[Mesa-dev] [PATCH 8/8] gallium: remove TGSI opcode KILL

[Marek Olšák]

On Sun, Aug 20, 2017 at 4:29 AM, Roland Scheidegger <sroland at vmware.com> wrote:
> For 1-3/8, I don't think anything ever used these, and 5/8 (DPH) we
> don't need neither, so
> Reviewed-by: Roland Scheidegger <sroland at vmware.com>
>
> 4,6,7, well we can live fine without them, just translating them away
> the same as you do here too. (I thought some hw could do them natively,
> hence the driver would have to recognize them to get optimal results,
> but if they aren't emitted anyway who cares.)
>
> Can we keep KILL though please? From a shader api cleanness point of
> view, I'd rather have this simple instruction than upgrading it to a
> rather complex instruction involving per-channel float comparisons (plus
> combining the results), even if it's trivial to do so and the compiler
> should be able to throw out all the conditional mess.
> From a conceptual point of view, we don't have conditional ret, cont,
> etc. neither (much less ones which use built-in per channel float
> comparisons...). Probably nuking KILL_IF instead isn't a good idea (as
> this really translates to old-style kill) so IMHO we should just keep both.
> (But you can really kill breakc if you want - that's going to be less
> work than any of the dp2a/xpd/scs ones here :-)).

Yeah, I can keep KILL and then kill BREAKC.

XPD etc. were really trivial. There is only one or two places that
need to unwind the instructions. The rest is just removed code.

Marek