[patch] split FRAME variables back into pieces

[Martin Jambor]

Hi,

On Fri, Sep 21, 2012 at 12:48:16PM +0200, Eric Botcazou wrote:
>

...

> > As of doing it in SRA what I'd do there is special-case FRAME for both
> > candidate consideration (so you get around the addressable issue)
> > and replacement generation.
> 
> OK, but you need to be able to split the FRAME structure without necessarily 
> splitting its aggregate fields.  Is that (easily) doable with current SRA?
> 

Well, the current code assumes that the replacements are gimple
register types and, perhaps more importantly, it assumes there are no
to-be-replaced pieces within to-be-replaced pieces.  If we were to put
a structure outside of a frame structure and scalarize some field
within it at the same time... a lot of places would probably need to
be slightly re-thought.  OTOH, I assume the frame structure is never
being assigned to or read as a whole so that would simplify a lot of
things.

> > Maybe you can open an enhancement bugreport for this and link
> > your patch / testcase to it?
> 
> Will do.

Please CC me in the bug.  I probably won't be able to try anything
myself for a few weeks but I'm interested in helping.

Thanks,

Martin