The VM needs to be changed to support the new features of JSR-166.  While most of
the changes are in the library, the following VM changes are needed:
 * Support for new methods in sun.misc.Unsafe for volatile field access.
  * Support for new methods in sun.misc.Unsafe to provide atomic compare-and-swap operations
  * Suport for a new method java.lang.System.nanoTime() for high-resolution timing
  * Changes to both Compiler1 and Compiler2 to handle the new methods as intrinsics.
  * Changes to improve the memory barriers generated for volatile memory accesses.