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);
// 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);
&& 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];
score += Connected[opposed][!!phalanx][more_than_one(supported)][relative_rank(Us, s)];
if (doubled && !supported)
- score -= Doubled;
+ score -= Doubled;
if (lever)
score += Lever[relative_rank(Us, s)];