/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008 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
//// Includes
////
+#include "bitboard.h"
#include "position.h"
-
+#include "value.h"
////
//// Types
////
+const int PawnTableSize = 16384;
+
/// PawnInfo 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
+/// 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 {
friend class PawnInfoTable;
public:
- Value mg_value() const;
- Value eg_value() const;
- Value kingside_storm_value(Color c) const;
- Value queenside_storm_value(Color c) const;
- Bitboard passed_pawns() const;
- bool file_is_half_open(Color c, File f) const;
- bool has_open_file_to_left(Color c, File f) const;
- bool has_open_file_to_right(Color c, File f) const;
+ Score pawns_value() const;
+ Bitboard pawn_attacks(Color c) const;
+ Bitboard passed_pawns(Color c) const;
+ int file_is_half_open(Color c, File f) const;
+ int has_open_file_to_left(Color c, File f) const;
+ int has_open_file_to_right(Color c, File f) const;
+
+ template<Color Us>
+ Score king_shelter(const Position& pos, Square ksq);
private:
- void clear();
+ template<Color Us>
+ Score updateShelter(const Position& pos, Square ksq);
Key key;
- Bitboard passedPawns;
- int16_t mgValue, egValue;
- int16_t ksStormValue[2], qsStormValue[2];
- uint8_t halfOpenFiles[2];
+ Bitboard passedPawns[2];
+ Bitboard pawnAttacks[2];
+ Square kingSquares[2];
+ Score value;
+ int halfOpenFiles[2];
+ Score kingShelters[2];
};
-
/// 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
class PawnInfoTable {
+ enum SideType { KingSide, QueenSide };
+
+ PawnInfoTable(const PawnInfoTable&);
+ PawnInfoTable& operator=(const PawnInfoTable&);
+
public:
- PawnInfoTable(unsigned numOfEntries);
+ PawnInfoTable();
~PawnInfoTable();
- void clear();
- PawnInfo *get_pawn_info(const Position &pos);
+ PawnInfo* get_pawn_info(const Position& pos) const;
+ void prefetch(Key key) const;
private:
- unsigned size;
- PawnInfo *entries;
+ template<Color Us>
+ Score evaluate_pawns(const Position& pos, Bitboard ourPawns, Bitboard theirPawns, PawnInfo* pi) const;
+
+ PawnInfo* entries;
};
//// Inline functions
////
-inline Value PawnInfo::mg_value() const {
- return Value(mgValue);
-}
+inline void PawnInfoTable::prefetch(Key key) const {
-inline Value PawnInfo::eg_value() const {
- return Value(egValue);
+ unsigned index = unsigned(key & (PawnTableSize - 1));
+ PawnInfo* pi = entries + index;
+ ::prefetch((char*) pi);
}
-inline Bitboard PawnInfo::passed_pawns() const {
- return passedPawns;
+inline Score PawnInfo::pawns_value() const {
+ return value;
}
-inline Value PawnInfo::kingside_storm_value(Color c) const {
- return Value(ksStormValue[c]);
+inline Bitboard PawnInfo::pawn_attacks(Color c) const {
+ return pawnAttacks[c];
}
-inline Value PawnInfo::queenside_storm_value(Color c) const {
- return Value(qsStormValue[c]);
+inline Bitboard PawnInfo::passed_pawns(Color c) const {
+ return passedPawns[c];
}
-inline bool PawnInfo::file_is_half_open(Color c, File f) const {
+inline int PawnInfo::file_is_half_open(Color c, File f) const {
return (halfOpenFiles[c] & (1 << int(f)));
}
-inline bool PawnInfo::has_open_file_to_left(Color c, File f) const {
+inline int PawnInfo::has_open_file_to_left(Color c, File f) const {
return halfOpenFiles[c] & ((1 << int(f)) - 1);
}
-inline bool PawnInfo::has_open_file_to_right(Color c, File f) const {
+inline int PawnInfo::has_open_file_to_right(Color c, File f) const {
return halfOpenFiles[c] & ~((1 << int(f+1)) - 1);
}
-inline void PawnInfo::clear() {
-
- passedPawns = EmptyBoardBB;
- mgValue = egValue = 0;
- ksStormValue[WHITE] = ksStormValue[BLACK] = 0;
- qsStormValue[WHITE] = qsStormValue[BLACK] = 0;
- halfOpenFiles[WHITE] = halfOpenFiles[BLACK] = 0xFF;
+/// 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);
+}
#endif // !defined(PAWNS_H_INCLUDED)
projects / stockfish / blobdiff