From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39860) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gL7EM-0000FF-2U for qemu-devel@nongnu.org; Fri, 09 Nov 2018 08:53:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gL7EG-0006je-Na for qemu-devel@nongnu.org; Fri, 09 Nov 2018 08:53:49 -0500 Received: from eddie.linux-mips.org ([148.251.95.138]:34238 helo=cvs.linux-mips.org) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gL7E9-0006LH-Ib for qemu-devel@nongnu.org; Fri, 09 Nov 2018 08:53:39 -0500 Received: (from localhost user: 'macro', uid#1010) by eddie.linux-mips.org with ESMTP id S23991062AbeKINx1h0uqw (ORCPT ); Fri, 9 Nov 2018 14:53:27 +0100 Date: Fri, 9 Nov 2018 13:53:27 +0000 (GMT) Sender: "Maciej W. Rozycki" From: "Maciej W. Rozycki" In-Reply-To: Message-ID: References: , , MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Subject: Re: [Qemu-devel] [PATCH v2 4/6] target/mips: Fix decoding mechanism of special R5900 opcodes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Aleksandar Markovic Cc: Fredrik Noring , Aurelien Jarno , =?UTF-8?Q?Philippe_Mathieu-Daud=C3=A9?= , =?UTF-8?Q?J=C3=BCrgen_Urban?= , "qemu-devel@nongnu.org" On Fri, 9 Nov 2018, Aleksandar Markovic wrote: > > ... and DMULT, DMULTU, DDIV and DDIVU > > are part of the MIPS III ISA. They are emulated in user mode to support > > generic MIPS III programs. > > Pure MIPS III executables should not be a concern of the R5900 > emulation, but R5900 executables. I repeat: MIPS III is the available instruction set defined with the base 64-bit MIPS Linux psABI and must not be subsetted. You have to support it in QEMU Linux user emulation mode for any 64-bit MIPS processor and this is not debatable, period. QEMU has no control over the Linux ABI, it has to accept it as it is. Maciej