From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=40855 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OFApA-0007do-Fz for qemu-devel@nongnu.org; Thu, 20 May 2010 14:50:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OFAp8-0001hz-4C for qemu-devel@nongnu.org; Thu, 20 May 2010 14:50:28 -0400 Received: from hall.aurel32.net ([88.191.82.174]:41333) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OFAp7-0001hf-UZ for qemu-devel@nongnu.org; Thu, 20 May 2010 14:50:26 -0400 Date: Thu, 20 May 2010 20:50:24 +0200 From: Aurelien Jarno Subject: Re: [Qemu-devel] [PATCH 03/22] tcg-i386: Tidy ext8u and ext16u operations. Message-ID: <20100520185024.GF20912@hall.aurel32.net> References: <20100519064713.GC25432@ohm.aurel32.net> <4BF42E7F.60008@twiddle.net> <20100520133908.GC18828@hall.aurel32.net> <20100520140428.GA1950@volta.aurel32.net> <4BF549FB.7000208@twiddle.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <4BF549FB.7000208@twiddle.net> Sender: Aurelien Jarno List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Richard Henderson Cc: qemu-devel@nongnu.org On Thu, May 20, 2010 at 07:40:59AM -0700, Richard Henderson wrote: > On 05/20/2010 07:04 AM, Aurelien Jarno wrote: > >> Do you have tried to compare the generated code before and after your > >> patch? I expect a few cases where your patch has some drawbacks, so I > >> don't know if there is a net gain on the size of the translated code. > >> > > > > I have done a quick test on /bin/ls. > > | instr | size | > > +--------+--------+ > > before | 101305 | 344770 | > > after | 101258 | 344829 | > > > > In short a small gain in the number of instructions, and a small loss in > > the size of the translated code. > > That was pretty much the test I would have done. > > So where are we? Is the patch acceptable as-is, or should I be > re-writing it without the constraints change? > Given the tests do not show a real improvement and given that it complexify the code generation, I don't think we should have such a patch. Could you please rewrite it without the constraints change? -- Aurelien Jarno GPG: 1024D/F1BCDB73 aurelien@aurel32.net http://www.aurel32.net