glsl: Set initial values for uniforms in the linker

v2: Fix handling of arrays-of-structure.  Thanks to Eric Anholt for
pointing this out.

v3: Minor comment change based on feedback from Ken.

Fixes piglit glsl-1.20/execution/uniform-initializer/fs-structure-array
and glsl-1.20/execution/uniform-initializer/vs-structure-array.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

4 files changed, 178 insertions, 0 deletions

diff --git a/src/glsl/Makefile.sources b/src/glsl/Makefile.sources
index fba03604cc5d..caa8ad590c04 100644
--- a/src/glsl/Makefile.sources
+++ b/src/glsl/Makefile.sources
@@ -46,6 +46,7 @@ LIBGLSL_CXX_FILES := \
 	linker.cpp \
 	link_functions.cpp \
 	link_uniforms.cpp \
+	link_uniform_initializers.cpp \
 	loop_analysis.cpp \
 	loop_controls.cpp \
 	loop_unroll.cpp \
diff --git a/src/glsl/link_uniform_initializers.cpp b/src/glsl/link_uniform_initializers.cpp
new file mode 100644
index 000000000000..46f05261f187
--- /dev/null
+++ b/src/glsl/link_uniform_initializers.cpp
@@ -0,0 +1,172 @@
+/*
+ * Copyright © 2012 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include "main/core.h"
+#include "ir.h"
+#include "linker.h"
+#include "ir_uniform.h"
+#include "glsl_symbol_table.h"
+#include "program/hash_table.h"
+
+/* These functions are put in a "private" namespace instead of being marked
+ * static so that the unit tests can access them.  See
+ * http://code.google.com/p/googletest/wiki/AdvancedGuide#Testing_Private_Code
+ */
+namespace linker {
+
+gl_uniform_storage *
+get_storage(gl_uniform_storage *storage, unsigned num_storage,
+	    const char *name)
+{
+   for (unsigned int i = 0; i < num_storage; i++) {
+      if (strcmp(name, storage[i].name) == 0)
+	 return &storage[i];
+   }
+
+   return NULL;
+}
+
+void
+copy_constant_to_storage(union gl_constant_value *storage,
+			 const ir_constant *val,
+			 const enum glsl_base_type base_type,
+			 const unsigned int elements)
+{
+   for (unsigned int i = 0; i < elements; i++) {
+      switch (base_type) {
+      case GLSL_TYPE_UINT:
+	 storage[i].u = val->value.u[i];
+	 break;
+      case GLSL_TYPE_INT:
+      case GLSL_TYPE_SAMPLER:
+	 storage[i].i = val->value.i[i];
+	 break;
+      case GLSL_TYPE_FLOAT:
+	 storage[i].f = val->value.f[i];
+	 break;
+      case GLSL_TYPE_BOOL:
+	 storage[i].b = int(val->value.b[i]);
+	 break;
+      default:
+	 /* All other types should have already been filtered by other
+	  * paths in the caller.
+	  */
+	 assert(!"Should not get here.");
+	 break;
+      }
+   }
+}
+
+void
+set_uniform_initializer(void *mem_ctx, gl_shader_program *prog,
+			const char *name, const glsl_type *type,
+			ir_constant *val)
+{
+   if (type->is_record()) {
+      ir_constant *field_constant;
+
+      field_constant = (ir_constant *)val->components.get_head();
+
+      for (unsigned int i = 0; i < type->length; i++) {
+	 const glsl_type *field_type = type->fields.structure[i].type;
+	 const char *field_name = ralloc_asprintf(mem_ctx, "%s.%s", name,
+					    type->fields.structure[i].name);
+	 set_uniform_initializer(mem_ctx, prog, field_name,
+				 field_type, field_constant);
+	 field_constant = (ir_constant *)field_constant->next;
+      }
+      return;
+   } else if (type->is_array() && type->fields.array->is_record()) {
+      const glsl_type *const element_type = type->fields.array;
+
+      for (unsigned int i = 0; i < type->length; i++) {
+	 const char *element_name = ralloc_asprintf(mem_ctx, "%s[%d]", name, i);
+
+	 set_uniform_initializer(mem_ctx, prog, element_name,
+				 element_type, val->array_elements[i]);
+      }
+      return;
+   }
+
+   struct gl_uniform_storage *const storage =
+      get_storage(prog->UniformStorage,
+		  prog->NumUserUniformStorage,
+		  name);
+   if (storage == NULL) {
+      assert(storage != NULL);
+      return;
+   }
+
+   if (val->type->is_array()) {
+      const enum glsl_base_type base_type =
+	 val->array_elements[0]->type->base_type;
+      const unsigned int elements = val->array_elements[0]->type->components();
+      unsigned int idx = 0;
+
+      assert(val->type->length >= storage->array_elements);
+      for (unsigned int i = 0; i < storage->array_elements; i++) {
+	 copy_constant_to_storage(& storage->storage[idx],
+				  val->array_elements[i],
+				  base_type,
+				  elements);
+
+	 idx += elements;
+      }
+   } else {
+      copy_constant_to_storage(storage->storage,
+			       val,
+			       val->type->base_type,
+			       val->type->components());
+   }
+
+   storage->initialized = true;
+}
+}
+
+void
+link_set_uniform_initializers(struct gl_shader_program *prog)
+{
+   void *mem_ctx = NULL;
+
+   for (unsigned int i = 0; i < MESA_SHADER_TYPES; i++) {
+      struct gl_shader *shader = prog->_LinkedShaders[i];
+
+      if (shader == NULL)
+	 continue;
+
+      foreach_list(node, shader->ir) {
+	 ir_variable *const var = ((ir_instruction *) node)->as_variable();
+
+	 if (!var || var->mode != ir_var_uniform || !var->constant_value)
+	    continue;
+
+	 if (!mem_ctx)
+	    mem_ctx = ralloc_context(NULL);
+
+	 linker::set_uniform_initializer(mem_ctx, prog, var->name,
+					 var->type, var->constant_value);
+      }
+   }
+
+   ralloc_free(mem_ctx);
+}
diff --git a/src/glsl/link_uniforms.cpp b/src/glsl/link_uniforms.cpp
index 2f1c9f5f70ff..81a995e92bda 100644
--- a/src/glsl/link_uniforms.cpp
+++ b/src/glsl/link_uniforms.cpp
@@ -426,5 +426,7 @@ link_assign_uniform_locations(struct gl_shader_program *prog)
    prog->NumUserUniformStorage = num_user_uniforms;
    prog->UniformStorage = uniforms;
 
+   link_set_uniform_initializers(prog);
+
    return;
 }
diff --git a/src/glsl/linker.h b/src/glsl/linker.h
index 0b4c001f7e3a..d0aaf3e1e7d2 100644
--- a/src/glsl/linker.h
+++ b/src/glsl/linker.h
@@ -37,6 +37,9 @@ link_invalidate_variable_locations(gl_shader *sh, enum ir_variable_mode mode,
 extern void
 link_assign_uniform_locations(struct gl_shader_program *prog);
 
+extern void
+link_set_uniform_initializers(struct gl_shader_program *prog);
+
 /**
  * Class for processing all of the leaf fields of an uniform
  *