libgomp/testsuite/libgomp.fortran/omp_workshare2.f

   1 C******************************************************************************
   2 C FILE: omp_workshare2.f
   3 C DESCRIPTION:
   4 C   OpenMP Example - Sections Work-sharing - Fortran Version
   5 C   In this example, the OpenMP SECTION directive is used to assign
   6 C   different array operations to threads that execute a SECTION. Each
   7 C   thread receives its own copy of the result array to work with.
   8 C AUTHOR: Blaise Barney  5/99
   9 C LAST REVISED: 01/09/04
  10 C******************************************************************************
  11
  12       PROGRAM WORKSHARE2
  13
  14       INTEGER N, I, NTHREADS, TID, OMP_GET_NUM_THREADS,
  15      +        OMP_GET_THREAD_NUM
  16       PARAMETER (N=50)
  17       REAL A(N), B(N), C(N)
  18
  19 !     Some initializations
  20       DO I = 1, N
  21         A(I) = I * 1.0
  22         B(I) = A(I)
  23       ENDDO
  24
  25 !$OMP PARALLEL SHARED(A,B,NTHREADS), PRIVATE(C,I,TID)
  26       TID = OMP_GET_THREAD_NUM()
  27       IF (TID .EQ. 0) THEN
  28         NTHREADS = OMP_GET_NUM_THREADS()
  29         PRINT *, 'Number of threads =', NTHREADS
  30       END IF
  31       PRINT *, 'Thread',TID,' starting...'
  32
  33 !$OMP SECTIONS
  34
  35 !$OMP SECTION
  36       PRINT *, 'Thread',TID,' doing section 1'
  37       DO I = 1, N
  38          C(I) = A(I) + B(I)
  39          WRITE(*,100) TID,I,C(I)
  40  100     FORMAT(' Thread',I2,': C(',I2,')=',F8.2)
  41       ENDDO
  42
  43 !$OMP SECTION
  44       PRINT *, 'Thread',TID,' doing section 2'
  45       DO I = 1+N/2, N
  46          C(I) = A(I) * B(I)
  47          WRITE(*,100) TID,I,C(I)
  48       ENDDO
  49
  50 !$OMP END SECTIONS NOWAIT
  51
  52       PRINT *, 'Thread',TID,' done.'
  53
  54 !$OMP END PARALLEL
  55
  56       END