--- /dev/null	2016-05-31 09:42:47.975716356 -0700
+++ new/src/jdk.vm.compiler/share/classes/org.graalvm.compiler.core.test/src/org/graalvm/compiler/core/test/FindUniqueDefaultMethodTest.java	2016-12-09 00:47:33.856224173 -0800
@@ -0,0 +1,151 @@
+/*
+ * Copyright (c) 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 org.graalvm.compiler.core.test;
+
+import jdk.vm.ci.meta.Assumptions.AssumptionResult;
+import jdk.vm.ci.meta.ResolvedJavaMethod;
+import jdk.vm.ci.meta.ResolvedJavaType;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+import org.graalvm.compiler.debug.Debug;
+import org.graalvm.compiler.debug.Debug.Scope;
+import org.graalvm.compiler.nodes.ReturnNode;
+import org.graalvm.compiler.nodes.StructuredGraph;
+import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;
+
+/**
+ * This test illustrates problems and limitations with class hierarchy analysis when default methods
+ * are involved.
+ */
+public class FindUniqueDefaultMethodTest extends GraalCompilerTest {
+
+    interface Interface1 {
+        default int v1() {
+            return 1;
+        }
+    }
+
+    static class Implementor1 implements Interface1 {
+        int callV1() {
+            return v1();
+        }
+    }
+
+    static class Subclass1 extends Implementor1 {
+
+    }
+
+    /**
+     * HotSpot has an internal mismatch with CHA and default methods. The initial query says that
+     * it's a unique method but the verification code that ensures that a dependence of this kind
+     * would pass will fail an assert in debug mode.
+     */
+    @Test
+    public void testFindUnique() {
+        ResolvedJavaType cType = getMetaAccess().lookupJavaType(Implementor1.class);
+        cType.initialize();
+        ResolvedJavaMethod v1Method = getMetaAccess().lookupJavaMethod(this.getMethod(Interface1.class, "v1"));
+        AssumptionResult<ResolvedJavaMethod> method = cType.findUniqueConcreteMethod(v1Method);
+        assertDeepEquals(null, method);
+    }
+
+    interface Interface2 {
+        default int v1() {
+            return 1;
+        }
+    }
+
+    static class Base2 {
+        public int v2() {
+            return 1;
+        }
+    }
+
+    static class Implementor2 extends Base2 implements Interface2 {
+        int callV1() {
+            return v1();
+        }
+
+        int callV2() {
+            return v2();
+        }
+    }
+
+    static class Subclass2 extends Implementor2 {
+
+    }
+
+    /**
+     * This test illustrates a common pattern where a method at the root of a hierarchy is the only
+     * implementation and can be statically inlined.
+     */
+    @SuppressWarnings("unused")
+    @Test
+    public void testInherited() {
+        Subclass2 s = new Subclass2();
+        testConstantReturn("runInherited", 1);
+    }
+
+    /**
+     * Test same pattern as above but using default methods instead. HotSpot doesn't allow this
+     * version to be optimized.
+     */
+    @SuppressWarnings("unused")
+    @Test
+    @Ignore("HotSpot CHA doesn't treat default methods like regular methods")
+    public void testDefault() {
+        Subclass2 s = new Subclass2();
+        testConstantReturn("runDefault", 1);
+    }
+
+    public int runDefault(Implementor2 i) {
+        return i.callV1();
+    }
+
+    public int runInherited(Implementor2 i) {
+        return i.callV2();
+    }
+
+    private void testConstantReturn(String name, Object value) {
+        StructuredGraph result = buildGraph(name);
+        ReturnNode ret = result.getNodes(ReturnNode.TYPE).first();
+        assertDeepEquals(1, result.getNodes(ReturnNode.TYPE).count());
+
+        assertDeepEquals(true, ret.result().isConstant());
+        assertDeepEquals(value, ret.result().asJavaConstant().asBoxedPrimitive());
+    }
+
+    @SuppressWarnings("try")
+    protected StructuredGraph buildGraph(final String snippet) {
+        try (Scope s = Debug.scope("InstanceOfTest", getMetaAccess().lookupJavaMethod(getMethod(snippet)))) {
+            StructuredGraph graph = parseEager(snippet, AllowAssumptions.YES);
+            compile(graph.method(), graph);
+            Debug.dump(Debug.BASIC_LOG_LEVEL, graph, snippet);
+            return graph;
+        } catch (Throwable e) {
+            throw Debug.handle(e);
+        }
+    }
+}