From b416c08e86953e947654283c0b2ef10f9589f007 Mon Sep 17 00:00:00 2001
From: Rob Clark <robdclark@chromium.org>
Date: Thu, 20 Oct 2022 17:49:21 -0700
Subject: [PATCH] freedreno/ir3: Drop unused view_zero/layer_zero lowering

Previous patch removed the only remaining user.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19236>
---
 src/freedreno/ir3/ir3_nir.c    | 60 ----------------------------------
 src/freedreno/ir3/ir3_shader.c |  8 -----
 src/freedreno/ir3/ir3_shader.h | 10 ------
 3 files changed, 78 deletions(-)

diff --git a/src/freedreno/ir3/ir3_nir.c b/src/freedreno/ir3/ir3_nir.c
index 266955298b9..c2c1acf5d5f 100644
--- a/src/freedreno/ir3/ir3_nir.c
+++ b/src/freedreno/ir3/ir3_nir.c
@@ -588,59 +588,6 @@ ir3_nir_post_finalize(struct ir3_shader *shader)
    ir3_optimize_loop(compiler, s);
 }
 
-static bool
-ir3_nir_lower_view_layer_id(nir_shader *nir, bool layer_zero, bool view_zero)
-{
-   unsigned layer_id_loc = ~0, view_id_loc = ~0;
-   nir_foreach_shader_in_variable (var, nir) {
-      if (var->data.location == VARYING_SLOT_LAYER)
-         layer_id_loc = var->data.driver_location;
-      if (var->data.location == VARYING_SLOT_VIEWPORT)
-         view_id_loc = var->data.driver_location;
-   }
-
-   assert(!layer_zero || layer_id_loc != ~0);
-   assert(!view_zero || view_id_loc != ~0);
-
-   bool progress = false;
-   nir_builder b;
-
-   nir_foreach_function (func, nir) {
-      nir_builder_init(&b, func->impl);
-
-      nir_foreach_block (block, func->impl) {
-         nir_foreach_instr_safe (instr, block) {
-            if (instr->type != nir_instr_type_intrinsic)
-               continue;
-
-            nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
-
-            if (intrin->intrinsic != nir_intrinsic_load_input)
-               continue;
-
-            unsigned base = nir_intrinsic_base(intrin);
-            if (base != layer_id_loc && base != view_id_loc)
-               continue;
-
-            b.cursor = nir_before_instr(&intrin->instr);
-            nir_ssa_def *zero = nir_imm_int(&b, 0);
-            nir_ssa_def_rewrite_uses(&intrin->dest.ssa, zero);
-            nir_instr_remove(&intrin->instr);
-            progress = true;
-         }
-      }
-
-      if (progress) {
-         nir_metadata_preserve(
-            func->impl, nir_metadata_block_index | nir_metadata_dominance);
-      } else {
-         nir_metadata_preserve(func->impl, nir_metadata_all);
-      }
-   }
-
-   return progress;
-}
-
 static bool
 lower_ucp_vs(struct ir3_shader_variant *so)
 {
@@ -707,15 +654,8 @@ ir3_nir_lower_variant(struct ir3_shader_variant *so, nir_shader *s)
    if (lower_ucp_vs(so)) {
       progress |= OPT(s, nir_lower_clip_vs, so->key.ucp_enables, false, true, NULL);
    } else if (s->info.stage == MESA_SHADER_FRAGMENT) {
-      bool layer_zero =
-         so->key.layer_zero && (s->info.inputs_read & VARYING_BIT_LAYER);
-      bool view_zero =
-         so->key.view_zero && (s->info.inputs_read & VARYING_BIT_VIEWPORT);
-
       if (so->key.ucp_enables && !so->compiler->has_clip_cull)
          progress |= OPT(s, nir_lower_clip_fs, so->key.ucp_enables, true);
-      if (layer_zero || view_zero)
-         progress |= OPT(s, ir3_nir_lower_view_layer_id, layer_zero, view_zero);
    }
 
    /* Move large constant variables to the constants attached to the NIR
diff --git a/src/freedreno/ir3/ir3_shader.c b/src/freedreno/ir3/ir3_shader.c
index 049b5d7f184..02e615c438f 100644
--- a/src/freedreno/ir3/ir3_shader.c
+++ b/src/freedreno/ir3/ir3_shader.c
@@ -507,14 +507,6 @@ ir3_setup_used_key(struct ir3_shader *shader)
          key->rasterflat = true;
       }
 
-      if (info->inputs_read & VARYING_BIT_LAYER) {
-         key->layer_zero = true;
-      }
-
-      if (info->inputs_read & VARYING_BIT_VIEWPORT) {
-         key->view_zero = true;
-      }
-
       /* Only used for deciding on behavior of
        * nir_intrinsic_load_barycentric_sample and the centroid demotion
        * on older HW.
diff --git a/src/freedreno/ir3/ir3_shader.h b/src/freedreno/ir3/ir3_shader.h
index a97a65a797a..726a3cab3dc 100644
--- a/src/freedreno/ir3/ir3_shader.h
+++ b/src/freedreno/ir3/ir3_shader.h
@@ -324,13 +324,6 @@ struct ir3_shader_key {
           * the limit:
           */
          unsigned safe_constlen : 1;
-
-         /* Whether gl_Layer must be forced to 0 because it isn't written. */
-         unsigned layer_zero : 1;
-
-         /* Whether gl_ViewportIndex must be forced to 0 because it isn't
-          * written. */
-         unsigned view_zero : 1;
       };
       uint32_t global;
    };
@@ -403,9 +396,6 @@ ir3_shader_key_changes_fs(struct ir3_shader_key *key,
    if (last_key->rasterflat != key->rasterflat)
       return true;
 
-   if (last_key->layer_zero != key->layer_zero)
-      return true;
-
    if (last_key->ucp_enables != key->ucp_enables)
       return true;