--- /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/GuardEliminationCornerCasesTest.java	2016-12-09 00:47:35.731306800 -0800
@@ -0,0 +1,117 @@
+/*
+ * 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 org.graalvm.compiler.core.test;
+
+import org.junit.Test;
+
+import org.graalvm.compiler.api.directives.GraalDirectives;
+import org.graalvm.compiler.debug.Debug;
+import org.graalvm.compiler.graph.Node;
+import org.graalvm.compiler.nodes.AbstractBeginNode;
+import org.graalvm.compiler.nodes.BeginNode;
+import org.graalvm.compiler.nodes.FixedNode;
+import org.graalvm.compiler.nodes.GuardNode;
+import org.graalvm.compiler.nodes.LogicNode;
+import org.graalvm.compiler.nodes.StructuredGraph;
+import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;
+import org.graalvm.compiler.nodes.java.InstanceOfNode;
+import org.graalvm.compiler.nodes.spi.LoweringTool;
+import org.graalvm.compiler.nodes.spi.ValueProxy;
+import org.graalvm.compiler.phases.common.CanonicalizerPhase;
+import org.graalvm.compiler.phases.common.ConvertDeoptimizeToGuardPhase;
+import org.graalvm.compiler.phases.common.DominatorConditionalEliminationPhase;
+import org.graalvm.compiler.phases.common.LoweringPhase;
+import org.graalvm.compiler.phases.schedule.SchedulePhase;
+import org.graalvm.compiler.phases.tiers.HighTierContext;
+
+public class GuardEliminationCornerCasesTest extends GraalCompilerTest {
+
+    static class A {
+
+    }
+
+    static class B extends A {
+
+    }
+
+    static class C extends B {
+
+    }
+
+    static class D extends C {
+
+    }
+
+    @SuppressWarnings({"static-method", "unused"})
+    private int testMethod(Object a) {
+        if (a instanceof A) {
+            if (a instanceof C) {
+                if (a instanceof B) {
+                    B b = (B) a;
+                    if (b instanceof C) {
+                        return 1;
+                    } else {
+                        GraalDirectives.deoptimizeAndInvalidate();
+                    }
+                }
+            } else {
+                GraalDirectives.deoptimizeAndInvalidate();
+            }
+        }
+        return 0;
+    }
+
+    @Test
+    public void testFloatingGuards() {
+        HighTierContext context = getDefaultHighTierContext();
+        StructuredGraph graph = parseEager("testMethod", AllowAssumptions.YES);
+        new ConvertDeoptimizeToGuardPhase().apply(graph, context);
+        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();
+        new LoweringPhase(canonicalizer, LoweringTool.StandardLoweringStage.HIGH_TIER).apply(graph, context);
+        Debug.dump(Debug.BASIC_LOG_LEVEL, graph, "after parsing");
+
+        GuardNode myGuardNode = null;
+        for (Node n : graph.getNodes()) {
+            if (n instanceof GuardNode) {
+                GuardNode guardNode = (GuardNode) n;
+                LogicNode condition = guardNode.getCondition();
+                if (condition instanceof InstanceOfNode) {
+                    InstanceOfNode instanceOfNode = (InstanceOfNode) condition;
+                    if (instanceOfNode.getValue() instanceof ValueProxy) {
+                        myGuardNode = guardNode;
+                        break;
+                    }
+                }
+            }
+        }
+
+        AbstractBeginNode myBegin = (AbstractBeginNode) myGuardNode.getAnchor();
+        AbstractBeginNode prevBegin = BeginNode.prevBegin((FixedNode) myBegin.predecessor());
+        myGuardNode.setAnchor(prevBegin);
+
+        Debug.dump(Debug.BASIC_LOG_LEVEL, graph, "after manual modification");
+        graph.reverseUsageOrder();
+        new DominatorConditionalEliminationPhase(true).apply(graph, context);
+        new SchedulePhase(SchedulePhase.SchedulingStrategy.EARLIEST).apply(graph);
+    }
+}