/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2009 Marco Costalba
+ Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include "piece.h"
#include "square.h"
+// Maximum number of allowed moves per position
+const int MOVES_MAX = 256;
////
//// Types
int score;
};
-// Note that operator< is set up such that sorting will be in descending order
-inline bool operator<(const MoveStack& f, const MoveStack& s) { return s.score < f.score; }
+inline bool operator<(const MoveStack& f, const MoveStack& s) { return f.score < s.score; }
-// Our stable insertion sort in range [firstMove, lastMove), platform independent
-template<typename T>
-inline void sort_moves(T* firstMove, T* lastMove)
+// An helper insertion sort implementation, works with pointers and iterators
+template<typename T, typename K>
+inline void insertion_sort(K firstMove, K lastMove)
{
T value;
- T *cur, *p, *d;
+ K cur, p, d;
if (firstMove != lastMove)
- for (cur = firstMove; ++cur != lastMove; )
+ for (cur = firstMove + 1; cur != lastMove; cur++)
{
p = d = cur;
value = *p--;
- if (value < *p)
+ if (*p < value)
{
do *d = *p;
- while (--d != firstMove && value < *--p);
+ while (--d != firstMove && *--p < value);
*d = value;
}
}
}
+// Our dedicated sort in range [firstMove, lastMove), first splits
+// positive scores from ramining then order seaprately the two sets.
+template<typename T>
+inline void sort_moves(T* firstMove, T* lastMove, T** lastPositive)
+{
+ T tmp;
+ T *p, *d;
+
+ d = lastMove;
+ p = firstMove - 1;
+
+ d->score = -1; // right guard
+
+ // Split positives vs non-positives
+ do {
+ while ((++p)->score > 0) {}
+
+ if (p != d)
+ {
+ while (--d != p && d->score <= 0) {}
+
+ tmp = *p;
+ *p = *d;
+ *d = tmp;
+ }
+
+ } while (p != d);
+
+ // Sort just positive scored moves, remaining only when we get there
+ insertion_sort<T, T*>(firstMove, p);
+ *lastPositive = p;
+}
+
// Picks up the best move in range [curMove, lastMove), one per cycle.
// It is faster then sorting all the moves in advance when moves are few,
// as normally are the possible captures. Note that is not a stable alghoritm.
bestMove = *curMove;
while (++curMove != lastMove)
{
- if (*curMove < bestMove)
+ if (bestMove < *curMove)
{
tmp = *curMove;
*curMove = bestMove;
//// Prototypes
////
-extern std::ostream& operator<<(std::ostream &os, Move m);
-extern Move move_from_string(const Position &pos, const std::string &str);
-extern const std::string move_to_string(Move m);
+extern std::ostream& operator<<(std::ostream& os, Move m);
+extern Move move_from_uci(const Position& pos, const std::string &str);
+extern const std::string move_to_uci(Move m, bool chess960);
extern bool move_is_ok(Move m);