Fix potential crash (#103)

avoid overwriting NodeData for tablebase nodes
delete inCheck from Node

engine/src/agents/mctsagent.cpp

@@ -166,11 +166,10 @@ shared_ptr<Node> MCTSAgent::get_root_node_from_tree(StateObj *state)
 void MCTSAgent::create_new_root_node(StateObj* state)
 {
     info_string("create new tree");
-    // TODO: Make sure that "inCheck=False" does not cause issues
 #ifdef MCTS_STORE_STATES
-    rootNode = make_shared<Node>(state->clone(), false, searchSettings);
+    rootNode = make_shared<Node>(state->clone(), searchSettings);
 #else
-    rootNode = make_shared<Node>(state, false, searchSettings);
+    rootNode = make_shared<Node>(state, searchSettings);
 #endif
 #ifdef SEARCH_UCT
     unique_ptr<StateObj> newState = unique_ptr<StateObj>(state->clone());

engine/src/constants.h

@@ -53,7 +53,7 @@ const string engineName = "MultiAra";
 const string engineName = "ClassicAra";
 #endif
 
-const string engineVersion = "0.9.2.post1-Dev";
+const string engineVersion = "0.9.2.post2";
 const string engineAuthors = "Johannes Czech, Moritz Willig, Alena Beyer et al.";
 
 #define LOSS_VALUE -1

engine/src/node.cpp

@@ -79,7 +79,7 @@ void Node::set_auxiliary_outputs(const float* auxiliaryOutputs)
 }
 #endif
 
-Node::Node(StateObj* state, bool inCheck, const SearchSettings* searchSettings):
+Node::Node(StateObj* state, const SearchSettings* searchSettings):
     legalActions(state->legal_actions()),
     key(state->hash_key()),
     valueSum(0),
@@ -96,7 +96,7 @@ Node::Node(StateObj* state, bool inCheck, const SearchSettings* searchSettings):
     sorted(false)
 {
     // specify the number of direct child nodes of this node
-    check_for_terminal(state, inCheck);
+    check_for_terminal(state);
 #ifdef MCTS_TB_SUPPORT
     if (searchSettings->useTablebase && !isTerminal) {
         check_for_tablebase_wdl(state);
@@ -556,7 +556,9 @@ size_t Node::get_number_child_nodes() const
 void Node::prepare_node_for_visits()
 {
     sort_moves_by_probabilities();
-    init_node_data();
+    if (d == nullptr) {  // mark_tablebase() initializes the NodeData
+        init_node_data();
+    }
 #ifdef MCTS_STORE_STATES
     state->prepare_action();
 #endif
@@ -751,7 +753,7 @@ void Node::mark_as_terminal()
     d->noVisitIdx = 0;
 }
 
-void Node::check_for_terminal(StateObj* pos, bool inCheck)
+void Node::check_for_terminal(StateObj* pos)
 {
     float customValue;
     TerminalType terminalType = pos->is_terminal(get_number_child_nodes(), customValue);
@@ -802,7 +804,6 @@ void Node::check_for_tablebase_wdl(StateObj* state)
 void Node::mark_as_tablebase()
 {
     init_node_data();
-    fully_expand_node();
     isTablebase = true;
 }
 #endif

engine/src/node.h

@@ -85,12 +85,10 @@ class Node
 public:
     /**
      * @brief Node Primary constructor which is used when expanding a node during search
-     * @param parentNode Pointer to parent node
-     * @param move Move which led to current board state
+     * @param State Corresponding state object
      * @param searchSettings Pointer to the searchSettings
      */
     Node(StateObj *state,
-         bool inCheck,
          const SearchSettings* searchSettings);
 
     /**
@@ -477,9 +475,8 @@ class Node
     /**
      * @brief check_for_terminal Checks if the given board position is a terminal node and updates isTerminal
      * @param state Current board position for this node
-     * @param inCheck Boolean indicating if the king is in check
      */
-    void check_for_terminal(StateObj* state, bool inCheck);
+    void check_for_terminal(StateObj* state);
 
 #ifdef MCTS_TB_SUPPORT
     /**

engine/src/searchthread.cpp

@@ -80,7 +80,7 @@ void SearchThread::set_is_running(bool value)
     isRunning = value;
 }
 
-NodeBackup SearchThread::add_new_node_to_tree(StateObj* newState, Node* parentNode, ChildIdx childIdx, bool inCheck)
+NodeBackup SearchThread::add_new_node_to_tree(StateObj* newState, Node* parentNode, ChildIdx childIdx)
 {
     if(searchSettings->useMCGS) {
         mapWithMutex->mtx.lock();
@@ -107,7 +107,7 @@ NodeBackup SearchThread::add_new_node_to_tree(StateObj* newState, Node* parentNo
         mapWithMutex->mtx.unlock();
     }
     assert(parentNode != nullptr);
-    shared_ptr<Node> newNode = make_shared<Node>(newState, inCheck, searchSettings);
+    shared_ptr<Node> newNode = make_shared<Node>(newState, searchSettings);
     // connect the Node to the parent
     parentNode->add_new_child_node(newNode, childIdx);
     return NODE_NEW_NODE;
@@ -210,13 +210,12 @@ Node* SearchThread::get_new_child_to_evaluate(ChildIdx& childIdx, NodeDescriptio
                 newState->do_action(action);
             }
 #endif
-            const bool inCheck = newState->gives_check(currentNode->get_action(childIdx));
             newState->do_action(currentNode->get_action(childIdx));
             currentNode->increment_no_visit_idx();
 #ifdef MCTS_STORE_STATES
-            description.type = add_new_node_to_tree(newState, currentNode, childIdx, inCheck);
+            description.type = add_new_node_to_tree(newState, currentNode, childIdx);
 #else
-            description.type = add_new_node_to_tree(newState.get(), currentNode, childIdx, inCheck);
+            description.type = add_new_node_to_tree(newState.get(), currentNode, childIdx);
 #endif
             currentNode->unlock();
 
@@ -306,6 +305,10 @@ void SearchThread::set_nn_results_to_child_nodes()
 {
     size_t batchIdx = 0;
     for (auto node: *newNodes) {
+        if (node == nullptr) {
+            info_string("nullptr newNode");
+            continue;
+        }
         if (!node->is_terminal()) {
             fill_nn_results(batchIdx, net->is_policy_map(), valueOutputs, probOutputs, auxiliaryOutputs, node, tbHits, newNodeSideToMove->get_element(batchIdx), searchSettings, rootNode->is_tablebase());
         }
@@ -417,6 +420,9 @@ void run_search_thread(SearchThread *t)
 void SearchThread::backup_values(FixedVector<Node*>& nodes, vector<Trajectory>& trajectories) {
     for (size_t idx = 0; idx < nodes.size(); ++idx) {
         Node* node = nodes.get_element(idx);
+        if (node == nullptr) {
+            continue;
+        }
 #ifdef MCTS_TB_SUPPORT
         const bool solveForTerminal = searchSettings->mctsSolver && node->is_tablebase();
         backup_value<false>(node->get_value(), searchSettings->virtualLoss, trajectories[idx], solveForTerminal);

engine/src/searchthread.h

@@ -146,7 +146,7 @@ class SearchThread : NeuralNetAPIUser
      * @param inCheck Defines if the current position sets a player in check
      * @return Returns NODE_TRANSPOSITION if a tranpsosition node was added and NODE_NEW_NODE otherwise
      */
-    NodeBackup add_new_node_to_tree(StateObj* newPos, Node* parentNode, ChildIdx childIdx, bool inCheck);
+    NodeBackup add_new_node_to_tree(StateObj* newPos, Node* parentNode, ChildIdx childIdx);
 
     /**
      * @brief reset_tb_hits Sets the number of table hits to 0