(ARC_MACH_MASK, ARC_OPCODE_MACH, ARC_OPVAL_MACH): Define. (ARC_HAVE_MULT_SHIFT): Delete. (ARC_HAVE_MACH): Define. (struct arc_opcode): New field `flags'. (struct arc_operand_value): Ditto. (arc_opcode_supported): New function. (arc_opval_supported): Ditto.