X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=5abbafbcbfcd8b756dbf481efdffff9187e78016;hp=e246512e985bbccff13c91c307454f680dd24356;hb=d23454854e72e1311363a8c98cd58a5d44c427f9;hpb=6e2371a86bd987487d836482cd9bbe4ceaac2ef7 diff --git a/src/search.cpp b/src/search.cpp index e246512e..5abbafbc 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -679,7 +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 @@ -876,7 +876,7 @@ split_point_start: // At split points actual search starts from here // but fixing this made program slightly weaker. Depth predictedDepth = newDepth - reduction(depth, moveCount); futilityValue = ss->staticEval + ss->evalMargin + futility_margin(predictedDepth, moveCount) - + 2 * Gain[pos.piece_moved(move)][to_sq(move)]; + + Gain[pos.piece_moved(move)][to_sq(move)]; if (futilityValue < beta) { @@ -1225,10 +1225,11 @@ 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. + // Also prune moves with positive SEE where capturing loses a tempo and SEE < beta - futilityBase. if ( futilityBase < beta && depth < DEPTH_ZERO - && pos.see(move) <= 0) + && pos.see_asymm(move, beta - futilityBase) <= 0) { bestValue = std::max(bestValue, futilityBase); continue;