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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 B5F27C3A5A6 for ; Sat, 31 Aug 2019 21:26:38 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 798FC22CE9 for ; Sat, 31 Aug 2019 21:26:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 798FC22CE9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=us.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:46436 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i4AtJ-0002R9-M2 for qemu-devel@archiver.kernel.org; Sat, 31 Aug 2019 17:26:37 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41004) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i4AsM-00021w-VR for qemu-devel@nongnu.org; Sat, 31 Aug 2019 17:25:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i4AsL-0003U4-TF for qemu-devel@nongnu.org; Sat, 31 Aug 2019 17:25:38 -0400 Received: from indium.canonical.com ([91.189.90.7]:44370) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1i4AsL-0003TE-OA for qemu-devel@nongnu.org; Sat, 31 Aug 2019 17:25:37 -0400 Received: from loganberry.canonical.com ([91.189.90.37]) by indium.canonical.com with esmtp (Exim 4.86_2 #2 (Debian)) id 1i4AsK-0005mW-Dq for ; Sat, 31 Aug 2019 21:25:36 +0000 Received: from loganberry.canonical.com (localhost [127.0.0.1]) by loganberry.canonical.com (Postfix) with ESMTP id 666002E80C8 for ; Sat, 31 Aug 2019 21:25:36 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Date: Sat, 31 Aug 2019 21:16:08 -0000 From: Paul Clarke To: qemu-devel@nongnu.org X-Launchpad-Notification-Type: bug X-Launchpad-Bug: product=qemu; status=New; importance=Undecided; assignee=None; X-Launchpad-Bug-Tags: ppc64 testcase X-Launchpad-Bug-Information-Type: Public X-Launchpad-Bug-Private: no X-Launchpad-Bug-Security-Vulnerability: no X-Launchpad-Bug-Commenters: 7-pc mark-cave-ayland philmd X-Launchpad-Bug-Reporter: Paul Clarke (7-pc) X-Launchpad-Bug-Modifier: Paul Clarke (7-pc) References: <156711057074.6835.13599471410604217618.malonedeb@soybean.canonical.com> Message-Id: <156728616849.28813.12077557970758555365.malone@chaenomeles.canonical.com> X-Launchpad-Message-Rationale: Subscriber (QEMU) @qemu-devel-ml X-Launchpad-Message-For: qemu-devel-ml Precedence: bulk X-Generated-By: Launchpad (canonical.com); Revision="19044"; Instance="production-secrets-lazr.conf" X-Launchpad-Hash: 9a72ab9dc470458dab075c8d09fe2a89331e2534 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 91.189.90.7 Subject: [Qemu-devel] [Bug 1841990] Re: instruction 'denbcdq' misbehaving X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Bug 1841990 <1841990@bugs.launchpad.net> Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" I have access to lots of Power hardware, and happy to test and help however I can! Thanks, Mark! -- = You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1841990 Title: instruction 'denbcdq' misbehaving Status in QEMU: New Bug description: Instruction 'denbcdq' appears to have no effect. Test case attached. On ppc64le native: -- gcc -g -O -mcpu=3Dpower9 bcdcfsq.c test-denbcdq.c -o test-denbcdq $ ./test-denbcdq 0x00000000000000000000000000000000 0x0000000000000000000000000000000c 0x22080000000000000000000000000000 $ ./test-denbcdq 1 0x00000000000000000000000000000001 0x0000000000000000000000000000001c 0x22080000000000000000000000000001 $ ./test-denbcdq $(seq 0 99) 0x00000000000000000000000000000064 0x0000000000000000000000000000100c 0x22080000000000000000000000000080 -- With "qemu-ppc64le -cpu power9" -- $ qemu-ppc64le -cpu power9 -L [...] ./test-denbcdq 0x00000000000000000000000000000000 0x0000000000000000000000000000000c 0x0000000000000000000000000000000c $ qemu-ppc64le -cpu power9 -L [...] ./test-denbcdq 1 0x00000000000000000000000000000001 0x0000000000000000000000000000001c 0x0000000000000000000000000000001c $ qemu-ppc64le -cpu power9 -L [...] ./test-denbcdq $(seq 100) 0x00000000000000000000000000000064 0x0000000000000000000000000000100c 0x0000000000000000000000000000100c -- I started looking at the code, but I got confused rather quickly. Could be related to endianness? I think denbcdq arrived on the scene before little-endian was a big deal. Maybe something to do with utilizing implicit floating-point register pairs... I don't think the right data is getting to helper_denbcdq, which would point back to the gen_fprp_ptr uses in dfp-impl.inc.c (GEN_DFP_T_FPR_I32_Rc). (Maybe?) To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1841990/+subscriptions