From c387bde956370a209a278160ced4c488af10d1ad Mon Sep 17 00:00:00 2001
From: Sterling Harper <smharper@mit.edu>
Date: Fri, 7 Sep 2018 17:26:57 -0400
Subject: [PATCH] Add basic C++ TallyFilterMatch class

---
 CMakeLists.txt                        |  1 +
 include/openmc/tallies/tally_filter.h | 34 +++++++++++++++++++++++++++
 src/simulation.F90                    | 19 ++++++++++++++-
 src/simulation.cpp                    | 26 +++++++++++++++++++-
 src/tallies/tally_filter_header.F90   | 11 +++++++++
 5 files changed, 89 insertions(+), 2 deletions(-)
 create mode 100644 include/openmc/tallies/tally_filter.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 23a6176a8..31df21d82 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -417,6 +417,7 @@ add_library(libopenmc SHARED
   src/state_point.cpp
   src/string_functions.cpp
   src/surface.cpp
+  src/tallies/tally_filter.cpp
   src/thermal.cpp
   src/xml_interface.cpp
   src/xsdata.cpp)
diff --git a/include/openmc/tallies/tally_filter.h b/include/openmc/tallies/tally_filter.h
new file mode 100644
index 000000000..85b6f8c72
--- /dev/null
+++ b/include/openmc/tallies/tally_filter.h
@@ -0,0 +1,34 @@
+#ifndef OPENMC_TALLY_FILTER_H
+#define OPENMC_TALLY_FILTER_H
+
+#include <cstdint>
+#include <vector>
+
+
+namespace openmc {
+
+//==============================================================================
+// Global variables
+//==============================================================================
+
+extern "C" int32_t n_filters;
+
+class TallyFilterMatch;
+extern std::vector<TallyFilterMatch> filter_matches;
+#pragma omp threadprivate(filter_matches)
+
+//==============================================================================
+//! Stores bins and weights for filtered tally events
+//==============================================================================
+
+class TallyFilterMatch
+{
+public:
+  int i_bin;
+  std::vector<int> bins;
+  std::vector<double> weights;
+  bool bins_present;
+};
+
+} // namespace openmc
+#endif // OPENMC_TALLY_FILTER
diff --git a/src/simulation.F90 b/src/simulation.F90
index df6bf13ba..9fa2b290d 100644
--- a/src/simulation.F90
+++ b/src/simulation.F90
@@ -36,7 +36,7 @@ module simulation
   use tally,           only: accumulate_tallies, setup_active_tallies, &
                              init_tally_routines
   use tally_header
-  use tally_filter_header, only: filter_matches, n_filters
+  use tally_filter_header, only: filter_matches, n_filters, filter_match_pointer
   use tally_derivative_header, only: tally_derivs
   use timer_header
   use trigger,         only: check_triggers
@@ -420,6 +420,11 @@ contains
 
     integer :: i
 
+    interface
+      subroutine openmc_simulation_init_c() bind(C)
+      end subroutine openmc_simulation_init_c
+    end interface
+
     err = 0
 
     ! Skip if simulation has already been initialized
@@ -453,6 +458,9 @@ contains
 
     ! Allocate array for matching filter bins
     allocate(filter_matches(n_filters))
+    do i = 1, n_filters
+      filter_matches(i) % ptr = filter_match_pointer(i - 1)
+    end do
 !$omp end parallel
 
     ! Reset global variables -- this is done before loading state point (as that
@@ -493,6 +501,8 @@ contains
       end if
     end if
 
+    call openmc_simulation_init_c()
+
     ! Set flag indicating initialization is done
     simulation_initialized = .true.
 
@@ -520,6 +530,11 @@ contains
 #endif
 #endif
 
+    interface
+      subroutine openmc_simulation_finalize_c() bind(C)
+      end subroutine openmc_simulation_finalize_c
+    end interface
+
     err = 0
 
     ! Skip if simulation was never run
@@ -590,6 +605,8 @@ contains
       end do
     end if
 
+    call openmc_simulation_finalize_c()
+
     ! Stop timers and show timing statistics
     call time_finalize%stop()
     call time_total%stop()
diff --git a/src/simulation.cpp b/src/simulation.cpp
index e1dd0ac93..e9cb971cf 100644
--- a/src/simulation.cpp
+++ b/src/simulation.cpp
@@ -1,10 +1,12 @@
 #include "openmc/capi.h"
+#include "openmc/tallies/tally_filter.h"
 
 // OPENMC_RUN encompasses all the main logic where iterations are performed
 // over the batches, generations, and histories in a fixed source or k-eigenvalue
 // calculation.
 
-int openmc_run() {
+int openmc_run()
+{
   openmc_simulation_init();
 
   int err = 0;
@@ -16,3 +18,25 @@ int openmc_run() {
   openmc_simulation_finalize();
   return err;
 }
+
+namespace openmc {
+
+extern "C" void
+openmc_simulation_init_c()
+{
+  #pragma omp parallel
+  {
+    filter_matches.resize(n_filters);
+  }
+}
+
+extern "C" void
+openmc_simulation_finalize_c()
+{
+  #pragma omp parallel
+  {
+    filter_matches.clear();
+  }
+}
+
+} // namespace openmc
diff --git a/src/tallies/tally_filter_header.F90 b/src/tallies/tally_filter_header.F90
index 57b6798bb..38de7a5ad 100644
--- a/src/tallies/tally_filter_header.F90
+++ b/src/tallies/tally_filter_header.F90
@@ -20,12 +20,23 @@ module tally_filter_header
   public :: openmc_filter_set_id
   public :: openmc_get_filter_index
   public :: openmc_get_filter_next_id
+  public :: filter_match_pointer
+
+  interface
+    function filter_match_pointer(indx) bind(C) result(ptr)
+      import C_PTR, C_INT
+      integer(C_INT), intent(in), value :: indx
+      type(C_PTR)                       :: ptr
+    end function filter_match_pointer
+  end interface
 
 !===============================================================================
 ! TALLYFILTERMATCH stores every valid bin and weight for a filter
 !===============================================================================
 
   type, public :: TallyFilterMatch
+    type(C_PTR) :: ptr
+
     ! Index of the bin and weight being used in the current filter combination
     integer          :: i_bin
     type(VectorInt)  :: bins_