/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
return (Depth) Reductions[PvNode][i][std::min(int(d) / ONE_PLY, 63)][std::min(mn, 63)];
}
- size_t PVSize, PVIdx;
+ size_t MultiPV, PVIdx;
TimeManager TimeMgr;
double BestMoveChanges;
Value DrawValue[COLOR_NB];
HistoryStats History;
GainsStats Gains;
- CountermovesStats Countermoves;
+ MovesStats Countermoves, Followupmoves;
template <NodeType NT>
Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth, bool cutNode);
void id_loop(Position& pos);
Value value_to_tt(Value v, int ply);
Value value_from_tt(Value v, int ply);
- bool allows(const Position& pos, Move first, Move second);
- bool refutes(const Position& pos, Move first, Move second);
+ void update_stats(Position& pos, Stack* ss, Move move, Depth depth, Move* quiets, int quietsCnt);
string uci_pv(const Position& pos, int depth, Value alpha, Value beta);
struct Skill {
// Init reductions array
for (hd = 1; hd < 64; ++hd) for (mc = 1; mc < 64; ++mc)
{
- double pvRed = log(double(hd)) * log(double(mc)) / 3.0;
+ double pvRed = 0.00 + log(double(hd)) * log(double(mc)) / 3.00;
double nonPVRed = 0.33 + log(double(hd)) * log(double(mc)) / 2.25;
Reductions[1][1][hd][mc] = (int8_t) ( pvRed >= 1.0 ? floor( pvRed * int(ONE_PLY)) : 0);
Reductions[0][1][hd][mc] = (int8_t) (nonPVRed >= 1.0 ? floor(nonPVRed * int(ONE_PLY)) : 0);
// Init futility move count array
for (d = 0; d < 32; ++d)
{
- FutilityMoveCounts[0][d] = int(2.4 + 0.222 * pow(d + 0.0, 1.8));
- FutilityMoveCounts[1][d] = int(3.0 + 0.3 * pow(d + 0.98, 1.8));
+ FutilityMoveCounts[0][d] = int(2.4 + 0.222 * pow(d + 0.00, 1.8));
+ FutilityMoveCounts[1][d] = int(3.0 + 0.300 * pow(d + 0.98, 1.8));
}
}
/// Search::perft() is our utility to verify move generation. All the leaf nodes
/// up to the given depth are generated and counted and the sum returned.
-static size_t perft(Position& pos, Depth depth) {
+static uint64_t perft(Position& pos, Depth depth) {
StateInfo st;
- size_t cnt = 0;
+ uint64_t cnt = 0;
CheckInfo ci(pos);
const bool leaf = depth == 2 * ONE_PLY;
return cnt;
}
-size_t Search::perft(Position& pos, Depth depth) {
+uint64_t Search::perft(Position& pos, Depth depth) {
return depth > ONE_PLY ? ::perft(pos, depth) : MoveList<LEGAL>(pos).size();
}
RootColor = RootPos.side_to_move();
TimeMgr.init(Limits, RootPos.game_ply(), RootColor);
+ int cf = Options["Contempt Factor"] * PawnValueMg / 100; // From centipawns
+ DrawValue[ RootColor] = VALUE_DRAW - Value(cf);
+ DrawValue[~RootColor] = VALUE_DRAW + Value(cf);
+
if (RootMoves.empty())
{
RootMoves.push_back(MOVE_NONE);
}
}
- if (Options["Contempt Factor"] && !Options["UCI_AnalyseMode"])
- {
- int cf = Options["Contempt Factor"] * PawnValueMg / 100; // From centipawns
- cf = cf * Material::game_phase(RootPos) / PHASE_MIDGAME; // Scale down with phase
- DrawValue[ RootColor] = VALUE_DRAW - Value(cf);
- DrawValue[~RootColor] = VALUE_DRAW + Value(cf);
- }
- else
- DrawValue[WHITE] = DrawValue[BLACK] = VALUE_DRAW;
-
if (Options["Write Search Log"])
{
Log log(Options["Search Log Filename"]);
History.clear();
Gains.clear();
Countermoves.clear();
+ Followupmoves.clear();
- PVSize = Options["MultiPV"];
+ MultiPV = Options["MultiPV"];
Skill skill(Options["Skill Level"]);
// Do we have to play with skill handicap? In this case enable MultiPV search
// that we will use behind the scenes to retrieve a set of possible moves.
- if (skill.enabled() && PVSize < 4)
- PVSize = 4;
+ if (skill.enabled() && MultiPV < 4)
+ MultiPV = 4;
- PVSize = std::min(PVSize, RootMoves.size());
+ MultiPV = std::min(MultiPV, RootMoves.size());
// Iterative deepening loop until requested to stop or target depth reached
while (++depth <= MAX_PLY && !Signals.stop && (!Limits.depth || depth <= Limits.depth))
{
// Age out PV variability metric
- BestMoveChanges *= 0.8;
+ BestMoveChanges *= 0.5;
// Save the last iteration's scores before first PV line is searched and
// all the move scores except the (new) PV are set to -VALUE_INFINITE.
RootMoves[i].prevScore = RootMoves[i].score;
// MultiPV loop. We perform a full root search for each PV line
- for (PVIdx = 0; PVIdx < PVSize && !Signals.stop; ++PVIdx)
+ for (PVIdx = 0; PVIdx < MultiPV && !Signals.stop; ++PVIdx)
{
// Reset aspiration window starting size
if (depth >= 5)
// Sort the PV lines searched so far and update the GUI
std::stable_sort(RootMoves.begin(), RootMoves.begin() + PVIdx + 1);
- if (PVIdx + 1 == PVSize || Time::now() - SearchTime > 3000)
+ if (PVIdx + 1 == MultiPV || Time::now() - SearchTime > 3000)
sync_cout << uci_pv(pos, depth, alpha, beta) << sync_endl;
}
// Do we have time for the next iteration? Can we stop searching now?
if (Limits.use_time_management() && !Signals.stop && !Signals.stopOnPonderhit)
{
- bool stop = false; // Local variable, not the volatile Signals.stop
-
// Take some extra time if the best move has changed
- if (depth > 4 && depth < 50 && PVSize == 1)
+ if (depth > 4 && depth < 50 && MultiPV == 1)
TimeMgr.pv_instability(BestMoveChanges);
- // Stop the search if most of the available time has been used. We
- // probably don't have enough time to search the first move at the
- // next iteration anyway.
- if (Time::now() - SearchTime > (TimeMgr.available_time() * 62) / 100)
- stop = true;
-
- // Stop the search early if one move seems to be much better than others
- if ( depth >= 12
- && BestMoveChanges <= DBL_EPSILON
- && !stop
- && PVSize == 1
- && bestValue > VALUE_MATED_IN_MAX_PLY
- && ( RootMoves.size() == 1
- || Time::now() - SearchTime > (TimeMgr.available_time() * 20) / 100))
- {
- Value rBeta = bestValue - 2 * PawnValueMg;
- ss->excludedMove = RootMoves[0].pv[0];
- ss->skipNullMove = true;
- Value v = search<NonPV>(pos, ss, rBeta - 1, rBeta, (depth - 3) * ONE_PLY, true);
- ss->skipNullMove = false;
- ss->excludedMove = MOVE_NONE;
-
- if (v < rBeta)
- stop = true;
- }
-
- if (stop)
+ // Stop the search if only one legal move is available or all
+ // of the available time has been used.
+ if ( RootMoves.size() == 1
+ || Time::now() - SearchTime > TimeMgr.available_time())
{
// If we are allowed to ponder do not stop the search now but
// keep pondering until the GUI sends "ponderhit" or "stop".
const bool SpNode = (NT == SplitPointPV || NT == SplitPointNonPV || NT == SplitPointRoot);
const bool RootNode = (NT == Root || NT == SplitPointRoot);
- assert(alpha >= -VALUE_INFINITE && alpha < beta && beta <= VALUE_INFINITE);
+ assert(-VALUE_INFINITE <= alpha && alpha < beta && beta <= VALUE_INFINITE);
assert(PvNode || (alpha == beta - 1));
assert(depth > DEPTH_ZERO);
const TTEntry *tte;
SplitPoint* splitPoint;
Key posKey;
- Move ttMove, move, excludedMove, bestMove, threatMove;
+ Move ttMove, move, excludedMove, bestMove;
Depth ext, newDepth, predictedDepth;
Value bestValue, value, ttValue, eval, nullValue, futilityValue;
bool inCheck, givesCheck, pvMove, singularExtensionNode, improving;
{
splitPoint = ss->splitPoint;
bestMove = splitPoint->bestMove;
- threatMove = splitPoint->threatMove;
bestValue = splitPoint->bestValue;
tte = NULL;
ttMove = excludedMove = MOVE_NONE;
moveCount = quietCount = 0;
bestValue = -VALUE_INFINITE;
- ss->currentMove = threatMove = (ss+1)->excludedMove = bestMove = MOVE_NONE;
+ ss->currentMove = ss->ttMove = (ss+1)->excludedMove = bestMove = MOVE_NONE;
ss->ply = (ss-1)->ply + 1;
(ss+1)->skipNullMove = false; (ss+1)->reduction = DEPTH_ZERO;
(ss+2)->killers[0] = (ss+2)->killers[1] = MOVE_NONE;
{
// Step 2. Check for aborted search and immediate draw
if (Signals.stop || pos.is_draw() || ss->ply > MAX_PLY)
- return DrawValue[pos.side_to_move()];
+ return ss->ply > MAX_PLY && !inCheck ? evaluate(pos) : DrawValue[pos.side_to_move()];
// Step 3. Mate distance pruning. Even if we mate at the next move our score
// would be at best mate_in(ss->ply+1), but if alpha is already bigger because
excludedMove = ss->excludedMove;
posKey = excludedMove ? pos.exclusion_key() : pos.key();
tte = TT.probe(posKey);
- ttMove = RootNode ? RootMoves[PVIdx].pv[0] : tte ? tte->move() : MOVE_NONE;
+ ss->ttMove = ttMove = RootNode ? RootMoves[PVIdx].pv[0] : tte ? tte->move() : MOVE_NONE;
ttValue = tte ? value_from_tt(tte->value(), ss->ply) : VALUE_NONE;
// At PV nodes we check for exact scores, whilst at non-PV nodes we check for
: ttValue >= beta ? (tte->bound() & BOUND_LOWER)
: (tte->bound() & BOUND_UPPER)))
{
- TT.refresh(tte);
ss->currentMove = ttMove; // Can be MOVE_NONE
- if ( ttValue >= beta
- && ttMove
- && !pos.capture_or_promotion(ttMove)
- && ttMove != ss->killers[0])
- {
- ss->killers[1] = ss->killers[0];
- ss->killers[0] = ttMove;
- }
+ // If ttMove is quiet, update killers, history, counter move and followup move on TT hit
+ if (ttValue >= beta && ttMove && !pos.capture_or_promotion(ttMove) && !inCheck)
+ update_stats(pos, ss, ttMove, depth, NULL, 0);
+
return ttValue;
}
// Step 6. Razoring (skipped when in check)
if ( !PvNode
&& depth < 4 * ONE_PLY
- && eval + razor_margin(depth) < beta
+ && eval + razor_margin(depth) <= alpha
&& ttMove == MOVE_NONE
&& abs(beta) < VALUE_MATE_IN_MAX_PLY
&& !pos.pawn_on_7th(pos.side_to_move()))
{
- Value rbeta = beta - razor_margin(depth);
- Value v = qsearch<NonPV, false>(pos, ss, rbeta-1, rbeta, DEPTH_ZERO);
- if (v < rbeta)
- // Logically we should return (v + razor_margin(depth)), but
- // surprisingly this performed slightly weaker in tests.
+ Value ralpha = alpha - razor_margin(depth);
+ Value v = qsearch<NonPV, false>(pos, ss, ralpha, ralpha+1, DEPTH_ZERO);
+ if (v <= ralpha)
return v;
}
{
ss->currentMove = MOVE_NULL;
- // Null move dynamic reduction based on depth
- Depth R = 3 * ONE_PLY + depth / 4;
+ assert(eval - beta >= 0);
- // Null move dynamic reduction based on value
- if (eval - PawnValueMg > beta)
- R += ONE_PLY;
+ // Null move dynamic reduction based on depth and value
+ Depth R = 3 * ONE_PLY
+ + depth / 4
+ + int(eval - beta) / PawnValueMg * ONE_PLY;
pos.do_null_move(st);
(ss+1)->skipNullMove = true;
- nullValue = depth-R < ONE_PLY ? -qsearch<NonPV, false>(pos, ss+1, -beta, -alpha, DEPTH_ZERO)
- : - search<NonPV>(pos, ss+1, -beta, -alpha, depth-R, !cutNode);
+ nullValue = depth-R < ONE_PLY ? -qsearch<NonPV, false>(pos, ss+1, -beta, -beta+1, DEPTH_ZERO)
+ : - search<NonPV>(pos, ss+1, -beta, -beta+1, depth-R, !cutNode);
(ss+1)->skipNullMove = false;
pos.undo_null_move();
// Do verification search at high depths
ss->skipNullMove = true;
- Value v = search<NonPV>(pos, ss, alpha, beta, depth-R, false);
+ Value v = depth-R < ONE_PLY ? qsearch<NonPV, false>(pos, ss, beta-1, beta, DEPTH_ZERO)
+ : search<NonPV>(pos, ss, beta-1, beta, depth-R, false);
ss->skipNullMove = false;
if (v >= beta)
return nullValue;
}
- else
- {
- // The null move failed low, which means that we may be faced with
- // some kind of threat. If the previous move was reduced, check if
- // the move that refuted the null move was somehow connected to the
- // move which was reduced. If a connection is found, return a fail
- // low score (which will cause the reduced move to fail high in the
- // parent node, which will trigger a re-search with full depth).
- threatMove = (ss+1)->currentMove;
-
- if ( depth < 5 * ONE_PLY
- && (ss-1)->reduction
- && threatMove != MOVE_NONE
- && allows(pos, (ss-1)->currentMove, threatMove))
- return alpha;
- }
}
// Step 9. ProbCut (skipped when in check)
&& !ss->skipNullMove
&& abs(beta) < VALUE_MATE_IN_MAX_PLY)
{
- Value rbeta = beta + 200;
- Depth rdepth = depth - ONE_PLY - 3 * ONE_PLY;
+ Value rbeta = std::min(beta + 200, VALUE_INFINITE);
+ Depth rdepth = depth - 4 * ONE_PLY;
assert(rdepth >= ONE_PLY);
assert((ss-1)->currentMove != MOVE_NONE);
}
// Step 10. Internal iterative deepening (skipped when in check)
- if ( depth >= (PvNode ? 5 * ONE_PLY : 8 * ONE_PLY)
- && ttMove == MOVE_NONE
+ if ( depth >= (PvNode ? 5 * ONE_PLY : 8 * ONE_PLY)
+ && !ttMove
&& (PvNode || ss->staticEval + Value(256) >= beta))
{
Depth d = depth - 2 * ONE_PLY - (PvNode ? DEPTH_ZERO : depth / 4);
Move countermoves[] = { Countermoves[pos.piece_on(prevMoveSq)][prevMoveSq].first,
Countermoves[pos.piece_on(prevMoveSq)][prevMoveSq].second };
- MovePicker mp(pos, ttMove, depth, History, countermoves, ss);
+ Square prevOwnMoveSq = to_sq((ss-2)->currentMove);
+ Move followupmoves[] = { Followupmoves[pos.piece_on(prevOwnMoveSq)][prevOwnMoveSq].first,
+ Followupmoves[pos.piece_on(prevOwnMoveSq)][prevOwnMoveSq].second };
+
+ MovePicker mp(pos, ttMove, depth, History, countermoves, followupmoves, ss);
CheckInfo ci(pos);
value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc
improving = ss->staticEval >= (ss-2)->staticEval
ext = DEPTH_ZERO;
captureOrPromotion = pos.capture_or_promotion(move);
- givesCheck = pos.gives_check(move, ci);
+
+ givesCheck = type_of(move) == NORMAL && !ci.dcCandidates
+ ? ci.checkSq[type_of(pos.piece_on(from_sq(move)))] & to_sq(move)
+ : pos.gives_check(move, ci);
+
dangerous = givesCheck
|| type_of(move) != NORMAL
|| pos.advanced_pawn_push(move);
// Step 12. Extend checks
- if (givesCheck && pos.see_sign(move) >= 0)
+ if (givesCheck && pos.see_sign(move) >= VALUE_ZERO)
ext = ONE_PLY;
// Singular extension search. If all moves but one fail low on a search of
{
// Move count based pruning
if ( depth < 16 * ONE_PLY
- && moveCount >= FutilityMoveCounts[improving][depth]
- && (!threatMove || !refutes(pos, move, threatMove)))
+ && moveCount >= FutilityMoveCounts[improving][depth] )
{
if (SpNode)
splitPoint->mutex.lock();
}
// Prune moves with negative SEE at low depths
- if (predictedDepth < 4 * ONE_PLY && pos.see_sign(move) < 0)
+ if (predictedDepth < 4 * ONE_PLY && pos.see_sign(move) < VALUE_ZERO)
{
if (SpNode)
splitPoint->mutex.lock();
value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, d, true);
+ // Research at intermediate depth if reduction is very high
+ if (value > alpha && ss->reduction >= 4 * ONE_PLY)
+ {
+ Depth d2 = std::max(newDepth - 2 * ONE_PLY, ONE_PLY);
+ value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, d2, true);
+ }
+
doFullDepthSearch = (value > alpha && ss->reduction != DEPTH_ZERO);
ss->reduction = DEPTH_ZERO;
}
assert(bestValue < beta);
thisThread->split<FakeSplit>(pos, ss, alpha, beta, &bestValue, &bestMove,
- depth, threatMove, moveCount, &mp, NT, cutNode);
+ depth, moveCount, &mp, NT, cutNode);
if (bestValue >= beta)
break;
}
// case of Signals.stop or thread.cutoff_occurred() are set, but this is
// harmless because return value is discarded anyhow in the parent nodes.
// If we are in a singular extension search then return a fail low score.
- // A split node has at least one move - the one tried before to be splitted.
+ // A split node has at least one move - the one tried before to be split.
if (!moveCount)
return excludedMove ? alpha
: inCheck ? mated_in(ss->ply) : DrawValue[pos.side_to_move()];
PvNode && bestMove ? BOUND_EXACT : BOUND_UPPER,
depth, bestMove, ss->staticEval);
- // Quiet best move: update killers, history and countermoves
- if ( bestValue >= beta
- && !pos.capture_or_promotion(bestMove)
- && !inCheck)
- {
- if (ss->killers[0] != bestMove)
- {
- ss->killers[1] = ss->killers[0];
- ss->killers[0] = bestMove;
- }
-
- // Increase history value of the cut-off move and decrease all the other
- // played non-capture moves.
- Value bonus = Value(int(depth) * int(depth));
- History.update(pos.moved_piece(bestMove), to_sq(bestMove), bonus);
- for (int i = 0; i < quietCount - 1; ++i)
- {
- Move m = quietsSearched[i];
- History.update(pos.moved_piece(m), to_sq(m), -bonus);
- }
-
- if (is_ok((ss-1)->currentMove))
- Countermoves.update(pos.piece_on(prevMoveSq), prevMoveSq, bestMove);
- }
+ // Quiet best move: update killers, history, countermoves and followupmoves
+ if (bestValue >= beta && !pos.capture_or_promotion(bestMove) && !inCheck)
+ update_stats(pos, ss, bestMove, depth, quietsSearched, quietCount - 1);
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
// Check for an instant draw or if the maximum ply has been reached
if (pos.is_draw() || ss->ply > MAX_PLY)
- return DrawValue[pos.side_to_move()];
+ return ss->ply > MAX_PLY && !InCheck ? evaluate(pos) : 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
{
assert(is_ok(move));
- givesCheck = pos.gives_check(move, ci);
+ givesCheck = type_of(move) == NORMAL && !ci.dcCandidates
+ ? ci.checkSq[type_of(pos.piece_on(from_sq(move)))] & to_sq(move)
+ : pos.gives_check(move, ci);
// Futility pruning
if ( !PvNode
continue;
}
- // Prune moves with negative or equal SEE and also moves with positive
- // SEE where capturing piece loses a tempo and SEE < beta - futilityBase.
- if ( futilityBase < beta
- && pos.see(move, beta - futilityBase) <= 0)
+ if (futilityBase < beta && pos.see(move) <= VALUE_ZERO)
{
bestValue = std::max(bestValue, futilityBase);
continue;
&& (!InCheck || evasionPrunable)
&& move != ttMove
&& type_of(move) != PROMOTION
- && pos.see_sign(move) < 0)
+ && pos.see_sign(move) < VALUE_ZERO)
continue;
// Check for legality just before making the move
}
- // allows() tests whether the 'first' move at previous ply somehow makes the
- // 'second' move possible e.g. if the moving piece is the same in both moves.
- // Normally the second move is the threat (the best move returned from a null
- // search that fails low).
-
- bool allows(const Position& pos, Move first, Move second) {
-
- assert(is_ok(first));
- assert(is_ok(second));
- assert(color_of(pos.piece_on(from_sq(second))) == ~pos.side_to_move());
- assert(type_of(first) == CASTLING || color_of(pos.piece_on(to_sq(first))) == ~pos.side_to_move());
-
- Square m1from = from_sq(first);
- Square m2from = from_sq(second);
- Square m1to = to_sq(first);
- Square m2to = to_sq(second);
-
- // The piece is the same or second's destination was vacated by the first move.
- // We exclude the trivial case where a sliding piece does in two moves what
- // it could do in one move: eg. Ra1a2, Ra2a3.
- if ( m2to == m1from
- || (m1to == m2from && !aligned(m1from, m2from, m2to)))
- return true;
+ // update_stats() updates killers, history, countermoves and followupmoves stats after a fail-high
+ // of a quiet move.
- // Second one moves through the square vacated by first one
- if (between_bb(m2from, m2to) & m1from)
- return true;
+ void update_stats(Position& pos, Stack* ss, Move move, Depth depth, Move* quiets, int quietsCnt) {
- // Second's destination is defended by the first move's piece
- Bitboard m1att = attacks_bb(pos.piece_on(m1to), m1to, pos.pieces() ^ m2from);
- if (m1att & m2to)
- return true;
-
- // Second move gives a discovered check through the first's checking piece
- if (m1att & pos.king_square(pos.side_to_move()))
+ if (ss->killers[0] != move)
{
- assert(between_bb(m1to, pos.king_square(pos.side_to_move())) & m2from);
- return true;
+ ss->killers[1] = ss->killers[0];
+ ss->killers[0] = move;
}
- return false;
- }
-
-
- // refutes() tests whether a 'first' move is able to defend against a 'second'
- // opponent's move. In this case will not be pruned. Normally the second move
- // is the threat (the best move returned from a null search that fails low).
-
- bool refutes(const Position& pos, Move first, Move second) {
-
- assert(is_ok(first));
- assert(is_ok(second));
-
- Square m1from = from_sq(first);
- Square m2from = from_sq(second);
- Square m1to = to_sq(first);
- Square m2to = to_sq(second);
-
- // Don't prune moves of the threatened piece
- if (m1from == m2to)
- return true;
-
- // If the threatened piece has a value less than or equal to the value of
- // the threat piece, don't prune moves which defend it.
- if ( pos.capture(second)
- && ( PieceValue[MG][pos.piece_on(m2from)] >= PieceValue[MG][pos.piece_on(m2to)]
- || type_of(pos.piece_on(m2from)) == KING))
+ // Increase history value of the cut-off move and decrease all the other
+ // played quiet moves.
+ Value bonus = Value(int(depth) * int(depth));
+ History.update(pos.moved_piece(move), to_sq(move), bonus);
+ for (int i = 0; i < quietsCnt; ++i)
{
- // Update occupancy as if the piece and the threat are moving
- Bitboard occ = pos.pieces() ^ m1from ^ m1to ^ m2from;
- Piece pc = pos.piece_on(m1from);
-
- // Does the moved piece attack the square 'm2to' ?
- if (attacks_bb(pc, m1to, occ) & m2to)
- return true;
-
- // Scan for possible X-ray attackers behind the moved piece
- Bitboard xray = (attacks_bb< ROOK>(m2to, occ) & pos.pieces(color_of(pc), QUEEN, ROOK))
- | (attacks_bb<BISHOP>(m2to, occ) & pos.pieces(color_of(pc), QUEEN, BISHOP));
-
- // Verify attackers are triggered by our move and not already existing
- if (unlikely(xray) && (xray & ~pos.attacks_from<QUEEN>(m2to)))
- return true;
+ Move m = quiets[i];
+ History.update(pos.moved_piece(m), to_sq(m), -bonus);
}
- // Don't prune safe moves which block the threat path
- if ((between_bb(m2from, m2to) & m1to) && pos.see_sign(first) >= 0)
- return true;
+ if (is_ok((ss-1)->currentMove))
+ {
+ Square prevMoveSq = to_sq((ss-1)->currentMove);
+ Countermoves.update(pos.piece_on(prevMoveSq), prevMoveSq, move);
+ }
- return false;
+ if (is_ok((ss-2)->currentMove) && (ss-1)->currentMove == (ss-1)->ttMove)
+ {
+ Square prevOwnMoveSq = to_sq((ss-2)->currentMove);
+ Followupmoves.update(pos.piece_on(prevOwnMoveSq), prevOwnMoveSq, move);
+ }
}
rk.rand<unsigned>();
// RootMoves are already sorted by score in descending order
- int variance = std::min(RootMoves[0].score - RootMoves[PVSize - 1].score, PawnValueMg);
+ int variance = std::min(RootMoves[0].score - RootMoves[MultiPV - 1].score, PawnValueMg);
int weakness = 120 - 2 * level;
int max_s = -VALUE_INFINITE;
best = MOVE_NONE;
// Choose best move. For each move score we add two terms both dependent on
// weakness. One deterministic and bigger for weaker moves, and one random,
// then we choose the move with the resulting highest score.
- for (size_t i = 0; i < PVSize; ++i)
+ for (size_t i = 0; i < MultiPV; ++i)
{
int s = RootMoves[i].score;
mutex.lock();
// If we are master and all slaves have finished then exit idle_loop
- if (this_sp && !this_sp->slavesMask)
+ if (this_sp && this_sp->slavesMask.none())
{
mutex.unlock();
break;
searching = false;
activePosition = NULL;
- sp->slavesMask &= ~(1ULL << idx);
+ sp->slavesMask.reset(idx);
sp->nodes += pos.nodes_searched();
// Wake up the master thread so to allow it to return from the idle
// loop in case we are the last slave of the split point.
if ( Threads.sleepWhileIdle
&& this != sp->masterThread
- && !sp->slavesMask)
+ && sp->slavesMask.none())
{
assert(!sp->masterThread->searching);
sp->masterThread->notify_one();
// If this thread is the master of a split point and all slaves have finished
// their work at this split point, return from the idle loop.
- if (this_sp && !this_sp->slavesMask)
+ if (this_sp && this_sp->slavesMask.none())
{
this_sp->mutex.lock();
- bool finished = !this_sp->slavesMask; // Retest under lock protection
+ bool finished = this_sp->slavesMask.none(); // Retest under lock protection
this_sp->mutex.unlock();
if (finished)
return;
sp.mutex.lock();
nodes += sp.nodes;
- Bitboard sm = sp.slavesMask;
- while (sm)
- {
- Position* pos = Threads[pop_lsb(&sm)]->activePosition;
- if (pos)
- nodes += pos->nodes_searched();
- }
+
+ for (size_t idx = 0; idx < Threads.size(); ++idx)
+ if (sp.slavesMask.test(idx) && Threads[idx]->activePosition)
+ nodes += Threads[idx]->activePosition->nodes_searched();
sp.mutex.unlock();
}
Time::point elapsed = Time::now() - SearchTime;
bool stillAtFirstMove = Signals.firstRootMove
&& !Signals.failedLowAtRoot
- && elapsed > TimeMgr.available_time();
+ && elapsed > TimeMgr.available_time() * 75 / 100;
bool noMoreTime = elapsed > TimeMgr.maximum_time() - 2 * TimerThread::Resolution
|| stillAtFirstMove;
projects / stockfish / blobdiff