They work with the 16-bit registers BC, DE and HL, returning the
corresponding 8-bit register. HIGH() works with AF as well, returning A.
They also work with any kind of constant or symbol, generating a RPN
patch in the object file if the value is not defined at assembly time.
They work with macro arguments as well.
Signed-off-by: Antonio Niño Díaz <antonio_nd@outlook.com>
Merging lai's source with this one is very irritating because
they have different indentation styles. I couldn't find what profile
vegard used for his version, so I used these flags (which should bring
the source close to KNF):
-bap
-br
-ce
-ci4
-cli0
-d0
-di0
-i8
-ip
-l79
-nbc
-ncdb
-ndj
-ei
-nfc1
-nlp
-npcs
-psl
-sc
-sob
