nir/schedule: use larger delay for non-filtered memory reads

This has been pending for a long time. It is not very consistent to
add a significant delay for textures and not do it for UBOs, etc
The reason we have not been doing this so far is the accumulated effect
on register pressure for V3D as shown by shader-db results below, but
from the point of view of a generic scheduler it makes sense to do this.

Later patches will address V3D specific issues with register pressure
derived from this by letting the driver control its instruction delay
settings.

total instructions in shared programs: 12662138 -> 13126587 (3.67%)
instructions in affected programs: 1813091 -> 2277540 (25.62%)
helped: 2410
HURT: 10499

total threads in shared programs: 415858 -> 407208 (-2.08%)
threads in affected programs: 17348 -> 8698 (-49.86%)
helped: 8
HURT: 4333

total uniforms in shared programs: 3711483 -> 3812698 (2.73%)
uniforms in affected programs: 128012 -> 229227 (79.07%)
helped: 3474
HURT: 2143

total max-temps in shared programs: 2138763 -> 2318430 (8.40%)
max-temps in affected programs: 318780 -> 498447 (56.36%)
helped: 588
HURT: 11997

total spills in shared programs: 3860 -> 49086 (1171.66%)
spills in affected programs: 709 -> 45935 (6378.84%)
helped: 23
HURT: 1595

total fills in shared programs: 5573 -> 55810 (901.44%)
fills in affected programs: 1067 -> 51304 (4708.25%)
helped: 23
HURT: 1595

LOST:   3
GAINED: 0

Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15276>

diff --git a/src/broadcom/compiler/nir_to_vir.c b/src/broadcom/compiler/nir_to_vir.c
index 2855904..7125c35 100644 (file)
--- a/src/broadcom/compiler/nir_to_vir.c
+++ b/src/broadcom/compiler/nir_to_vir.c
@@ -2158,7 +2158,7 @@ v3d_optimize_nir(struct v3d_compile *c, struct nir_shader *s)
 
         nir_move_options sink_opts =
                 nir_move_const_undef | nir_move_comparisons | nir_move_copies |
-                nir_move_load_ubo | nir_move_load_uniform;
+                nir_move_load_ubo | nir_move_load_ssbo | nir_move_load_uniform;
         NIR_PASS(progress, s, nir_opt_sink, sink_opts);
 }
 

diff --git a/src/compiler/nir/nir_schedule.c b/src/compiler/nir/nir_schedule.c
index 025a6d7..d9aca42 100644 (file)
--- a/src/compiler/nir/nir_schedule.c
+++ b/src/compiler/nir/nir_schedule.c
@@ -1016,8 +1016,17 @@ nir_schedule_get_delay(nir_instr *instr)
       return 1;
 
    case nir_instr_type_intrinsic:
-      /* XXX: Pick a large number for UBO/SSBO/image/shared loads */
-      return 1;
+      switch (nir_instr_as_intrinsic(instr)->intrinsic) {
+      case nir_intrinsic_load_ubo:
+      case nir_intrinsic_load_ssbo:
+      case nir_intrinsic_load_scratch:
+      case nir_intrinsic_load_shared:
+      case nir_intrinsic_image_load:
+         return 50;
+      default:
+         return 1;
+      }
+      break;
 
    case nir_instr_type_tex:
       /* Pick some large number to try to fetch textures early and sample them