From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gateway24.websitewelcome.com (gateway24.websitewelcome.com [192.185.50.71]) by sourceware.org (Postfix) with ESMTPS id 97AFB3857C53 for ; Mon, 10 Aug 2020 19:15:29 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 97AFB3857C53 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=tromey.com Authentication-Results: sourceware.org; spf=fail smtp.mailfrom=tom@tromey.com Received: from cm12.websitewelcome.com (cm12.websitewelcome.com [100.42.49.8]) by gateway24.websitewelcome.com (Postfix) with ESMTP id 47868E6A3 for ; Mon, 10 Aug 2020 14:15:28 -0500 (CDT) Received: from box5379.bluehost.com ([162.241.216.53]) by cmsmtp with SMTP id 5DGak3C6Qn9FW5DGakm22G; Mon, 10 Aug 2020 14:15:28 -0500 X-Authority-Reason: nr=8 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=tromey.com; s=default; h=Content-Type:MIME-Version:Message-ID:In-Reply-To:Date: References:Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=3bVGQPc1u0Zdb+Oe+S89G5no4hZGCvBsUAevx5jo8k0=; b=Np1ysgXwPm0RvtDk6D1DN4Jxcn tIeRMSRTk4BpXBsXD9b+nL3MGu3uqkn7STrvJNvoRXpyLo6Vy5jFtix98tKT2bCxW4vkhAHdnK3I8 rCstHJV94CWoQD6luL4XFmdr9; Received: from 75-166-101-103.hlrn.qwest.net ([75.166.101.103]:45386 helo=murgatroyd) by box5379.bluehost.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1k5DGZ-002p4s-Sm; Mon, 10 Aug 2020 13:15:27 -0600 From: Tom Tromey To: Simon Marchi via Gdb-patches Cc: Simon Marchi , Morichetti@sourceware.org, Laurent Subject: Re: [PATCH 4/4] gdb: change regcache list to be a map References: <20200720204101.2849535-1-simon.marchi@efficios.com> <20200720204101.2849535-5-simon.marchi@efficios.com> X-Attribution: Tom Date: Mon, 10 Aug 2020 13:15:26 -0600 In-Reply-To: <20200720204101.2849535-5-simon.marchi@efficios.com> (Simon Marchi via Gdb-patches's message of "Mon, 20 Jul 2020 16:41:01 -0400") Message-ID: <87o8nijos1.fsf@tromey.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - box5379.bluehost.com X-AntiAbuse: Original Domain - sourceware.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - tromey.com X-BWhitelist: no X-Source-IP: 75.166.101.103 X-Source-L: No X-Exim-ID: 1k5DGZ-002p4s-Sm X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 75-166-101-103.hlrn.qwest.net (murgatroyd) [75.166.101.103]:45386 X-Source-Auth: tom+tromey.com X-Email-Count: 1 X-Source-Cap: ZWx5bnJvYmk7ZWx5bnJvYmk7Ym94NTM3OS5ibHVlaG9zdC5jb20= X-Local-Domain: yes X-Spam-Status: No, score=-3025.6 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, JMQ_SPF_NEUTRAL, RCVD_IN_ABUSEAT, RCVD_IN_BL_SPAMCOP_NET, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_PASS, SPF_NEUTRAL, TXREP autolearn=no autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 Aug 2020 19:15:31 -0000 >>>>> "Simon" == Simon Marchi via Gdb-patches writes: A bit late on this thread, but OTOH nothing too urgent to say... Simon> Note: In hash_target_ptid, I am combining hash values from std::hash by Simon> summing them. I don't think it's ideal, since std::hash is just the Simon> identity function for base types. But I don't know what would be better Simon> to reduce the change of collisions. If anybody has a better idea, I'd Simon> be interested. You can use fast_hash iteratively. It may not matter though. Simon> +/* Hash function for target_ptid. */ Simon> + Simon> +struct hash_target_ptid Simon> +{ Simon> + size_t operator() (const target_ptid &val) const Simon> + { It seems to me that for types that have a single "natural" hash, or a useful "canonical" hash (i.e., a hash we'd be likely to want to use by default in the normal case), we could specialize std::hash. For example, this code could do that. Tom