constexpr Bitboard Rank7BB = Rank1BB << (8 * 6);
constexpr Bitboard Rank8BB = Rank1BB << (8 * 7);
-extern int8_t 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 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 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
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);
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.
}
-/// shift() moves a bitboard one step along direction D (mainly for pawns)
+/// shift() moves a bitboard one step along direction D
template<Direction D>
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<Color C>
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<Color C>
-constexpr Bitboard double_pawn_attacks_bb(Bitboard b) {
+constexpr Bitboard pawn_double_attacks_bb(Bitboard b) {
return C == WHITE ? shift<NORTH_WEST>(b) & shift<NORTH_EAST>(b)
: shift<SOUTH_WEST>(b) & shift<SOUTH_EAST>(b);
}
return shift<EAST>(file_bb(f)) | shift<WEST>(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 ForwardRanksBB[c][rank_of(s)] & file_bb(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:
+/// 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 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:
+/// 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 pawn_attack_span(c, s) | forward_file_bb(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));
}
/// 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<typename T> inline int distance(T x, T y) { return x < y ? y - x : x - y; }
+template<typename T> inline int distance(T x, T y) { return std::abs(x - y); }
template<> inline int distance<Square>(Square x, Square y) { return SquareDistance[x][y]; }
template<typename T1, typename T2> inline int distance(T2 x, T2 y);
template<> inline int distance<File>(Square x, Square y) { return distance(file_of(x), file_of(y)); }
template<> inline int distance<Rank>(Square x, Square y) { return distance(rank_of(x), rank_of(y)); }
+template<class T> 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'.
#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]];
projects / stockfish / blobdiff