working on AutoFDO, has he came up to somethi= ng? Hi Martin, I haven't touched this part for quite some time. I have no objection to removing it from GCC. However, I do have general concern that because of fewer users/developers, it's less likely and harder for new features to land in GCC. I have no idea if this is a real problem or how to fix it. OTOH, maybe removing rotten features, making GCC more(?) concise, and improving existing features that GCC is doing well is the right thing. Thanks, bin > > Martin > > > > > Thanks, > > > > Eugene > > >