From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw02.freescale.net (az33egw02.freescale.net [192.88.158.103]) by ozlabs.org (Postfix) with ESMTP id 940B0679EA for ; Thu, 5 May 2005 04:08:18 +1000 (EST) In-Reply-To: <17016.29775.224816.691409@cargo.ozlabs.ibm.com> References: <17016.29775.224816.691409@cargo.ozlabs.ibm.com> Mime-Version: 1.0 (Apple Message framework v619.2) Content-Type: text/plain; charset=ISO-8859-1; format=flowed Message-Id: <3ef0069e8d123c43579a8cc85d20467c@freescale.com> From: Kumar Gala Date: Wed, 4 May 2005 08:45:51 -0500 To: "Paul Mackerras" Cc: linuxppc-dev@ozlabs.org, trini@kernel.crashing.org Subject: Re: [PATCH] Set cpu explicitly in kernel compiles List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On May 4, 2005, at 2:05 AM, Paul Mackerras wrote: > What do people think of this patch?=A0 The motivation for it is that a > biarch gcc-4.0 will by default tune for POWER4, even for a 32-bit > compile, meaning that we end up with a lot of nops we don't need. > This also takes out -mstring. > > With this, the text size reduces by about 120k for my normal config > when compiling with a biarch gcc-4.0.=A0 The text size also reduces > slightly when compiling with the Debian gcc-3.3.5 (32-bit only, not > biarch). What is attributed to this large of a text size change. I've always=20 assumed the -mcpu and -mtune options really only effected code=20 scheduling. This seems really odd since there arent really that many=20 different instructions between the various PPC variants. - kumar=