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Re: 16-bit real-mode code
> I ponder about writing a "i386 16bit realmode" gcc backend as my master
> thesis - which would be usefull for generating 16-bit bios code needed
> by the virtual machine developed at my university.
It's been done a couple of times already, first by me, and later my
code was extended by a couple of other people. Don't know if you want
to start from scratch "on principle" though, otherwise search the mail
archives.
> Having never programmed any compiler-related stuff and having a
> strict deadline (after 6 months) i would appreciate some commments
> about the complexity of such a venture.
It's not that bad, at least pointers are a reasonable size
(int-sized). IMHO the trick to setting up the registers is to assume
a bank of one-byte registers and use HARD_REGNO_NREGS to build up the
larger registers, rather than trying to use subregs to access parts of
larger registers. Arrange the registers such that DX:AX pairs are
adjacent too.