--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.sl/src/com/oracle/truffle/sl/nodes/ReadFunctionNode.java	Mon Nov 11 21:34:44 2013 +0100
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.truffle.sl.nodes;
+
+import com.oracle.truffle.api.*;
+import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
+import com.oracle.truffle.api.frame.*;
+import com.oracle.truffle.sl.runtime.*;
+
+public final class ReadFunctionNode extends TypedNode {
+
+    private final SLFunctionRegistry registry;
+    private final String name;
+
+    @CompilationFinal private boolean seenInvalidFunction;
+
+    public ReadFunctionNode(SLFunctionRegistry registry, String name) {
+        this.registry = registry;
+        this.name = name;
+    }
+
+    @Override
+    public Object executeGeneric(VirtualFrame frame) {
+        return executeCallTarget(frame);
+    }
+
+    @Override
+    public CallTarget executeCallTarget(VirtualFrame frame) {
+        CallTarget target = registry.lookup(name);
+        if (target != null) {
+            return target;
+        }
+        if (!seenInvalidFunction) {
+            CompilerDirectives.transferToInterpreter();
+            seenInvalidFunction = true;
+        }
+        if (seenInvalidFunction) {
+            throw new RuntimeException("Function with name '" + name + "' not found.");
+        }
+        return null;
+    }
+
+}