Remove cutNode condition

cutNode condition seems to be irrelevant.

Passed STC:
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 24224 W: 6206 L: 5970 D: 12048
Ptnml(0-2): 69, 2818, 6122, 3014, 89
https://tests.stockfishchess.org/tests/view/65686910136acbc5735529ec

Passed LTC:
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 236538 W: 58624 L: 58622 D: 119292
Ptnml(0-2): 136, 26955, 64091, 26945, 142
https://tests.stockfishchess.org/tests/view/6568925a136acbc573552d8f

closes https://github.com/official-stockfish/Stockfish/pull/4901

Bench: 1244386

diff --git a/src/search.cpp b/src/search.cpp
index ba5ea2e54f9e3d7f92553016dfd503b11fa2cf12..b3ca8c9afe531582cd41811f8aeaf190bbb33c74 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1207,8 +1207,8 @@ moves_loop:  // When in check, search starts here
         // Step 18. Full-depth search when LMR is skipped
         else if (!PvNode || moveCount > 1)
         {
         // Step 18. Full-depth search when LMR is skipped
         else if (!PvNode || moveCount > 1)
         {

-            // Increase reduction for cut nodes without ttMove (~1 Elo)
-            if (!ttMove && cutNode)
+            // Increase reduction if ttMove is not present (~1 Elo)
+            if (!ttMove)

                 r += 2;
 
             // Note that if expected reduction is high, we reduce search depth by 1 here
                 r += 2;
 
             // Note that if expected reduction is high, we reduce search depth by 1 here