Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755483Ab0ARVXN (ORCPT ); Mon, 18 Jan 2010 16:23:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754646Ab0ARVXM (ORCPT ); Mon, 18 Jan 2010 16:23:12 -0500 Received: from mx1.redhat.com ([209.132.183.28]:50245 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754645Ab0ARVXK (ORCPT ); Mon, 18 Jan 2010 16:23:10 -0500 Message-ID: <4B54D0B6.4030706@redhat.com> Date: Mon, 18 Jan 2010 16:20:54 -0500 From: Masami Hiramatsu User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.5) Gecko/20091209 Fedora/3.0-3.fc11 Thunderbird/3.0 MIME-Version: 1.0 To: Jim Keniston CC: Peter Zijlstra , Srikar Dronamraju , Ingo Molnar , Arnaldo Carvalho de Melo , Ananth N Mavinakayanahalli , utrace-devel , Frederic Weisbecker , Maneesh Soni , Mark Wielaard , LKML Subject: Re: [RFC] [PATCH 1/7] User Space Breakpoint Assistance Layer (UBP) References: <20100116184833.2s0zihwbggkgccsk@imap.linux.ibm.com> <4B548521.7000704@redhat.com> <1263842482.5059.9.camel@localhost.localdomain> In-Reply-To: <1263842482.5059.9.camel@localhost.localdomain> X-Enigmail-Version: 1.0 Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1748 Lines: 46 Jim Keniston wrote: > On Mon, 2010-01-18 at 10:58 -0500, Masami Hiramatsu wrote: >> Jim Keniston wrote: >>> Not really. For #3 (boosting), you need to know everything for #2, >>> plus be able to compute the length of each instruction -- which we can >>> now do for x86. To emulate an instruction (#4), you need to replicate >>> what it does, side-effects and all. The x86 instruction set seems to >>> be adding new floating-point instructions all the time, and I bet even >>> Masami doesn't know what they all do, but so far, they all seem to >>> adhere to the instruction-length rules encoded in Masami's instruction >>> decoder. >> >> Actually, current x86 decoder doesn't support FP(x87) instructions.(even >> it already supported AVX) But I think it's not so hard to add it. >> > > At one point I verified that it worked for all the x87 instructions in > libm: > https://www.redhat.com/archives/utrace-devel/2009-March/msg00031.html > I'm pretty sure I tested mmx instructions as well. But I guess this was > before you rearranged the opcode tables. > > Yeah, it wouldn't be hard to add back in, at least for purposes of > computing instruction lengths. objdump -d /lib/libm.so.6 | awk -f arch/x86/tools/distill.awk | ./test_get_len Succeed: decoded and checked 37198 instructions Hmm, yeah, that's already supported :-D. Thank you, -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America), Inc. Software Solutions Division e-mail: mhiramat@redhat.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/