From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Kq8yO-000883-9R for qemu-devel@nongnu.org; Wed, 15 Oct 2008 12:11:44 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1Kq8yL-000878-1W for qemu-devel@nongnu.org; Wed, 15 Oct 2008 12:11:41 -0400 Received: from [199.232.76.173] (port=43190 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Kq8yK-000871-TS for qemu-devel@nongnu.org; Wed, 15 Oct 2008 12:11:40 -0400 Received: from hall.aurel32.net ([88.191.82.174]:38749) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1Kq8yK-0002ol-I0 for qemu-devel@nongnu.org; Wed, 15 Oct 2008 12:11:40 -0400 Received: from anguille.univ-lyon1.fr ([134.214.4.207]) by hall.aurel32.net with esmtpsa (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.63) (envelope-from ) id 1Kq8yF-0006P8-NU for qemu-devel@nongnu.org; Wed, 15 Oct 2008 18:11:35 +0200 Message-ID: <48F61632.2090300@aurel32.net> Date: Wed, 15 Oct 2008 18:11:30 +0200 From: Aurelien Jarno MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH][ppc] reorganize register set for SPE + TCG References: <20081015142237.GN18389@codesourcery.com> In-Reply-To: <20081015142237.GN18389@codesourcery.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Nathan Froyd a écrit : > The (large, invasive) patch below is a preparation patch for converting > (most) SPE instructions to use TCG. The rationale is that your ordinary > SPE instruction deals with three 64-bit quantaties (and a potential > 64-bit accumulator). In the current implementation, it's extremely > laborious/difficult to pass those 64-bit quantaties to helpers, since > the high/low words for SPE registers are not contiguous in the > environment. (TCG helpers for SPE instructions are not yet implemented, > but they will be necessary as part of the total conversion to TCG.) You can pass 64-bit TCG registers to helpers. And you can create one TCG 64-bit value from two 32-bits value if needed, and split it back later. This is exactly what is already done with load_gpr64() and store_gpr64(). Then the limit on the number of arguments of TCG helpers is not a problem anymore. -- .''`. Aurelien Jarno | GPG: 1024D/F1BCDB73 : :' : Debian developer | Electrical Engineer `. `' aurel32@debian.org | aurelien@aurel32.net `- people.debian.org/~aurel32 | www.aurel32.net