Remove Capture history pruning

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 8a4db35185921776e4288e02e83c8744c2c35db7..988166df9bb1682a6094654853c7f7c5b77239c3 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1031,10 +1031,14 @@ moves_loop: // When in check, search starts here
           if (   captureOrPromotion
               || givesCheck)
           {
-              // Capture history based pruning when the move doesn't give check
-              if (   !givesCheck
-                  && lmrDepth < 1
-                  && captureHistory[movedPiece][to_sq(move)][type_of(pos.piece_on(to_sq(move)))] < 0)
+              // Futility pruning for captures
+              if (   !pos.empty(to_sq(move))
+                  && !givesCheck
+                  && !PvNode
+                  && lmrDepth < 6
+                  && !ss->inCheck
+                  && ss->staticEval + 342 + 238 * lmrDepth + PieceValue[EG][pos.piece_on(to_sq(move))] 
+                   + captureHistory[movedPiece][to_sq(move)][type_of(pos.piece_on(to_sq(move)))] / 8 < alpha)
                   continue;
 
               // SEE based pruning
@@ -1113,12 +1117,6 @@ moves_loop: // When in check, search starts here
               extension = -2;
       }
 
-      // Capture extensions for PvNodes and cutNodes
-      else if (   (PvNode || cutNode)
-               && captureOrPromotion
-               && moveCount != 1)
-          extension = 1;
-
       // Check extensions
       else if (   givesCheck
                && depth > 6