Add a constant folding optimization pass.

1 files changed, 131 insertions, 0 deletions

diff --git a/ir_constant_folding.cpp b/ir_constant_folding.cpp
new file mode 100644
index 00000000000..306f211fe56
--- /dev/null
+++ b/ir_constant_folding.cpp
@@ -0,0 +1,131 @@
+/*
+ * Copyright © 2010 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.
+ */
+
+/**
+ * \file ir_constant_folding.cpp
+ * Replace constant-valued expressions with references to constant values.
+ */
+
+#define NULL 0
+#include "ir.h"
+#include "ir_visitor.h"
+#include "ir_constant_folding.h"
+#include "glsl_types.h"
+
+/**
+ * Visitor class for replacing expressions with ir_constant values.
+ */
+
+void
+ir_constant_folding_visitor::visit(ir_variable *ir)
+{
+   (void) ir;
+}
+
+
+void
+ir_constant_folding_visitor::visit(ir_label *ir)
+{
+   (void) ir;
+}
+
+
+void
+ir_constant_folding_visitor::visit(ir_function_signature *ir)
+{
+   (void) ir;
+}
+
+
+void
+ir_constant_folding_visitor::visit(ir_function *ir)
+{
+   (void) ir;
+}
+
+void
+ir_constant_folding_visitor::visit(ir_expression *ir)
+{
+   ir_constant *op[2];
+   unsigned int operand;
+
+   for (operand = 0; operand < ir->get_num_operands(); operand++) {
+      op[operand] = ir->operands[operand]->constant_expression_value();
+      if (op[operand]) {
+	 ir->operands[operand] = op[operand];
+      }
+   }
+}
+
+
+void
+ir_constant_folding_visitor::visit(ir_swizzle *ir)
+{
+   (void) ir;
+}
+
+
+void
+ir_constant_folding_visitor::visit(ir_dereference *ir)
+{
+   (void) ir;
+}
+
+
+void
+ir_constant_folding_visitor::visit(ir_assignment *ir)
+{
+   ir_constant *const_val = ir->rhs->constant_expression_value();
+   if (const_val)
+      ir->rhs = const_val;
+   else
+      ir->rhs->accept(this);
+}
+
+
+void
+ir_constant_folding_visitor::visit(ir_constant *ir)
+{
+   (void) ir;
+}
+
+
+void
+ir_constant_folding_visitor::visit(ir_call *ir)
+{
+   (void) ir;
+}
+
+
+void
+ir_constant_folding_visitor::visit(ir_return *ir)
+{
+   (void) ir;
+}
+
+
+void
+ir_constant_folding_visitor::visit(ir_if *ir)
+{
+   (void) ir;
+}