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 // Note that operator< is set up such that sorting will be in descending order
68 inline bool operator<(const MoveStack& f, const MoveStack& s) { return s.score < f.score; }
70 // An helper insertion sort implementation
72 inline void insertion_sort(T* firstMove, T* lastMove)
77 if (firstMove != lastMove)
78 for (cur = firstMove + 1; cur != lastMove; cur++)
85 while (--d != firstMove && value < *--p);
91 // Our dedicated sort in range [firstMove, lastMove), first splits
92 // positive scores from ramining then order seaprately the two sets.
94 inline void sort_moves(T* firstMove, T* lastMove, T** lastPositive)
102 d->score = -1; // right guard
104 // Split positives vs non-positives
106 while ((++p)->score > 0) {}
110 while (--d != p && d->score <= 0) {}
119 // Sort just positive scored moves, remaining only when we get there
120 insertion_sort<T>(firstMove, p);
124 // Picks up the best move in range [curMove, lastMove), one per cycle.
125 // It is faster then sorting all the moves in advance when moves are few,
126 // as normally are the possible captures. Note that is not a stable alghoritm.
128 inline T pick_best(T* curMove, T* lastMove)
133 while (++curMove != lastMove)
135 if (*curMove < bestMove)
146 //// Inline functions
149 inline Square move_from(Move m) {
150 return Square((int(m) >> 6) & 0x3F);
153 inline Square move_to(Move m) {
154 return Square(m & 0x3F);
157 inline PieceType move_promotion_piece(Move m) {
158 return PieceType((int(m) >> 12) & 7);
161 inline int move_is_special(Move m) {
162 return m & (0x1F << 12);
165 inline int move_is_promotion(Move m) {
166 return m & (7 << 12);
169 inline int move_is_ep(Move m) {
170 return m & (1 << 15);
173 inline int move_is_castle(Move m) {
174 return m & (1 << 16);
177 inline bool move_is_short_castle(Move m) {
178 return move_is_castle(m) && (move_to(m) > move_from(m));
181 inline bool move_is_long_castle(Move m) {
182 return move_is_castle(m) && (move_to(m) < move_from(m));
185 inline Move make_promotion_move(Square from, Square to, PieceType promotion) {
186 return Move(int(to) | (int(from) << 6) | (int(promotion) << 12));
189 inline Move make_move(Square from, Square to) {
190 return Move(int(to) | (int(from) << 6));
193 inline Move make_castle_move(Square from, Square to) {
194 return Move(int(to) | (int(from) << 6) | (1 << 16));
197 inline Move make_ep_move(Square from, Square to) {
198 return Move(int(to) | (int(from) << 6) | (1 << 15));
206 extern std::ostream& operator<<(std::ostream& os, Move m);
207 extern Move move_from_string(const Position& pos, const std::string &str);
208 extern const std::string move_to_string(Move m, bool chess960);
209 extern bool move_is_ok(Move m);
212 #endif // !defined(MOVE_H_INCLUDED)