Skip to content

Fix cycle detection in fill_uncovered_nodes second pass #4828

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
glennhickey merged 1 commit into from
Feb 13, 2026
+25 −25
Merged

Fix cycle detection in fill_uncovered_nodes second pass #4828

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
50 changes: 25 additions & 25 deletions src/augref.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -239,13 +239,32 @@ void AugRefCover::fill_uncovered_nodes(int64_t minimum_length) {
step_handle_t interval_start;
step_handle_t interval_end;
int64_t interval_length = 0;
vector<nid_t> interval_nodes; // track nodes in current interval
unordered_set<nid_t> interval_nodes; // track nodes in current interval for cycle detection

// Helper to close the current interval and add it if long enough
auto close_interval = [&]() {
if (in_interval) {
if (interval_length >= minimum_length) {
add_interval(this->augref_intervals, this->node_to_interval,
make_pair(interval_start, interval_end), true,
&this->interval_snarl_bounds, {0, 0});
for (nid_t nid : interval_nodes) {
uncovered_nodes.erase(nid);
}
}
in_interval = false;
}
};

graph->for_each_step_in_path(name_path.second, [&](step_handle_t step) {
nid_t node_id = graph->get_id(graph->get_handle_of_step(step));

if (uncovered_nodes.count(node_id)) {
// This node is uncovered
if (interval_nodes.count(node_id)) {
// This node is already in the current interval — close to avoid cycle,
// then start a new interval at this node (same logic as get_uncovered_intervals)
close_interval();
}
if (!in_interval) {
// Start a new interval
in_interval = true;
Expand All @@ -255,35 +274,16 @@ void AugRefCover::fill_uncovered_nodes(int64_t minimum_length) {
}
interval_end = graph->get_next_step(step);
interval_length += graph->get_length(graph->get_handle_of_step(step));
interval_nodes.push_back(node_id);
interval_nodes.insert(node_id);
} else {
// This node is already covered
if (in_interval) {
// Close the current interval
if (interval_length >= minimum_length) {
// Add the interval and mark nodes as covered
add_interval(this->augref_intervals, this->node_to_interval,
make_pair(interval_start, interval_end), true,
&this->interval_snarl_bounds, {0, 0});
for (nid_t nid : interval_nodes) {
uncovered_nodes.erase(nid);
}
}
in_interval = false;
}
// This node is already covered — close current interval
close_interval();
}
return true;
});

// Don't forget to close any interval at the end of the path
if (in_interval && interval_length >= minimum_length) {
add_interval(this->augref_intervals, this->node_to_interval,
make_pair(interval_start, interval_end), true,
&this->interval_snarl_bounds, {0, 0});
for (nid_t nid : interval_nodes) {
uncovered_nodes.erase(nid);
}
}
close_interval();
}

#ifdef debug
Expand Down
Loading