commit ea77958fea2b358a9b3de0bf5022e5c72ef63064
author Marek Olšák <marek.olsak@amd.com> Thu Sep 17 20:25:22 2020 -0400
committer Marek Olšák <marek.olsak@amd.com> Fri Sep 25 02:29:30 2020 -0400
tree 9beb9d6952e798400f6444bae3a721c32446b34e
parent a6abf175ef310c3a5b6960b3c04ecac5feb4eb84

nir: gather information about fbfetch and dual source color

Reviewed-by: Eric Anholt <eric@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6758>

src/compiler/nir/nir_gather_info.c

diff --git a/src/compiler/nir/nir_gather_info.c b/src/compiler/nir/nir_gather_info.c
index 9547278..90320cb 100644
--- a/src/compiler/nir/nir_gather_info.c
+++ b/src/compiler/nir/nir_gather_info.c
@@ -151,8 +151,15 @@
          }
 
 
-         if (var->data.fb_fetch_output)
+         if (var->data.fb_fetch_output) {
             shader->info.outputs_read |= bitfield;
+            if (shader->info.stage == MESA_SHADER_FRAGMENT)
+               shader->info.fs.uses_fbfetch_output = true;
+         }
+
+         if (shader->info.stage == MESA_SHADER_FRAGMENT &&
+             !is_output_read && var->data.index == 1)
+            shader->info.fs.color_is_dual_source = true;
       }
    }
 }
@@ -402,6 +409,10 @@
           instr->intrinsic == nir_intrinsic_load_per_vertex_output &&
           !src_is_invocation_id(nir_get_io_vertex_index_src(instr)))
          shader->info.tess.tcs_cross_invocation_outputs_read |= slot_mask;
+
+      if (shader->info.stage == MESA_SHADER_FRAGMENT &&
+          nir_intrinsic_io_semantics(instr).fb_fetch_output)
+         shader->info.fs.uses_fbfetch_output = true;
       break;
 
    case nir_intrinsic_store_output:
@@ -416,6 +427,10 @@
          if (!nir_src_is_const(*nir_get_io_offset_src(instr)))
             shader->info.outputs_accessed_indirectly |= slot_mask;
       }
+
+      if (shader->info.stage == MESA_SHADER_FRAGMENT &&
+          nir_intrinsic_io_semantics(instr).dual_source_blend_index)
+         shader->info.fs.color_is_dual_source = true;
       break;
 
    case nir_intrinsic_load_subgroup_size:
@@ -777,6 +792,8 @@
       shader->info.fs.uses_sample_qualifier = false;
       shader->info.fs.uses_discard = false;
       shader->info.fs.uses_demote = false;
+      shader->info.fs.color_is_dual_source = false;
+      shader->info.fs.uses_fbfetch_output = false;
       shader->info.fs.needs_helper_invocations = false;
    }
    if (shader->info.stage == MESA_SHADER_TESS_CTRL) {

src/compiler/shader_info.h

diff --git a/src/compiler/shader_info.h b/src/compiler/shader_info.h
index eeb1cb0..23d174a 100644
--- a/src/compiler/shader_info.h
+++ b/src/compiler/shader_info.h
@@ -248,6 +248,8 @@
       struct {
          bool uses_discard:1;
          bool uses_demote:1;
+         bool uses_fbfetch_output:1;
+         bool color_is_dual_source:1;
 
          /**
           * True if this fragment shader requires helper invocations.  This