Asymmetry bonus for the attacking side

[stockfish] / src / pawns.cpp

diff --git a/src/pawns.cpp b/src/pawns.cpp
index 47f74f84ee77888d60dacf0e03251977d3cc82ff..e2fcfc79b2f799c7b9b549c5a2af9e688926afa8 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -243,6 +243,7 @@ Entry* probe(const Position& pos) {
 
   e->key = key;
   e->score = evaluate<WHITE>(pos, e) - evaluate<BLACK>(pos, e);
+  e->asymmetry = popcount<Max15>( e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK] );
   return e;
 }