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From: Sergio Durigan Junior <sergiodj@sergiodj.net>
To: Luis Machado via Gdb <gdb@sourceware.org>
Cc: Florian Weimer <fweimer@redhat.com>,  Luis Machado via Libc-alpha
 <libc-alpha@sourceware.org>,  Luis Machado <luis.machado@linaro.org>,
 doko@debian.org
Subject: Re: GDB shared library tracking with stap probes x _dl_debug_state
References: <b0b35028-2463-dd00-14af-22be2e7b6ff6@linaro.org>
 <878s4qb7fj.fsf@oldenburg.str.redhat.com>
 <07b03137-a083-dada-68da-965779cd41ff@linaro.org>
X-URL: http://blog.sergiodj.net
Date: Fri, 07 May 2021 17:56:25 -0400
In-Reply-To: <07b03137-a083-dada-68da-965779cd41ff@linaro.org> (Luis Machado
 via Gdb's message of "Fri, 7 May 2021 18:44:47 -0300")
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On Friday, May 07 2021, Luis Machado via Gdb wrote:

> On 5/7/21 5:44 PM, Florian Weimer wrote:
>> * Luis Machado via Libc-alpha:
>> 
>>> That's all fine, but there is one small detail that doesn't work for
>>> armhf, and that is discovering if we're dealing with a PC that is arm
>>> mode or thumb mode.
>> Is it possible to recognize Arm mode vs thumb mode based on the NOP
>> encoding at the probe address?
>> 
>
> If we know the instruction is a NOP, it might be possible.

I think it's guaranteed that the instruction is always going to be a
NOP.

-- 
Sergio
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