X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=1d930dd540d160bfaa1c1aad948f0315c7dcf877;hp=a58231d22fe79e85e21a62c3d86a27ec5ad994f2;hb=ace8e951d70c2986a0af83effcc0d2b2312d29e3;hpb=ca6c9f85a5c3a45a248716b8fe68821b20eee201 diff --git a/src/search.cpp b/src/search.cpp index a58231d2..1d930dd5 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -920,41 +920,47 @@ moves_loop: // When in check search starts from here newDepth = depth - ONE_PLY + extension; // Step 13. Pruning at shallow depth - if ( !rootNode - && !captureOrPromotion - && !inCheck - && !givesCheck - && bestValue > VALUE_MATED_IN_MAX_PLY - && !pos.advanced_pawn_push(move)) + if ( !rootNode + && !inCheck + && bestValue > VALUE_MATED_IN_MAX_PLY) { - // Move count based pruning - if (moveCountPruning) - continue; + if ( !captureOrPromotion + && !givesCheck + && !pos.advanced_pawn_push(move)) + { + // Move count based pruning + if (moveCountPruning) + continue; - predictedDepth = std::max(newDepth - reduction(improving, depth, moveCount), DEPTH_ZERO); + predictedDepth = std::max(newDepth - reduction(improving, depth, moveCount), DEPTH_ZERO); - // Countermoves based pruning - if ( predictedDepth < 3 * ONE_PLY - && (!cmh || (*cmh )[moved_piece][to_sq(move)] < VALUE_ZERO) - && (!fmh || (*fmh )[moved_piece][to_sq(move)] < VALUE_ZERO) - && (!fmh2 || (*fmh2)[moved_piece][to_sq(move)] < VALUE_ZERO || (cmh && fmh))) - continue; + // Countermoves based pruning + if ( predictedDepth < 3 * ONE_PLY + && (!cmh || (*cmh )[moved_piece][to_sq(move)] < VALUE_ZERO) + && (!fmh || (*fmh )[moved_piece][to_sq(move)] < VALUE_ZERO) + && (!fmh2 || (*fmh2)[moved_piece][to_sq(move)] < VALUE_ZERO || (cmh && fmh))) + continue; - // Futility pruning: parent node - if ( predictedDepth < 7 * ONE_PLY - && ss->staticEval + 256 + 200 * predictedDepth / ONE_PLY <= alpha) - continue; + // Futility pruning: parent node + if ( predictedDepth < 7 * ONE_PLY + && ss->staticEval + 256 + 200 * predictedDepth / ONE_PLY <= alpha) + continue; - // Prune moves with negative SEE at low depths and below a decreasing - // threshold at higher depths. - if (predictedDepth < 8 * ONE_PLY) - { - Value see_v = predictedDepth < 4 * ONE_PLY ? VALUE_ZERO - : -PawnValueMg * 2 * int(predictedDepth - 3 * ONE_PLY) / ONE_PLY; + // Prune moves with negative SEE at low depths and below a decreasing + // threshold at higher depths. + if (predictedDepth < 8 * ONE_PLY) + { + Value see_v = predictedDepth < 4 * ONE_PLY ? VALUE_ZERO + : -PawnValueMg * 2 * int(predictedDepth - 3 * ONE_PLY) / ONE_PLY; - if (pos.see_sign(move) < see_v) - continue; + if (pos.see_sign(move) < see_v) + continue; + } } + else if ( depth < 3 * ONE_PLY + && ( mp.see_sign() < 0 + || (!mp.see_sign() && pos.see_sign(move) < VALUE_ZERO))) + continue; } // Speculative prefetch as early as possible