pan/mdg: Scalarize LUT instructions in NIR

Simpler. Small shaderdb regressions from using IR registers instead of SSA, but that's probably what we needed for correctness (given that SSA is violated otherwise) hence the Cc.

total instructions in shared programs: 99879 -> 99906 (0.03%) instructions in affected programs: 3260 -> 3287 (0.83%) helped: 13 HURT: 21 helped stats (abs) min: 2.0 max: 4.0 x̄: 2.77 x̃: 2 helped stats (rel) min: 1.03% max: 19.05% x̄: 8.62% x̃: 2.70% HURT stats (abs) min: 1.0 max: 9.0 x̄: 3.00 x̃: 2 HURT stats (rel) min: 0.73% max: 8.22% x̄: 3.24% x̃: 1.94% 95% mean confidence interval for instructions value: -0.40 1.99 95% mean confidence interval for instructions %-change: -4.11% 1.52% Inconclusive result (value mean confidence interval includes 0).

total bundles in shared programs: 43778 -> 43766 (-0.03%) bundles in affected programs: 1235 -> 1223 (-0.97%) helped: 17 HURT: 15 helped stats (abs) min: 1.0 max: 4.0 x̄: 1.82 x̃: 2 helped stats (rel) min: 1.25% max: 22.22% x̄: 8.73% x̃: 3.85% HURT stats (abs) min: 1.0 max: 3.0 x̄: 1.27 x̃: 1 HURT stats (rel) min: 2.50% max: 25.00% x̄: 5.60% x̃: 3.12% 95% mean confidence interval for bundles value: -0.99 0.24 95% mean confidence interval for bundles %-change: -5.79% 1.77% Inconclusive result (value mean confidence interval includes 0).

total quadwords in shared programs: 76783 -> 76807 (0.03%) quadwords in affected programs: 2606 -> 2630 (0.92%) helped: 16 HURT: 18 helped stats (abs) min: 2.0 max: 4.0 x̄: 3.00 x̃: 3 helped stats (rel) min: 1.38% max: 22.22% x̄: 8.54% x̃: 2.91% HURT stats (abs) min: 1.0 max: 15.0 x̄: 4.00 x̃: 1 HURT stats (rel) min: 0.57% max: 17.86% x̄: 6.49% x̃: 4.17% 95% mean confidence interval for quadwords value: -1.00 2.42 95% mean confidence interval for quadwords %-change: -4.40% 3.23% Inconclusive result (value mean confidence interval includes 0).

total registers in shared programs: 7266 -> 7266 (0.00%) registers in affected programs: 50 -> 50 (0.00%) helped: 4 HURT: 4 helped stats (abs) min: 1.0 max: 1.0 x̄: 1.00 x̃: 1 helped stats (rel) min: 12.50% max: 33.33% x̄: 19.20% x̃: 15.48% HURT stats (abs) min: 1.0 max: 1.0 x̄: 1.00 x̃: 1 HURT stats (rel) min: 12.50% max: 20.00% x̄: 16.25% x̃: 16.25% 95% mean confidence interval for registers value: -0.89 0.89 95% mean confidence interval for registers %-change: -18.33% 15.38% Inconclusive result (value mean confidence interval includes 0).

total threads in shared programs: 4956 -> 4954 (-0.04%) threads in affected programs: 4 -> 2 (-50.00%) helped: 0 HURT: 2

Cc: mesa-stable Signed-off-by: Alyssa Rosenzweig alyssa@rosenzweig.io