X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=38d5683493a5b14df76a7196a340b49a8b429ebd;hp=2678f7d5d9bae66685e3a108ec1868bdfde5d014;hb=6ab92d2e1c417fa7a9fd87eee0add2bf02112296;hpb=4a0db9ea3c34d7663a039c40ce810ba9cb743cca diff --git a/src/search.cpp b/src/search.cpp index 2678f7d5..38d56834 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -2,7 +2,7 @@ Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad - Copyright (C) 2015-2018 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad + Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, 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 @@ -85,10 +85,10 @@ namespace { return d > 17 ? 0 : 29 * d * d + 138 * d - 134; } - // Add a small random component to draw evaluations to keep search dynamic + // Add a small random component to draw evaluations to keep search dynamic // and to avoid 3fold-blindness. Value value_draw(Depth depth, Thread* thisThread) { - return depth < 4 ? VALUE_DRAW + return depth < 4 ? VALUE_DRAW : VALUE_DRAW + Value(2 * (thisThread->nodes.load(std::memory_order_relaxed) % 2) - 1); } @@ -187,6 +187,7 @@ void Search::clear() { Time.availableNodes = 0; TT.clear(); Threads.clear(); + Tablebases::init(Options["SyzygyPath"]); // Free up mapped files } @@ -368,7 +369,6 @@ void Thread::search() { size_t pvFirst = 0; pvLast = 0; - Depth adjustedDepth = rootDepth; // MultiPV loop. We perform a full root search for each PV line for (pvIdx = 0; pvIdx < multiPV && !Threads.stop; ++pvIdx) @@ -405,7 +405,7 @@ void Thread::search() { int failedHighCnt = 0; while (true) { - adjustedDepth = std::max(ONE_PLY, rootDepth - failedHighCnt * ONE_PLY); + Depth adjustedDepth = std::max(ONE_PLY, rootDepth - failedHighCnt * ONE_PLY); bestValue = ::search(rootPos, ss, alpha, beta, adjustedDepth, false); // Bring the best move to the front. It is critical that sorting @@ -428,7 +428,7 @@ void Thread::search() { && multiPV == 1 && (bestValue <= alpha || bestValue >= beta) && Time.elapsed() > 3000) - sync_cout << UCI::pv(rootPos, adjustedDepth, alpha, beta) << sync_endl; + sync_cout << UCI::pv(rootPos, rootDepth, alpha, beta) << sync_endl; // In case of failing low/high increase aspiration window and // re-search, otherwise exit the loop. @@ -463,15 +463,15 @@ void Thread::search() { if ( mainThread && (Threads.stop || pvIdx + 1 == multiPV || Time.elapsed() > 3000)) - sync_cout << UCI::pv(rootPos, adjustedDepth, alpha, beta) << sync_endl; + sync_cout << UCI::pv(rootPos, rootDepth, alpha, beta) << sync_endl; } if (!Threads.stop) - completedDepth = adjustedDepth; + completedDepth = rootDepth; if (rootMoves[0].pv[0] != lastBestMove) { lastBestMove = rootMoves[0].pv[0]; - lastBestMoveDepth = adjustedDepth; + lastBestMoveDepth = rootDepth; } // Have we found a "mate in x"? @@ -599,7 +599,7 @@ namespace { 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) + return (ss->ply >= MAX_PLY && !inCheck) ? evaluate(pos) : value_draw(depth, pos.this_thread()); // Step 3. Mate distance pruning. Even if we mate at the next move our score @@ -683,6 +683,10 @@ namespace { TB::ProbeState err; TB::WDLScore wdl = Tablebases::probe_wdl(pos, &err); + // Force check of time on the next occasion + if (thisThread == Threads.main()) + static_cast(thisThread)->callsCnt = 0; + if (err != TB::ProbeState::FAIL) { thisThread->tbHits.fetch_add(1, std::memory_order_relaxed); @@ -944,6 +948,10 @@ moves_loop: // When in check, search starts from here && pos.see_ge(move)) extension = ONE_PLY; + else if ( pos.can_castle(us) // Extension for king moves that change castling rights + && type_of(movedPiece) == KING) + extension = ONE_PLY; + // Calculate new depth for this move newDepth = depth - ONE_PLY + extension; @@ -1387,21 +1395,15 @@ moves_loop: // When in check, search starts from here if (value > alpha) { + bestMove = move; + if (PvNode) // Update pv even in fail-high case update_pv(ss->pv, move, (ss+1)->pv); if (PvNode && value < beta) // Update alpha here! - { alpha = value; - bestMove = move; - } - else // Fail high - { - tte->save(posKey, value_to_tt(value, ss->ply), BOUND_LOWER, - ttDepth, move, ss->staticEval); - - return value; - } + else + break; // Fail high } } } @@ -1412,7 +1414,8 @@ moves_loop: // When in check, search starts from here return mated_in(ss->ply); // Plies to mate from the root tte->save(posKey, value_to_tt(bestValue, ss->ply), - PvNode && bestValue > oldAlpha ? BOUND_EXACT : BOUND_UPPER, + bestValue >= beta ? BOUND_LOWER : + PvNode && bestValue > oldAlpha ? BOUND_EXACT : BOUND_UPPER, ttDepth, bestMove, ss->staticEval); assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);