How to break out of a nested parallel (OpenMP) Fortran loop idiomatically?

Posted by J.F. Sebastian on Stack Overflow See other posts from Stack Overflow or by J.F. Sebastian
Published on 2010-06-05T09:02:32Z Indexed on 2010/06/05 9:12 UTC
Read the original article Hit count: 311

Filed under:

fortran

|

openmp

|

break

|

omp

|

parallel-loop

Here's sequential code:

do i = 1, n
   do j = i+1, n
      if ("some_condition") then
         result = "here's result"
         return
      end if
   end do
end do

Is there a cleaner way to execute iterations of the outer loop concurrently other than:

  !$OMP PARALLEL private(i,j)
  !$OMP DO 
  do i = 1, n     
     if (found) goto 10
     do j = i+1, n        
        if (found) goto 10
        if ("some_condition") then
           !$OMP CRITICAL
           !$OMP FLUSH
           if (.not.found) then           
              found = .true.
              result = "here's result"
           end if
           !$OMP FLUSH
           !$OMP END CRITICAL
           goto 10
        end if
     end do
10   continue
  end do
  !$OMP END DO NOWAIT
  !$OMP END PARALLEL

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