--- /dev/null	2017-01-22 10:16:57.869617664 -0800
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.core.test/src/org/graalvm/compiler/core/test/UnsafeReadEliminationTest.java	2017-02-15 16:57:50.310600291 -0800
@@ -0,0 +1,145 @@
+/*
+ * Copyright (c) 2016, 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 java.lang.reflect.Field;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import org.graalvm.compiler.api.directives.GraalDirectives;
+import org.graalvm.compiler.nodes.StructuredGraph;
+import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;
+import org.graalvm.compiler.nodes.extended.UnsafeAccessNode;
+import org.graalvm.compiler.nodes.memory.ReadNode;
+import org.graalvm.compiler.nodes.memory.WriteNode;
+import org.graalvm.compiler.nodes.spi.LoweringTool;
+import org.graalvm.compiler.phases.common.CanonicalizerPhase;
+import org.graalvm.compiler.phases.common.LoweringPhase;
+import org.graalvm.compiler.phases.tiers.PhaseContext;
+import org.graalvm.compiler.virtual.phases.ea.EarlyReadEliminationPhase;
+import org.graalvm.compiler.virtual.phases.ea.PartialEscapePhase;
+
+import sun.misc.Unsafe;
+
+public class UnsafeReadEliminationTest extends GraalCompilerTest {
+
+    public static final Unsafe UNSAFE;
+    static {
+        try {
+            Field theUnsafe = Unsafe.class.getDeclaredField("theUnsafe");
+            theUnsafe.setAccessible(true);
+            UNSAFE = (Unsafe) theUnsafe.get(Unsafe.class);
+        } catch (Exception e) {
+            throw new RuntimeException("Exception while trying to get Unsafe", e);
+        }
+    }
+
+    public static long[] Memory = new long[]{1, 2};
+    public static double SideEffectD;
+    public static double SideEffectL;
+
+    public static long test1Snippet(double a) {
+        final Object m = Memory;
+        if (a > 0) {
+            UNSAFE.putDouble(m, (long) Unsafe.ARRAY_LONG_BASE_OFFSET, a);
+        } else {
+            SideEffectL = UNSAFE.getLong(m, (long) Unsafe.ARRAY_LONG_BASE_OFFSET);
+        }
+        return UNSAFE.getLong(m, (long) Unsafe.ARRAY_LONG_BASE_OFFSET);
+    }
+
+    public static class A {
+        long[][] o;
+        long[][] p;
+    }
+
+    public static Object test2Snippet(A a, int c) {
+        Object phi = null;
+        if (c != 0) {
+            long[][] r = a.o;
+            phi = r;
+            UNSAFE.putDouble(r, (long) Unsafe.ARRAY_LONG_BASE_OFFSET, 12d);
+        } else {
+            long[][] r = a.p;
+            phi = r;
+            UNSAFE.putLong(r, (long) Unsafe.ARRAY_LONG_BASE_OFFSET, 123);
+        }
+        GraalDirectives.controlFlowAnchor();
+        SideEffectD = UNSAFE.getDouble(phi, (long) Unsafe.ARRAY_LONG_BASE_OFFSET);
+        return phi;
+    }
+
+    @Test
+    public void test01() {
+        StructuredGraph graph = parseEager("test1Snippet", AllowAssumptions.NO);
+        testEarlyReadElimination(graph, 3, 2);
+    }
+
+    @Test
+    public void test02() {
+        StructuredGraph graph = parseEager("test1Snippet", AllowAssumptions.NO);
+        testPartialEscapeReadElimination(graph, 3, 2);
+    }
+
+    @Test
+    public void test03() {
+        StructuredGraph graph = parseEager("test2Snippet", AllowAssumptions.NO);
+        testEarlyReadElimination(graph, 3, 3);
+    }
+
+    @Test
+    public void test04() {
+        StructuredGraph graph = parseEager("test2Snippet", AllowAssumptions.NO);
+        testEarlyReadElimination(graph, 3, 3);
+    }
+
+    public void testEarlyReadElimination(StructuredGraph graph, int reads, int writes) {
+        PhaseContext context = getDefaultHighTierContext();
+        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();
+        canonicalizer.apply(graph, context);
+        new EarlyReadEliminationPhase(canonicalizer).apply(graph, context);
+        Assert.assertEquals(3, graph.getNodes().filter(UnsafeAccessNode.class).count());
+        // after lowering the same applies for reads and writes
+        new LoweringPhase(canonicalizer, LoweringTool.StandardLoweringStage.HIGH_TIER).apply(graph, context);
+        canonicalizer.apply(graph, context);
+        new EarlyReadEliminationPhase(canonicalizer).apply(graph, context);
+        Assert.assertEquals(reads, graph.getNodes().filter(ReadNode.class).count());
+        Assert.assertEquals(writes, graph.getNodes().filter(WriteNode.class).count());
+    }
+
+    public void testPartialEscapeReadElimination(StructuredGraph graph, int reads, int writes) {
+        PhaseContext context = getDefaultHighTierContext();
+        CanonicalizerPhase canonicalizer = new CanonicalizerPhase();
+        canonicalizer.apply(graph, context);
+        new PartialEscapePhase(true, true, canonicalizer, null).apply(graph, context);
+        Assert.assertEquals(3, graph.getNodes().filter(UnsafeAccessNode.class).count());
+        // after lowering the same applies for reads and writes
+        new LoweringPhase(canonicalizer, LoweringTool.StandardLoweringStage.HIGH_TIER).apply(graph, context);
+        canonicalizer.apply(graph, context);
+        new PartialEscapePhase(true, true, canonicalizer, null).apply(graph, context);
+        Assert.assertEquals(reads, graph.getNodes().filter(ReadNode.class).count());
+        Assert.assertEquals(writes, graph.getNodes().filter(WriteNode.class).count());
+    }
+
+}