Re: RFC: Merge the GUPC branch into the GCC 6.0 trunk

[Bernd Schmidt <bschmidt at redhat dot com>]

On 12/01/2015 06:31 AM, Gary Funck wrote:
> At this time, we would like to re-submit the UPC patches for comment
> with the goal of introducing these changes into GCC 6.0.

This has missed stage 1 by a few weeks, we'd have to make an exception 
to include it at this late stage.

> @@ -857,9 +875,14 @@ struct GTY(()) tree_base {
>         unsigned user_align : 1;
>         unsigned nameless_flag : 1;
>         unsigned atomic_flag : 1;
> -      unsigned spare0 : 3;
> -
> -      unsigned spare1 : 8;
> +      unsigned shared_flag : 1;
> +      unsigned strict_flag : 1;
> +      unsigned relaxed_flag : 1;
> +
> +      unsigned threads_factor_flag : 1;
> +      unsigned block_factor_0 : 1;
> +      unsigned block_factor_x : 1;
> +      unsigned spare1 : 5;

That's a lot of bits used up at once.

Does this solve anything that cannot be done with OpenMP, which we 
already support? Can you show us any users of this that demonstrate that 
this is actually in use by anyone outside the universities responsible 
for UPC? The language standard is apparently from 2005, but I've never 
heard of it and googling "upc" does not give any sensible results. The 
gccupc mailing list seems to have been dead for years judging by the 
archives. I'm worried we'll end up carrying something around as a burden 
that is of no practical use (considering we already support the more 
widespread OpenMP).


Bernd