From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=50878 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PEnvL-0002kP-CU for qemu-devel@nongnu.org; Sat, 06 Nov 2010 14:55:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PEnvK-00014q-AI for qemu-devel@nongnu.org; Sat, 06 Nov 2010 14:55:35 -0400 Received: from fe01x03-cgp.akado.ru ([77.232.31.164]:54227 helo=akado.ru) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PEnvJ-00014j-V6 for qemu-devel@nongnu.org; Sat, 06 Nov 2010 14:55:34 -0400 Date: Sat, 6 Nov 2010 21:55:26 +0300 (MSK) From: malc Subject: Re: [Qemu-devel] Bug report about x86 'bt' insn In-Reply-To: <86wroqmhso.fsf@shell.gmplib.org> Message-ID: References: <86eiay344b.fsf@shell.gmplib.org> <86wroqmhso.fsf@shell.gmplib.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Torbjorn Granlund Cc: qemu-devel@nongnu.org On Sat, 6 Nov 2010, Torbjorn Granlund wrote: > malc writes: > > ZF is undefined according to AMD's 24594.pdf page 69. > > Ah, you're right. It seems that all existing x86 implementations leave > ZF alone, though. (I am not arguing that qeum is broken, the bug is in > my code.) > > I apologize for the false alarm! Well, it's not as false as one would imagine, since QEMU sets lazy eflags evaluation function to SAR[BWL] in BT case which is not so good from performance standpoint. -- mailto:av1474@comtv.ru