From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 72279 invoked by alias); 24 May 2017 07:53:39 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 71802 invoked by uid 89); 24 May 2017 07:53:17 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.6 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=ham version=3.3.2 spammy= X-HELO: mail-wm0-f51.google.com Received: from mail-wm0-f51.google.com (HELO mail-wm0-f51.google.com) (74.125.82.51) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 24 May 2017 07:53:14 +0000 Received: by mail-wm0-f51.google.com with SMTP id 7so53436650wmo.1 for ; Wed, 24 May 2017 00:53:17 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:mail-followup-to:cc:subject:references :date:in-reply-to:message-id:user-agent:mime-version; bh=Zm12ohDl/Yt0G/TriX9Ik9ebWULrX30qEHE1prjwDi0=; b=AnGND9jDl/mG/HzJoiz3hXEhMH5ikcguy2l1KKNKhCE7aO71DCmlUWSUiDCdpgor8n 5kPftL+/CQZi74fhlw3Pd0gQ9XG9GXxu9c5jEK4ZvIRUdpBkJfoKMYBQP8sBjrxaWRPr qcagbja35ToD8v6muCzPd1d8ecj1ljYgnM/+a9H1FOdczz28yqk0c9CAuEOS8sLYv3tA /EluJHHgHi7vLQJI31Muk0YdfS1zHEpNBFC1xwVap0K43m+dCMSsFA5N8RuQL6byieSw UfmoqeXA5BHDLqZ5ANo+cFN/9PNUz7wYLHCV6vlnWgq6aXQdb9UZhE5mKd2pIpATNoY9 ZMAw== X-Gm-Message-State: AODbwcB5nLBONu9VTRftpQGCFca46LVtxYqsCdyPK/+FXBaYdPeScXH5 F2jRIrrCBn/DAv1r X-Received: by 10.28.109.29 with SMTP id i29mr4751866wmc.113.1495612396237; Wed, 24 May 2017 00:53:16 -0700 (PDT) Received: from localhost (188.29.164.253.threembb.co.uk. [188.29.164.253]) by smtp.gmail.com with ESMTPSA id x9sm2604491wmb.21.2017.05.24.00.53.14 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 24 May 2017 00:53:15 -0700 (PDT) From: Richard Sandiford To: Robin Dapp Mail-Followup-To: Robin Dapp ,Richard Biener , GCC Patches , "Bin.Cheng" , Andreas Krebbel , richard.sandiford@linaro.org Cc: Richard Biener , GCC Patches , "Bin.Cheng" , Andreas Krebbel Subject: Re: [PATCH 2/5 v3] Vect peeling cost model References: <0296a54f-cb8d-d9b8-380a-9cc553dbb6da@linux.vnet.ibm.com> <2804E9EF-67D1-4EFD-AF29-65C634EBE24F@gmail.com> <6f1194a0-9e57-0028-faf4-6190beec2009@linux.vnet.ibm.com> <3e575f6d-874a-b260-1fc2-f4db1250c32b@linux.vnet.ibm.com> <15b3df5a-f6a1-23f0-57ff-1f065420df19@linux.vnet.ibm.com> <765ae66b-6294-6c39-a101-8c54a6be42ae@linux.vnet.ibm.com> <87mva3zaml.fsf@linaro.org> <5fe88af1-b9dc-ad8d-95e3-9843872f2e58@linux.vnet.ibm.com> Date: Wed, 24 May 2017 07:53:00 -0000 In-Reply-To: <5fe88af1-b9dc-ad8d-95e3-9843872f2e58@linux.vnet.ibm.com> (Robin Dapp's message of "Wed, 24 May 2017 09:21:47 +0200") Message-ID: <87inkqzo5y.fsf@linaro.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-SW-Source: 2017-05/txt/msg01829.txt.bz2 Robin Dapp writes: >> Not sure I've understood the series TBH, but is the npeel == vf / 2 >> there specifically for the "unknown number of peels" case? How do >> we distinguish that from the case in which the number of peels is >> known to be vf / 2 at compile time? Or have I missed the point >> completely? (probably yes, sorry!) > > Good point, that's not totally waterproof for future uses of > vect_get_peeling_costs_all_drs (). Currently, however, only when > peeling for unknown alignment vf != 0 will be passed to it (and vf == 0 > for the known alignment case), so we can distinguish the cases. Ah, makes sense now, thanks. Would you mind putting something like that last sentence in a comment? > In future, the whole vf/2 handling should be improved anyway since e.g. > it is hardcoded here as well as in tree-vect-loop.c. npeel = 0 also has > a double meaning, namely not peeling when peeling for known alignment > and peeling vf/2 iters when peeling for unknown alignment. Room for > improvement I guess :) Yeah :-) But thanks for the series, looks like a nice improvement. Richard