<div dir="ltr"><div class="gmail_quote"><div dir="ltr">On Thu, Oct 18, 2018 at 3:11 PM Ian Romanick <<a href="mailto:idr@freedesktop.org">idr@freedesktop.org</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On 10/17/2018 11:33 AM, Jason Ekstrand wrote: > From: Connor Abbott <<a href="mailto:cwabbott0@gmail.com" target="_blank">cwabbott0@gmail.com</a>> > > Shader-db results on Haswell: > > total instructions in shared programs: 2180337 -> 2154080 (-1.20%) > instructions in affected programs: 959766 -> 933509 (-2.74%) > helped: 5653 > HURT: 2560 > > total cycles in shared programs: 12339326 -> 12307102 (-0.26%) > cycles in affected programs: 6102794 -> 6070570 (-0.53%) > helped: 3838 > HURT: 4868 Here's the results I got with these 3 patches on 322a919a41f: total instructions in shared programs: 13674046 -> 13643001 (-0.23%) instructions in affected programs: 1248672 -> 1217627 (-2.49%) helped: 7168 HURT: 2841 helped stats (abs) min: 1 max: 39 x̄: 5.40 x̃: 3 helped stats (rel) min: 0.21% max: 33.33% x̄: 4.55% x̃: 3.54% HURT stats (abs) min: 1 max: 21 x̄: 2.71 x̃: 3 HURT stats (rel) min: 0.19% max: 22.73% x̄: 3.86% x̃: 3.53% 95% mean confidence interval for instructions value: -3.23 -2.97 95% mean confidence interval for instructions %-change: -2.28% -2.05% Instructions are helped. total cycles in shared programs: 373694400 -> 373745788 (0.01%) cycles in affected programs: 23171532 -> 23222920 (0.22%) helped: 4890 HURT: 5632 helped stats (abs) min: 2 max: 1268 x̄: 52.04 x̃: 34 helped stats (rel) min: 0.04% max: 45.71% x̄: 7.43% x̃: 4.64% HURT stats (abs) min: 2 max: 6042 x̄: 54.30 x̃: 32 HURT stats (rel) min: 0.05% max: 60.66% x̄: 8.19% x̃: 6.21% 95% mean confidence interval for cycles value: 1.30 8.47 95% mean confidence interval for cycles %-change: 0.73% 1.14% Cycles are HURT. total spills in shared programs: 82569 -> 82572 (<.01%) spills in affected programs: 70 -> 73 (4.29%) helped: 0 HURT: 3 total fills in shared programs: 93445 -> 93449 (<.01%) fills in affected programs: 71 -> 75 (5.63%) helped: 0 HURT: 4 This is pretty different from your result... and not good. :( What SHA of master were you on? </blockquote><div> </div><div>For one thing, I scrubbed all the non-vec4 programs from the results because this doesn't affect FS. I'm not sure what master; something from the last two days; I just rebased. Maybe you have a newer shader-db? </div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> > Most of the hurt programs seem to be because we generate extra MOV's due > to vectorizing things. For example, in > shaders/non-free/steam/anomaly-2/158.shader_test, this: > > add(8) g116<1>.xyF g12<4,4,1>.xyyyF g1.4<0,4,1>.xyyyF { align16 NoDDClr 1Q }; > add(8) g117<1>.xyF g12<4,4,1>.xyyyF g1.4<0,4,1>.zwwwF { align16 NoDDClr 1Q }; > add(8) g116<1>.zwF g12<4,4,1>.xxxyF -g1.4<0,4,1>.xxxyF { align16 NoDDChk 1Q }; > add(8) g117<1>.zwF g12<4,4,1>.xxxyF -g1.4<0,4,1>.zzzwF { align16 NoDDChk 1Q }; > > Turns into this: > > add(8) g13<1>F g12<4,4,1>.xyxyF g1.4<0,4,1>F { align16 1Q }; > add(8) g14<1>F g12<4,4,1>.xyxyF -g1.4<0,4,1>F { align16 1Q }; > mov(8) g116<1>.xyD g13<4,4,1>.xyyyD { align16 NoDDClr 1Q }; > mov(8) g117<1>.xyD g13<4,4,1>.zwwwD { align16 NoDDClr 1Q }; > mov(8) g116<1>.zwD g14<4,4,1>.xxxyD { align16 NoDDChk 1Q }; > mov(8) g117<1>.zwD g14<4,4,1>.zzzwD { align16 NoDDChk 1Q }; > > So we eliminated two add's, but then had to introduce four mov's to > transpose the result. Some of the hurt is because vectorization is a bit > over-aggressive and we vectorize something when we should have left it > as a scalar and CSEd it. Unfortunately, this is all really tricky to do > as it involves the interactions between many different components. > --- > src/intel/compiler/brw_nir.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/src/intel/compiler/brw_nir.c b/src/intel/compiler/brw_nir.c > index 297845b89b7..564fd004a94 100644 > --- a/src/intel/compiler/brw_nir.c > +++ b/src/intel/compiler/brw_nir.c > @@ -568,6 +568,12 @@ brw_nir_optimize(nir_shader *nir, const struct brw_compiler *compiler, > OPT(nir_copy_prop); > OPT(nir_opt_dce); > OPT(nir_opt_cse); > + > + if (!is_scalar) { > + OPT(nir_opt_vectorize); > + OPT(nir_copy_prop); > + } > + > OPT(nir_opt_peephole_select, 0); > OPT(nir_opt_intrinsics); > OPT(nir_opt_algebraic); > </blockquote></div></div>