From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:55727) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Sn6wM-0000Q1-N3 for qemu-devel@nongnu.org; Fri, 06 Jul 2012 07:43:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Sn6wJ-0007Oq-H0 for qemu-devel@nongnu.org; Fri, 06 Jul 2012 07:43:14 -0400 Received: from mailout1.samsung.com ([203.254.224.24]:10784) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Sn6wJ-0007O8-6H for qemu-devel@nongnu.org; Fri, 06 Jul 2012 07:43:11 -0400 Received: from epcpsbgm2.samsung.com (mailout1.samsung.com [203.254.224.24]) by mailout1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0M6Q00EDDLUQ9NY0@mailout1.samsung.com> for qemu-devel@nongnu.org; Fri, 06 Jul 2012 20:43:05 +0900 (KST) Received: from [172.21.111.108] ([182.198.1.3]) by mmp1.samsung.com (Oracle Communications Messaging Server 7u4-24.01 (7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTPA id <0M6Q00MY1LVTB570@mmp1.samsung.com> for qemu-devel@nongnu.org; Fri, 06 Jul 2012 20:43:05 +0900 (KST) Date: Fri, 06 Jul 2012 20:43:06 +0900 From: Yeongkyoon Lee In-reply-to: Message-id: <4FF6CF4A.7070200@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=UTF-8; format=flowed Content-transfer-encoding: QUOTED-PRINTABLE References: <1341494619-4714-1-git-send-email-yeongkyoon.lee@samsung.com> <1341494619-4714-5-git-send-email-yeongkyoon.lee@samsung.com> Subject: Re: [Qemu-devel] [RFC][PATCH v2 4/4] configure: add CONFIG_QEMU_LDST_OPTIMIZATION for TCG qemu_ld/st optimization List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: laurent.desnogues@gmail.com, e.voevodin@samsung.com, qemu-devel@nongnu.org, chenwj@iis.sinica.edu.tw On 2012=EB=85=84 07=EC=9B=94 05=EC=9D=BC 23:06, Peter Maydell wrote: > On 5 July 2012 14:23, Yeongkyoon Lee w= rote: >> Add an option "--enable-ldst-optimization" to enable CONFIG_QEMU_L= DST_OPTIMIZATION macro for TCG qemu_ld/st optimization. It only works= with CONFIG_SOFTMMU and doesn't work with CONFIG_TCG_PASS_AREG0. > This shouldn't be a user settable config option -- we should > just identify what the optimal setting is for the guest/target > combination and use it. It looks better remove the option after it is confirmed that it works= =20 well for all the guest target architectures. >> case "$target_arch2" in >> alpha | sparc* | xtensa* | ppc*) >> echo "CONFIG_TCG_PASS_AREG0=3Dy" >> $config_target_mak >> + # qemu_ld/st optimization is not available with CONFIG_TCG_PA= SS_AREG0 >> + target_ldst_optimization=3D"no" > PASS_AREG0 is the way of the future -- you need to fix the ldst > optimization to work with it. There are two reasons to prevent working with PASS_AREG0. The first one is I'm not sure the history and future PASS_AREG0 and h= ave=20 not tested PASS_AREG0 which is only enabled for some guest architectu= res.. The second is a problem of too many conditional paths in sources. I think it is not late to combine the ldst optimization with PASS_ARE= G0=20 after the ldst optimization agreed as default.