/*
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) 2008-2012 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 "piece.h"
-#include "square.h"
#include "types.h"
-
-////
-//// Constants and variables
-////
-
-const Bitboard EmptyBoardBB = 0;
-
-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 const Bitboard SquaresByColorBB[2];
-extern const Bitboard FileBB[8];
-extern const Bitboard NeighboringFilesBB[8];
-extern const Bitboard ThisAndNeighboringFilesBB[8];
-extern const Bitboard RankBB[8];
-extern const Bitboard RelativeRankBB[2][8];
-extern const Bitboard InFrontBB[2][8];
-
-extern Bitboard SetMaskBB[65];
-extern Bitboard ClearMaskBB[65];
-
-extern Bitboard StepAttackBB[16][64];
+CACHE_LINE_ALIGNMENT
+
+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];
-extern const uint64_t RMult[64];
-extern const int RShift[64];
-extern Bitboard RMask[64];
-extern int RAttackIndex[64];
-extern Bitboard RAttacks[0x19000];
-
-extern const uint64_t BMult[64];
-extern const int BShift[64];
-extern Bitboard BMask[64];
-extern int BAttackIndex[64];
-extern Bitboard BAttacks[0x1480];
-
-extern Bitboard BishopPseudoAttacks[64];
-extern Bitboard RookPseudoAttacks[64];
-extern Bitboard QueenPseudoAttacks[64];
-extern uint8_t BitCount8Bit[256];
+/// 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 functions
-////
-
-/// Functions for testing whether a given bit is set in a bitboard, and for
-/// setting and clearing bits.
-
-inline Bitboard bit_is_set(Bitboard b, Square s) {
- return b & SetMaskBB[s];
+inline Bitboard operator&(Bitboard b, Square s) {
+ return b & SquareBB[s];
}
-inline void set_bit(Bitboard *b, Square s) {
- *b |= SetMaskBB[s];
+inline Bitboard& operator|=(Bitboard& b, Square s) {
+ return b |= SquareBB[s], b;
}
-inline void clear_bit(Bitboard *b, Square s) {
- *b &= ClearMaskBB[s];
-}
-
-
-/// Functions used to update a bitboard after a move. This is faster
-/// then calling a sequence of clear_bit() + set_bit()
-
-inline Bitboard make_move_bb(Square from, Square to) {
- return SetMaskBB[from] | SetMaskBB[to];
+inline Bitboard& operator^=(Bitboard& b, Square s) {
+ return b ^= SquareBB[s], b;
}
-inline void do_move_bb(Bitboard *b, Bitboard move_bb) {
- *b ^= move_bb;
-}
-/// rank_bb() and file_bb() take a file or a square as input, and return
+/// 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) {
}
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];
+ return FileBB[file_of(s)];
}
-inline Bitboard neighboring_files_bb(Square s) {
- return NeighboringFilesBB[square_file(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.
-inline Bitboard this_and_neighboring_files_bb(File f) {
- return ThisAndNeighboringFilesBB[f];
-}
+/// 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(Square s) {
- return ThisAndNeighboringFilesBB[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 InFrontBB[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 InFrontBB[opposite_color(c)][square_rank(s)];
+ 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 r_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 b_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 r_index(Square s, Bitboard occ) {
+ unsigned lo = unsigned(occ) & unsigned(RMasks[s]);
+ unsigned hi = unsigned(occ >> 32) & unsigned(RMasks[s] >> 32);
+ return (lo * unsigned(RMagics[s]) ^ hi * unsigned(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 b_index(Square s, Bitboard occ) {
+ unsigned lo = unsigned(occ) & unsigned(BMasks[s]);
+ unsigned hi = unsigned(occ >> 32) & unsigned(BMasks[s] >> 32);
+ return (lo * unsigned(BMagics[s]) ^ hi * unsigned(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][r_index(s, occ)];
+}
+
+inline Bitboard bishop_attacks_bb(Square s, Bitboard occ) {
+ return BAttacks[s][b_index(s, occ)];
}
}
-/// 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 SquaresInFrontMask[opposite_color(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. Definition of the table is:
-/// PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_neighboring_files_bb(s)
+/// 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];
/// 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) & neighboring_files_bb(s);
+/// AttackSpanMask[c][s] = in_front_bb(c, s) & adjacent_files_bb(s);
inline Bitboard attack_span_mask(Color c, Square s) {
return AttackSpanMask[c][s];
}
+/// squares_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]);
+}
+
+
+/// 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 Bitboard(0xAA55AA55AA55AA55ULL) & s ? 0xAA55AA55AA55AA55ULL
+ : ~0xAA55AA55AA55AA55ULL;
+}
+
+
/// 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.
-#if defined(USE_BSFQ) // Assembly code by Heinz van Saanen
+#if defined(USE_BSFQ)
-inline Square 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 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