Increase pawns cache (#2187)

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 30c22a8e65b340103fda85698f31d91e55dfcc97..3ff1460b562742a12c3f79883839d3b7db69e914 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -152,7 +152,6 @@ namespace {
   constexpr Score ThreatBySafePawn   = S(173, 94);
   constexpr Score TrappedRook        = S( 47,  4);
   constexpr Score WeakQueen          = S( 49, 15);
-  constexpr Score WeakUnopposedPawn  = S( 12, 23);
 
 #undef S
 
@@ -191,10 +190,8 @@ namespace {
     // color, including x-rays. But diagonal x-rays through pawns are not computed.
     Bitboard attackedBy2[COLOR_NB];
 
-    // kingRing[color] are the squares adjacent to the king, plus (only for a
-    // king on its first rank) the squares two ranks in front. For instance,
-    // if black's king is on g8, kingRing[BLACK] is f8, h8, f7, g7, h7, f6, g6
-    // and h6.
+    // kingRing[color] are the squares adjacent to the king plus some other
+    // very near squares, depending on king position.
     Bitboard kingRing[COLOR_NB];
 
     // kingAttackersCount[color] is the number of pieces of the given color
@@ -555,10 +552,6 @@ namespace {
 
     score += RestrictedPiece * popcount(b);
 
-    // Bonus for enemy unopposed weak pawns
-    if (pos.pieces(Us, ROOK, QUEEN))
-        score += WeakUnopposedPawn * pe->weak_unopposed(Them);
-
     // Find squares where our pawns can push on the next move
     b  = shift<Up>(pos.pieces(Us, PAWN)) & ~pos.pieces();
     b |= shift<Up>(b & TRank3BB) & ~pos.pieces();
@@ -807,7 +800,7 @@ namespace {
 
     // Early exit if score is high
     Value v = (mg_value(score) + eg_value(score)) / 2;
-    if (abs(v) > (LazyThreshold + pos.non_pawn_material() / 64))
+    if (abs(v) > LazyThreshold + pos.non_pawn_material() / 64)
        return pos.side_to_move() == WHITE ? v : -v;
 
     // Main evaluation begins here