[Mesa-dev] TGSI ISA formalization

[Zack Rusin]

> I like the bitwise, flow control, and primitive groups. My main
> concern is splitting things into groups that make it easy to say, "Oh
> yes, this hardware supports all of these opcodes." Also, we have a
> *lot* of opcodes. Any kind of grouping based on the semantics of the
> opcodes is going to be useful.

Why would you want that? Is that useful to anyone? The state trackers
will use the instructions they need whether a group of GPUs supports
it or not, i.e. it's not like they could emulate LOAD.

Besides we can't really do that. We already had a number of discussions
about caps and the outcome each time was that you can't just create a few
groups and expect the hardware to neatly fall into them (while quite frankly I 
never quite agreed with this sentiment, majority has spoken). In any way
the question of which opcodes the given hardware supports is not up to 
gallium docs to define.

I think we can only make it easy for people to understand the instructions
Gallium does provide and for that logical grouping is really the only way
to go.

z