fixing query sending errors in DPT

Problem:
the query lenghts `lengths_to_distribute` were not set, thus it sent 0
length, and on the receiving side, the 0-length queries resulted in no
actual querying

Solution:
Set the `lengths_to_distribute` to the correct binned values

additionally: replaced GlobalIndex with size_t for local variables.
You need GlobalIndex only when sending. Locally for a size `env.size()`
sized array it just makes things slower without resulting in any memory
savings.

dpt/tree/distributed_patricia_trie.hpp

@@ -75,8 +75,8 @@ class distributed_patricia_trie {
  target_pes[i] = -1;
  }
  }
- std::vector<GlobalIndex> displ(env_.size(), 0);
- std::vector<GlobalIndex> displ_length(env_.size(), 0);
+ std::vector<size_t> displ(env_.size(), 0);
+ std::vector<size_t> displ_length(env_.size(), 0);
  for (int32_t i = 1; i < env_.size(); ++i) {
  displ[i] = displ[i - 1] + hist[i - 1];
  displ_length[i] = displ_length[i - 1] + hist_length[i - 1];
@@ -89,6 +89,7 @@ class distributed_patricia_trie {
  std::copy_n(queries[i].query, queries[i].length, 
  queries_to_distribute.begin() + displ_length[target_pes[i]]);
  displ_length[target_pes[i]] += queries[i].length;
+ lengths_to_distribute[displ[target_pes[i]]++] = queries[i].length;
  }
  }
  q_list rec_queries = manager_.template distribute_queries<Communication>(
@@ -117,8 +118,8 @@ class distributed_patricia_trie {
  target_pes[i] = std::make_pair(-1, -1);
  }
  }
- std::vector<GlobalIndex> displ(env_.size(), 0);
- std::vector<GlobalIndex> displ_length(env_.size(), 0);
+ std::vector<size_t> displ(env_.size(), 0);
+ std::vector<size_t> displ_length(env_.size(), 0);
  for (int32_t i = 1; i < env_.size(); ++i) {
  displ[i] = displ[i - 1] + hist[i - 1];
  displ_length[i] = displ_length[i - 1] + hist_length[i - 1];
@@ -131,10 +132,12 @@ class distributed_patricia_trie {
  std::copy_n(queries[i].query, queries[i].length, 
  queries_to_distribute.begin() + displ_length[target_pes[i].first]);
  displ_length[target_pes[i].first] += queries[i].length;
+ lengths_to_distribute[displ[target_pes[i].first]++] = queries[i].length;
  if (target_pes[i].first != target_pes[i].second) {
  std::copy_n(queries[i].query, queries[i].length, 
  queries_to_distribute.begin() + displ_length[target_pes[i].second]);
  displ_length[target_pes[i].second] += queries[i].length;
+ lengths_to_distribute[displ[target_pes[i].second]++] = queries[i].length;
  }
  }
  }
@@ -164,8 +167,8 @@ class distributed_patricia_trie {
  target_pes[i] = std::make_pair(-1, -1);
  }
  }
- std::vector<GlobalIndex> displ(env_.size(), 0);
- std::vector<GlobalIndex> displ_length(env_.size(), 0);
+ std::vector<size_t> displ(env_.size(), 0);
+ std::vector<size_t> displ_length(env_.size(), 0);
  for (int32_t i = 1; i < env_.size(); ++i) {
  displ[i] = displ[i - 1] + hist[i - 1];
  displ_length[i] = displ_length[i - 1] + hist_length[i - 1];
@@ -178,10 +181,12 @@ class distributed_patricia_trie {
  std::copy_n(queries[i].query, queries[i].length, 
  queries_to_distribute.begin() + displ_length[target_pes[i].first]);
  displ_length[target_pes[i].first] += queries[i].length;
+ lengths_to_distribute[displ[target_pes[i].first]++] = queries[i].length;
  if (target_pes[i].first != target_pes[i].second) {
  std::copy_n(queries[i].query, queries[i].length, 
  queries_to_distribute.begin() + displ_length[target_pes[i].second]);
  displ_length[target_pes[i].second] += queries[i].length;
+ lengths_to_distribute[displ[target_pes[i].second]++] = queries[i].length;
  }
  }
  }