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diff --git a/src/glsl/ir_expression_flattening.cpp b/src/glsl/ir_expression_flattening.cpp
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+++ b/src/glsl/ir_expression_flattening.cpp
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+/*
+ * 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_expression_flattening.cpp
+ *
+ * Takes the leaves of expression trees and makes them dereferences of
+ * assignments of the leaves to temporaries, according to a predicate.
+ *
+ * This is used for automatic function inlining, where we want to take
+ * an expression containing a call and move the call out to its own
+ * assignment so that we can inline it at the appropriate place in the
+ * instruction stream.
+ */
+
+#include "ir.h"
+#include "ir_visitor.h"
+#include "ir_expression_flattening.h"
+#include "glsl_types.h"
+
+class ir_expression_flattening_visitor : public ir_hierarchical_visitor {
+public:
+   ir_expression_flattening_visitor(ir_instruction *base_ir,
+				    bool (*predicate)(ir_instruction *ir))
+   {
+      this->base_ir = base_ir;
+      this->predicate = predicate;
+   }
+
+   virtual ~ir_expression_flattening_visitor()
+   {
+      /* empty */
+   }
+
+   virtual ir_visitor_status visit_enter(ir_call *);
+   virtual ir_visitor_status visit_enter(ir_return *);
+   virtual ir_visitor_status visit_enter(ir_function_signature *);
+   virtual ir_visitor_status visit_enter(ir_if *);
+   virtual ir_visitor_status visit_enter(ir_loop *);
+   virtual ir_visitor_status visit_leave(ir_assignment *);
+   virtual ir_visitor_status visit_leave(ir_expression *);
+   virtual ir_visitor_status visit_leave(ir_swizzle *);
+
+   ir_rvalue *operand_to_temp(ir_rvalue *val);
+   bool (*predicate)(ir_instruction *ir);
+   ir_instruction *base_ir;
+};
+
+void
+do_expression_flattening(exec_list *instructions,
+			 bool (*predicate)(ir_instruction *ir))
+{
+   foreach_iter(exec_list_iterator, iter, *instructions) {
+      ir_instruction *ir = (ir_instruction *)iter.get();
+
+      ir_expression_flattening_visitor v(ir, predicate);
+      ir->accept(&v);
+   }
+}
+
+
+ir_rvalue *
+ir_expression_flattening_visitor::operand_to_temp(ir_rvalue *ir)
+{
+   void *ctx = base_ir;
+   ir_variable *var;
+   ir_assignment *assign;
+
+   if (!this->predicate(ir))
+      return ir;
+
+   var = new(ctx) ir_variable(ir->type, "flattening_tmp", ir_var_temporary);
+   base_ir->insert_before(var);
+
+   assign = new(ctx) ir_assignment(new(ctx) ir_dereference_variable(var),
+				   ir,
+				   NULL);
+   base_ir->insert_before(assign);
+
+   return new(ctx) ir_dereference_variable(var);
+}
+
+ir_visitor_status
+ir_expression_flattening_visitor::visit_enter(ir_function_signature *ir)
+{
+   do_expression_flattening(&ir->body, this->predicate);
+
+   return visit_continue_with_parent;
+}
+
+ir_visitor_status
+ir_expression_flattening_visitor::visit_enter(ir_loop *ir)
+{
+   do_expression_flattening(&ir->body_instructions, this->predicate);
+
+   return visit_continue_with_parent;
+}
+
+ir_visitor_status
+ir_expression_flattening_visitor::visit_enter(ir_if *ir)
+{
+   ir->condition->accept(this);
+
+   do_expression_flattening(&ir->then_instructions, this->predicate);
+   do_expression_flattening(&ir->else_instructions, this->predicate);
+
+   return visit_continue_with_parent;
+}
+
+ir_visitor_status
+ir_expression_flattening_visitor::visit_leave(ir_expression *ir)
+{
+   unsigned int operand;
+
+   for (operand = 0; operand < ir->get_num_operands(); operand++) {
+      /* If the operand matches the predicate, then we'll assign its
+       * value to a temporary and deref the temporary as the operand.
+       */
+      ir->operands[operand] = operand_to_temp(ir->operands[operand]);
+   }
+
+   return visit_continue;
+}
+
+ir_visitor_status
+ir_expression_flattening_visitor::visit_leave(ir_assignment *ir)
+{
+   ir->rhs = operand_to_temp(ir->rhs);
+   if (ir->condition)
+      ir->condition = operand_to_temp(ir->condition);
+
+   return visit_continue;
+}
+
+ir_visitor_status
+ir_expression_flattening_visitor::visit_leave(ir_swizzle *ir)
+{
+   if (this->predicate(ir->val)) {
+      ir->val = operand_to_temp(ir->val);
+   }
+
+   return visit_continue;
+}
+
+ir_visitor_status
+ir_expression_flattening_visitor::visit_enter(ir_call *ir)
+{
+   /* Reminder: iterating ir_call iterates its parameters. */
+   foreach_iter(exec_list_iterator, iter, *ir) {
+      ir_rvalue *ir = (ir_rvalue *)iter.get();
+      ir_rvalue *new_ir = operand_to_temp(ir);
+
+      if (new_ir != ir) {
+	 ir->replace_with(new_ir);
+      }
+   }
+
+   return visit_continue;
+}
+
+
+ir_visitor_status
+ir_expression_flattening_visitor::visit_enter(ir_return *ir)
+{
+   if (ir->value)
+      ir->value = operand_to_temp(ir->value);
+   return visit_continue;
+}