Re: A85: Rigel, where'd it go??


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Re: A85: Rigel, where'd it go??



Sam Davies wrote:
> 
> Ben Sferrazza wrote:
> 
> > Michael Pearce wrote:
> > >
> > > And don't forget that program sizes are smaller in Rigel than they are
> > > in Usgard.
> > >
> > > -mike pearce
> > >
> > > BTW, does it take 2 additional bytes for every "&" you stick in a
> > > Usgard program to put in the relocation table?
> >
> > Sure.  Since Usgard uses some sort of fixup table for all relocation,
> > you must have at least two bytes for every fixup.  Ah, the beauty of
> > fixed address relocation.
> 
> Actually, no!  It takes in most cases only *1* byte to store the address!
> How can we do this, you ask?  We store addresses relatively -- that is we
> store the offset from the last relocation address.  So if there are two &'s
> within 256 bytes, it will only take one byte :)
>     Sam
> 
> --
> Sam Davies <sdavies@mail.trilogy.net>

Hm, how can you tell if the next 2 relocations are relative or if the
next relocation is absolute? Do the absolutes take 3 bytes?

-- 
Terry Peng <tpeng@geocities.com>


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