[Openmp-dev] Problem in setting number of threads while using clang with openmp

[Rajat Garg]

Hi Andrey,

This helped but this is not working with polly. If I don't include the
"-fopenmp=libomp", then polly is able to do its specified optimizations,
but if I include this flag, I cannot use polly anymore.

I found something-: https://github.com/clang-omp/clang/issues/44 which
mentions using clang-omp with polly. But, I am not sure.

Can you guys help in this?

Thanks,
Rajat




On Wed, Jul 15, 2015 at 10:46 AM, Andrey Bokhanko <andreybokhanko at gmail.com>
wrote:

> Rajat,
>
> Glad this helped.
>
> As for mentioning "-fopenmp=libomp", today we got one step closer for
> making libomp the default value. So maybe it will go for good soon?
>
> Andrey
>
>
> On Wed, Jul 15, 2015 at 4:43 PM, Rajat Garg <gargx093 at umn.edu> wrote:
> > Hi,
> >
> > Thanks a lot for mentioning "-fopenmp=libomp". This works perfectly fine.
> > Maybe you should should mention this on http://openmp.llvm.org/. I have
> been
> > dealing with this for last two days.
> >
> >
> > Thanks,
> > Rajat
> >
> > On Tue, Jul 14, 2015 at 5:37 PM, Andrey Bokhanko <
> andreybokhanko at gmail.com>
> > wrote:
> >>
> >> Hi Rajat,
> >>
> >> OpenMP 3.1 is fully upstreamed to clang / llvm trunk, so it is better
> >> to use trunk version (unless you have a really good reason to prefer
> >> one hosted on clang-omp.github).
> >>
> >> Instructions are posted on llvm blog:
> >> http://blog.llvm.org/2015/05/openmp-support_22.html. The only
> >> difference is that instead of "-fopenmp" you should use
> >> "-fopenmp=libomp" (this is temporary and will be fixed, but here we
> >> are).
> >>
> >> As for the segmentation fault you got, please try trunk version of the
> >> compiler and if problem won't go away, provide more details: HW and OS
> >> you use, how exactly you built clang, what's inside try.c, etc.
> >>
> >> Yours,
> >> Andrey Bokhanko
> >> =============
> >> Software Engineer
> >> Intel Compiler Team
> >> Intel
> >>
> >>
> >> On Tue, Jul 14, 2015 at 9:03 PM, Rajat Garg <gargx093 at umn.edu> wrote:
> >> > Hi,
> >> >
> >> > I am using the clang provided by polly(which is version 3.7) in
> >> > association
> >> > with openmp shared library(http://openmp.llvm.org/).
> >> >
> >> > Ultimately, I have to run clang with polly on multiple threads. So, I
> >> > tried
> >> > to compile a simple program with #pragma parallel. But I could not
> >> > create
> >> > more than one thread. This was because libgomp was getting linked
> >> > instead of
> >> > libomp.
> >> >
> >> > So, as suggested on https://github.com/clang-omp/clang/issues/44, I
> >> > downloaded the clang-omp version and following the directions as in
> >> > https://clang-omp.github.io/.
> >> >
> >> > ../build/bin/clang-3.5 -fopenmp
> >> > -L/home/rajat/lulesh/openmp/runtime/exports/lin_32e/lib/
> >> > -I/home/rajat/lulesh/openmp/runtime/exports/common/include try.c
> >> >
> >> > But, this gives segmentation fault with #pragma omp parallel.
> >> >
> >> > Can you help me out in this.
> >> >
> >> > Thanks,
> >> > Rajat
> >> >
> >> > _______________________________________________
> >> > Openmp-dev mailing list
> >> > Openmp-dev at dcs-maillist2.engr.illinois.edu
> >> > http://lists.cs.uiuc.edu/mailman/listinfo/openmp-dev
> >> >
> >
> >
> >
> >
> > --
> > Rajat
>



-- 
Rajat
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/openmp-dev/attachments/20150715/95749240/attachment.html>