no cut node reduction for killer moves.
authorcandirufish <38038147+candirufish@users.noreply.github.com>
Thu, 1 Jul 2021 17:51:41 +0000 (19:51 +0200)
committerJoost VandeVondele <Joost.VandeVondele@gmail.com>
Sat, 3 Jul 2021 07:44:05 +0000 (09:44 +0200)
stc:
LLR: 2.95 (-2.94,2.94) <-0.50,2.50>
Total: 44344 W: 3474 L: 3294 D: 37576
Ptnml(0-2): 117, 2710, 16338, 2890, 117
https://tests.stockfishchess.org/tests/view/60d8ea673beab81350ac9eb8

ltc:
LLR: 2.93 (-2.94,2.94) <0.50,3.50>
Total: 82600 W: 2638 L: 2441 D: 77521
Ptnml(0-2): 38, 2147, 36749, 2312, 54
https://tests.stockfishchess.org/tests/view/60d9048f3beab81350ac9eed

closes https://github.com/official-stockfish/Stockfish/pull/3600

Bench: 5160239

src/search.cpp

index a413bd3814fec6daa13b08ed3bbe9db6182158b3..5974cba731ef04a6c71885216e92818392aa5c8d 100644 (file)
@@ -1157,8 +1157,8 @@ moves_loop: // When in check, search starts from here
               r--;
 
           // Increase reduction for cut nodes (~3 Elo)
-          if (cutNode)
-              r += 1 + !captureOrPromotion;
+          if (cutNode && move != ss->killers[0])
+              r += 2;
 
           if (!captureOrPromotion)
           {