Count passed pawns in asymmetry measure

[stockfish] / src / pawns.cpp

diff --git a/src/pawns.cpp b/src/pawns.cpp
index 721df3729af56c4e8dc7f87a70a438ca74b90a47..5c33577445dc22e6e1e8a69c4ae9a081e6b77f22 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -88,8 +88,8 @@ namespace {
   template<Color Us>
   Score evaluate(const Position& pos, Pawns::Entry* e) {
 
-    const Color     Them  = (Us == WHITE ? BLACK      : WHITE);
-    const Direction Up    = (Us == WHITE ? NORTH      : SOUTH);
+    const Color     Them = (Us == WHITE ? BLACK : WHITE);
+    const Direction Up   = (Us == WHITE ? NORTH : SOUTH);
 
     Bitboard b, neighbours, stoppers, doubled, supported, phalanx;
     Bitboard lever, leverPush;
@@ -104,7 +104,7 @@ namespace {
     e->passedPawns[Us] = e->pawnAttacksSpan[Us] = e->weakUnopposed[Us] = 0;
     e->semiopenFiles[Us] = 0xFF;
     e->kingSquares[Us]   = SQ_NONE;
-    e->pawnAttacks[Us]   = pos.pawn_attacks<Us>(ourPawns);
+    e->pawnAttacks[Us]   = pawn_attacks_bb<Us>(ourPawns);
     e->pawnsOnSquares[Us][BLACK] = popcount(ourPawns & DarkSquares);
     e->pawnsOnSquares[Us][WHITE] = pos.count<PAWN>(Us) - e->pawnsOnSquares[Us][BLACK];
 
@@ -164,6 +164,9 @@ namespace {
                     e->passedPawns[Us] |= s;
         }
 
+        if (e->passedPawns[Us] & s)
+            e->asymmetry++;
+
         // Score this pawn
         if (supported | phalanx)
             score += Connected[opposed][bool(phalanx)][popcount(supported)][relative_rank(Us, s)];
@@ -220,10 +223,11 @@ Entry* probe(const Position& pos) {
       return e;
 
   e->key = key;
+  e->asymmetry = 0;
   e->scores[WHITE] = evaluate<WHITE>(pos, e);
   e->scores[BLACK] = evaluate<BLACK>(pos, e);
-  e->asymmetry = popcount(e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK]);
-  e->openFiles = popcount(e->semiopenFiles[WHITE] & e->semiopenFiles[BLACK]);
+  e->asymmetry += popcount(e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK]);
+  e->openFiles  = popcount(e->semiopenFiles[WHITE] & e->semiopenFiles[BLACK]);
 
   return e;
 }