2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
6 Stockfish is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 Stockfish is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #if !defined(MOVE_H_INCLUDED)
22 #define MOVE_H_INCLUDED
34 // Maximum number of allowed moves per position
35 const int MOVES_MAX = 256;
43 /// A move needs 17 bits to be stored
45 /// bit 0- 5: destination square (from 0 to 63)
46 /// bit 6-11: origin square (from 0 to 63)
47 /// bit 12-14: promotion piece type
48 /// bit 15: en passant flag
49 /// bit 16: castle flag
51 /// Special cases are MOVE_NONE and MOVE_NULL. We can sneak these in
52 /// because in any normal move destination square is always different
53 /// from origin square while MOVE_NONE and MOVE_NULL have the same
54 /// origin and destination square, 0 and 1 respectively.
67 inline bool operator<(const MoveStack& f, const MoveStack& s) { return f.score < s.score; }
69 // An helper insertion sort implementation, works with pointers and iterators
70 template<typename T, typename K>
71 inline void insertion_sort(K firstMove, K lastMove)
76 if (firstMove != lastMove)
77 for (cur = firstMove + 1; cur != lastMove; cur++)
84 while (--d != firstMove && *--p < value);
90 // Our dedicated sort in range [firstMove, lastMove), first splits
91 // positive scores from ramining then order seaprately the two sets.
93 inline void sort_moves(T* firstMove, T* lastMove, T** lastPositive)
101 d->score = -1; // right guard
103 // Split positives vs non-positives
105 while ((++p)->score > 0) {}
109 while (--d != p && d->score <= 0) {}
118 // Sort just positive scored moves, remaining only when we get there
119 insertion_sort<T, T*>(firstMove, p);
123 // Picks up the best move in range [curMove, lastMove), one per cycle.
124 // It is faster then sorting all the moves in advance when moves are few,
125 // as normally are the possible captures. Note that is not a stable alghoritm.
127 inline T pick_best(T* curMove, T* lastMove)
132 while (++curMove != lastMove)
134 if (bestMove < *curMove)
145 //// Inline functions
148 inline Square move_from(Move m) {
149 return Square((int(m) >> 6) & 0x3F);
152 inline Square move_to(Move m) {
153 return Square(m & 0x3F);
156 inline PieceType move_promotion_piece(Move m) {
157 return PieceType((int(m) >> 12) & 7);
160 inline int move_is_special(Move m) {
161 return m & (0x1F << 12);
164 inline int move_is_promotion(Move m) {
165 return m & (7 << 12);
168 inline int move_is_ep(Move m) {
169 return m & (1 << 15);
172 inline int move_is_castle(Move m) {
173 return m & (1 << 16);
176 inline bool move_is_short_castle(Move m) {
177 return move_is_castle(m) && (move_to(m) > move_from(m));
180 inline bool move_is_long_castle(Move m) {
181 return move_is_castle(m) && (move_to(m) < move_from(m));
184 inline Move make_promotion_move(Square from, Square to, PieceType promotion) {
185 return Move(int(to) | (int(from) << 6) | (int(promotion) << 12));
188 inline Move make_move(Square from, Square to) {
189 return Move(int(to) | (int(from) << 6));
192 inline Move make_castle_move(Square from, Square to) {
193 return Move(int(to) | (int(from) << 6) | (1 << 16));
196 inline Move make_ep_move(Square from, Square to) {
197 return Move(int(to) | (int(from) << 6) | (1 << 15));
205 extern std::ostream& operator<<(std::ostream& os, Move m);
206 extern Move move_from_uci(const Position& pos, const std::string &str);
207 extern const std::string move_to_uci(Move m, bool chess960);
208 extern bool move_is_ok(Move m);
211 #endif // !defined(MOVE_H_INCLUDED)