Never clear stats

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index f0c1bdd978e14fdc661c2a4041bb220fce343055..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"]);
@@ -599,7 +595,7 @@ namespace {
         ss->currentMove = ttMove; // Can be MOVE_NONE
 
         // If ttMove is quiet, update killers, history, counter move on TT hit
-        if (ttValue >= beta && ttMove && !pos.capture_or_promotion(ttMove) && !inCheck)
+        if (ttValue >= beta && ttMove && !pos.capture_or_promotion(ttMove))
             update_stats(pos, ss, ttMove, depth, nullptr, 0);
 
         return ttValue;
@@ -945,8 +941,6 @@ moves_loop: // When in check and at SpNode search starts from here
       }
 
       ss->currentMove = move;
-      if (!SpNode && !captureOrPromotion && quietCount < 64)
-          quietsSearched[quietCount++] = move;
 
       // Step 14. Make the move
       pos.do_move(move, st, givesCheck);
@@ -962,10 +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)
@@ -1101,6 +1094,9 @@ moves_loop: // When in check and at SpNode search starts from here
           }
       }
 
+      if (!SpNode && !captureOrPromotion && move != bestMove && quietCount < 64)
+          quietsSearched[quietCount++] = move;
+
       // Step 19. Check for splitting the search
       if (   !SpNode
           &&  Threads.size() >= 2
@@ -1144,8 +1140,8 @@ 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 (bestValue >= beta && !pos.capture_or_promotion(bestMove) && !inCheck)
-        update_stats(pos, ss, bestMove, depth, quietsSearched, quietCount - 1);
+    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),
               bestValue >= beta ? BOUND_LOWER :
@@ -1302,8 +1298,7 @@ moves_loop: // When in check and at SpNode search starts from here
       // Detect non-capture evasions that are candidates to be pruned
       evasionPrunable =    InCheck
                        &&  bestValue > VALUE_MATED_IN_MAX_PLY
-                       && !pos.capture(move)
-                       && !pos.can_castle(pos.side_to_move());
+                       && !pos.capture(move);
 
       // Don't search moves with negative SEE values
       if (  (!InCheck || evasionPrunable)
@@ -1403,10 +1398,12 @@ moves_loop: // When in check and at SpNode search starts from here
     *pv = MOVE_NONE;
   }
 
-  // update_stats() updates killers, history and countermoves stats after a fail-high
-  // of a quiet 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)
     {