X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.h;h=349005787fd402d6ab958818f46e1262fc4b8356;hp=2b9161250f5fb8277ba4f2deac1e012646cec331;hb=034a2b04f2fc1017721b4f3fc12895e5f8a190bd;hpb=374c9e6b63d0e233371ae38cc054d885f2117884 diff --git a/src/bitboard.h b/src/bitboard.h index 2b916125..34900578 100644 --- a/src/bitboard.h +++ b/src/bitboard.h @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2013 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 @@ -18,36 +18,72 @@ along with this program. If not, see . */ -#if !defined(BITBOARD_H_INCLUDED) +#ifndef BITBOARD_H_INCLUDED #define BITBOARD_H_INCLUDED #include "types.h" -CACHE_LINE_ALIGNMENT +namespace Bitboards { + +void init(); +void print(Bitboard b); + +} + +namespace Bitbases { -extern Bitboard RMasks[64]; -extern Bitboard RMagics[64]; -extern Bitboard* RAttacks[64]; -extern unsigned RShifts[64]; - -extern Bitboard BMasks[64]; -extern Bitboard BMagics[64]; -extern Bitboard* BAttacks[64]; -extern unsigned BShifts[64]; - -extern Bitboard SquareBB[64]; -extern Bitboard FileBB[8]; -extern Bitboard RankBB[8]; -extern Bitboard AdjacentFilesBB[8]; -extern Bitboard ThisAndAdjacentFilesBB[8]; -extern Bitboard InFrontBB[2][8]; -extern Bitboard StepAttacksBB[16][64]; -extern Bitboard BetweenBB[64][64]; -extern Bitboard SquaresInFrontMask[2][64]; -extern Bitboard PassedPawnMask[2][64]; -extern Bitboard AttackSpanMask[2][64]; -extern Bitboard PseudoAttacks[6][64]; +void init_kpk(); +bool probe_kpk(Square wksq, Square wpsq, Square bksq, Color us); +} + +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); + +CACHE_LINE_ALIGNMENT + +extern Bitboard RMasks[SQUARE_NB]; +extern Bitboard RMagics[SQUARE_NB]; +extern Bitboard* RAttacks[SQUARE_NB]; +extern unsigned RShifts[SQUARE_NB]; + +extern Bitboard BMasks[SQUARE_NB]; +extern Bitboard BMagics[SQUARE_NB]; +extern Bitboard* BAttacks[SQUARE_NB]; +extern unsigned BShifts[SQUARE_NB]; + +extern Bitboard SquareBB[SQUARE_NB]; +extern Bitboard FileBB[FILE_NB]; +extern Bitboard RankBB[RANK_NB]; +extern Bitboard AdjacentFilesBB[FILE_NB]; +extern Bitboard InFrontBB[COLOR_NB][RANK_NB]; +extern Bitboard StepAttacksBB[PIECE_NB][SQUARE_NB]; +extern Bitboard BetweenBB[SQUARE_NB][SQUARE_NB]; +extern Bitboard LineBB[SQUARE_NB][SQUARE_NB]; +extern Bitboard DistanceRingsBB[SQUARE_NB][8]; +extern Bitboard ForwardBB[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 int SquareDistance[SQUARE_NB][SQUARE_NB]; + +const Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL; /// 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. @@ -72,6 +108,34 @@ inline Bitboard operator^(Bitboard b, Square s) { return b ^ SquareBB[s]; } +inline bool more_than_one(Bitboard b) { + return b & (b - 1); +} + +inline int square_distance(Square s1, Square s2) { + return SquareDistance[s1][s2]; +} + +inline int file_distance(Square s1, Square s2) { + return abs(file_of(s1) - file_of(s2)); +} + +inline int rank_distance(Square s1, Square s2) { + return abs(rank_of(s1) - rank_of(s2)); +} + + +/// shift_bb() moves bitboard one step along direction Delta. Mainly for pawns. + +template +inline Bitboard shift_bb(Bitboard b) { + + return Delta == DELTA_N ? b << 8 : Delta == DELTA_S ? b >> 8 + : Delta == DELTA_NE ? (b & ~FileHBB) << 9 : Delta == DELTA_SE ? (b & ~FileHBB) >> 7 + : Delta == DELTA_NW ? (b & ~FileABB) << 7 : Delta == DELTA_SW ? (b & ~FileABB) >> 9 + : 0; +} + /// rank_bb() and file_bb() take a file or a square as input and return /// a bitboard representing all squares on the given file or rank. @@ -93,7 +157,7 @@ inline Bitboard file_bb(Square s) { } -/// adjacent_files_bb takes a file as input and returns a bitboard representing +/// adjacent_files_bb() takes a file as input and returns a bitboard representing /// all squares on the adjacent files. inline Bitboard adjacent_files_bb(File f) { @@ -101,178 +165,174 @@ inline Bitboard adjacent_files_bb(File f) { } -/// this_and_adjacent_files_bb takes a file as input and returns a bitboard -/// representing all squares on the given and adjacent files. - -inline Bitboard this_and_adjacent_files_bb(File f) { - return ThisAndAdjacentFilesBB[f]; -} - - -/// in_front_bb() takes a color and a rank or square as input, and returns a -/// bitboard representing all the squares on all ranks in front of the rank -/// (or square), from the given color's point of view. For instance, -/// in_front_bb(WHITE, RANK_5) will give all squares on ranks 6, 7 and 8, while -/// in_front_bb(BLACK, SQ_D3) will give all squares on ranks 1 and 2. +/// in_front_bb() takes a color and a rank as input, and returns a bitboard +/// representing all the squares on all ranks in front of the rank, from the +/// given color's point of view. For instance, in_front_bb(BLACK, RANK_3) will +/// give all squares on ranks 1 and 2. inline Bitboard in_front_bb(Color c, Rank r) { return InFrontBB[c][r]; } -inline Bitboard in_front_bb(Color c, Square s) { - return InFrontBB[c][rank_of(s)]; -} +/// between_bb() returns a bitboard representing all squares between two squares. +/// 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 line, file or diagonal, +/// 0 is returned. -/// Functions for computing sliding attack bitboards. Function attacks_bb() takes -/// a square and a bitboard of occupied squares as input, and returns a bitboard -/// representing all squares attacked by Pt (bishop or rook) on the given square. -template -FORCE_INLINE unsigned magic_index(Square s, Bitboard occ) { - - Bitboard* const Masks = Pt == ROOK ? RMasks : BMasks; - Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics; - unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts; - - if (Is64Bit) - return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[s]); - - unsigned lo = unsigned(occ) & unsigned(Masks[s]); - unsigned hi = unsigned(occ >> 32) & unsigned(Masks[s] >> 32); - return (lo * unsigned(Magics[s]) ^ hi * unsigned(Magics[s] >> 32)) >> Shifts[s]; -} - -template -inline Bitboard attacks_bb(Square s, Bitboard occ) { - Bitboard** const Attacks = Pt == ROOK ? RAttacks : BAttacks; - return Attacks[s][magic_index(s, occ)]; +inline Bitboard between_bb(Square s1, Square s2) { + return BetweenBB[s1][s2]; } -/// squares_between returns a bitboard representing all squares between -/// two squares. For instance, squares_between(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 line, file or diagonal, EmptyBoardBB is returned. +/// forward_bb() takes a color and a square as input, and returns a bitboard +/// representing all squares along the line in front of the square, from the +/// point of view of the given color. Definition of the table is: +/// ForwardBB[c][s] = in_front_bb(c, s) & file_bb(s) -inline Bitboard squares_between(Square s1, Square s2) { - return BetweenBB[s1][s2]; +inline Bitboard forward_bb(Color c, Square s) { + return ForwardBB[c][s]; } -/// squares_in_front_of takes a color and a square as input, and returns a -/// bitboard representing all squares along the line in front of the square, -/// from the point of view of the given color. Definition of the table is: -/// SquaresInFrontOf[c][s] = in_front_bb(c, s) & file_bb(s) +/// pawn_attack_span() takes a color and a square as input, and returns a bitboard +/// representing all squares that can be attacked by a pawn of the given color +/// when it moves along its file starting from the given square. Definition is: +/// PawnAttackSpan[c][s] = in_front_bb(c, s) & adjacent_files_bb(s); -inline Bitboard squares_in_front_of(Color c, Square s) { - return SquaresInFrontMask[c][s]; +inline Bitboard pawn_attack_span(Color c, Square s) { + return PawnAttackSpan[c][s]; } -/// passed_pawn_mask takes a color and a square as input, and returns a +/// passed_pawn_mask() takes a color and a square as input, and returns a /// bitboard mask which can be used to test if a pawn of the given color on /// the given square is a passed pawn. Definition of the table is: -/// PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_adjacent_files_bb(s) +/// PassedPawnMask[c][s] = pawn_attack_span(c, s) | forward_bb(c, s) inline Bitboard passed_pawn_mask(Color c, Square s) { return PassedPawnMask[c][s]; } -/// attack_span_mask takes a color and a square as input, and returns a bitboard -/// representing all squares that can be attacked by a pawn of the given color -/// when it moves along its file starting from the given square. Definition is: -/// AttackSpanMask[c][s] = in_front_bb(c, s) & adjacent_files_bb(s); +/// squares_of_color() returns a bitboard representing all squares with the same +/// color of the given square. -inline Bitboard attack_span_mask(Color c, Square s) { - return AttackSpanMask[c][s]; +inline Bitboard squares_of_color(Square s) { + return DarkSquares & s ? DarkSquares : ~DarkSquares; } -/// squares_aligned returns true if the squares s1, s2 and s3 are aligned +/// aligned() returns true if the squares s1, s2 and s3 are aligned /// either on a straight or on a diagonal line. -inline bool squares_aligned(Square s1, Square s2, Square s3) { - return (BetweenBB[s1][s2] | BetweenBB[s1][s3] | BetweenBB[s2][s3]) - & ( SquareBB[s1] | SquareBB[s2] | SquareBB[s3]); +inline bool aligned(Square s1, Square s2, Square s3) { + return LineBB[s1][s2] & s3; } -/// same_color_squares() returns a bitboard representing all squares with -/// the same color of the given square. +/// Functions for computing sliding attack bitboards. Function attacks_bb() takes +/// a square and a bitboard of occupied squares as input, and returns a bitboard +/// representing all squares attacked by Pt (bishop or rook) on the given square. +template +FORCE_INLINE unsigned magic_index(Square s, Bitboard occ) { -inline Bitboard same_color_squares(Square s) { - return Bitboard(0xAA55AA55AA55AA55ULL) & s ? 0xAA55AA55AA55AA55ULL - : ~0xAA55AA55AA55AA55ULL; + Bitboard* const Masks = Pt == ROOK ? RMasks : BMasks; + Bitboard* const Magics = Pt == ROOK ? RMagics : BMagics; + unsigned* const Shifts = Pt == ROOK ? RShifts : BShifts; + + if (Is64Bit) + return unsigned(((occ & Masks[s]) * Magics[s]) >> Shifts[s]); + + unsigned lo = unsigned(occ) & unsigned(Masks[s]); + unsigned hi = unsigned(occ >> 32) & unsigned(Masks[s] >> 32); + return (lo * unsigned(Magics[s]) ^ hi * unsigned(Magics[s] >> 32)) >> Shifts[s]; } +template +inline Bitboard attacks_bb(Square s, Bitboard occ) { + return (Pt == ROOK ? RAttacks : BAttacks)[s][magic_index(s, occ)]; +} -/// single_bit() returns true if in the 'b' bitboard is set a single bit (or if -/// b == 0). +inline Bitboard attacks_bb(Piece p, Square s, Bitboard occ) { -inline bool single_bit(Bitboard b) { - return !(b & (b - 1)); + switch (type_of(p)) + { + case BISHOP: return attacks_bb(s, occ); + case ROOK : return attacks_bb(s, occ); + case QUEEN : return attacks_bb(s, occ) | attacks_bb(s, occ); + default : return StepAttacksBB[p][s]; + } } -/// first_1() finds the least significant nonzero bit in a nonzero bitboard. -/// pop_1st_bit() finds and clears the least significant nonzero bit in a -/// nonzero bitboard. +/// lsb()/msb() finds the least/most significant bit in a nonzero bitboard. +/// pop_lsb() finds and clears the least significant bit in a nonzero bitboard. -#if defined(USE_BSFQ) +#ifdef USE_BSFQ -#if defined(_MSC_VER) && !defined(__INTEL_COMPILER) +# if defined(_MSC_VER) && !defined(__INTEL_COMPILER) -FORCE_INLINE Square first_1(Bitboard b) { +FORCE_INLINE Square lsb(Bitboard b) { unsigned long index; _BitScanForward64(&index, b); return (Square) index; } -FORCE_INLINE Square last_1(Bitboard b) { +FORCE_INLINE Square msb(Bitboard b) { unsigned long index; _BitScanReverse64(&index, b); return (Square) index; } -#else -FORCE_INLINE Square first_1(Bitboard b) { // Assembly code by Heinz van Saanen - Bitboard dummy; - __asm__("bsfq %1, %0": "=r"(dummy): "rm"(b) ); - return (Square) dummy; +# elif defined(__arm__) + +FORCE_INLINE int lsb32(uint32_t v) { + __asm__("rbit %0, %1" : "=r"(v) : "r"(v)); + return __builtin_clz(v); } -FORCE_INLINE Square last_1(Bitboard b) { - Bitboard dummy; - __asm__("bsrq %1, %0": "=r"(dummy): "rm"(b) ); - return (Square) dummy; +FORCE_INLINE Square msb(Bitboard b) { + return (Square) (63 - __builtin_clzll(b)); } -#endif -FORCE_INLINE Square pop_1st_bit(Bitboard* b) { - const Square s = first_1(*b); - *b &= ~(1ULL<> 32))); } -#else // if !defined(USE_BSFQ) +# else -extern Square first_1(Bitboard b); -extern Square last_1(Bitboard b); -extern Square pop_1st_bit(Bitboard* b); +FORCE_INLINE Square lsb(Bitboard b) { // Assembly code by Heinz van Saanen + Bitboard index; + __asm__("bsfq %1, %0": "=r"(index): "rm"(b) ); + return (Square) index; +} -#endif +FORCE_INLINE Square msb(Bitboard b) { + Bitboard index; + __asm__("bsrq %1, %0": "=r"(index): "rm"(b) ); + return (Square) index; +} -// relative_rank() returns the relative rank of the closest bit set on the Bitboard. -// Only to be used with bitboards that contain a single file. +# endif -template -inline Rank relative_rank(Bitboard b) { - Square s = Us == WHITE ? first_1(b) - : ~last_1(b); - return rank_of(s); +FORCE_INLINE Square pop_lsb(Bitboard* b) { + const Square s = lsb(*b); + *b &= *b - 1; + return s; } -extern void print_bitboard(Bitboard b); -extern void bitboards_init(); +#else // if defined(USE_BSFQ) + +extern Square msb(Bitboard b); +extern Square lsb(Bitboard b); +extern Square pop_lsb(Bitboard* b); + +#endif + +/// frontmost_sq() and backmost_sq() find the square corresponding to the +/// most/least advanced bit relative to the given color. + +inline Square frontmost_sq(Color c, Bitboard b) { return c == WHITE ? msb(b) : lsb(b); } +inline Square backmost_sq(Color c, Bitboard b) { return c == WHITE ? lsb(b) : msb(b); } -#endif // !defined(BITBOARD_H_INCLUDED) +#endif // #ifndef BITBOARD_H_INCLUDED