X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=1c000b5bad78a8d847d5f4d8c3ecfe130dff2e48;hp=fc877f3040d0923943a2a21c34f64af2a24b6bbc;hb=36a93d90f76d32e16a5f2acb09b7de2d67225021;hpb=0c1f119069bf915b85126159d4865c4bcc532239 diff --git a/src/search.cpp b/src/search.cpp index fc877f30..1c000b5b 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -39,7 +39,6 @@ namespace Search { - SignalsType Signals; LimitsType Limits; } @@ -85,7 +84,7 @@ namespace { // History and stats update bonus, based on depth int stat_bonus(Depth depth) { - int d = depth / ONE_PLY ; + int d = depth / ONE_PLY; return d > 17 ? 0 : d * d + 2 * d - 2; } @@ -154,7 +153,6 @@ namespace { void update_pv(Move* pv, Move move, Move* childPv); void update_cm_stats(Stack* ss, Piece pc, Square s, int bonus); void update_stats(const Position& pos, Stack* ss, Move move, Move* quiets, int quietsCnt, int bonus); - void check_time(); } // namespace @@ -185,7 +183,7 @@ void Search::init() { } -/// Search::clear() resets search state to zero, to obtain reproducible results +/// Search::clear() resets search state to its initial value, to obtain reproducible results void Search::clear() { @@ -193,15 +191,17 @@ void Search::clear() { for (Thread* th : Threads) { - th->counterMoves.clear(); - th->history.clear(); - th->counterMoveHistory.clear(); - th->resetCalls = true; - CounterMoveStats& cm = th->counterMoveHistory[NO_PIECE][0]; - int* t = &cm[NO_PIECE][0]; - std::fill(t, t + sizeof(cm), CounterMovePruneThreshold - 1); + th->counterMoves.fill(MOVE_NONE); + th->history.fill(0); + + for (auto& to : th->counterMoveHistory) + for (auto& h : to) + h.fill(0); + + th->counterMoveHistory[NO_PIECE][0].fill(CounterMovePruneThreshold - 1); } + Threads.main()->callsCnt = 0; Threads.main()->previousScore = VALUE_INFINITE; } @@ -242,6 +242,7 @@ void MainThread::search() { Color us = rootPos.side_to_move(); Time.init(Limits, us, rootPos.game_ply()); + TT.new_search(); int contempt = Options["Contempt"] * PawnValueEg / 100; // From centipawns DrawValue[ us] = VALUE_DRAW - Value(contempt); @@ -269,18 +270,18 @@ void MainThread::search() { Time.availableNodes += Limits.inc[us] - Threads.nodes_searched(); // When we reach the maximum depth, we can arrive here without a raise of - // Signals.stop. However, if we are pondering or in an infinite search, + // Threads.stop. However, if we are pondering or in an infinite search, // the UCI protocol states that we shouldn't print the best move before the // GUI sends a "stop" or "ponderhit" command. We therefore simply wait here - // until the GUI sends one of those commands (which also raises Signals.stop). - if (!Signals.stop && (Limits.ponder || Limits.infinite)) + // until the GUI sends one of those commands (which also raises Threads.stop). + if (!Threads.stop && (Limits.ponder || Limits.infinite)) { - Signals.stopOnPonderhit = true; - wait(Signals.stop); + Threads.stopOnPonderhit = true; + wait(Threads.stop); } // Stop the threads if not already stopped - Signals.stop = true; + Threads.stop = true; // Wait until all threads have finished for (Thread* th : Threads) @@ -332,8 +333,8 @@ void Thread::search() { MainThread* mainThread = (this == Threads.main() ? Threads.main() : nullptr); std::memset(ss-4, 0, 7 * sizeof(Stack)); - for(int i = 4; i > 0; i--) - (ss-i)->counterMoves = &this->counterMoveHistory[NO_PIECE][0]; // Use as sentinel + for (int i = 4; i > 0; i--) + (ss-i)->history = &this->counterMoveHistory[NO_PIECE][0]; // Use as sentinel bestValue = delta = alpha = -VALUE_INFINITE; beta = VALUE_INFINITE; @@ -345,7 +346,6 @@ void Thread::search() { EasyMove.clear(); mainThread->easyMovePlayed = mainThread->failedLow = false; mainThread->bestMoveChanges = 0; - TT.new_search(); } size_t multiPV = Options["MultiPV"]; @@ -360,8 +360,8 @@ void Thread::search() { // Iterative deepening loop until requested to stop or the target depth is reached while ( (rootDepth += ONE_PLY) < DEPTH_MAX - && !Signals.stop - && (!Limits.depth || Threads.main()->rootDepth / ONE_PLY <= Limits.depth)) + && !Threads.stop + && !(Limits.depth && mainThread && rootDepth / ONE_PLY > Limits.depth)) { // Distribute search depths across the threads if (idx) @@ -381,7 +381,7 @@ void Thread::search() { rm.previousScore = rm.score; // MultiPV loop. We perform a full root search for each PV line - for (PVIdx = 0; PVIdx < multiPV && !Signals.stop; ++PVIdx) + for (PVIdx = 0; PVIdx < multiPV && !Threads.stop; ++PVIdx) { // Reset aspiration window starting size if (rootDepth >= 5 * ONE_PLY) @@ -409,7 +409,7 @@ void Thread::search() { // If search has been stopped, we break immediately. Sorting and // writing PV back to TT is safe because RootMoves is still // valid, although it refers to the previous iteration. - if (Signals.stop) + if (Threads.stop) break; // When failing high/low give some update (without cluttering @@ -430,7 +430,7 @@ void Thread::search() { if (mainThread) { mainThread->failedLow = true; - Signals.stopOnPonderhit = false; + Threads.stopOnPonderhit = false; } } else if (bestValue >= beta) @@ -452,11 +452,11 @@ void Thread::search() { if (!mainThread) continue; - if (Signals.stop || PVIdx + 1 == multiPV || Time.elapsed() > 3000) + if (Threads.stop || PVIdx + 1 == multiPV || Time.elapsed() > 3000) sync_cout << UCI::pv(rootPos, rootDepth, alpha, beta) << sync_endl; } - if (!Signals.stop) + if (!Threads.stop) completedDepth = rootDepth; if (!mainThread) @@ -470,12 +470,12 @@ void Thread::search() { if ( Limits.mate && bestValue >= VALUE_MATE_IN_MAX_PLY && VALUE_MATE - bestValue <= 2 * Limits.mate) - Signals.stop = true; + Threads.stop = true; // Do we have time for the next iteration? Can we stop searching now? if (Limits.use_time_management()) { - if (!Signals.stop && !Signals.stopOnPonderhit) + if (!Threads.stop && !Threads.stopOnPonderhit) { // 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 @@ -497,9 +497,9 @@ void Thread::search() { // If we are allowed to ponder do not stop the search now but // keep pondering until the GUI sends "ponderhit" or "stop". if (Limits.ponder) - Signals.stopOnPonderhit = true; + Threads.stopOnPonderhit = true; else - Signals.stop = true; + Threads.stop = true; } } @@ -549,7 +549,7 @@ namespace { Depth extension, newDepth; Value bestValue, value, ttValue, eval; bool ttHit, inCheck, givesCheck, singularExtensionNode, improving; - bool captureOrPromotion, doFullDepthSearch, moveCountPruning, skipQuiets; + bool captureOrPromotion, doFullDepthSearch, moveCountPruning, skipQuiets, ttCapture; Piece moved_piece; int moveCount, quietCount; @@ -557,28 +557,13 @@ namespace { Thread* thisThread = pos.this_thread(); inCheck = pos.checkers(); moveCount = quietCount = ss->moveCount = 0; - ss->history = 0; + ss->statScore = 0; bestValue = -VALUE_INFINITE; ss->ply = (ss-1)->ply + 1; // Check for the available remaining time - if (thisThread->resetCalls.load(std::memory_order_relaxed)) - { - thisThread->resetCalls = false; - - // At low node count increase the checking rate to about 0.1% of nodes - // otherwise use a default value. - thisThread->callsCnt = Limits.nodes ? std::min(4096, int(Limits.nodes / 1024)) - : 4096; - } - - if (--thisThread->callsCnt <= 0) - { - for (Thread* th : Threads) - th->resetCalls = true; - - check_time(); - } + if (thisThread == Threads.main()) + static_cast(thisThread)->check_time(); // Used to send selDepth info to GUI if (PvNode && thisThread->maxPly < ss->ply) @@ -587,7 +572,7 @@ namespace { if (!rootNode) { // Step 2. Check for aborted search and immediate draw - if (Signals.stop.load(std::memory_order_relaxed) || pos.is_draw(ss->ply) || ss->ply >= MAX_PLY) + if (Threads.stop.load(std::memory_order_relaxed) || pos.is_draw(ss->ply) || ss->ply >= MAX_PLY) return ss->ply >= MAX_PLY && !inCheck ? evaluate(pos) : DrawValue[pos.side_to_move()]; @@ -606,7 +591,7 @@ namespace { assert(0 <= ss->ply && ss->ply < MAX_PLY); ss->currentMove = (ss+1)->excludedMove = bestMove = MOVE_NONE; - ss->counterMoves = &thisThread->counterMoveHistory[NO_PIECE][0]; + ss->history = &thisThread->counterMoveHistory[NO_PIECE][0]; (ss+2)->killers[0] = (ss+2)->killers[1] = MOVE_NONE; Square prevSq = to_sq((ss-1)->currentMove); @@ -666,7 +651,7 @@ namespace { if (err != TB::ProbeState::FAIL) { - thisThread->tbHits++; + thisThread->tbHits.fetch_add(1, std::memory_order_relaxed); int drawScore = TB::UseRule50 ? 1 : 0; @@ -749,7 +734,7 @@ namespace { Depth R = ((823 + 67 * depth / ONE_PLY) / 256 + std::min((eval - beta) / PawnValueMg, 3)) * ONE_PLY; ss->currentMove = MOVE_NULL; - ss->counterMoves = &thisThread->counterMoveHistory[NO_PIECE][0]; + ss->history = &thisThread->counterMoveHistory[NO_PIECE][0]; pos.do_null_move(st); Value nullValue = depth-R < ONE_PLY ? -qsearch(pos, ss+1, -beta, -beta+1) @@ -782,9 +767,7 @@ namespace { && abs(beta) < VALUE_MATE_IN_MAX_PLY) { Value rbeta = std::min(beta + 200, VALUE_INFINITE); - Depth rdepth = depth - 4 * ONE_PLY; - assert(rdepth >= ONE_PLY); assert(is_ok((ss-1)->currentMove)); MovePicker mp(pos, ttMove, rbeta - ss->staticEval); @@ -793,10 +776,11 @@ namespace { if (pos.legal(move)) { ss->currentMove = move; - ss->counterMoves = &thisThread->counterMoveHistory[pos.moved_piece(move)][to_sq(move)]; + ss->history = &thisThread->counterMoveHistory[pos.moved_piece(move)][to_sq(move)]; + assert(depth >= 5 * ONE_PLY); pos.do_move(move, st); - value = -search(pos, ss+1, -rbeta, -rbeta+1, rdepth, !cutNode, false); + value = -search(pos, ss+1, -rbeta, -rbeta+1, depth - 4 * ONE_PLY, !cutNode, false); pos.undo_move(move); if (value >= rbeta) return value; @@ -817,9 +801,9 @@ namespace { moves_loop: // When in check search starts from here - const CounterMoveStats& cmh = *(ss-1)->counterMoves; - const CounterMoveStats& fmh = *(ss-2)->counterMoves; - const CounterMoveStats& fm2 = *(ss-4)->counterMoves; + const PieceToHistory& cmh = *(ss-1)->history; + const PieceToHistory& fmh = *(ss-2)->history; + const PieceToHistory& fm2 = *(ss-4)->history; MovePicker mp(pos, ttMove, depth, ss); value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc @@ -835,6 +819,7 @@ moves_loop: // When in check search starts from here && (tte->bound() & BOUND_LOWER) && tte->depth() >= depth - 3 * ONE_PLY; skipQuiets = false; + ttCapture = false; // Step 11. Loop through moves // Loop through all pseudo-legal moves until no moves remain or a beta cutoff occurs @@ -953,9 +938,12 @@ moves_loop: // When in check search starts from here continue; } + if (move == ttMove && captureOrPromotion) + ttCapture = true; + // Update the current move (this must be done after singular extension search) ss->currentMove = move; - ss->counterMoves = &thisThread->counterMoveHistory[moved_piece][to_sq(move)]; + ss->history = &thisThread->counterMoveHistory[moved_piece][to_sq(move)]; // Step 14. Make the move pos.do_move(move, st, givesCheck); @@ -972,6 +960,10 @@ moves_loop: // When in check search starts from here r -= r ? ONE_PLY : DEPTH_ZERO; else { + // Increase reduction if ttMove is a capture + if (ttCapture) + r += ONE_PLY; + // Increase reduction for cut nodes if (cutNode) r += 2 * ONE_PLY; @@ -983,21 +975,21 @@ moves_loop: // When in check search starts from here && !pos.see_ge(make_move(to_sq(move), from_sq(move)))) r -= 2 * ONE_PLY; - ss->history = cmh[moved_piece][to_sq(move)] - + fmh[moved_piece][to_sq(move)] - + fm2[moved_piece][to_sq(move)] - + thisThread->history.get(~pos.side_to_move(), move) - - 4000; // Correction factor + ss->statScore = cmh[moved_piece][to_sq(move)] + + fmh[moved_piece][to_sq(move)] + + fm2[moved_piece][to_sq(move)] + + thisThread->history[~pos.side_to_move()][from_to(move)] + - 4000; // Correction factor // Decrease/increase reduction by comparing opponent's stat score - if (ss->history > 0 && (ss-1)->history < 0) + if (ss->statScore > 0 && (ss-1)->statScore < 0) r -= ONE_PLY; - else if (ss->history < 0 && (ss-1)->history > 0) + else if (ss->statScore < 0 && (ss-1)->statScore > 0) r += ONE_PLY; // Decrease/increase reduction for moves with a good/bad history - r = std::max(DEPTH_ZERO, (r / ONE_PLY - ss->history / 20000) * ONE_PLY); + r = std::max(DEPTH_ZERO, (r / ONE_PLY - ss->statScore / 20000) * ONE_PLY); } Depth d = std::max(newDepth - r, ONE_PLY); @@ -1039,7 +1031,7 @@ moves_loop: // When in check search starts from here // Finished searching the move. If a stop occurred, the return value of // the search cannot be trusted, and we return immediately without // updating best move, PV and TT. - if (Signals.stop.load(std::memory_order_relaxed)) + if (Threads.stop.load(std::memory_order_relaxed)) return VALUE_ZERO; if (rootNode) @@ -1100,7 +1092,7 @@ moves_loop: // When in check search starts from here // completed. But in this case bestValue is valid because we have fully // searched our subtree, and we can anyhow save the result in TT. /* - if (Signals.stop) + if (Threads.stop) return VALUE_DRAW; */ @@ -1164,6 +1156,7 @@ moves_loop: // When in check search starts from here Value bestValue, value, ttValue, futilityValue, futilityBase, oldAlpha; bool ttHit, givesCheck, evasionPrunable; Depth ttDepth; + int moveCount; if (PvNode) { @@ -1174,6 +1167,7 @@ moves_loop: // When in check search starts from here ss->currentMove = bestMove = MOVE_NONE; ss->ply = (ss-1)->ply + 1; + moveCount = 0; // Check for an instant draw or if the maximum ply has been reached if (pos.is_draw(ss->ply) || ss->ply >= MAX_PLY) @@ -1257,6 +1251,8 @@ moves_loop: // When in check search starts from here ? pos.check_squares(type_of(pos.piece_on(from_sq(move)))) & to_sq(move) : pos.gives_check(move); + moveCount++; + // Futility pruning if ( !InCheck && !givesCheck @@ -1282,7 +1278,7 @@ moves_loop: // When in check search starts from here // Detect non-capture evasions that are candidates to be pruned evasionPrunable = InCheck - && depth != DEPTH_ZERO + && (depth != DEPTH_ZERO || moveCount > 2) && bestValue > VALUE_MATED_IN_MAX_PLY && !pos.capture(move); @@ -1297,7 +1293,10 @@ moves_loop: // When in check search starts from here // Check for legality just before making the move if (!pos.legal(move)) + { + moveCount--; continue; + } ss->currentMove = move; @@ -1391,7 +1390,7 @@ moves_loop: // When in check search starts from here for (int i : {1, 2, 4}) if (is_ok((ss-i)->currentMove)) - (ss-i)->counterMoves->update(pc, s, bonus); + (ss-i)->history->update(pc, s, bonus); } @@ -1414,7 +1413,7 @@ moves_loop: // When in check search starts from here if (is_ok((ss-1)->currentMove)) { Square prevSq = to_sq((ss-1)->currentMove); - thisThread->counterMoves.update(pos.piece_on(prevSq), prevSq, move); + thisThread->counterMoves[pos.piece_on(prevSq)][prevSq]=move; } // Decrease all the other played quiet moves @@ -1459,11 +1458,19 @@ moves_loop: // When in check search starts from here return best; } +} // namespace // check_time() is used to print debug info and, more importantly, to detect // when we are out of available time and thus stop the search. - void check_time() { + void MainThread::check_time() { + + if (--callsCnt > 0) + return; + + // At low node count increase the checking rate to about 0.1% of nodes + // otherwise use a default value. + callsCnt = Limits.nodes ? std::min(4096, int(Limits.nodes / 1024)) : 4096; static TimePoint lastInfoTime = now(); @@ -1483,11 +1490,9 @@ moves_loop: // When in check search starts from here if ( (Limits.use_time_management() && elapsed > Time.maximum() - 10) || (Limits.movetime && elapsed >= Limits.movetime) || (Limits.nodes && Threads.nodes_searched() >= (uint64_t)Limits.nodes)) - Signals.stop = true; + Threads.stop = true; } -} // namespace - /// UCI::pv() formats PV information according to the UCI protocol. UCI requires /// that all (if any) unsearched PV lines are sent using a previous search score.