X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=f7d3a9fd20f0be04863b1447a1ad622cc91f0fa6;hp=52e7600b073e2e2617c894dfdae1d71a94f3e8f1;hb=3b49aeb4f22569c2b5d5ca830858c4dd584fae7f;hpb=98cd8239cc351f337132bb8cf08be728580c078d diff --git a/src/search.cpp b/src/search.cpp index 52e7600b..f7d3a9fd 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -208,7 +208,7 @@ void Search::think() { if (Options["Contempt Factor"] && !Options["UCI_AnalyseMode"]) { int cf = Options["Contempt Factor"] * PawnValueMg / 100; // From centipawns - cf = cf * MaterialTable::game_phase(RootPos) / PHASE_MIDGAME; // Scale down with phase + cf = cf * Material::game_phase(RootPos) / PHASE_MIDGAME; // Scale down with phase DrawValue[ RootColor] = VALUE_DRAW - Value(cf); DrawValue[~RootColor] = VALUE_DRAW + Value(cf); } @@ -1003,9 +1003,10 @@ split_point_start: // At split points actual search starts from here // Step 19. Check for splitting the search if ( !SpNode && depth >= Threads.min_split_depth() - && bestValue < beta && Threads.available_slave_exists(thisThread)) { + assert(bestValue < beta); + bestValue = Threads.split(pos, ss, alpha, beta, bestValue, &bestMove, depth, threatMove, moveCount, mp, NT); if (bestValue >= beta) @@ -1090,7 +1091,7 @@ split_point_start: // At split points actual search starts from here Key posKey; Move ttMove, move, bestMove; Value bestValue, value, ttValue, futilityValue, futilityBase, oldAlpha; - bool givesCheck, enoughMaterial, evasionPrunable; + bool givesCheck, enoughMaterial, evasionPrunable, fromNull; Depth ttDepth; // To flag BOUND_EXACT a node with eval above alpha and no available moves @@ -1099,6 +1100,7 @@ split_point_start: // At split points actual search starts from here ss->currentMove = bestMove = MOVE_NONE; ss->ply = (ss-1)->ply + 1; + fromNull = (ss-1)->currentMove == MOVE_NULL; // Check for an instant draw or maximum ply reached if (pos.is_draw() || ss->ply > MAX_PLY) @@ -1136,7 +1138,14 @@ split_point_start: // At split points actual search starts from here } else { - ss->staticEval = bestValue = evaluate(pos, ss->evalMargin); + if (fromNull) + { + // Approximated score. Real one is slightly higher due to tempo + ss->staticEval = bestValue = -(ss-1)->staticEval; + ss->evalMargin = VALUE_ZERO; + } + else + ss->staticEval = bestValue = evaluate(pos, ss->evalMargin); // Stand pat. Return immediately if static value is at least beta if (bestValue >= beta) @@ -1171,6 +1180,7 @@ split_point_start: // At split points actual search starts from here // Futility pruning if ( !PvNode && !InCheck + && !fromNull && !givesCheck && move != ttMove && enoughMaterial @@ -1530,7 +1540,8 @@ void RootMove::extract_pv_from_tt(Position& pos) { do { pv.push_back(m); - assert(pos.move_is_legal(pv[ply])); + assert(MoveList(pos).contains(pv[ply])); + pos.do_move(pv[ply++], *st++); tte = TT.probe(pos.key()); @@ -1562,7 +1573,8 @@ void RootMove::insert_pv_in_tt(Position& pos) { if (!tte || tte->move() != pv[ply]) // Don't overwrite correct entries TT.store(pos.key(), VALUE_NONE, BOUND_NONE, DEPTH_NONE, pv[ply]); - assert(pos.move_is_legal(pv[ply])); + assert(MoveList(pos).contains(pv[ply])); + pos.do_move(pv[ply++], *st++); } while (pv[ply] != MOVE_NONE);