Thread* bestThread = this;
if ( !this->easyMovePlayed
&& Options["MultiPV"] == 1
+ && !Limits.depth
&& !Skill(Options["Skill Level"]).enabled()
&& rootMoves[0].pv[0] != MOVE_NONE)
{
multiPV = std::min(multiPV, rootMoves.size());
// Iterative deepening loop until requested to stop or the target depth is reached.
- while (++rootDepth < DEPTH_MAX && !Signals.stop && (!Limits.depth || rootDepth <= Limits.depth))
+ while (++rootDepth < DEPTH_MAX && !Signals.stop && (!Limits.depth || Threads.main()->rootDepth <= Limits.depth))
{
// Set up the new depths for the helper threads skipping on average every
// 2nd ply (using a half-density matrix).
std::stable_sort(rootMoves.begin(), rootMoves.begin() + PVIdx + 1);
if (!mainThread)
- break;
+ continue;
if (Signals.stop)
sync_cout << "info nodes " << Threads.nodes_searched()
// Stop the search if only one legal move is available, or if all
// of the available time has been used, or if we matched an easyMove
// from the previous search and just did a fast verification.
- const bool F[] = { !mainThread->failedLow,
- bestValue >= mainThread->previousScore };
+ const int F[] = { mainThread->failedLow,
+ bestValue - mainThread->previousScore };
- int improvingFactor = 640 - 160*F[0] - 126*F[1] - 124*F[0]*F[1];
+ int improvingFactor = std::max(229, std::min(715, 357 + 119 * F[0] - 6 * F[1]));
double unstablePvFactor = 1 + mainThread->bestMoveChanges;
bool doEasyMove = rootMoves[0].pv[0] == easyMove
&& mainThread->bestMoveChanges < 0.03
- && Time.elapsed() > Time.optimum() * 25 / 204;
+ && Time.elapsed() > Time.optimum() * 5 / 42;
if ( rootMoves.size() == 1
- || Time.elapsed() > Time.optimum() * unstablePvFactor * improvingFactor / 634
+ || Time.elapsed() > Time.optimum() * unstablePvFactor * improvingFactor / 628
|| (mainThread->easyMovePlayed = doEasyMove))
{
// If we are allowed to ponder do not stop the search now but
Key posKey;
Move ttMove, move, excludedMove, bestMove;
Depth extension, newDepth, predictedDepth;
- Value bestValue, value, ttValue, eval, nullValue, futilityValue;
+ Value bestValue, value, ttValue, eval, nullValue;
bool ttHit, inCheck, givesCheck, singularExtensionNode, improving;
- bool captureOrPromotion, doFullDepthSearch;
+ bool captureOrPromotion, doFullDepthSearch, moveCountPruning;
+ Piece moved_piece;
int moveCount, quietCount;
// Step 1. Initialize node
moves_loop: // When in check search starts from here
Square prevSq = to_sq((ss-1)->currentMove);
- const CounterMoveStats& cmh = CounterMoveHistory[pos.piece_on(prevSq)][prevSq];
+ const CounterMoveStats* cmh = (ss-1)->counterMoves;
+ const CounterMoveStats* fmh = (ss-2)->counterMoves;
+ const CounterMoveStats* fmh2 = (ss-4)->counterMoves;
MovePicker mp(pos, ttMove, depth, ss);
CheckInfo ci(pos);
extension = DEPTH_ZERO;
captureOrPromotion = pos.capture_or_promotion(move);
+ moved_piece = pos.moved_piece(move);
givesCheck = type_of(move) == NORMAL && !ci.dcCandidates
? ci.checkSquares[type_of(pos.piece_on(from_sq(move)))] & to_sq(move)
: pos.gives_check(move, ci);
+ moveCountPruning = depth < 16 * ONE_PLY
+ && moveCount >= FutilityMoveCounts[improving][depth];
+
// Step 12. Extend checks
- if (givesCheck && pos.see_sign(move) >= VALUE_ZERO)
+ if ( givesCheck
+ && ( moveCount == 1
+ || (!moveCountPruning && pos.see_sign(move) >= VALUE_ZERO)))
extension = ONE_PLY;
// Singular extension search. If all moves but one fail low on a search of
&& bestValue > VALUE_MATED_IN_MAX_PLY)
{
// Move count based pruning
- if ( depth < 16 * ONE_PLY
- && moveCount >= FutilityMoveCounts[improving][depth])
+ if (moveCountPruning)
continue;
- // History based pruning
+ // Countermoves based pruning
if ( depth <= 4 * ONE_PLY
&& move != ss->killers[0]
- && thisThread->history[pos.moved_piece(move)][to_sq(move)] < VALUE_ZERO
- && cmh[pos.moved_piece(move)][to_sq(move)] < VALUE_ZERO)
+ && (!cmh || (*cmh )[moved_piece][to_sq(move)] < VALUE_ZERO)
+ && (!fmh || (*fmh )[moved_piece][to_sq(move)] < VALUE_ZERO)
+ && (!fmh2 || (*fmh2)[moved_piece][to_sq(move)] < VALUE_ZERO || (cmh && fmh)))
continue;
predictedDepth = std::max(newDepth - reduction<PvNode>(improving, depth, moveCount), DEPTH_ZERO);
// Futility pruning: parent node
- if (predictedDepth < 7 * ONE_PLY)
- {
- futilityValue = ss->staticEval + futility_margin(predictedDepth) + 256;
-
- if (futilityValue <= alpha)
- {
- bestValue = std::max(bestValue, futilityValue);
- continue;
- }
- }
+ if ( predictedDepth < 7 * ONE_PLY
+ && ss->staticEval + futility_margin(predictedDepth) + 256 <= alpha)
+ continue;
// Prune moves with negative SEE at low depths
if (predictedDepth < 4 * ONE_PLY && pos.see_sign(move) < VALUE_ZERO)
}
ss->currentMove = move;
- ss->counterMoves = &CounterMoveHistory[pos.moved_piece(move)][to_sq(move)];
+ ss->counterMoves = &CounterMoveHistory[moved_piece][to_sq(move)];
// Step 14. Make the move
pos.do_move(move, st, givesCheck);
&& !captureOrPromotion)
{
Depth r = reduction<PvNode>(improving, depth, moveCount);
- Value hValue = thisThread->history[pos.piece_on(to_sq(move))][to_sq(move)];
- Value cmhValue = cmh[pos.piece_on(to_sq(move))][to_sq(move)];
-
- const CounterMoveStats* fm = (ss - 2)->counterMoves;
- const CounterMoveStats* fm2 = (ss - 4)->counterMoves;
- Value fmValue = (fm ? (*fm)[pos.piece_on(to_sq(move))][to_sq(move)] : VALUE_ZERO);
- Value fm2Value = (fm2 ? (*fm2)[pos.piece_on(to_sq(move))][to_sq(move)] : VALUE_ZERO);
-
- // Increase reduction for cut nodes and moves with a bad history
- if ( (!PvNode && cutNode)
- || (hValue < VALUE_ZERO && cmhValue <= VALUE_ZERO))
- r += ONE_PLY;
+ Value val = thisThread->history[moved_piece][to_sq(move)]
+ + (cmh ? (*cmh )[moved_piece][to_sq(move)] : VALUE_ZERO)
+ + (fmh ? (*fmh )[moved_piece][to_sq(move)] : VALUE_ZERO)
+ + (fmh2 ? (*fmh2)[moved_piece][to_sq(move)] : VALUE_ZERO);
- // Decrease/increase reduction for moves with a good/bad history
- int rHist = (hValue + cmhValue + fmValue + fm2Value) / 20000;
- r = std::max(DEPTH_ZERO, r - rHist * ONE_PLY);
+ // Increase reduction for cut nodes
+ if (!PvNode && cutNode)
+ r += 2 * ONE_PLY;
// Decrease reduction for moves that escape a capture. Filter out
// castling moves, because they are coded as "king captures rook" and
// hence break make_move(). Also use see() instead of see_sign(),
// because the destination square is empty.
- if ( r
- && type_of(move) == NORMAL
- && type_of(pos.piece_on(to_sq(move))) != PAWN
- && pos.see(make_move(to_sq(move), from_sq(move))) < VALUE_ZERO)
- r = std::max(DEPTH_ZERO, r - ONE_PLY);
+ else if ( type_of(move) == NORMAL
+ && type_of(pos.piece_on(to_sq(move))) != PAWN
+ && pos.see(make_move(to_sq(move), from_sq(move))) < VALUE_ZERO)
+ r -= 2 * ONE_PLY;
+
+ // Decrease/increase reduction for moves with a good/bad history
+ int rHist = (val - 10000) / 20000;
+ r = std::max(DEPTH_ZERO, r - rHist * ONE_PLY);
Depth d = std::max(newDepth - r, ONE_PLY);