--- /dev/null	2017-01-22 10:16:57.869617664 -0800
+++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.loop/src/org/graalvm/compiler/loop/InductionVariable.java	2017-02-15 17:06:09.426358664 -0800
@@ -0,0 +1,115 @@
+/*
+ * Copyright (c) 2012, 2012, 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.loop;
+
+import org.graalvm.compiler.core.common.type.Stamp;
+import org.graalvm.compiler.debug.GraalError;
+import org.graalvm.compiler.nodes.StructuredGraph;
+import org.graalvm.compiler.nodes.ValueNode;
+
+/**
+ * This class describes a value node that is an induction variable in a counted loop.
+ */
+public abstract class InductionVariable {
+
+    public enum Direction {
+        Up,
+        Down;
+
+        public Direction opposite() {
+            switch (this) {
+                case Up:
+                    return Down;
+                case Down:
+                    return Up;
+                default:
+                    throw GraalError.shouldNotReachHere();
+            }
+        }
+    }
+
+    public abstract StructuredGraph graph();
+
+    protected final LoopEx loop;
+
+    public InductionVariable(LoopEx loop) {
+        this.loop = loop;
+    }
+
+    public LoopEx getLoop() {
+        return loop;
+    }
+
+    public abstract Direction direction();
+
+    /**
+     * Returns the value node that is described by this induction variable.
+     */
+    public abstract ValueNode valueNode();
+
+    /**
+     * Returns the node that gives the initial value of this induction variable.
+     */
+    public abstract ValueNode initNode();
+
+    /**
+     * Returns the stride of the induction variable. The stride is the value that is added to the
+     * induction variable at each iteration.
+     */
+    public abstract ValueNode strideNode();
+
+    public abstract boolean isConstantInit();
+
+    public abstract boolean isConstantStride();
+
+    public abstract long constantInit();
+
+    public abstract long constantStride();
+
+    /**
+     * Returns the extremum value of the induction variable. The extremum value is the value of the
+     * induction variable in the loop body of the last iteration, only taking into account the main
+     * loop limit test. It's possible for the loop to exit before this value if
+     * {@link CountedLoopInfo#isExactTripCount()} returns false for the containing loop.
+     */
+    public ValueNode extremumNode() {
+        return extremumNode(false, valueNode().stamp());
+    }
+
+    public abstract ValueNode extremumNode(boolean assumePositiveTripCount, Stamp stamp);
+
+    public abstract boolean isConstantExtremum();
+
+    public abstract long constantExtremum();
+
+    /**
+     * Returns the exit value of the induction variable. The exit value is the value of the
+     * induction variable at the loop exit.
+     */
+    public abstract ValueNode exitValueNode();
+
+    /**
+     * Deletes any nodes created within the scope of this object that have no usages.
+     */
+    public abstract void deleteUnusedNodes();
+}