--- a/truffle/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/vm/EngineTest.java	Thu Nov 19 08:53:40 2015 +0100
+++ b/truffle/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/vm/EngineTest.java	Thu Nov 19 09:29:24 2015 +0100
@@ -24,8 +24,10 @@
 
 import com.oracle.truffle.api.source.Source;
 import com.oracle.truffle.api.vm.PolyglotEngine;
+import java.io.IOException;
 import java.util.List;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertNotNull;
 import org.junit.Test;
 
@@ -47,6 +49,39 @@
         assertNotNull(res);
     }
 
+    @Test
+    public void checkCachingOfNodes() throws IOException {
+        PolyglotEngine vm1 = createBuilder().build();
+        PolyglotEngine vm2 = createBuilder().build();
+
+        PolyglotEngine.Language language1 = vm1.getLanguages().get("application/x-test-hash");
+        PolyglotEngine.Language language2 = vm2.getLanguages().get("application/x-test-hash");
+        PolyglotEngine.Language alt1 = vm1.getLanguages().get("application/x-test-hash-alt");
+        PolyglotEngine.Language alt2 = vm2.getLanguages().get("application/x-test-hash-alt");
+        final Source sharedSource = Source.fromText("anything", "something");
+
+        Object hashIn1Round1 = language1.eval(sharedSource).get();
+        Object hashIn2Round1 = language2.eval(sharedSource).get();
+        Object hashIn1Round2 = language1.eval(sharedSource).get();
+        Object hashIn2Round2 = language2.eval(sharedSource).get();
+
+        Object altIn1Round1 = alt1.eval(sharedSource).get();
+        Object altIn2Round1 = alt2.eval(sharedSource).get();
+        Object altIn1Round2 = alt1.eval(sharedSource).get();
+        Object altIn2Round2 = alt2.eval(sharedSource).get();
+
+        assertEquals("Two executions in 1st engine share the nodes", hashIn1Round1, hashIn1Round2);
+        assertEquals("Two executions in 2nd engine share the nodes", hashIn2Round1, hashIn2Round2);
+
+        assertEquals("Two alternative executions in 1st engine share the nodes", altIn1Round1, altIn1Round2);
+        assertEquals("Two alternative executions in 2nd engine share the nodes", altIn2Round1, altIn2Round2);
+
+        assertNotEquals("Two executions in different languages don't share the nodes", hashIn1Round1, altIn1Round1);
+        assertNotEquals("Two executions in different languages don't share the nodes", hashIn1Round1, altIn2Round1);
+        assertNotEquals("Two executions in different languages don't share the nodes", hashIn2Round2, altIn1Round2);
+        assertNotEquals("Two executions in different languages don't share the nodes", hashIn2Round2, altIn2Round2);
+    }
+
     protected Thread forbiddenThread() {
         return null;
     }

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/truffle/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/vm/HashLanguage.java	Thu Nov 19 09:29:24 2015 +0100
@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 2015, 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.
+ *
+ * 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.test.vm;
+
+import com.oracle.truffle.api.CallTarget;
+import com.oracle.truffle.api.Truffle;
+import com.oracle.truffle.api.TruffleLanguage;
+import com.oracle.truffle.api.TruffleLanguage.Env;
+import com.oracle.truffle.api.frame.MaterializedFrame;
+import com.oracle.truffle.api.frame.VirtualFrame;
+import com.oracle.truffle.api.instrument.Visualizer;
+import com.oracle.truffle.api.instrument.WrapperNode;
+import com.oracle.truffle.api.nodes.Node;
+import com.oracle.truffle.api.nodes.RootNode;
+import com.oracle.truffle.api.source.Source;
+import java.io.IOException;
+
+@TruffleLanguage.Registration(name = "Hash", mimeType = "application/x-test-hash", version = "1.0")
+public class HashLanguage extends TruffleLanguage<Env> {
+    public static final HashLanguage INSTANCE = new HashLanguage();
+
+    @Override
+    protected Env createContext(Env env) {
+        return env;
+    }
+
+    @Override
+    protected CallTarget parse(Source code, Node context, String... argumentNames) throws IOException {
+        return Truffle.getRuntime().createCallTarget(new HashNode(this, code));
+    }
+
+    @Override
+    protected Object findExportedSymbol(Env context, String globalName, boolean onlyExplicit) {
+        return null;
+    }
+
+    @Override
+    protected Object getLanguageGlobal(Env context) {
+        return null;
+    }
+
+    @Override
+    protected boolean isObjectOfLanguage(Object object) {
+        return false;
+    }
+
+    @Override
+    protected Visualizer getVisualizer() {
+        return null;
+    }
+
+    @Override
+    protected boolean isInstrumentable(Node node) {
+        return false;
+    }
+
+    @Override
+    protected WrapperNode createWrapperNode(Node node) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    protected Object evalInContext(Source source, Node node, MaterializedFrame mFrame) throws IOException {
+        throw new UnsupportedOperationException("Not supported yet."); // To change body of
+                                                                       // generated methods, choose
+                                                                       // Tools | Templates.
+    }
+
+    private static class HashNode extends RootNode {
+        private static int counter;
+        private final Source code;
+        private final int id;
+
+        public HashNode(HashLanguage hash, Source code) {
+            super(hash.getClass(), null, null);
+            this.code = code;
+            id = ++counter;
+        }
+
+        @Override
+        public Object execute(VirtualFrame frame) {
+            return System.identityHashCode(this) + "@" + code.getCode() + " @ " + id;
+        }
+    }
+
+    @TruffleLanguage.Registration(name = "AltHash", mimeType = "application/x-test-hash-alt", version = "1.0")
+    public static final class SubLang extends HashLanguage {
+        public static final SubLang INSTANCE = new SubLang();
+    }
+}