Merge branch 'mark-petersen/ocn/fix-intel-opt-decomp' into next (PR #…

…5356)

Move bottomDepthEdge calculation to single loop over all edges

After #5195 was merged, the MPAS-Ocean standalone test
ocean/baroclinic_channel/10km/decomp_test failed to match between 4 and
8 partitions, but only for intel optimized. All compass nightly suite
tests passed for gnu debug, gnu optimized, intel debug.

This PR solves the problem by merging the computation of bottomDepthEdge
into a single edge loop. Previously it was split into two loops,
1:nEdgesOwned (with many other calculations) and another from
nEdgesOwned+1:nEdgesArray(4). The intel optimized compiler must have
changed order-of-operations in these two loops for different partitions.

Fixes #5219
[BFB]

components/mpas-ocean/src/mode_forward/mpas_ocn_time_integration_split.F

@@ -173,8 +173,6 @@ subroutine ocn_time_integrator_split(domain, dt)!{{{
          edgeHaloComputeCounter, &! halo counters to reduce
          cellHaloComputeCounter   ! halo updates during cycling
 
-      integer, dimension(:), pointer :: nEdgesArray
-
       real (kind=RKIND) :: &
          normalThicknessFluxSum, &! sum of thickness flux in column
          thicknessSum,     &! sum of thicknesses in column
@@ -385,8 +383,6 @@ subroutine ocn_time_integrator_split(domain, dt)!{{{
 
       call mpas_pool_get_array(tracersPool, 'activeTracers', activeTracersNew, 2)
 
-      call mpas_pool_get_dimension(meshPool,'nEdgesArray', nEdgesArray)
-
       allocate(bottomDepthEdge(nEdgesAll+1))
 
       if (config_transport_tests_flow_id > 0) then
@@ -775,8 +771,6 @@ subroutine ocn_time_integrator_split(domain, dt)!{{{
                enddo
                barotropicForcing(iEdge) = splitFact* &
                               normalThicknessFluxSum/thicknessSum/dt
-               bottomDepthEdge(iEdge) = thicknessSum &
-                  - 0.5_RKIND*(sshNew(cell1) + sshNew(cell2))
 
                do k = minLevelEdgeBot(iEdge), maxLevelEdgeTop(iEdge)
                   ! These two steps are together here:
@@ -798,7 +792,7 @@ subroutine ocn_time_integrator_split(domain, dt)!{{{
             !$omp parallel
             !$omp do schedule(runtime) &
             !$omp private(cell1, cell2, k, thicknessSum)
-            do iEdge = nEdgesOwned+1, nEdgesArray(4)
+            do iEdge = 1, nEdgesHalo(config_num_halos+1)
                cell1 = cellsOnEdge(1,iEdge)
                cell2 = cellsOnEdge(2,iEdge)
                thicknessSum = layerThickEdgeFlux(minLevelEdgeBot(iEdge),iEdge)