C $Header: /home/ubuntu/mnt/e9_copy/MITgcm/eesupp/src/exch_uv_xyz_rx.template,v 1.2 2001/05/29 14:01:36 adcroft Exp $
C $Name:  $

#include "CPP_EEOPTIONS.h"

      SUBROUTINE EXCH_UV_XYZ_RX(
     U                       Uphi, Vphi, withSigns,
     I                       myThid )
C     /==========================================================\
C     | SUBROUTINE EXCH_UV_XYZ_RX                                |
C     | o Handle exchanges for _RX,      3-dimensional arrays.   |
C     |==========================================================|
C     | Do true shared-memory data transfers and "messaging"     |
C     | tranfers for blocking case of data transfers.            |
C     | Applications call this routine using                     |
C     |  CALL EXCH..( x, myThid )                                |
C     | where x is a two-dimensional array with overlaps.        |
C     | This routine does true-shared-memory copies for blocks   |
C     | within a thread. It will also do MPI meesaging between   |
C     | different processes.                                     |
C     | Note:                                                    |
C     | =====                                                    |
C     | This routine is a default mode interface to the more     |
C     | general exchange routine. Under default mode the         |
C     | exchange is for an edge width of OLx, and OLy and        |
C     | updates corner points as well as edges ( slightly more   |
C     | synchronisation required).                               |
C     \==========================================================/
      IMPLICIT NONE

C     === Global data ===
#include "SIZE.h"
#include "EEPARAMS.h"
#include "EESUPPORT.h"

C     === Routine arguments ===
C     phi    - Array with overlap regions are to be exchanged
C              Note - The interface to EXCH_RL assumes that
C              the standard Fortran 77 sequence association rules
C              apply.
C     myThid - My thread id.
      _RX Uphi(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
      _RX Vphi(1-OLx:sNx+OLx,1-OLy:sNy+OLy,Nr,nSx,nSy)
      LOGICAL withSigns
      INTEGER myThid
CEndOfInterface

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

      OLw        = OLx
      OLe        = OLx
      OLn        = OLy
      OLs        = OLy
      exchWidthX = OLx
      exchWidthY = OLy
      myNz       = Nr
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 EXCH_UV_RX_CUBE( Uphi, Vphi, withSigns,
     I            OLw, OLe, OLs, OLn, myNz,
     I            exchWidthX, exchWidthY,
     I            FORWARD_SIMULATION, EXCH_UPDATE_CORNERS, myThid )
      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_XYZ_RX( Uphi, myThid )
       _EXCH_XYZ_RX( Vphi, myThid )
      ENDIF

      RETURN
      END