enum NodeType { Root, PV, NonPV };
// Razoring and futility margin based on depth
- inline Value razor_margin(Depth d) { return Value(512 + 32 * d); }
- inline Value futility_margin(Depth d) { return Value(200 * d); }
+ Value razor_margin(Depth d) { return Value(512 + 32 * d); }
+ Value futility_margin(Depth d) { return Value(200 * d); }
// Futility and reductions lookup tables, initialized at startup
int FutilityMoveCounts[2][16]; // [improving][depth]
Depth Reductions[2][2][64][64]; // [pv][improving][depth][moveNumber]
- template <bool PvNode> inline Depth reduction(bool i, Depth d, int mn) {
+ template <bool PvNode> Depth reduction(bool i, Depth d, int mn) {
return Reductions[PvNode][i][std::min(d, 63 * ONE_PLY)][std::min(mn, 63)];
}
}
ss->currentMove = move;
- if (!SpNode && !captureOrPromotion && quietCount < 64)
- quietsSearched[quietCount++] = move;
// Step 14. Make the move
pos.do_move(move, st, givesCheck);
ss->reduction = reduction<PvNode>(improving, depth, moveCount);
if ( (!PvNode && cutNode)
- || History[pos.piece_on(to_sq(move))][to_sq(move)] < VALUE_ZERO
- || ( History[pos.piece_on(to_sq(move))][to_sq(move)]
- + CounterMovesHistory[pos.piece_on(prevMoveSq)][prevMoveSq]
- [pos.piece_on(to_sq(move))][to_sq(move)] < VALUE_ZERO))
+ || ( History[pos.piece_on(to_sq(move))][to_sq(move)] < VALUE_ZERO
+ && CounterMovesHistory[pos.piece_on(prevMoveSq)][prevMoveSq][pos.piece_on(to_sq(move))][to_sq(move)] <= VALUE_ZERO))
ss->reduction += ONE_PLY;
if (move == countermove)
}
}
+ if (!SpNode && !captureOrPromotion && move != bestMove && quietCount < 64)
+ quietsSearched[quietCount++] = move;
+
// Step 19. Check for splitting the search
if ( !SpNode
&& Threads.size() >= 2
: inCheck ? mated_in(ss->ply) : DrawValue[pos.side_to_move()];
// Quiet best move: update killers, history and countermoves
- else if (bestValue >= beta && !pos.capture_or_promotion(bestMove))
- update_stats(pos, ss, bestMove, depth, quietsSearched, quietCount - 1);
+ else if (bestMove && !pos.capture_or_promotion(bestMove))
+ update_stats(pos, ss, bestMove, depth, quietsSearched, quietCount);
tte->save(posKey, value_to_tt(bestValue, ss->ply),
bestValue >= beta ? BOUND_LOWER :
*pv = MOVE_NONE;
}
- // update_stats() updates killers, history and countermoves stats after a fail-high
- // of a quiet move.
- void update_stats(const Position& pos, Stack* ss, Move move, Depth depth, Move* quiets, int quietsCnt) {
+ // update_stats() updates killers, history, countermove history and
+ // countermoves stats for a quiet best move.
+
+ void update_stats(const Position& pos, Stack* ss, Move move,
+ Depth depth, Move* quiets, int quietsCnt) {
if (ss->killers[0] != move)
{