/*
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) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2015-2018 Marco Costalba, Joona Kiiski, Gary Linscott, 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)
+#ifndef PAWNS_H_INCLUDED
#define PAWNS_H_INCLUDED
-////
-//// Includes
-////
-
-#include "bitboard.h"
+#include "misc.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
-/// (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:
- Score pawns_value() const;
- Value kingside_storm_value(Color c) const;
- Value queenside_storm_value(Color c) 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;
+#include "types.h"
- template<Color Us>
- Score king_shelter(const Position& pos, Square ksq);
+namespace Pawns {
-private:
- template<Color Us>
- Score updateShelter(const Position& pos, Square ksq);
+/// Pawns::Entry contains various information about a pawn structure. A lookup
+/// to the pawn hash table (performed by calling the probe function) returns a
+/// pointer to an Entry object.
- Key key;
- Bitboard passedPawns[2];
- Bitboard pawnAttacks[2];
- Square kingSquares[2];
- Score value;
- int ksStormValue[2];
- int qsStormValue[2];
- int halfOpenFiles[2];
- Score kingShelters[2];
-};
+struct Entry {
-/// 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.
+ Score pawn_score(Color c) const { return scores[c]; }
+ Bitboard pawn_attacks(Color c) const { return pawnAttacks[c]; }
+ Bitboard passed_pawns(Color c) const { return passedPawns[c]; }
+ Bitboard pawn_attacks_span(Color c) const { return pawnAttacksSpan[c]; }
+ int weak_unopposed(Color c) const { return weakUnopposed[c]; }
+ int pawn_asymmetry() const { return asymmetry; }
+ int open_files() const { return openFiles; }
-class PawnInfoTable {
+ int semiopen_file(Color c, File f) const {
+ return semiopenFiles[c] & (1 << f);
+ }
- enum SideType { KingSide, QueenSide };
+ int pawns_on_same_color_squares(Color c, Square s) const {
+ return pawnsOnSquares[c][bool(DarkSquares & s)];
+ }
-public:
- PawnInfoTable();
- ~PawnInfoTable();
- PawnInfo* get_pawn_info(const Position& pos) const;
- void prefetch(Key key) const;
+ template<Color Us>
+ Score king_safety(const Position& pos) {
+ return kingSquares[Us] == pos.square<KING>(Us) && castlingRights[Us] == pos.can_castle(Us)
+ ? kingSafety[Us] : (kingSafety[Us] = do_king_safety<Us>(pos));
+ }
-private:
template<Color Us>
- Score evaluate_pawns(const Position& pos, Bitboard ourPawns, Bitboard theirPawns, PawnInfo* pi) const;
+ Score do_king_safety(const Position& pos);
- template<Color Us, SideType Side>
- int evaluate_pawn_storm(Square s, Rank r, File f, Bitboard theirPawns) const;
+ template<Color Us>
+ Value evaluate_shelter(const Position& pos, Square ksq);
- PawnInfo* entries;
+ Key key;
+ Score scores[COLOR_NB];
+ Bitboard passedPawns[COLOR_NB];
+ Bitboard pawnAttacks[COLOR_NB];
+ Bitboard pawnAttacksSpan[COLOR_NB];
+ Square kingSquares[COLOR_NB];
+ Score kingSafety[COLOR_NB];
+ int weakUnopposed[COLOR_NB];
+ int castlingRights[COLOR_NB];
+ int semiopenFiles[COLOR_NB];
+ int pawnsOnSquares[COLOR_NB][COLOR_NB]; // [color][light/dark squares]
+ int asymmetry;
+ int openFiles;
};
+typedef HashTable<Entry, 16384> Table;
-////
-//// 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 {
- return value;
-}
-
-inline Bitboard PawnInfo::pawn_attacks(Color c) const {
- return pawnAttacks[c];
-}
-
-inline Value PawnInfo::kingside_storm_value(Color c) const {
- return Value(ksStormValue[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 int PawnInfo::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 {
- return halfOpenFiles[c] & ((1 << int(f)) - 1);
-}
-
-inline int PawnInfo::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];
-}
+void init();
+Entry* probe(const Position& pos);
-template<Color Us>
-inline Score PawnInfo::king_shelter(const Position& pos, Square ksq) {
- return kingSquares[Us] == ksq ? kingShelters[Us] : updateShelter<Us>(pos, ksq);
-}
+} // namespace Pawns
-#endif // !defined(PAWNS_H_INCLUDED)
+#endif // #ifndef PAWNS_H_INCLUDED
projects / stockfish / blobdiff