From: Marco Costalba Date: Wed, 29 Dec 2010 07:47:14 +0000 (+0100) Subject: Use rml[0].pv[] instead of dedicated pv[] array X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=d2a4aac53d8eb2cf21e0b8f1154412b1edd5afae;hp=58c6e64069cc2d278756fb2e73f54ca5346ec35d Use rml[0].pv[] instead of dedicated pv[] array We have a small functionality change in case we have a fail-high so that both rml[].pv and pv[] are updated, but if, after researching, we have a fail-low then rml score is updated again but pv[] remains the same and coming back from search we used a PV line that has failed-low (after having failed-high). With this patch we always use the 'correct' PV line, i.e. the line with highest score at the end of the whole search. Retire also redundant RootMove's 'move' member and directly use pv[0] instead. --- diff --git a/src/search.cpp b/src/search.cpp index b75b6fa8..fceaccb5 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -124,14 +124,12 @@ namespace { // way we are guaranteed that PV moves are always sorted as first. bool operator<(const RootMove& m) const { return pv_score != m.pv_score ? pv_score < m.pv_score - : non_pv_score <= m.non_pv_score; + : non_pv_score < m.non_pv_score; } - void set_pv(const Move newPv[]); int64_t nodes; Value pv_score; Value non_pv_score; - Move move; Move pv[PLY_MAX_PLUS_2]; }; @@ -139,26 +137,23 @@ namespace { nodes = 0; pv_score = non_pv_score = -VALUE_INFINITE; - move = pv[0] = MOVE_NONE; + pv[0] = MOVE_NONE; } RootMove& RootMove::operator=(const RootMove& rm) { + const Move* src = rm.pv; + Move* dst = pv; + + // Avoid a costly full rm.pv[] copy + do *dst++ = *src; while (*src++ != MOVE_NONE); + nodes = rm.nodes; pv_score = rm.pv_score; non_pv_score = rm.non_pv_score; - move = rm.move; - set_pv(rm.pv); // Skip costly full pv[] copy return *this; } - void RootMove::set_pv(const Move newPv[]) { - - Move* p = pv; - - do *p++ = *newPv; while (*newPv++ != MOVE_NONE); - } - // RootMoveList struct is essentially a std::vector<> of RootMove objects, // with an handful of methods above the standard ones. @@ -298,7 +293,7 @@ namespace { /// Local functions Value id_loop(Position& pos, Move searchMoves[]); - Value root_search(Position& pos, SearchStack* ss, Move* pv, RootMoveList& rml, Value* alphaPtr, Value* betaPtr); + Value root_search(Position& pos, SearchStack* ss, RootMoveList& rml, Value* alphaPtr, Value* betaPtr); template Value search(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, int ply); @@ -538,7 +533,6 @@ namespace { Value id_loop(Position& pos, Move searchMoves[]) { SearchStack ss[PLY_MAX_PLUS_2]; - Move pv[PLY_MAX_PLUS_2]; Move EasyMove = MOVE_NONE; Value value, alpha = -VALUE_INFINITE, beta = VALUE_INFINITE; @@ -563,20 +557,19 @@ namespace { << " time " << current_search_time() << " nodes " << pos.nodes_searched() << " nps " << nps(pos) - << " pv " << rml[0].move << "\n"; + << " pv " << rml[0].pv[0] << "\n"; // Initialize TT.new_search(); H.clear(); init_ss_array(ss, PLY_MAX_PLUS_2); - pv[0] = pv[1] = MOVE_NONE; ValueByIteration[1] = rml[0].pv_score; Iteration = 1; // Is one move significantly better than others after initial scoring ? if ( rml.size() == 1 || rml[0].pv_score > rml[1].pv_score + EasyMoveMargin) - EasyMove = rml[0].move; + EasyMove = rml[0].pv[0]; // Iterative deepening loop while (Iteration < PLY_MAX) @@ -601,11 +594,7 @@ namespace { } // Search to the current depth, rml is updated and sorted, alpha and beta could change - value = root_search(pos, ss, pv, rml, &alpha, &beta); - - // Write PV to transposition table, in case the relevant entries have - // been overwritten during the search. - insert_pv_in_tt(pos, pv); + value = root_search(pos, ss, rml, &alpha, &beta); if (AbortSearch) break; // Value cannot be trusted. Break out immediately! @@ -614,7 +603,7 @@ namespace { ValueByIteration[Iteration] = value; // Drop the easy move if differs from the new best move - if (pv[0] != EasyMove) + if (rml[0].pv[0] != EasyMove) EasyMove = MOVE_NONE; if (UseTimeManagement) @@ -635,7 +624,7 @@ namespace { // Stop search early if one move seems to be much better than the others if ( Iteration >= 8 - && EasyMove == pv[0] + && EasyMove == rml[0].pv[0] && ( ( rml[0].nodes > (pos.nodes_searched() * 85) / 100 && current_search_time() > TimeMgr.available_time() / 16) ||( rml[0].nodes > (pos.nodes_searched() * 98) / 100 @@ -677,18 +666,10 @@ namespace { << " time " << current_search_time() << endl; // Print the best move and the ponder move to the standard output - if (pv[0] == MOVE_NONE || MultiPV > 1) - { - pv[0] = rml[0].move; - pv[1] = MOVE_NONE; - } + cout << "bestmove " << rml[0].pv[0]; - assert(pv[0] != MOVE_NONE); - - cout << "bestmove " << pv[0]; - - if (pv[1] != MOVE_NONE) - cout << " ponder " << pv[1]; + if (rml[0].pv[1] != MOVE_NONE) + cout << " ponder " << rml[0].pv[1]; cout << endl; @@ -702,12 +683,12 @@ namespace { LogFile << "\nNodes: " << pos.nodes_searched() << "\nNodes/second: " << nps(pos) - << "\nBest move: " << move_to_san(pos, pv[0]); + << "\nBest move: " << move_to_san(pos, rml[0].pv[0]); StateInfo st; - pos.do_move(pv[0], st); + pos.do_move(rml[0].pv[0], st); LogFile << "\nPonder move: " - << move_to_san(pos, pv[1]) // Works also with MOVE_NONE + << move_to_san(pos, rml[0].pv[1]) // Works also with MOVE_NONE << endl; } return rml[0].pv_score; @@ -719,7 +700,7 @@ namespace { // scheme, prints some information to the standard output and handles // the fail low/high loops. - Value root_search(Position& pos, SearchStack* ss, Move* pv, RootMoveList& rml, Value* alphaPtr, Value* betaPtr) { + Value root_search(Position& pos, SearchStack* ss, RootMoveList& rml, Value* alphaPtr, Value* betaPtr) { StateInfo st; CheckInfo ci(pos); @@ -773,7 +754,7 @@ namespace { // Pick the next root move, and print the move and the move number to // the standard output. - move = ss->currentMove = rml[i].move; + move = ss->currentMove = rml[i].pv[0]; if (current_search_time() >= 1000) cout << "info currmove " << move @@ -857,11 +838,10 @@ namespace { // the score before research in case we run out of time while researching. rml[i].pv_score = value; ss->bestMove = move; - extract_pv_from_tt(pos, move, pv); - rml[i].set_pv(pv); + extract_pv_from_tt(pos, move, rml[i].pv); // Print information to the standard output - print_pv_info(pos, pv, alpha, beta, value); + print_pv_info(pos, rml[i].pv, alpha, beta, value); // Prepare for a research after a fail high, each time with a wider window *betaPtr = beta = Min(beta + AspirationDelta * (1 << researchCountFH), VALUE_INFINITE); @@ -893,8 +873,7 @@ namespace { // Update PV rml[i].pv_score = value; ss->bestMove = move; - extract_pv_from_tt(pos, move, pv); - rml[i].set_pv(pv); + extract_pv_from_tt(pos, move, rml[i].pv); if (MultiPV == 1) { @@ -905,7 +884,7 @@ namespace { BestMoveChangesByIteration[Iteration]++; // Print information to the standard output - print_pv_info(pos, pv, alpha, beta, value); + print_pv_info(pos, rml[i].pv, alpha, beta, value); // Raise alpha to setup proper non-pv search upper bound if (value > alpha) @@ -954,6 +933,10 @@ namespace { // Sort the moves before to return rml.sort(); + // Write PV to transposition table, in case the relevant entries have + // been overwritten during the search. + insert_pv_in_tt(pos, rml[0].pv); + return alpha; } @@ -2687,7 +2670,7 @@ split_point_start: // At split points actual search starts from here pos.do_move(cur->move, st); RootMove rm; - rm.move = ss[0].currentMove = rm.pv[0] = cur->move; + rm.pv[0] = ss[0].currentMove = cur->move; rm.pv[1] = MOVE_NONE; rm.pv_score = -qsearch(pos, ss+1, -VALUE_INFINITE, VALUE_INFINITE, DEPTH_ZERO, 1); push_back(rm); @@ -2710,7 +2693,7 @@ split_point_start: // At split points actual search starts from here while ((move = mp.get_next_move()) != MOVE_NONE) for (Base::iterator it = begin(); it != end(); ++it) - if (it->move == move) + if (it->pv[0] == move) { it->non_pv_score = score--; break;