[GSoC] the AMD64 port

[Sascha Wildner]

Matthew Dillon wrote:
:I'm a student interested in doing the AMD64 port as a Google Summer of 
:Code project.
:I would like to have some questions answered, in order to be able to 
:make an informed decision.
:  1. Does porting require messing with the source code of gcc/binutils/gdb?

    This might need a little work.  64 bit world builds will generate
    a 64 bit cross compiler which the 64 bit kernel build should use (when
    building on a 32 bit platform), but currently our libraries in /usr/lib
    use a single path for 32 or 64 bit libs so we can't build a compiler that
    supports both.
    This means you should be able to work on a 64 bit kernel without messing
    with the compiler sources, though we might need to do a few small
    cleanups.
    I think it would be beneficial for our 2.0 release to actually go through
    the pain of moving our 32 bit libraries into a i386 or amd64 subdirectory,
    with the original directory turned into a softlink, or something like
    that so we would be able to have both targets on the same architecture.
    That's probably a mini-project in of itself.
I may be repeating myself :), but I feel I should mention that Noah Yan 
(the guy who did the pc64/amd64 stuff we have already in base) has 
~330KB of uncommitted stuff lying in his git repo at 
http://repo.or.cz/w/dragonfly/port-amd64.git. It would be a pity if this 
work would be repeated again.

I've put the patch also here: 
http://leaf.dragonflybsd.org/~swildner/64_yanyh.diff

I was thinking about just committing it so others can pick up, although 
pc64 world is again broken with this stuff in and I also am not 100% 
sure if it generally makes things better or worse.

Have fun,
Sascha
--
http://yoyodyne.ath.cx