--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.sl/src/com/oracle/truffle/sl/nodes/instrument/SLExpressionWrapperNode.java	Sun Nov 23 16:07:23 2014 -0800
@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2012, 2014, 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.instrument;
+
+import java.math.*;
+
+import com.oracle.truffle.api.frame.*;
+import com.oracle.truffle.api.instrument.*;
+import com.oracle.truffle.api.instrument.ProbeNode.WrapperNode;
+import com.oracle.truffle.api.nodes.*;
+import com.oracle.truffle.sl.nodes.*;
+import com.oracle.truffle.sl.runtime.*;
+
+/**
+ * A Truffle node that can be inserted into a Simple AST (assumed not to have executed yet) to
+ * enable "instrumentation" of an {@link SLExpressionNode}. Tools wishing to interact with AST
+ * execution may attach {@link Instrument}s to the {@link Probe} uniquely associated with the
+ * wrapper, and to which this wrapper routes execution events.
+ */
+@NodeInfo(cost = NodeCost.NONE)
+public final class SLExpressionWrapperNode extends SLExpressionNode implements WrapperNode {
+    @Child private SLExpressionNode child;
+    @Child private ProbeNode probeNode;
+
+    /**
+     * Constructor.
+     *
+     * @param child The {@link SLExpressionNode} that this wrapper is wrapping
+     */
+    public SLExpressionWrapperNode(SLExpressionNode child) {
+        super(child.getSourceSection());
+        assert !(child instanceof SLExpressionWrapperNode);
+        this.child = child;
+    }
+
+    public String instrumentationInfo() {
+        return "Wrapper node for SL Expressions";
+    }
+
+    @Override
+    public SLExpressionNode getNonWrapperNode() {
+        return child;
+    }
+
+    public void insertProbe(ProbeNode newProbeNode) {
+        this.probeNode = newProbeNode;
+    }
+
+    public Probe getProbe() {
+        try {
+            return probeNode.getProbe();
+        } catch (IllegalStateException e) {
+            throw new IllegalStateException("A lite-Probed wrapper has no explicit Probe");
+        }
+    }
+
+    public Node getChild() {
+        return child;
+    }
+
+    @Override
+    public Object executeGeneric(VirtualFrame frame) {
+
+        probeNode.enter(child, frame);
+        Object result;
+
+        try {
+            result = child.executeGeneric(frame);
+            probeNode.returnValue(child, frame, result);
+        } catch (Exception e) {
+            probeNode.returnExceptional(child, frame, e);
+            throw (e);
+        }
+        return result;
+    }
+
+    @Override
+    public long executeLong(VirtualFrame frame) throws UnexpectedResultException {
+        return SLTypesGen.SLTYPES.expectLong(executeGeneric(frame));
+    }
+
+    @Override
+    public BigInteger executeBigInteger(VirtualFrame frame) throws UnexpectedResultException {
+        return SLTypesGen.SLTYPES.expectBigInteger(executeGeneric(frame));
+    }
+
+    @Override
+    public boolean executeBoolean(VirtualFrame frame) throws UnexpectedResultException {
+        return SLTypesGen.SLTYPES.expectBoolean(executeGeneric(frame));
+    }
+
+    @Override
+    public String executeString(VirtualFrame frame) throws UnexpectedResultException {
+        return SLTypesGen.SLTYPES.expectString(executeGeneric(frame));
+    }
+
+    @Override
+    public SLFunction executeFunction(VirtualFrame frame) throws UnexpectedResultException {
+        probeNode.enter(child, frame);
+        SLFunction result;
+
+        try {
+            result = child.executeFunction(frame);
+            probeNode.returnValue(child, frame, result);
+        } catch (Exception e) {
+            probeNode.returnExceptional(child, frame, e);
+            throw (e);
+        }
+        return result;
+    }
+
+    @Override
+    public SLNull executeNull(VirtualFrame frame) throws UnexpectedResultException {
+        return SLTypesGen.SLTYPES.expectSLNull(executeGeneric(frame));
+    }
+
+    @Override
+    public Probe probe() {
+        throw new IllegalStateException("Cannot call probe() on a wrapper.");
+    }
+
+    @Override
+    public void probeLite(TruffleEventReceiver eventReceiver) {
+        throw new IllegalStateException("Cannot call probeLite() on a wrapper.");
+    }
+}