X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=3c34f185c35eda640b5022851eccdf65631a588a;hp=77c5b2d3b8829a42ff31e75d743f9fe282d3d919;hb=7904a7d930d4979fcd0bf13d48a6504f97f39a54;hpb=80d7556af785f57a4f90d121c57c9c2f85a2963e diff --git a/src/search.cpp b/src/search.cpp index 77c5b2d3..3c34f185 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -141,6 +141,7 @@ namespace { Value value_from_tt(Value v, int ply); void update_pv(Move* pv, Move move, Move* childPv); void update_stats(const Position& pos, Stack* ss, Move move, Depth depth, Move* quiets, int quietsCnt); + void check_time(); } // namespace @@ -174,9 +175,9 @@ void Search::init() { } -/// Search::reset() clears all search memory, to obtain reproducible search results +/// Search::clear() resets to zero search state, to obtain reproducible results -void Search::reset () { +void Search::clear() { TT.clear(); CounterMovesHistory.clear(); @@ -216,14 +217,14 @@ uint64_t Search::perft(Position& pos, Depth depth) { return nodes; } -template uint64_t Search::perft(Position& pos, Depth depth); +template uint64_t Search::perft(Position&, Depth); -/// MainThread::think() is called by the main thread when the program receives +/// MainThread::search() is called by the main thread when the program receives /// the UCI 'go' command. It searches from root position and at the end prints /// the "bestmove" to output. -void MainThread::think() { +void MainThread::search() { Color us = rootPos.side_to_move(); Time.init(Limits, us, rootPos.game_ply()); @@ -289,28 +290,15 @@ void MainThread::think() { { th->maxPly = 0; th->rootDepth = DEPTH_ZERO; - th->searching = true; if (th != this) { th->rootPos = Position(rootPos, th); th->rootMoves = rootMoves; - th->notify_one(); // Wake up the thread and start searching + th->start_searching(); } } - Threads.timer->run = true; - Threads.timer->notify_one(); // Start the recurring timer - - search(true); // Let's start searching! - - // Stop the threads and the timer - Signals.stop = true; - Threads.timer->run = false; - - // Wait until all threads have finished - for (Thread* th : Threads) - if (th != this) - th->wait_while(th->searching); + Thread::search(); // Let's start searching! } // When playing in 'nodes as time' mode, subtract the searched nodes from @@ -329,10 +317,31 @@ void MainThread::think() { wait(Signals.stop); } - sync_cout << "bestmove " << UCI::move(rootMoves[0].pv[0], rootPos.is_chess960()); + // Stop the threads if not already stopped + Signals.stop = true; - if (rootMoves[0].pv.size() > 1 || rootMoves[0].extract_ponder_from_tt(rootPos)) - std::cout << " ponder " << UCI::move(rootMoves[0].pv[1], rootPos.is_chess960()); + // Wait until all threads have finished + for (Thread* th : Threads) + if (th != this) + th->wait_for_search_finished(); + + // Check if there are threads with a better score than main thread. + Thread* bestThread = this; + if (Options["MultiPV"] == 1 && !Skill(Options["Skill Level"]).enabled()) + for (Thread* th : Threads) + if ( th->completedDepth > bestThread->completedDepth + && th->rootMoves[0].score > bestThread->rootMoves[0].score) + bestThread = th; + + // Send new PV when needed. + // FIXME: Breaks multiPV, and skill levels + if (bestThread != this) + sync_cout << UCI::pv(bestThread->rootPos, bestThread->completedDepth, -VALUE_INFINITE, VALUE_INFINITE) << sync_endl; + + sync_cout << "bestmove " << UCI::move(bestThread->rootMoves[0].pv[0], rootPos.is_chess960()); + + if (bestThread->rootMoves[0].pv.size() > 1 || bestThread->rootMoves[0].extract_ponder_from_tt(rootPos)) + std::cout << " ponder " << UCI::move(bestThread->rootMoves[0].pv[1], rootPos.is_chess960()); std::cout << sync_endl; } @@ -342,16 +351,18 @@ void MainThread::think() { // repeatedly with increasing depth until the allocated thinking time has been // consumed, user stops the search, or the maximum search depth is reached. -void Thread::search(bool isMainThread) { +void Thread::search() { - Stack* ss = stack + 2; // To allow referencing (ss-2) and (ss+2) + Stack stack[MAX_PLY+4], *ss = stack+2; // To allow referencing (ss-2) and (ss+2) Value bestValue, alpha, beta, delta; Move easyMove = MOVE_NONE; + bool isMainThread = (this == Threads.main()); std::memset(ss-2, 0, 5 * sizeof(Stack)); bestValue = delta = alpha = -VALUE_INFINITE; beta = VALUE_INFINITE; + completedDepth = DEPTH_ZERO; if (isMainThread) { @@ -376,7 +387,7 @@ void Thread::search(bool isMainThread) { { // Set up the new depth for the helper threads if (!isMainThread) - rootDepth = Threads.main()->rootDepth + Depth(int(3 * log(1 + this->idx))); + rootDepth = std::min(DEPTH_MAX - ONE_PLY, Threads.main()->rootDepth + Depth(int(2.2 * log(1 + this->idx)))); // Age out PV variability metric if (isMainThread) @@ -472,6 +483,9 @@ void Thread::search(bool isMainThread) { sync_cout << UCI::pv(rootPos, rootDepth, alpha, beta) << sync_endl; } + if (!Signals.stop) + completedDepth = rootDepth; + if (!isMainThread) continue; @@ -519,9 +533,6 @@ void Thread::search(bool isMainThread) { } } - searching = false; - notify_one(); // Wake up main thread if is sleeping waiting for us - if (!isMainThread) return; @@ -549,7 +560,7 @@ namespace { assert(-VALUE_INFINITE <= alpha && alpha < beta && beta <= VALUE_INFINITE); assert(PvNode || (alpha == beta - 1)); - assert(depth > DEPTH_ZERO); + assert(DEPTH_ZERO < depth && depth < DEPTH_MAX); Move pv[MAX_PLY+1], quietsSearched[64]; StateInfo st; @@ -569,6 +580,20 @@ namespace { bestValue = -VALUE_INFINITE; ss->ply = (ss-1)->ply + 1; + // Check for available remaining time + if (thisThread->resetCalls.load(std::memory_order_relaxed)) + { + thisThread->resetCalls = false; + thisThread->callsCnt = 0; + } + if (++thisThread->callsCnt > 4096) + { + for (Thread* th : Threads) + th->resetCalls = true; + + check_time(); + } + // Used to send selDepth info to GUI if (PvNode && thisThread->maxPly < ss->ply) thisThread->maxPly = ss->ply; @@ -577,7 +602,7 @@ namespace { { // Step 2. Check for aborted search and immediate draw if (Signals.stop.load(std::memory_order_relaxed) || pos.is_draw() || ss->ply >= MAX_PLY) - return ss->ply >= MAX_PLY && !inCheck ? evaluate(pos) + 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 @@ -836,7 +861,7 @@ moves_loop: // When in check search starts from here if (RootNode && thisThread == Threads.main()) { - Signals.firstRootMove = moveCount == 1; + Signals.firstRootMove = (moveCount == 1); if (Time.elapsed() > 3000) sync_cout << "info depth " << depth / ONE_PLY @@ -896,7 +921,8 @@ moves_loop: // When in check search starts from here continue; // History based pruning - if ( depth <= 3 * ONE_PLY + 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) continue; @@ -1095,7 +1121,7 @@ moves_loop: // When in check search starts from here && is_ok((ss - 1)->currentMove) && is_ok((ss - 2)->currentMove)) { - Value bonus = Value((depth / ONE_PLY) * (depth / ONE_PLY)); + Value bonus = Value((depth / ONE_PLY) * (depth / ONE_PLY) + depth / ONE_PLY - 1); Square prevPrevSq = to_sq((ss - 2)->currentMove); CounterMovesStats& prevCmh = CounterMovesHistory[pos.piece_on(prevPrevSq)][prevPrevSq]; prevCmh.update(pos.piece_on(prevSq), prevSq, bonus); @@ -1359,8 +1385,8 @@ moves_loop: // When in check search starts from here } - // update_stats() updates killers, history, countermove history and - // countermoves stats for a quiet best move. + // update_stats() updates killers, history, countermove and countermove + // history when a new quiet best move is found. void update_stats(const Position& pos, Stack* ss, Move move, Depth depth, Move* quiets, int quietsCnt) { @@ -1371,7 +1397,7 @@ moves_loop: // When in check search starts from here ss->killers[0] = move; } - Value bonus = Value((depth / ONE_PLY) * (depth / ONE_PLY)); + Value bonus = Value((depth / ONE_PLY) * (depth / ONE_PLY) + depth / ONE_PLY - 1); Square prevSq = to_sq((ss-1)->currentMove); CounterMovesStats& cmh = CounterMovesHistory[pos.piece_on(prevSq)][prevSq]; @@ -1394,14 +1420,14 @@ moves_loop: // When in check search starts from here cmh.update(pos.moved_piece(quiets[i]), to_sq(quiets[i]), -bonus); } - // Extra penalty for TT move in previous ply when it gets refuted + // Extra penalty for a quiet TT move in previous ply when it gets refuted if ( (ss-1)->moveCount == 1 && !pos.captured_piece_type() && is_ok((ss-2)->currentMove)) { Square prevPrevSq = to_sq((ss-2)->currentMove); CounterMovesStats& prevCmh = CounterMovesHistory[pos.piece_on(prevPrevSq)][prevPrevSq]; - prevCmh.update(pos.piece_on(prevSq), prevSq, -bonus - 2 * depth / ONE_PLY - 1); + prevCmh.update(pos.piece_on(prevSq), prevSq, -bonus - 2 * (depth + 1) / ONE_PLY); } } @@ -1411,23 +1437,23 @@ moves_loop: // When in check search starts from here Move Skill::pick_best(size_t multiPV) { - // PRNG sequence should be non-deterministic, so we seed it with the time at init const Search::RootMoveVector& rootMoves = Threads.main()->rootMoves; - static PRNG rng(now()); + static PRNG rng(now()); // PRNG sequence should be non-deterministic // RootMoves are already sorted by score in descending order - int variance = std::min(rootMoves[0].score - rootMoves[multiPV - 1].score, PawnValueMg); + Value topScore = rootMoves[0].score; + int delta = std::min(topScore - rootMoves[multiPV - 1].score, PawnValueMg); int weakness = 120 - 2 * level; int maxScore = -VALUE_INFINITE; - // Choose best move. For each move score we add two terms both dependent on + // Choose best move. For each move score we add two terms, both dependent on // weakness. One deterministic and bigger for weaker levels, and one random, // then we choose the move with the resulting highest score. for (size_t i = 0; i < multiPV; ++i) { // This is our magic formula - int push = ( weakness * int(rootMoves[0].score - rootMoves[i].score) - + variance * (rng.rand() % weakness)) / 128; + int push = ( weakness * int(topScore - rootMoves[i].score) + + delta * (rng.rand() % weakness)) / 128; if (rootMoves[i].score + push > maxScore) { @@ -1435,9 +1461,47 @@ moves_loop: // When in check search starts from here best = rootMoves[i].pv[0]; } } + return best; } + + // 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() { + + static TimePoint lastInfoTime = now(); + + int elapsed = Time.elapsed(); + TimePoint tick = Limits.startTime + elapsed; + + if (tick - lastInfoTime >= 1000) + { + lastInfoTime = tick; + dbg_print(); + } + + // An engine may not stop pondering until told so by the GUI + if (Limits.ponder) + return; + + if (Limits.use_time_management()) + { + bool stillAtFirstMove = Signals.firstRootMove.load(std::memory_order_relaxed) + && !Signals.failedLowAtRoot.load(std::memory_order_relaxed) + && elapsed > Time.available() * 3 / 4; + + if (stillAtFirstMove || elapsed > Time.maximum() - 10) + Signals.stop = true; + } + else if (Limits.movetime && elapsed >= Limits.movetime) + Signals.stop = true; + + else if (Limits.nodes && Threads.nodes_searched() >= Limits.nodes) + Signals.stop = true; + } + } // namespace @@ -1512,7 +1576,8 @@ void RootMove::insert_pv_in_tt(Position& pos) { TTEntry* tte = TT.probe(pos.key(), ttHit); if (!ttHit || tte->move() != m) // Don't overwrite correct entries - tte->save(pos.key(), VALUE_NONE, BOUND_NONE, DEPTH_NONE, m, VALUE_NONE, TT.generation()); + tte->save(pos.key(), VALUE_NONE, BOUND_NONE, DEPTH_NONE, + m, VALUE_NONE, TT.generation()); pos.do_move(m, *st++, pos.gives_check(m, CheckInfo(pos))); } @@ -1522,10 +1587,10 @@ void RootMove::insert_pv_in_tt(Position& pos) { } -/// RootMove::extract_ponder_from_tt() is called in case we have no ponder move before -/// exiting the search, for instance in case we stop the search during a fail high at -/// root. We try hard to have a ponder move to return to the GUI, otherwise in case of -/// 'ponder on' we have nothing to think on. +/// RootMove::extract_ponder_from_tt() is called in case we have no ponder move +/// before exiting the search, for instance in case we stop the search during a +/// fail high at root. We try hard to have a ponder move to return to the GUI, +/// otherwise in case of 'ponder on' we have nothing to think on. bool RootMove::extract_ponder_from_tt(Position& pos) { @@ -1547,40 +1612,3 @@ bool RootMove::extract_ponder_from_tt(Position& pos) return false; } - - -/// check_time() is called by the timer thread when the timer triggers. It 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() { - - static TimePoint lastInfoTime = now(); - int elapsed = Time.elapsed(); - - if (now() - lastInfoTime >= 1000) - { - lastInfoTime = now(); - dbg_print(); - } - - // An engine may not stop pondering until told so by the GUI - if (Limits.ponder) - return; - - if (Limits.use_time_management()) - { - bool stillAtFirstMove = Signals.firstRootMove - && !Signals.failedLowAtRoot - && elapsed > Time.available() * 3 / 4; - - if ( stillAtFirstMove - || elapsed > Time.maximum() - 2 * TimerThread::Resolution) - Signals.stop = true; - } - else if (Limits.movetime && elapsed >= Limits.movetime) - Signals.stop = true; - - else if (Limits.nodes && Threads.nodes_searched() >= Limits.nodes) - Signals.stop = true; -}