int SEARCHER::probe_bitbases(int* score,bool both) {
register PLIST current;
int piece[MAX_PIECES],square[MAX_PIECES],count = 0;
#define ADD_PIECE(list,type) { \
current = list; \
while(current) { \
piece[count] = type; \
square[count] = SQ8864(current->sq); \
current = current->next; \
count++; \
} \
};
ADD_PIECE(plist[wking],_WKING);
ADD_PIECE(plist[bking],_BKING);
ADD_PIECE(plist[wqueen],_WQUEEN);
ADD_PIECE(plist[bqueen],_BQUEEN);
ADD_PIECE(plist[wrook],_WROOK);
ADD_PIECE(plist[brook],_BROOK);
ADD_PIECE(plist[wbishop],_WBISHOP);
ADD_PIECE(plist[bbishop],_BBISHOP);
ADD_PIECE(plist[wknight],_WKNIGHT);
ADD_PIECE(plist[bknight],_BKNIGHT);
ADD_PIECE(plist[wpawn],_WPAWN);
ADD_PIECE(plist[bpawn],_BPAWN);
piece[count] = _EMPTY;
square[count] = 0;
score[0] = probe_egbb(player,piece,square);
if(both)
score[1] = probe_egbb(opponent,piece,square);
return (score[0] != _NOTFOUND);
}
//Probe EGBBs:
//Change interanal Stockfish board representaion to
//EGBB board representation and then probe
Value EGBB::probe(const Position& pos, int ply, int depth, int fifty) {
int npieces = pos.count<ALL_PIECES>(WHITE) + pos.count<ALL_PIECES>(BLACK);
int dlimit = depth_limit * ONE_PLY;
int plimit = (npieces < MAX_PIECES) ? ply_limit : ply_limit / 2;
if(is_loaded && (ply > 1) //must be loaded
&& npieces <= MAX_PIECES //maximum 6 pieces
&& (depth >= dlimit || npieces <= 4) //hard depth limit
&& (ply >= plimit || fifty == 0) //ply above threshold or capt/pawn move
);
else
return VALUE_NONE;
//Loop over pieces and fill up piece and square arrays
Square s;
int piece[8],square[8],count = 0;
#define ADD_PIECE(Piece,Col,PieceS) { \
const Square* pl = pos.list<Piece>(Col); \
while ((s = *pl++) != SQ_NONE) { \
piece[count] = PieceS; \
square[count] = s; \
count++; \
} \
};
ADD_PIECE(KING, WHITE, _WKING);
ADD_PIECE(KING, BLACK, _BKING);
ADD_PIECE(QUEEN, WHITE, _WQUEEN);
ADD_PIECE(QUEEN, BLACK, _BQUEEN);
ADD_PIECE(ROOK, WHITE, _WROOK);
ADD_PIECE(ROOK, BLACK, _BROOK);
ADD_PIECE(BISHOP, WHITE, _WBISHOP);
ADD_PIECE(BISHOP, BLACK, _BBISHOP);
ADD_PIECE(KNIGHT, WHITE, _WKNIGHT);
ADD_PIECE(KNIGHT, BLACK, _BKNIGHT);
ADD_PIECE(PAWN, WHITE, _WPAWN);
ADD_PIECE(PAWN, BLACK, _BPAWN);
piece[count] = _EMPTY;
square[count] = pos.ep_square();
//probe and return adjusted value
int score = probe_egbb(
(pos.side_to_move() == WHITE) ? _WHITE : _BLACK,
piece,square);
if(score == _NOTFOUND)
return VALUE_NONE;
else {
tb_hits++;
if(score > 0)
return VALUE_EGBB_WIN - VALUE_EGBB_PLY * ply + (score - 5000);
else if(score < 0)
return -VALUE_EGBB_WIN + VALUE_EGBB_PLY * ply + (score + 5000);
else
return VALUE_DRAW;
}
}