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From: Daniel Jacobowitz <drow@false.org>
To: Nicholas Mc Guire <mcguire@lzu.edu.cn>
Cc: gdb@sources.redhat.com
Subject: Re: bytecode question
Date: Sun, 16 Apr 2006 23:33:00 -0000	[thread overview]
Message-ID: <20060416155220.GA25756@nevyn.them.org> (raw)
In-Reply-To: <200604161457.k3GEvZbm004592@opentech.lzu.edu.cn>

On Sun, Apr 16, 2006 at 10:57:35PM +0800, Nicholas Mc Guire wrote:
> tracepoint 1 triggert at 80483f2
> found 1 actions for this tp
> action length 13, code 26000422000222040322040c27
> collecting reg 4 = befef5e4
> Trace at befef5e0 (size 4)
> dump size 4, data 00000000
> bc done
> 
> Child exited with retcode = 0
> 
> 
> 
> The interpreter loop:
> 
>  removed all the cases not needed here - the post is overly long allreadyi
>  sorry for that.
>  My suspicion is that the way I'm collecting the registers in case 0x26 
>  (bytecode register) is collecting the wrong register content in this case
>  (value 0x4 is sp on x86) - any idea what could be wrong here ?
>  I called set_desired_inferior in the entry function (the tracepoint handler)
>  that then called dump_bytecode - must one do anything more to get hold of
>  the registers of the application being traced ?

Why do you think that something is wrong with the register values? 
That looks to me like a sane stack pointer.

I gather from the context that you're doing this in gdbserver.  It
could be anything; you may have stale registers from the last stop.
I recommend understanding how this works in the normal stop/start
case and where the register cache gets updated.

-- 
Daniel Jacobowitz
CodeSourcery

      reply	other threads:[~2006-04-16 15:52 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-04-16 23:16 Nicholas Mc Guire
2006-04-16 23:33 ` Daniel Jacobowitz [this message]

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