Re: Implementing OpenMP pragmas for the C front end

[Geoff Keating <geoffk at geoffk dot org>]

Neil Booth <neil@daikokuya.co.uk> writes:

> David Edelsohn wrote:-
> 
> > 	Unfortunately, this is a public standard.  Somehow we need to be
> > compatible. 
> > 
> > 	What we really want is some way of converting
> > 
> > #pragma omp flush (x)
> > 
> > to
> > 
> > __builtin_omp_flush (x);
> > 
> > which is a more natural way of implementing this and would allow semantic
> > error checking.
> 
> On second thoughts it's possibly not as bad as I thought.  I had in mind
> that the #pragma callbacks would be conditional on parser state; of
> course that needn't be the implementation.  The callbacks should happen
> regardless, and the front end should ignore/reject appropriately.

All you really want is a way for the #pragma callback to respond with
"please pass #pragma to the parser as a token"; then the parser can
handle it.

[Mind, I'm a bit worried about what this might make the parser look
like; maybe we would really prefer to use another preprocessor before
the code actually gets to the compiler, not try to handle the pragmas
in the compiler itself.]

-- 
- Geoffrey Keating <geoffk@geoffk.org>