/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2012 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
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-
#if !defined(PAWNS_H_INCLUDED)
#define PAWNS_H_INCLUDED
-////
-//// Includes
-////
-
-#include "bitboard.h"
+#include "misc.h"
#include "position.h"
-#include "value.h"
-
-////
-//// Types
-////
+#include "types.h"
const int PawnTableSize = 16384;
-/// PawnInfo is a class which contains various information about a pawn
+/// PawnEntry is a class which contains various information about a pawn
/// structure. Currently, it only includes a middle game and an end game
/// pawn structure evaluation, and a bitboard of passed pawns. We may want
-/// to add further information in the future. A lookup to the pawn hash table
-/// (performed by calling the get_pawn_info method in a PawnInfoTable object)
-/// returns a pointer to a PawnInfo object.
-class PawnInfo {
+/// to add further information in the future. A lookup to the pawn hash
+/// table (performed by calling the probe method in a PawnTable object)
+/// returns a pointer to a PawnEntry object.
+
+class PawnEntry {
- friend class PawnInfoTable;
+ friend struct PawnTable;
public:
Score pawns_value() const;
int has_open_file_to_right(Color c, File f) const;
template<Color Us>
- Score king_shelter(const Position& pos, Square ksq);
+ Score king_safety(const Position& pos, Square ksq);
private:
template<Color Us>
- Score updateShelter(const Position& pos, Square ksq);
+ Score update_safety(const Position& pos, Square ksq);
+
+ template<Color Us>
+ Value shelter_storm(const Position& pos, Square ksq);
Key key;
- Bitboard passedPawns[2];
- Bitboard pawnAttacks[2];
- Square kingSquares[2];
+ Bitboard passedPawns[COLOR_NB];
+ Bitboard pawnAttacks[COLOR_NB];
+ Square kingSquares[COLOR_NB];
+ int minKPdistance[COLOR_NB];
+ int castleRights[COLOR_NB];
Score value;
- int halfOpenFiles[2];
- Score kingShelters[2];
+ int halfOpenFiles[COLOR_NB];
+ Score kingSafety[COLOR_NB];
};
-/// The PawnInfoTable class represents a pawn hash table. It is basically
-/// just an array of PawnInfo objects and a few methods for accessing these
-/// objects. The most important method is get_pawn_info, which looks up a
-/// position in the table and returns a pointer to a PawnInfo object.
-class PawnInfoTable {
+/// The PawnTable class represents a pawn hash table. The most important
+/// method is probe, which returns a pointer to a PawnEntry object.
- enum SideType { KingSide, QueenSide };
+struct PawnTable {
- PawnInfoTable(const PawnInfoTable&);
- PawnInfoTable& operator=(const PawnInfoTable&);
-
-public:
- PawnInfoTable();
- ~PawnInfoTable();
- PawnInfo* get_pawn_info(const Position& pos) const;
- void prefetch(Key key) const;
+ PawnEntry* probe(const Position& pos);
-private:
template<Color Us>
- Score evaluate_pawns(const Position& pos, Bitboard ourPawns, Bitboard theirPawns, PawnInfo* pi) const;
+ static Score evaluate_pawns(const Position& pos, Bitboard ourPawns,
+ Bitboard theirPawns, PawnEntry* e);
- PawnInfo* entries;
+ HashTable<PawnEntry, PawnTableSize> entries;
};
-////
-//// Inline functions
-////
-
-inline void PawnInfoTable::prefetch(Key key) const {
-
- unsigned index = unsigned(key & (PawnTableSize - 1));
- PawnInfo* pi = entries + index;
- ::prefetch((char*) pi);
-}
-
-inline Score PawnInfo::pawns_value() const {
+inline Score PawnEntry::pawns_value() const {
return value;
}
-inline Bitboard PawnInfo::pawn_attacks(Color c) const {
+inline Bitboard PawnEntry::pawn_attacks(Color c) const {
return pawnAttacks[c];
}
-inline Bitboard PawnInfo::passed_pawns(Color c) const {
+inline Bitboard PawnEntry::passed_pawns(Color c) const {
return passedPawns[c];
}
-inline int PawnInfo::file_is_half_open(Color c, File f) const {
- return (halfOpenFiles[c] & (1 << int(f)));
+inline int PawnEntry::file_is_half_open(Color c, File f) const {
+ return halfOpenFiles[c] & (1 << int(f));
}
-inline int PawnInfo::has_open_file_to_left(Color c, File f) const {
+inline int PawnEntry::has_open_file_to_left(Color c, File f) const {
return halfOpenFiles[c] & ((1 << int(f)) - 1);
}
-inline int PawnInfo::has_open_file_to_right(Color c, File f) const {
+inline int PawnEntry::has_open_file_to_right(Color c, File f) const {
return halfOpenFiles[c] & ~((1 << int(f+1)) - 1);
}
-/// PawnInfo::updateShelter() calculates and caches king shelter. It is called
-/// only when king square changes, about 20% of total king_shelter() calls.
-template<Color Us>
-Score PawnInfo::updateShelter(const Position& pos, Square ksq) {
-
- const int Shift = (Us == WHITE ? 8 : -8);
-
- Bitboard pawns;
- int r, shelter = 0;
-
- if (relative_rank(Us, ksq) <= RANK_4)
- {
- pawns = pos.pieces(PAWN, Us) & this_and_neighboring_files_bb(ksq);
- r = square_rank(ksq) * 8;
- for (int i = 1; i < 4; i++)
- {
- r += Shift;
- shelter += BitCount8Bit[(pawns >> r) & 0xFF] * (128 >> i);
- }
- }
- kingSquares[Us] = ksq;
- kingShelters[Us] = make_score(shelter, 0);
- return kingShelters[Us];
-}
-
template<Color Us>
-inline Score PawnInfo::king_shelter(const Position& pos, Square ksq) {
- return kingSquares[Us] == ksq ? kingShelters[Us] : updateShelter<Us>(pos, ksq);
+inline Score PawnEntry::king_safety(const Position& pos, Square ksq) {
+ return kingSquares[Us] == ksq && castleRights[Us] == pos.can_castle(Us)
+ ? kingSafety[Us] : update_safety<Us>(pos, ksq);
}
#endif // !defined(PAWNS_H_INCLUDED)
projects / stockfish / blobdiff