X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=1e133447d381b547f97d9ea93ab7aa7321d862f7;hp=a3d4a329a1f7c4075f68e7e5261104d679cbbffc;hb=16566a8fcf76b9b72b6e746f318f77045df90017;hpb=bb5589b829b79d7c60a820d4b1634dccbc4bbb3f diff --git a/src/search.cpp b/src/search.cpp index a3d4a329..1e133447 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -61,8 +61,8 @@ namespace { // Different node types, used as a template parameter enum NodeType { NonPV, PV }; - constexpr uint64_t ttHitAverageWindow = 4096; - constexpr uint64_t ttHitAverageResolution = 1024; + constexpr uint64_t TtHitAverageWindow = 4096; + constexpr uint64_t TtHitAverageResolution = 1024; // Razor and futility margins constexpr int RazorMargin = 531; @@ -272,9 +272,9 @@ void MainThread::search() { Thread* bestThread = this; // Check if there are threads with a better score than main thread - if ( Options["MultiPV"] == 1 + if ( int(Options["MultiPV"]) == 1 && !Limits.depth - && !(Skill(Options["Skill Level"]).enabled() || Options["UCI_LimitStrength"]) + && !(Skill(Options["Skill Level"]).enabled() || int(Options["UCI_LimitStrength"])) && rootMoves[0].pv[0] != MOVE_NONE) { std::map votes; @@ -350,14 +350,17 @@ void Thread::search() { if (mainThread) { if (mainThread->bestPreviousScore == VALUE_INFINITE) - for (int i=0; i<4; ++i) + for (int i = 0; i < 4; ++i) mainThread->iterValue[i] = VALUE_ZERO; else - for (int i=0; i<4; ++i) + for (int i = 0; i < 4; ++i) mainThread->iterValue[i] = mainThread->bestPreviousScore; } - size_t multiPV = Options["MultiPV"]; + std::copy(&lowPlyHistory[2][0], &lowPlyHistory.back().back() + 1, &lowPlyHistory[0][0]); + std::fill(&lowPlyHistory[MAX_LPH - 2][0], &lowPlyHistory.back().back() + 1, 0); + + size_t multiPV = size_t(Options["MultiPV"]); // Pick integer skill levels, but non-deterministically round up or down // such that the average integer skill corresponds to the input floating point one. @@ -378,7 +381,7 @@ void Thread::search() { multiPV = std::max(multiPV, (size_t)4); multiPV = std::min(multiPV, rootMoves.size()); - ttHitAverage = ttHitAverageWindow * ttHitAverageResolution / 2; + ttHitAverage = TtHitAverageWindow * TtHitAverageResolution / 2; int ct = int(Options["Contempt"]) * PawnValueEg / 100; // From centipawns @@ -537,8 +540,8 @@ void Thread::search() { && !Threads.stop && !mainThread->stopOnPonderhit) { - double fallingEval = (332 + 6 * (mainThread->bestPreviousScore - bestValue) - + 6 * (mainThread->iterValue[iterIdx] - bestValue)) / 704.0; + double fallingEval = (332 + 6 * (mainThread->bestPreviousScore - bestValue) + + 6 * (mainThread->iterValue[iterIdx] - bestValue)) / 704.0; fallingEval = Utility::clamp(fallingEval, 0.5, 1.5); // If the bestMove is stable over several iterations, reduce time accordingly @@ -627,7 +630,8 @@ namespace { Depth extension, newDepth; Value bestValue, value, ttValue, eval, maxValue; bool ttHit, ttPv, formerPv, givesCheck, improving, didLMR, priorCapture; - bool captureOrPromotion, doFullDepthSearch, moveCountPruning, ttCapture, singularLMR; + bool captureOrPromotion, doFullDepthSearch, moveCountPruning, + ttCapture, singularQuietLMR; Piece movedPiece; int moveCount, captureCount, quietCount; @@ -702,8 +706,8 @@ namespace { thisThread->lowPlyHistory[ss->ply - 1][from_to((ss-1)->currentMove)] << stat_bonus(depth - 5); // thisThread->ttHitAverage can be used to approximate the running average of ttHit - thisThread->ttHitAverage = (ttHitAverageWindow - 1) * thisThread->ttHitAverage / ttHitAverageWindow - + ttHitAverageResolution * ttHit; + thisThread->ttHitAverage = (TtHitAverageWindow - 1) * thisThread->ttHitAverage / TtHitAverageWindow + + TtHitAverageResolution * ttHit; // At non-PV nodes we check for an early TT cutoff if ( !PvNode @@ -968,7 +972,7 @@ moves_loop: // When in check, search starts from here depth > 12 ? ss->ply : MAX_PLY); value = bestValue; - singularLMR = moveCountPruning = false; + singularQuietLMR = moveCountPruning = false; ttCapture = ttMove && pos.capture_or_promotion(ttMove); // Mark this node as being searched @@ -1049,6 +1053,14 @@ moves_loop: // When in check, search starts from here && captureHistory[movedPiece][to_sq(move)][type_of(pos.piece_on(to_sq(move)))] < 0) continue; + // Futility pruning for captures + if ( !givesCheck + && lmrDepth < 6 + && !(PvNode && abs(bestValue) < 2) + && !ss->inCheck + && ss->staticEval + 270 + 384 * lmrDepth + PieceValue[MG][type_of(pos.piece_on(to_sq(move)))] <= alpha) + continue; + // See based pruning if (!pos.see_ge(move, Value(-194) * depth)) // (~25 Elo) continue; @@ -1081,7 +1093,7 @@ moves_loop: // When in check, search starts from here if (value < singularBeta) { extension = 1; - singularLMR = true; + singularQuietLMR = !ttCapture; } // Multi-cut pruning @@ -1163,12 +1175,12 @@ moves_loop: // When in check, search starts from here || moveCountPruning || ss->staticEval + PieceValue[EG][pos.captured_piece()] <= alpha || cutNode - || thisThread->ttHitAverage < 375 * ttHitAverageResolution * ttHitAverageWindow / 1024)) + || thisThread->ttHitAverage < 375 * TtHitAverageResolution * TtHitAverageWindow / 1024)) { Depth r = reduction(improving, depth, moveCount); // Decrease reduction if the ttHit running average is large - if (thisThread->ttHitAverage > 500 * ttHitAverageResolution * ttHitAverageWindow / 1024) + if (thisThread->ttHitAverage > 500 * TtHitAverageResolution * TtHitAverageWindow / 1024) r--; // Reduction if other threads are searching this position. @@ -1187,7 +1199,7 @@ moves_loop: // When in check, search starts from here r--; // Decrease reduction if ttMove has been singularly extended (~3 Elo) - if (singularLMR) + if (singularQuietLMR) r -= 1 + formerPv; if (!captureOrPromotion)