[Mesa-dev] [PATCH v2 04/17] main, glsl: Add UniformDataDefaults which stores uniform defaults

[Jordan Justen]

The ARB_get_program_binary extension requires that uniform values in a
program be restored to their initial value just after linking.

This patch saves off the initial values just after linking. When the
program is restored by glProgramBinary, we can use this to copy the
initial value of uniforms into UniformDataSlots.

Signed-off-by: Jordan Justen <jordan.l.justen at intel.com>
Reviewed-by: Timothy Arceri <tarceri at itsqueeze.com>
---
 src/compiler/glsl/link_uniform_initializers.cpp |  2 ++
 src/compiler/glsl/link_uniforms.cpp             |  3 +++
 src/compiler/glsl/serialize.cpp                 | 18 ++++++++++++++++--
 src/mesa/main/mtypes.h                          | 11 +++++++++++
 4 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/src/compiler/glsl/link_uniform_initializers.cpp b/src/compiler/glsl/link_uniform_initializers.cpp
index f70d9100e12..2395f5cf695 100644
--- a/src/compiler/glsl/link_uniform_initializers.cpp
+++ b/src/compiler/glsl/link_uniform_initializers.cpp
@@ -354,5 +354,7 @@ link_set_uniform_initializers(struct gl_shader_program *prog,
       }
    }
 
+   memcpy(prog->data->UniformDataDefaults, prog->data->UniformDataSlots,
+          sizeof(union gl_constant_value) * prog->data->NumUniformDataSlots);
    ralloc_free(mem_ctx);
 }
diff --git a/src/compiler/glsl/link_uniforms.cpp b/src/compiler/glsl/link_uniforms.cpp
index 46c746bc701..15813cb0aed 100644
--- a/src/compiler/glsl/link_uniforms.cpp
+++ b/src/compiler/glsl/link_uniforms.cpp
@@ -1365,6 +1365,9 @@ link_assign_uniform_storage(struct gl_context *ctx,
                                                  prog->data->NumUniformStorage);
       data = rzalloc_array(prog->data->UniformStorage,
                            union gl_constant_value, num_data_slots);
+      prog->data->UniformDataDefaults =
+         rzalloc_array(prog->data->UniformStorage,
+                       union gl_constant_value, num_data_slots);
    } else {
       data = prog->data->UniformDataSlots;
    }
diff --git a/src/compiler/glsl/serialize.cpp b/src/compiler/glsl/serialize.cpp
index 81781f32dfd..c907ef0ad80 100644
--- a/src/compiler/glsl/serialize.cpp
+++ b/src/compiler/glsl/serialize.cpp
@@ -449,7 +449,12 @@ write_uniforms(struct blob *metadata, struct gl_shader_program *prog)
          unsigned vec_size =
             prog->data->UniformStorage[i].type->component_slots() *
             MAX2(prog->data->UniformStorage[i].array_elements, 1);
-         blob_write_bytes(metadata, prog->data->UniformStorage[i].storage,
+         unsigned slot =
+            prog->data->UniformStorage[i].storage -
+            prog->data->UniformDataSlots;
+         blob_write_bytes(metadata, &prog->data->UniformDataSlots[slot],
+                          sizeof(union gl_constant_value) * vec_size);
+         blob_write_bytes(metadata, &prog->data->UniformDataDefaults[slot],
                           sizeof(union gl_constant_value) * vec_size);
       }
    }
@@ -472,6 +477,9 @@ read_uniforms(struct blob_reader *metadata, struct gl_shader_program *prog)
    data = rzalloc_array(uniforms, union gl_constant_value,
                         prog->data->NumUniformDataSlots);
    prog->data->UniformDataSlots = data;
+   prog->data->UniformDataDefaults =
+      rzalloc_array(uniforms, union gl_constant_value,
+                    prog->data->NumUniformDataSlots);
 
    prog->UniformHash = new string_to_uint_map;
 
@@ -512,8 +520,14 @@ read_uniforms(struct blob_reader *metadata, struct gl_shader_program *prog)
          unsigned vec_size =
             prog->data->UniformStorage[i].type->component_slots() *
             MAX2(prog->data->UniformStorage[i].array_elements, 1);
+         unsigned slot =
+            prog->data->UniformStorage[i].storage -
+            prog->data->UniformDataSlots;
+         blob_copy_bytes(metadata,
+                         (uint8_t *) &prog->data->UniformDataSlots[slot],
+                         sizeof(union gl_constant_value) * vec_size);
          blob_copy_bytes(metadata,
-                         (uint8_t *) prog->data->UniformStorage[i].storage,
+                         (uint8_t *) &prog->data->UniformDataDefaults[slot],
                          sizeof(union gl_constant_value) * vec_size);
 
         assert(vec_size + prog->data->UniformStorage[i].storage <=
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 4682e02fc85..e305f6b577b 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -2877,6 +2877,17 @@ struct gl_shader_program_data
    unsigned NumUniformDataSlots;
    union gl_constant_value *UniformDataSlots;
 
+   /* Used to hold initial uniform values for program binary restores.
+    *
+    * From the ARB_get_program_binary spec:
+    *
+    *    "A successful call to ProgramBinary will reset all uniform
+    *    variables to their initial values. The initial value is either
+    *    the value of the variable's initializer as specified in the
+    *    original shader source, or 0 if no initializer was present.
+    */
+   union gl_constant_value *UniformDataDefaults;
+
    /* TODO: This used by Gallium drivers to skip the cache on tgsi fallback.
     * All structures (gl_program, uniform storage, etc) will get recreated
     * even though we have already loaded them from cache. We should instead
-- 
2.14.1