From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id rpPvFy3amWTExw4AWB0awg (envelope-from ) for ; Mon, 26 Jun 2023 14:34:21 -0400 Authentication-Results: simark.ca; dkim=fail reason="signature verification failed" (768-bit key; unprotected) header.d=tromey.com header.i=@tromey.com header.a=rsa-sha256 header.s=default header.b=MT5Dn8sM; dkim-atps=neutral Received: by simark.ca (Postfix, from userid 112) id 53AE01E0BB; Mon, 26 Jun 2023 14:34:21 -0400 (EDT) Received: from sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPS id 335871E0AC for ; Mon, 26 Jun 2023 14:34:19 -0400 (EDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id A5E1A38582A1 for ; Mon, 26 Jun 2023 18:34:18 +0000 (GMT) Received: from gproxy3-pub.mail.unifiedlayer.com (gproxy3-pub.mail.unifiedlayer.com [69.89.30.42]) by sourceware.org (Postfix) with ESMTPS id 3FDF43858D1E for ; Mon, 26 Jun 2023 18:34:06 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 3FDF43858D1E Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=tromey.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=tromey.com Received: from cmgw13.mail.unifiedlayer.com (unknown [10.0.90.128]) by progateway5.mail.pro1.eigbox.com (Postfix) with ESMTP id CB018100406EF for ; Mon, 26 Jun 2023 18:34:03 +0000 (UTC) Received: from box5379.bluehost.com ([162.241.216.53]) by cmsmtp with ESMTP id Dr2JqTx6JNX2aDr2JqxQe4; Mon, 26 Jun 2023 18:34:03 +0000 X-Authority-Reason: nr=8 X-Authority-Analysis: v=2.4 cv=NMAQR22g c=1 sm=1 tr=0 ts=6499da1b a=ApxJNpeYhEAb1aAlGBBbmA==:117 a=ApxJNpeYhEAb1aAlGBBbmA==:17 a=dLZJa+xiwSxG16/P+YVxDGlgEgI=:19 a=of4jigFt-DYA:10:nop_rcvd_month_year a=Qbun_eYptAEA:10:endurance_base64_authed_username_1 a=CCpqsmhAAAAA:8 a=q60ehWb2FicBkGMxAzkA:9 a=ul9cdbp4aOFLsgKbc677:22 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=qQdfjdvpGa+9JlWB3HXRLXPG9QKBScNlNMI/ZP0BUwM=; b=MT5Dn8sMhzhYFVuWfUKnR2a8cl wDS4X5e9iSe1Dt27hoH/O0iMeEeTwEgOKPbfoOPYZxfXdZa2/zdio3E9Xv0Yfo0/dpuQBK/cxTISU 9GJlu9LaF0Wsjnd/9gHMf5WXM; Received: from 71-211-136-248.hlrn.qwest.net ([71.211.136.248]:39394 helo=murgatroyd) by box5379.bluehost.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1qDr2J-002vEM-BG; Mon, 26 Jun 2023 12:34:03 -0600 From: Tom Tromey To: Simon Farre via Gdb-patches Cc: Simon Farre Subject: Re: [PATCH v1] gdb/DAP Fix disassemble bug References: <20230626161654.207687-1-simon.farre.cx@gmail.com> X-Attribution: Tom Date: Mon, 26 Jun 2023 12:34:02 -0600 In-Reply-To: <20230626161654.207687-1-simon.farre.cx@gmail.com> (Simon Farre via Gdb-patches's message of "Mon, 26 Jun 2023 18:16:54 +0200") Message-ID: <87cz1ixecl.fsf@tromey.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (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: 71.211.136.248 X-Source-L: No X-Exim-ID: 1qDr2J-002vEM-BG X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 71-211-136-248.hlrn.qwest.net (murgatroyd) [71.211.136.248]:39394 X-Source-Auth: tom+tromey.com X-Email-Count: 1 X-Source-Cap: ZWx5bnJvYmk7ZWx5bnJvYmk7Ym94NTM3OS5ibHVlaG9zdC5jb20= X-Local-Domain: yes X-Spam-Status: No, score=-3018.7 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, JMQ_SPF_NEUTRAL, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) 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: , Errors-To: gdb-patches-bounces+public-inbox=simark.ca@sourceware.org Sender: "Gdb-patches" >>>>> "Simon" == Simon Farre via Gdb-patches writes: Simon> Fixes disassembleRequest Simon> The field instructionOffset can be negative. Previous patch made it so Simon> that sometimes the request got calculated to 0 instructions, when it Simon> meant to retrieve disasm for -50 to 0 (current position). I don't think this will work correctly, because this isn't counting by instruction but rather by byte. instructionOffset is defined in terms of instructions: Offset (in instructions) to be applied after the byte offset (if any) before disassembling. Can be negative. I must have missed the "negative" note, or maybe I just ignored it without documenting that -- since I wonder how it can possibly work. it seems to me that on architectures with variable length instructions, you can't really disassemble in "reverse" like that. I guess one idea would be to back up to the previous symbol and start disassembling from there. I feel like the TUI did this, though, and ran into all kinds of weird corner cases. Simon> - for elt in arch.disassemble(pc, count=total_count)[skip_insns:]: I notice now that the current code also neglects this part of the spec: * An adapter must return exactly this number of instructions - any * unavailable instructions should be replaced with an implementation-defined * 'invalid instruction' value. Tom