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To: gdb@sourceware.org
Subject: Re: How to display instructions around the current instuction?
Date: Fri, 29 Jan 2021 17:38:05 -0000 (UTC)
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From: Tavis Ormandy via Gdb <gdb@sourceware.org>
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On 2021-01-28, Andreas Schwab <schwab@linux-m68k.org> wrote:
> On Jan 28 2021, Peng Yu wrote:
>
>> There could be a syntax to go back a given number of instructions.
>
> How do you know how long each instruction is?
>

I just learned about the x/-5i syntax and had the same question. I
didn't look at the code but it does seem to know where the boundaries
are (e.g. if you start in the middle of an instruction).

I guess it must disassemble forward from a previous known location to
learn all the boundaries first?

Tavis.


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