+
+// Reuse mark pools if one already exists.
+MarkPool *get_mark_pool(map<pair<int, int>, MarkPool *> *mark_pools, int from, int to)
+{
+ pair<int, int> mark_range(from, to);
+ if (mark_pools->count(mark_range) != 0) {
+ return (*mark_pools)[mark_range];
+ }
+
+ // Check if we're overlapping some other mark pool.
+ for (map<pair<int, int>, MarkPool *>::const_iterator mp_it = mark_pools->begin();
+ mp_it != mark_pools->end();
+ ++mp_it) {
+ int other_from = mp_it->first.first;
+ int other_to = mp_it->first.second;
+ if ((from >= other_from && from < other_to) ||
+ (to >= other_from && to < other_to)) {
+ fprintf(stderr, "WARNING: Mark pool %d-%d partially overlaps with %d-%d, you may get duplicate marks.\n",
+ from, to, other_from, other_to);
+ fprintf(stderr, " Mark pools must either be completely disjunct, or completely overlapping.\n");
+ }
+ }
+
+ MarkPool *mark_pool = new MarkPool(from, to);
+ mark_pools->insert(make_pair(mark_range, mark_pool));
+ return mark_pool;
+}