Tweak futility pruning

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index b0bcc57a44ee05f8f71fe2205d187f25622613fb..57316d85613b955cc14d3daedaffabc0887bc62f 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1003,7 +1003,11 @@ moves_loop: // When in check, search starts from here
               // Futility pruning: parent node (~2 Elo)
               if (   lmrDepth < 6
                   && !inCheck
-                  && ss->staticEval + 255 + 182 * lmrDepth <= alpha)
+                  && ss->staticEval + 255 + 182 * lmrDepth <= alpha
+                  &&  thisThread->mainHistory[us][from_to(move)]
+                    + (*contHist[0])[movedPiece][to_sq(move)]
+                    + (*contHist[1])[movedPiece][to_sq(move)]
+                    + (*contHist[3])[movedPiece][to_sq(move)] < 30000)
                   continue;
 
               // Prune moves with negative SEE (~10 Elo)