[llvm-commits] [cfe-commits] [PATCH] First OpenMP patch

[Mahesha HS]

On Fri, Nov 23, 2012 at 1:53 AM, Hal Finkel <hfinkel at anl.gov> wrote:
>
> ----- Original Message -----
>> From: "Mahesha HS" <mahesha.llvm at gmail.com>
>> To: "Hal Finkel" <hfinkel at anl.gov>, "Dmitri Gribenko" <gribozavr at gmail.com>
>> Cc: "llvm-commits" <llvm-commits at cs.uiuc.edu>, "Joey Gouly" <joey.gouly at arm.com>, "Benjamin Kramer"
>> <benny.kra at gmail.com>
>> Sent: Wednesday, November 21, 2012 11:52:39 PM
>> Subject: Re: [cfe-commits] [PATCH] First OpenMP patch
>>
>> That is fine. I will experiment with GCC for different flags like -W,
>> -Wall etc. And make sure that the implementation is in compatible
>> with
>> GCC (when it is not really a bug-to-bug compatible). I think, this
>> additional implementation will be on top of what the current patch
>> contains. This, I will send as an another patch.
>
> Makes sense.
>
>>
>> Do you guys agree to the internal requirement for two lang options -
>> OpenMP and NoOpenMP - to keep track of the options -fopenmp and
>> -fno-openmp? If so, I will change the "comment and test case" as
>> mentioned by Joey and re-submit the patch.
>
> If the only purpose of this is to affect the warnings, then Dmitri's suggestion of using something like -Wsource-uses-openmp is (in my opinion) better.

I agree. As of now, it affects only warnings though I do not know
about future requirements. So I will remove "NoOpenMP" for the time
being.

--
mahesha


>
> Thanks again,
> Hal
>
>>
>> --
>> mahesha
>>
>>
>>
>>
>>
>> On Thu, Nov 22, 2012 at 2:09 AM, Hal Finkel <hfinkel at anl.gov> wrote:
>> > ----- Original Message -----
>> >> From: "Dmitri Gribenko" <gribozavr at gmail.com>
>> >> To: "Mahesha HS" <mahesha.llvm at gmail.com>
>> >> Cc: "Benjamin Kramer" <benny.kra at gmail.com>, "llvm cfe"
>> >> <cfe-commits at cs.uiuc.edu>
>> >> Sent: Wednesday, November 21, 2012 11:06:50 AM
>> >> Subject: Re: [cfe-commits] [PATCH] First OpenMP patch
>> >>
>> >> On Wed, Nov 21, 2012 at 6:02 PM, Mahesha HS
>> >> <mahesha.llvm at gmail.com>
>> >> wrote:
>> >> > Though -fopenmp and -fno-openmp are mutually exclusive options,
>> >> > underlying functionality, that we intended to implement differ a
>> >> > little. In a nutshell, we, sometime back discussed in CFE DEV
>> >> > list
>> >> > to
>> >> > implement OpenMP as follows. We thought that passing neither
>> >> > -fopenmp
>> >> > nor -fno-openmp  is not same as passing only -fno-openmp.
>> >> >  Following
>> >> > is the intended implementation. This forced me to add two lang
>> >> > options
>> >> > as I could not handle it using only one lang option. If this was
>> >> > not
>> >> > there, I guess, all your comments would not have araised.
>> >> >
>> >> > if (source contains OpenMP statements) {
>> >> >      if (neither -fopenmp nor -fno-openmp present) {
>> >> >          Throw warning.
>> >> >      }
>> >> >      else if (only -fopenmp present) {
>> >> >          Process OpenMP
>> >> >      }
>> >> >      else if (only -fno-openmp) {
>> >> >         Silently ignore OpenMP. Do not throw warning.
>> >> >      }
>> >> >     else if (both -fopenmp and -fno-openmp are present) {
>> >> >         Decide based on which one appears later in the command
>> >> >         line.
>> >> >     }
>> >> > }
>> >>
>> >> I think the implementation should use the general diagnostics
>> >> infrastructure.  For example, by default add something like
>> >> -Wsource-uses-openmp and disable it in case of -fno-openmp.
>> >>
>> >> $ g++ -W -Wall /tmp/zzz.cc
>> >> /tmp/zzz.cc:3:0: warning: ignoring #pragma omp barrier
>> >> [-Wunknown-pragmas]
>> >>
>> >> By the way, the algorithm above is not consistent with gcc, which
>> >> ignores the pragma when no -f flag is passed.
>> >
>> > I think that we'd like to act the way that gcc does, except that we
>> > don't want to warn about unused OpenMP pragmas when -fno-openmp is
>> > given even if -Wall is also specified.
>> >
>> >  -Hal
>> >
>> >>
>> >> Dmitri
>> >>
>> >> --
>> >> main(i,j){for(i=2;;i++){for(j=2;j<i;j++){if(!(i%j)){j=0;break;}}if
>> >> (j){printf("%d\n",i);}}} /*Dmitri Gribenko <gribozavr at gmail.com>*/
>> >> _______________________________________________
>> >> cfe-commits mailing list
>> >> cfe-commits at cs.uiuc.edu
>> >> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
>> >>
>> >
>> > --
>> > Hal Finkel
>> > Postdoctoral Appointee
>> > Leadership Computing Facility
>> > Argonne National Laboratory
>>
>>
>>
>> --
>> mahesha
>>
>
> --
> Hal Finkel
> Postdoctoral Appointee
> Leadership Computing Facility
> Argonne National Laboratory



-- 
mahesha