[OpenBIOS] Re: Paflof update

Segher Boessenkool segher at chello.nl
Sat Jan 2 04:46:30 CET 1904


> > > * implement unaligned-w@, unaligned-w!, unaligned-l@, unaligned-l!
> >
> > I'd rather have these implemented in Forth; we have too many primitives
> > already.
> 
> I don't agree on this. Unaligned accesses are slower than the aligned
> versions anyways, plus we need to bloat the forth code with endianess
> checks where we can solve this in the preprocessor in C. I made Forth

you actually don't need to know endianness to implement a fast unaligned-***
in pure Forth :)

: unaligned-l@   here /l move>  here l@  ;

etc.

> versions of these words as well, but while thinking about when you need
> unaligned accesses, I came to the conclusion that you probably don't
> want further slowdown. It's ugly that you have to break up atomicity of
> the access anyways.

most hardware won't allow general unaligned accesses to be atomic anyway...
i doubt we'll ever see unaligned-*** used on anything that's not just ram,
so there's no problem here.

> 
> > > * use conf.pl to create types.h according to compiler capabilities
> > >   (cross compiling possible) (cleaner version then last patch)
> >
> > I don't like it yet...
> 
> What's wrong?

it just "feels" ugly to me.

> > > * move unix host code from prim.code to unix.code
> >
> > Please leave it where it is, for now.  We'll move it when we compile
> > stuff from source (as opposed to the current situation: from a precompiled
> > dictionary).
> 
> Which reminds me that we also need support for multiple linked
> dictionaries when doing packages. Though maybe it might be enough to
> have multiple fcode lookup tables in the fcode evaluator?
> Is there any trivial way of doing this?

for the dictionaries, a little playing around with HERE and LAST and LATEST
will do.  fcode lookup tables are only valid for the package that
defines it,
and only during package loading, so i see no problem there?



Segher

-
To unsubscribe: send mail to majordomo at freiburg.linux.de
with 'unsubscribe openbios' in the body of the message
http://www.freiburg.linux.de/OpenBIOS/ - free your system..



More information about the openbios mailing list