Better way to recognize another way to express rotation?

[Jeffrey A Law]

  In message < 19991014124552.14309@atrey.karlin.mff.cuni.cz >you write:
  > Honza
  > Thu Oct 14 12:17:11 MET DST 1999  Jan Hubicka  <hubicka@freesoft.cz>
  > 	* combine.c (simplify_logical) Convert XOR to IOR if operands have
  > 	no bits in common; remove XOR to ROTATE conversion.
Thanks.  Installed.  
jeff