On Tue, Sep 23, 2014 at 12:25 PM, Matt Turner <matts...@gmail.com> wrote: > On Fri, Sep 19, 2014 at 1:10 PM, Jason Ekstrand <ja...@jlekstrand.net> wrote: >> Previously, we were generating the fast-clear shader from GLSL. The >> problem is that fast clears require that we use a replicated write rather >> than a regular write instruction. In order to get this we had a >> complicated and somewhat fragile optimization pass that looked for places >> where we can use a replicated write and used it. Since replicated writes >> have a lot of restrictions, we only ever use them for fast-clear >> operations. >> >> This commit replaces the optimization pass with a function that just >> generates the shader we want. This is a) less code, b) less fragile than >> the optimization pass, and c) generates a more efficient shader. >> >> Signed-off-by: Jason Ekstrand <jason.ekstr...@intel.com> >> Cc: Kristian Høgsberg <k...@bitplanet.net>
This looks great, way simpler than before and even a little better in the MRT case. > I think this is probably a good idea, and certainly simplifies things. > It does prevent us from potentially recognizing other non-clear > shaders after optimization though. I don't know all of the state > requirements for using repdata so I don't think I can properly > evaluate the benefit or difficulty in doing that. I'd defer to Ken -- > and pending other comments: The old optimization pass was only enabled when we compiled the fast clear shader, so it would only trigger in that case. The rep write message comes with restrictions on write masks and blending so it would be a bit of work to make the optimization pass work in the general case. Either way, Jasons patch doesn't regress anything: Reviewed-by: Kristian Høgsberg <k...@bitplanet.net> > Reviewed-by: Matt Turner <matts...@gmail.com> > > Also, Cc'ing Kristian, who I don't think has seen this patch yet. _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
