// When failing high/low give some update (without cluttering
// the UI) before a re-search.
- if ( (bestValue <= alpha || bestValue >= beta)
+ if ( multiPV == 1
+ && (bestValue <= alpha || bestValue >= beta)
&& Time::now() - SearchTime > 3000)
sync_cout << uci_pv(pos, depth, alpha, beta) << sync_endl;
}
// Step 7. Futility pruning: child node (skipped when in check)
- if ( !PvNode
+ if ( !RootNode
&& depth < 7 * ONE_PLY
&& eval - futility_margin(depth) >= beta
&& eval < VALUE_KNOWN_WIN // Do not return unproven wins
// Update the current move (this must be done after singular extension search)
newDepth = depth - ONE_PLY + extension;
- // Step 13. Pruning at shallow depth (exclude PV nodes)
- if ( !PvNode
- && !captureOrPromotion
+ // Step 13. Pruning at shallow depth
+ if ( !captureOrPromotion
&& !inCheck
&& !dangerous
&& bestValue > VALUE_MATED_IN_MAX_PLY)
: pos.gives_check(move, ci);
// Futility pruning
- if ( !PvNode
- && !InCheck
+ if ( !InCheck
&& !givesCheck
&& futilityBase > -VALUE_KNOWN_WIN
&& !pos.advanced_pawn_push(move))
futilityValue = futilityBase + PieceValue[EG][pos.piece_on(to_sq(move))];
- if (futilityValue < beta)
+ if (futilityValue <= alpha)
{
bestValue = std::max(bestValue, futilityValue);
continue;
}
- if (futilityBase < beta && pos.see(move) <= VALUE_ZERO)
+ if (futilityBase <= alpha && pos.see(move) <= VALUE_ZERO)
{
bestValue = std::max(bestValue, futilityBase);
continue;
&& !pos.can_castle(pos.side_to_move());
// Don't search moves with negative SEE values
- if ( !PvNode
- && (!InCheck || evasionPrunable)
+ if ( (!InCheck || evasionPrunable)
&& type_of(move) != PROMOTION
&& pos.see_sign(move) < VALUE_ZERO)
continue;