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Date: Tue, 18 Jan 2011 19:13:35 +0100
From: Stefano Bonifazi <stefboombastic@gmail.com>
MIME-Version: 1.0
Subject: Re: [Qemu-devel] Changing the content of target cpu registers
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To: Blue Swirl <blauwirbel@gmail.com>
Cc: QEMU Developers <qemu-devel@nongnu.org>

On 01/18/2011 06:17 PM, Blue Swirl wrote:
> On Tue, Jan 18, 2011 at 9:29 AM, Stefano Bonifazi
> <stefboombastic@gmail.com>  wrote:
>> Hi all!
>>   I am working on qemu-user (qemu-ppc).
>> I'd like to edit the values of target registers during the execution. Can I
>> do that by simply changing the content of env->gpr[] or do these only
>> contain a copy of the values of the registers?
>> In this last case, where are the real values of the target registers stored
>> so that by modifying them I can alter the behavior of the target code
>> execution?
> env->gpr is the canonical location, but the translator assigns TCG
> variables to them (cpu_gpr[] in translate.c), so GPR contents may be
> cached to these. But when helpers are called or the TB finishes,
> env->gpr should be valid again.
Hi!
  Thank you for your answer!
So if I understand well if I set env->gpr in a code section where there 
is no TCG translation on progress, I can edit directly the target CPU 
register right?
Best Regards!
Stefano B.