--- /dev/null	2015-09-16 15:19:45.000000000 -0700
+++ new/src/java.base/share/classes/jdk.internal.jvmci.code/src/jdk/internal/jvmci/code/VirtualStackSlot.java	2015-09-16 15:19:45.000000000 -0700
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2014, 2014, 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 jdk.internal.jvmci.code;
+
+import jdk.internal.jvmci.meta.*;
+
+/**
+ * {@link VirtualStackSlot}s are stack slots that are not yet fixed to specific frame offset. They
+ * are replaced by real {@link StackSlot}s with a fixed position in the frame before code emission.
+ */
+public abstract class VirtualStackSlot extends StackSlotValue {
+
+    private final int id;
+
+    public VirtualStackSlot(int id, LIRKind lirKind) {
+        super(lirKind);
+        this.id = id;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    @Override
+    public String toString() {
+        return "vstack:" + id + getKindSuffix();
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = super.hashCode();
+        result = prime * result + id;
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (!super.equals(obj)) {
+            return false;
+        }
+        if (getClass() != obj.getClass()) {
+            return false;
+        }
+        VirtualStackSlot other = (VirtualStackSlot) obj;
+        if (id != other.id) {
+            return false;
+        }
+        return true;
+    }
+
+}