Never clear stats

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 8f074ca6923c6c21e68ceef098dd55dd5f63fa76..9c7190bed0cacb99e7d813df7196e205cb23bac8 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -66,14 +66,14 @@ namespace {
   enum NodeType { Root, PV, NonPV };
 
   // Razoring and futility margin based on depth
-  inline Value razor_margin(Depth d) { return Value(512 + 32 * d); }
-  inline Value futility_margin(Depth d) { return Value(200 * d); }
+  Value razor_margin(Depth d) { return Value(512 + 32 * d); }
+  Value futility_margin(Depth d) { return Value(200 * d); }
 
   // Futility and reductions lookup tables, initialized at startup
   int FutilityMoveCounts[2][16];  // [improving][depth]
   Depth Reductions[2][2][64][64]; // [pv][improving][depth][moveNumber]
 
-  template <bool PvNode> inline Depth reduction(bool i, Depth d, int mn) {
+  template <bool PvNode> Depth reduction(bool i, Depth d, int mn) {
     return Reductions[PvNode][i][std::min(d, 63 * ONE_PLY)][std::min(mn, 63)];
   }
 
@@ -339,10 +339,6 @@ namespace {
     beta = VALUE_INFINITE;
 
     TT.new_search();
-    History.clear();
-    CounterMovesHistory.clear();
-    Gains.clear();
-    Countermoves.clear();
 
     size_t multiPV = Options["MultiPV"];
     Skill skill(Options["Skill Level"]);
@@ -960,10 +956,9 @@ moves_loop: // When in check and at SpNode search starts from here
           ss->reduction = reduction<PvNode>(improving, depth, moveCount);
 
           if (   (!PvNode && cutNode)
-              ||  History[pos.piece_on(to_sq(move))][to_sq(move)] < VALUE_ZERO
-              || (  History[pos.piece_on(to_sq(move))][to_sq(move)]
-                  + CounterMovesHistory[pos.piece_on(prevMoveSq)][prevMoveSq]
-                                       [pos.piece_on(to_sq(move))][to_sq(move)] < VALUE_ZERO))
+              || (   History[pos.piece_on(to_sq(move))][to_sq(move)] < VALUE_ZERO
+                  && CounterMovesHistory[pos.piece_on(prevMoveSq)][prevMoveSq]
+                                        [pos.piece_on(to_sq(move))][to_sq(move)] <= VALUE_ZERO))
               ss->reduction += ONE_PLY;
 
           if (move == countermove)
@@ -1068,7 +1063,6 @@ moves_loop: // When in check and at SpNode search starts from here
               rm.score = -VALUE_INFINITE;
       }
 
-      bool newBestMove = false;
       if (value > bestValue)
       {
           bestValue = SpNode ? splitPoint->bestValue = value : value;
@@ -1081,7 +1075,6 @@ moves_loop: // When in check and at SpNode search starts from here
                   && (move != EasyMove.get(pos.key()) || moveCount > 1))
                   EasyMove.clear();
 
-              newBestMove = true;
               bestMove = SpNode ? splitPoint->bestMove = move : move;
 
               if (PvNode && !RootNode) // Update pv even in fail-high case
@@ -1101,7 +1094,7 @@ moves_loop: // When in check and at SpNode search starts from here
           }
       }
 
-      if (!SpNode && !captureOrPromotion && !newBestMove && quietCount < 64)
+      if (!SpNode && !captureOrPromotion && move != bestMove && quietCount < 64)
           quietsSearched[quietCount++] = move;
 
       // Step 19. Check for splitting the search
@@ -1147,7 +1140,7 @@ moves_loop: // When in check and at SpNode search starts from here
                    :     inCheck ? mated_in(ss->ply) : DrawValue[pos.side_to_move()];
 
     // Quiet best move: update killers, history and countermoves
-    else if (bestMove != MOVE_NONE && !pos.capture_or_promotion(bestMove))
+    else if (bestMove && !pos.capture_or_promotion(bestMove))
         update_stats(pos, ss, bestMove, depth, quietsSearched, quietCount);
 
     tte->save(posKey, value_to_tt(bestValue, ss->ply),
@@ -1405,9 +1398,12 @@ moves_loop: // When in check and at SpNode search starts from here
     *pv = MOVE_NONE;
   }
 
-  // update_stats() updates killers, history, countermove history and countermoves stats for a quiet best move.
 
-  void update_stats(const Position& pos, Stack* ss, Move move, Depth depth, Move* quiets, int quietsCnt) {
+  // update_stats() updates killers, history, countermove history and
+  // countermoves stats for a quiet best move.
+
+  void update_stats(const Position& pos, Stack* ss, Move move,
+                    Depth depth, Move* quiets, int quietsCnt) {
 
     if (ss->killers[0] != move)
     {