Bitboard PassedPawnMask[2][64];
Bitboard AttackSpanMask[2][64];
-Bitboard BishopPseudoAttacks[64];
-Bitboard RookPseudoAttacks[64];
-Bitboard QueenPseudoAttacks[64];
+Bitboard PseudoAttacks[6][64];
uint8_t BitCount8Bit[256];
int SquareDistance[64][64];
for (Square s = SQ_A1; s <= SQ_H8; s++)
{
- BishopPseudoAttacks[s] = bishop_attacks_bb(s, 0);
- RookPseudoAttacks[s] = rook_attacks_bb(s, 0);
- QueenPseudoAttacks[s] = queen_attacks_bb(s, 0);
+ PseudoAttacks[BISHOP][s] = bishop_attacks_bb(s, 0);
+ PseudoAttacks[ROOK][s] = rook_attacks_bb(s, 0);
+ PseudoAttacks[QUEEN][s] = queen_attacks_bb(s, 0);
}
for (Square s1 = SQ_A1; s1 <= SQ_H8; s1++)
for (Square s2 = SQ_A1; s2 <= SQ_H8; s2++)
- if (bit_is_set(QueenPseudoAttacks[s1], s2))
+ if (bit_is_set(PseudoAttacks[QUEEN][s1], s2))
{
Square delta = (s2 - s1) / square_distance(s1, s2);
do
{
- if ( (Pt == QUEEN && !(QueenPseudoAttacks[from] & checkSqs))
- || (Pt == ROOK && !(RookPseudoAttacks[from] & checkSqs))
- || (Pt == BISHOP && !(BishopPseudoAttacks[from] & checkSqs)))
+ if ( (Pt == BISHOP || Pt == ROOK || Pt == QUEEN)
+ && !(PseudoAttacks[Pt][from] & checkSqs))
continue;
if (ci.dcCandidates && bit_is_set(ci.dcCandidates, from))
Bitboard b = pos.attacks_from(Piece(pt), from) & pos.empty_squares();
if (pt == KING)
- b &= ~QueenPseudoAttacks[ci.ksq];
+ b &= ~PseudoAttacks[QUEEN][ci.ksq];
SERIALIZE(b);
}
int checkersCnt = 0;
Color us = pos.side_to_move();
Square ksq = pos.king_square(us);
- Bitboard checkers = pos.checkers();
Bitboard sliderAttacks = 0;
+ Bitboard checkers = pos.checkers();
- assert(pos.piece_on(ksq) == make_piece(us, KING));
assert(checkers);
// Find squares attacked by slider checkers, we will remove them from the king
- // evasions set so to skip known illegal moves and avoid to do legality check later.
+ // evasions so to skip known illegal moves avoiding useless legality check later.
b = checkers;
do
{
switch (type_of(pos.piece_on(checksq)))
{
- case BISHOP: sliderAttacks |= BishopPseudoAttacks[checksq]; break;
- case ROOK: sliderAttacks |= RookPseudoAttacks[checksq]; break;
+ case BISHOP: sliderAttacks |= PseudoAttacks[BISHOP][checksq]; break;
+ case ROOK: sliderAttacks |= PseudoAttacks[ROOK][checksq]; break;
case QUEEN:
- // If queen and king are far we can safely remove all the squares attacked
- // in the other direction becuase are not reachable by the king anyway.
- if (squares_between(ksq, checksq) || (RookPseudoAttacks[checksq] & (1ULL << ksq)))
- sliderAttacks |= QueenPseudoAttacks[checksq];
-
- // Otherwise, if king and queen are adjacent and on a diagonal line, we need to
- // use real rook attacks to check if king is safe to move in the other direction.
- // For example: king in B2, queen in A1 a knight in B1, and we can safely move to C1.
+ // If queen and king are far or not on a diagonal line we can safely
+ // remove all the squares attacked in the other direction becuase are
+ // not reachable by the king anyway.
+ if (squares_between(ksq, checksq) || !bit_is_set(PseudoAttacks[BISHOP][checksq], ksq))
+ sliderAttacks |= PseudoAttacks[QUEEN][checksq];
+
+ // Otherwise we need to use real rook attacks to check if king is safe
+ // to move in the other direction. For example: king in B2, queen in A1
+ // a knight in B1, and we can safely move to C1.
else
- sliderAttacks |= BishopPseudoAttacks[checksq] | pos.attacks_from<ROOK>(checksq);
+ sliderAttacks |= PseudoAttacks[BISHOP][checksq] | pos.attacks_from<ROOK>(checksq);
default:
break;
if (checkersCnt > 1)
return mlist;
- // Target for blocking evasions or captures of the checking piece
+ // Blocking evasions or captures of the checking piece
target = squares_between(checksq, ksq) | checkers;
mlist = generate_piece_moves<PAWN, MV_EVASION>(pos, mlist, us, target);