From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id CC6E01F66F for ; Wed, 11 Nov 2020 17:13:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726920AbgKKRNO (ORCPT ); Wed, 11 Nov 2020 12:13:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59994 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726523AbgKKRNO (ORCPT ); Wed, 11 Nov 2020 12:13:14 -0500 Received: from mail-ot1-x344.google.com (mail-ot1-x344.google.com [IPv6:2607:f8b0:4864:20::344]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 24700C0613D1 for ; Wed, 11 Nov 2020 09:13:14 -0800 (PST) Received: by mail-ot1-x344.google.com with SMTP id y22so2801104oti.10 for ; Wed, 11 Nov 2020 09:13:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=6XMdWjtYWGkwzQGX8+rpnWb+J5jSmY2Mi1p9VmrP1EM=; b=rnRElACPyRd5C0fsIO7s1Trvs+W4+A+1dDazmevMUsiJzTIm1THUCpAVokVFnqiiV1 xxOqk8d0NXXEriehNvfx02ZKWYyCkVt1erAxjZwR/lmNnXS/nacOS1ccWkCJdPrigRG1 22HKT2JBZ1v+GYFT5qdyQUTexrkMh0Ei+QNOj98q4LbRZlqP6guWvJuANI4mYCU7ZgQi Lb5vWHfT/rkKlme/LVKEpTFXfpipXJpP+ocQgWxRdWL5on9MkfBiBCWZ6nKmDkUAmnRe po6QHtBiZ3htOUBzFl+18w0yzC7i7/jvSd71Sh9O3fFxzPwrdEIEx2Ji4kslZGH0nmTp G7bA== 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; bh=6XMdWjtYWGkwzQGX8+rpnWb+J5jSmY2Mi1p9VmrP1EM=; b=Nn1T3UUZZuEyrrDdVgSgZ4ozeH9bsEFonLmChQ8/Az0Ew389mPh/oXzzE5kB75MRBG QqFAoB0szEQWppPgRunIAowtGx1L4F8UoR9nVmASx1VGqeZtLzBCG3zp3fMZ09LgGh2v NCW9CvcMUBDMrZsjcetOSkC7w/yHlm8m41NinjmySe/dveZW5H/ZXXO7HftFqCNsiLUk 0ZOosyJZZSdajOgTpEqaE8GKICfOynal0BFul1cAErCTuwWvpw9hAMCciL4/6nkk7SuE bukYIMFom+qIljFkMY+rAlaxgmGq5hyjz6iAwf9V2NOl6OpaXQiqnKFnqgC3BBk7x300 oboQ== X-Gm-Message-State: AOAM532euX81Qptp1mYW3q01X+8inGTvJ/HLOdonJ294/g6PHaffQxPk mOcIeRHZMeqRfMdHDReeJMMF3Zqy/ba195KatdxazSADQOk= X-Google-Smtp-Source: ABdhPJyQeha1OEMbEDlAM8lYsStVKlWJJjw2mRk0F9Y025gWOqk1AImLUFYSUdDZoL29MbouFPSRVeRVH9cQiBBYFlg= X-Received: by 2002:a05:6830:1002:: with SMTP id a2mr19142784otp.316.1605114793525; Wed, 11 Nov 2020 09:13:13 -0800 (PST) MIME-Version: 1.0 References: <20201102204344.342633-1-newren@gmail.com> <20201102204344.342633-8-newren@gmail.com> In-Reply-To: From: Elijah Newren Date: Wed, 11 Nov 2020 09:13:02 -0800 Message-ID: Subject: Re: [PATCH v2 07/20] merge-ort: avoid repeating fill_tree_descriptor() on the same tree To: Derrick Stolee Cc: Git Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wed, Nov 11, 2020 at 6:51 AM Derrick Stolee wrote: > > On 11/2/2020 3:43 PM, Elijah Newren wrote: > > @@ -99,6 +99,15 @@ static int collect_merge_info_callback(int n, > > unsigned mbase_null = !(mask & 1); > > unsigned side1_null = !(mask & 2); > > unsigned side2_null = !(mask & 4); > > + unsigned side1_matches_mbase = (!side1_null && !mbase_null && > > + names[0].mode == names[1].mode && > > + oideq(&names[0].oid, &names[1].oid)); > > + unsigned side2_matches_mbase = (!side2_null && !mbase_null && > > + names[0].mode == names[2].mode && > > + oideq(&names[0].oid, &names[2].oid)); > > + unsigned sides_match = (!side1_null && !side2_null && > > + names[1].mode == names[2].mode && > > + oideq(&names[1].oid, &names[2].oid)); > > If the *_null values were in an array, instead, then all of these > lines could be grouped as a macro: > > unsigned null_oid[3] = { > !(mask & 1), > !(mask & 2), > !(mask & 4) > }; > > #define trivial_merge(i,j) (!null_oid[i] && !null_oid[j] && \ > names[i].mode == names[j].mode && \ > oideq(&names[i].oid, &names[j].oid)) > > unsigned side1_matches_mbase = trivial_merge(0, 1); > unsigned side2_matches_mbase = trivial_merge(0, 2); > unsigned sides_match = trivial_merge(1, 2); Hmm, I like it. I think I'll rename trivial_merge() to non_null_match() (trivial merge suggests it can immediately be resolved which is not necessarily true if rename detection is on), but otherwise I'll use this. > I briefly considered making these last three an array, as well, > except the loop below doesn't use 'i' in a symmetrical way: > > > + if (i == 1 && side1_matches_mbase) > > + t[1] = t[0]; > > + else if (i == 2 && side2_matches_mbase) > > + t[2] = t[0]; > > + else if (i == 2 && sides_match) > > + t[2] = t[1]; > > Since the 'i == 2' case has two possible options, it wouldn't be > possible to just have 'side_matches[i]' here. > > > + else { > > + const struct object_id *oid = NULL; > > + if (dirmask & 1) > > + oid = &names[i].oid; > > + buf[i] = fill_tree_descriptor(opt->repo, > > + t + i, oid); > > + } > > I do appreciate the reduced recursion here! Technically, not my own optimization; I just copied from unpack-trees.c:traverse_trees_recursive() -- though the code looks slightly different because I didn't want to compare oids multiple times (I use the side match variables earlier in the function as well).