From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Mosberger Date: Tue, 27 May 2003 18:56:20 +0000 Subject: Re: [Linux-ia64] run time code generation for IA-64 Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org >>>>> On Wed, 28 May 2003 00:17:42 +0530 (IST), CH Gowri Kumar said: CH> Hi David, >> Where do you have R4 and R5 before using them? CH> Did you mean to say that I have to save R4 and R5 before using them? Yes, of course: "preserved" means you have to save a register before using it. On the positive side, it's contents will get preserved across calls. CH> Just wondering why isn't there a standard calling convention on IA-64. CH> Something of this sort(if at all to be saved): CH> rp has to be saved in loc0 CH> sp has to be saved in loc1 CH> gp has to be saved in loc2 That would needlessly constrain code optimization. For example, on ia64, it's almost never necessary to save sp. --david