Re: [commit] Fix Xtensa-specific bug in MI command

[Maxim Grigoriev <maxim at tensilica dot com>]

On 03/08/2011 07:51 PM, Joel Brobecker wrote:
> > Fix Xtensa-specific bug in MI command -data-list-changed-registers.
> >      
> A small request: If you could give more details with your patches
> about what you are fixing.  For the previous ones, there wasn't
> much to add, just extending support for new features.  But for this
> one, it would have been helpful to know what type of bug it was.
> For instance, a transcript showing the issue can be useful to
> other people hitting the problem, and doing an internet search.
>
>    
Eclipse CDT uses this MI command to get a list of changed
registers compared to the previous register file state saved before.
It happens, when Eclipse user opens a register display window.
After each new event in the debugging session, such as "step",
"next" ( which lead to executing some instruction(s) on the target ),
updated registers are high-lighted in that display window.

MI command  -data-list-changed-registers uses generic hook

     gdbarch_register_reggroup_p ()

to analyse updates to the register file.

Registers from standard GDB group "save_reggroup" have
to be always a part of this analysis.

It's been missing on Xtensa. That's why changed registers
did not always display  properly in the Eclipse register
display window.

Thanks for your notes and suggestions,
-- Maxim Grigoriev

Tensilica, Inc.
Santa Clara, CA
408-566-1770