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) 2015-2018 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
}
+const Bitboard AllSquares = ~Bitboard(0);
const Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL;
const Bitboard FileABB = 0x0101010101010101ULL;
return b ^= SquareBB[s];
}
-inline bool more_than_one(Bitboard b) {
+constexpr bool more_than_one(Bitboard b) {
return b & (b - 1);
}
-
/// 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
-template<Square D>
-inline Bitboard shift(Bitboard b) {
+template<Direction D>
+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
}
+/// pawn_attacks_bb() returns the pawn attacks for the given color from the
+/// squares in the given bitboard.
+
+template<Color C>
+constexpr Bitboard pawn_attacks_bb(Bitboard b) {
+ return C == WHITE ? shift<NORTH_WEST>(b) | shift<NORTH_EAST>(b)
+ : shift<SOUTH_WEST>(b) | shift<SOUTH_EAST>(b);
+}
+
+
/// adjacent_files_bb() returns a bitboard representing all the squares on the
/// adjacent files of the given one.
}
-/// 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 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.
inline Bitboard forward_ranks_bb(Color c, Square s) {
return ForwardRanksBB[c][rank_of(s)];