--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.sl/src/com/oracle/truffle/sl/SLTypes.java	Fri Jan 18 13:29:14 2013 +0100
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2012, 2012, 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;
+
+import java.math.*;
+
+import com.oracle.truffle.api.codegen.*;
+
+@TypeSystem({int.class, BigInteger.class, boolean.class, String.class})
+public class SLTypes {
+
+    @TypeCheck
+    public boolean isInteger(Object value) {
+        return value instanceof Integer || (value instanceof BigInteger && ((BigInteger) value).bitLength() < Integer.SIZE);
+    }
+
+    @TypeCast
+    public int asInteger(Object value) {
+        assert isInteger(value);
+        if (value instanceof Integer) {
+            return (int) value;
+        } else {
+            int result = ((BigInteger) value).intValue();
+            assert BigInteger.valueOf(result).equals(value) : "Loosing precision";
+            return result;
+        }
+    }
+
+    @TypeCheck
+    public boolean isBigInteger(Object value) {
+        return value instanceof Integer || value instanceof BigInteger;
+    }
+
+    @TypeCast
+    public BigInteger asBigInteger(Object value) {
+        if (value instanceof Integer) {
+            return BigInteger.valueOf((int) value);
+        } else {
+            return (BigInteger) value;
+        }
+    }
+
+    @TypeCast
+    public BigInteger asBigInteger(int value) {
+        return BigInteger.valueOf(value);
+    }
+
+    @TypeCheck
+    public boolean isBigInteger(@SuppressWarnings("unused") int value) {
+        return true;
+    }
+}
+