Re: [Mesa3d-dev] Evolving the TGSI instruction set

[Keith W. <ke...@vm...>]

On Thu, 2009-12-31 at 05:28 -0800, Christoph Bumiller wrote:
> On 31.12.2009 12:05, Keith Whitwell wrote:
> > Luca,
> >
> > This is an impressive body of work.  I want to give Jose a chance to
> > review the EGL/GLX extensions before pushing, but in the meantime I hope
> > it's ok if I make a couple of quick suggestions/requests:
> >
> > Firstly, we're going to be evolving the TGSI instruction set a fair bit
> > over the coming months to catch up with newer GLSL versions, CL, etc.
> At that point I'd like to ask if, when all the nice memory spaces
> are introduced to TGSI, these nasty indirect accesses to TEMP
> will go away.
> 
> They are really painful to implement because you cannot index
> registers on nv50+ and thus we'd have to regard TEMP as memory.
> And since there is no information in the TGSI tokens about
> what TEMPs constitute an array, we'd have to store and load
> all of them, which would be quite costly.

Yes, I think there will end up being some way in which we mark indexable
ranges of temporaries.

> So I was hoping that, optionally (older cards without actual memory
> won't like it I suppose), the compiler can just generate the
> appropriate stores and loads.

I'm not sure about that.  Can you be more explicit about what you're
having trouble with?

Keith