--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/agent/src/share/classes/sun/jvm/hotspot/debugger/windows/x86/WindowsX86CFrame.java	Thu May 16 12:40:27 2013 +0100
@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2001, 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 sun.jvm.hotspot.debugger.windows.x86;
+
+import sun.jvm.hotspot.debugger.*;
+import sun.jvm.hotspot.debugger.x86.*;
+import sun.jvm.hotspot.debugger.cdbg.*;
+import sun.jvm.hotspot.debugger.cdbg.basic.*;
+import sun.jvm.hotspot.debugger.windbg.*;
+
+public class WindowsX86CFrame extends BasicCFrame {
+  private Address ebp;
+  private Address pc;
+
+  private static final int ADDRESS_SIZE = 4;
+
+  /** Constructor for topmost frame */
+  public WindowsX86CFrame(WindbgDebugger dbg, Address ebp, Address pc) {
+    super(dbg.getCDebugger());
+    this.ebp = ebp;
+    this.pc  = pc;
+    this.dbg = dbg;
+  }
+
+  public CFrame sender(ThreadProxy thread) {
+    X86ThreadContext context = (X86ThreadContext) thread.getContext();
+    Address esp = context.getRegisterAsAddress(X86ThreadContext.ESP);
+
+    if ( (ebp == null) || ebp.lessThan(esp) ) {
+      return null;
+    }
+
+    // Check alignment of ebp
+    if ( dbg.getAddressValue(ebp) % ADDRESS_SIZE != 0) {
+        return null;
+    }
+
+    Address nextEBP = ebp.getAddressAt( 0 * ADDRESS_SIZE);
+    if (nextEBP == null || nextEBP.lessThanOrEqual(ebp)) {
+      return null;
+    }
+    Address nextPC  = ebp.getAddressAt( 1 * ADDRESS_SIZE);
+    if (nextPC == null) {
+      return null;
+    }
+    return new WindowsX86CFrame(dbg, nextEBP, nextPC);
+  }
+
+  public Address pc() {
+    return pc;
+  }
+
+  public Address localVariableBase() {
+    return ebp;
+  }
+
+  private WindbgDebugger dbg;
+}