Simplify away the Reverse Move penalty

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 11d1df326bccf1a63238db6a2e3c01021a81b527..f2e11e35b520ba4438e478b2a03b7feaaff03a7a 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1756,10 +1756,6 @@ moves_loop: // When in check, search starts here
     thisThread->mainHistory[us][from_to(move)] << bonus;
     update_continuation_histories(ss, pos.moved_piece(move), to_sq(move), bonus);
 
-    // Penalty for reversed move in case of moved piece not being a pawn
-    if (type_of(pos.moved_piece(move)) != PAWN)
-        thisThread->mainHistory[us][from_to(reverse_move(move))] << -bonus;
-
     // Update countermove history
     if (is_ok((ss-1)->currentMove))
     {