X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=0e68178147c7b2cbba34845c89e57218e6ea9b86;hp=5abbafbcbfcd8b756dbf481efdffff9187e78016;hb=79bcb2ca54aa72bd9e3d1ba1ed1dcb2a4ddf14c9;hpb=d23454854e72e1311363a8c98cd58a5d44c427f9 diff --git a/src/search.cpp b/src/search.cpp index 5abbafbc..0e681781 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -533,7 +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 @@ -643,10 +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 @@ -806,6 +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); @@ -857,7 +858,7 @@ 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 @@ -900,6 +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 @@ -1129,7 +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 @@ -1225,11 +1230,11 @@ split_point_start: // At split points actual search starts from here continue; } - // Prune moves with negative or equal SEE. - // Also prune moves with positive SEE where capturing loses a tempo and SEE < beta - futilityBase. + // 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_asymm(move, beta - futilityBase) <= 0) + && pos.see(move, beta - futilityBase) <= 0) { bestValue = std::max(bestValue, futilityBase); continue; @@ -1579,7 +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