X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.h;h=6f99ef1953bf9fe702e16731fdd13915359eec29;hp=37585bb19b18e8e25feb54120429b3177caa6da6;hb=f21b50398231b4846c364e23bfeeab314c7731ea;hpb=090e49547ecaba8c9ec696d75f2fca3020bb058a diff --git a/src/bitboard.h b/src/bitboard.h index 37585bb1..6f99ef19 100644 --- a/src/bitboard.h +++ b/src/bitboard.h @@ -60,21 +60,20 @@ constexpr Bitboard Rank6BB = Rank1BB << (8 * 5); constexpr Bitboard Rank7BB = Rank1BB << (8 * 6); constexpr Bitboard Rank8BB = Rank1BB << (8 * 7); -extern int SquareDistance[SQUARE_NB][SQUARE_NB]; +constexpr Bitboard QueenSide = FileABB | FileBBB | FileCBB | FileDBB; +constexpr Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB; +constexpr Bitboard KingSide = FileEBB | FileFBB | FileGBB | FileHBB; +constexpr Bitboard Center = (FileDBB | FileEBB) & (Rank4BB | Rank5BB); + +extern uint8_t PopCnt16[1 << 16]; +extern uint8_t SquareDistance[SQUARE_NB][SQUARE_NB]; -extern Bitboard SquareBB[SQUARE_NB]; -extern Bitboard FileBB[FILE_NB]; -extern Bitboard RankBB[RANK_NB]; -extern Bitboard AdjacentFilesBB[FILE_NB]; -extern Bitboard ForwardRanksBB[COLOR_NB][RANK_NB]; -extern Bitboard BetweenBB[SQUARE_NB][SQUARE_NB]; extern Bitboard LineBB[SQUARE_NB][SQUARE_NB]; extern Bitboard DistanceRingBB[SQUARE_NB][8]; -extern Bitboard ForwardFileBB[COLOR_NB][SQUARE_NB]; -extern Bitboard PassedPawnMask[COLOR_NB][SQUARE_NB]; -extern Bitboard PawnAttackSpan[COLOR_NB][SQUARE_NB]; extern Bitboard PseudoAttacks[PIECE_TYPE_NB][SQUARE_NB]; extern Bitboard PawnAttacks[COLOR_NB][SQUARE_NB]; +extern Bitboard KingFlank[FILE_NB]; +extern Bitboard SquareBB[SQUARE_NB]; /// Magic holds all magic bitboards relevant data for a single square @@ -102,64 +101,50 @@ struct Magic { extern Magic RookMagics[SQUARE_NB]; extern Magic BishopMagics[SQUARE_NB]; - -/// Overloads of bitwise operators between a Bitboard and a Square for testing -/// whether a given bit is set in a bitboard, and for setting and clearing bits. - -inline Bitboard operator&(Bitboard b, Square s) { - assert(s >= SQ_A1 && s <= SQ_H8); - return b & SquareBB[s]; -} - -inline Bitboard operator|(Bitboard b, Square s) { - assert(s >= SQ_A1 && s <= SQ_H8); - return b | SquareBB[s]; -} - -inline Bitboard operator^(Bitboard b, Square s) { +inline Bitboard square_bb(Square s) { assert(s >= SQ_A1 && s <= SQ_H8); - return b ^ SquareBB[s]; + return SquareBB[s]; } -inline Bitboard& operator|=(Bitboard& b, Square s) { - assert(s >= SQ_A1 && s <= SQ_H8); - return b |= SquareBB[s]; -} +/// Overloads of bitwise operators between a Bitboard and a Square for testing +/// whether a given bit is set in a bitboard, and for setting and clearing bits. -inline Bitboard& operator^=(Bitboard& b, Square s) { - assert(s >= SQ_A1 && s <= SQ_H8); - return b ^= SquareBB[s]; -} +inline Bitboard operator&( Bitboard b, Square s) { return b & square_bb(s); } +inline Bitboard operator|( Bitboard b, Square s) { return b | square_bb(s); } +inline Bitboard operator^( Bitboard b, Square s) { return b ^ square_bb(s); } +inline Bitboard& operator|=(Bitboard& b, Square s) { return b |= square_bb(s); } +inline Bitboard& operator^=(Bitboard& b, Square s) { return b ^= square_bb(s); } constexpr bool more_than_one(Bitboard b) { return b & (b - 1); } inline bool opposite_colors(Square s1, Square s2) { - return (bool(DarkSquares & s1) != bool(DarkSquares & s2)); + return bool(DarkSquares & s1) != bool(DarkSquares & s2); } + /// rank_bb() and file_bb() return a bitboard representing all the squares on /// the given file or rank. inline Bitboard rank_bb(Rank r) { - return RankBB[r]; + return Rank1BB << (8 * r); } inline Bitboard rank_bb(Square s) { - return RankBB[rank_of(s)]; + return rank_bb(rank_of(s)); } inline Bitboard file_bb(File f) { - return FileBB[f]; + return FileABB << f; } inline Bitboard file_bb(Square s) { - return FileBB[file_of(s)]; + return file_bb(file_of(s)); } -/// shift() moves a bitboard one step along direction D (mainly for pawns) +/// shift() moves a bitboard one step along direction D template constexpr Bitboard shift(Bitboard b) { @@ -171,8 +156,8 @@ constexpr Bitboard shift(Bitboard b) { } -/// pawn_attacks_bb() returns the pawn attacks for the given color from the -/// squares in the given bitboard. +/// pawn_attacks_bb() returns the squares attacked by pawns of the given color +/// from the squares in the given bitboard. template constexpr Bitboard pawn_attacks_bb(Bitboard b) { @@ -181,11 +166,11 @@ constexpr Bitboard pawn_attacks_bb(Bitboard b) { } -/// double_pawn_attacks_bb() returns the pawn attacks for the given color -/// from the squares in the given bitboard. +/// pawn_double_attacks_bb() returns the squares doubly attacked by pawns of the +/// given color from the squares in the given bitboard. template -constexpr Bitboard double_pawn_attacks_bb(Bitboard b) { +constexpr Bitboard pawn_double_attacks_bb(Bitboard b) { return C == WHITE ? shift(b) & shift(b) : shift(b) & shift(b); } @@ -195,54 +180,51 @@ constexpr Bitboard double_pawn_attacks_bb(Bitboard b) { /// adjacent files of the given one. inline Bitboard adjacent_files_bb(File f) { - return AdjacentFilesBB[f]; + return shift(file_bb(f)) | shift(file_bb(f)); } -/// between_bb() returns a bitboard representing all the squares between the two -/// given ones. For instance, between_bb(SQ_C4, SQ_F7) returns a bitboard with -/// the bits for square d5 and e6 set. If s1 and s2 are not on the same rank, file -/// or diagonal, 0 is returned. +/// between_bb() returns squares that are linearly between the given squares +/// If the given squares are not on a same file/rank/diagonal, return 0. inline Bitboard between_bb(Square s1, Square s2) { - return BetweenBB[s1][s2]; + return LineBB[s1][s2] & ( (AllSquares << (s1 + (s1 < s2))) + ^(AllSquares << (s2 + !(s1 < s2)))); } -/// forward_ranks_bb() returns a bitboard representing the squares on all the ranks +/// forward_ranks_bb() returns a bitboard representing the squares on the ranks /// in front of the given one, from the point of view of the given color. For instance, /// forward_ranks_bb(BLACK, SQ_D3) will return the 16 squares on ranks 1 and 2. inline Bitboard forward_ranks_bb(Color c, Square s) { - return ForwardRanksBB[c][rank_of(s)]; + return c == WHITE ? ~Rank1BB << 8 * (rank_of(s) - RANK_1) + : ~Rank8BB >> 8 * (RANK_8 - rank_of(s)); } -/// forward_file_bb() returns a bitboard representing all the squares along the line -/// in front of the given one, from the point of view of the given color: -/// ForwardFileBB[c][s] = forward_ranks_bb(c, s) & file_bb(s) +/// forward_file_bb() returns a bitboard representing all the squares along the +/// line in front of the given one, from the point of view of the given color. inline Bitboard forward_file_bb(Color c, Square s) { - return ForwardFileBB[c][s]; + return forward_ranks_bb(c, s) & file_bb(s); } -/// pawn_attack_span() returns a bitboard representing all the squares that can be -/// attacked by a pawn of the given color when it moves along its file, starting -/// from the given square: -/// PawnAttackSpan[c][s] = forward_ranks_bb(c, s) & adjacent_files_bb(file_of(s)); +/// pawn_attack_span() returns a bitboard representing all the squares that can +/// be attacked by a pawn of the given color when it moves along its file, +/// starting from the given square. inline Bitboard pawn_attack_span(Color c, Square s) { - return PawnAttackSpan[c][s]; + return forward_ranks_bb(c, s) & adjacent_files_bb(file_of(s)); } -/// passed_pawn_mask() returns a bitboard mask which can be used to test if a -/// pawn of the given color and on the given square is a passed pawn: -/// PassedPawnMask[c][s] = pawn_attack_span(c, s) | forward_file_bb(c, s) +/// passed_pawn_span() returns a bitboard which can be used to test if a pawn of +/// the given color and on the given square is a passed pawn. -inline Bitboard passed_pawn_mask(Color c, Square s) { - return PassedPawnMask[c][s]; +inline Bitboard passed_pawn_span(Color c, Square s) { + return forward_ranks_bb(c, s) & (adjacent_files_bb(file_of(s)) | file_bb(s)); } @@ -255,15 +237,16 @@ inline bool aligned(Square s1, Square s2, Square s3) { /// distance() functions return the distance between x and y, defined as the -/// number of steps for a king in x to reach y. Works with squares, ranks, files. +/// number of steps for a king in x to reach y. -template inline int distance(T x, T y) { return x < y ? y - x : x - y; } +template inline int distance(Square x, Square y); +template<> inline int distance(Square x, Square y) { return std::abs(file_of(x) - file_of(y)); } +template<> inline int distance(Square x, Square y) { return std::abs(rank_of(x) - rank_of(y)); } template<> inline int distance(Square x, Square y) { return SquareDistance[x][y]; } -template inline int distance(T2 x, T2 y); -template<> inline int distance(Square x, Square y) { return distance(file_of(x), file_of(y)); } -template<> inline int distance(Square x, Square y) { return distance(rank_of(x), rank_of(y)); } - +template constexpr const T& clamp(const T& v, const T& lo, const T& hi) { + return v < lo ? lo : v > hi ? hi : v; +} /// attacks_bb() returns a bitboard representing all the squares attacked by a /// piece of type Pt (bishop or rook) placed on 's'. @@ -295,7 +278,6 @@ inline int popcount(Bitboard b) { #ifndef USE_POPCNT - extern uint8_t PopCnt16[1 << 16]; union { Bitboard bb; uint16_t u[4]; } v = { b }; return PopCnt16[v.u[0]] + PopCnt16[v.u[1]] + PopCnt16[v.u[2]] + PopCnt16[v.u[3]];