--- /dev/null	2016-05-31 09:42:47.975716356 -0700
+++ new/src/jdk.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/calc/RightShiftNode.java	2016-12-09 00:55:20.777805502 -0800
@@ -0,0 +1,120 @@
+/*
+ * Copyright (c) 2011, 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.nodes.calc;
+
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable;
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable.ShiftOp.Shr;
+import org.graalvm.compiler.core.common.type.IntegerStamp;
+import org.graalvm.compiler.graph.NodeClass;
+import org.graalvm.compiler.graph.spi.CanonicalizerTool;
+import org.graalvm.compiler.lir.gen.ArithmeticLIRGeneratorTool;
+import org.graalvm.compiler.nodeinfo.NodeInfo;
+import org.graalvm.compiler.nodes.ConstantNode;
+import org.graalvm.compiler.nodes.ValueNode;
+import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool;
+
+import jdk.vm.ci.code.CodeUtil;
+
+@NodeInfo(shortName = ">>")
+public final class RightShiftNode extends ShiftNode<Shr> {
+
+    public static final NodeClass<RightShiftNode> TYPE = NodeClass.create(RightShiftNode.class);
+
+    public RightShiftNode(ValueNode x, ValueNode y) {
+        super(TYPE, ArithmeticOpTable::getShr, x, y);
+    }
+
+    @Override
+    public ValueNode canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) {
+        ValueNode ret = super.canonical(tool, forX, forY);
+        if (ret != this) {
+            return ret;
+        }
+
+        if (forX.stamp() instanceof IntegerStamp && ((IntegerStamp) forX.stamp()).isPositive()) {
+            return new UnsignedRightShiftNode(forX, forY);
+        }
+
+        if (forY.isConstant()) {
+            int amount = forY.asJavaConstant().asInt();
+            int originalAmout = amount;
+            int mask = getShiftAmountMask();
+            amount &= mask;
+            if (amount == 0) {
+                return forX;
+            }
+            if (forX instanceof ShiftNode) {
+                ShiftNode<?> other = (ShiftNode<?>) forX;
+                if (other.getY().isConstant()) {
+                    int otherAmount = other.getY().asJavaConstant().asInt() & mask;
+                    if (other instanceof RightShiftNode) {
+                        int total = amount + otherAmount;
+                        if (total != (total & mask)) {
+                            assert other.getX().stamp() instanceof IntegerStamp;
+                            IntegerStamp istamp = (IntegerStamp) other.getX().stamp();
+
+                            if (istamp.isPositive()) {
+                                return ConstantNode.forIntegerKind(getStackKind(), 0);
+                            }
+                            if (istamp.isStrictlyNegative()) {
+                                return ConstantNode.forIntegerKind(getStackKind(), -1L);
+                            }
+
+                            /*
+                             * if we cannot replace both shifts with a constant, replace them by a
+                             * full shift for this kind
+                             */
+                            assert total >= mask;
+                            return new RightShiftNode(other.getX(), ConstantNode.forInt(mask));
+                        }
+                        return new RightShiftNode(other.getX(), ConstantNode.forInt(total));
+                    }
+                }
+            }
+            if (originalAmout != amount) {
+                return new RightShiftNode(forX, ConstantNode.forInt(amount));
+            }
+        }
+        return this;
+    }
+
+    @Override
+    public void generate(NodeLIRBuilderTool nodeValueMap, ArithmeticLIRGeneratorTool gen) {
+        nodeValueMap.setResult(this, gen.emitShr(nodeValueMap.operand(getX()), nodeValueMap.operand(getY())));
+    }
+
+    @Override
+    public boolean isNarrowable(int resultBits) {
+        if (super.isNarrowable(resultBits)) {
+            /*
+             * For signed right shifts, the narrow can be done before the shift if the cut off bits
+             * are all equal to the sign bit of the input. That's equivalent to the condition that
+             * the input is in the signed range of the narrow type.
+             */
+            IntegerStamp inputStamp = (IntegerStamp) getX().stamp();
+            return CodeUtil.minValue(resultBits) <= inputStamp.lowerBound() && inputStamp.upperBound() <= CodeUtil.maxValue(resultBits);
+        } else {
+            return false;
+        }
+    }
+}