From mboxrd@z Thu Jan 1 00:00:00 1970 From: Weihaw Chuang Date: Mon, 24 Sep 2001 01:43:18 +0000 Subject: [Linux-ia64] differentiating single-step vs taken-branch trap Message-Id: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Hi everyone, I've got two questions, but only the first is really important. 1. I'm using the ptrace kernel interface to trace a child process via single-step or taken-branch traps (through David Mosberger's utrace tool). Is there a way I can use ptrace to allow me to single-step, and in addition observe occurances of taken-branches? It seems that its possible to set the PSR.SS and PSR.TB concurrently, but not a way of differentiating the returned trap signal. All we know upon returning from wait is that a trap occured. Although it seems redundant, as far as I know there is a subtle difference between taken-branch traps and single-step traps. Taken-branch traps return back an IIP value of the branch target, before committing the the results of the target instruction. Single-step traps assign IIP of the committed instruction. The difference is important if I want to look ahead to get register state before a memory operation commits any registers writes. 2. Is there still a ia64 linux kernel mailing list? And is it archived somewhere? Many thanks, -Wei ==************************************************************ Weihaw Chuang wchuang@cs.ucsd.edu ************************************************************ __________________________________________________ Do You Yahoo!? Get email alerts & NEW webcam video instant messaging with Yahoo! Messenger. http://im.yahoo.com