/// Position::pl_move_is_legal() tests whether a pseudo-legal move is legal
-bool Position::pl_move_is_legal(Move m) const {
-
- // If we're in check, all pseudo-legal moves are legal, because our
- // check evasion generator only generates true legal moves.
- return is_check() || pl_move_is_legal(m, pinned_pieces(side_to_move()));
-}
-
bool Position::pl_move_is_legal(Move m, Bitboard pinned) const {
assert(is_ok());
assert(move_is_ok(m));
assert(pinned == pinned_pieces(side_to_move()));
- assert(!is_check());
// Castling moves are checked for legality during move generation.
if (move_is_castle(m))
assert(color_of_piece_on(from) == us);
assert(piece_on(king_square(us)) == piece_of_color_and_type(us, KING));
- // En passant captures are a tricky special case. Because they are
+ // En passant captures are a tricky special case. Because they are
// rather uncommon, we do it simply by testing whether the king is attacked
// after the move is made
if (move_is_ep(m))
}
+/// Position::pl_move_is_evasion() tests whether a pseudo-legal move is a legal evasion
+
+bool Position::pl_move_is_evasion(Move m, Bitboard pinned) const
+{
+ assert(pos.is_check());
+
+ Color us = side_to_move();
+ Square from = move_from(m);
+ Square to = move_to(m);
+
+ // King moves and en-passant captures are verified in pl_move_is_legal()
+ if (type_of_piece_on(from) == KING || move_is_ep(m))
+ return pl_move_is_legal(m, pinned);
+
+ Bitboard target = checkers();
+ Square checksq = pop_1st_bit(&target);
+
+ if (target) // double check ?
+ return false;
+
+ // Our move must be a blocking evasion or a capture of the checking piece
+ target = squares_between(checksq, king_square(us)) | checkers();
+ return bit_is_set(target, to) && pl_move_is_legal(m, pinned);
+}
+
+
/// Position::move_is_check() tests whether a pseudo-legal move is a check
bool Position::move_is_check(Move m) const {
Bitboard attackers, stmAttackers, b;
- assert(!shortcut || from != SQ_NONE);
assert(square_is_ok(from) || from == SQ_NONE);
assert(square_is_ok(to));
bool Position::is_mate() const {
MoveStack moves[256];
-
- return is_check() && (generate_evasions(*this, moves, pinned_pieces(sideToMove)) == moves);
+ return is_check() && (generate_moves(*this, moves, false) == moves);
}
MoveStack mlist[120];
bool result = false;
- Bitboard dc = discovered_check_candidates(sideToMove);
Bitboard pinned = pinned_pieces(sideToMove);
// Generate pseudo-legal non-capture and capture check moves
- MoveStack* last = generate_non_capture_checks(*this, mlist, dc);
+ MoveStack* last = generate_non_capture_checks(*this, mlist);
last = generate_captures(*this, last);
// Loop through the moves, and see if one of them is mate