&& ttMove == MOVE_NONE
&& (PvNode || (!inCheck && ss->staticEval + Value(256) >= beta)))
{
- Depth d = (PvNode ? depth - 2 * ONE_PLY : depth / 2);
+ Depth d = depth - 2 * ONE_PLY - (PvNode ? DEPTH_ZERO : depth / 4);
ss->skipNullMove = true;
search<PvNode ? PV : NonPV>(pos, ss, alpha, beta, d);
&& !captureOrPromotion
&& !inCheck
&& !dangerous
- && move != ttMove)
+ && move != ttMove
+ && bestValue > VALUE_MATED_IN_MAX_PLY)
{
// Move count based pruning
if ( depth < 16 * ONE_PLY
// but fixing this made program slightly weaker.
Depth predictedDepth = newDepth - reduction<PvNode>(depth, moveCount);
futilityValue = ss->staticEval + ss->evalMargin + futility_margin(predictedDepth, moveCount)
- + Gain[pos.piece_moved(move)][to_sq(move)];
+ + 2 * Gain[pos.piece_moved(move)][to_sq(move)];
if (futilityValue < beta)
{
+ bestValue = std::max(bestValue, futilityValue);
+
if (SpNode)
+ {
splitPoint->mutex.lock();
-
+ if (bestValue > splitPoint->bestValue)
+ splitPoint->bestValue = bestValue;
+ }
continue;
}
// Prune moves with negative SEE at low depths
- if ( predictedDepth < 3 * ONE_PLY
+ if ( predictedDepth < 4 * ONE_PLY
&& pos.see_sign(move) < 0)
{
if (SpNode)
if (pos.is_draw<true>() || ss->ply > MAX_PLY)
return DrawValue[pos.side_to_move()];
+ // Decide whether or not to include checks, this fixes also the type of
+ // TT entry depth that we are going to use. Note that in qsearch we use
+ // only two types of depth in TT: DEPTH_QS_CHECKS or DEPTH_QS_NO_CHECKS.
+ ttDepth = InCheck || depth >= DEPTH_QS_CHECKS ? DEPTH_QS_CHECKS
+ : DEPTH_QS_NO_CHECKS;
+
// Transposition table lookup. At PV nodes, we don't use the TT for
// pruning, but only for move ordering.
posKey = pos.key();
ttMove = tte ? tte->move() : MOVE_NONE;
ttValue = tte ? value_from_tt(tte->value(),ss->ply) : VALUE_NONE;
- // Decide whether or not to include checks, this fixes also the type of
- // TT entry depth that we are going to use. Note that in qsearch we use
- // only two types of depth in TT: DEPTH_QS_CHECKS or DEPTH_QS_NO_CHECKS.
- ttDepth = InCheck || depth >= DEPTH_QS_CHECKS ? DEPTH_QS_CHECKS
- : DEPTH_QS_NO_CHECKS;
if ( tte
&& tte->depth() >= ttDepth
&& ttValue != VALUE_NONE // Only in case of TT access race