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update_halo_kernel.f90
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update_halo_kernel.f90
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!Crown Copyright 2012 AWE.
!
! This file is part of CloverLeaf.
!
! CloverLeaf is free software: you can redistribute it and/or modify it under
! the terms of the GNU General Public License as published by the
! Free Software Foundation, either version 3 of the License, or (at your option)
! any later version.
!
! CloverLeaf is distributed in the hope that it will be useful, but
! WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
! FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
! details.
!
! You should have received a copy of the GNU General Public License along with
! CloverLeaf. If not, see http://www.gnu.org/licenses/.
!> @brief Fortran kernel to update the external halo cells in a chunk.
!> @author Wayne Gaudin
!> @details Updates halo cells for the required fields at the required depth
!> for any halo cells that lie on an external boundary. The location and type
!> of data governs how this is carried out. External boundaries are always
!> reflective.
MODULE update_halo_kernel_module
CONTAINS
SUBROUTINE update_halo_kernel(x_min,x_max,y_min,y_max, &
chunk_neighbours, &
density0, &
energy0, &
pressure, &
viscosity, &
soundspeed, &
density1, &
energy1, &
xvel0, &
yvel0, &
xvel1, &
yvel1, &
vol_flux_x, &
vol_flux_y, &
mass_flux_x, &
mass_flux_y, &
fields, &
depth )
IMPLICIT NONE
INTEGER :: x_min,x_max,y_min,y_max
INTEGER, DIMENSION(4) :: chunk_neighbours
REAL(KIND=8), DIMENSION(x_min-2:x_max+2,y_min-2:y_max+2) :: density0,energy0
REAL(KIND=8), DIMENSION(x_min-2:x_max+2,y_min-2:y_max+2) :: pressure,viscosity,soundspeed
REAL(KIND=8), DIMENSION(x_min-2:x_max+2,y_min-2:y_max+2) :: density1,energy1
REAL(KIND=8), DIMENSION(x_min-2:x_max+3,y_min-2:y_max+3) :: xvel0,yvel0
REAL(KIND=8), DIMENSION(x_min-2:x_max+3,y_min-2:y_max+3) :: xvel1,yvel1
REAL(KIND=8), DIMENSION(x_min-2:x_max+3,y_min-2:y_max+2) :: vol_flux_x,mass_flux_x
REAL(KIND=8), DIMENSION(x_min-2:x_max+2,y_min-2:y_max+3) :: vol_flux_y,mass_flux_y
INTEGER :: fields(:),depth
! These need to be kept consistent with the data module to avoid use statement
INTEGER, PARAMETER :: CHUNK_LEFT =1 &
,CHUNK_RIGHT =2 &
,CHUNK_BOTTOM =3 &
,CHUNK_TOP =4 &
,EXTERNAL_FACE=-1
INTEGER, PARAMETER :: FIELD_DENSITY0 = 1 &
,FIELD_DENSITY1 = 2 &
,FIELD_ENERGY0 = 3 &
,FIELD_ENERGY1 = 4 &
,FIELD_PRESSURE = 5 &
,FIELD_VISCOSITY = 6 &
,FIELD_SOUNDSPEED = 7 &
,FIELD_XVEL0 = 8 &
,FIELD_XVEL1 = 9 &
,FIELD_YVEL0 =10 &
,FIELD_YVEL1 =11 &
,FIELD_VOL_FLUX_X =12 &
,FIELD_VOL_FLUX_Y =13 &
,FIELD_MASS_FLUX_X=14 &
,FIELD_MASS_FLUX_Y=15
INTEGER :: j,k
! Update values in external halo cells based on depth and fields requested
! Even though half of these loops look the wrong way around, it should be noted
! that depth is either 1 or 2 so that it is more efficient to always thread
! loop along the mesh edge.
IF(fields(FIELD_DENSITY0).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
density0(j,1-k)=density0(j,0+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
density0(j,y_max+k)=density0(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
density0(1-j,k)=density0(0+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
density0(x_max+j,k)=density0(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_DENSITY1).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
density1(j,1-k)=density1(j,0+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
density1(j,y_max+k)=density1(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
density1(1-j,k)=density1(0+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
density1(x_max+j,k)=density1(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_ENERGY0).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
energy0(j,1-k)=energy0(j,0+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
energy0(j,y_max+k)=energy0(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
energy0(1-j,k)=energy0(0+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
energy0(x_max+j,k)=energy0(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_ENERGY1).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
energy1(j,1-k)=energy1(j,0+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
energy1(j,y_max+k)=energy1(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
energy1(1-j,k)=energy1(0+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
energy1(x_max+j,k)=energy1(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_PRESSURE).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
pressure(j,1-k)=pressure(j,0+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
pressure(j,y_max+k)=pressure(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
pressure(1-j,k)=pressure(0+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
pressure(x_max+j,k)=pressure(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_VISCOSITY).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
viscosity(j,1-k)=viscosity(j,0+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
viscosity(j,y_max+k)=viscosity(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
viscosity(1-j,k)=viscosity(0+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
viscosity(x_max+j,k)=viscosity(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_SOUNDSPEED).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
soundspeed(j,1-k)=soundspeed(j,0+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
soundspeed(j,y_max+k)=soundspeed(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
soundspeed(1-j,k)=soundspeed(0+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
soundspeed(x_max+j,k)=soundspeed(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_XVEL0).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
xvel0(j,1-k)=xvel0(j,1+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
xvel0(j,y_max+1+k)=xvel0(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
xvel0(1-j,k)=-xvel0(1+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
xvel0(x_max+1+j,k)=-xvel0(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_XVEL1).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
xvel1(j,1-k)=xvel1(j,1+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
xvel1(j,y_max+1+k)=xvel1(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
xvel1(1-j,k)=-xvel1(1+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
xvel1(x_max+1+j,k)=-xvel1(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_YVEL0).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
yvel0(j,1-k)=-yvel0(j,1+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
yvel0(j,y_max+1+k)=-yvel0(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
yvel0(1-j,k)=yvel0(1+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
yvel0(x_max+1+j,k)=yvel0(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_YVEL1).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
yvel1(j,1-k)=-yvel1(j,1+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
yvel1(j,y_max+1+k)=-yvel1(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
yvel1(1-j,k)=yvel1(1+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
yvel1(x_max+1+j,k)=yvel1(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_VOL_FLUX_X).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
vol_flux_x(j,1-k)=vol_flux_x(j,1+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
vol_flux_x(j,y_max+k)=vol_flux_x(j,y_max-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
vol_flux_x(1-j,k)=-vol_flux_x(1+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
vol_flux_x(x_max+j+1,k)=-vol_flux_x(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_MASS_FLUX_X).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
mass_flux_x(j,1-k)=mass_flux_x(j,1+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+1+depth
DO k=1,depth
mass_flux_x(j,y_max+k)=mass_flux_x(j,y_max-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
mass_flux_x(1-j,k)=-mass_flux_x(1+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+depth
DO j=1,depth
mass_flux_x(x_max+j+1,k)=-mass_flux_x(x_max+1-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_VOL_FLUX_Y).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
vol_flux_y(j,1-k)=-vol_flux_y(j,1+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
vol_flux_y(j,y_max+k+1)=-vol_flux_y(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
vol_flux_y(1-j,k)=vol_flux_y(1+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
vol_flux_y(x_max+j,k)=vol_flux_y(x_max-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
IF(fields(FIELD_MASS_FLUX_Y).EQ.1) THEN
IF(chunk_neighbours(CHUNK_BOTTOM).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
mass_flux_y(j,1-k)=-mass_flux_y(j,1+k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_TOP).EQ.EXTERNAL_FACE) THEN
DO j=x_min-depth,x_max+depth
DO k=1,depth
mass_flux_y(j,y_max+k+1)=-mass_flux_y(j,y_max+1-k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_LEFT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
mass_flux_y(1-j,k)=mass_flux_y(1+j,k)
ENDDO
ENDDO
ENDIF
IF(chunk_neighbours(CHUNK_RIGHT).EQ.EXTERNAL_FACE) THEN
DO k=y_min-depth,y_max+1+depth
DO j=1,depth
mass_flux_y(x_max+j,k)=mass_flux_y(x_max-j,k)
ENDDO
ENDDO
ENDIF
ENDIF
END SUBROUTINE update_halo_kernel
END MODULE update_halo_kernel_module