further optimizations of EMCAL evalNExMax

Author: fjonasALICE

Detectors/EMCAL/base/include/EMCALBase/Geometry.h

@@ -435,7 +435,7 @@ class Geometry
   /// \param phiInModule index in phi direction in module
   /// \param etaInModule index in phi direction in module
   /// \return tuple with (row, column) of the cell, which is global numbering scheme
-  std::tuple<int, int> GetTopologicalRowColumn(int supermoduleID, int moduleID, int phiInModule, int etaInModule) const;
+  std::tuple<short, short> GetTopologicalRowColumn(int supermoduleID, int moduleID, int phiInModule, int etaInModule) const;
 
   /// \brief Adapt cell indices in supermodule to online indexing
   /// \param supermoduleID super module number of the channel/cell

Detectors/EMCAL/base/src/ClusterFactory.cxx

@@ -499,41 +499,44 @@ template <class InputType>
 void ClusterFactory<InputType>::evalNExMax(gsl::span<const int> inputsIndices, AnalysisCluster& clusterAnalysis) const
 {
   // Pre-compute cell indices and energies for all cells in cluster to avoid multiple expensive geometry lookups
-  struct CellInfo {
-    int row;
-    int column;
-    double energy;
-  };
-
-  std::vector<CellInfo> cellInfos;
-  cellInfos.reserve(inputsIndices.size());
+  const size_t n = inputsIndices.size();
+  std::vector<short> rows;
+  std::vector<short> columns;
+  std::vector<double> energies;
+  
+  rows.reserve(n);
+  columns.reserve(n);
+  energies.reserve(n);
 
   for (auto iInput : inputsIndices) {
     auto [nSupMod, nModule, nIphi, nIeta] = mGeomPtr->GetCellIndex(mInputsContainer[iInput].getTower());
 
     // get a nice topological indexing that is done in exactly the same way as used by the clusterizer
     // this way we can handle the shared cluster cases correctly
-    auto [row, column] = mGeomPtr->GetTopologicalRowColumn(nSupMod, nModule, nIphi, nIeta);
-    cellInfos.push_back({row, column, mInputsContainer[iInput].getEnergy()});
+    const auto [row, column] = mGeomPtr->GetTopologicalRowColumn(nSupMod, nModule, nIphi, nIeta);
+    
+    rows.push_back(row);
+    columns.push_back(column);
+    energies.push_back(mInputsContainer[iInput].getEnergy());
   }
 
   // Now find local maxima using pre-computed data
   int nExMax = 0;
-  for (size_t i = 0; i < cellInfos.size(); i++) {
+  for (size_t i = 0; i < n; i++) {    
     // this cell is assumed to be local maximum unless we find a higher energy cell in the neighborhood
     bool isExMax = true;
 
     // loop over all other cells in cluster
-    for (size_t j = 0; j < cellInfos.size(); j++) {
+    for (size_t j = 0; j < n; j++) {
       if (i == j)
         continue;
 
       // adjacent cell is any cell with adjacent phi or eta index
-      if (std::abs(cellInfos[i].row - cellInfos[j].row) <= 1 &&
-          std::abs(cellInfos[i].column - cellInfos[j].column) <= 1) {
+      if (std::abs(rows[i] - rows[j]) <= 1 &&
+          std::abs(columns[i] - columns[j]) <= 1) {
 
         // if there is a cell with higher energy than the current cell, it is not a local maximum
-        if (cellInfos[j].energy > cellInfos[i].energy) {
+        if (energies[j] > energies[i]) {
           isExMax = false;
           break;
         }

Detectors/EMCAL/base/src/Geometry.cxx

@@ -1103,7 +1103,7 @@ std::tuple<int, int> Geometry::GetCellPhiEtaIndexInSModule(int supermoduleID, in
   return std::make_tuple(phiInSupermodule, etaInSupermodule);
 }
 
-std::tuple<int, int> Geometry::GetTopologicalRowColumn(int supermoduleID, int moduleID, int phiInModule, int etaInModule) const
+std::tuple<short, short> Geometry::GetTopologicalRowColumn(int supermoduleID, int moduleID, int phiInModule, int etaInModule) const
 {
   auto [iphi, ieta] = GetCellPhiEtaIndexInSModule(supermoduleID, moduleID, phiInModule, etaInModule);
   int row = iphi;
@@ -1124,7 +1124,7 @@ std::tuple<int, int> Geometry::GetTopologicalRowColumn(int supermoduleID, int mo
     column += supermoduleID % 2 * (48 + 1);
   }
 
-  return std::make_tuple(row, column);
+  return std::make_tuple(static_cast<short>(row), static_cast<short>(column));
 }
 
 std::tuple<int, int> Geometry::ShiftOnlineToOfflineCellIndexes(Int_t supermoduleID, Int_t iphi, Int_t ieta) const