X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=84f9bb23f0e01925be290646e80f1e1390c15275;hp=ec9c6b1d0507c77734f92fe8d3a7d067de2334d4;hb=3b70932b0dee0cf1817baf0daa43ac92e18003c4;hpb=69204f0720bba198952fb7a848ed4377430ef433 diff --git a/src/search.cpp b/src/search.cpp index ec9c6b1d..84f9bb23 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -158,7 +158,7 @@ namespace { void update_continuation_histories(Stack* ss, Piece pc, Square to, int bonus); void update_quiet_stats(const Position& pos, Stack* ss, Move move, int bonus); void update_all_stats(const Position& pos, Stack* ss, Move bestMove, Value bestValue, Value beta, Square prevSq, - Move* quietsSearched, int quietCount, Move* capturesSearched, int captureCount, Depth depth); + Move* quietsSearched, int quietCount, Move* capturesSearched, int captureCount, Depth depth, bool pastPV); // perft() is our utility to verify move generation. All the leaf nodes up // to the given depth are generated and counted, and the sum is returned. @@ -564,6 +564,7 @@ void Thread::search() { Threads.stop = true; } else if ( Threads.increaseDepth + && !mainThread->ponder && Time.elapsed() > Time.optimum() * fallingEval * reduction * bestMoveInstability * 0.6) Threads.increaseDepth = false; else @@ -712,7 +713,7 @@ namespace { if (ttValue >= beta) { if (!pos.capture_or_promotion(ttMove)) - update_quiet_stats(pos, ss, ttMove, stat_bonus(depth)); + update_quiet_stats(pos, ss, ttMove, stat_bonus(depth + (!PvNode && ttPv))); // Extra penalty for early quiet moves of the previous ply if ((ss-1)->moveCount <= 2 && !priorCapture) @@ -721,7 +722,7 @@ namespace { // Penalty for a quiet ttMove that fails low else if (!pos.capture_or_promotion(ttMove)) { - int penalty = -stat_bonus(depth); + int penalty = -stat_bonus(depth + (!PvNode && ttPv)); thisThread->mainHistory[us][from_to(ttMove)] << penalty; update_continuation_histories(ss, pos.moved_piece(ttMove), to_sq(ttMove), penalty); } @@ -824,8 +825,8 @@ namespace { && eval <= alpha - RazorMargin) return qsearch(pos, ss, alpha, beta); - improving = (ss-2)->staticEval == VALUE_NONE ? (ss->staticEval >= (ss-4)->staticEval - || (ss-4)->staticEval == VALUE_NONE) : ss->staticEval >= (ss-2)->staticEval; + improving = (ss-2)->staticEval == VALUE_NONE ? (ss->staticEval > (ss-4)->staticEval + || (ss-4)->staticEval == VALUE_NONE) : ss->staticEval > (ss-2)->staticEval; // Step 8. Futility pruning: child node (~50 Elo) if ( !PvNode @@ -840,7 +841,7 @@ namespace { && (ss-1)->statScore < 23397 && eval >= beta && eval >= ss->staticEval - && ss->staticEval >= beta - 32 * depth + 292 - improving * 30 + && ss->staticEval >= beta - 32 * depth - 30 * improving + 120 * ttPv + 292 && !excludedMove && pos.non_pawn_material(us) && (ss->ply >= thisThread->nmpMinPly || us != thisThread->nmpColor)) @@ -1015,11 +1016,11 @@ moves_loop: // When in check, search starts from here // Futility pruning: parent node (~5 Elo) if ( lmrDepth < 6 && !inCheck - && ss->staticEval + 255 + 182 * lmrDepth <= alpha + && ss->staticEval + 235 + 172 * lmrDepth <= alpha && thisThread->mainHistory[us][from_to(move)] + (*contHist[0])[movedPiece][to_sq(move)] + (*contHist[1])[movedPiece][to_sq(move)] - + (*contHist[3])[movedPiece][to_sq(move)] < 30000) + + (*contHist[3])[movedPiece][to_sq(move)] < 25000) continue; // Prune moves with negative SEE (~20 Elo) @@ -1027,7 +1028,11 @@ moves_loop: // When in check, search starts from here continue; } else if (!pos.see_ge(move, Value(-194) * depth)) // (~25 Elo) - continue; + { + if (captureOrPromotion && captureCount < 32) + capturesSearched[captureCount++] = move; + continue; + } } // Step 14. Extensions (~75 Elo) @@ -1114,7 +1119,7 @@ moves_loop: // When in check, search starts from here // Step 16. Reduced depth search (LMR, ~200 Elo). If the move fails high it will be // re-searched at full depth. if ( depth >= 3 - && moveCount > 1 + 2 * rootNode + && moveCount > 1 + rootNode + (rootNode && bestValue < alpha) && (!rootNode || thisThread->best_move_count(move) == 0) && ( !captureOrPromotion || moveCountPruning @@ -1159,7 +1164,7 @@ moves_loop: // When in check, search starts from here // hence break make_move(). (~2 Elo) else if ( type_of(move) == NORMAL && !pos.see_ge(reverse_move(move))) - r -= 2; + r -= 2 + ttPv; ss->statScore = thisThread->mainHistory[us][from_to(move)] + (*contHist[0])[movedPiece][to_sq(move)] @@ -1185,6 +1190,10 @@ moves_loop: // When in check, search starts from here r -= ss->statScore / 16384; } + // Increase reduction for captures/promotions if late move and at low depth + else if (depth < 8 && moveCount > 2) + r++; + Depth d = clamp(newDepth - r, 1, newDepth); value = -search(pos, ss+1, -(alpha+1), -alpha, d, true); @@ -1317,7 +1326,7 @@ moves_loop: // When in check, search starts from here else if (bestMove) update_all_stats(pos, ss, bestMove, bestValue, beta, prevSq, - quietsSearched, quietCount, capturesSearched, captureCount, depth); + quietsSearched, quietCount, capturesSearched, captureCount, depth, (!PvNode && ttPv)); // Bonus for prior countermove that caused the fail low else if ( (depth >= 3 || PvNode) @@ -1593,7 +1602,7 @@ moves_loop: // When in check, search starts from here // update_all_stats() updates stats at the end of search() when a bestMove is found void update_all_stats(const Position& pos, Stack* ss, Move bestMove, Value bestValue, Value beta, Square prevSq, - Move* quietsSearched, int quietCount, Move* capturesSearched, int captureCount, Depth depth) { + Move* quietsSearched, int quietCount, Move* capturesSearched, int captureCount, Depth depth, bool pastPV) { int bonus1, bonus2; Color us = pos.side_to_move(); @@ -1603,8 +1612,8 @@ moves_loop: // When in check, search starts from here PieceType captured = type_of(pos.piece_on(to_sq(bestMove))); bonus1 = stat_bonus(depth + 1); - bonus2 = bestValue > beta + PawnValueMg ? bonus1 // larger bonus - : stat_bonus(depth); // smaller bonus + bonus2 = pastPV || bestValue > beta + PawnValueMg ? bonus1 // larger bonus + : stat_bonus(depth); // smaller bonus if (!pos.capture_or_promotion(bestMove)) {