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 3EF56C4332B for ; Tue, 29 Dec 2020 20:06:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EB2F8221F8 for ; Tue, 29 Dec 2020 20:06:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726330AbgL2UGb (ORCPT ); Tue, 29 Dec 2020 15:06:31 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53610 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726198AbgL2UGX (ORCPT ); Tue, 29 Dec 2020 15:06:23 -0500 Received: from mail-wr1-x432.google.com (mail-wr1-x432.google.com [IPv6:2a00:1450:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E86AC061798 for ; Tue, 29 Dec 2020 12:05:34 -0800 (PST) Received: by mail-wr1-x432.google.com with SMTP id q18so15655722wrn.1 for ; Tue, 29 Dec 2020 12:05:34 -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=XL0RdMhJCBZ0gxMDc9iKNk8Af4u8BEydSMvvnNYLvbo=; b=n1e2OIexEXXAsoq04mAIPFhiIhGVLQ9MFkA4YCkEp6uk29X85xHEb/F7UELDnlrDc0 Ow9eUuxKzucImD+dFVvkTvl+nmrNfSSFmjTQpqud5czIpZ6yjicWFAGGuj77cZxmPX26 RSCRmRefysS9lhmvDhb8tHXsFiNA7dOO1nWM0/l/Cwwddhs3t/S3ANSxw3GSnhXwvsNo JMHCgvz5PU5Zvb8C8YFdtooFRTipuGuSYwWApmn2yu/B3unkhDAXvcx2QpfRcGyrbLj1 OU1464ZppQyiNDXb8ajkUY4JGRKBSfxzZhrTr7mS9VvcKLSBxpOyMcBUbxP7CE8VwS0g JQ6g== 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=XL0RdMhJCBZ0gxMDc9iKNk8Af4u8BEydSMvvnNYLvbo=; b=eeowYa0YNVO6mA9JEeUnZNoPkAfCpjkD+SbxQu/TE5nYtTPoKzj8RSi6D5xD/0NIOo PuqM61rOb1tUx8LvTDM6bGY+mpY8x+GOnTs0+CigKX1gfQgcjaHBYIuT7MJDqelQ/th+ I4WJLhiFVqH6sxe4GdOxuPlmQ3JLfjcn1byDgML3A4rELlT5L8xcKAZjz1/TlN0mwYAu V03HV2wqZAGguGdh4JFYxs5OBTD000/epJG12EBAaKic1SYN+NWRP1sCKPCQ91N5RGdZ 8u2dtcD9Y8NxUNdd+31YV/Lz6Lnpij7hWnH9nfOXyJ7WrKK9nW1yqfwTn9MNkukuBU+o ZZiw== X-Gm-Message-State: AOAM531JPxqyW/hHOecBKIAAtx/ozJIA96KMyzuxsYXZYoEiNP8RLQ+s 23dTd3frbWrPYUlECZ8CQNkWzsrZypY= X-Google-Smtp-Source: ABdhPJwDvaraAy3FXLY7SZgksNg1ZunomljQEWwaNvSUYlHsLjeOcNfW5qpIS1Yg90eP6m/1YwCg8A== X-Received: by 2002:a05:6000:185:: with SMTP id p5mr56917833wrx.403.1609272332770; Tue, 29 Dec 2020 12:05:32 -0800 (PST) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id u3sm70755596wre.54.2020.12.29.12.05.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 29 Dec 2020 12:05:32 -0800 (PST) Message-Id: <7214fa73fdd13418744903f6c769fdb77c9512ce.1609272328.git.gitgitgadget@gmail.com> In-Reply-To: References: From: "Elijah Newren via GitGitGadget" Date: Tue, 29 Dec 2020 20:05:22 +0000 Subject: [PATCH v3 3/9] diffcore-rename: simplify limit check 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 , Taylor Blau , Christian Couder , Elijah Newren , Elijah Newren Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org From: Elijah Newren diffcore-rename had two different checks of the form if ((a < limit || b < limit) && a * b <= limit * limit) This can be simplified to if (st_mult(a, b) <= st_mult(limit, limit)) which makes it clearer how we are checking for overflow, and makes it much easier to parse given the drop from 8 to 4 variable appearances. Signed-off-by: Elijah Newren --- diffcore-rename.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/diffcore-rename.c b/diffcore-rename.c index 1d6675c040d..16553ab259f 100644 --- a/diffcore-rename.c +++ b/diffcore-rename.c @@ -447,12 +447,16 @@ static int too_many_rename_candidates(int num_destinations, int num_sources, * growing larger than a "rename_limit" square matrix, ie: * * num_destinations * num_sources > rename_limit * rename_limit + * + * We use st_mult() to check overflow conditions; in the + * exceptional circumstance that size_t isn't large enough to hold + * the multiplication, the system won't be able to allocate enough + * memory for the matrix anyway. */ if (rename_limit <= 0) rename_limit = 32767; - if ((num_destinations <= rename_limit || num_sources <= rename_limit) && - ((uint64_t)num_destinations * (uint64_t)num_sources - <= (uint64_t)rename_limit * (uint64_t)rename_limit)) + if (st_mult(num_destinations, num_sources) + <= st_mult(rename_limit, rename_limit)) return 0; options->needed_rename_limit = @@ -468,9 +472,8 @@ static int too_many_rename_candidates(int num_destinations, int num_sources, continue; limited_sources++; } - if ((num_destinations <= rename_limit || limited_sources <= rename_limit) && - ((uint64_t)num_destinations * (uint64_t)limited_sources - <= (uint64_t)rename_limit * (uint64_t)rename_limit)) + if (st_mult(num_destinations, limited_sources) + <= st_mult(rename_limit, rename_limit)) return 2; return 1; } -- gitgitgadget