diff -r 4ebc2e2fb97c -r 71c04702a3d5 src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/runtime/PerfDataPrologue.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/runtime/PerfDataPrologue.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2004, 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 sun.jvm.hotspot.runtime;
+
+import java.util.*;
+import sun.jvm.hotspot.debugger.*;
+import sun.jvm.hotspot.oops.*;
+import sun.jvm.hotspot.types.*;
+
+public class PerfDataPrologue extends VMObject {
+    private static JIntField  magicField;
+    private static JByteField byteOrderField;
+    private static JByteField majorVersionField;
+    private static JByteField minorVersionField;
+    private static JByteField accessibleField;
+    private static JIntField  usedField;
+    private static JIntField  overflowField;
+    private static JLongField modTimeStampField;
+    private static JIntField  entryOffsetField;
+    private static JIntField  numEntriesField;
+
+    static {
+        VM.registerVMInitializedObserver(new Observer() {
+                public void update(Observable o, Object data) {
+                    initialize(VM.getVM().getTypeDataBase());
+                }
+            });
+    }
+
+    private static synchronized void initialize(TypeDataBase db) {
+        Type type = db.lookupType("PerfDataPrologue");
+        magicField = type.getJIntField("magic");
+        byteOrderField = type.getJByteField("byte_order");
+        majorVersionField = type.getJByteField("major_version");
+        minorVersionField = type.getJByteField("minor_version");
+        accessibleField = type.getJByteField("accessible");
+        usedField = type.getJIntField("used");
+        overflowField = type.getJIntField("overflow");
+        modTimeStampField = type.getJLongField("mod_time_stamp");
+        entryOffsetField = type.getJIntField("entry_offset");
+        numEntriesField = type.getJIntField("num_entries");
+    }
+
+    public PerfDataPrologue(Address addr) {
+        super(addr);
+    }
+
+    // Accessors
+    public int magic() {
+        return (int) magicField.getValue(addr);
+    }
+
+    public byte byteOrder() {
+        return (byte) byteOrderField.getValue(addr);
+    }
+
+    public byte majorVersion() {
+        return (byte) majorVersionField.getValue(addr);
+    }
+
+    public boolean accessible() {
+        return ((byte) accessibleField.getValue(addr)) != (byte)0;
+    }
+
+    public int used() {
+        return (int) usedField.getValue(addr);
+    }
+
+    public int overflow() {
+        return (int) overflowField.getValue(addr);
+    }
+
+    public long modTimeStamp() {
+        return (long) modTimeStampField.getValue(addr);
+    }
+
+    public int entryOffset() {
+        return (int) entryOffsetField.getValue(addr);
+    }
+
+    public int numEntries() {
+        return (int) numEntriesField.getValue(addr);
+    }
+}