X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.h;h=b1d961f4d9fc2b018a9084e66510004b7594a779;hp=ba1b0072bce5079064b5f59cbe26328cb7b6dc03;hb=f98c77413b68d506977bc078de7a47455968a926;hpb=28b6a457c24d9202ba43a6d6703221250f0f8749 diff --git a/src/bitboard.h b/src/bitboard.h index ba1b0072..b1d961f4 100644 --- a/src/bitboard.h +++ b/src/bitboard.h @@ -2,7 +2,7 @@ Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad - Copyright (C) 2015-2017 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad + Copyright (C) 2015-2019 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 @@ -39,42 +39,41 @@ const std::string pretty(Bitboard b); } -const Bitboard AllSquares = ~Bitboard(0); -const Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL; - -const Bitboard FileABB = 0x0101010101010101ULL; -const Bitboard FileBBB = FileABB << 1; -const Bitboard FileCBB = FileABB << 2; -const Bitboard FileDBB = FileABB << 3; -const Bitboard FileEBB = FileABB << 4; -const Bitboard FileFBB = FileABB << 5; -const Bitboard FileGBB = FileABB << 6; -const Bitboard FileHBB = FileABB << 7; - -const Bitboard Rank1BB = 0xFF; -const Bitboard Rank2BB = Rank1BB << (8 * 1); -const Bitboard Rank3BB = Rank1BB << (8 * 2); -const Bitboard Rank4BB = Rank1BB << (8 * 3); -const Bitboard Rank5BB = Rank1BB << (8 * 4); -const Bitboard Rank6BB = Rank1BB << (8 * 5); -const Bitboard Rank7BB = Rank1BB << (8 * 6); -const Bitboard Rank8BB = Rank1BB << (8 * 7); - -extern int SquareDistance[SQUARE_NB][SQUARE_NB]; +constexpr Bitboard AllSquares = ~Bitboard(0); +constexpr Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL; + +constexpr Bitboard FileABB = 0x0101010101010101ULL; +constexpr Bitboard FileBBB = FileABB << 1; +constexpr Bitboard FileCBB = FileABB << 2; +constexpr Bitboard FileDBB = FileABB << 3; +constexpr Bitboard FileEBB = FileABB << 4; +constexpr Bitboard FileFBB = FileABB << 5; +constexpr Bitboard FileGBB = FileABB << 6; +constexpr Bitboard FileHBB = FileABB << 7; + +constexpr Bitboard Rank1BB = 0xFF; +constexpr Bitboard Rank2BB = Rank1BB << (8 * 1); +constexpr Bitboard Rank3BB = Rank1BB << (8 * 2); +constexpr Bitboard Rank4BB = Rank1BB << (8 * 3); +constexpr Bitboard Rank5BB = Rank1BB << (8 * 4); +constexpr Bitboard Rank6BB = Rank1BB << (8 * 5); +constexpr Bitboard Rank7BB = Rank1BB << (8 * 6); +constexpr Bitboard Rank8BB = Rank1BB << (8 * 7); + +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 @@ -102,118 +101,130 @@ struct Magic { extern Magic RookMagics[SQUARE_NB]; extern Magic BishopMagics[SQUARE_NB]; +inline Bitboard square_bb(Square s) { + assert(s >= SQ_A1 && s <= SQ_H8); + return 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) { - return b & SquareBB[s]; -} - -inline Bitboard operator|(Bitboard b, Square s) { - return b | SquareBB[s]; -} - -inline Bitboard operator^(Bitboard b, Square s) { - return b ^ SquareBB[s]; -} - -inline Bitboard& operator|=(Bitboard& b, Square s) { - return b |= SquareBB[s]; -} - -inline Bitboard& operator^=(Bitboard& b, Square s) { - 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); +} + /// 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 +template constexpr Bitboard shift(Bitboard b) { return D == NORTH ? b << 8 : D == SOUTH ? b >> 8 - : D == NORTH_EAST ? (b & ~FileHBB) << 9 : D == SOUTH_EAST ? (b & ~FileHBB) >> 7 - : D == NORTH_WEST ? (b & ~FileABB) << 7 : D == SOUTH_WEST ? (b & ~FileABB) >> 9 + : D == EAST ? (b & ~FileHBB) << 1 : D == WEST ? (b & ~FileABB) >> 1 + : D == NORTH_EAST ? (b & ~FileHBB) << 9 : D == NORTH_WEST ? (b & ~FileABB) << 7 + : D == SOUTH_EAST ? (b & ~FileHBB) >> 7 : D == SOUTH_WEST ? (b & ~FileABB) >> 9 : 0; } +/// 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) { + return C == WHITE ? shift(b) | shift(b) + : shift(b) | shift(b); +} + + +/// 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 pawn_double_attacks_bb(Bitboard b) { + return C == WHITE ? shift(b) & shift(b) + : shift(b) & shift(b); +} + + /// adjacent_files_bb() returns a bitboard representing all the squares on the /// 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 all the squares on all 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. +/// 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)); } @@ -228,13 +239,16 @@ 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. -template inline int distance(T x, T y) { return x < y ? y - x : x - y; } +template inline int distance(T x, T y) { return std::abs(x - 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'. @@ -266,7 +280,6 @@ 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]]; @@ -284,7 +297,7 @@ inline int popcount(Bitboard b) { /// lsb() and msb() return the least/most significant bit in a non-zero bitboard -#if defined(__GNUC__) +#if defined(__GNUC__) // GCC, Clang, ICC inline Square lsb(Bitboard b) { assert(b); @@ -296,7 +309,9 @@ inline Square msb(Bitboard b) { return Square(63 ^ __builtin_clzll(b)); } -#elif defined(_WIN64) && defined(_MSC_VER) +#elif defined(_MSC_VER) // MSVC + +#ifdef _WIN64 // MSVC, WIN64 inline Square lsb(Bitboard b) { assert(b); @@ -312,12 +327,39 @@ inline Square msb(Bitboard b) { return (Square) idx; } -#else +#else // MSVC, WIN32 + +inline Square lsb(Bitboard b) { + assert(b); + unsigned long idx; + + if (b & 0xffffffff) { + _BitScanForward(&idx, int32_t(b)); + return Square(idx); + } else { + _BitScanForward(&idx, int32_t(b >> 32)); + return Square(idx + 32); + } +} + +inline Square msb(Bitboard b) { + assert(b); + unsigned long idx; + + if (b >> 32) { + _BitScanReverse(&idx, int32_t(b >> 32)); + return Square(idx + 32); + } else { + _BitScanReverse(&idx, int32_t(b)); + return Square(idx); + } +} + +#endif -#define NO_BSF // Fallback on software implementation for other cases +#else // Compiler is neither GCC nor MSVC compatible -Square lsb(Bitboard b); -Square msb(Bitboard b); +#error "Compiler not supported." #endif