--- /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/NarrowNode.java	2016-12-09 00:55:18.108687851 -0800
@@ -0,0 +1,123 @@
+/*
+ * Copyright (c) 2014, 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 static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_1;
+
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable;
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable.IntegerConvertOp;
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable.IntegerConvertOp.Narrow;
+import org.graalvm.compiler.core.common.type.ArithmeticOpTable.IntegerConvertOp.SignExtend;
+import org.graalvm.compiler.core.common.type.PrimitiveStamp;
+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.ValueNode;
+import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool;
+
+/**
+ * The {@code NarrowNode} converts an integer to a narrower integer.
+ */
+@NodeInfo(cycles = CYCLES_1)
+public final class NarrowNode extends IntegerConvertNode<Narrow, SignExtend> {
+
+    public static final NodeClass<NarrowNode> TYPE = NodeClass.create(NarrowNode.class);
+
+    public NarrowNode(ValueNode input, int resultBits) {
+        this(input, PrimitiveStamp.getBits(input.stamp()), resultBits);
+        assert 0 < resultBits && resultBits <= PrimitiveStamp.getBits(input.stamp());
+    }
+
+    public NarrowNode(ValueNode input, int inputBits, int resultBits) {
+        super(TYPE, ArithmeticOpTable::getNarrow, ArithmeticOpTable::getSignExtend, inputBits, resultBits, input);
+    }
+
+    public static ValueNode create(ValueNode input, int resultBits) {
+        return create(input, PrimitiveStamp.getBits(input.stamp()), resultBits);
+    }
+
+    public static ValueNode create(ValueNode input, int inputBits, int resultBits) {
+        IntegerConvertOp<Narrow> signExtend = ArithmeticOpTable.forStamp(input.stamp()).getNarrow();
+        ValueNode synonym = findSynonym(signExtend, input, inputBits, resultBits, signExtend.foldStamp(inputBits, resultBits, input.stamp()));
+        if (synonym != null) {
+            return synonym;
+        } else {
+            return new NarrowNode(input, inputBits, resultBits);
+        }
+    }
+
+    @Override
+    public boolean isLossless() {
+        return false;
+    }
+
+    @Override
+    public ValueNode canonical(CanonicalizerTool tool, ValueNode forValue) {
+        ValueNode ret = super.canonical(tool, forValue);
+        if (ret != this) {
+            return ret;
+        }
+
+        if (forValue instanceof NarrowNode) {
+            // zzzzzzzz yyyyxxxx -(narrow)-> yyyyxxxx -(narrow)-> xxxx
+            // ==> zzzzzzzz yyyyxxxx -(narrow)-> xxxx
+            NarrowNode other = (NarrowNode) forValue;
+            return new NarrowNode(other.getValue(), other.getInputBits(), getResultBits());
+        } else if (forValue instanceof IntegerConvertNode) {
+            // SignExtendNode or ZeroExtendNode
+            IntegerConvertNode<?, ?> other = (IntegerConvertNode<?, ?>) forValue;
+            if (other.getValue().getUsageCount() == 1 && other.getUsageCount() > 1) {
+                // Do not perform if this will introduce a new live value.
+                // If the original value's usage count is > 1, there is already another user.
+                // If the convert's usage count is <=1, it will be dead code eliminated.
+                return this;
+            }
+            if (getResultBits() == other.getInputBits()) {
+                // xxxx -(extend)-> yyyy xxxx -(narrow)-> xxxx
+                // ==> no-op
+                return other.getValue();
+            } else if (getResultBits() < other.getInputBits()) {
+                // yyyyxxxx -(extend)-> zzzzzzzz yyyyxxxx -(narrow)-> xxxx
+                // ==> yyyyxxxx -(narrow)-> xxxx
+                return new NarrowNode(other.getValue(), other.getInputBits(), getResultBits());
+            } else {
+                if (other instanceof SignExtendNode) {
+                    // sxxx -(sign-extend)-> ssssssss sssssxxx -(narrow)-> sssssxxx
+                    // ==> sxxx -(sign-extend)-> sssssxxx
+                    return new SignExtendNode(other.getValue(), other.getInputBits(), getResultBits());
+                } else if (other instanceof ZeroExtendNode) {
+                    // xxxx -(zero-extend)-> 00000000 00000xxx -(narrow)-> 0000xxxx
+                    // ==> xxxx -(zero-extend)-> 0000xxxx
+                    return new ZeroExtendNode(other.getValue(), other.getInputBits(), getResultBits());
+                }
+            }
+        }
+        return this;
+    }
+
+    @Override
+    public void generate(NodeLIRBuilderTool nodeValueMap, ArithmeticLIRGeneratorTool gen) {
+        nodeValueMap.setResult(this, gen.emitNarrow(nodeValueMap.operand(getValue()), getResultBits()));
+    }
+}