static bool add_pawn_moves(list_t * list, const board_t * board, int to, bool legal, bool stop) { int me; int inc; int pawn; int from; int piece; ASSERT(list!=NULL); ASSERT(board!=NULL); ASSERT(SQUARE_IS_OK(to)); ASSERT(legal==true||legal==false); ASSERT(stop==true||stop==false); ASSERT(board->square[to]==Empty); me = board->turn; inc = PAWN_MOVE_INC(me); pawn = PAWN_MAKE(me); from = to - inc; piece = board->square[from]; if (piece == pawn) { // single push if (!legal || !is_pinned(board,from,me)) { if (stop) return true; add_pawn_move(list,from,to); } } else if (piece == Empty && PAWN_RANK(to,me) == Rank4) { // double push from = to - (2*inc); if (board->square[from] == pawn) { if (!legal || !is_pinned(board,from,me)) { if (stop) return true; ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE(from,to)); } } } return false; }
static void add_captures(list_t * list, const board_t * board) { int me, opp; int opp_flag; const sq_t * ptr; int from, to; int piece, capture; ASSERT(list!=NULL); ASSERT(board!=NULL); me = board->turn; opp = COLOUR_OPP(me); opp_flag = COLOUR_FLAG(opp); // piece captures for (ptr = &board->piece[me][0]; (from=*ptr) != SquareNone; ptr++) { piece = board->square[from]; switch (PIECE_TYPE(piece)) { case Knight64: to = from - 33; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from - 31; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from - 18; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from - 14; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from + 14; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from + 18; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from + 31; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from + 33; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); break; case Bishop64: for (to = from-17; (capture=board->square[to]) == Empty; to -= 17) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from-15; (capture=board->square[to]) == Empty; to -= 15) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from+15; (capture=board->square[to]) == Empty; to += 15) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from+17; (capture=board->square[to]) == Empty; to += 17) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); break; case Rook64: for (to = from-16; (capture=board->square[to]) == Empty; to -= 16) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from-1; (capture=board->square[to]) == Empty; to -= 1) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from+1; (capture=board->square[to]) == Empty; to += 1) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from+16; (capture=board->square[to]) == Empty; to += 16) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); break; case Queen64: for (to = from-17; (capture=board->square[to]) == Empty; to -= 17) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from-16; (capture=board->square[to]) == Empty; to -= 16) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from-15; (capture=board->square[to]) == Empty; to -= 15) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from-1; (capture=board->square[to]) == Empty; to -= 1) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from+1; (capture=board->square[to]) == Empty; to += 1) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from+15; (capture=board->square[to]) == Empty; to += 15) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from+16; (capture=board->square[to]) == Empty; to += 16) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); for (to = from+17; (capture=board->square[to]) == Empty; to += 17) ; if (FLAG_IS(capture,opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); break; case King64: to = from - 17; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from - 16; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from - 15; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from - 1; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from + 1; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from + 15; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from + 16; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); to = from + 17; if (FLAG_IS(board->square[to],opp_flag)) LIST_ADD(list,MOVE_MAKE(from,to)); break; default: ASSERT(false); break; } } // pawn captures if (COLOUR_IS_WHITE(me)) { for (ptr = &board->pawn[me][0]; (from=*ptr) != SquareNone; ptr++) { to = from + 15; if (FLAG_IS(board->square[to],opp_flag)) add_pawn_move(list,from,to); to = from + 17; if (FLAG_IS(board->square[to],opp_flag)) add_pawn_move(list,from,to); // promote if (SQUARE_RANK(from) == Rank7) { to = from + 16; if (board->square[to] == Empty) { add_promote(list,MOVE_MAKE(from,to)); } } } } else { // black for (ptr = &board->pawn[me][0]; (from=*ptr) != SquareNone; ptr++) { to = from - 17; if (FLAG_IS(board->square[to],opp_flag)) add_pawn_move(list,from,to); to = from - 15; if (FLAG_IS(board->square[to],opp_flag)) add_pawn_move(list,from,to); // promote if (SQUARE_RANK(from) == Rank2) { to = from - 16; if (board->square[to] == Empty) { add_promote(list,MOVE_MAKE(from,to)); } } } } }
static void add_moves(list_t * list, const board_t * board) { int me, opp; int opp_flag; const sq_t * ptr; int from, to; int piece, capture; const inc_t * inc_ptr; int inc; ASSERT(list!=NULL); ASSERT(board!=NULL); me = board->turn; opp = COLOUR_OPP(me); opp_flag = COLOUR_FLAG(opp); // piece moves for (ptr = &board->piece[me][0]; (from=*ptr) != SquareNone; ptr++) { piece = board->square[from]; inc_ptr = PIECE_INC(piece); if (PIECE_IS_SLIDER(piece)) { for (; (inc=*inc_ptr) != IncNone; inc_ptr++) { for (to = from+inc; (capture=board->square[to]) == Empty; to += inc) { LIST_ADD(list,MOVE_MAKE(from,to)); } if (FLAG_IS(capture,opp_flag)) { LIST_ADD(list,MOVE_MAKE(from,to)); } } } else { for (; (inc=*inc_ptr) != IncNone; inc_ptr++) { to = from + inc; capture = board->square[to]; if (capture == Empty || FLAG_IS(capture,opp_flag)) { LIST_ADD(list,MOVE_MAKE(from,to)); } } } } // pawn moves inc = PAWN_MOVE_INC(me); for (ptr = &board->pawn[me][0]; (from=*ptr) != SquareNone; ptr++) { to = from + (inc-1); if (FLAG_IS(board->square[to],opp_flag)) { add_pawn_move(list,from,to); } to = from + (inc+1); if (FLAG_IS(board->square[to],opp_flag)) { add_pawn_move(list,from,to); } to = from + inc; if (board->square[to] == Empty) { add_pawn_move(list,from,to); if (PAWN_RANK(from,me) == Rank2) { to = from + (2*inc); if (board->square[to] == Empty) { ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE(from,to)); } } } } }
static bool add_pawn_captures(list_t * list, const board_t * board, int to, bool legal, bool stop) { int me; int inc; int pawn; int from; ASSERT(list!=NULL); ASSERT(board!=NULL); ASSERT(SQUARE_IS_OK(to)); ASSERT(legal==true||legal==false); ASSERT(stop==true||stop==false); ASSERT(COLOUR_IS(board->square[to],COLOUR_OPP(board->turn))); me = board->turn; inc = PAWN_MOVE_INC(me); pawn = PAWN_MAKE(me); from = to - (inc-1); if (board->square[from] == pawn) { if (!legal || !is_pinned(board,from,me)) { if (stop) return true; add_pawn_move(list,from,to); } } from = to - (inc+1); if (board->square[from] == pawn) { if (!legal || !is_pinned(board,from,me)) { if (stop) return true; add_pawn_move(list,from,to); } } if (board->ep_square != SquareNone && to == SQUARE_EP_DUAL(board->ep_square)) { ASSERT(PAWN_RANK(to,me)==Rank5); ASSERT(PIECE_IS_PAWN(board->square[to])); to = board->ep_square; ASSERT(PAWN_RANK(to,me)==Rank6); ASSERT(board->square[to]==Empty); from = to - (inc-1); if (board->square[from] == pawn) { if (!legal || !is_pinned(board,from,me)) { if (stop) return true; ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE_FLAGS(from,to,MoveEnPassant)); } } from = to - (inc+1); if (board->square[from] == pawn) { if (!legal || !is_pinned(board,from,me)) { if (stop) return true; ASSERT(!SQUARE_IS_PROMOTE(to)); LIST_ADD(list,MOVE_MAKE_FLAGS(from,to,MoveEnPassant)); } } } return false; }
// Non-capturing checks. //------------------------------------------------------------------------------ MoveGen *generate_checks(MoveGen *self) { Position *p = self->p; int color = p->color, enemy = p->color ^ 1; int square = (int)p->king[enemy]; // Non-capturing Knight checks. Bitmask prohibit = maskNone; Bitmask checks = knightMoves[square]; Bitmask outposts = p->outposts[knight(color)]; while (any(outposts)) { int from = pop(&outposts); add_piece_move(self, from, knightMoves[from] & checks & ~p->board); } // Non-capturing Bishop or Queen checks. checks = targets_for(p, square, bishop(enemy)); outposts = p->outposts[bishop(color)] | p->outposts[queen(color)]; while (any(outposts)) { int from = pop(&outposts); Bitmask squares = targets_for(p, from, bishop(enemy)) & checks & ~p->outposts[enemy]; while (any(squares)) { int to = pop(&squares); Piece piece = p->pieces[to]; if (!piece) { // Empty square: simply move a bishop to check. append(self, new_move(p, from, to)); } else if (color(piece) == color && any(maskDiagonal[from][square])) { // Non-empty square occupied by friendly piece on the same // diagonal: moving the piece away causes discovered check. switch (kind(piece)) { case Pawn: // Block pawn promotions (since they are treated as // captures) and en-passant captures. prohibit = maskRank[0] | maskRank[7]; if (p->enpassant) { prohibit |= bit[p->enpassant]; } add_pawn_move(self, to, targets(p, to) & ~p->board & ~prohibit); break; case King: // Make sure the king steps out of attack diaginal. add_king_move(self, to, targets(p, to) & ~p->board & ~maskBlock[from][square]); break; default: add_piece_move(self, to, targets(p, to) & ~p->board); } } } if (is_queen(p->pieces[from])) { // Queen could move straight as a rook and check diagonally as a bishop // or move diagonally as a bishop and check straight as a rook. Bitmask squares = (targets_for(p, from, rook(color)) & checks) | (targets_for(p, from, bishop(color)) & targets_for(p, square, rook(color))); add_piece_move(self, from, squares & ~p->board); } } // Non-capturing Rook or Queen checks. checks = targets_for(p, square, rook(enemy)); outposts = p->outposts[rook(color)] | p->outposts[queen(color)]; while (any(outposts)) { int from = pop(&outposts); Bitmask squares = targets_for(p, from, rook(enemy)) & checks & ~p->outposts[enemy]; while (any(squares)) { int to = pop(&squares); Piece piece = p->pieces[to]; if (!piece) { // Empty square: simply move a rook to check. append(self, new_move(p, from, to)); } else if (color(piece) == color) { if (any(maskStraight[from][square])) { // Non-empty square occupied by friendly piece on the same // file or rank: moving the piece away causes discovered check. switch (kind(piece)) { case Pawn: // If pawn and rook share the same file then non-capturing // discovered check is not possible since the pawn is going // to stay on the same file no matter what. if (col(from) == col(to)) { continue; } // Block pawn promotions (since they are treated as captures) // and en-passant captures. prohibit = maskRank[0] | maskRank[7]; if (p->enpassant) { prohibit |= bit[p->enpassant]; } add_pawn_move(self, to, targets(p, to) & ~p->board & ~prohibit); break; case King: // Make sure the king steps out of attack file or rank. prohibit = maskNone; if (row(from) == row(square)) { prohibit = maskRank[row(from)]; } else { prohibit = maskFile[col(square)]; } add_king_move(self, to, targets(p, to) & ~p->board & ~prohibit); break; default: add_piece_move(self, to, targets(p, to) & ~p->board); } } } } } // Non-capturing Pawn checks. outposts = p->outposts[pawn(color)] & maskIsolated[col(square)]; while (any(outposts)) { int from = pop(&outposts); Bitmask target = maskPawn[color][square] & targets(p, from); if (any(target)) { append(self, new_pawn_move(p, from, pop(&target))); } } return self; }