revert_kernel.f90

!Crown Copyright 2012 AWE.
!
! 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,z_min,z_max,density0,density1,energy0,energy1)

  IMPLICIT NONE

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

  INTEGER :: j,k,l

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

!$ACC KERNELS
!$ACC LOOP INDEPENDENT
  DO l=z_min,z_max
!$ACC LOOP INDEPENDENT
    DO k=y_min,y_max
!$ACC LOOP INDEPENDENT
      DO j=x_min,x_max
        density1(j,k,l)=density0(j,k,l)
      ENDDO
    ENDDO
  ENDDO
!$ACC END KERNELS

!$ACC KERNELS
!$ACC LOOP INDEPENDENT
  DO l=z_min,z_max
!$ACC LOOP INDEPENDENT
    DO k=y_min,y_max
!$ACC LOOP INDEPENDENT
      DO j=x_min,x_max
        energy1(j,k,l)=energy0(j,k,l)
      ENDDO
    ENDDO
  ENDDO
!$ACC END KERNELS

!$ACC END DATA

END SUBROUTINE revert_kernel

END MODULE revert_kernel_module