--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/runtime/basicLock.cpp	Fri Oct 22 15:59:34 2010 -0400
@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 1997, 2010, 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.
+ *
+ */
+
+# include "incls/_precompiled.incl"
+# include "incls/_basicLock.cpp.incl"
+
+void BasicLock::print_on(outputStream* st) const {
+  st->print("monitor");
+}
+
+void BasicLock::move_to(oop obj, BasicLock* dest) {
+  // Check to see if we need to inflate the lock. This is only needed
+  // if an object is locked using "this" lightweight monitor. In that
+  // case, the displaced_header() is unlocked, because the
+  // displaced_header() contains the header for the originally unlocked
+  // object. However the object could have already been inflated. But it
+  // does not matter, the inflation will just a no-op. For other cases,
+  // the displaced header will be either 0x0 or 0x3, which are location
+  // independent, therefore the BasicLock is free to move.
+  //
+  // During OSR we may need to relocate a BasicLock (which contains a
+  // displaced word) from a location in an interpreter frame to a
+  // new location in a compiled frame.  "this" refers to the source
+  // basiclock in the interpreter frame.  "dest" refers to the destination
+  // basiclock in the new compiled frame.  We *always* inflate in move_to().
+  // The always-Inflate policy works properly, but in 1.5.0 it can sometimes
+  // cause performance problems in code that makes heavy use of a small # of
+  // uncontended locks.   (We'd inflate during OSR, and then sync performance
+  // would subsequently plummet because the thread would be forced thru the slow-path).
+  // This problem has been made largely moot on IA32 by inlining the inflated fast-path
+  // operations in Fast_Lock and Fast_Unlock in i486.ad.
+  //
+  // Note that there is a way to safely swing the object's markword from
+  // one stack location to another.  This avoids inflation.  Obviously,
+  // we need to ensure that both locations refer to the current thread's stack.
+  // There are some subtle concurrency issues, however, and since the benefit is
+  // is small (given the support for inflated fast-path locking in the fast_lock, etc)
+  // we'll leave that optimization for another time.
+
+  if (displaced_header()->is_neutral()) {
+    ObjectSynchronizer::inflate_helper(obj);
+    // WARNING: We can not put check here, because the inflation
+    // will not update the displaced header. Once BasicLock is inflated,
+    // no one should ever look at its content.
+  } else {
+    // Typically the displaced header will be 0 (recursive stack lock) or
+    // unused_mark.  Naively we'd like to assert that the displaced mark
+    // value is either 0, neutral, or 3.  But with the advent of the
+    // store-before-CAS avoidance in fast_lock/compiler_lock_object
+    // we can find any flavor mark in the displaced mark.
+  }
+// [RGV] The next line appears to do nothing!
+  intptr_t dh = (intptr_t) displaced_header();
+  dest->set_displaced_header(displaced_header());
+}