--- /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/SignExtendNode.java	2016-12-09 00:55:21.310828997 -0800
@@ -0,0 +1,113 @@
+/*
+ * 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.IntegerStamp;
+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 SignExtendNode} converts an integer to a wider integer using sign extension.
+ */
+@NodeInfo(cycles = CYCLES_1)
+public final class SignExtendNode extends IntegerConvertNode<SignExtend, Narrow> {
+
+    public static final NodeClass<SignExtendNode> TYPE = NodeClass.create(SignExtendNode.class);
+
+    public SignExtendNode(ValueNode input, int resultBits) {
+        this(input, PrimitiveStamp.getBits(input.stamp()), resultBits);
+        assert 0 < PrimitiveStamp.getBits(input.stamp()) && PrimitiveStamp.getBits(input.stamp()) <= resultBits;
+    }
+
+    public SignExtendNode(ValueNode input, int inputBits, int resultBits) {
+        super(TYPE, ArithmeticOpTable::getSignExtend, ArithmeticOpTable::getNarrow, 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<SignExtend> signExtend = ArithmeticOpTable.forStamp(input.stamp()).getSignExtend();
+        ValueNode synonym = findSynonym(signExtend, input, inputBits, resultBits, signExtend.foldStamp(inputBits, resultBits, input.stamp()));
+        if (synonym != null) {
+            return synonym;
+        } else {
+            return new SignExtendNode(input, inputBits, resultBits);
+        }
+    }
+
+    @Override
+    public boolean isLossless() {
+        return true;
+    }
+
+    @Override
+    public ValueNode canonical(CanonicalizerTool tool, ValueNode forValue) {
+        ValueNode ret = super.canonical(tool, forValue);
+        if (ret != this) {
+            return ret;
+        }
+
+        if (forValue instanceof SignExtendNode) {
+            // sxxx -(sign-extend)-> ssss sxxx -(sign-extend)-> ssssssss sssssxxx
+            // ==> sxxx -(sign-extend)-> ssssssss sssssxxx
+            SignExtendNode other = (SignExtendNode) forValue;
+            return new SignExtendNode(other.getValue(), other.getInputBits(), getResultBits());
+        } else if (forValue instanceof ZeroExtendNode) {
+            ZeroExtendNode other = (ZeroExtendNode) forValue;
+            if (other.getResultBits() > other.getInputBits()) {
+                // sxxx -(zero-extend)-> 0000 sxxx -(sign-extend)-> 00000000 0000sxxx
+                // ==> sxxx -(zero-extend)-> 00000000 0000sxxx
+                return new ZeroExtendNode(other.getValue(), other.getInputBits(), getResultBits());
+            }
+        }
+
+        if (forValue.stamp() instanceof IntegerStamp) {
+            IntegerStamp inputStamp = (IntegerStamp) forValue.stamp();
+            if ((inputStamp.upMask() & (1L << (getInputBits() - 1))) == 0L) {
+                // 0xxx -(sign-extend)-> 0000 0xxx
+                // ==> 0xxx -(zero-extend)-> 0000 0xxx
+                return new ZeroExtendNode(forValue, getInputBits(), getResultBits());
+            }
+        }
+
+        return this;
+    }
+
+    @Override
+    public void generate(NodeLIRBuilderTool nodeValueMap, ArithmeticLIRGeneratorTool gen) {
+        nodeValueMap.setResult(this, gen.emitSignExtend(nodeValueMap.operand(getValue()), getInputBits(), getResultBits()));
+    }
+}