45 lines
1.2 KiB
Fortran
45 lines
1.2 KiB
Fortran
C******************************************************************************
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C FILE: omp_orphan.f
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C DESCRIPTION:
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C OpenMP Example - Parallel region with an orphaned directive - Fortran
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C Version
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C This example demonstrates a dot product being performed by an orphaned
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C loop reduction construct. Scoping of the reduction variable is critical.
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C AUTHOR: Blaise Barney 5/99
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C LAST REVISED:
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C******************************************************************************
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PROGRAM ORPHAN
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COMMON /DOTDATA/ A, B, SUM
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INTEGER I, VECLEN
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PARAMETER (VECLEN = 100)
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REAL*8 A(VECLEN), B(VECLEN), SUM
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DO I=1, VECLEN
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A(I) = 1.0 * I
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B(I) = A(I)
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ENDDO
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SUM = 0.0
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!$OMP PARALLEL
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CALL DOTPROD
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!$OMP END PARALLEL
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WRITE(*,*) "Sum = ", SUM
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END
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SUBROUTINE DOTPROD
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COMMON /DOTDATA/ A, B, SUM
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INTEGER I, TID, OMP_GET_THREAD_NUM, VECLEN
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PARAMETER (VECLEN = 100)
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REAL*8 A(VECLEN), B(VECLEN), SUM
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TID = OMP_GET_THREAD_NUM()
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!$OMP DO REDUCTION(+:SUM)
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DO I=1, VECLEN
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SUM = SUM + (A(I)*B(I))
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PRINT *, ' TID= ',TID,'I= ',I
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ENDDO
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RETURN
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END
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