--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api.interop/src/com/oracle/truffle/api/interop/impl/SymbolInvokerImpl.java	Mon Jun 08 04:50:13 2015 +0200
@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 2014, 2015, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.api.interop.impl;
+
+import java.io.*;
+
+import com.oracle.truffle.api.*;
+import com.oracle.truffle.api.frame.*;
+import com.oracle.truffle.api.impl.*;
+import com.oracle.truffle.api.interop.ForeignAccess;
+import com.oracle.truffle.api.interop.Message;
+import com.oracle.truffle.api.interop.TruffleObject;
+import com.oracle.truffle.api.nodes.*;
+
+public final class SymbolInvokerImpl extends SymbolInvoker {
+    static final FrameDescriptor UNUSED_FRAMEDESCRIPTOR = new FrameDescriptor();
+
+    @Override
+    protected Object invoke(Object symbol, Object... arr) throws IOException {
+        if (symbol instanceof String) {
+            return symbol;
+        }
+        if (symbol instanceof Number) {
+            return symbol;
+        }
+        if (symbol instanceof Boolean) {
+            return symbol;
+        }
+        Node executeMain = Message.createExecute(arr.length).createNode();
+        CallTarget callTarget = Truffle.getRuntime().createCallTarget(new TemporaryRoot(executeMain, (TruffleObject) symbol, arr));
+        VirtualFrame frame = Truffle.getRuntime().createVirtualFrame(arr, UNUSED_FRAMEDESCRIPTOR);
+        Object ret = callTarget.call(frame);
+        if (ret instanceof TruffleObject) {
+            TruffleObject tret = (TruffleObject) ret;
+            Object isBoxedResult;
+            try {
+                Node isBoxed = Message.IS_BOXED.createNode();
+                CallTarget isBoxedTarget = Truffle.getRuntime().createCallTarget(new TemporaryRoot(isBoxed, tret));
+                isBoxedResult = isBoxedTarget.call(frame);
+            } catch (IllegalArgumentException ex) {
+                isBoxedResult = false;
+            }
+            if (Boolean.TRUE.equals(isBoxedResult)) {
+                Node unbox = Message.UNBOX.createNode();
+                CallTarget unboxTarget = Truffle.getRuntime().createCallTarget(new TemporaryRoot(unbox, tret));
+                Object unboxResult = unboxTarget.call(frame);
+                return unboxResult;
+            } else {
+                try {
+                    Node isNull = Message.IS_NULL.createNode();
+                    CallTarget isNullTarget = Truffle.getRuntime().createCallTarget(new TemporaryRoot(isNull, tret));
+                    Object isNullResult = isNullTarget.call(frame);
+                    if (Boolean.TRUE.equals(isNullResult)) {
+                        return null;
+                    }
+                } catch (IllegalArgumentException ex) {
+                    // fallthrough
+                }
+            }
+        }
+        return ret;
+    }
+
+    private static class TemporaryRoot extends RootNode {
+        @Child private Node foreignAccess;
+        private final TruffleObject function;
+        private final Object[] args;
+
+        public TemporaryRoot(Node foreignAccess, TruffleObject function, Object... args) {
+            this.foreignAccess = foreignAccess;
+            this.function = function;
+            this.args = args;
+        }
+
+        @Override
+        public Object execute(VirtualFrame frame) {
+            return ForeignAccess.execute(foreignAccess, frame, function, args);
+        }
+    }
+
+}