unsigned long long calculate_zobrist(struct Board * board)
{
unsigned long long zobristHash = 0;
int i;
for(i = 0; i < 12; ++i)
{
bitboard piece = board->pieces[i];
while (piece)
{
int index = bit_scan_forward(piece);
zobristHash ^= pieceKeys[i][index];
piece = clear_lsb(piece);
}
}
if (board->sideToMove == BLACK)
{
zobristHash ^= blackToMoveKey;
}
assert(board->castling < 16);
zobristHash ^= castlingKeys[board->castling];
if (board->enPassant)
{
int index = bit_scan_forward(board->enPassant);
zobristHash ^= enPassantKeys[index];
}
return zobristHash;
}
void MoveGenerator::add_moves(U8 from, U64 targets, class MoveList& list, const class Board &board, const U32 flags){
while(targets){
U32 to = bit_scan_forward(targets);
U32 capture = board[to];
U32 move = from | (to << 8) | (capture << 24) | flags;
list.push(move);
targets &= targets - 1;
}
}
void MoveGenerator::add_king_moves(class MoveList &list, const class Board &board, const int side){
U64 kings = board.bitboards[KING|side];
U64 non_friendly = ~board.bitboards[side];
while(kings){
U8 from = bit_scan_forward(kings);
U64 targets = KING_LOOKUP_TABLE[from] & non_friendly;
add_moves(from, targets, list, board, NO_FLAGS);
kings &= kings - 1;
}
}
void MoveGenerator::add_moves_with_diff(int diff, U64 targets, class MoveList& list, const class Board &board, const U32 flags){
while(targets){
U32 to = bit_scan_forward(targets);
U32 from = ((U32)(to - diff)) % 64;
U32 capture = board[to];
U32 move = from | (to << 8) | flags | (capture << 24);
list.push(move);
targets &= targets - 1;
}
}
U64
get_positive_ray_attacks(U64 occupied, enum Direction dir, U64 square)
{
U64 attacks = ray_attacks[dir][square];
U64 blocker = attacks & occupied;
if ( blocker ) {
square = bit_scan_forward(blocker);
attacks ^= ray_attacks[dir][square];
}
return attacks;
}
unsigned int perft_perft(Board* board, unsigned int depth)
{
int i, nperft = 0;
Move moves[256];
if (depth == 0)
{
return 1;
}
TTEntry* ttentry = get_tt_entry_at_depth(board->zobrist, depth);
if (ttentry)
{
return ttentry->score;
}
unsigned int numMoves = generate_moves(board, moves);
for (i = 0; i < numMoves; ++i)
{
make_move(board, moves[i]);
if ((board->sideToMove == BLACK &&
!black_attacks_square(board, bit_scan_forward(board->pieces[WHITE_KING]))) ||
(board->sideToMove == WHITE &&
!white_attacks_square(board, bit_scan_forward(board->pieces[BLACK_KING]))))
{
nperft += perft_perft(board, depth - 1);
}
unmake_move(board, moves[i]);
}
TTEntry new_entry;
new_entry.key = board->zobrist;
new_entry.score = nperft;
new_entry.depth = depth;
put_tt_entry(&new_entry);
return nperft;
}
void MoveGenerator::add_promotions_with_diff(int diff, U64 targets, class MoveList& list, const class Board &board, const U32 side){
U32 flags = side << 16; // move to third byte
while(targets){
U32 to = bit_scan_forward(targets);
U32 from = ((U32)(to - diff)) % 64;
U32 capture = board[to];
U32 move = from | (to << 8) | flags | (capture << 24) ;
list.push(move | (KNIGHT << 16));
list.push(move | (BISHOP << 16));
list.push(move | (ROOK << 16));
list.push(move | (QUEEN << 16));
targets &= targets - 1;
}
}
int evaluate_piece(bitboard pieces, int* squareValues, int pieceValue)
{
int score = 0;
while(pieces)
{
int pieceSquare = bit_scan_forward(pieces);
score += squareValues[pieceSquare] + pieceValue;
pieces = clear_lsb(pieces);
}
return score;
}
inline static int fm_bmp_first_set(struct fm_block* qm, int start)
{
int bmp_idx;
int bit;
int r;
fm_hash_bitmap_t test_val;
fm_hash_bitmap_t v;
bmp_idx=start/FM_HASH_BMP_BITS;
bit=start%FM_HASH_BMP_BITS;
test_val=1UL <<((unsigned long)bit);
if (qm->free_bitmap[bmp_idx] & test_val)
return start;
else if (qm->free_bitmap[bmp_idx] & ~(test_val-1)){
#if 0
test_val<<=1;
for (r=bit+1; r<FM_HASH_BMP_BITS; r++, test_val<<=1){
if (qm->free_bitmap[bmp_idx] & test_val)
return (start-bit+r);
}
#endif
v=qm->free_bitmap[bmp_idx]>>(bit+1);
return start+1+bit_scan_forward((unsigned long)v);
}
int
movegen(struct Game* game, int move_count)
{
U64 temp_move, temp_move2, temp_piece;
U32 from, to, move;
U64 free_squares = game->board[OCCUPIED][0];
if (game->to_move == WHITE)
{
/***************/
/* WHITE PAWNS */
/***************/
temp_move = step_up(game->board[PAWNS][WHITE]) & free_squares;
temp_move2 = temp_move;
/* single pushes */
while (temp_move)
{
to = bit_scan_forward(temp_move);
if (to/8 == 7)
{ /* time for a promotion */
game->move_buffer[move_count++] = create_move(to-8,to,BISHOP_PROMO_FLAG);
game->move_buffer[move_count++] = create_move(to-8,to,KNIGHT_PROMO_FLAG);
game->move_buffer[move_count++] = create_move(to-8,to,ROOK_PROMO_FLAG);
game->move_buffer[move_count++] = create_move(to-8,to,QUEEN_PROMO_FLAG);
} else game->move_buffer[move_count++] = create_move(to-8,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* double pushes */
temp_move2 = step_up(temp_move2) & free_squares & rank4;
while (temp_move2)
{
to = bit_scan_forward(temp_move2);
game->move_buffer[move_count++] = create_move(to-16,to,DOUBLE_PAWN_PUSH_FLAG);
temp_move2 &= temp_move2 - 1;
}
/* captures */
/* TODO: add en passante capture */
temp_piece = game->board[PAWNS][WHITE];
while (temp_piece)
{
from = bit_scan_forward(temp_piece);
temp_move = pawn_attacks[WHITE][from] & game->board[PIECES][BLACK];
while (temp_move)
{
to = bit_scan_forward(temp_move);
if (to/8 == 7)
{ /* time for a promotion */
game->move_buffer[move_count++] = create_move(from,to,BISHOP_PROMO_CAPTURE_FLAG);
game->move_buffer[move_count++] = create_move(from,to,KNIGHT_PROMO_CAPTURE_FLAG);
game->move_buffer[move_count++] = create_move(from,to,ROOK_PROMO_CAPTURE_FLAG);
game->move_buffer[move_count++] = create_move(from,to,QUEEN_PROMO_CAPTURE_FLAG);
} else game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
temp_piece &= temp_piece - 1;
}
/*****************/
/* WHITE KNIGHTS */
/*****************/
temp_piece = game->board[KNIGHTS][WHITE];
while (temp_piece)
{
from = bit_scan_forward(temp_piece);
/* quiets */
temp_move = knight_table[from] & free_squares;
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* captures */
temp_move = knight_table[from] & game->board[PIECES][BLACK];
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
temp_piece &= temp_piece - 1;
}
/*****************/
/* WHITE BISHOPS */
/*****************/
temp_piece = game->board[BISHOPS][WHITE];
while (temp_piece)
{
from = bit_scan_forward(temp_piece);
temp_move2 = get_bishop_attacks(game->board[OCCUPIED][1], from);
/* quiets */
temp_move = temp_move2 & free_squares;
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* captures */
temp_move = temp_move2 & game->board[PIECES][BLACK];
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
temp_piece &= temp_piece - 1;
}
/***************/
/* WHITE ROOKS */
/***************/
temp_piece = game->board[ROOKS][WHITE];
while (temp_piece)
{
from = bit_scan_forward(temp_piece);
temp_move2 = get_rook_attacks(game->board[OCCUPIED][1], from);
/* quiets */
temp_move = temp_move2 & free_squares;
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* captures */
temp_move = temp_move2 & game->board[PIECES][BLACK];
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
temp_piece &= temp_piece - 1;
}
/****************/
/* WHITE QUEENS */
/****************/
temp_piece = game->board[QUEENS][WHITE];
while (temp_piece)
{
from = bit_scan_forward(temp_piece);
temp_move2 = get_queen_attacks(game->board[OCCUPIED][1], from);
/* quiets */
temp_move = temp_move2 & free_squares;
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* captures */
temp_move = temp_move2 & game->board[PIECES][BLACK];
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
temp_piece &= temp_piece - 1;
}
/**************/
/* WHITE KINGS */
/**************/
temp_piece = game->board[KINGS][WHITE];
from = bit_scan_forward(temp_piece);
/* quiets */
temp_move = king_table[from] & free_squares;
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* captures */
temp_move = king_table[from] & game->board[PIECES][BLACK];
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
/* TODO: add castling moves here after writing is_attacked function */
} else { /* to_move == BLACK */
/***************/
/* BLACK PAWNS */
/***************/
temp_move = step_down(game->board[PAWNS][BLACK]) & free_squares;
temp_move2 = temp_move;
/* single pushes */
while (temp_move)
{
to = bit_scan_forward(temp_move);
if (to/8 == 0)
{ /* time for a promotion */
game->move_buffer[move_count++] = create_move(to+8,to,BISHOP_PROMO_FLAG);
game->move_buffer[move_count++] = create_move(to+8,to,KNIGHT_PROMO_FLAG);
game->move_buffer[move_count++] = create_move(to+8,to,ROOK_PROMO_FLAG);
game->move_buffer[move_count++] = create_move(to+8,to,QUEEN_PROMO_FLAG);
} else game->move_buffer[move_count++] = create_move(to+8,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* double pushes */
temp_move2 = step_down(temp_move2) & free_squares & rank5;
while (temp_move2)
{
to = bit_scan_forward(temp_move2);
game->move_buffer[move_count++] = create_move(to+16,to,DOUBLE_PAWN_PUSH_FLAG);
temp_move2 &= temp_move2 - 1;
}
/* captures */
/* TODO: add en passante capture */
temp_piece = game->board[PAWNS][BLACK];
while (temp_piece)
{
from = bit_scan_forward(temp_piece);
temp_move = pawn_attacks[BLACK][from] & game->board[PIECES][WHITE];
while (temp_move)
{
to = bit_scan_forward(temp_move);
if (to/8 == 7)
{ /* time for a promotion */
game->move_buffer[move_count++] = create_move(from,to,BISHOP_PROMO_CAPTURE_FLAG);
game->move_buffer[move_count++] = create_move(from,to,KNIGHT_PROMO_CAPTURE_FLAG);
game->move_buffer[move_count++] = create_move(from,to,ROOK_PROMO_CAPTURE_FLAG);
game->move_buffer[move_count++] = create_move(from,to,QUEEN_PROMO_CAPTURE_FLAG);
} else game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
temp_piece &= temp_piece - 1;
}
/*****************/
/* BLACK KNIGHTS */
/*****************/
temp_piece = game->board[KNIGHTS][BLACK];
while (temp_piece)
{
from = bit_scan_forward(temp_piece);
/* quiets */
temp_move = knight_table[from] & free_squares;
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* captures */
temp_move = knight_table[from] & game->board[PIECES][WHITE];
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
temp_piece &= temp_piece - 1;
}
/*****************/
/* BLACK BISHOPS */
/*****************/
temp_piece = game->board[BISHOPS][BLACK];
while (temp_piece)
{
from = bit_scan_forward(temp_piece);
temp_move2 = get_bishop_attacks(game->board[OCCUPIED][1], from);
/* quiets */
temp_move = temp_move2 & free_squares;
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* captures */
temp_move = temp_move2 & game->board[PIECES][WHITE];
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
temp_piece &= temp_piece - 1;
}
/***************/
/* BLACK ROOKS */
/***************/
temp_piece = game->board[ROOKS][BLACK];
while (temp_piece)
{
from = bit_scan_forward(temp_piece);
temp_move2 = get_rook_attacks(game->board[OCCUPIED][1], from);
/* quiets */
temp_move = temp_move2 & free_squares;
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* captures */
temp_move = temp_move2 & game->board[PIECES][WHITE];
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
temp_piece &= temp_piece - 1;
}
/****************/
/* BLACK QUEENS */
/****************/
temp_piece = game->board[QUEENS][BLACK];
while (temp_piece)
{
from = bit_scan_forward(temp_piece);
temp_move2 = get_queen_attacks(game->board[OCCUPIED][1], from);
/* quiets */
temp_move = temp_move2 & free_squares;
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* captures */
temp_move = temp_move2 & game->board[PIECES][WHITE];
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
temp_piece &= temp_piece - 1;
}
/**************/
/* BLACK KINGS */
/**************/
temp_piece = game->board[KINGS][BLACK];
from = bit_scan_forward(temp_piece);
/* quiets */
temp_move = king_table[from] & free_squares;
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,QUIET_FLAG);
temp_move &= temp_move - 1;
}
/* captures */
temp_move = king_table[from] & game->board[PIECES][WHITE];
while (temp_move)
{
to = bit_scan_forward(temp_move);
game->move_buffer[move_count++] = create_move(from,to,CAPTURE_FLAG);
temp_move &= temp_move - 1;
}
}
return move_count;
}
