};
-/// The UndoInfo struct stores information we need to restore a Position
+/// The StateInfo struct stores information we need to restore a Position
/// object to its previous state when we retract a move. Whenever a move
-/// is made on the board (by calling Position::do_move), an UndoInfo object
-/// must be passed as a parameter. When the move is unmade (by calling
-/// Position::undo_move), the same UndoInfo object must be passed again.
+/// is made on the board (by calling Position::do_move), an StateInfo object
+/// must be passed as a parameter.
-struct UndoInfo {
+struct StateInfo {
Bitboard pinners[2], pinned[2], dcCandidates[2], checkersBB;
Key key, pawnKey, materialKey;
int castleRights, rule50;
Move lastMove;
Value mgValue, egValue;
PieceType capture;
+ StateInfo* previous;
};
bool square_is_weak(Square s, Color c) const;
// Doing and undoing moves
- void do_move(Move m, UndoInfo &u);
- void undo_move(Move m, const UndoInfo &u);
- void do_null_move(UndoInfo &u);
- void undo_null_move(const UndoInfo &u);
+ void do_move(Move m, StateInfo& st);
+ void undo_move(Move m);
+ void do_null_move(StateInfo& st);
+ void undo_null_move();
// Static exchange evaluation
int see(Square from, Square to) const;
// Helper functions for doing and undoing moves
void do_capture_move(Move m, PieceType capture, Color them, Square to);
void do_castle_move(Move m);
- void do_promotion_move(Move m, UndoInfo &u);
+ void do_promotion_move(Move m);
void do_ep_move(Move m);
void undo_castle_move(Move m);
- void undo_promotion_move(Move m, const UndoInfo &u);
+ void undo_promotion_move(Move m);
void undo_ep_move(Move m);
void find_checkers();
+ void find_pinned();
template<PieceType Piece>
void update_checkers(Bitboard* pCheckersBB, Square ksq, Square from, Square to, Bitboard dcCandidates);
Key history[MaxGameLength];
Value npMaterial[2];
File initialKFile, initialKRFile, initialQRFile;
-
- // Info backed up in do_move()
- union {
- UndoInfo undoInfoUnion;
- struct { // Must have the same layout of UndoInfo
- mutable Bitboard pinners[2], pinned[2], dcCandidates[2];
- Bitboard checkersBB;
- Key key, pawnKey, materialKey;
- int castleRights, rule50;
- Square epSquare;
- Move lastMove;
- Value mgValue, egValue;
- PieceType capture;
- };
- };
+ StateInfo startState;
+ StateInfo* st;
// Static variables
static int castleRightsMask[64];
}
inline Square Position::ep_square() const {
- return epSquare;
+ return st->epSquare;
}
inline Square Position::king_square(Color c) const {
}
inline bool Position::can_castle_kingside(Color side) const {
- return castleRights & (1+int(side));
+ return st->castleRights & (1+int(side));
}
inline bool Position::can_castle_queenside(Color side) const {
- return castleRights & (4+4*int(side));
+ return st->castleRights & (4+4*int(side));
}
inline bool Position::can_castle(Color side) const {
return StepAttackBB[KING][s];
}
+inline Bitboard Position::pinned_pieces(Color c) const {
+ return st->pinned[c];
+}
+
+inline Bitboard Position::pinned_pieces(Color c, Bitboard& p) const {
+ p = st->pinners[c];
+ return st->pinned[c];
+}
+
+inline Bitboard Position::discovered_check_candidates(Color c) const {
+ return st->dcCandidates[c];
+}
+
inline Bitboard Position::checkers() const {
- return checkersBB;
+ return st->checkersBB;
}
inline bool Position::is_check() const {
- return checkersBB != EmptyBoardBB;
+ return st->checkersBB != EmptyBoardBB;
}
inline bool Position::pawn_attacks_square(Color c, Square f, Square t) const {
}
inline Key Position::get_key() const {
- return key;
+ return st->key;
}
inline Key Position::get_pawn_key() const {
- return pawnKey;
+ return st->pawnKey;
}
inline Key Position::get_material_key() const {
- return materialKey;
+ return st->materialKey;
}
template<Position::GamePhase Phase>
}
inline Value Position::mg_value() const {
- return mgValue;
+ return st->mgValue;
}
inline Value Position::eg_value() const {
- return egValue;
+ return st->egValue;
}
inline Value Position::non_pawn_material(Color c) const {
inline int Position::rule_50_counter() const {
- return rule50;
+ return st->rule50;
}
inline bool Position::opposite_colored_bishops() const {