bool mateThreat = false;
bool isCheck = pos.is_check();
+ bool useNullMove = ( allowNullmove
+ && depth > OnePly
+ && !isCheck
+ && !value_is_mate(beta)
+ && ok_to_do_nullmove(pos)
+ && approximateEval >= beta - NullMoveMargin);
+
// Null move search
- if ( allowNullmove
- && depth > OnePly
- && !isCheck
- && !value_is_mate(beta)
- && ok_to_do_nullmove(pos)
- && approximateEval >= beta - NullMoveMargin)
+ if (useNullMove)
{
ss[ply].currentMove = MOVE_NULL;
}
}
// Null move search not allowed, try razoring
- else if ( !value_is_mate(beta)
- && depth < RazorDepth
- && approximateEval < beta - RazorApprMargins[int(depth) - 2]
- && ss[ply - 1].currentMove != MOVE_NULL
- && ttMove == MOVE_NONE
- && !pos.has_pawn_on_7th(pos.side_to_move()))
+ if ( !useNullMove
+ && !value_is_mate(beta)
+ && depth < RazorDepth
+ && approximateEval < beta - RazorApprMargins[int(depth) - 2]
+ && ss[ply - 1].currentMove != MOVE_NULL
+ && ttMove == MOVE_NONE
+ && !pos.has_pawn_on_7th(pos.side_to_move()))
{
Value v = qsearch(pos, ss, beta-1, beta, Depth(0), ply, threadID);
if (v < beta - RazorMargins[int(depth) - 2])