C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/pkg/exch2/Attic/exch2_uv_xy_rx.template,v 1.1 2004/01/09 20:46:09 afe Exp $
C $Name:  $

#include "CPP_EEOPTIONS.h"

CBOP
C     !ROUTINE: EXCH_UV_XY_RX

C     !INTERFACE:
      SUBROUTINE EXCH2_UV_XY_RX(
     U                       Uphi, Vphi, withSigns,
     I                       myThid )
      IMPLICIT NONE
C     !DESCRIPTION:
C     *==========================================================*
C     | SUBROUTINE EXCH_UV_XY_RX                                  
C     | o Handle exchanges for _RX, two-dimensional arrays.    
C     *==========================================================*
C     | Driver exchange routine which branches to cube sphere or
C     | global, simple cartesian index grid. Exchange routine is
C     | called with two arrays that are components of a vector.
C     | These components are rotated and interchanged on the 
C     | rotated grid during cube exchanges.
C     *==========================================================*

C     !USES:
C     === Global data ===
#include "SIZE.h"
#include "EEPARAMS.h"
#include "EESUPPORT.h"
#include "W2_EXCH2_TOPOLOGY.h"
#include "W2_EXCH2_PARAMS.h"

C     !INPUT/OUTPUT PARAMETERS:
C     === Routine arguments ===
C     Uphi      :: Arrays with overlap regions are to be exchanged
C     Vphi         Note - The interface to EXCH_ assumes that
C                  the standard Fortran 77 sequence association rules
C                  apply.
C     myThid    :: My thread id.
C     withSigns :: Flag controlling whether vector is signed.
      _RX Uphi(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
      _RX Vphi(1-OLx:sNx+OLx,1-OLy:sNy+OLy,nSx,nSy)
      LOGICAL withSigns
      INTEGER myThid

C     !LOCAL VARIABLES:
C     == Local variables ==
C     OL[wens]       :: Overlap extents in west, east, north, south.
C     exchWidth[XY]  :: Extent of regions that will be exchanged.
      INTEGER OLw, OLe, OLn, OLs, exchWidthX, exchWidthY, myNz
      INTEGER bi, bj, myTile
CEOP

      OLw        = OLx
      OLe        = OLx
      OLn        = OLy
      OLs        = OLy
      exchWidthX = OLx
      exchWidthY = OLy
      myNz       = 1
C     ** NOTE ** The exchange routine we use here does not
C                require the preceeding and following barriers.
C                However, the slow, simple exchange interface
C                that is calling it here is meant to ensure
C                that threads are synchronised before exchanges
C                begine.
      IF (useCubedSphereExchange) THEN
       CALL EXCH2_RX2_CUBE( Uphi, Vphi, withSigns, 'UV',
     I            OLw, OLe, OLs, OLn, myNz,
     I            exchWidthX, exchWidthY,
     I            FORWARD_SIMULATION, EXCH_UPDATE_CORNERS, myThid )
       CALL EXCH2_RX2_CUBE( Uphi, Vphi, withSigns, 'UV',
     I            OLw, OLe, OLs, OLn, myNz,
     I            exchWidthX, exchWidthY,
     I            FORWARD_SIMULATION, EXCH_UPDATE_CORNERS, myThid )
       DO bj=myByLo(myThid),myByHi(myThid)
        DO bi=myBxLo(myThid),myBxHi(myThid)
         myTile = W2_myTileList(bi)
         IF ( exch2_isEedge(myTile) .EQ. 1 .AND.
     &        exch2_isSedge(myTile) .EQ. 1 ) THEN
          Uphi(snx+1,    0,bi,bj)= vPhi(snx+1,    1,bi,bj)
         ENDIF
         IF ( withSigns ) THEN
          IF ( exch2_isEedge(myTile) .EQ. 1 .AND.
     &         exch2_isNedge(myTile) .EQ. 1 ) THEN
           Uphi(snx+1,sny+1,bi,bj)=-vPhi(snx+1,sny+1,bi,bj)
          ENDIF
         ELSE
          IF ( exch2_isEedge(myTile) .EQ. 1 .AND.
     &         exch2_isNedge(myTile) .EQ. 1 ) THEN
           Uphi(snx+1,sny+1,bi,bj)= vPhi(snx+1,sny+1,bi,bj)
          ENDIF
         ENDIF
        ENDDO
       ENDDO

      ELSE
c      CALL EXCH_RX( Uphi,
c    I            OLw, OLe, OLs, OLn, myNz,
c    I            exchWidthX, exchWidthY,
c    I            FORWARD_SIMULATION, EXCH_UPDATE_CORNERS, myThid )
c      CALL EXCH_RX( Vphi,
c    I            OLw, OLe, OLs, OLn, myNz,
c    I            exchWidthX, exchWidthY,
c    I            FORWARD_SIMULATION, EXCH_UPDATE_CORNERS, myThid )
c_jmc: for JAM compatibility, replace the 2 CALLs above by the 2 CPP_MACROs:
       _EXCH_XY_RX( Uphi, myThid )
       _EXCH_XY_RX( Vphi, myThid )
      ENDIF

      RETURN
      END