-std::unique_ptr<CompatibilityGraph>
-Configuration::make_compatibility_graph_filtered_on(std::function<bool(UnfoldingEvent*)> pred) const
-{
- auto G = std::make_unique<CompatibilityGraph>();
-
- std::unordered_map<UnfoldingEvent*, std::unordered_set<CompatibilityGraphNode*>> discovered_conflicts;
- std::unordered_map<UnfoldingEvent*, CompatibilityGraphNode*> potential_placements;
- std::unordered_map<UnfoldingEvent*, int> direct_children_count;
-
- for (auto* e : get_topologically_sorted_events_of_reverse_graph()) {
-
- // 1. Figure out where to place `e` in `G`
-
- // Determine which nodes in the graph are in conflict
- // with this event. These nodes would have been added by child
- // events while iterating over the topological ordering of the reverse graph
- const auto known_conflicts = discovered_conflicts.find(e);
- const auto potential_placement = potential_placements.find(e);
- const auto potential_child_count = direct_children_count.find(e);
-
- const bool no_known_conflicts = known_conflicts == discovered_conflicts.end();
- const bool no_known_placement = potential_placement == potential_placements.end();
- const bool no_known_child_count = potential_child_count == direct_children_count.end();
-
- const auto e_conflicts =
- no_known_conflicts ? std::unordered_set<CompatibilityGraphNode*>() : std::move(known_conflicts->second);
- const auto e_child_count = no_known_child_count ? 0 : potential_child_count->second;
-
- CompatibilityGraphNode* e_placement = nullptr;
-
- // The justification is as follows:
- //
- // no_known_placement:
- // If nobody told us about a placement, we must either be a leaf event
- // OR be the cause of an event that itself has more than one cause.
- //
- // child_count >= 2:
- // If there are two or more events that this event causes,
- // then we certainly must be part of a different compatibility
- // graph node since
- const bool new_placement_required = no_known_placement || e_child_count >= 2;
-
- if (new_placement_required) {
- auto new_graph_node = std::make_unique<CompatibilityGraphNode>(e_conflicts, EventSet({e}));
- e_placement = new_graph_node.get();
- G->insert(std::move(new_graph_node));
- } else {
- xbt_assert(e_child_count == 1, "An event was informed by an immediate child of placement in "
- "the same compatibility graph node, yet the child did not inform "
- "the parent about its precense");
- // A child event told us this node can be in the
- // same compatibility node in the graph G. Add ourselves now
- e_placement = potential_placement->second;
- e_placement->add_event(e);
- }
-
- // 2. Update the children of `e`
-
- const EventSet& e_immediate_causes = e->get_immediate_causes();
- if (e_immediate_causes.size() == 1) {
- // If there is only a single ancestor, then it MAY BE in
- // the same "chain" of events as us. Note that the ancestor must
- // also have only a single child (see the note on `new_placement_required`)
- UnfoldingEvent* only_ancestor = *e_immediate_causes.begin();
- potential_placements[only_ancestor] = e_placement;
- }
-
- // Our ancestors conflict with everyone `e` does else PLUS `e` itself
- auto parent_conflicts = std::move(e_conflicts);
- parent_conflicts.insert(e_placement);
- for (auto* cause : e_immediate_causes) {
- direct_children_count[cause] += 1;
- discovered_conflicts[cause] = parent_conflicts;
- }
-
- // This event will only ever be seen once in the
- // topological ordering. Hence, its resources do not
- // need to be kept around
- discovered_conflicts.erase(e);
- direct_children_count.erase(e);
- potential_placements.erase(e);
- }
-
- return G;
-}
-