1 files changed, 104 insertions, 0 deletions
diff --git a/src/glsl/lower_vector_derefs.cpp b/src/glsl/lower_vector_derefs.cpp
new file mode 100644
index 0000000..4a5d6f0
--- /dev/null
+++ b/src/glsl/lower_vector_derefs.cpp
@@ -0,0 +1,104 @@
+/*
+ * Copyright © 2013 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 "ir.h"
+#include "ir_builder.h"
+#include "ir_rvalue_visitor.h"
+#include "ir_optimization.h"
+
+using namespace ir_builder;
+
+namespace {
+
+class vector_deref_visitor : public ir_rvalue_enter_visitor {
+public:
+   vector_deref_visitor()
+      : progress(false)
+   {
+   }
+
+   virtual ~vector_deref_visitor()
+   {
+   }
+
+   virtual void handle_rvalue(ir_rvalue **rv);
+   virtual ir_visitor_status visit_enter(ir_assignment *ir);
+
+   bool progress;
+};
+
+} /* anonymous namespace */
+
+ir_visitor_status
+vector_deref_visitor::visit_enter(ir_assignment *ir)
+{
+   if (!ir->lhs || ir->lhs->ir_type != ir_type_dereference_array)
+      return ir_rvalue_enter_visitor::visit_enter(ir);
+
+   ir_dereference_array *const deref = (ir_dereference_array *) ir->lhs;
+   if (!deref->array->type->is_vector())
+      return ir_rvalue_enter_visitor::visit_enter(ir);
+
+   ir_dereference *const new_lhs = (ir_dereference *) deref->array;
+   ir->set_lhs(new_lhs);
+
+   ir_constant *old_index_constant = deref->array_index->constant_expression_value();
+   void *mem_ctx = ralloc_parent(ir);
+   if (!old_index_constant) {
+      ir->rhs = new(mem_ctx) ir_expression(ir_triop_vector_insert,
+                                           new_lhs->type,
+                                           new_lhs->clone(mem_ctx, NULL),
+                                           ir->rhs,
+                                           deref->array_index);
+      ir->write_mask = (1 << new_lhs->type->vector_elements) - 1;
+   } else {
+      ir->write_mask = 1 << old_index_constant->get_int_component(0);
+   }
+
+   return ir_rvalue_enter_visitor::visit_enter(ir);
+}
+
+void
+vector_deref_visitor::handle_rvalue(ir_rvalue **rv)
+{
+   if (*rv == NULL || (*rv)->ir_type != ir_type_dereference_array)
+      return;
+
+   ir_dereference_array *const deref = (ir_dereference_array *) *rv;
+   if (!deref->array->type->is_vector())
+      return;
+
+   void *mem_ctx = ralloc_parent(deref);
+   *rv = new(mem_ctx) ir_expression(ir_binop_vector_extract,
+                                    deref->array,
+                                    deref->array_index);
+}
+
+bool
+lower_vector_derefs(gl_shader *shader)
+{
+   vector_deref_visitor v;
+
+   visit_list_elements(&v, shader->ir);
+
+   return v.progress;
+}