QUEEN_SIDE
};
- // Function
+ const bool CAPTURE = true;
+ const bool NON_CAPTURE = false;
+
+ // Functions
bool castling_is_check(const Position&, CastlingSide);
- // Template
+ // Helper templates
template<CastlingSide Side>
- MoveStack* generate_castle_moves(const Position&, MoveStack*);
+ MoveStack* generate_castle_moves(const Position& pos, MoveStack* mlist);
- // Template generate_pawn_captures() with specializations
- template<Color, Color, Bitboard, SquareDelta, SquareDelta, SquareDelta>
- MoveStack* do_generate_pawn_captures(const Position& pos, MoveStack* mlist);
+ template<Color Us, Rank, Bitboard, SquareDelta>
+ MoveStack* generate_pawn_blocking_evasions(const Position&, Bitboard, Bitboard, MoveStack*);
- template<Color>
- inline MoveStack* generate_pawn_captures(const Position& p, MoveStack* m) {
- return do_generate_pawn_captures<WHITE, BLACK, Rank8BB, DELTA_NE, DELTA_NW, DELTA_N>(p, m);
- }
- template<>
- inline MoveStack* generate_pawn_captures<BLACK>(const Position& p, MoveStack* m) {
- return do_generate_pawn_captures<BLACK, WHITE, Rank1BB, DELTA_SE, DELTA_SW, DELTA_S>(p, m);
- }
+ template<Color, Color, Bitboard, SquareDelta, SquareDelta, SquareDelta>
+ MoveStack* generate_pawn_captures(const Position& pos, MoveStack* mlist);
- // Template generate_pawn_noncaptures() with specializations
template<Color, Color, Bitboard, Bitboard, SquareDelta, SquareDelta, SquareDelta>
- MoveStack* do_generate_pawn_noncaptures(const Position& pos, MoveStack* mlist);
+ MoveStack* generate_pawn_noncaptures(const Position& pos, MoveStack* mlist);
- template<Color>
- inline MoveStack* generate_pawn_noncaptures(const Position& p, MoveStack* m) {
- return do_generate_pawn_noncaptures<WHITE, BLACK, Rank8BB, Rank3BB, DELTA_NE, DELTA_NW, DELTA_N>(p, m);
- }
- template<>
- inline MoveStack* generate_pawn_noncaptures<BLACK>(const Position& p, MoveStack* m) {
- return do_generate_pawn_noncaptures<BLACK, WHITE, Rank1BB, Rank6BB, DELTA_SE, DELTA_SW, DELTA_S>(p, m);
- }
+ template<Color, Color, Bitboard, Bitboard, SquareDelta>
+ MoveStack* generate_pawn_checks(const Position&, Bitboard, Square, MoveStack*);
+
+ // Template generate_piece_checks() with specializations
+ template<PieceType>
+ MoveStack* generate_piece_checks(const Position&, MoveStack*, Color, Bitboard, Square);
- // Template generate_pawn_blocking_evasions() with specializations
- template<Color Us, Rank, Bitboard, SquareDelta>
- MoveStack* do_generate_pawn_blocking_evasions(const Position& pos, Bitboard not_pinned,
- Bitboard blockSquares, MoveStack* mlist);
- template<Color>
- inline MoveStack* generate_pawn_blocking_evasions(const Position& p, Bitboard np, Bitboard bs, MoveStack* m) {
- return do_generate_pawn_blocking_evasions<WHITE, RANK_8, Rank3BB, DELTA_N>(p, np, bs, m);
- }
template<>
- inline MoveStack* generate_pawn_blocking_evasions<BLACK>(const Position& p, Bitboard np, Bitboard bs, MoveStack* m) {
- return do_generate_pawn_blocking_evasions<BLACK, RANK_1, Rank6BB, DELTA_S>(p, np, bs, m);
- }
+ inline MoveStack* generate_piece_checks<PAWN>(const Position& p, MoveStack* m, Color us, Bitboard dc, Square ksq) {
- // Template generate_pawn_checks() with specializations
- template<Color, Color, Bitboard, Bitboard, SquareDelta>
- MoveStack* do_generate_pawn_checks(const Position&, Bitboard, Square, MoveStack*);
+ if (us == WHITE)
+ return generate_pawn_checks<WHITE, BLACK, Rank8BB, Rank3BB, DELTA_N>(p, dc, ksq, m);
+ else
+ return generate_pawn_checks<BLACK, WHITE, Rank1BB, Rank6BB, DELTA_S>(p, dc, ksq, m);
- template<Color>
- inline MoveStack* generate_pawn_checks(const Position& p, Bitboard dc, Square ksq, MoveStack* m) {
- return do_generate_pawn_checks<WHITE, BLACK, Rank8BB, Rank3BB, DELTA_N>(p, dc, ksq, m);
- }
- template<>
- inline MoveStack* generate_pawn_checks<BLACK>(const Position& p, Bitboard dc, Square ksq, MoveStack* m) {
- return do_generate_pawn_checks<BLACK, WHITE, Rank1BB, Rank6BB, DELTA_S>(p, dc, ksq, m);
}
- // non-pawn templates
+ // Template generate_piece_moves() with specializations
template<PieceType>
MoveStack* generate_piece_moves(const Position&, MoveStack*, Color us, Bitboard);
+
template<>
MoveStack* generate_piece_moves<KING>(const Position& pos, MoveStack* mlist, Color us, Bitboard target);
- template<PieceType>
- MoveStack* generate_piece_checks(const Position&, Bitboard, Bitboard, Square, MoveStack*);
- MoveStack* generate_piece_checks_king(const Position&, Square, Bitboard, Square, MoveStack*);
+ template<PieceType Piece, bool Capture>
+ inline MoveStack* generate_piece_moves(const Position& p, MoveStack* m, Color us) {
+ assert(Piece == PAWN);
+
+ if (Capture)
+ return (us == WHITE ? generate_pawn_captures<WHITE, BLACK, Rank8BB, DELTA_NE, DELTA_NW, DELTA_N>(p, m)
+ : generate_pawn_captures<BLACK, WHITE, Rank1BB, DELTA_SE, DELTA_SW, DELTA_S>(p, m));
+ else
+ return (us == WHITE ? generate_pawn_noncaptures<WHITE, BLACK, Rank8BB, Rank3BB, DELTA_NE, DELTA_NW, DELTA_N>(p, m)
+ : generate_pawn_noncaptures<BLACK, WHITE, Rank1BB, Rank6BB, DELTA_SE, DELTA_SW, DELTA_S>(p, m));
+ }
+
+ // Template generate_piece_blocking_evasions() with specializations
template<PieceType>
- MoveStack* generate_piece_blocking_evasions(const Position&, Bitboard, Bitboard, MoveStack*);
+ MoveStack* generate_piece_blocking_evasions(const Position&, MoveStack*, Color us, Bitboard, Bitboard);
+
+ template<>
+ inline MoveStack* generate_piece_blocking_evasions<PAWN>(const Position& p, MoveStack* m, Color us,
+ Bitboard np, Bitboard bs) {
+ if (us == WHITE)
+ return generate_pawn_blocking_evasions<WHITE, RANK_8, Rank3BB, DELTA_N>(p, np, bs, m);
+ else
+ return generate_pawn_blocking_evasions<BLACK, RANK_1, Rank6BB, DELTA_S>(p, np, bs, m);
+ }
}
mlist = generate_piece_moves<ROOK>(pos, mlist, us, target);
mlist = generate_piece_moves<BISHOP>(pos, mlist, us, target);
mlist = generate_piece_moves<KNIGHT>(pos, mlist, us, target);
-
- if (us == WHITE)
- mlist = generate_pawn_captures<WHITE>(pos, mlist);
- else
- mlist = generate_pawn_captures<BLACK>(pos, mlist);
-
+ mlist = generate_piece_moves<PAWN, CAPTURE>(pos, mlist, us);
mlist = generate_piece_moves<KING>(pos, mlist, us, target);
return int(mlist - mlist_start);
}
/// generate_noncaptures() generates all pseudo-legal non-captures and
-/// underpromotions. The return value is the number of moves generated.
+/// underpromotions. The return value is the number of moves generated.
int generate_noncaptures(const Position& pos, MoveStack* mlist) {
Bitboard target = pos.empty_squares();
MoveStack* mlist_start = mlist;
- if (us == WHITE)
- mlist = generate_pawn_noncaptures<WHITE>(pos, mlist);
- else
- mlist = generate_pawn_noncaptures<BLACK>(pos, mlist);
-
+ mlist = generate_piece_moves<PAWN, NON_CAPTURE>(pos, mlist, us);
mlist = generate_piece_moves<KNIGHT>(pos, mlist, us, target);
mlist = generate_piece_moves<BISHOP>(pos, mlist, us, target);
mlist = generate_piece_moves<ROOK>(pos, mlist, us, target);
assert(pos.piece_on(ksq) == king_of_color(opposite_color(us)));
- dc = pos.discovered_check_candidates(us);
-
- // Pawn moves
- if (us == WHITE)
- mlist = generate_pawn_checks<WHITE>(pos, dc, ksq, mlist);
- else
- mlist = generate_pawn_checks<BLACK>(pos, dc, ksq, mlist);
-
// Pieces moves
- Bitboard b = pos.knights(us);
- if (b)
- mlist = generate_piece_checks<KNIGHT>(pos, b, dc, ksq, mlist);
-
- b = pos.bishops(us);
- if (b)
- mlist = generate_piece_checks<BISHOP>(pos, b, dc, ksq, mlist);
-
- b = pos.rooks(us);
- if (b)
- mlist = generate_piece_checks<ROOK>(pos, b, dc, ksq, mlist);
-
- b = pos.queens(us);
- if (b)
- mlist = generate_piece_checks<QUEEN>(pos, b, dc, ksq, mlist);
-
- // Hopefully we always have a king ;-)
- mlist = generate_piece_checks_king(pos, pos.king_square(us), dc, ksq, mlist);
+ mlist = generate_piece_checks<PAWN>(pos, mlist, us, dc, ksq);
+ mlist = generate_piece_checks<KNIGHT>(pos, mlist, us, dc, ksq);
+ mlist = generate_piece_checks<BISHOP>(pos, mlist, us, dc, ksq);
+ mlist = generate_piece_checks<ROOK>(pos, mlist, us, dc, ksq);
+ mlist = generate_piece_checks<QUEEN>(pos, mlist, us, dc, ksq);
+ mlist = generate_piece_checks<KING>(pos, mlist, us, dc, ksq);
// Castling moves that give check. Very rare but nice to have!
if ( pos.can_castle_queenside(us)
assert(pos.piece_on(ksq) == king_of_color(us));
- // Generate evasions for king
- Bitboard b1 = pos.piece_attacks<KING>(ksq) & ~pos.pieces_of_color(us);
+ // The bitboard of occupied pieces without our king
Bitboard b2 = pos.occupied_squares();
clear_bit(&b2, ksq);
+ // Find squares attacked by slider checkers, we will
+ // remove them from king evasions set so to avoid a couple
+ // of cycles in the slow king evasions legality check loop.
+ Bitboard checkers = pos.checkers();
+ Bitboard checkersAttacks = EmptyBoardBB;
+ Bitboard b = checkers & (pos.queens() | pos.bishops());
+ while (b)
+ {
+ from = pop_1st_bit(&b);
+ checkersAttacks |= bishop_attacks_bb(from, b2);
+ }
+
+ b = checkers & (pos.queens() | pos.rooks());
+ while (b)
+ {
+ from = pop_1st_bit(&b);
+ checkersAttacks |= rook_attacks_bb(from, b2);
+ }
+
+ // Generate evasions for king
+ Bitboard b1 = pos.piece_attacks<KING>(ksq) & ~pos.pieces_of_color(us) & ~checkersAttacks;
while (b1)
{
- to = pop_1st_bit(&b1);
-
- // Make sure 'to' is not attacked by the other side. This is a bit ugly,
- // because we can't use Position::square_is_attacked. Instead we use
- // the low-level bishop_attacks_bb and rook_attacks_bb with the bitboard
- // b2 (the occupied squares with the king removed) in order to test whether
- // the king will remain in check on the destination square.
- if (!( (pos.piece_attacks<KNIGHT>(to) & pos.knights(them))
- || (pos.pawn_attacks(us, to) & pos.pawns(them))
- || (bishop_attacks_bb(to, b2) & pos.bishops_and_queens(them))
- || (rook_attacks_bb(to, b2) & pos.rooks_and_queens(them))
- || (pos.piece_attacks<KING>(to) & pos.kings(them))))
-
- (*mlist++).move = make_move(ksq, to);
+ to = pop_1st_bit(&b1);
+
+ // Make sure 'to' is not attacked by the other side. This is a bit ugly,
+ // because we can't use Position::square_is_attacked. Instead we use
+ // the low-level bishop_attacks_bb and rook_attacks_bb with the bitboard
+ // b2 (the occupied squares with the king removed) in order to test whether
+ // the king will remain in check on the destination square.
+ if (!( (pos.piece_attacks<KNIGHT>(to) & pos.knights(them))
+ || (pos.pawn_attacks(us, to) & pos.pawns(them))
+ || (bishop_attacks_bb(to, b2) & pos.bishops_and_queens(them))
+ || (rook_attacks_bb(to, b2) & pos.rooks_and_queens(them))
+ || (pos.piece_attacks<KING>(to) & pos.kings(them))))
+ (*mlist++).move = make_move(ksq, to);
}
// Generate evasions for other pieces only if not double check. We use a
// simple bit twiddling hack here rather than calling count_1s in order to
// save some time (we know that pos.checkers() has at most two nonzero bits).
- Bitboard checkers = pos.checkers();
-
if (!(checkers & (checkers - 1))) // Only one bit set?
{
Square checksq = first_1(checkers);
assert((pos.occupied_squares() & blockSquares) == EmptyBoardBB);
- // Pawn moves. Because a blocking evasion can never be a capture, we
- // only generate pawn pushes.
- if (us == WHITE)
- mlist = generate_pawn_blocking_evasions<WHITE>(pos, not_pinned, blockSquares, mlist);
- else
- mlist = generate_pawn_blocking_evasions<BLACK>(pos, not_pinned, blockSquares, mlist);
-
// Pieces moves
- b1 = pos.knights(us) & not_pinned;
- if (b1)
- mlist = generate_piece_blocking_evasions<KNIGHT>(pos, b1, blockSquares, mlist);
-
- b1 = pos.bishops(us) & not_pinned;
- if (b1)
- mlist = generate_piece_blocking_evasions<BISHOP>(pos, b1, blockSquares, mlist);
-
- b1 = pos.rooks(us) & not_pinned;
- if (b1)
- mlist = generate_piece_blocking_evasions<ROOK>(pos, b1, blockSquares, mlist);
-
- b1 = pos.queens(us) & not_pinned;
- if (b1)
- mlist = generate_piece_blocking_evasions<QUEEN>(pos, b1, blockSquares, mlist);
+ mlist = generate_piece_blocking_evasions<PAWN>(pos, mlist, us, not_pinned, blockSquares);
+ mlist = generate_piece_blocking_evasions<KNIGHT>(pos, mlist, us, not_pinned, blockSquares);
+ mlist = generate_piece_blocking_evasions<BISHOP>(pos, mlist, us, not_pinned, blockSquares);
+ mlist = generate_piece_blocking_evasions<ROOK>(pos, mlist, us, not_pinned, blockSquares);
+ mlist = generate_piece_blocking_evasions<QUEEN>(pos, mlist, us, not_pinned, blockSquares);
}
// Finally, the ugly special case of en passant captures. An en passant
}
template<PieceType Piece>
- MoveStack* generate_piece_blocking_evasions(const Position& pos, Bitboard b,
- Bitboard blockSquares, MoveStack* mlist) {
+ MoveStack* generate_piece_blocking_evasions(const Position& pos, MoveStack* mlist, Color us,
+ Bitboard not_pinned, Bitboard blockSquares) {
+
+ Bitboard b = pos.pieces_of_color_and_type(us, Piece) & not_pinned;
while (b)
{
Square from = pop_1st_bit(&b);
return mlist;
}
-
template<Color Us, Color Them, Bitboard TRank8BB, SquareDelta TDELTA_NE,
SquareDelta TDELTA_NW, SquareDelta TDELTA_N
>
- MoveStack* do_generate_pawn_captures(const Position& pos, MoveStack* mlist) {
+ MoveStack* generate_pawn_captures(const Position& pos, MoveStack* mlist) {
Square to;
Bitboard pawns = pos.pawns(Us);
template<Color Us, Color Them, Bitboard TRank8BB, Bitboard TRank3BB,
SquareDelta TDELTA_NE, SquareDelta TDELTA_NW, SquareDelta TDELTA_N
>
- MoveStack* do_generate_pawn_noncaptures(const Position& pos, MoveStack* mlist) {
+ MoveStack* generate_pawn_noncaptures(const Position& pos, MoveStack* mlist) {
Bitboard pawns = pos.pawns(Us);
Bitboard enemyPieces = pos.pieces_of_color(Them);
template<Color Us, Color Them, Bitboard TRank8BB, Bitboard TRank3BB, SquareDelta TDELTA_N>
- MoveStack* do_generate_pawn_checks(const Position& pos, Bitboard dc, Square ksq, MoveStack* mlist)
+ MoveStack* generate_pawn_checks(const Position& pos, Bitboard dc, Square ksq, MoveStack* mlist)
{
- // Pawn moves which give discovered check. This is possible only if the
- // pawn is not on the same file as the enemy king, because we don't
- // generate captures.
- Bitboard empty = pos.empty_squares();
-
// Find all friendly pawns not on the enemy king's file
- Bitboard b1 = pos.pawns(Us) & ~file_bb(ksq), b2, b3;
+ Bitboard b1, b2, b3;
+ Bitboard empty = pos.empty_squares();
- // Discovered checks, single pawn pushes, no promotions
- b2 = b3 = (Us == WHITE ? (b1 & dc) << 8 : (b1 & dc) >> 8) & empty & ~TRank8BB;
- while (b3)
+ if (dc != EmptyBoardBB)
{
- Square to = pop_1st_bit(&b3);
- (*mlist++).move = make_move(to - TDELTA_N, to);
- }
+ // Pawn moves which gives discovered check. This is possible only if the
+ // pawn is not on the same file as the enemy king, because we don't
+ // generate captures.
+ b1 = pos.pawns(Us) & ~file_bb(ksq);
+
+ // Discovered checks, single pawn pushes, no promotions
+ b2 = b3 = (Us == WHITE ? (b1 & dc) << 8 : (b1 & dc) >> 8) & empty & ~TRank8BB;
+ while (b3)
+ {
+ Square to = pop_1st_bit(&b3);
+ (*mlist++).move = make_move(to - TDELTA_N, to);
+ }
- // Discovered checks, double pawn pushes
- b3 = (Us == WHITE ? (b2 & TRank3BB) << 8 : (b2 & TRank3BB) >> 8) & empty;
- while (b3)
- {
- Square to = pop_1st_bit(&b3);
- (*mlist++).move = make_move(to - TDELTA_N - TDELTA_N, to);
+ // Discovered checks, double pawn pushes
+ b3 = (Us == WHITE ? (b2 & TRank3BB) << 8 : (b2 & TRank3BB) >> 8) & empty;
+ while (b3)
+ {
+ Square to = pop_1st_bit(&b3);
+ (*mlist++).move = make_move(to - TDELTA_N - TDELTA_N, to);
+ }
}
// Direct checks. These are possible only for pawns on neighboring files
- // of the enemy king
- b1 &= (~dc & neighboring_files_bb(ksq));
+ // of the enemy king.
+ b1 = pos.pawns(Us) & neighboring_files_bb(ksq) & ~dc;
// Direct checks, single pawn pushes
b2 = (Us == WHITE ? b1 << 8 : b1 >> 8) & empty;
b3 = (Us == WHITE ? (b2 & TRank3BB) << 8 : (b2 & TRank3BB) >> 8)
& empty
& pos.pawn_attacks(Them, ksq);
-
while (b3)
{
Square to = pop_1st_bit(&b3);
}
template<PieceType Piece>
- MoveStack* generate_piece_checks(const Position& pos, Bitboard target, Bitboard dc,
- Square ksq, MoveStack* mlist) {
+ MoveStack* generate_piece_checks(const Position& pos, MoveStack* mlist, Color us,
+ Bitboard dc, Square ksq) {
+
+ Bitboard target = pos.pieces_of_color_and_type(us, Piece);
+
// Discovered checks
Bitboard b = target & dc;
while (b)
{
Square from = pop_1st_bit(&b);
Bitboard bb = pos.piece_attacks<Piece>(from) & pos.empty_squares();
+ if (Piece == KING)
+ bb &= ~QueenPseudoAttacks[ksq];
+
SERIALIZE_MOVES(bb);
}
+
// Direct checks
b = target & ~dc;
+ if (Piece == KING || !b)
+ return mlist;
+
Bitboard checkSqs = pos.piece_attacks<Piece>(ksq) & pos.empty_squares();
while (b)
{
return mlist;
}
- MoveStack* generate_piece_checks_king(const Position& pos, Square from, Bitboard dc,
- Square ksq, MoveStack* mlist) {
- if (bit_is_set(dc, from))
- {
- Bitboard b = pos.piece_attacks<KING>(from)
- & pos.empty_squares()
- & ~QueenPseudoAttacks[ksq];
- SERIALIZE_MOVES(b);
- }
- return mlist;
- }
-
-
template<Color Us, Rank TRANK_8, Bitboard TRank3BB, SquareDelta TDELTA_N>
- MoveStack* do_generate_pawn_blocking_evasions(const Position& pos, Bitboard not_pinned,
- Bitboard blockSquares, MoveStack* mlist) {
+ MoveStack* generate_pawn_blocking_evasions(const Position& pos, Bitboard not_pinned,
+ Bitboard blockSquares, MoveStack* mlist) {
Square to;
// Find non-pinned pawns
File rookFile = (side == QUEEN_SIDE ? FILE_D : FILE_F);
Color us = pos.side_to_move();
Square ksq = pos.king_square(us);
- Bitboard occ = pos.occupied_squares(), oppKingBB = EmptyBoardBB;
+ Bitboard occ = pos.occupied_squares();
- set_bit(&oppKingBB, pos.king_square(opposite_color(us)));
clear_bit(&occ, ksq); // Remove our king from the board
Square rsq = make_square(rookFile, square_rank(ksq));
- return (rook_attacks_bb(rsq, occ) & oppKingBB);
+ return bit_is_set(rook_attacks_bb(rsq, occ), pos.king_square(opposite_color(us)));
}
}
projects / stockfish / blobdiff