/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2009 Marco Costalba
+ Copyright (C) 2008-2012 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
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-
#if !defined(BITBOARD_H_INCLUDED)
#define BITBOARD_H_INCLUDED
-////
-//// Includes
-////
-
-#include "direction.h"
-#include "piece.h"
-#include "square.h"
#include "types.h"
-
-////
-//// Constants and variables
-////
-
-const Bitboard EmptyBoardBB = 0ULL;
-
-const Bitboard WhiteSquaresBB = 0x55AA55AA55AA55AAULL;
-const Bitboard BlackSquaresBB = 0xAA55AA55AA55AA55ULL;
-const Bitboard SquaresByColorBB[2] = { BlackSquaresBB, WhiteSquaresBB };
-
-const Bitboard FileABB = 0x0101010101010101ULL;
-const Bitboard FileBBB = 0x0202020202020202ULL;
-const Bitboard FileCBB = 0x0404040404040404ULL;
-const Bitboard FileDBB = 0x0808080808080808ULL;
-const Bitboard FileEBB = 0x1010101010101010ULL;
-const Bitboard FileFBB = 0x2020202020202020ULL;
-const Bitboard FileGBB = 0x4040404040404040ULL;
-const Bitboard FileHBB = 0x8080808080808080ULL;
-
-const Bitboard FileBB[8] = {
- FileABB, FileBBB, FileCBB, FileDBB, FileEBB, FileFBB, FileGBB, FileHBB
-};
-
-const Bitboard NeighboringFilesBB[8] = {
- FileBBB, FileABB|FileCBB, FileBBB|FileDBB, FileCBB|FileEBB,
- FileDBB|FileFBB, FileEBB|FileGBB, FileFBB|FileHBB, FileGBB
-};
-
-const Bitboard ThisAndNeighboringFilesBB[8] = {
- FileABB|FileBBB, FileABB|FileBBB|FileCBB,
- FileBBB|FileCBB|FileDBB, FileCBB|FileDBB|FileEBB,
- FileDBB|FileEBB|FileFBB, FileEBB|FileFBB|FileGBB,
- FileFBB|FileGBB|FileHBB, FileGBB|FileHBB
-};
-
-const Bitboard Rank1BB = 0xFFULL;
-const Bitboard Rank2BB = 0xFF00ULL;
-const Bitboard Rank3BB = 0xFF0000ULL;
-const Bitboard Rank4BB = 0xFF000000ULL;
-const Bitboard Rank5BB = 0xFF00000000ULL;
-const Bitboard Rank6BB = 0xFF0000000000ULL;
-const Bitboard Rank7BB = 0xFF000000000000ULL;
-const Bitboard Rank8BB = 0xFF00000000000000ULL;
-
-const Bitboard RankBB[8] = {
- Rank1BB, Rank2BB, Rank3BB, Rank4BB, Rank5BB, Rank6BB, Rank7BB, Rank8BB
-};
-
-const Bitboard RelativeRankBB[2][8] = {
- { Rank1BB, Rank2BB, Rank3BB, Rank4BB, Rank5BB, Rank6BB, Rank7BB, Rank8BB },
- { Rank8BB, Rank7BB, Rank6BB, Rank5BB, Rank4BB, Rank3BB, Rank2BB, Rank1BB }
-};
-
-const Bitboard InFrontBB[2][8] = {
- { Rank2BB | Rank3BB | Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB,
- Rank3BB | Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB,
- Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB,
- Rank5BB | Rank6BB | Rank7BB | Rank8BB,
- Rank6BB | Rank7BB | Rank8BB,
- Rank7BB | Rank8BB,
- Rank8BB,
- EmptyBoardBB
- },
- { EmptyBoardBB,
- Rank1BB,
- Rank2BB | Rank1BB,
- Rank3BB | Rank2BB | Rank1BB,
- Rank4BB | Rank3BB | Rank2BB | Rank1BB,
- Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB,
- Rank6BB | Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB,
- Rank7BB | Rank6BB | Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB
- }
-};
+extern Bitboard FileBB[8];
+extern Bitboard AdjacentFilesBB[8];
+extern Bitboard ThisAndAdjacentFilesBB[8];
+extern Bitboard RankBB[8];
+extern Bitboard InFrontBB[2][8];
extern Bitboard SetMaskBB[65];
extern Bitboard ClearMaskBB[65];
-extern Bitboard StepAttackBB[16][64];
-extern Bitboard RayBB[64][8];
+extern Bitboard StepAttacksBB[16][64];
extern Bitboard BetweenBB[64][64];
+extern Bitboard SquaresInFrontMask[2][64];
extern Bitboard PassedPawnMask[2][64];
-extern Bitboard OutpostMask[2][64];
+extern Bitboard AttackSpanMask[2][64];
-extern const uint64_t RMult[64];
-extern const int RShift[64];
-extern Bitboard RMask[64];
-extern int RAttackIndex[64];
-extern Bitboard RAttacks[0x19000];
+extern uint64_t RMagics[64];
+extern int RShifts[64];
+extern Bitboard RMasks[64];
+extern Bitboard* RAttacks[64];
-extern const uint64_t BMult[64];
-extern const int BShift[64];
-extern Bitboard BMask[64];
-extern int BAttackIndex[64];
-extern Bitboard BAttacks[0x1480];
+extern uint64_t BMagics[64];
+extern int BShifts[64];
+extern Bitboard BMasks[64];
+extern Bitboard* BAttacks[64];
-extern Bitboard BishopPseudoAttacks[64];
-extern Bitboard RookPseudoAttacks[64];
-extern Bitboard QueenPseudoAttacks[64];
+extern Bitboard PseudoAttacks[6][64];
+extern uint8_t BitCount8Bit[256];
-////
-//// Inline functions
-////
/// Functions for testing whether a given bit is set in a bitboard, and for
/// setting and clearing bits.
return b & SetMaskBB[s];
}
-inline void set_bit(Bitboard *b, Square s) {
+inline void set_bit(Bitboard* b, Square s) {
*b |= SetMaskBB[s];
}
-inline void clear_bit(Bitboard *b, Square s) {
+inline void clear_bit(Bitboard* b, Square s) {
*b &= ClearMaskBB[s];
}
return SetMaskBB[from] | SetMaskBB[to];
}
-inline void do_move_bb(Bitboard *b, Bitboard move_bb) {
+inline void do_move_bb(Bitboard* b, Bitboard move_bb) {
*b ^= move_bb;
}
-/// rank_bb() and file_bb() gives a bitboard containing all squares on a given
-/// file or rank. It is also possible to pass a square as input to these
-/// functions.
+
+/// 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.
inline Bitboard rank_bb(Rank r) {
return RankBB[r];
}
inline Bitboard rank_bb(Square s) {
- return rank_bb(square_rank(s));
+ return RankBB[rank_of(s)];
}
inline Bitboard file_bb(File f) {
}
inline Bitboard file_bb(Square s) {
- return file_bb(square_file(s));
-}
-
-
-/// neighboring_files_bb takes a file or a square as input, and returns a
-/// bitboard representing all squares on the neighboring files.
-
-inline Bitboard neighboring_files_bb(File f) {
- return NeighboringFilesBB[f];
-}
-
-inline Bitboard neighboring_files_bb(Square s) {
- return neighboring_files_bb(square_file(s));
+ return FileBB[file_of(s)];
}
-/// this_and_neighboring_files_bb takes a file or a square as input, and
-/// returns a bitboard representing all squares on the given and neighboring
-/// files.
+/// adjacent_files_bb takes a file as input and returns a bitboard representing
+/// all squares on the adjacent files.
-inline Bitboard this_and_neighboring_files_bb(File f) {
- return ThisAndNeighboringFilesBB[f];
-}
-
-inline Bitboard this_and_neighboring_files_bb(Square s) {
- return this_and_neighboring_files_bb(square_file(s));
+inline Bitboard adjacent_files_bb(File f) {
+ return AdjacentFilesBB[f];
}
-/// relative_rank_bb() takes a color and a rank as input, and returns a bitboard
-/// representing all squares on the given rank from the given color's point of
-/// view. For instance, relative_rank_bb(WHITE, 7) gives all squares on the
-/// 7th rank, while relative_rank_bb(BLACK, 7) gives all squares on the 2nd
-/// rank.
+/// 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 relative_rank_bb(Color c, Rank r) {
- return RelativeRankBB[c][r];
+inline Bitboard this_and_adjacent_files_bb(File f) {
+ return ThisAndAdjacentFilesBB[f];
}
}
inline Bitboard in_front_bb(Color c, Square s) {
- return in_front_bb(c, square_rank(s));
-}
-
-
-/// behind_bb() takes a color and a rank or square as input, and returns a
-/// bitboard representing all the squares on all ranks behind of the rank
-/// (or square), from the given color's point of view.
-
-inline Bitboard behind_bb(Color c, Rank r) {
- return InFrontBB[opposite_color(c)][r];
-}
-
-inline Bitboard behind_bb(Color c, Square s) {
- return in_front_bb(opposite_color(c), square_rank(s));
-}
-
-
-/// ray_bb() gives a bitboard representing all squares along the ray in a
-/// given direction from a given square.
-
-inline Bitboard ray_bb(Square s, SignedDirection d) {
- return RayBB[s][d];
+ return InFrontBB[c][rank_of(s)];
}
#if defined(IS_64BIT)
-inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) {
- Bitboard b = blockers & RMask[s];
- return RAttacks[RAttackIndex[s] + ((b * RMult[s]) >> RShift[s])];
+FORCE_INLINE unsigned rook_index(Square s, Bitboard occ) {
+ return unsigned(((occ & RMasks[s]) * RMagics[s]) >> RShifts[s]);
}
-inline Bitboard bishop_attacks_bb(Square s, Bitboard blockers) {
- Bitboard b = blockers & BMask[s];
- return BAttacks[BAttackIndex[s] + ((b * BMult[s]) >> BShift[s])];
+FORCE_INLINE unsigned bishop_index(Square s, Bitboard occ) {
+ return unsigned(((occ & BMasks[s]) * BMagics[s]) >> BShifts[s]);
}
#else // if !defined(IS_64BIT)
-inline Bitboard rook_attacks_bb(Square s, Bitboard blockers) {
- Bitboard b = blockers & RMask[s];
- return RAttacks[RAttackIndex[s] +
- (unsigned(int(b) * int(RMult[s]) ^
- int(b >> 32) * int(RMult[s] >> 32))
- >> RShift[s])];
+FORCE_INLINE unsigned rook_index(Square s, Bitboard occ) {
+ Bitboard b = occ & RMasks[s];
+ return unsigned(int(b) * int(RMagics[s]) ^ int(b >> 32) * int(RMagics[s] >> 32)) >> RShifts[s];
}
-inline Bitboard bishop_attacks_bb(Square s, Bitboard blockers) {
- Bitboard b = blockers & BMask[s];
- return BAttacks[BAttackIndex[s] +
- (unsigned(int(b) * int(BMult[s]) ^
- int(b >> 32) * int(BMult[s] >> 32))
- >> BShift[s])];
+FORCE_INLINE unsigned bishop_index(Square s, Bitboard occ) {
+ Bitboard b = occ & BMasks[s];
+ return unsigned(int(b) * int(BMagics[s]) ^ int(b >> 32) * int(BMagics[s] >> 32)) >> BShifts[s];
}
-
#endif
-inline Bitboard queen_attacks_bb(Square s, Bitboard blockers) {
- return rook_attacks_bb(s, blockers) | bishop_attacks_bb(s, blockers);
+inline Bitboard rook_attacks_bb(Square s, Bitboard occ) {
+ return RAttacks[s][rook_index(s, occ)];
+}
+
+inline Bitboard bishop_attacks_bb(Square s, Bitboard occ) {
+ return BAttacks[s][bishop_index(s, occ)];
}
/// 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. For instance,
-/// squares_in_front_of(BLACK, SQ_E4) returns a bitboard with the squares
-/// e3, e2 and e1 set.
+/// 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)
inline Bitboard squares_in_front_of(Color c, Square s) {
- return in_front_bb(c, s) & file_bb(s);
-}
-
-
-/// squares_behind is similar to squares_in_front, but returns the squares
-/// behind the square instead of in front of the square.
-
-inline Bitboard squares_behind(Color c, Square s) {
- return in_front_bb(opposite_color(c), s) & file_bb(s);
+ return SquaresInFrontMask[c][s];
}
/// 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.
+/// 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)
inline Bitboard passed_pawn_mask(Color c, Square s) {
return PassedPawnMask[c][s];
}
-/// outpost_mask takes a color and a square as input, and returns a bitboard
-/// mask which can be used to test whether a piece on the square can possibly
-/// be driven away by an enemy pawn.
+/// 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);
-inline Bitboard outpost_mask(Color c, Square s) {
- return OutpostMask[c][s];
+inline Bitboard attack_span_mask(Color c, Square s) {
+ return AttackSpanMask[c][s];
}
-/// isolated_pawn_mask takes a square as input, and returns a bitboard mask
-/// which can be used to test whether a pawn on the given square is isolated.
+/// squares_aligned returns true if the squares s1, s2 and s3 are aligned
+/// either on a straight or on a diagonal line.
-inline Bitboard isolated_pawn_mask(Square s) {
- return neighboring_files_bb(s);
+inline bool squares_aligned(Square s1, Square s2, Square s3) {
+ return (BetweenBB[s1][s2] | BetweenBB[s1][s3] | BetweenBB[s2][s3])
+ & ( SetMaskBB[s1] | SetMaskBB[s2] | SetMaskBB[s3]);
+}
+
+
+/// same_color_squares() returns a bitboard representing all squares with
+/// the same color of the given square.
+
+inline Bitboard same_color_squares(Square s) {
+ return bit_is_set(0xAA55AA55AA55AA55ULL, s) ? 0xAA55AA55AA55AA55ULL
+ : ~0xAA55AA55AA55AA55ULL;
}
/// pop_1st_bit() finds and clears the least significant nonzero bit in a
/// nonzero bitboard.
-#if defined(USE_BSFQ) // Assembly code by Heinz van Saanen
+#if defined(USE_BSFQ)
-inline Square __attribute__((always_inline)) first_1(Bitboard b) {
+#if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
+
+FORCE_INLINE Square first_1(Bitboard b) {
+ unsigned long index;
+ _BitScanForward64(&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);
+ return (Square) dummy;
}
+#endif
-inline Square __attribute__((always_inline)) pop_1st_bit(Bitboard* b) {
+FORCE_INLINE Square pop_1st_bit(Bitboard* b) {
const Square s = first_1(*b);
*b &= ~(1ULL<<s);
return s;
#endif
-////
-//// Prototypes
-////
-
extern void print_bitboard(Bitboard b);
-extern void init_bitboards();
-
+extern void bitboards_init();
#endif // !defined(BITBOARD_H_INCLUDED)
projects / stockfish / blobdiff