class Position;
+/// A move needs 17 bits to be stored
+///
+/// bit 0- 5: destination square (from 0 to 63)
+/// bit 6-11: origin square (from 0 to 63)
+/// bit 12-14: promotion piece type
+/// bit 15: en passant flag
+/// bit 16: castle flag
+///
+/// Special cases are MOVE_NONE and MOVE_NULL. We can sneak these in
+/// because in any normal move destination square is always different
+/// from origin square while MOVE_NONE and MOVE_NULL have the same
+/// origin and destination square, 0 and 1 respectively.
+
enum Move {
MOVE_NONE = 0,
- MOVE_NULL = 65,
- MOVE_MAX = 0xFFFFFF
+ MOVE_NULL = 65
};
int score;
};
+// Note that operator< is set up such that std::sort() will sort in descending order
+inline bool operator<(const MoveStack& f, const MoveStack& s) { return s.score < f.score; }
+
////
//// Inline functions
////
inline Square move_from(Move m) {
- return Square((int(m) >> 6) & 077);
+ return Square((int(m) >> 6) & 0x3F);
}
inline Square move_to(Move m) {
- return Square(m & 077);
+ return Square(m & 0x3F);
}
inline PieceType move_promotion(Move m) {