Re: [MiNT] Coldfire patches

[Peter Slegg <p.slegg@scubadivers.co.uk>]

On Sun, 31 Jul 2011 17:15:23 , Eero Tamminen <oak@helsinkinet.fi> wrote:
> Hi,
>
> On sunnuntai 31 heinäkuu 2011, Peter Slegg wrote:
> > This idea might be totally unworkable but it just occurred
> > to me so I thought I would share. It might be a non-issue.
> >
> > Self-extracting archives used to be used to squeeze apps onto a floppy.
> > Could a similar idea be used to create self-patching apps that run
> > on 680x0 and Coldfire ?
>
> Sounds cool and it could also do quick uncompression.  Disk speeds
> are still slower than CPU/RAM speeds and some compression/decompression
> algorithms like LZO are close to memcpy speed. :-)
>
>
> > I am mostly thinking about those op codes that can't be trapped.
> > The app would be wrapped in the patcher that knows which bits to
> > patch for Coldfire.
> >
> > When the app is launched, the wrapper checks the cpu and if it is
> > Coldfire, patches the app before running. For 680x0 it just runs.
>
> Is there anything needing patching which m68k & CF variants have differen
> t
> sizes (e.g. require different number of instructions)?  That would mess
> up offsets...
>
>
Yes I thought it would but I don't know the details of the patched codes.

Regards,

Peter