From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from esa4.hgst.iphmx.com (esa4.hgst.iphmx.com [216.71.154.42]) by sourceware.org (Postfix) with ESMTPS id 0A6583858D34 for ; Wed, 17 Jun 2020 00:40:34 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 0A6583858D34 IronPort-SDR: zJqIB1PEqRltmFTJrsO3qGaxoxDn8ByiVwizLTNLnhV+0xOWNzYT2hizGT2/00QnYJ7rQ3MN0q kwjSkzHrswxWniqU07Xtc+pFSzly7PV0vGqxopZMxnQfjaAjjVvJjJSX9FzW+tPQ9aI48tQTMp i27vW//U0nA/duy3ScvQoQKu+k75GR3c2lxlvcMrqiBvoOGoWSRBfWQVrEfHtw0AjaJhppRLsa DdEm2vMErhHCtkCjEJZF263CXoxzBXepcZ8jWt6UWwp8bs38xUHhXHmC6/B5Ywac9jxhkt1aSV Uh4= X-IronPort-AV: E=Sophos;i="5.73,520,1583164800"; d="scan'208";a="140174310" Received: from h199-255-45-15.hgst.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 17 Jun 2020 08:40:34 +0800 IronPort-SDR: NtmHs4BZAyfVg3Z0dryy1fkwW5K2KKrbDYOKz7I+UX+7WLDUGkMad9qf+hKHRPa/xMzrf58tcd F9Q/jAExzwO3ApFH4aoSWkMU7cOdCLzJM= Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep02.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Jun 2020 17:29:16 -0700 IronPort-SDR: JgNaAD+227d0rJtIszRfRbwyTNAMScafGljij5t7aV8KU2Sp1ENuTMn6CPoiKwHsvxojqHYaWc C2sGOzJwIL0w== WDCIronportException: Internal Received: from unknown (HELO redsun52) ([10.149.66.28]) by uls-op-cesaip02.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Jun 2020 17:40:33 -0700 Date: Wed, 17 Jun 2020 01:40:28 +0100 (BST) From: "Maciej W. Rozycki" To: "Metzger, Markus T" cc: Simon Marchi , Shahab Vahedi , Luis Machado , "gdb@sourceware.org" , Shahab Vahedi Subject: RE: Why enforcing sw_breakpoint_from_kind() implementation in GDBserver targets In-Reply-To: Message-ID: References: <20200610174702.GA3486@gmail.com> <8f80e486-cca4-819b-7316-329832df985f@simark.ca> <20200611094048.GA1270@gmail.com> <07362b1e-3b9b-a858-ce7a-9a27daff511a@linaro.org> <20200611110053.GD1270@gmail.com> <335e5978-4893-b355-69cd-98a101f8dd2e@simark.ca> User-Agent: Alpine 2.21 (LFD 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Spam-Status: No, score=-5.8 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, 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@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 17 Jun 2020 00:40:36 -0000 On Mon, 15 Jun 2020, Metzger, Markus T via Gdb wrote: > > Note that this would only concern GDBserver, other server implementations > > of the remote protocol are free to support Z0 or not. But we could decide > > that all GDBserver ports have to support it. > > The Intel Graphics architecture uses breakpoint bits inside instructions. There > is no single breakpoint opcode as there is INT3 on IA, for example. > > The breakpoint can be ignored one time, which allows stepping over breakpoints > without having to remove them. This obviously only works if the breakpoint bit > in the original instruction is set and the instruction is not replaced with a fixed > breakpoint pattern. Hmm, it seems to me like a use case for the breakpoint kind. Maciej