Tuned nullmove search

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index b0bcc57a44ee05f8f71fe2205d187f25622613fb..25a7cf44044780275be61204b56b0035fcf4250d 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -825,10 +825,10 @@ namespace {
     // Step 9. Null move search with verification search (~40 Elo)
     if (   !PvNode
         && (ss-1)->currentMove != MOVE_NULL
-        && (ss-1)->statScore < 23405
+        && (ss-1)->statScore < 23397
         &&  eval >= beta
         &&  eval >= ss->staticEval
-        &&  ss->staticEval >= beta - 32 * depth + 317 - improving * 30
+        &&  ss->staticEval >= beta - 32 * depth + 292 - improving * 30
         && !excludedMove
         &&  pos.non_pawn_material(us)
         && (ss->ply >= thisThread->nmpMinPly || us != thisThread->nmpColor))
@@ -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)