Mesa (main): intel/compiler: Use GCM in nir_optimize

Wed Jul 21 14:48:27 UTC 2021

Module: Mesa
Branch: main
Commit: 9f3fde6f362acb1841e1af634a2e65f3811ca314
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=9f3fde6f362acb1841e1af634a2e65f3811ca314

Author: Timothy Arceri <tarceri at itsqueeze.com>
Date:   Thu Mar 21 16:40:06 2019 +1100

intel/compiler: Use GCM in nir_optimize

There is still some work to do before we can enable GVN.

In these shader-db results, Skylake and older platforms used i965 while
newer platforms used Iris.  I believe this accounts for the difference
in "sends."  The shaders helped for sends are all Synmark shaders.

On Sandybridge, the shaders helped for sends were the same ones hurt for
spills and fills.  These are also all Synmark shaders.

Tiger Lake and Ice Lake had similar results. (Ice Lake shown)
total instructions in shared programs: 19868594 -> 19868452 (<.01%)
instructions in affected programs: 6607 -> 6465 (-2.15%)
helped: 12
HURT: 1
helped stats (abs) min: 12 max: 12 x̄: 12.00 x̃: 12
helped stats (rel) min: 1.94% max: 2.62% x̄: 2.38% x̃: 2.58%
HURT stats (abs)   min: 2 max: 2 x̄: 2.00 x̃: 2
HURT stats (rel)   min: 0.45% max: 0.45% x̄: 0.45% x̃: 0.45%
95% mean confidence interval for instructions value: -13.27 -8.58
95% mean confidence interval for instructions %-change: -2.67% -1.65%
Instructions are helped.

total cycles in shared programs: 962404540 -> 962008224 (-0.04%)
cycles in affected programs: 961274 -> 564958 (-41.23%)
helped: 23
HURT: 1
helped stats (abs) min: 10 max: 32536 x̄: 17438.96 x̃: 23658
helped stats (rel) min: 0.02% max: 80.04% x̄: 42.05% x̃: 51.58%
HURT stats (abs)   min: 4780 max: 4780 x̄: 4780.00 x̃: 4780
HURT stats (rel)   min: 3.26% max: 3.26% x̄: 3.26% x̃: 3.26%
95% mean confidence interval for cycles value: -22989.90 -10036.43
95% mean confidence interval for cycles %-change: -55.01% -25.32%
Cycles are helped.

Skylake and Broadwell had simliar results. (Skylake shown)
total instructions in shared programs: 17996652 -> 17996154 (<.01%)
instructions in affected programs: 96622 -> 96124 (-0.52%)
helped: 85
HURT: 0
helped stats (abs) min: 1 max: 12 x̄: 5.86 x̃: 5
helped stats (rel) min: 0.39% max: 2.65% x̄: 0.68% x̃: 0.39%
95% mean confidence interval for instructions value: -6.42 -5.30
95% mean confidence interval for instructions %-change: -0.84% -0.52%
Instructions are helped.

total cycles in shared programs: 939899189 -> 939289732 (-0.06%)
cycles in affected programs: 3719430 -> 3109973 (-16.39%)
helped: 60
HURT: 39
helped stats (abs) min: 18 max: 32444 x̄: 10437.30 x̃: 6940
helped stats (rel) min: 0.08% max: 80.40% x̄: 23.99% x̃: 12.07%
HURT stats (abs)   min: 10 max: 4970 x̄: 430.28 x̃: 323
HURT stats (rel)   min: 0.05% max: 3.41% x̄: 1.55% x̃: 1.60%
95% mean confidence interval for cycles value: -8095.51 -4216.75
95% mean confidence interval for cycles %-change: -18.65% -9.21%
Cycles are helped.

total sends in shared programs: 1026997 -> 1026927 (<.01%)
sends in affected programs: 6090 -> 6020 (-1.15%)
helped: 70
HURT: 0
helped stats (abs) min: 1 max: 1 x̄: 1.00 x̃: 1
helped stats (rel) min: 1.15% max: 1.15% x̄: 1.15% x̃: 1.15%
95% mean confidence interval for sends value: -1.00 -1.00
95% mean confidence interval for sends %-change: -1.15% -1.15%
Sends are helped.

Haswell and Ivy Bridge had similar results. (Haswell shown)
total instructions in shared programs: 16040891 -> 16040252 (<.01%)
instructions in affected programs: 109132 -> 108493 (-0.59%)
helped: 87
HURT: 0
helped stats (abs) min: 1 max: 12 x̄: 7.34 x̃: 7
helped stats (rel) min: 0.05% max: 2.61% x̄: 0.75% x̃: 0.51%
95% mean confidence interval for instructions value: -7.84 -6.85
95% mean confidence interval for instructions %-change: -0.90% -0.61%
Instructions are helped.

total cycles in shared programs: 968579567 -> 967867117 (-0.07%)
cycles in affected programs: 30688439 -> 29975989 (-2.32%)
helped: 241
HURT: 62
helped stats (abs) min: 4 max: 31929 x̄: 3901.22 x̃: 2282
helped stats (rel) min: 0.04% max: 79.63% x̄: 12.70% x̃: 4.44%
HURT stats (abs)   min: 4 max: 8230 x̄: 3673.27 x̃: 637
HURT stats (rel)   min: 0.01% max: 63.87% x̄: 24.54% x̃: 3.56%
95% mean confidence interval for cycles value: -3100.23 -1602.41
95% mean confidence interval for cycles %-change: -7.94% -2.22%
Cycles are helped.

total sends in shared programs: 935025 -> 934955 (<.01%)
sends in affected programs: 6090 -> 6020 (-1.15%)
helped: 70
HURT: 0
helped stats (abs) min: 1 max: 1 x̄: 1.00 x̃: 1
helped stats (rel) min: 1.15% max: 1.15% x̄: 1.15% x̃: 1.15%
95% mean confidence interval for sends value: -1.00 -1.00
95% mean confidence interval for sends %-change: -1.15% -1.15%
Sends are helped.

LOST:   1
GAINED: 0

Sandy Bridge
total instructions in shared programs: 11785330 -> 11786504 (<.01%)
instructions in affected programs: 53462 -> 54636 (2.20%)
helped: 16
HURT: 36
helped stats (abs) min: 1 max: 17 x̄: 10.06 x̃: 9
helped stats (rel) min: 0.47% max: 3.29% x̄: 2.03% x̃: 1.90%
HURT stats (abs)   min: 5 max: 38 x̄: 37.08 x̃: 38
HURT stats (rel)   min: 1.77% max: 2.98% x̄: 2.94% x̃: 2.98%
95% mean confidence interval for instructions value: 16.26 28.90
95% mean confidence interval for instructions %-change: 0.75% 2.08%
Instructions are HURT.

total cycles in shared programs: 498009911 -> 497378300 (-0.13%)
cycles in affected programs: 6848277 -> 6216666 (-9.22%)
helped: 108
HURT: 28
helped stats (abs) min: 4 max: 25394 x̄: 6037.42 x̃: 766
helped stats (rel) min: 0.02% max: 60.58% x̄: 11.60% x̃: 4.83%
HURT stats (abs)   min: 96 max: 6834 x̄: 729.64 x̃: 742
HURT stats (rel)   min: 0.17% max: 16.23% x̄: 1.57% x̃: 1.55%
95% mean confidence interval for cycles value: -5907.99 -3380.40
95% mean confidence interval for cycles %-change: -11.67% -6.11%
Cycles are helped.

total spills in shared programs: 2316 -> 2526 (9.07%)
spills in affected programs: 280 -> 490 (75.00%)
helped: 0
HURT: 35

total fills in shared programs: 1540 -> 1750 (13.64%)
fills in affected programs: 280 -> 490 (75.00%)
helped: 0
HURT: 35

total sends in shared programs: 642985 -> 642950 (<.01%)
sends in affected programs: 3045 -> 3010 (-1.15%)
helped: 35
HURT: 0
helped stats (abs) min: 1 max: 1 x̄: 1.00 x̃: 1
helped stats (rel) min: 1.15% max: 1.15% x̄: 1.15% x̃: 1.15%
95% mean confidence interval for sends value: -1.00 -1.00
95% mean confidence interval for sends %-change: -1.15% -1.15%
Sends are helped.

LOST:   1
GAINED: 0

Iron Lake and GM45 had similar results. (Iron Lake shown)
total cycles in shared programs: 239442382 -> 239429400 (<.01%)
cycles in affected programs: 20816 -> 7834 (-62.37%)
helped: 2
HURT: 0

In Fossil-db, all of the shaders hurt for spill and fills are compute
shaders from Shadow of the Tomb Raider.  Two shaders were helped for
sends, and these are also from SotTR.

All of the shaders helped for loops were from Geekbench5.  These all
went from 3 loops to 2.

Tiger Lake
Instructions in all programs: 160852396 -> 160855303 (+0.0%)
SENDs in all programs: 6878559 -> 6878559 (+0.0%)
Loops in all programs: 38350 -> 38305 (-0.1%)
Cycles in all programs: 7369162339 -> 7344236445 (-0.3%)
Spills in all programs: 193762 -> 193876 (+0.1%)
Fills in all programs: 306417 -> 306600 (+0.1%)

Ice Lake
Instructions in all programs: 144592523 -> 144593946 (+0.0%)
SENDs in all programs: 6930697 -> 6930697 (+0.0%)
Loops in all programs: 38344 -> 38299 (-0.1%)
Cycles in all programs: 8732456458 -> 8707823383 (-0.3%)
Spills in all programs: 216692 -> 216806 (+0.1%)
Fills in all programs: 334089 -> 334272 (+0.1%)

Skylake
Instructions in all programs: 135618746 -> 135619971 (+0.0%)
SENDs in all programs: 6896728 -> 6896724 (-0.0%)
Loops in all programs: 38343 -> 38298 (-0.1%)
Cycles in all programs: 8391957144 -> 8368935657 (-0.3%)
Spills in all programs: 194741 -> 194879 (+0.1%)
Fills in all programs: 301048 -> 301255 (+0.1%)

Reviewed-by: Kenneth Graunke <kenneth at whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/597>

---

 src/intel/compiler/brw_nir.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/intel/compiler/brw_nir.c b/src/intel/compiler/brw_nir.c
index 37da6965ba3..76bfa7d93c9 100644
--- a/src/intel/compiler/brw_nir.c
+++ b/src/intel/compiler/brw_nir.c
@@ -674,6 +674,7 @@ brw_nir_optimize(nir_shader *nir, const struct brw_compiler *compiler,
          OPT(nir_opt_loop_unroll, loop_indirect_mask);
       }
       OPT(nir_opt_remove_phis);
+      OPT(nir_opt_gcm, false);
       OPT(nir_opt_undef);
       OPT(nir_lower_pack);
    } while (progress);

