[fpc-pascal] Common OpenMP syntax?

[Vinzent Hoefler]

On Wednesday 26 July 2006 10:05, Andreas Berger wrote:
> Steve Williams wrote:
> > Michael Van Canneyt wrote:
> >> Which is why I think that it's better to have them as local
> >> functions, instead of having to introduce a lot of new functions.
> >>
> >> Local functions are very pascal-ish. C doesn't have it, which is
> >> why they can't use it.
> >> Let's use the language features to their full extent.
> >
> >    *procedure* SubTask(*var* x : *array of* Float);
> >    *var*
> >      /// Variables declared here have /|*private*|/ context./
> >      iam     : Integer;
> >      nt      : Integer;
> >      ipoints : Integer;
> >    *parallel*
> >      iam := OMP.Get_Thread_Num;  /// OMP library calls./
> >      nt  := OMP.Get_Num_Threads;
> >             ipoints := Length (x) *div* nt; /// size of partition/
> >      istart  := iam * ipoints;     /// starting array index/
> >             *if* iam = Pred (nt) *then*
> >        ipoints := Length (x) - istart; /// last thread may do more/
> >             SubDomain (x, istart, ipoints);
> >    *end*;
>
> Wouldn't it be better to write it like this:
>     procedure SubTask(var x: array of Float); *parallel*;
>     var
>        ...
>     begin
>        ...
>     end;

Actually no. I thought about it, but I didn't get through all that stuff 
yesterday evening or else I would have updated the WiKi already. The 
problem I see is that the parallel directive has more meanings 
(basically it is the main directive). For that reason, I wouldn't want 
to put in on the callee, but rather on the caller.

I think it would also be easier for the compiler then to detect alls 
those parallel regions.

Let's see. Anyway, there was already more response I would have expected 
after the days of silence. :)


Vinzent.