| 1 | !> @file exchange_horiz.f90 |
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| 2 | !------------------------------------------------------------------------------! |
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| 3 | ! This file is part of the PALM model system. |
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| 4 | ! |
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| 5 | ! PALM is free software: you can redistribute it and/or modify it under the |
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| 6 | ! terms of the GNU General Public License as published by the Free Software |
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| 7 | ! Foundation, either version 3 of the License, or (at your option) any later |
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| 8 | ! version. |
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| 9 | ! |
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| 10 | ! PALM is distributed in the hope that it will be useful, but WITHOUT ANY |
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| 11 | ! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR |
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| 12 | ! A PARTICULAR PURPOSE. See the GNU General Public License for more details. |
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| 13 | ! |
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| 14 | ! You should have received a copy of the GNU General Public License along with |
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| 15 | ! PALM. If not, see <http://www.gnu.org/licenses/>. |
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| 16 | ! |
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| 17 | ! Copyright 1997-2020 Leibniz Universitaet Hannover |
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| 18 | !------------------------------------------------------------------------------! |
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| 19 | ! |
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| 20 | ! Current revisions: |
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| 21 | ! ----------------- |
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| 22 | ! |
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| 23 | ! |
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| 24 | ! Former revisions: |
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| 25 | ! ----------------- |
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| 26 | ! $Id: exchange_horiz.f90 4429 2020-02-27 15:24:30Z raasch $ |
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| 27 | ! bugfix: cpp-directives added for serial mode |
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| 28 | ! |
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| 29 | ! 4360 2020-01-07 11:25:50Z suehring |
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| 30 | ! Corrected "Former revisions" section |
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| 31 | ! |
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| 32 | ! 3761 2019-02-25 15:31:42Z raasch |
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| 33 | ! OpenACC directives re-formatted |
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| 34 | ! |
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| 35 | ! 3657 2019-01-07 20:14:18Z knoop |
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| 36 | ! OpenACC port for SPEC |
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| 37 | ! |
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| 38 | ! Revision 1.1 1997/07/24 11:13:29 raasch |
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| 39 | ! Initial revision |
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| 40 | ! |
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| 41 | ! |
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| 42 | ! Description: |
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| 43 | ! ------------ |
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| 44 | !> Exchange of lateral boundary values (parallel computers) and cyclic |
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| 45 | !> lateral boundary conditions, respectively. |
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| 46 | !------------------------------------------------------------------------------! |
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| 47 | SUBROUTINE exchange_horiz( ar, nbgp_local) |
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| 48 | |
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| 49 | |
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| 50 | USE control_parameters, & |
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| 51 | ONLY: bc_lr_cyc, bc_ns_cyc |
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| 52 | |
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| 53 | #if defined( __parallel ) |
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| 54 | USE control_parameters, & |
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| 55 | ONLY: grid_level, mg_switch_to_pe0, synchronous_exchange |
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| 56 | #endif |
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| 57 | |
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| 58 | USE cpulog, & |
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| 59 | ONLY: cpu_log, log_point_s |
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| 60 | |
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| 61 | USE indices, & |
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| 62 | ONLY: nxl, nxr, nyn, nys, nzb, nzt |
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| 63 | |
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| 64 | USE kinds |
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| 65 | |
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| 66 | USE pegrid |
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| 67 | |
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| 68 | IMPLICIT NONE |
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| 69 | |
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| 70 | |
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| 71 | #if defined( _OPENACC ) |
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| 72 | INTEGER(iwp) :: i !< |
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| 73 | #endif |
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| 74 | |
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| 75 | INTEGER(iwp) :: nbgp_local !< |
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| 76 | |
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| 77 | REAL(wp), DIMENSION(nzb:nzt+1,nys-nbgp_local:nyn+nbgp_local, & |
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| 78 | nxl-nbgp_local:nxr+nbgp_local) :: ar !< |
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| 79 | |
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| 80 | |
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| 81 | CALL cpu_log( log_point_s(2), 'exchange_horiz', 'start' ) |
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| 82 | |
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| 83 | #if defined( _OPENACC ) |
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| 84 | !$ACC UPDATE IF_PRESENT ASYNC(1) & |
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| 85 | !$ACC HOST(ar(:,:,nxr-nbgp_local+1:nxr)) & |
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| 86 | !$ACC HOST(ar(:,:,nxl:nxl+nbgp_local-1)) |
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| 87 | |
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| 88 | ! |
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| 89 | !-- Wait for first UPDATE to complete before starting the others. |
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| 90 | !$ACC WAIT(1) ASYNC(2) |
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| 91 | ! ar(:,:,nxl-nbgp_local:nxl-1) is overwritten by first part below |
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| 92 | ! ar(:,:,nxl:nxl+nbgp_local-1) has been transferred above |
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| 93 | DO i = nxl+nbgp_local, nxr-nbgp_local |
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| 94 | !$ACC UPDATE IF_PRESENT ASYNC(2) & |
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| 95 | !$ACC HOST(ar(:,nyn-nbgp_local+1:nyn,i)) & |
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| 96 | !$ACC HOST(ar(:,nys:nys+nbgp_local-1,i)) |
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| 97 | ENDDO |
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| 98 | ! ar(:,:,nxr-nbgp_local+1:nxr) has been transferred above |
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| 99 | ! ar(:,:,nxr+1:nxr+nbgp_local) is overwritten by first part below |
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| 100 | |
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| 101 | ! |
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| 102 | !-- Wait for first UPDATE to complete before starting MPI. |
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| 103 | !$ACC WAIT(1) |
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| 104 | #endif |
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| 105 | |
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| 106 | #if defined( __parallel ) |
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| 107 | |
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| 108 | ! |
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| 109 | !-- Exchange in x-direction of lateral boundaries |
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| 110 | IF ( pdims(1) == 1 .OR. mg_switch_to_pe0 ) THEN |
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| 111 | ! |
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| 112 | !-- One-dimensional decomposition along y, boundary values can be exchanged |
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| 113 | !-- within the PE memory |
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| 114 | IF ( bc_lr_cyc ) THEN |
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| 115 | ar(:,:,nxl-nbgp_local:nxl-1) = ar(:,:,nxr-nbgp_local+1:nxr) |
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| 116 | ar(:,:,nxr+1:nxr+nbgp_local) = ar(:,:,nxl:nxl+nbgp_local-1) |
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| 117 | ENDIF |
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| 118 | |
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| 119 | ELSE |
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| 120 | |
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| 121 | IF ( synchronous_exchange ) THEN |
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| 122 | ! |
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| 123 | !-- Send left boundary, receive right one (synchronous) |
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| 124 | CALL MPI_SENDRECV( & |
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| 125 | ar(nzb,nys-nbgp_local,nxl), 1, type_yz(grid_level), pleft, 0, & |
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| 126 | ar(nzb,nys-nbgp_local,nxr+1), 1, type_yz(grid_level), pright, 0, & |
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| 127 | comm2d, status, ierr ) |
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| 128 | ! |
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| 129 | !-- Send right boundary, receive left one (synchronous) |
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| 130 | CALL MPI_SENDRECV( ar(nzb,nys-nbgp_local,nxr+1-nbgp_local), 1, & |
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| 131 | type_yz(grid_level), pright, 1, & |
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| 132 | ar(nzb,nys-nbgp_local,nxl-nbgp_local), 1, & |
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| 133 | type_yz(grid_level), pleft, 1, & |
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| 134 | comm2d, status, ierr ) |
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| 135 | |
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| 136 | ELSE |
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| 137 | |
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| 138 | ! |
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| 139 | !-- Asynchroneous exchange |
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| 140 | IF ( send_receive == 'lr' .OR. send_receive == 'al' ) THEN |
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| 141 | |
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| 142 | req(1:4) = 0 |
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| 143 | req_count = 0 |
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| 144 | ! |
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| 145 | !-- Send left boundary, receive right one (asynchronous) |
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| 146 | CALL MPI_ISEND( ar(nzb,nys-nbgp_local,nxl), 1, type_yz(grid_level), & |
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| 147 | pleft, req_count, comm2d, req(req_count+1), ierr ) |
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| 148 | CALL MPI_IRECV( ar(nzb,nys-nbgp_local,nxr+1), 1, type_yz(grid_level), & |
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| 149 | pright, req_count, comm2d, req(req_count+2), ierr ) |
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| 150 | ! |
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| 151 | !-- Send right boundary, receive left one (asynchronous) |
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| 152 | CALL MPI_ISEND( ar(nzb,nys-nbgp_local,nxr+1-nbgp_local), 1, & |
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| 153 | type_yz(grid_level), pright, req_count+1, comm2d, & |
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| 154 | req(req_count+3), ierr ) |
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| 155 | CALL MPI_IRECV( ar(nzb,nys-nbgp_local,nxl-nbgp_local), 1, & |
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| 156 | type_yz(grid_level), pleft, req_count+1, comm2d, & |
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| 157 | req(req_count+4), ierr ) |
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| 158 | |
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| 159 | CALL MPI_WAITALL( 4, req, wait_stat, ierr ) |
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| 160 | |
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| 161 | ENDIF |
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| 162 | |
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| 163 | ENDIF |
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| 164 | |
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| 165 | ENDIF |
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| 166 | |
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| 167 | !$ACC UPDATE IF_PRESENT ASYNC(1) & |
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| 168 | !$ACC DEVICE(ar(:,:,nxl-nbgp_local:nxl-1)) & |
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| 169 | !$ACC DEVICE(ar(:,:,nxr+1:nxr+nbgp_local)) |
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| 170 | |
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| 171 | ! |
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| 172 | !-- Wait for UPDATES above to complete before starting MPI. |
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| 173 | !$ACC WAIT(2) |
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| 174 | |
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| 175 | IF ( pdims(2) == 1 .OR. mg_switch_to_pe0 ) THEN |
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| 176 | ! |
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| 177 | !-- One-dimensional decomposition along x, boundary values can be exchanged |
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| 178 | !-- within the PE memory |
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| 179 | IF ( bc_ns_cyc ) THEN |
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| 180 | ar(:,nys-nbgp_local:nys-1,:) = ar(:,nyn-nbgp_local+1:nyn,:) |
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| 181 | ar(:,nyn+1:nyn+nbgp_local,:) = ar(:,nys:nys+nbgp_local-1,:) |
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| 182 | ENDIF |
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| 183 | |
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| 184 | ELSE |
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| 185 | |
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| 186 | IF ( synchronous_exchange ) THEN |
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| 187 | ! |
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| 188 | !-- Send front boundary, receive rear one (synchronous) |
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| 189 | CALL MPI_SENDRECV( & |
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| 190 | ar(nzb,nys,nxl-nbgp_local), 1, type_xz(grid_level), psouth, 0, & |
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| 191 | ar(nzb,nyn+1,nxl-nbgp_local), 1, type_xz(grid_level), pnorth, 0, & |
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| 192 | comm2d, status, ierr ) |
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| 193 | ! |
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| 194 | !-- Send rear boundary, receive front one (synchronous) |
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| 195 | CALL MPI_SENDRECV( ar(nzb,nyn-nbgp_local+1,nxl-nbgp_local), 1, & |
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| 196 | type_xz(grid_level), pnorth, 1, & |
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| 197 | ar(nzb,nys-nbgp_local,nxl-nbgp_local), 1, & |
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| 198 | type_xz(grid_level), psouth, 1, & |
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| 199 | comm2d, status, ierr ) |
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| 200 | |
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| 201 | ELSE |
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| 202 | |
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| 203 | ! |
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| 204 | !-- Asynchroneous exchange |
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| 205 | IF ( send_receive == 'ns' .OR. send_receive == 'al' ) THEN |
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| 206 | |
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| 207 | req(1:4) = 0 |
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| 208 | req_count = 0 |
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| 209 | |
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| 210 | ! |
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| 211 | !-- Send front boundary, receive rear one (asynchronous) |
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| 212 | CALL MPI_ISEND( ar(nzb,nys,nxl-nbgp_local), 1, type_xz(grid_level), & |
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| 213 | psouth, req_count, comm2d, req(req_count+1), ierr ) |
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| 214 | CALL MPI_IRECV( ar(nzb,nyn+1,nxl-nbgp_local), 1, type_xz(grid_level), & |
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| 215 | pnorth, req_count, comm2d, req(req_count+2), ierr ) |
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| 216 | ! |
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| 217 | !-- Send rear boundary, receive front one (asynchronous) |
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| 218 | CALL MPI_ISEND( ar(nzb,nyn-nbgp_local+1,nxl-nbgp_local), 1, & |
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| 219 | type_xz(grid_level), pnorth, req_count+1, comm2d, & |
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| 220 | req(req_count+3), ierr ) |
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| 221 | CALL MPI_IRECV( ar(nzb,nys-nbgp_local,nxl-nbgp_local), 1, & |
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| 222 | type_xz(grid_level), psouth, req_count+1, comm2d, & |
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| 223 | req(req_count+4), ierr ) |
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| 224 | |
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| 225 | CALL MPI_WAITALL( 4, req, wait_stat, ierr ) |
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| 226 | |
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| 227 | ENDIF |
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| 228 | |
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| 229 | ENDIF |
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| 230 | |
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| 231 | ENDIF |
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| 232 | |
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| 233 | #else |
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| 234 | |
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| 235 | ! |
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| 236 | !-- Lateral boundary conditions in the non-parallel case. |
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| 237 | !-- Case dependent, because in GPU mode still not all arrays are on device. This |
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| 238 | !-- workaround has to be removed later. Also, since PGI compiler 12.5 has problems |
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| 239 | !-- with array syntax, explicit loops are used. |
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| 240 | IF ( bc_lr_cyc ) THEN |
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| 241 | ar(:,:,nxl-nbgp_local:nxl-1) = ar(:,:,nxr-nbgp_local+1:nxr) |
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| 242 | ar(:,:,nxr+1:nxr+nbgp_local) = ar(:,:,nxl:nxl+nbgp_local-1) |
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| 243 | ENDIF |
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| 244 | |
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| 245 | !$ACC UPDATE IF_PRESENT ASYNC(1) & |
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| 246 | !$ACC DEVICE(ar(:,:,nxl-nbgp_local:nxl-1)) & |
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| 247 | !$ACC DEVICE(ar(:,:,nxr+1:nxr+nbgp_local)) |
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| 248 | |
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| 249 | ! |
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| 250 | !-- Wait for UPDATES above to complete before starting MPI. |
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| 251 | !$ACC WAIT(2) |
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| 252 | |
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| 253 | IF ( bc_ns_cyc ) THEN |
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| 254 | ar(:,nys-nbgp_local:nys-1,:) = ar(:,nyn-nbgp_local+1:nyn,:) |
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| 255 | ar(:,nyn+1:nyn+nbgp_local,:) = ar(:,nys:nys+nbgp_local-1,:) |
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| 256 | ENDIF |
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| 257 | |
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| 258 | #endif |
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| 259 | |
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| 260 | #if defined( _OPENACC ) |
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| 261 | DO i = nxl-nbgp_local, nxr+nbgp_local |
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| 262 | !$ACC UPDATE IF_PRESENT ASYNC(2) & |
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| 263 | !$ACC DEVICE(ar(:,nys-nbgp_local:nys-1,i)) & |
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| 264 | !$ACC DEVICE(ar(:,nyn+1:nyn+nbgp_local,i)) |
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| 265 | ENDDO |
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| 266 | |
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| 267 | ! |
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| 268 | !-- Wait for all UPDATEs to finish. |
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| 269 | !$ACC WAIT |
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| 270 | #endif |
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| 271 | |
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| 272 | CALL cpu_log( log_point_s(2), 'exchange_horiz', 'stop' ) |
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| 273 | |
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| 274 | END SUBROUTINE exchange_horiz |
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| 275 | |
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| 276 | |
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| 277 | !------------------------------------------------------------------------------! |
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| 278 | ! Description: |
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| 279 | ! ------------ |
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| 280 | !> @todo Missing subroutine description. |
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| 281 | !------------------------------------------------------------------------------! |
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| 282 | SUBROUTINE exchange_horiz_int( ar, nys_l, nyn_l, nxl_l, nxr_l, nzt_l, nbgp_local ) |
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| 283 | |
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| 284 | |
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| 285 | USE control_parameters, & |
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| 286 | ONLY: bc_lr_cyc, bc_ns_cyc |
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| 287 | |
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| 288 | #if defined( __parallel ) |
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| 289 | USE control_parameters, & |
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| 290 | ONLY: grid_level |
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| 291 | #endif |
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| 292 | |
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| 293 | USE indices, & |
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| 294 | ONLY: nzb |
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| 295 | |
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| 296 | USE kinds |
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| 297 | |
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| 298 | USE pegrid |
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| 299 | |
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| 300 | IMPLICIT NONE |
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| 301 | |
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| 302 | INTEGER(iwp) :: nxl_l !< local index bound at current grid level, left side |
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| 303 | INTEGER(iwp) :: nxr_l !< local index bound at current grid level, right side |
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| 304 | INTEGER(iwp) :: nyn_l !< local index bound at current grid level, north side |
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| 305 | INTEGER(iwp) :: nys_l !< local index bound at current grid level, south side |
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| 306 | INTEGER(iwp) :: nzt_l !< local index bound at current grid level, top |
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| 307 | INTEGER(iwp) :: nbgp_local !< number of ghost points |
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| 308 | |
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| 309 | INTEGER(iwp), DIMENSION(nzb:nzt_l+1,nys_l-nbgp_local:nyn_l+nbgp_local, & |
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| 310 | nxl_l-nbgp_local:nxr_l+nbgp_local) :: ar !< treated array |
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| 311 | |
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| 312 | |
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| 313 | #if defined( __parallel ) |
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| 314 | IF ( pdims(1) == 1 ) THEN |
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| 315 | ! |
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| 316 | !-- One-dimensional decomposition along y, boundary values can be exchanged |
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| 317 | !-- within the PE memory |
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| 318 | IF ( bc_lr_cyc ) THEN |
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| 319 | ar(:,:,nxl_l-nbgp_local:nxl_l-1) = ar(:,:,nxr_l-nbgp_local+1:nxr_l) |
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| 320 | ar(:,:,nxr_l+1:nxr_l+nbgp_local) = ar(:,:,nxl_l:nxl_l+nbgp_local-1) |
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| 321 | ENDIF |
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| 322 | ELSE |
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| 323 | ! |
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| 324 | !-- Send left boundary, receive right one (synchronous) |
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| 325 | CALL MPI_SENDRECV( & |
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| 326 | ar(nzb,nys_l-nbgp_local,nxl_l), 1, type_yz_int(grid_level), pleft, 0,& |
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| 327 | ar(nzb,nys_l-nbgp_local,nxr_l+1), 1, type_yz_int(grid_level), pright, 0,& |
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| 328 | comm2d, status, ierr ) |
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| 329 | ! |
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| 330 | !-- Send right boundary, receive left one (synchronous) |
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| 331 | CALL MPI_SENDRECV( & |
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| 332 | ar(nzb,nys_l-nbgp_local,nxr_l+1-nbgp_local), 1, type_yz_int(grid_level),& |
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| 333 | pright, 1, & |
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| 334 | ar(nzb,nys_l-nbgp_local,nxl_l-nbgp_local), 1, type_yz_int(grid_level),& |
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| 335 | pleft, 1, & |
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| 336 | comm2d, status, ierr ) |
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| 337 | ENDIF |
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| 338 | |
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| 339 | |
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| 340 | IF ( pdims(2) == 1 ) THEN |
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| 341 | ! |
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| 342 | !-- One-dimensional decomposition along x, boundary values can be exchanged |
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| 343 | !-- within the PE memory |
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| 344 | IF ( bc_ns_cyc ) THEN |
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| 345 | ar(:,nys_l-nbgp_local:nys_l-1,:) = ar(:,nyn_l-nbgp_local+1:nyn_l,:) |
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| 346 | ar(:,nyn_l+1:nyn_l+nbgp_local,:) = ar(:,nys_l:nys_l+nbgp_local-1,:) |
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| 347 | ENDIF |
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| 348 | |
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| 349 | ELSE |
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| 350 | |
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| 351 | ! |
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| 352 | !-- Send front boundary, receive rear one (synchronous) |
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| 353 | CALL MPI_SENDRECV( & |
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| 354 | ar(nzb,nys_l,nxl_l-nbgp_local), 1, type_xz_int(grid_level), psouth, 0,& |
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| 355 | ar(nzb,nyn_l+1,nxl_l-nbgp_local), 1, type_xz_int(grid_level), pnorth, 0,& |
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| 356 | comm2d, status, ierr ) |
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| 357 | ! |
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| 358 | !-- Send rear boundary, receive front one (synchronous) |
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| 359 | CALL MPI_SENDRECV( ar(nzb,nyn_l-nbgp_local+1,nxl_l-nbgp_local), 1, & |
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| 360 | type_xz_int(grid_level), pnorth, 1, & |
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| 361 | ar(nzb,nys_l-nbgp_local,nxl_l-nbgp_local), 1, & |
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| 362 | type_xz_int(grid_level), psouth, 1, & |
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| 363 | comm2d, status, ierr ) |
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| 364 | |
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| 365 | ENDIF |
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| 366 | |
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| 367 | #else |
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| 368 | |
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| 369 | IF ( bc_lr_cyc ) THEN |
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| 370 | ar(:,:,nxl_l-nbgp_local:nxl_l-1) = ar(:,:,nxr_l-nbgp_local+1:nxr_l) |
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| 371 | ar(:,:,nxr_l+1:nxr_l+nbgp_local) = ar(:,:,nxl_l:nxl_l+nbgp_local-1) |
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| 372 | ENDIF |
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| 373 | |
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| 374 | IF ( bc_ns_cyc ) THEN |
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| 375 | ar(:,nys_l-nbgp_local:nys_l-1,:) = ar(:,nyn_l-nbgp_local+1:nyn_l,:) |
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| 376 | ar(:,nyn_l+1:nyn_l+nbgp_local,:) = ar(:,nys_l:nys_l+nbgp_local-1,:) |
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| 377 | ENDIF |
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| 378 | |
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| 379 | #endif |
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| 380 | |
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| 381 | |
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| 382 | END SUBROUTINE exchange_horiz_int |
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