Re: PATCH: Extend gdb remote protocol for AVX

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Sat, Oct 4, 2008 at 3:13 PM, Daniel Jacobowitz <dan@codesourcery.com> wrote:
>> I have no objection to the changes you proposed for the remote
>> protocol.  But your diff also touches the core register stuff, and
>> that needs a bit more thought to make sure we don't surprise our
>> users.  At that point, it may be easier to use the same model for the
>> remote protocol, where you transfer the top 128 bits of the %ymm
>> registers in addition to the %xmm registers.  Adter all this is how
>> the hardware does it too (xsave is just an extension of fxsave).
>
> One way would be to transfer the xmm registers and then the remaining
> bits as unnamed registers; another, probably easier way would be to
> use an architecture specification or an actual register description to
> transfer just the ymm registers and let GDB know about that fact, so
> it can synthesize the xmm registers.
>
> (I don't remember the original patch, that may be what you're talking
> about already.)
>

My proposal transfers the whole 256bit registers.  We can display
xmm registers as the lower 128bit ymm registers if we can
display al/ax/eax.



-- 
H.J.