nir/uniform_atomics: fix is_atomic_already_optimized without workgroups

dims_needed would have been zero, so this would always returned true for
non-compute stages.

Also fix this for variable workgroup sizes.

Improves Shadow of the Tomb Raider RX 6800 performance by 10.6%, 11.5% and
4.5% (day_of_dead, jungle and paititi scenes).

radv_perf before and after:
{'app': 'SotTR', 'resolution': '3840x2160', 'preset': 'VeryHigh', 'antialiasing': 'off', 'scene': 'day_of_dead', 'avg_fps': '62.913333333333334', 'min_fps': '62.81', 'max_fps': '62.98', 'interations': '3'}
{'app': 'SotTR', 'resolution': '3840x2160', 'preset': 'VeryHigh', 'antialiasing': 'off', 'scene': 'jungle', 'avg_fps': '64.02666666666666', 'min_fps': '63.93', 'max_fps': '64.11', 'interations': '3'}
{'app': 'SotTR', 'resolution': '3840x2160', 'preset': 'VeryHigh', 'antialiasing': 'off', 'scene': 'paititi', 'avg_fps': '74.81666666666666', 'min_fps': '74.72', 'max_fps': '74.88', 'interations': '3'}

{'app': 'SotTR', 'resolution': '3840x2160', 'preset': 'VeryHigh', 'antialiasing': 'off', 'scene': 'day_of_dead', 'avg_fps': '69.57', 'min_fps': '69.52', 'max_fps': '69.63', 'interations': '3'}
{'app': 'SotTR', 'resolution': '3840x2160', 'preset': 'VeryHigh', 'antialiasing': 'off', 'scene': 'jungle', 'avg_fps': '71.41000000000001', 'min_fps': '71.31', 'max_fps': '71.5', 'interations': '3'}
{'app': 'SotTR', 'resolution': '3840x2160', 'preset': 'VeryHigh', 'antialiasing': 'off', 'scene': 'paititi', 'avg_fps': '78.16666666666667', 'min_fps': '78.07', 'max_fps': '78.23', 'interations': '3'}

Performance now seems slightly better than AMDVLK 2021.Q4.3:
{'app': 'SotTR', 'resolution': '3840x2160', 'preset': 'VeryHigh', 'antialiasing': 'off', 'scene': 'day_of_dead', 'avg_fps': '68.02666666666666', 'min_fps': '67.95', 'max_fps': '68.16', 'interations': '3'}
{'app': 'SotTR', 'resolution': '3840x2160', 'preset': 'VeryHigh', 'antialiasing': 'off', 'scene': 'jungle', 'avg_fps': '70.24666666666667', 'min_fps': '69.83', 'max_fps': '70.51', 'interations': '3'}
{'app': 'SotTR', 'resolution': '3840x2160', 'preset': 'VeryHigh', 'antialiasing': 'off', 'scene': 'paititi', 'avg_fps': '77.19', 'min_fps': '77.18', 'max_fps': '77.2', 'interations': '3'}

fossil-db (Sienna Cichlid):
Totals from 40 (0.03% of 134621) affected shaders:
CodeSize: 62676 -> 65996 (+5.30%)
Instrs: 11372 -> 12111 (+6.50%)
Latency: 144122 -> 142848 (-0.88%); split: -1.09%, +0.21%
InvThroughput: 19686 -> 19847 (+0.82%); split: -0.06%, +0.87%
VClause: 304 -> 306 (+0.66%)
SClause: 603 -> 604 (+0.17%); split: -0.83%, +1.00%
Copies: 780 -> 858 (+10.00%)
Branches: 235 -> 329 (+40.00%)
PreSGPRs: 1072 -> 1083 (+1.03%); split: -0.37%, +1.40%

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14407>

diff --git a/src/compiler/nir/nir_opt_uniform_atomics.c b/src/compiler/nir/nir_opt_uniform_atomics.c
index cdd1319..6746a94 100644 (file)
--- a/src/compiler/nir/nir_opt_uniform_atomics.c
+++ b/src/compiler/nir/nir_opt_uniform_atomics.c
@@ -167,11 +167,16 @@ is_atomic_already_optimized(nir_shader *shader, nir_intrinsic_instr *instr)
       }
    }
 
-   unsigned dims_needed = 0;
-   for (unsigned i = 0; i < 3; i++)
-      dims_needed |= (shader->info.workgroup_size[i] > 1) << i;
+   if (gl_shader_stage_uses_workgroup(shader->info.stage)) {
+      unsigned dims_needed = 0;
+      for (unsigned i = 0; i < 3; i++)
+         dims_needed |= (shader->info.workgroup_size_variable ||
+                         shader->info.workgroup_size[i] > 1) << i;
+      if ((dims & dims_needed) == dims_needed)
+         return true;
+   }
 
-   return (dims & dims_needed) == dims_needed || dims & 0x8;
+   return dims & 0x8;
 }
 
 /* Perform a reduction and/or exclusive scan. */