X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftt.cpp;h=d887844caf12eccae99b84c63ffc9d15a193ef48;hp=26436806c80fff71d0addb59e255d90fb9e72996;hb=865b71309c4dd5c6c67c9c9422df5790cbb22440;hpb=ecd07e51d0f03ccd3e41e5634518b299989254dd diff --git a/src/tt.cpp b/src/tt.cpp index 26436806..d887844c 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) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2014 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 @@ -26,11 +26,11 @@ TranspositionTable TT; // Our global transposition table -/// TranspositionTable::set_size() sets the size of the transposition table, +/// TranspositionTable::resize() sets the size of the transposition table, /// measured in megabytes. Transposition table consists of a power of 2 number /// of clusters and each cluster consists of ClusterSize number of TTEntry. -void TranspositionTable::set_size(size_t mbSize) { +void TranspositionTable::resize(uint64_t mbSize) { assert(msb((mbSize << 20) / sizeof(TTEntry)) < 32); @@ -70,12 +70,15 @@ void TranspositionTable::clear() { const TTEntry* TranspositionTable::probe(const Key key) const { - const TTEntry* tte = first_entry(key); + TTEntry* tte = first_entry(key); uint32_t key32 = key >> 32; for (unsigned i = 0; i < ClusterSize; ++i, ++tte) - if (tte->key() == key32) + if (tte->key32 == key32) + { + tte->generation8 = generation; // Refresh return tte; + } return NULL; } @@ -83,15 +86,14 @@ const TTEntry* TranspositionTable::probe(const Key key) const { /// 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. -/// When a new entry is written and there are no empty entries available in cluster, -/// it replaces the least valuable of entries. A TTEntry t1 is considered to be -/// more valuable than a TTEntry t2 if t1 is from the current search and t2 is from -/// a previous search, or if the depth of t1 is bigger than the depth of t2. +/// key are used to decide in which cluster the position will be placed. +/// When a new entry is written and there are no empty entries available in the +/// cluster, it replaces the least valuable of the entries. A TTEntry t1 is considered +/// to be more valuable than a TTEntry t2 if t1 is from the current search and t2 +/// is from a previous search, or if the depth of t1 is bigger than the depth of t2. void TranspositionTable::store(const Key key, Value v, Bound b, Depth d, Move m, Value statV) { - int c1, c2, c3; TTEntry *tte, *replace; uint32_t key32 = key >> 32; // Use the high 32 bits as key inside the cluster @@ -99,7 +101,7 @@ void TranspositionTable::store(const Key key, Value v, Bound b, Depth d, Move m, for (unsigned i = 0; i < ClusterSize; ++i, ++tte) { - if (!tte->key() || tte->key() == key32) // Empty or overwrite old + if (!tte->key32 || tte->key32 == key32) // Empty or overwrite old { if (!m) m = tte->move(); // Preserve any existing ttMove @@ -109,11 +111,9 @@ void TranspositionTable::store(const Key key, Value v, Bound b, Depth d, Move m, } // Implement replace strategy - c1 = (replace->generation() == generation ? 2 : 0); - c2 = (tte->generation() == generation || tte->bound() == BOUND_EXACT ? -2 : 0); - c3 = (tte->depth() < replace->depth() ? 1 : 0); - - if (c1 + c2 + c3 > 0) + if ( (replace->generation8 == generation) * 2 + - (tte->generation8 == generation || tte->bound() == BOUND_EXACT) * 2 + + (tte->depth16 < replace->depth16) > 0) replace = tte; }