X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftt.cpp;h=0d85d03006b26bd1cedc54c881b0f890dc2a252f;hp=f4e5535430d85a47246b3921196171ac1af7dd14;hb=203fdc9ac1b0ad5e5820b450a0cffdffb917e069;hpb=a7cdf7299a771949332f8c7ef77ae8fd125d0f08 diff --git a/src/tt.cpp b/src/tt.cpp index f4e55354..0d85d030 100644 --- a/src/tt.cpp +++ b/src/tt.cpp @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -40,17 +40,17 @@ void TranspositionTable::set_size(size_t mbSize) { return; hashMask = size - ClusterSize; - delete [] table; - table = new (std::nothrow) TTEntry[size]; + free(mem); + mem = calloc(size * sizeof(TTEntry) + CACHE_LINE_SIZE - 1, 1); - if (!table) + if (!mem) { std::cerr << "Failed to allocate " << mbSize << "MB for transposition table." << std::endl; exit(EXIT_FAILURE); } - clear(); // Operator new is not guaranteed to initialize memory to zero + table = (TTEntry*)((uintptr_t(mem) + CACHE_LINE_SIZE - 1) & ~(CACHE_LINE_SIZE - 1)); } @@ -64,6 +64,23 @@ void TranspositionTable::clear() { } +/// TranspositionTable::probe() looks up the current position in the +/// transposition table. Returns a pointer to the TTEntry or NULL if +/// position is not found. + +const TTEntry* TranspositionTable::probe(const Key key) const { + + const TTEntry* tte = first_entry(key); + uint32_t key32 = key >> 32; + + for (unsigned i = 0; i < ClusterSize; i++, tte++) + if (tte->key() == key32) + return tte; + + return NULL; +} + + /// TranspositionTable::store() writes a new entry containing position key and /// valuable information of current position. The lowest order bits of position /// key are used to decide on which cluster the position will be placed. @@ -84,38 +101,21 @@ void TranspositionTable::store(const Key key, Value v, Bound t, Depth d, Move m, { if (!tte->key() || tte->key() == key32) // Empty or overwrite old { - // Preserve any existing ttMove - if (m == MOVE_NONE) - m = tte->move(); + if (!m) + m = tte->move(); // Preserve any existing ttMove - tte->save(key32, v, t, d, m, generation, statV, kingD); - return; + replace = tte; + break; } // Implement replace strategy c1 = (replace->generation() == generation ? 2 : 0); - c2 = (tte->generation() == generation || tte->type() == BOUND_EXACT ? -2 : 0); + c2 = (tte->generation() == generation || tte->bound() == BOUND_EXACT ? -2 : 0); c3 = (tte->depth() < replace->depth() ? 1 : 0); if (c1 + c2 + c3 > 0) replace = tte; } - replace->save(key32, v, t, d, m, generation, statV, kingD); -} - - -/// TranspositionTable::probe() looks up the current position in the -/// transposition table. Returns a pointer to the TTEntry or NULL if -/// position is not found. - -TTEntry* TranspositionTable::probe(const Key key) const { - TTEntry* tte = first_entry(key); - uint32_t key32 = key >> 32; - - for (unsigned i = 0; i < ClusterSize; i++, tte++) - if (tte->key() == key32) - return tte; - - return NULL; + replace->save(key32, v, t, d, m, generation, statV, kingD); }