On 05/08/2015 03:31 PM, Ian Romanick wrote: > On 05/08/2015 03:25 PM, Jason Ekstrand wrote: >> On Fri, May 8, 2015 at 3:20 PM, Ian Romanick <i...@freedesktop.org> wrote: >>> On 05/08/2015 11:55 AM, Jason Ekstrand wrote: >>>> On Fri, May 8, 2015 at 11:53 AM, Jason Ekstrand <ja...@jlekstrand.net> >>>> wrote: >>>>> total instructions in shared programs: 7152330 -> 7137006 (-0.21%) >>>>> instructions in affected programs: 1330548 -> 1315224 (-1.15%) >>>>> helped: 5797 >>>>> HURT: 76 >>>> >>>> I'm doing some looking into the hurt programs. It seems as if there >>>> are some very strange interatctions between flrp and ffma. I'm still >>>> working out exactly how to fix it up. >>> >>> Yes, I noticed this too. Did you see my reply to Ken earlier today? >>> The problem I noticed /seems/ restricted to cases where the would-be >>> interpolant is scalar but the other values are vector. >> >> It would surprise me a lot of that mattered. At the point where we do >> opt_algebraic in NIR, we've already scalarized things. That said, >> there is a *lot* going on in an optimization loop so anything's >> possible. > > If I take the shader_runner test that I included in the e-mail to Ken > and s/float alpha/vec3 alpha/ I get LRPs. I made some obvious tweaks to > opt_algebraic to handle the mix of scalar and vector, and something like > 150 shaders were helped. > > I spent about an hour digging into it, and I came up dry. I have tried > adding some rules to nir_opt_algebraic.py to convert the fmul/ffma to > flrp, and I couldn't get a break point at the nir_opt_ffma to trigger. > I was going to ask about it at the office on Monday, but it came up on > the list first.
FWIW, those rules were: (('ffma', b, c, ('fmul', a, ('fadd', 1.0, ('fneg', c)))), ('flrp', a, b, c), '!options->lower_flrp'), (('ffma', c, b, ('fmul', a, ('fadd', 1.0, ('fneg', c)))), ('flrp', a, b, c), '!options->lower_flrp'), > _______________________________________________ > mesa-dev mailing list > mesa-dev@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/mesa-dev _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev