using std::string;
+namespace Stockfish {
+
namespace Zobrist {
Key psq[PIECE_NB][SQUARE_NB];
<< std::setfill(' ') << std::dec << "\nCheckers: ";
for (Bitboard b = pos.checkers(); b; )
- os << UCI::square(pop_lsb(&b)) << " ";
+ os << UCI::square(pop_lsb(b)) << " ";
if ( int(Tablebases::MaxCardinality) >= popcount(pos.pieces())
&& !pos.can_castle(ANY_CASTLING))
{
StateInfo st;
- ASSERT_ALIGNED(&st, Eval::NNUE::kCacheLineSize);
+ ASSERT_ALIGNED(&st, Eval::NNUE::CacheLineSize);
Position p;
p.set(pos.fen(), pos.is_chess960(), &st, pos.this_thread());
chess960 = isChess960;
thisThread = th;
set_state(st);
- st->accumulator.state[WHITE] = Eval::NNUE::INIT;
- st->accumulator.state[BLACK] = Eval::NNUE::INIT;
assert(pos_is_ok());
Square kto = relative_square(c, cr & KING_SIDE ? SQ_G1 : SQ_C1);
Square rto = relative_square(c, cr & KING_SIDE ? SQ_F1 : SQ_D1);
- castlingPath[cr] = (between_bb(rfrom, rto) | between_bb(kfrom, kto) | rto | kto)
+ castlingPath[cr] = (between_bb(rfrom, rto) | between_bb(kfrom, kto))
& ~(kfrom | rfrom);
}
for (Bitboard b = pieces(); b; )
{
- Square s = pop_lsb(&b);
+ Square s = pop_lsb(b);
Piece pc = piece_on(s);
si->key ^= Zobrist::psq[pc][s];
/// Position::fen() returns a FEN representation of the position. In case of
/// Chess960 the Shredder-FEN notation is used. This is mainly a debugging function.
-const string Position::fen() const {
+string Position::fen() const {
int emptyCnt;
std::ostringstream ss;
while (snipers)
{
- Square sniperSq = pop_lsb(&snipers);
+ Square sniperSq = pop_lsb(snipers);
Bitboard b = between_bb(s, sniperSq) & occupancy;
if (b && !more_than_one(b))
if (attackers_to(s) & pieces(~us))
return false;
- // In case of Chess960, verify that when moving the castling rook we do
- // not discover some hidden checker.
+ // In case of Chess960, verify if the Rook blocks some checks
// For instance an enemy queen in SQ_A1 when castling rook is in SQ_B1.
- return !chess960
- || !(attacks_bb<ROOK>(to, pieces() ^ to_sq(m)) & pieces(~us, ROOK, QUEEN));
+ return !chess960 || !(blockers_for_king(us) & to_sq(m));
}
// If the moving piece is a king, check whether the destination square is
// attacked by the opponent.
if (type_of(piece_on(from)) == KING)
- return !(attackers_to(to) & pieces(~us));
+ return !(attackers_to(to, pieces() ^ from) & pieces(~us));
// A non-king move is legal if and only if it is not pinned or it
// is moving along the ray towards or away from the king.
- return !(blockers_for_king(us) & from)
- || aligned(from, to, square<KING>(us));
+ return !(blockers_for_king(us) & from)
+ || aligned(from, to, square<KING>(us));
}
if (more_than_one(checkers()))
return false;
- // Our move must be a blocking evasion or a capture of the checking piece
- if (!((between_bb(lsb(checkers()), square<KING>(us)) | checkers()) & to))
+ // Our move must be a blocking interposition or a capture of the checking piece
+ if (!(between_bb(square<KING>(us), lsb(checkers())) & to))
return false;
}
// In case of king moves under check we have to remove king so as to catch
return (attacks_bb< ROOK>(square<KING>(~sideToMove), b) & pieces(sideToMove, QUEEN, ROOK))
| (attacks_bb<BISHOP>(square<KING>(~sideToMove), b) & pieces(sideToMove, QUEEN, BISHOP));
}
- case CASTLING:
+ default: //CASTLING
{
- Square kfrom = from;
- Square rfrom = to; // Castling is encoded as 'king captures the rook'
- Square kto = relative_square(sideToMove, rfrom > kfrom ? SQ_G1 : SQ_C1);
- Square rto = relative_square(sideToMove, rfrom > kfrom ? SQ_F1 : SQ_D1);
+ // Castling is encoded as 'king captures the rook'
+ Square ksq = square<KING>(~sideToMove);
+ Square rto = relative_square(sideToMove, to > from ? SQ_F1 : SQ_D1);
- return (attacks_bb<ROOK>(rto) & square<KING>(~sideToMove))
- && (attacks_bb<ROOK>(rto, (pieces() ^ kfrom ^ rfrom) | rto | kto) & square<KING>(~sideToMove));
+ return (attacks_bb<ROOK>(rto) & ksq)
+ && (attacks_bb<ROOK>(rto, pieces() ^ from ^ to) & ksq);
}
- default:
- assert(false);
- return false;
}
}
++st->pliesFromNull;
// Used by NNUE
- st->accumulator.state[WHITE] = Eval::NNUE::EMPTY;
- st->accumulator.state[BLACK] = Eval::NNUE::EMPTY;
+ st->accumulator.computed[WHITE] = false;
+ st->accumulator.computed[BLACK] = false;
auto& dp = st->dirtyPiece;
dp.dirty_num = 1;
}
-/// Position::do(undo)_null_move() is used to do(undo) a "null move": it flips
+/// Position::do_null_move() is used to do a "null move": it flips
/// the side to move without executing any move on the board.
void Position::do_null_move(StateInfo& newSt) {
st->dirtyPiece.dirty_num = 0;
st->dirtyPiece.piece[0] = NO_PIECE; // Avoid checks in UpdateAccumulator()
- st->accumulator.state[WHITE] = Eval::NNUE::EMPTY;
- st->accumulator.state[BLACK] = Eval::NNUE::EMPTY;
+ st->accumulator.computed[WHITE] = false;
+ st->accumulator.computed[BLACK] = false;
if (st->epSquare != SQ_NONE)
{
}
st->key ^= Zobrist::side;
+ ++st->rule50;
prefetch(TT.first_entry(key()));
- ++st->rule50;
st->pliesFromNull = 0;
sideToMove = ~sideToMove;
assert(pos_is_ok());
}
+
+/// Position::undo_null_move() must be used to undo a "null move"
+
void Position::undo_null_move() {
assert(!checkers());
if (swap <= 0)
return true;
+ assert(color_of(piece_on(from)) == sideToMove);
Bitboard occupied = pieces() ^ from ^ to;
- Color stm = color_of(piece_on(from));
+ Color stm = sideToMove;
Bitboard attackers = attackers_to(to, occupied);
Bitboard stmAttackers, bb;
int res = 1;
if (!(stmAttackers = attackers & pieces(stm)))
break;
- // Don't allow pinned pieces to attack (except the king) as long as
- // there are pinners on their original square.
+ // Don't allow pinned pieces to attack as long as there are
+ // pinners on their original square.
if (pinners(~stm) & occupied)
stmAttackers &= ~blockers_for_king(stm);
if ((swap = PawnValueMg - swap) < res)
break;
- occupied ^= lsb(bb);
+ occupied ^= least_significant_square_bb(bb);
attackers |= attacks_bb<BISHOP>(to, occupied) & pieces(BISHOP, QUEEN);
}
if ((swap = KnightValueMg - swap) < res)
break;
- occupied ^= lsb(bb);
+ occupied ^= least_significant_square_bb(bb);
}
else if ((bb = stmAttackers & pieces(BISHOP)))
if ((swap = BishopValueMg - swap) < res)
break;
- occupied ^= lsb(bb);
+ occupied ^= least_significant_square_bb(bb);
attackers |= attacks_bb<BISHOP>(to, occupied) & pieces(BISHOP, QUEEN);
}
if ((swap = RookValueMg - swap) < res)
break;
- occupied ^= lsb(bb);
+ occupied ^= least_significant_square_bb(bb);
attackers |= attacks_bb<ROOK>(to, occupied) & pieces(ROOK, QUEEN);
}
if ((swap = QueenValueMg - swap) < res)
break;
- occupied ^= lsb(bb);
+ occupied ^= least_significant_square_bb(bb);
attackers |= (attacks_bb<BISHOP>(to, occupied) & pieces(BISHOP, QUEEN))
| (attacks_bb<ROOK >(to, occupied) & pieces(ROOK , QUEEN));
}
Square s1 = from_sq(move);
Square s2 = to_sq(move);
- if (!(between_bb(s1, s2) & pieces()))
+ if (!((between_bb(s1, s2) ^ s2) & pieces()))
{
if (ply > i)
return true;
assert(0 && "pos_is_ok: Bitboards");
StateInfo si = *st;
- ASSERT_ALIGNED(&si, Eval::NNUE::kCacheLineSize);
+ ASSERT_ALIGNED(&si, Eval::NNUE::CacheLineSize);
set_state(&si);
if (std::memcmp(&si, st, sizeof(StateInfo)))
return true;
}
+
+} // namespace Stockfish