From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53326) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gWTUT-0003CU-Rr for qemu-devel@nongnu.org; Mon, 10 Dec 2018 16:53:26 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gWTUQ-0002Oz-JY for qemu-devel@nongnu.org; Mon, 10 Dec 2018 16:53:25 -0500 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:46525) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gWTUQ-0002N7-7y for qemu-devel@nongnu.org; Mon, 10 Dec 2018 16:53:22 -0500 Date: Mon, 10 Dec 2018 16:53:19 -0500 From: "Emilio G. Cota" Message-ID: <20181210215319.GA25006@flamenco> References: <20181203160840.15115-1-richard.henderson@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181203160840.15115-1-richard.henderson@linaro.org> Subject: Re: [Qemu-devel] [PATCH for-4.0 0/5] tcg/i386: Improve guest_base handling List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Richard Henderson Cc: qemu-devel@nongnu.org, alex.bennee@linaro.org On Mon, Dec 03, 2018 at 10:08:35 -0600, Richard Henderson wrote: > This tidies guest_base handling such that (1) we require no scratch > registers, (2) we require no extra instructions besides the memory op, > and (3) we reduce the size of the memory op by omitting a prefix. > > In principal point 3 is offset by adding additional opcodes to handle > zero-extension when converting 64-bit guest values back to 32-bit guest > addresses. But those turn out to be hen's teeth, since 32-bit guests > often have no way of even producing 64-bit guest values. > > In particular, I saw none in a simple pass through linux-user-test-0.3 > for i386, arm, sh4, sparc. Reviewed-by: Emilio G. Cota for the series. Thanks, Emilio