else if (d == Depth(0))
phasePtr = QsearchWithChecksPhaseTable;
else
+ {
phasePtr = QsearchWithoutChecksPhaseTable;
+ // Skip TT move if is not a capture or a promotion, this avoids
+ // qsearch tree explosion due to a possible perpetual check or
+ // similar rare cases when TT table is full.
+ if (ttm != MOVE_NONE && !pos.move_is_capture_or_promotion(ttm))
+ searchTT = ttMoves[0].move = MOVE_NONE;
+ }
+
phasePtr += !searchTT - 1;
go_next_phase();
}
Move m;
Piece piece;
Square from, to;
- int hs;
for (MoveStack* cur = moves; cur != lastMove; cur++)
{
from = move_from(m);
to = move_to(m);
piece = pos.piece_on(from);
- hs = H.move_ordering_score(piece, to);
-
- // Ensure history is always preferred to pst
- if (hs > 0)
- hs += 1000;
-
- // pst based scoring
- cur->score = hs + mg_value(pos.pst_delta(piece, from, to));
+ cur->score = H.move_ordering_score(piece, to);
}
}
/// are no more moves left.
/// It picks the move with the biggest score from a list of generated moves taking
/// care not to return the tt move if has already been searched previously.
+/// Note that this function is not thread safe so should be lock protected by
+/// caller when accessed through a shared MovePicker object.
Move MovePicker::get_next_move() {
}
}
-/// A variant of get_next_move() which takes a lock as a parameter, used to
-/// prevent multiple threads from picking the same move at a split point.
-
-Move MovePicker::get_next_move(Lock &lock) {
-
- lock_grab(&lock);
-
- // Note that it is safe to call many times
- // get_next_move() when phase == PH_STOP
- Move m = get_next_move();
-
- lock_release(&lock);
- return m;
-}