- Added regsOverlap() to test if two registers overlap. Or in case they are   virtual registers, test if they the same. - Added a virtual method to return target specific reserved registers, e.g. SP.
- Added regsOverlap() to test if two registers overlap. Or in case they are
  virtual registers, test if they the same.
- Added a virtual method to return target specific reserved registers, e.g. SP.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@34375 91177308-0d34-0410-b5e6-96231b3b80d8

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