revert_kernel.f90

!Crown Copyright 2012 AWE.
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! This file is part of CloverLeaf.
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!>  @brief Fortran revert kernel.
!>  @author Wayne Gaudin
!>  @details Takes the half step field data used in the predictor and reverts
!>  it to the start of step data, ready for the corrector.
!>  Note that this does not seem necessary in this proxy-app but should be
!>  left in to remain relevant to the full method.

MODULE revert_kernel_module

CONTAINS

  SUBROUTINE revert_kernel(x_min,x_max,y_min,y_max,density0,density1,energy0,energy1)

    IMPLICIT NONE

    INTEGER :: x_min,x_max,y_min,y_max
    REAL(KIND=8), DIMENSION(x_min-2:x_max+2,y_min-2:y_max+2)    :: density0
    REAL(KIND=8), DIMENSION(x_min-2:x_max+2,y_min-2:y_max+2)    :: density1
    REAL(KIND=8), DIMENSION(x_min-2:x_max+2,y_min-2:y_max+2)    :: energy0
    REAL(KIND=8), DIMENSION(x_min-2:x_max+2,y_min-2:y_max+2)    :: energy1

    INTEGER :: j,k

!$ACC DATA &
!$ACC PRESENT(density0,energy0,density1,energy1)
!$ACC KERNELS

!$ACC LOOP INDEPENDENT
    DO k=y_min,y_max
!$ACC LOOP INDEPENDENT
      DO j=x_min,x_max
        density1(j,k)=density0(j,k)
        energy1(j,k)=energy0(j,k)
      ENDDO
    ENDDO

!$ACC END KERNELS
!$ACC END DATA


  END SUBROUTINE revert_kernel

END MODULE revert_kernel_module