[fpc-pascal]how much work is proting fpc

[Peter Vreman]

> Hi,
>
> At first: Don't get me wrong and expect anything, I'm only curious.
>
> That said:
> How much work would it be to port fpc to another processor?
> Same for another OS?
>
> Maybe some of the experienced folks can give a short sketch in a few
> sentences of the process of porting.

Porting fpc to another processor dependents on the processor. It is
difficult to give an exact idea. The sparc was started as third port, but
in the meanwhile the arm and amd64 are already finished. Things like
instructionset, alignment and calling conventions are the main parts of
the porting work. This is all using linux as the OS, since that includes
the less effort to port the RTL to another CPU.

To give a little indication of the time needed, porting the codegenerator
part will take about 2 months of work when you already know how the
compiler internals. This is only filling the already existing framework
and not needing any fundamental changes.

Example from the sparc is that it also needs fundamental changes to fix
alignment issues and support the calling conventions better. Then
everything takes a lot more time.


Porting fpc to another OS ask marco or olle. They did the last OS portings.