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Date: Mon, 18 Aug 2008 13:56:00 -0500
From: Scott Wood <scottwood@freescale.com>
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To: Steven Rostedt <rostedt@goodmis.org>
Subject: Re: ftrace introduces instability into kernel 2.6.27(-rc2,-rc3)
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Cc: Eran Liberty <liberty@extricom.com>,
	Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
	linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org,
	Steven Rostedt <srostedt@redhat.com>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
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Steven Rostedt wrote:
> What syntax to do that with?
> 
>   lwz %1,0(%U2)
>   stu %3, 0(%X2)
> 
> I'm new to those. (and the above does not compile)

lwz%U2%X2 %1, %2
stw%U2%X2 %3, %2

>> Why stwu with an offset of zero,
> 
> How else to do it?  stwu %3, (%2) does not compile for me.

stw %3, 0(%2)

The "u" tells it to write the effective address back to %2 -- but with 
an offset of zero, the effective address is unchanged.

-Scott