X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=438c2d6fe858d85e1c72f1ed37c0ec73b74f48ce;hp=0416c16cb3c89a9f7606d2ea6b4dd51173f53274;hb=2ef53ee368683d5aa62b028377b94efe961f18ac;hpb=d2eeef89aaf00b0dd090eeb6e80f496995ca6009 diff --git a/src/search.cpp b/src/search.cpp index 0416c16c..438c2d6f 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -440,6 +440,7 @@ namespace { if ( depth >= 12 && !stop && PVSize == 1 + && bestValue > VALUE_MATED_IN_MAX_PLY && ( RootMoves.size() == 1 || Time::now() - SearchTime > (TimeMgr.available_time() * 20) / 100)) { @@ -532,7 +533,7 @@ namespace { if (!RootNode) { // Step 2. Check for aborted search and immediate draw - if (Signals.stop || pos.is_draw() || ss->ply > MAX_PLY) + if (Signals.stop || pos.is_draw() || ss->ply > MAX_PLY) return DrawValue[pos.side_to_move()]; // Step 3. Mate distance pruning. Even if we mate at the next move our score @@ -591,7 +592,7 @@ namespace { // Never assume anything on values stored in TT if ( (ss->staticEval = eval = tte->eval_value()) == VALUE_NONE ||(ss->evalMargin = tte->eval_margin()) == VALUE_NONE) - eval = ss->staticEval = evaluate(pos, ss->evalMargin); + eval = ss->staticEval = evaluate(pos, ss->evalMargin, &ss->ei); // Can ttValue be used as a better position evaluation? if (ttValue != VALUE_NONE) @@ -601,7 +602,7 @@ namespace { } else { - eval = ss->staticEval = evaluate(pos, ss->evalMargin); + eval = ss->staticEval = evaluate(pos, ss->evalMargin, &ss->ei); TT.store(posKey, VALUE_NONE, BOUND_NONE, DEPTH_NONE, MOVE_NONE, ss->staticEval, ss->evalMargin); } @@ -642,10 +643,10 @@ namespace { && !ss->skipNullMove && depth < 4 * ONE_PLY && !inCheck - && eval - FutilityMargins[depth][0] >= beta + && eval - futility_margin(depth, (ss-1)->futilityMoveCount) >= beta && abs(beta) < VALUE_MATE_IN_MAX_PLY && pos.non_pawn_material(pos.side_to_move())) - return eval - FutilityMargins[depth][0]; + return eval - futility_margin(depth, (ss-1)->futilityMoveCount); // Step 8. Null move search with verification search (is omitted in PV nodes) if ( !PvNode @@ -678,7 +679,7 @@ namespace { if (nullValue >= VALUE_MATE_IN_MAX_PLY) nullValue = beta; - if (depth < 6 * ONE_PLY) + if (depth < 12 * ONE_PLY) return nullValue; // Do verification search at high depths @@ -745,7 +746,7 @@ namespace { && ttMove == MOVE_NONE && (PvNode || (!inCheck && ss->staticEval + Value(256) >= beta))) { - Depth d = (PvNode ? depth - 2 * ONE_PLY : depth / 2); + Depth d = depth - 2 * ONE_PLY - (PvNode ? DEPTH_ZERO : depth / 4); ss->skipNullMove = true; search(pos, ss, alpha, beta, d); @@ -805,6 +806,7 @@ split_point_start: // At split points actual search starts from here << " currmovenumber " << moveCount + PVIdx << sync_endl; } + ss->futilityMoveCount = 0; ext = DEPTH_ZERO; captureOrPromotion = pos.is_capture_or_promotion(move); givesCheck = pos.move_gives_check(move, ci); @@ -856,7 +858,8 @@ split_point_start: // At split points actual search starts from here && !captureOrPromotion && !inCheck && !dangerous - && move != ttMove) + /* && move != ttMove Already implicit in the next condition */ + && bestValue > VALUE_MATED_IN_MAX_PLY) { // Move count based pruning if ( depth < 16 * ONE_PLY @@ -878,14 +881,19 @@ split_point_start: // At split points actual search starts from here if (futilityValue < beta) { + bestValue = std::max(bestValue, futilityValue); + if (SpNode) + { splitPoint->mutex.lock(); - + if (bestValue > splitPoint->bestValue) + splitPoint->bestValue = bestValue; + } continue; } // Prune moves with negative SEE at low depths - if ( predictedDepth < 3 * ONE_PLY + if ( predictedDepth < 4 * ONE_PLY && pos.see_sign(move) < 0) { if (SpNode) @@ -893,6 +901,10 @@ split_point_start: // At split points actual search starts from here continue; } + + // We have not pruned the move that will be searched, but remember how + // far in the move list we are to be more aggressive in the child node. + ss->futilityMoveCount = moveCount; } // Check for legality only before to do the move @@ -1122,7 +1134,7 @@ split_point_start: // At split points actual search starts from here ss->ply = (ss-1)->ply + 1; // Check for an instant draw or maximum ply reached - if (pos.is_draw() || ss->ply > MAX_PLY) + if (pos.is_draw() || ss->ply > MAX_PLY) return DrawValue[pos.side_to_move()]; // Decide whether or not to include checks, this fixes also the type of @@ -1163,10 +1175,10 @@ split_point_start: // At split points actual search starts from here // Never assume anything on values stored in TT if ( (ss->staticEval = bestValue = tte->eval_value()) == VALUE_NONE ||(ss->evalMargin = tte->eval_margin()) == VALUE_NONE) - ss->staticEval = bestValue = evaluate(pos, ss->evalMargin); + ss->staticEval = bestValue = evaluate(pos, ss->evalMargin, &ss->ei); } else - ss->staticEval = bestValue = evaluate(pos, ss->evalMargin); + ss->staticEval = bestValue = evaluate(pos, ss->evalMargin, &ss->ei); // Stand pat. Return immediately if static value is at least beta if (bestValue >= beta) @@ -1218,10 +1230,11 @@ split_point_start: // At split points actual search starts from here continue; } - // Prune moves with negative or equal SEE + // Prune moves with negative or equal SEE and also moves with positive + // SEE where capturing piece loses a tempo and SEE < beta - futilityBase. if ( futilityBase < beta && depth < DEPTH_ZERO - && pos.see(move) <= 0) + && pos.see(move, beta - futilityBase) <= 0) { bestValue = std::max(bestValue, futilityBase); continue; @@ -1571,7 +1584,7 @@ void RootMove::extract_pv_from_tt(Position& pos) { && pos.is_pseudo_legal(m = tte->move()) // Local copy, TT could change && pos.pl_move_is_legal(m, pos.pinned_pieces()) && ply < MAX_PLY - && (!pos.is_draw() || ply < 2)); + && (!pos.is_draw() || ply < 2)); pv.push_back(MOVE_NONE); // Must be zero-terminating