VSI Fortran allows certain intrinsic functions for compatibility
  with FORTRAN for RISC.  The following list shows these functions
  and their equivalents:

     Function    Equivalent Function
     --------    -------------------
     AND         IAND
     OR          IOR
     XOR         IEOR
     LSHIFT      ISHFT with a positive second argument
     RSHIFT      ISHFT with a negative second argument