[Mesa-dev] [PATCH 2/4] glsl: store uniform slot id in var location field

[Timothy Arceri]

This will allow us to access the uniform later on without resorting to
building a name string and looking it up in UniformHash.
---
 src/glsl/ir.h              |  2 ++
 src/glsl/link_uniforms.cpp | 21 ++++++++++++++++++---
 src/glsl/nir/nir.h         |  2 ++
 3 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/src/glsl/ir.h b/src/glsl/ir.h
index ede8caa..9bcaf28 100644
--- a/src/glsl/ir.h
+++ b/src/glsl/ir.h
@@ -819,6 +819,8 @@ public:
        *   - Fragment shader output: one of the values from \c gl_frag_result.
        *   - Uniforms: Per-stage uniform slot number for default uniform block.
        *   - Uniforms: Index within the uniform block definition for UBO members.
+       *   - Opaque Uniforms: explicit binding until linking then reused to
+       *     store uniform slot number.
        *   - Other: This field is not currently used.
        *
        * If the variable is a uniform, shader input, or shader output, and the
diff --git a/src/glsl/link_uniforms.cpp b/src/glsl/link_uniforms.cpp
index 8bf5ef9..c28f13d 100644
--- a/src/glsl/link_uniforms.cpp
+++ b/src/glsl/link_uniforms.cpp
@@ -458,6 +458,7 @@ public:
    {
       current_var = var;
       field_counter = 0;
+      this->explicit_binding = current_var->data.location;
       this->record_next_sampler = new string_to_uint_map;
 
       ubo_block_index = -1;
@@ -510,12 +511,18 @@ public:
                     var->get_interface_type()->name);
          else
             process(var);
-      } else
+      } else {
+         /* Reset data location so we can reuse this variable for storing the
+          * uniform slot of opaque types.
+          */
+         current_var->data.location = -1;
+
          process(var);
       }
       delete this->record_next_sampler;
    }
 
+
    int ubo_block_index;
    int ubo_byte_offset;
    gl_shader_stage shader_type;
@@ -697,16 +704,23 @@ private:
          return;
       }
 
+      /* For array of arrays or struct arrays the base location may have
+       * already been set so dont set it again.
+       */
+      if (base_type->contains_opaque() && current_var->data.location == -1) {
+          current_var->data.location = id;
+      }
+
       /* Assign explicit locations. */
       if (current_var->data.explicit_location) {
          /* Set sequential locations for struct fields. */
          if (record_type != NULL) {
             const unsigned entries = MAX2(1, this->uniforms[id].array_elements);
             this->uniforms[id].remap_location =
-               current_var->data.location + field_counter;
+               this->explicit_binding + field_counter;
             field_counter += entries;
          } else {
-            this->uniforms[id].remap_location = current_var->data.location;
+            this->uniforms[id].remap_location = this->explicit_binding;
          }
       } else {
          /* Initialize to to indicate that no location is set */
@@ -771,6 +785,7 @@ private:
    unsigned next_sampler;
    unsigned next_image;
    unsigned next_subroutine;
+   int explicit_binding;
 
    /* Stores total struct array elements including nested structs */
    unsigned sampler_count;
diff --git a/src/glsl/nir/nir.h b/src/glsl/nir/nir.h
index 9703372..a051af1 100644
--- a/src/glsl/nir/nir.h
+++ b/src/glsl/nir/nir.h
@@ -278,6 +278,8 @@ typedef struct {
        *   - Fragment shader output: one of the values from \c gl_frag_result.
        *   - Uniforms: Per-stage uniform slot number for default uniform block.
        *   - Uniforms: Index within the uniform block definition for UBO members.
+       *   - Opaque Uniforms: explicit binding until linking then reused to
+       *     store uniform slot number.
        *   - Other: This field is not currently used.
        *
        * If the variable is a uniform, shader input, or shader output, and the
-- 
2.4.3