In current master, the function make_bitboard() does nothing apart from
helping initialize the SquareBB[] array. This seems like an unnecessary
abstraction layer.
The advantage of make_bitboard() is we can define a bitboard, in a simple
and general way, not only from a single square but also from a list of
squares. It is more elegant, faster and readable than combining multiple
SquareBB explicitly, but the last complex use case in evaluation was
simplified away a few months ago.
If make_bitboard() becomes useful again to define complicated bitboards,
it will be easy enough to reintroduce it using this pull request as
an implementation reference.
No functional change.
PopCnt16[i] = (uint8_t) popcount16(i);
for (Square s = SQ_A1; s <= SQ_H8; ++s)
- SquareBB[s] = make_bitboard(s);
+ SquareBB[s] = (1ULL << s);
for (File f = FILE_A; f <= FILE_H; ++f)
FileBB[f] = f > FILE_A ? FileBB[f - 1] << 1 : FileABB;
}
-/// make_bitboard() returns a bitboard from a list of squares
-
-constexpr Bitboard make_bitboard() { return 0; }
-
-template<typename ...Squares>
-constexpr Bitboard make_bitboard(Square s, Squares... squares) {
- return (1ULL << s) | make_bitboard(squares...);
-}
-
-
/// shift() moves a bitboard one step along direction D (mainly for pawns)
template<Direction D>