Bonus for pawn scrifice which create passed pawn

[stockfish] / src / pawns.cpp

diff --git a/src/pawns.cpp b/src/pawns.cpp
index 0e57f01fffc089c2b00dc60b776800467f7c93f0..95d5fb4cfeb5af4da52552430224b3622470d3cc 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -104,7 +104,6 @@ namespace {
     bool opposed, backward;
     Score score = SCORE_ZERO;
     const Square* pl = pos.squares<PAWN>(Us);
-    const Bitboard* pawnAttacksBB = StepAttacksBB[make_piece(Us, PAWN)];
 
     Bitboard ourPawns   = pos.pieces(Us  , PAWN);
     Bitboard theirPawns = pos.pieces(Them, PAWN);
@@ -129,8 +128,8 @@ namespace {
         // Flag the pawn
         opposed    = theirPawns & forward_bb(Us, s);
         stoppers   = theirPawns & passed_pawn_mask(Us, s);
-        lever      = theirPawns & pawnAttacksBB[s];
-        leverPush  = theirPawns & pawnAttacksBB[s + Up];
+        lever      = theirPawns & PawnAttacks[Us][s];
+        leverPush  = theirPawns & PawnAttacks[Us][s + Up];
         doubled    = ourPawns   & (s - Up);
         neighbours = ourPawns   & adjacent_files_bb(f);
         phalanx    = neighbours & rank_bb(s);
@@ -164,6 +163,13 @@ namespace {
             && popcount(phalanx)   >= popcount(leverPush))
             e->passedPawns[Us] |= s;
 
+        else if (    stoppers == SquareBB[s + Up]
+                 &&  relative_rank(Us, s) >= RANK_5
+                 && (b = (shift<Up>(supported) & ~theirPawns)))
+            while(b)
+                if(!more_than_one(theirPawns & PawnAttacks[Us][pop_lsb(&b)]))
+                    e->passedPawns[Us] |= s;
+
         // Score this pawn
         if (!neighbours)
             score -= Isolated[opposed];