as supports the following names for registers:
general register 0general register 1general register 2general register 3general register 4general register 5general register 6general register 7general register 8general register 9general register 10general register 11general register 12general register 13general register 14general register 15general register 16general register 17general register 18general register 19general register 20general register 21general register 22general register 23general register 24general register 25general register 26general register 27general register 28general register 29general register 30general register 31system register 0system register 1system register 2system register 3system register 4system register 5system register 16system register 17system register 18system register 19system register 20