From: Marco Costalba Date: Mon, 29 Sep 2014 12:08:56 +0000 (+0200) Subject: Move ONE_PLY to be 1 instead of 2: search() X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=222f59b9c1537f22db65c6104072f5e0f68c1fbc Move ONE_PLY to be 1 instead of 2: search() Now that half-plies are no more used we can simplify the code assuming that ONE_PLY is 1 and no more 2. Verified with a SMP test: LLR: 2.95 (-2.94,2.94) [-4.50,0.00] Total: 8926 W: 1712 L: 1607 D: 5607 No functional change. --- diff --git a/src/search.cpp b/src/search.cpp index fa92aa6f..1317fc23 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -55,21 +55,20 @@ namespace { enum NodeType { Root, PV, NonPV }; // Dynamic razoring margin based on depth - inline Value razor_margin(Depth d) { return Value(512 + 16 * d); } + inline Value razor_margin(Depth d) { return Value(512 + 32 * d); } // Futility lookup tables (initialized at startup) and their access functions int FutilityMoveCounts[2][32]; // [improving][depth] inline Value futility_margin(Depth d) { - return Value(100 * d); + return Value(200 * d); } // Reduction lookup tables (initialized at startup) and their access function int8_t Reductions[2][2][64][64]; // [pv][improving][depth][moveNumber] template inline Depth reduction(bool i, Depth d, int mn) { - - return (Depth) Reductions[PvNode][i][std::min(int(d) / ONE_PLY, 63)][std::min(mn, 63)]; + return (Depth) Reductions[PvNode][i][std::min(int(d), 63)][std::min(mn, 63)]; } size_t PVIdx; @@ -127,21 +126,21 @@ void Search::init() { { double pvRed = 0.00 + log(double(hd)) * log(double(mc)) / 3.00; double nonPVRed = 0.33 + log(double(hd)) * log(double(mc)) / 2.25; - Reductions[1][1][hd][mc] = int8_t( pvRed >= 1.0 ? pvRed+0.5: 0)*int(ONE_PLY); - Reductions[0][1][hd][mc] = int8_t(nonPVRed >= 1.0 ? nonPVRed+0.5: 0)*int(ONE_PLY); + Reductions[1][1][hd][mc] = int8_t( pvRed >= 1.0 ? pvRed + 0.5: 0); + Reductions[0][1][hd][mc] = int8_t(nonPVRed >= 1.0 ? nonPVRed + 0.5: 0); Reductions[1][0][hd][mc] = Reductions[1][1][hd][mc]; Reductions[0][0][hd][mc] = Reductions[0][1][hd][mc]; - if (Reductions[0][0][hd][mc] >= 2 * ONE_PLY) - Reductions[0][0][hd][mc] += ONE_PLY; + if (Reductions[0][0][hd][mc] >= 2) + Reductions[0][0][hd][mc] += 1; } // Init futility move count array for (d = 0; d < 32; ++d) { - FutilityMoveCounts[0][d] = int(2.4 + 0.222 * pow(d + 0.00, 1.8)); - FutilityMoveCounts[1][d] = int(3.0 + 0.300 * pow(d + 0.98, 1.8)); + FutilityMoveCounts[0][d] = int(2.4 + 0.222 * pow(d * 2 + 0.00, 1.8)); + FutilityMoveCounts[1][d] = int(3.0 + 0.300 * pow(d * 2 + 0.98, 1.8)); } } @@ -154,7 +153,7 @@ uint64_t Search::perft(Position& pos, Depth depth) { StateInfo st; uint64_t cnt, nodes = 0; CheckInfo ci(pos); - const bool leaf = depth == 2 * ONE_PLY; + const bool leaf = (depth == 2 * ONE_PLY); for (MoveList it(pos); *it; ++it) { @@ -561,8 +560,7 @@ namespace { assert(eval - beta >= 0); // Null move dynamic reduction based on depth and value - Depth R = (3 + (depth / 8 )) * ONE_PLY - + std::min(int(eval - beta) / PawnValueMg, 3) * ONE_PLY; + Depth R = (3 + depth / 4 + std::min(int(eval - beta) / PawnValueMg, 3)) * ONE_PLY; pos.do_null_move(st); (ss+1)->skipNullMove = true; @@ -627,10 +625,9 @@ namespace { && !ttMove && (PvNode || ss->staticEval + 256 >= beta)) { - Depth d = depth - 2 * ONE_PLY - (PvNode ? DEPTH_ZERO : depth / 4); - d = (d / 2) * 2; // Round to nearest full-ply + Depth d = 2 * (depth - 2 * ONE_PLY) - (PvNode ? DEPTH_ZERO : depth / 2); ss->skipNullMove = true; - search(pos, ss, alpha, beta, d, true); + search(pos, ss, alpha, beta, d / 2, true); ss->skipNullMove = false; tte = TT.probe(posKey); @@ -696,7 +693,7 @@ moves_loop: // When in check and at SpNode search starts from here Signals.firstRootMove = (moveCount == 1); if (thisThread == Threads.main() && Time::now() - SearchTime > 3000) - sync_cout << "info depth " << depth / ONE_PLY + sync_cout << "info depth " << depth << " currmove " << move_to_uci(move, pos.is_chess960()) << " currmovenumber " << moveCount + PVIdx << sync_endl; } @@ -726,10 +723,10 @@ moves_loop: // When in check and at SpNode search starts from here && !ext && pos.legal(move, ci.pinned)) { - Value rBeta = ttValue - int(depth); + Value rBeta = ttValue - int(2 * depth); ss->excludedMove = move; ss->skipNullMove = true; - value = search(pos, ss, rBeta - 1, rBeta, (depth / 4) * 2, cutNode); + value = search(pos, ss, rBeta - 1, rBeta, depth / 2, cutNode); ss->skipNullMove = false; ss->excludedMove = MOVE_NONE; @@ -750,7 +747,7 @@ moves_loop: // When in check and at SpNode search starts from here { // Move count based pruning if ( depth < 16 * ONE_PLY - && moveCount >= FutilityMoveCounts[improving][depth] ) + && moveCount >= FutilityMoveCounts[improving][depth]) { if (SpNode) splitPoint->mutex.lock(); @@ -763,8 +760,8 @@ moves_loop: // When in check and at SpNode search starts from here // Futility pruning: parent node if (predictedDepth < 7 * ONE_PLY) { - futilityValue = ss->staticEval + futility_margin(predictedDepth) - + 128 + Gains[pos.moved_piece(move)][to_sq(move)]; + futilityValue = ss->staticEval + futility_margin(predictedDepth) + + 128 + Gains[pos.moved_piece(move)][to_sq(move)]; if (futilityValue <= alpha) { @@ -855,20 +852,20 @@ moves_loop: // When in check and at SpNode search starts from here if (SpNode) alpha = splitPoint->alpha; - value = newDepth < ONE_PLY ? - givesCheck ? -qsearch(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO) - : -qsearch(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO) - : - search(pos, ss+1, -(alpha+1), -alpha, newDepth, !cutNode); + value = newDepth < ONE_PLY ? + givesCheck ? -qsearch(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO) + : -qsearch(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO) + : - search(pos, ss+1, -(alpha+1), -alpha, newDepth, !cutNode); } // For PV nodes only, do a full PV search on the first move or after a fail // high (in the latter case search only if value < beta), otherwise let the // parent node fail low with value <= alpha and to try another move. if (PvNode && (pvMove || (value > alpha && (RootNode || value < beta)))) - value = newDepth < ONE_PLY ? - givesCheck ? -qsearch(pos, ss+1, -beta, -alpha, DEPTH_ZERO) - : -qsearch(pos, ss+1, -beta, -alpha, DEPTH_ZERO) - : - search(pos, ss+1, -beta, -alpha, newDepth, false); + value = newDepth < ONE_PLY ? + givesCheck ? -qsearch(pos, ss+1, -beta, -alpha, DEPTH_ZERO) + : -qsearch(pos, ss+1, -beta, -alpha, DEPTH_ZERO) + : - search(pos, ss+1, -beta, -alpha, newDepth, false); // Step 17. Undo move pos.undo_move(move); @@ -1229,7 +1226,7 @@ moves_loop: // When in check and at SpNode search starts from here // Increase history value of the cut-off move and decrease all the other // played quiet moves. - Value bonus = Value(int(depth) * int(depth)); + Value bonus = Value(4 * int(depth) * int(depth)); History.update(pos.moved_piece(move), to_sq(move), bonus); for (int i = 0; i < quietsCnt; ++i) { diff --git a/src/types.h b/src/types.h index f921f9e1..3ff07ee7 100644 --- a/src/types.h +++ b/src/types.h @@ -211,14 +211,14 @@ enum Piece { enum Depth { - ONE_PLY = 2, + ONE_PLY = 1, - DEPTH_ZERO = 0 * ONE_PLY, - DEPTH_QS_CHECKS = 0 * ONE_PLY, - DEPTH_QS_NO_CHECKS = -1 * ONE_PLY, - DEPTH_QS_RECAPTURES = -5 * ONE_PLY, + DEPTH_ZERO = 0, + DEPTH_QS_CHECKS = 0, + DEPTH_QS_NO_CHECKS = -1, + DEPTH_QS_RECAPTURES = -5, - DEPTH_NONE = -6 * ONE_PLY + DEPTH_NONE = -6 }; enum Square {