Reset EB Fab Type (AMReX-Codes#3552)

This is a follow-up on AMReX-Codes#3549. After extending EB data outside the
domain, we need to update the EB Fab type.

Src/EB/AMReX_EB2_Level.cpp

@@ -468,13 +468,7 @@ Level::fillEBCellFlag (FabArray<EBCellFlagFab>& cellflag, const Geometry& geom)
             }
 
             // fix type for each fab
-            fab.setType(FabType::undefined);
-            auto typ = fab.getType(bx);
-            fab.setType(typ);
-            for (int nshrink = 1; nshrink < ng; ++nshrink) {
-                const Box& b = amrex::grow(bx,-nshrink);
-                fab.getType(b);
-            }
+            fab.resetType(ng);
         }
     }
 }

Src/EB/AMReX_EBCellFlag.H

@@ -317,6 +317,11 @@ public:
      */
     FabType getType (const Box& bx) const noexcept;
 
+    /**
+     * \brief Reset FabType
+     */
+    void resetType (int ng);
+
     /**
      * \brief Returns the number of regular cells in the given Box.
      */

Src/EB/AMReX_EBCellFlag.cpp

@@ -128,6 +128,21 @@ EBCellFlagFab::getType (const Box& bx_in) const noexcept
     }
 }
 
+void
+EBCellFlagFab::resetType (int ng)
+{
+    this->setType(FabType::undefined);
+    m_typemap.clear();
+
+    Box const& bx = this->box();
+    auto typ = this->getType(bx);
+    this->setType(typ);
+    for (int nshrink = 1; nshrink < ng; ++nshrink) {
+        const Box& b = amrex::grow(bx,-nshrink);
+        this->getType(b);
+    }
+}
+
 int
 EBCellFlagFab::getNumRegularCells (const Box& bx_in) const noexcept
 {

Src/EB/AMReX_EBDataCollection.cpp

@@ -111,6 +111,11 @@ void EBDataCollection::extendDataOutsideDomain (IntVect const& level_ng)
 #pragma omp parallel if (Gpu::notInLaunchRegion())
 #endif
     for (MFIter mfi(*m_cellflags); mfi.isValid(); ++mfi) {
+        auto const current_type = (*m_cellflags)[mfi].getType();
+        // Because the default value for EBCellFlagFab is regular cell, we
+        // can skip a regular fab.
+        if (current_type == FabType::regular) { continue; }
+
         Box const& bx = mfi.fabbox();
         if (! level_domain.contains(bx)) {
             Box const& nbx = amrex::surroundingNodes(bx);
@@ -218,6 +223,12 @@ void EBDataCollection::extendDataOutsideDomain (IntVect const& level_ng)
                     });
                 }
             }
+
+            if ((*m_cellflags)[mfi].getType(mfi.validbox()) != FabType::singlevalued) {
+                // If it's already a cut fab in the valid region, the change in
+                // ghost cells will not change the fab types.
+                (*m_cellflags)[mfi].resetType(ngrow);
+            }
         }
     }
 }