Simplify evaluate condition on search

Remove condition for MOVE_NULL on search.

STC:
LLR: 2.94 (-2.94,2.94) <-2.50,0.50>
Total: 47544 W: 11968 L: 11864 D: 23712
Ptnml(0-2): 150, 5535, 12318, 5599, 170
https://tests.stockfishchess.org/tests/view/616e37143799eb91f1f071ee

LTC:
LLR: 2.93 (-2.94,2.94) <-2.50,0.50>
Total: 67472 W: 16938 L: 16870 D: 33664
Ptnml(0-2): 49, 7119, 19331, 7189, 48
https://tests.stockfishchess.org/tests/view/616e3fab3799eb91f1f071f1

closes https://github.com/official-stockfish/Stockfish/pull/3746

bench: 5255771

diff --git a/src/search.cpp b/src/search.cpp
index 55a689567b4029cdb6c5f13c6f0b27c2103989b3..e7e33edef8f7acd4b1b41e9861e7a78e36158c03 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -787,11 +787,7 @@ namespace {
     }
     else
     {
-        // In case of null move search use previous static eval with a different sign
-        if ((ss-1)->currentMove != MOVE_NULL)
-            ss->staticEval = eval = evaluate(pos);
-        else
-            ss->staticEval = eval = -(ss-1)->staticEval;
+        ss->staticEval = eval = evaluate(pos);
 
         // Save static evaluation into transposition table
         if(!excludedMove)