X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=6e0552be64566baac7f6e8d908520447b2ff5f38;hp=cdbf9897bd8caf88f56bb68f0557a3cf0881696b;hb=5fd5453e594ee6cadf4a3c502bc53d28cfe5aa8b;hpb=7f51610103dd5a62d9fea37c809d54e331d52de3 diff --git a/src/search.cpp b/src/search.cpp index cdbf9897..6e0552be 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -173,7 +173,7 @@ uint64_t Search::perft(Position& pos, Depth depth) { cnt = 1, nodes++; else { - pos.do_move(*it, st, ci, pos.gives_check(*it, ci)); + pos.do_move(*it, st, pos.gives_check(*it, ci)); cnt = leaf ? MoveList(pos).size() : perft(pos, depth - ONE_PLY); nodes += cnt; pos.undo_move(*it); @@ -276,7 +276,7 @@ void Search::think() { sync_cout << "bestmove " << UCI::move(RootMoves[0].pv[0], RootPos.is_chess960()); - if (RootMoves[0].pv.size() > 1) + 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()); std::cout << sync_endl; @@ -702,7 +702,7 @@ namespace { if (pos.legal(move, ci.pinned)) { ss->currentMove = move; - pos.do_move(move, st, ci, pos.gives_check(move, ci)); + pos.do_move(move, st, pos.gives_check(move, ci)); value = -search(pos, ss+1, -rbeta, -rbeta+1, rdepth, !cutNode); pos.undo_move(move); if (value >= rbeta) @@ -831,7 +831,8 @@ moves_loop: // When in check and at SpNode search starts from here newDepth = depth - ONE_PLY + extension; // Step 13. Pruning at shallow depth - if ( !captureOrPromotion + if ( !RootNode + && !captureOrPromotion && !inCheck && !dangerous && bestValue > VALUE_MATED_IN_MAX_PLY) @@ -893,7 +894,7 @@ moves_loop: // When in check and at SpNode search starts from here quietsSearched[quietCount++] = move; // Step 14. Make the move - pos.do_move(move, st, ci, givesCheck); + pos.do_move(move, st, givesCheck); // Step 15. Reduced depth search (LMR). If the move fails high it will be // re-searched at full depth. @@ -1041,7 +1042,9 @@ moves_loop: // When in check and at SpNode search starts from here && Threads.size() >= 2 && depth >= Threads.minimumSplitDepth && ( !thisThread->activeSplitPoint - || !thisThread->activeSplitPoint->allSlavesSearching) + || !thisThread->activeSplitPoint->allSlavesSearching + || ( Threads.size() > MAX_SLAVES_PER_SPLITPOINT + && thisThread->activeSplitPoint->slavesMask.count() == MAX_SLAVES_PER_SPLITPOINT)) && thisThread->splitPointsSize < MAX_SPLITPOINTS_PER_THREAD) { assert(bestValue > -VALUE_INFINITE && bestValue < beta); @@ -1254,7 +1257,7 @@ moves_loop: // When in check and at SpNode search starts from here ss->currentMove = move; // Make and search the move - pos.do_move(move, st, ci, givesCheck); + pos.do_move(move, st, givesCheck); value = givesCheck ? -qsearch(pos, ss+1, -beta, -alpha, depth - ONE_PLY) : -qsearch(pos, ss+1, -beta, -alpha, depth - ONE_PLY); pos.undo_move(move); @@ -1392,10 +1395,6 @@ moves_loop: // When in check and at SpNode search starts from here { int score = RootMoves[i].score; - // Don't allow crazy blunders even at very low skills - if (i > 0 && RootMoves[i - 1].score > score + 2 * PawnValueMg) - break; - // This is our magic formula score += ( weakness * int(RootMoves[0].score - score) + variance * (rng.rand() % weakness)) / 128; @@ -1450,8 +1449,12 @@ moves_loop: // When in check and at SpNode search starts from here ss << (v >= beta ? " lowerbound" : v <= alpha ? " upperbound" : ""); ss << " nodes " << pos.nodes_searched() - << " nps " << pos.nodes_searched() * 1000 / elapsed - << " tbhits " << TB::Hits + << " nps " << pos.nodes_searched() * 1000 / elapsed; + + if (elapsed > 1000) // Earlier makes little sense + ss << " hashfull " << TT.hashfull(); + + ss << " tbhits " << TB::Hits << " time " << elapsed << " pv"; @@ -1491,15 +1494,39 @@ 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. + +Move RootMove::extract_ponder_from_tt(Position& pos) +{ + StateInfo st; + bool found; + + assert(pv.size() == 1); + + pos.do_move(pv[0], st); + TTEntry* tte = TT.probe(pos.key(), found); + Move m = found ? tte->move() : MOVE_NONE; + if (!MoveList(pos).contains(m)) + m = MOVE_NONE; + + pos.undo_move(pv[0]); + pv.push_back(m); + return m; +} + + /// Thread::idle_loop() is where the thread is parked when it has no work to do void Thread::idle_loop() { // Pointer 'this_sp' is not null only if we are called from split(), and not // at the thread creation. This means we are the split point's master. - SplitPoint* this_sp = splitPointsSize ? activeSplitPoint : NULL; + SplitPoint* this_sp = activeSplitPoint; - assert(!this_sp || (this_sp->masterThread == this && searching)); + assert(!this_sp || (this_sp->master == this && searching)); while (!exit) { @@ -1509,6 +1536,7 @@ void Thread::idle_loop() { Threads.mutex.lock(); assert(activeSplitPoint); + SplitPoint* sp = activeSplitPoint; Threads.mutex.unlock(); @@ -1547,11 +1575,11 @@ void Thread::idle_loop() { // 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 ( this != sp->masterThread - && sp->slavesMask.none()) + if (this != sp->master && sp->slavesMask.none()) { - assert(!sp->masterThread->searching); - sp->masterThread->notify_one(); + assert(!sp->master->searching); + + sp->master->notify_one(); } // After releasing the lock we can't access any SplitPoint related data @@ -1561,37 +1589,62 @@ void Thread::idle_loop() { // Try to late join to another split point if none of its slaves has // already finished. - if (Threads.size() > 2) - for (size_t i = 0; i < Threads.size(); ++i) + SplitPoint* bestSp = NULL; + int bestScore = INT_MAX; + + for (size_t i = 0; i < Threads.size(); ++i) + { + const size_t size = Threads[i]->splitPointsSize; // Local copy + sp = size ? &Threads[i]->splitPoints[size - 1] : NULL; + + if ( sp + && sp->allSlavesSearching + && sp->slavesMask.count() < MAX_SLAVES_PER_SPLITPOINT + && available_to(Threads[i])) { - const int size = Threads[i]->splitPointsSize; // Local copy - sp = size ? &Threads[i]->splitPoints[size - 1] : NULL; + assert(this != Threads[i]); + assert(!(this_sp && this_sp->slavesMask.none())); + assert(Threads.size() > 2); + + // Prefer to join to SP with few parents to reduce the probability + // that a cut-off occurs above us, and hence we waste our work. + int level = -1; + for (SplitPoint* spp = Threads[i]->activeSplitPoint; spp; spp = spp->parentSplitPoint) + level++; - if ( sp - && sp->allSlavesSearching - && available_to(Threads[i])) + int score = level * 256 * 256 + (int)sp->slavesMask.count() * 256 - sp->depth * 1; + + if (score < bestScore) { - // Recheck the conditions under lock protection - Threads.mutex.lock(); - sp->mutex.lock(); - - if ( sp->allSlavesSearching - && available_to(Threads[i])) - { - sp->slavesMask.set(idx); - activeSplitPoint = sp; - searching = true; - } - - sp->mutex.unlock(); - Threads.mutex.unlock(); - - break; // Just a single attempt + bestSp = sp; + bestScore = score; } } + } + + if (bestSp) + { + sp = bestSp; + + // Recheck the conditions under lock protection + Threads.mutex.lock(); + sp->mutex.lock(); + + if ( sp->allSlavesSearching + && sp->slavesMask.count() < MAX_SLAVES_PER_SPLITPOINT + && available_to(sp->master)) + { + sp->slavesMask.set(idx); + activeSplitPoint = sp; + searching = true; + } + + sp->mutex.unlock(); + Threads.mutex.unlock(); + } } - // Grab the lock to avoid races with Thread::notify_one() + // Avoid races with notify_one() fired from last slave of the split point mutex.lock(); // If we are master and all slaves have finished then exit idle_loop @@ -1653,7 +1706,7 @@ void check_time() { // Loop across all split points and sum accumulated SplitPoint nodes plus // all the currently active positions nodes. for (size_t i = 0; i < Threads.size(); ++i) - for (int j = 0; j < Threads[i]->splitPointsSize; ++j) + for (size_t j = 0; j < Threads[i]->splitPointsSize; ++j) { SplitPoint& sp = Threads[i]->splitPoints[j];