Re: [PATCH] Handle BUILT_IN_GOACC_PARALLEL in ipa-pta

[Thomas Schwinge <thomas@codesourcery.com>]

Hi!

On Fri, 8 Jan 2016 09:16:55 +0100, Richard Biener <rguenther@suse.de> wrote:
> On Wed, 16 Dec 2015, Tom de Vries wrote:
> > On 10/12/15 14:14, Tom de Vries wrote:
> > > > On Thu, 3 Dec 2015, Tom de Vries wrote:
> > > > > Essentially we have two situations:
> > > > > - in the host compiler, there is no need for the forced_output flag,
> > > > >   and it inhibits optimization
> > > > > - in the accelerator compiler, it (or some equivalent) is needed
> > > 
> > > Actually, things are slightly more complicated, I realize now. There's
> > > also the distinction between:
> > > - symbols declared as offloadable in the source code, and
> > > - symbols create by the compiler and marked offloadable
> > > 
> > > > > I wonder if setting the force_output flag only when streaming the
> > > > > bytecode for
> > > > > offloading would work. That way, it wouldn't be set in the host
> > > > > compiler,
> > > > > while being set in the accelerator compiler.
> > > > 
> > > > Yeah, that was my original thinking btw.
> > > 
> > > FTR, I've tried that approach, as attached. It fixed the
> > > goacc/kernels-alias-ipa-pta*.c failures.

Confirmed.  And, no change in offloading testing when applying the patch
to gomp-4_0-branch (where these FAILs didn't appear to begin with).

> > > And I ran target-libgomp (also
> > > using an accelerator configuration) without any regressions.

Confirmed.

> > How about this patch?
> > 
> > We remove the setting of force_output when:
> > - encountering offloadable symbols in the frontend, or
> > - creating offloadable symbols in expand-omp.
> > 
> > Instead, we set force_output in input_offload_tables.
> > 
> > This is an improvement because:
> > - it moves the force_output setting to a single location
> > - it does the force_output setting ALAP
> 
> Works for me.

Do we need review from Jakub or is this good for trunk?


Grüße
 Thomas