[Mesa-dev] r600g plans

[Tom Stellard]

On Fri, Jul 23, 2010 at 08:09:46PM -0400, Jerome Glisse wrote:
> On 07/23/2010 07:11 PM, Corbin Simpson wrote:
> > On Fri, Jul 23, 2010 at 3:49 PM, Jerome Glisse<glisse at freedesktop.org>  wrote:
> >> Just heads up on r600g plan, i removed the compiler stuff it was getting
> >> messy
> >> and kind of stopped anyone else from working on other part of r600g. So now
> >> there
> >> is a very simple&  dumb tgsi ->  r600 assembler that does work and can run
> >> glxgears
> >> and couple others non textured demos. I want to freeze r600_asm* stuff as i
> >> plan
> >> to reuse at latter point with a proper optimizer (thought there is a couple
> >> of
> >> thing missing in it like splitting alu node when reaching the 256dwords
> >> limit).
> >> So now if you want to add opcode the only file you need to touch is
> >> r600_shader.c.
> >> Also i would like to avoid any kind of work on optimizing what it spit.
> >>
> >> I am going to add texture support over the next few days (target being
> >> tri-tex,
> >> multiarb, tunnel, tunnel2 at that point i think quake engine should run).
> >>
> >> Todo list (kind of sorted):
> >> - texture support
> >> - use const buffer rather than cfile
> >> - avoid recompiling the shader at each draw command (would improve speed a
> >>   lot)
> >> - stencil support
> >> - support more states (blending, alpha, rasterization, ...)
> >> - geometry shader
> >> - tiling support
> >> - color mask support
> >> - hyperz
> >> - a proper compiler
> >>
> >> Feel free to pick something and have fun.
> >
> > You're awesome as usual. Can we talk about maybe some common
> > optimizations to r300g and r600g (and maybe others) that can be done
> > in TGSI? Code sharing is fun, and I *really* don't want to see
> > features fall by the wayside just because the shader compiler needs
> > work.
> >
> > ~ C.
> >
> 
> When i first looked at optimization i looked at r300 compiler, but
> thing is i want to try a different approach that would be very hard
> to apply to r300-r500 hw. Basic idea is to do all optimization as
> scalar, and repack the instruction after. The repacking is more or
> less easy on r6xx and after but it's really tricky on r3xx-r5xx.
>

Two Questions:

1. You mentioned in another mail message that you have started working on a
r600g compiler.  Is this working being done in its own branch somewhere?

2. Have you considered using SSA form once you've converted everything to
scalar?

-Tom