From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58393) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VuNEI-0005to-Mf for qemu-devel@nongnu.org; Sat, 21 Dec 2013 09:08:43 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VuNEA-0006BC-7H for qemu-devel@nongnu.org; Sat, 21 Dec 2013 09:08:34 -0500 Received: from mail-ea0-x234.google.com ([2a00:1450:4013:c01::234]:53221) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VuNE9-0006B0-WC for qemu-devel@nongnu.org; Sat, 21 Dec 2013 09:08:26 -0500 Received: by mail-ea0-f180.google.com with SMTP id f15so1530901eak.25 for ; Sat, 21 Dec 2013 06:08:24 -0800 (PST) Sender: Paolo Bonzini Message-ID: <52B5A0D5.4080005@redhat.com> Date: Sat, 21 Dec 2013 15:08:21 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <1387580412-5828-1-git-send-email-rth@twiddle.net> In-Reply-To: <1387580412-5828-1-git-send-email-rth@twiddle.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] tcg-i386: Use MOVBE if available List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Richard Henderson Cc: qemu-devel@nongnu.org Il 21/12/2013 00:00, Richard Henderson ha scritto: > + if (real_bswap && have_movbe) { > + tcg_out_modrm_offset(s, OPC_MOVBE_GyMy + P_DATA16 + seg, > + datalo, base, ofs); > + tcg_out_ext16u(s, datalo, datalo); Do partial register stalls still exist on Atom and Haswell? I don't remember exactly what you had to do to prevent them, but IIRC you first moved zero to the register and then overwrote the the low 16 bits. Paolo