From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:38289) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UPTf5-0001Kq-IM for qemu-devel@nongnu.org; Tue, 09 Apr 2013 04:12:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UPTez-0005Y1-NE for qemu-devel@nongnu.org; Tue, 09 Apr 2013 04:12:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44809) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UPTez-0005Xv-Eq for qemu-devel@nongnu.org; Tue, 09 Apr 2013 04:12:09 -0400 Message-ID: <5163CD39.9000007@redhat.com> Date: Tue, 09 Apr 2013 10:11:37 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1365479139-18737-1-git-send-email-lig.fnst@cn.fujitsu.com> <20130409080529.GA86334@cs.nctu.edu.tw> In-Reply-To: <20130409080529.GA86334@cs.nctu.edu.tw> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH] translate: optimize gen_intermediate_code_internal List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?B?IumZs+mfi+S7uyAoV2VpLVJlbiBDaGVuKSI=?= Cc: peter.maydell@linaro.org, proljc@gmail.com, e.voevodin@samsung.com, qemu-devel@nongnu.org, blauwirbel@gmail.com, aurelien@aurel32.net, paul@codesourcery.com, afaerber@suse.de, liguang , rth@twiddle.net Il 09/04/2013 10:05, =E9=99=B3=E9=9F=8B=E4=BB=BB (Wei-Ren Chen) ha scritt= o: > Hi liguang, >=20 > Just to be curious, how much performance improvement this patch can g= et? I think zero. It is indeed making the code a tiny bit more readable in the 2nd/3rd/5th/6th hunks. But the 1st and 4th hunks, which do - num_insns =3D 0; are wrong. I'm surprised the compiler doesn't report usage of an uninitialized variable. liguang, how did you test them? Paolo > Regards, > chenwj