Remove and replace DoubledIsolated penalty by Doubled

[stockfish] / src / pawns.cpp

diff --git a/src/pawns.cpp b/src/pawns.cpp
index a2063a8f8323cd9ad420e81d8cfe60cd93099ff6..f9dbcae2932f01a2c8a3d7381af8d183fd42f452 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -86,7 +86,7 @@ namespace {
     e->passedPawns[Us] = 0;
     e->kingSquares[Us] = SQ_NONE;
     e->pawnAttacks[Us] = e->pawnAttacksSpan[Us] = pawn_attacks_bb<Us>(ourPawns);
-    e->blockedCount[Us] = 0;
+    e->blockedCount += popcount(shift<Up>(ourPawns) & (theirPawns | doubleAttackThem));
 
     // Loop through all pawns of the current color and score each pawn
     while ((s = *pl++) != SQ_NONE)
@@ -106,8 +106,6 @@ namespace {
         phalanx    = neighbours & rank_bb(s);
         support    = neighbours & rank_bb(s - Up);
 
-        e->blockedCount[Us] += bool(blocked);
-
         // A pawn is backward when it is behind all pawns of the same color on
         // the adjacent files and cannot safely advance.
         backward =  !(neighbours & forward_ranks_bb(Them, s + Up))
@@ -145,9 +143,16 @@ namespace {
         }
 
         else if (!neighbours)
+        {
             score -=   Isolated
                      + WeakUnopposed * !opposed;
 
+            if (   (ourPawns & forward_file_bb(Them, s))
+                && popcount(opposed) == 1
+                && !(theirPawns & adjacent_files_bb(s)))
+                score -= Doubled;
+        }
+
         else if (backward)
             score -=   Backward
                      + WeakUnopposed * !opposed;
@@ -178,6 +183,7 @@ Entry* probe(const Position& pos) {
       return e;
 
   e->key = key;
+  e->blockedCount = 0;
   e->scores[WHITE] = evaluate<WHITE>(pos, e);
   e->scores[BLACK] = evaluate<BLACK>(pos, e);
 
@@ -208,7 +214,7 @@ Score Entry::evaluate_shelter(const Position& pos, Square ksq) {
       b = theirPawns & file_bb(f);
       int theirRank = b ? relative_rank(Us, frontmost_sq(Them, b)) : 0;
 
-      File d = File(edge_distance(f));
+      int d = edge_distance(f);
       bonus += make_score(ShelterStrength[d][ourRank], 0);
 
       if (ourRank && (ourRank == theirRank - 1))
@@ -244,7 +250,7 @@ Score Entry::do_king_safety(const Position& pos) {
 
   // In endgame we like to bring our king near our closest pawn
   Bitboard pawns = pos.pieces(Us, PAWN);
-  int minPawnDist = pawns ? 8 : 0;
+  int minPawnDist = 6;
 
   if (pawns & PseudoAttacks[KING][ksq])
       minPawnDist = 1;