bool is_pinned(const board_t * board, int square, int colour) {
int from, to;
int inc;
int sq, piece;
ASSERT(board!=NULL);
ASSERT(SQUARE_IS_OK(square));
ASSERT(COLOUR_IS_OK(colour));
from = square;
to = KING_POS(board,colour);
inc = DELTA_INC_LINE(to-from);
if (inc == IncNone) return false; // not a line
sq = from;
do sq += inc; while (board->square[sq] == Empty);
if (sq != to) return false; // blocker
sq = from;
do sq -= inc; while ((piece=board->square[sq]) == Empty);
return COLOUR_IS(piece,COLOUR_OPP(colour)) && SLIDER_ATTACK(piece,inc);
}
bool pseudo_is_legal(int move, board_t * board) {
int me, opp;
int from, to;
int piece;
bool legal;
int king;
undo_t undo[1];
ASSERT(move_is_ok(move));
ASSERT(board!=NULL);
// init
me = board->turn;
opp = COLOUR_OPP(me);
from = MOVE_FROM(move);
to = MOVE_TO(move);
piece = board->square[from];
ASSERT(COLOUR_IS(piece,me));
// slow test for en-passant captures
if (MOVE_IS_EN_PASSANT(move)) {
move_do(board,move,undo);
legal = !IS_IN_CHECK(board,me);
move_undo(board,move,undo);
return legal;
}
// king moves (including castle)
if (PIECE_IS_KING(piece)) {
legal = !is_attacked(board,to,opp);
if (DEBUG) {
ASSERT(board->square[from]==piece);
board->square[from] = Empty;
ASSERT(legal==!is_attacked(board,to,opp));
board->square[from] = piece;
}
return legal;
}
// pins
if (is_pinned(board,from,me)) {
king = KING_POS(board,me);
return DELTA_INC_LINE(king-to) == DELTA_INC_LINE(king-from); // does not discover the line
}
return true;
}
int see_square(const board_t * board, int to, int colour) {
int att, def;
alists_t alists[1];
alist_t * alist;
int piece_value;
int piece;
ASSERT(board!=NULL);
ASSERT(SQUARE_IS_OK(to));
ASSERT(COLOUR_IS_OK(colour));
ASSERT(COLOUR_IS(board->square[to],COLOUR_OPP(colour)));
// build attacker list
att = colour;
alist = alists->alist[att];
ALIST_CLEAR(alist);
alist_build(alist,board,to,att);
if (alist->size == 0) return 0; // no attacker => stop SEE
// build defender list
def = COLOUR_OPP(att);
alist = alists->alist[def];
ALIST_CLEAR(alist);
alist_build(alist,board,to,def);
// captured piece
piece = board->square[to];
ASSERT(piece_is_ok(piece));
ASSERT(COLOUR_IS(piece,def));
piece_value = VALUE_PIECE(piece);
// SEE search
return see_rec(alists,board,att,to,piece_value);
}
static void find_pins(int list[], const board_t * board) {
int me, opp;
int king;
const sq_t * ptr;
int from;
int piece;
int delta;
int inc;
int sq;
int capture;
int pin;
ASSERT(list!=NULL);
ASSERT(board!=NULL);
// init
me = board->turn;
opp = COLOUR_OPP(me);
king = KING_POS(board,opp);
for (ptr = &board->piece[me][1]; (from=*ptr) != SquareNone; ptr++) { // HACK: no king
piece = board->square[from];
delta = king - from;
ASSERT(delta_is_ok(delta));
if (PSEUDO_ATTACK(piece,delta)) {
ASSERT(PIECE_IS_SLIDER(piece));
inc = DELTA_INC_LINE(delta);
ASSERT(inc!=IncNone);
ASSERT(SLIDER_ATTACK(piece,inc));
sq = from;
do sq += inc;
while ((capture=board->square[sq]) == Empty);
ASSERT(sq!=king);
if (COLOUR_IS(capture,me)) {
pin = sq;
do sq += inc;
while (board->square[sq] == Empty);
if (sq == king) *list++ = pin;
}
}
}
*list = SquareNone;
}
void move_undo(int move, const undo_t * undo) {
int me;
int from, to;
int piece,pos;
ASSERT(move_is_ok(move));
ASSERT(undo!=NULL);
// init
me = undo->turn;
from = MOVE_FROM(move);
to = MOVE_TO(move);
piece = Square[to];
pos=piece & 31;
ASSERT(COLOUR_IS(piece,me));
Square[from]=piece;
Piece[pos]=from;
BitRanks[from>>4] ^= g_BitRankMask[from];
BitFiles[from & 0xf]^= g_BitFileMask[from];
if(undo->capture)//吃子更新
{
Square[to]=undo->capture_piece;
Piece[undo->capture_piece & 31]=to;
Piece_size[PIECE_COLOUR(undo->capture_piece)]++;
Number[PieceTo32[undo->capture_piece & 31]]++;
}else
{
Square[to]=Empty;
BitRanks[to>>4] ^= g_BitRankMask[to];
BitFiles[to&0xf]^= g_BitFileMask[to];
}
Turn = undo->turn;
Opening = undo->opening;
Endgame = undo->endgame;
Key = undo->key;
Lock = undo->lock;
Sp--;
}
bool move_is_check(int move, board_t * board) {
undo_t undo[1];
bool check;
int me, opp, king;
int from, to, piece;
ASSERT(move_is_ok(move));
ASSERT(board!=NULL);
// slow test for complex moves
if (MOVE_IS_SPECIAL(move)) {
move_do(board,move,undo);
check = IS_IN_CHECK(board,board->turn);
move_undo(board,move,undo);
return check;
}
// init
me = board->turn;
opp = COLOUR_OPP(me);
king = KING_POS(board,opp);
from = MOVE_FROM(move);
to = MOVE_TO(move);
piece = board->square[from];
ASSERT(COLOUR_IS(piece,me));
// direct check
if (PIECE_ATTACK(board,piece,to,king)) return true;
// indirect check
if (is_pinned(board,from,opp)
&& DELTA_INC_LINE(king-to) != DELTA_INC_LINE(king-from)) {
return true;
}
return false;
}
static int see_rec(alists_t * alists, const board_t * board, int colour, int to, int piece_value) {
int from, piece;
int value;
ASSERT(alists!=NULL);
ASSERT(board!=NULL);
ASSERT(COLOUR_IS_OK(colour));
ASSERT(SQUARE_IS_OK(to));
ASSERT(piece_value>0);
// find the least valuable attacker
from = alist_pop(alists->alist[colour],board);
if (from == SquareNone) return 0; // no more attackers
// find hidden attackers
alists_hidden(alists,board,from,to);
// calculate the capture value
value = +piece_value; // captured piece
if (value == ValueKing) return value; // do not allow an answer to a king capture
piece = board->square[from];
ASSERT(piece_is_ok(piece));
ASSERT(COLOUR_IS(piece,colour));
piece_value = VALUE_PIECE(piece);
// promote
if (piece_value == ValuePawn && SQUARE_IS_PROMOTE(to)) { // HACK: PIECE_IS_PAWN(piece)
ASSERT(PIECE_IS_PAWN(piece));
piece_value = ValueQueen;
value += ValueQueen - ValuePawn;
}
value -= see_rec(alists,board,COLOUR_OPP(colour),to,piece_value);
if (value < 0) value = 0;
return value;
}
int see_move(int move, const board_t * board) {
int att, def;
int from, to;
alists_t alists[1];
int value, piece_value;
int piece, capture;
alist_t * alist;
int pos;
ASSERT(move_is_ok(move));
ASSERT(board!=NULL);
// init
from = MOVE_FROM(move);
to = MOVE_TO(move);
// move the piece
piece_value = 0;
piece = board->square[from];
ASSERT(piece_is_ok(piece));
att = PIECE_COLOUR(piece);
def = COLOUR_OPP(att);
// promote
if (MOVE_IS_PROMOTE(move)) {
ASSERT(PIECE_IS_PAWN(piece));
piece = move_promote(move);
ASSERT(piece_is_ok(piece));
ASSERT(COLOUR_IS(piece,att));
}
piece_value += VALUE_PIECE(piece);
// clear attacker lists
ALIST_CLEAR(alists->alist[Black]);
ALIST_CLEAR(alists->alist[White]);
// find hidden attackers
alists_hidden(alists,board,from,to);
// capture the piece
value = 0;
capture = board->square[to];
if (capture != Empty) {
ASSERT(piece_is_ok(capture));
ASSERT(COLOUR_IS(capture,def));
value += VALUE_PIECE(capture);
}
// promote
if (MOVE_IS_PROMOTE(move)) {
value += VALUE_PIECE(piece) - ValuePawn;
}
// en-passant
if (MOVE_IS_EN_PASSANT(move)) {
ASSERT(value==0);
ASSERT(PIECE_IS_PAWN(board->square[SQUARE_EP_DUAL(to)]));
value += ValuePawn;
alists_hidden(alists,board,SQUARE_EP_DUAL(to),to);
}
// build defender list
alist = alists->alist[def];
alist_build(alist,board,to,def);
if (alist->size == 0) return value; // no defender => stop SEE
// build attacker list
alist = alists->alist[att];
alist_build(alist,board,to,att);
// remove the moved piece (if it's an attacker)
for (pos = 0; pos < alist->size && alist->square[pos] != from; pos++)
;
if (pos < alist->size) alist_remove(alist,pos);
// SEE search
value -= see_rec(alists,board,def,to,piece_value);
return value;
}
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;
}
bool capture_is_good(int move, const board_t * board, bool in_pv) {
#else
static bool capture_is_good(int move, const board_t * board, bool in_pv) {
#endif
int piece, capture;
int see_value; // WHM 11/22/08
ASSERT(move_is_ok(move));
ASSERT(board!=NULL);
ASSERT(move_is_tactical(move,board));
// special cases
if (MOVE_IS_EN_PASSANT(move)) return true;
if (move_is_under_promote(move)) return false; // REMOVE ME? Keep, looks good to me. WHM;
// if (MOVE_IS_PROMOTE(move)) return true; // WHM; promote-to-queen, measures a little weaker
// too many garbage lines going nuts.
// captures and queen promotes
capture = board->square[MOVE_TO(move)];
piece = board->square[MOVE_FROM(move)];
if (capture != Empty) {
// capture
ASSERT(move_is_capture(move,board));
if (MOVE_IS_PROMOTE(move)) return true; // capture a piece on Rank8 and promote to queen
if (VALUE_PIECE(capture) >= VALUE_PIECE(piece)) return true;
}
// return see_move(move,board) >= 0; WHM 11/22/08
// WHM 11/22/08 START
see_value = see_move(move,board);
if (see_value >= 0) return true;
if (TryNodePVQueenPromotes) {
if (in_pv && MOVE_IS_PROMOTE(move)) {
ASSERT(!move_is_under_promote(move));
return true; // WHM:
}
}
if (TryKingAttackSacs || TryKingBoxSacs || TryPasserSacs) {
if (in_pv && see_value > -ValueBishop && capture != Empty) {
ASSERT(COLOUR_IS(capture,COLOUR_OPP(board->turn)));
// king attack sacs.
if (TryKingAttackSacs) {
if (narrow_piece_attack_king(board, piece, MOVE_TO(move), KING_POS(board,COLOUR_OPP(board->turn)))) {
return true;
}
}
// sacrifice attacks around the narrow/close king box can be examined more fully. Rybka lessons.
if (TryKingBoxSacs) {
if (DISTANCE(MOVE_TO(move),KING_POS(board,COLOUR_OPP(board->turn))) <= 1) {
return true;
}
}
// passer sacrifices...
if (TryPasserSacs) {
if (PIECE_IS_PAWN(capture) && PAWN_RANK(MOVE_TO(move),COLOUR_OPP(board->turn)) >= Rank6) {
return true;
}
}
}
} // WHM 11/22/08 END
return false;
}
bool board_is_ok(const board_t * board) {
int sq, piece, colour;
int size, pos;
if (board == NULL) return false;
// optional heavy DEBUG mode
if (!UseSlowDebug) return true;
// squares
for (sq = 0; sq < SquareNb; sq++) {
piece = board->square[sq];
pos = board->pos[sq];
if (SQUARE_IS_OK(sq)) {
// inside square
if (piece == Empty) {
if (pos != -1) return false;
} else {
if (!piece_is_ok(piece)) return false;
if (!PIECE_IS_PAWN(piece)) {
colour = PIECE_COLOUR(piece);
if (pos < 0 || pos >= board->piece_size[colour]) return false;
if (board->piece[colour][pos] != sq) return false;
} else { // pawn
if (SQUARE_IS_PROMOTE(sq)) return false;
colour = PIECE_COLOUR(piece);
if (pos < 0 || pos >= board->pawn_size[colour]) return false;
if (board->pawn[colour][pos] != sq) return false;
}
}
} else {
// edge square
if (piece != Edge) return false;
if (pos != -1) return false;
}
}
// piece lists
for (colour = 0; colour < ColourNb; colour++) {
// piece list
size = board->piece_size[colour];
if (size < 1 || size > 16) return false;
for (pos = 0; pos < size; pos++) {
sq = board->piece[colour][pos];
if (!SQUARE_IS_OK(sq)) return false;
if (board->pos[sq] != pos) return false;
piece = board->square[sq];
if (!COLOUR_IS(piece,colour)) return false;
if (pos == 0 && !PIECE_IS_KING(piece)) return false;
if (pos != 0 && PIECE_IS_KING(piece)) return false;
if (pos != 0 && PIECE_ORDER(piece) > PIECE_ORDER(board->square[board->piece[colour][pos-1]])) {
return false;
}
}
sq = board->piece[colour][size];
if (sq != SquareNone) return false;
// pawn list
size = board->pawn_size[colour];
if (size < 0 || size > 8) return false;
for (pos = 0; pos < size; pos++) {
sq = board->pawn[colour][pos];
if (!SQUARE_IS_OK(sq)) return false;
if (SQUARE_IS_PROMOTE(sq)) return false;
if (board->pos[sq] != pos) return false;
piece = board->square[sq];
if (!COLOUR_IS(piece,colour)) return false;
if (!PIECE_IS_PAWN(piece)) return false;
}
sq = board->pawn[colour][size];
if (sq != SquareNone) return false;
// piece total
if (board->piece_size[colour] + board->pawn_size[colour] > 16) return false;
}
// material
if (board->piece_nb != board->piece_size[White] + board->pawn_size[White]
+ board->piece_size[Black] + board->pawn_size[Black]) {
return false;
}
if (board->number[WhitePawn12] != board->pawn_size[White]) return false;
if (board->number[BlackPawn12] != board->pawn_size[Black]) return false;
if (board->number[WhiteKing12] != 1) return false;
if (board->number[BlackKing12] != 1) return false;
// misc
if (!COLOUR_IS_OK(board->turn)) return false;
if (board->ply_nb < 0) return false;
if (board->sp < board->ply_nb) return false;
if (board->cap_sq != SquareNone && !SQUARE_IS_OK(board->cap_sq)) return false;
if (board->opening != board_opening(board)) return false;
if (board->endgame != board_endgame(board)) return false;
if (board->key != hash_key(board)) return false;
if (board->pawn_key != hash_pawn_key(board)) return false;
if (board->material_key != hash_material_key(board)) return false;
return true;
}
void board_init_list(board_t * board) {
int sq_64, sq, piece;
int colour, pos;
int i, size;
int square;
int order;
int file;
ASSERT(board!=NULL);
// init
for (sq = 0; sq < SquareNb; sq++) {
board->pos[sq] = -1;
}
board->piece_nb = 0;
for (piece = 0; piece < 12; piece++) board->number[piece] = 0;
// piece lists
for (colour = 0; colour < ColourNb; colour++) {
// piece list
pos = 0;
for (sq_64 = 0; sq_64 < 64; sq_64++) {
sq = SQUARE_FROM_64(sq_64);
piece = board->square[sq];
if (piece != Empty && !piece_is_ok(piece)) my_fatal("board_init_list(): illegal position\n");
if (COLOUR_IS(piece,colour) && !PIECE_IS_PAWN(piece)) {
if (pos >= 16) my_fatal("board_init_list(): illegal position\n");
ASSERT(pos>=0&&pos<16);
board->pos[sq] = pos;
board->piece[colour][pos] = sq;
pos++;
board->piece_nb++;
board->number[PIECE_TO_12(piece)]++;
}
}
if (board->number[COLOUR_IS_WHITE(colour)?WhiteKing12:BlackKing12] != 1) my_fatal("board_init_list(): illegal position\n");
ASSERT(pos>=1&&pos<=16);
board->piece[colour][pos] = SquareNone;
board->piece_size[colour] = pos;
// MV sort
size = board->piece_size[colour];
for (i = 1; i < size; i++) {
square = board->piece[colour][i];
piece = board->square[square];
order = PIECE_ORDER(piece);
for (pos = i; pos > 0 && order > PIECE_ORDER(board->square[(sq=board->piece[colour][pos-1])]); pos--) {
ASSERT(pos>0&&pos<size);
board->piece[colour][pos] = sq;
ASSERT(board->pos[sq]==pos-1);
board->pos[sq] = pos;
}
ASSERT(pos>=0&&pos<size);
board->piece[colour][pos] = square;
ASSERT(board->pos[square]==i);
board->pos[square] = pos;
}
// debug
if (DEBUG) {
for (i = 0; i < board->piece_size[colour]; i++) {
sq = board->piece[colour][i];
ASSERT(board->pos[sq]==i);
if (i == 0) { // king
ASSERT(PIECE_IS_KING(board->square[sq]));
} else {
ASSERT(!PIECE_IS_KING(board->square[sq]));
ASSERT(PIECE_ORDER(board->square[board->piece[colour][i]])<=PIECE_ORDER(board->square[board->piece[colour][i-1]]));
}
}
}
// pawn list
for (file = 0; file < FileNb; file++) {
board->pawn_file[colour][file] = 0;
}
pos = 0;
for (sq_64 = 0; sq_64 < 64; sq_64++) {
sq = SQUARE_FROM_64(sq_64);
piece = board->square[sq];
if (COLOUR_IS(piece,colour) && PIECE_IS_PAWN(piece)) {
if (pos >= 8 || SQUARE_IS_PROMOTE(sq)) my_fatal("board_init_list(): illegal position\n");
ASSERT(pos>=0&&pos<8);
board->pos[sq] = pos;
board->pawn[colour][pos] = sq;
pos++;
board->piece_nb++;
board->number[PIECE_TO_12(piece)]++;
board->pawn_file[colour][SQUARE_FILE(sq)] |= BIT(PAWN_RANK(sq,colour));
}
}
ASSERT(pos>=0&&pos<=8);
board->pawn[colour][pos] = SquareNone;
board->pawn_size[colour] = pos;
if (board->piece_size[colour] + board->pawn_size[colour] > 16) my_fatal("board_init_list(): illegal position\n");
}
// last square
board->cap_sq = SquareNone;
// PST
board->opening = board_opening(board);
board->endgame = board_endgame(board);
// hash key
for (i = 0; i < board->ply_nb; i++) board->stack[i] = 0; // HACK
board->sp = board->ply_nb;
board->key = hash_key(board);
board->pawn_key = hash_pawn_key(board);
board->material_key = hash_material_key(board);
// legality
if (!board_is_legal(board)) my_fatal("board_init_list(): illegal position\n");
// debug
ASSERT(board_is_ok(board));
}
void move_do(board_t * board, int move, undo_t * undo) {
int me, opp;
int from, to;
int piece, pos, capture;
int old_flags, new_flags;
int delta;
int sq;
int pawn, rook;
ASSERT(board!=NULL);
ASSERT(move_is_ok(move));
ASSERT(undo!=NULL);
ASSERT(board_is_legal(board));
// initialise undo
undo->capture = false;
undo->turn = board->turn;
undo->flags = board->flags;
undo->ep_square = board->ep_square;
undo->ply_nb = board->ply_nb;
undo->cap_sq = board->cap_sq;
undo->opening = board->opening;
undo->endgame = board->endgame;
undo->key = board->key;
undo->pawn_key = board->pawn_key;
undo->material_key = board->material_key;
// init
me = board->turn;
opp = COLOUR_OPP(me);
from = MOVE_FROM(move);
to = MOVE_TO(move);
piece = board->square[from];
ASSERT(COLOUR_IS(piece,me));
// update key stack
ASSERT(board->sp<StackSize);
board->stack[board->sp++] = board->key;
// update turn
board->turn = opp;
board->key ^= RANDOM_64(RandomTurn);
// update castling rights
old_flags = board->flags;
new_flags = old_flags & CastleMask[from] & CastleMask[to];
board->flags = new_flags;
board->key ^= Castle64[new_flags^old_flags]; // HACK
// update en-passant square
if ((sq=board->ep_square) != SquareNone) {
board->key ^= RANDOM_64(RandomEnPassant+SQUARE_FILE(sq)-FileA);
board->ep_square = SquareNone;
}
if (PIECE_IS_PAWN(piece)) {
delta = to - from;
if (delta == +32 || delta == -32) {
pawn = PAWN_MAKE(opp);
if (board->square[to-1] == pawn || board->square[to+1] == pawn) {
board->ep_square = (from + to) / 2;
board->key ^= RANDOM_64(RandomEnPassant+SQUARE_FILE(to)-FileA);
}
}
}
// update move number (captures are handled later)
board->ply_nb++;
if (PIECE_IS_PAWN(piece)) board->ply_nb = 0; // conversion
// update last square
board->cap_sq = SquareNone;
// remove the captured piece
sq = to;
if (MOVE_IS_EN_PASSANT(move)) sq = SQUARE_EP_DUAL(sq);
if ((capture=board->square[sq]) != Empty) {
ASSERT(COLOUR_IS(capture,opp));
ASSERT(!PIECE_IS_KING(capture));
undo->capture = true;
undo->capture_square = sq;
undo->capture_piece = capture;
undo->capture_pos = board->pos[sq];
square_clear(board,sq,capture,true);
board->ply_nb = 0; // conversion
board->cap_sq = to;
}
// move the piece
if (MOVE_IS_PROMOTE(move)) {
// promote
undo->pawn_pos = board->pos[from];
square_clear(board,from,piece,true);
piece = move_promote(move);
// insert the promote piece in MV order
for (pos = board->piece_size[me]; pos > 0 && piece > board->square[board->piece[me][pos-1]]; pos--) // HACK
;
square_set(board,to,piece,pos,true);
board->cap_sq = to;
} else {
// normal move
square_move(board,from,to,piece,true);
}
// move the rook in case of castling
if (MOVE_IS_CASTLE(move)) {
rook = Rook64 | COLOUR_FLAG(me); // HACK
if (to == G1) {
square_move(board,H1,F1,rook,true);
} else if (to == C1) {
square_move(board,A1,D1,rook,true);
} else if (to == G8) {
square_move(board,H8,F8,rook,true);
} else if (to == C8) {
square_move(board,A8,D8,rook,true);
} else {
ASSERT(false);
}
}
// debug
ASSERT(board_is_ok(board));
}
void move_undo(board_t * board, int move, const undo_t * undo) {
int me;
int from, to;
int piece, pos;
int rook;
ASSERT(board!=NULL);
ASSERT(move_is_ok(move));
ASSERT(undo!=NULL);
// init
me = undo->turn;
from = MOVE_FROM(move);
to = MOVE_TO(move);
piece = board->square[to];
ASSERT(COLOUR_IS(piece,me));
// castle
if (MOVE_IS_CASTLE(move)) {
rook = Rook64 | COLOUR_FLAG(me); // HACK
if (to == G1) {
square_move(board,F1,H1,rook,false);
} else if (to == C1) {
square_move(board,D1,A1,rook,false);
} else if (to == G8) {
square_move(board,F8,H8,rook,false);
} else if (to == C8) {
square_move(board,D8,A8,rook,false);
} else {
ASSERT(false);
}
}
// move the piece backward
if (MOVE_IS_PROMOTE(move)) {
// promote
ASSERT(piece==move_promote(move));
square_clear(board,to,piece,false);
piece = PAWN_MAKE(me);
pos = undo->pawn_pos;
square_set(board,from,piece,pos,false);
} else {
// normal move
square_move(board,to,from,piece,false);
}
// put the captured piece back
if (undo->capture) {
square_set(board,undo->capture_square,undo->capture_piece,undo->capture_pos,false);
}
// update board info
board->turn = undo->turn;
board->flags = undo->flags;
board->ep_square = undo->ep_square;
board->ply_nb = undo->ply_nb;
board->cap_sq = undo->cap_sq;
board->opening = undo->opening;
board->endgame = undo->endgame;
board->key = undo->key;
board->pawn_key = undo->pawn_key;
board->material_key = undo->material_key;
// update key stack
ASSERT(board->sp>0);
board->sp--;
// debug
ASSERT(board_is_ok(board));
ASSERT(board_is_legal(board));
}
bool move_is_pseudo(int move, board_t * board) {
int me, opp;
int from, to;
int piece, capture;
int inc, delta;
ASSERT(move_is_ok(move));
ASSERT(board!=NULL);
ASSERT(!board_is_check(board));
// special cases
if (MOVE_IS_SPECIAL(move)) {
return move_is_pseudo_debug(move,board);
}
ASSERT((move&~07777)==0);
// init
me = board->turn;
opp = COLOUR_OPP(board->turn);
// from
from = MOVE_FROM(move);
ASSERT(SQUARE_IS_OK(from));
piece = board->square[from];
if (!COLOUR_IS(piece,me)) return false;
ASSERT(piece_is_ok(piece));
// to
to = MOVE_TO(move);
ASSERT(SQUARE_IS_OK(to));
capture = board->square[to];
if (COLOUR_IS(capture,me)) return false;
// move
if (PIECE_IS_PAWN(piece)) {
if (SQUARE_IS_PROMOTE(to)) return false;
inc = PAWN_MOVE_INC(me);
delta = to - from;
ASSERT(delta_is_ok(delta));
if (capture == Empty) {
// pawn push
if (delta == inc) return true;
if (delta == (2*inc)
&& PAWN_RANK(from,me) == Rank2
&& board->square[from+inc] == Empty) {
return true;
}
} else {
// pawn capture
if (delta == (inc-1) || delta == (inc+1)) return true;
}
} else {
if (PIECE_ATTACK(board,piece,from,to)) return true;
}
return false;
}