[Mesa-dev] [PATCH v2 10/12] nir/st_glsl_to_nir: add param to disable splitting of inputs

[Timothy Arceri]

We need this because we will always copy fs outputs to temps and
split the arrays, but do not want to do either of these with fs
inputs as it is unnessisary and makes handling interpolateAt
builtins difficult.
---
 src/compiler/nir/nir.h                             |  3 ++-
 src/compiler/nir/nir_lower_io_arrays_to_elements.c | 22 +++++++++++++---------
 src/mesa/state_tracker/st_glsl_to_nir.cpp          |  2 +-
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h
index 4bb96c3c95..86d1c68fa7 100644
--- a/src/compiler/nir/nir.h
+++ b/src/compiler/nir/nir.h
@@ -2522,7 +2522,8 @@ bool nir_lower_load_const_to_scalar(nir_shader *shader);
 bool nir_lower_read_invocation_to_scalar(nir_shader *shader);
 bool nir_lower_phis_to_scalar(nir_shader *shader);
 void nir_lower_io_arrays_to_elements(nir_shader *producer, nir_shader *consumer);
-void nir_lower_io_arrays_to_elements_no_indirects(nir_shader *shader);
+void nir_lower_io_arrays_to_elements_no_indirects(nir_shader *shader,
+                                                  bool outputs_only);
 void nir_lower_io_to_scalar(nir_shader *shader, nir_variable_mode mask);
 void nir_lower_io_to_scalar_early(nir_shader *shader, nir_variable_mode mask);
 
diff --git a/src/compiler/nir/nir_lower_io_arrays_to_elements.c b/src/compiler/nir/nir_lower_io_arrays_to_elements.c
index cdf9a76a88..9a5eec8f87 100644
--- a/src/compiler/nir/nir_lower_io_arrays_to_elements.c
+++ b/src/compiler/nir/nir_lower_io_arrays_to_elements.c
@@ -346,7 +346,8 @@ lower_io_arrays_to_elements(nir_shader *shader, nir_variable_mode mask,
 }
 
 void
-nir_lower_io_arrays_to_elements_no_indirects(nir_shader *shader)
+nir_lower_io_arrays_to_elements_no_indirects(nir_shader *shader,
+                                             bool outputs_only)
 {
    struct hash_table *split_inputs =
       _mesa_hash_table_create(NULL, _mesa_hash_pointer,
@@ -360,19 +361,22 @@ nir_lower_io_arrays_to_elements_no_indirects(nir_shader *shader)
    lower_io_arrays_to_elements(shader, nir_var_shader_out, indirects,
                                patch_indirects, split_outputs, true);
 
-   lower_io_arrays_to_elements(shader, nir_var_shader_in, indirects,
-                               patch_indirects, split_inputs, true);
+   if (!outputs_only) {
+      lower_io_arrays_to_elements(shader, nir_var_shader_in, indirects,
+                                  patch_indirects, split_inputs, true);
 
-   /* Remove old input from the shaders inputs list */
-   struct hash_entry *entry;
-   hash_table_foreach(split_inputs, entry) {
-      nir_variable *var = (nir_variable *) entry->key;
-      exec_node_remove(&var->node);
+      /* Remove old input from the shaders inputs list */
+      struct hash_entry *entry;
+      hash_table_foreach(split_inputs, entry) {
+         nir_variable *var = (nir_variable *) entry->key;
+         exec_node_remove(&var->node);
 
-      free(entry->data);
+         free(entry->data);
+      }
    }
 
    /* Remove old output from the shaders outputs list */
+   struct hash_entry *entry;
    hash_table_foreach(split_outputs, entry) {
       nir_variable *var = (nir_variable *) entry->key;
       exec_node_remove(&var->node);
diff --git a/src/mesa/state_tracker/st_glsl_to_nir.cpp b/src/mesa/state_tracker/st_glsl_to_nir.cpp
index 6d3a7c78dc..a3d447c5a4 100644
--- a/src/mesa/state_tracker/st_glsl_to_nir.cpp
+++ b/src/mesa/state_tracker/st_glsl_to_nir.cpp
@@ -660,7 +660,7 @@ st_finalize_nir(struct st_context *st, struct gl_program *prog,
    NIR_PASS_V(nir, nir_lower_var_copies);
    if (nir->info.stage != MESA_SHADER_TESS_CTRL &&
        nir->info.stage != MESA_SHADER_TESS_EVAL)
-      NIR_PASS_V(nir, nir_lower_io_arrays_to_elements_no_indirects);
+      NIR_PASS_V(nir, nir_lower_io_arrays_to_elements_no_indirects, false);
 
    if (nir->info.stage == MESA_SHADER_VERTEX) {
       /* Needs special handling so drvloc matches the vbo state: */
-- 
2.14.3