}
-/// Position::pl_move_is_legal() tests whether a pseudo-legal move is legal.
-/// There are two versions of this function: One which takes only a
-/// move as input, and one which takes a move and a bitboard of pinned
-/// pieces. The latter function is faster, and should always be preferred
-/// when a pinned piece bitboard has already been computed.
+/// Position::pl_move_is_legal() tests whether a pseudo-legal move is legal
-bool Position::pl_move_is_legal(Move m) const {
-
- return pl_move_is_legal(m, pinned_pieces(side_to_move()));
-}
-
-bool Position::pl_move_is_legal(Move m, Bitboard pinned) const {
+bool Position::pl_move_is_legal(Move m) const {
assert(is_ok());
assert(move_is_ok(m));
- assert(pinned == pinned_pieces(side_to_move()));
// If we're in check, all pseudo-legal moves are legal, because our
// check evasion generator only generates true legal moves.
// A non-king move is legal if and only if it is not pinned or it
// is moving along the ray towards or away from the king.
- return ( !bit_is_set(pinned, from)
+ return ( !bit_is_set(pinned_pieces(us), from)
|| (direction_between_squares(from, ksq) == direction_between_squares(move_to(m), ksq)));
}
-/// Position::move_is_check() tests whether a pseudo-legal move is a check.
-/// There are two versions of this function: One which takes only a move as
-/// input, and one which takes a move and a bitboard of discovered check
-/// candidates. The latter function is faster, and should always be preferred
-/// when a discovered check candidates bitboard has already been computed.
+/// Position::move_is_check() tests whether a pseudo-legal move is a check
bool Position::move_is_check(Move m) const {
- Bitboard dc = discovered_check_candidates(side_to_move());
- return move_is_check(m, dc);
-}
-
-bool Position::move_is_check(Move m, Bitboard dcCandidates) const {
-
assert(is_ok());
assert(move_is_ok(m));
- assert(dcCandidates == discovered_check_candidates(side_to_move()));
Color us = side_to_move();
Color them = opposite_color(us);
Square from = move_from(m);
Square to = move_to(m);
Square ksq = king_square(them);
+ Bitboard dcCandidates = discovered_check_candidates(us);
assert(color_of_piece_on(from) == us);
assert(piece_on(ksq) == piece_of_color_and_type(them, KING));
void Position::backup(UndoInfo& u) const {
- u.castleRights = castleRights;
- u.epSquare = epSquare;
+ for (Color c = WHITE; c <= BLACK; c++)
+ {
+ u.pinners[c] = pinners[c];
+ u.pinned[c] = pinned[c];
+ u.dcCandidates[c] = dcCandidates[c];
+ }
u.checkersBB = checkersBB;
u.key = key;
u.pawnKey = pawnKey;
u.materialKey = materialKey;
+ u.castleRights = castleRights;
u.rule50 = rule50;
+ u.epSquare = epSquare;
u.lastMove = lastMove;
u.mgValue = mgValue;
u.egValue = egValue;
u.capture = NO_PIECE_TYPE;
-
- for (Color c = WHITE; c <= BLACK; c++)
- {
- u.pinners[c] = pinners[c];
- u.pinned[c] = pinned[c];
- u.dcCandidates[c] = dcCandidates[c];
- }
}
void Position::restore(const UndoInfo& u) {
- castleRights = u.castleRights;
- epSquare = u.epSquare;
+ for (Color c = WHITE; c <= BLACK; c++)
+ {
+ pinners[c] = u.pinners[c];
+ pinned[c] = u.pinned[c];
+ dcCandidates[c] = u.dcCandidates[c];
+ }
checkersBB = u.checkersBB;
key = u.key;
pawnKey = u.pawnKey;
materialKey = u.materialKey;
+ castleRights = u.castleRights;
rule50 = u.rule50;
+ epSquare = u.epSquare;
lastMove = u.lastMove;
mgValue = u.mgValue;
egValue = u.egValue;
// u.capture is restored in undo_move()
-
- for (Color c = WHITE; c <= BLACK; c++)
- {
- pinners[c] = u.pinners[c];
- pinned[c] = u.pinned[c];
- dcCandidates[c] = u.dcCandidates[c];
- }
}
/// Position::do_move() makes a move, and backs up all information necessary
/// to undo the move to an UndoInfo object. The move is assumed to be legal.
/// Pseudo-legal moves should be filtered out before this function is called.
-/// There are two versions of this function, one which takes only the move and
-/// the UndoInfo as input, and one which takes a third parameter, a bitboard of
-/// discovered check candidates. The second version is faster, because knowing
-/// the discovered check candidates makes it easier to update the checkersBB
-/// member variable in the position object.
void Position::do_move(Move m, UndoInfo& u) {
- do_move(m, u, discovered_check_candidates(side_to_move()));
-}
-
-void Position::do_move(Move m, UndoInfo& u, Bitboard dc) {
-
assert(is_ok());
assert(move_is_ok(m));
+ // Get now the current (pre-move) dc candidates that we will use
+ // in update_checkers().
+ Bitboard oldDcCandidates = discovered_check_candidates(side_to_move());
+
// Back up the necessary information to our UndoInfo object (except the
// captured piece, which is taken care of later.
backup(u);
Square ksq = king_square(them);
switch (piece)
{
- case PAWN: update_checkers<PAWN>(&checkersBB, ksq, from, to, dc); break;
- case KNIGHT: update_checkers<KNIGHT>(&checkersBB, ksq, from, to, dc); break;
- case BISHOP: update_checkers<BISHOP>(&checkersBB, ksq, from, to, dc); break;
- case ROOK: update_checkers<ROOK>(&checkersBB, ksq, from, to, dc); break;
- case QUEEN: update_checkers<QUEEN>(&checkersBB, ksq, from, to, dc); break;
- case KING: update_checkers<KING>(&checkersBB, ksq, from, to, dc); break;
+ case PAWN: update_checkers<PAWN>(&checkersBB, ksq, from, to, oldDcCandidates); break;
+ case KNIGHT: update_checkers<KNIGHT>(&checkersBB, ksq, from, to, oldDcCandidates); break;
+ case BISHOP: update_checkers<BISHOP>(&checkersBB, ksq, from, to, oldDcCandidates); break;
+ case ROOK: update_checkers<ROOK>(&checkersBB, ksq, from, to, oldDcCandidates); break;
+ case QUEEN: update_checkers<QUEEN>(&checkersBB, ksq, from, to, oldDcCandidates); break;
+ case KING: update_checkers<KING>(&checkersBB, ksq, from, to, oldDcCandidates); break;
default: assert(false); break;
}
}
projects / stockfish / blobdiff