X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.cpp;h=cd8f5da675c966147d03354ebf841a2c3f8775ce;hp=c75526cc81b8b4989ca22fad6c54b3b5178a2c18;hb=d4a02b135deade2f3273716ccedb6f8a97316263;hpb=148490f04cbd21afd9b01431ee7c947ac0bf78a8

diff --git a/src/movepick.cpp b/src/movepick.cpp
index c75526cc..cd8f5da6 100644
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -70,7 +70,7 @@ namespace {
 /// search captures, promotions and some checks) and about how important good
 /// move ordering is at the current node.
 
-MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h, const CountermovesStats& cm,
+MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h, Move* cm,
                        Search::Stack* s, Value beta) : pos(p), history(h), depth(d) {
 
   assert(d > DEPTH_ZERO);
@@ -78,6 +78,7 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats&
   captureThreshold = 0;
   cur = end = moves;
   endBadCaptures = moves + MAX_MOVES - 1;
+  countermoves = cm;
   ss = s;
 
   if (p.checkers())
@@ -87,17 +88,12 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats&
   {
       phase = MAIN_SEARCH;
 
-      killers[0].move = ss->killers[0];
-      killers[1].move = ss->killers[1];
-      Square prevSq = to_sq((ss-1)->currentMove);
-      killers[2].move = cm[pos.piece_on(prevSq)][prevSq];
-
       // Consider sligtly negative captures as good if at low depth and far from beta
-      if (ss && ss->staticEval < beta - PawnValueMg && d < 3 * ONE_PLY)
+      if (ss->staticEval < beta - PawnValueMg && d < 3 * ONE_PLY)
           captureThreshold = -PawnValueMg;
 
       // Consider negative captures as good if still enough to reach beta
-      else if (ss && ss->staticEval > beta)
+      else if (ss->staticEval > beta)
           captureThreshold = beta - ss->staticEval;
   }
 
@@ -239,7 +235,20 @@ void MovePicker::generate_next() {
 
   case KILLERS_S1:
       cur = killers;
-      end = cur + 3 - (killers[2].move == killers[0].move || killers[2].move == killers[1].move);
+      end = cur + 2;
+
+      killers[0].move = ss->killers[0];
+      killers[1].move = ss->killers[1];
+      killers[2].move = killers[3].move = MOVE_NONE;
+
+      // Be sure countermoves are different from killers
+      for (int i = 0; i < 2; i++)
+          if (countermoves[i] != cur->move && countermoves[i] != (cur+1)->move)
+              (end++)->move = countermoves[i];
+
+      if (countermoves[1] && countermoves[1] == countermoves[0]) // Due to SMP races
+          killers[3].move = MOVE_NONE;
+
       return;
 
   case QUIETS_1_S1:
@@ -332,7 +341,8 @@ Move MovePicker::next_move<false>() {
           if (   move != ttMove
               && move != killers[0].move
               && move != killers[1].move
-              && move != killers[2].move)
+              && move != killers[2].move
+              && move != killers[3].move)
               return move;
           break;