Double extend search even more via LMR

locutus2 · snicolet · commit 8557f35aa5c0 · 2021-10-24T22:13:47.000+02:00
Allow now for the first five moves a two plies deeper LMR search. STC: LLR: 2.96 (-2.94,2.94) <-2.50,0.50> Total: 99608 W: 25143 L: 25115 D: 49350 Ptnml(0-2): 291, 11444, 26328, 11428, 313 https://tests.stockfishchess.org/tests/view/61718c9438cb9784038af8d7 LTC: LLR: 2.95 (-2.94,2.94) <-2.50,0.50> Total: 52064 W: 13234 L: 13145 D: 25685 Ptnml(0-2): 35, 5431, 15014, 5514, 38 https://tests.stockfishchess.org/tests/view/6171e13e38cb9784038af928 closes #3760 Bench: 7222293
diff --git a/src/search.cpp b/src/search.cpp
@@ -1210,8 +1210,7 @@ namespace {
           // are really negative and movecount is low, we allow this move to be searched
           // deeper than the first move (this may lead to hidden double extensions).
           int deeper =   r >= -1             ? 0
-                       : moveCount <= 3      ? 2
-                       : moveCount <= 5      ? 1
+                       : moveCount <= 5      ? 2
                        : PvNode && depth > 6 ? 1
                        :                       0;
 
