From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca (simark.ca [158.69.221.121]) by sourceware.org (Postfix) with ESMTPS id 6C19A3858D34 for ; Wed, 15 Jul 2020 02:55:34 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 6C19A3858D34 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=simark.ca Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=simark@simark.ca Received: from [10.0.0.11] (173-246-6-90.qc.cable.ebox.net [173.246.6.90]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by simark.ca (Postfix) with ESMTPSA id EB4B41E5F9; Tue, 14 Jul 2020 22:55:32 -0400 (EDT) Subject: Re: [PATCH v3 2/3] arc: Add hardware loop detection To: Shahab Vahedi , gdb-patches@sourceware.org Cc: Shahab Vahedi , Tom Tromey , Anton Kolesov , Francois Bedard References: <20200428160437.1585-1-shahab.vahedi@gmail.com> <20200713154527.13430-1-shahab.vahedi@gmail.com> <20200713154527.13430-3-shahab.vahedi@gmail.com> From: Simon Marchi Message-ID: <1b6491a1-2cf0-46ec-8435-97d500b6fb44@simark.ca> Date: Tue, 14 Jul 2020 22:55:31 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200713154527.13430-3-shahab.vahedi@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: fr Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-3.9 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, SPF_HELO_PASS, SPF_PASS, TXREP autolearn=ham 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: Wed, 15 Jul 2020 02:55:35 -0000 On 2020-07-13 11:45 a.m., Shahab Vahedi wrote: > From: Shahab Vahedi > > For ARC there are registers that are not part of a required set in XML > target descriptions by default, but are almost always present on ARC > targets and are universally exposed by the ptrace interface. Hardware > loop registers being one of them. > > LP_START and LP_END auxiliary registers are hardware loop start and end. > Formally, they are optional, but it is hard to find an ARC configuration > that doesn't have them. They are always present in processors that can > run GNU/Linux. GDB needs to know about those registers to implement > proper software single stepping, since they affect what instruction > will be next. > > This commit adds the code to check for the existance of "lp_start" and > "lp_end" in XML target descriptions. If they exist, then the function > reports that the target supports hardware loops. This looks good to me. Simon