From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 09802C2BBD4 for ; Wed, 16 Dec 2020 17:18:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E1B8F233EA for ; Wed, 16 Dec 2020 17:18:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727090AbgLPRSB (ORCPT ); Wed, 16 Dec 2020 12:18:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38094 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727087AbgLPRSA (ORCPT ); Wed, 16 Dec 2020 12:18:00 -0500 Received: from mail-wr1-x433.google.com (mail-wr1-x433.google.com [IPv6:2a00:1450:4864:20::433]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0F279C0617A7 for ; Wed, 16 Dec 2020 09:17:20 -0800 (PST) Received: by mail-wr1-x433.google.com with SMTP id c5so20283588wrp.6 for ; Wed, 16 Dec 2020 09:17:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=nn9UgILTGX/C+hxA4TygR14BXD/AKUWQcTklkASqVxE=; b=j9dz2CoPNHI/x9Ze2MsflfHPPk+CSZ6FEE1C4nzsB/Y+Zzt9HBITRxMBo3UdBq2xyB OzRgmvnT/b3Gi/vNO95uPibfDVBNbcPPTsSTzvsEfJdKWF/bzwSxSEGmsSV8NiLpiIdk UZJNDrEknaVz924tG3PbrnxwAqOb5ILrQx0UhU6ijeSZd4uvsAzFvYh5sUEPEMVTO3fO shR8lrrL1Jv+ZZIBF6iQA+Syk87hbD69iNwVjQnqhZevOw0G6cekZzTuuv3Ca5XrTMbw PxJlF0OnMnNR1/+H1WpSND9OglEAOk5IcpbnBlW+ieI3LmAlvjvsDAVxr/cKYtrRoKHc 3Z5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=nn9UgILTGX/C+hxA4TygR14BXD/AKUWQcTklkASqVxE=; b=Tgeaax3ovPkWF8Kk5OipxgOyNg4N/Npp2Z1GNfQtahtTQBga6/M4NKdvbKIxHbaAyV RdfHwLsk6c++XaeB5j2tNJkSyQTqUyDCRQVKg3j/3dd24VwvfJwFNF7/I6kIC/2jRnsn +zghv5ghgNIevF3TbzcUzb2kd+sPIcWOd2nG/LKkEqKMVF5gWM6fuL4K/V/tPNX2MnoT Xa6uRqrfEiqWV6YyoqEUdnl0rJkWzW2dkhjVqYw/ajpL3tfEno6/CEf5c2+25CLcq8gJ zquESglHx5xBx4XC5pLQdgcyLlXpflXUTu9ldUZ3wf3Dd+oTlv0eeMblMP/e3aBvVji/ zSFg== X-Gm-Message-State: AOAM530jeMYD+ErqPNZL0Nq38J9AIqQZHEbEl8mOYrybjMsdgn3yCXr0 0FeYVO3ueE8C+r2thvcRxe9sWUIYGo0= X-Google-Smtp-Source: ABdhPJzmlAj8ts6EWuyrYGnBH+aIBN9lOO3BSjlDBaN+f91esCduX1jiy0zpIJZ+bt5rmHZKfSowyw== X-Received: by 2002:adf:a3c1:: with SMTP id m1mr8288586wrb.28.1608139038582; Wed, 16 Dec 2020 09:17:18 -0800 (PST) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id n189sm3712221wmf.20.2020.12.16.09.17.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Dec 2020 09:17:18 -0800 (PST) Message-Id: <59216a155ae4f17b959b646e484dfe4a6038751d.1608139034.git.gitgitgadget@gmail.com> In-Reply-To: References: From: "Elijah Newren via GitGitGadget" Date: Wed, 16 Dec 2020 17:17:14 +0000 Subject: [PATCH v3 3/3] merge-ort: implement merge_incore_recursive() Fcc: Sent Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit MIME-Version: 1.0 To: git@vger.kernel.org Cc: Elijah Newren , Derrick Stolee , Johannes Schindelin , Elijah Newren , Elijah Newren Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Elijah Newren Implement merge_incore_recursive(), mostly through the use of a new helper function, merge_ort_internal(), which itself is based off merge_recursive_internal() from merge-recursive.c. This drops the number of failures in the testsuite when run under GIT_TEST_MERGE_ALGORITHM=ort from around 1500 to 647. Signed-off-by: Elijah Newren --- merge-ort.c | 108 ++++++++++++++++++++++++++++++++++++++++++++++++++-- merge-ort.h | 10 +++++ 2 files changed, 115 insertions(+), 3 deletions(-) diff --git a/merge-ort.c b/merge-ort.c index 7679c1d08e2..f01307f2ee0 100644 --- a/merge-ort.c +++ b/merge-ort.c @@ -1356,7 +1356,6 @@ static inline void set_commit_tree(struct commit *c, struct tree *t) c->maybe_tree = t; } -MAYBE_UNUSED static struct commit *make_virtual_commit(struct repository *repo, struct tree *tree, const char *comment) @@ -1369,7 +1368,6 @@ static struct commit *make_virtual_commit(struct repository *repo, return commit; } -MAYBE_UNUSED static struct commit_list *reverse_commit_list(struct commit_list *list) { struct commit_list *previous = NULL, *current, *backup; @@ -1478,6 +1476,91 @@ static void merge_ort_nonrecursive_internal(struct merge_options *opt, } } +/* + * Originally from merge_recursive_internal(); somewhat adapted, though. + */ +static void merge_ort_internal(struct merge_options *opt, + struct commit_list *merge_bases, + struct commit *h1, + struct commit *h2, + struct merge_result *result) +{ + struct commit_list *iter; + struct commit *merged_merge_bases; + const char *ancestor_name; + struct strbuf merge_base_abbrev = STRBUF_INIT; + + if (!merge_bases) { + merge_bases = get_merge_bases(h1, h2); + /* See merge-ort.h:merge_incore_recursive() declaration NOTE */ + merge_bases = reverse_commit_list(merge_bases); + } + + merged_merge_bases = pop_commit(&merge_bases); + if (merged_merge_bases == NULL) { + /* if there is no common ancestor, use an empty tree */ + struct tree *tree; + + tree = lookup_tree(opt->repo, opt->repo->hash_algo->empty_tree); + merged_merge_bases = make_virtual_commit(opt->repo, tree, + "ancestor"); + ancestor_name = "empty tree"; + } else if (opt->ancestor && !opt->priv->call_depth) { + ancestor_name = opt->ancestor; + } else if (merge_bases) { + ancestor_name = "merged common ancestors"; + } else { + strbuf_add_unique_abbrev(&merge_base_abbrev, + &merged_merge_bases->object.oid, + DEFAULT_ABBREV); + ancestor_name = merge_base_abbrev.buf; + } + + for (iter = merge_bases; iter; iter = iter->next) { + const char *saved_b1, *saved_b2; + struct commit *prev = merged_merge_bases; + + opt->priv->call_depth++; + /* + * When the merge fails, the result contains files + * with conflict markers. The cleanness flag is + * ignored (unless indicating an error), it was never + * actually used, as result of merge_trees has always + * overwritten it: the committed "conflicts" were + * already resolved. + */ + saved_b1 = opt->branch1; + saved_b2 = opt->branch2; + opt->branch1 = "Temporary merge branch 1"; + opt->branch2 = "Temporary merge branch 2"; + merge_ort_internal(opt, NULL, prev, iter->item, result); + if (result->clean < 0) + return; + opt->branch1 = saved_b1; + opt->branch2 = saved_b2; + opt->priv->call_depth--; + + merged_merge_bases = make_virtual_commit(opt->repo, + result->tree, + "merged tree"); + commit_list_insert(prev, &merged_merge_bases->parents); + commit_list_insert(iter->item, + &merged_merge_bases->parents->next); + + clear_or_reinit_internal_opts(opt->priv, 1); + } + + opt->ancestor = ancestor_name; + merge_ort_nonrecursive_internal(opt, + repo_get_commit_tree(opt->repo, + merged_merge_bases), + repo_get_commit_tree(opt->repo, h1), + repo_get_commit_tree(opt->repo, h2), + result); + strbuf_release(&merge_base_abbrev); + opt->ancestor = NULL; /* avoid accidental re-use of opt->ancestor */ +} + void merge_incore_nonrecursive(struct merge_options *opt, struct tree *merge_base, struct tree *side1, @@ -1495,5 +1578,24 @@ void merge_incore_recursive(struct merge_options *opt, struct commit *side2, struct merge_result *result) { - die("Not yet implemented"); + /* + * merge_incore_nonrecursive() exists for cases where we always + * know there is a well-defined single merge base. However, + * despite a similar structure, merge-recursive.c noted that some + * callers preferred to call the recursive logic anyway and still + * set a special name for opt->ancestor that would appear in + * merge.conflictStyle=diff3 output. + * + * git-am was one such example (it wanted to set opt->ancestor to + * "constructed merge base", since it created a fake merge base); + * it called the recursive merge logic through a special + * merge_recursive_generic() wrapper. + * + * Allow the same kind of special case here. + */ + int num_merge_bases_is_1 = (merge_bases && !merge_bases->next); + assert(opt->ancestor == NULL || num_merge_bases_is_1); + + merge_start(opt, result); + merge_ort_internal(opt, merge_bases, side1, side2, result); } diff --git a/merge-ort.h b/merge-ort.h index 55ae7ee865d..d53a0a339f3 100644 --- a/merge-ort.h +++ b/merge-ort.h @@ -34,6 +34,16 @@ struct merge_result { /* * rename-detecting three-way merge with recursive ancestor consolidation. * working tree and index are untouched. + * + * merge_bases will be consumed (emptied) so make a copy if you need it. + * + * NOTE: empirically, the recursive algorithm will perform better if you + * pass the merge_bases in the order of oldest commit to the + * newest[1][2]. + * + * [1] https://lore.kernel.org/git/nycvar.QRO.7.76.6.1907252055500.21907@tvgsbejvaqbjf.bet/ + * [2] commit 8918b0c9c2 ("merge-recur: try to merge older merge bases + * first", 2006-08-09) */ void merge_incore_recursive(struct merge_options *opt, struct commit_list *merge_bases, -- gitgitgadget