X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftt.h;h=272e752b3157c6237fd62fb5fc3cc992cef86740;hp=4a8699fb2dfce4468d70b6e2a73889586d61e26d;hb=efdd1e697a15fba09355f3dbcb90d05524080665;hpb=6f1475b6fcd3e3728d800e622ab7a22265fb8ca4 diff --git a/src/tt.h b/src/tt.h index 4a8699fb..272e752b 100644 --- a/src/tt.h +++ b/src/tt.h @@ -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) 2008-2009 Marco Costalba + Copyright (C) 2008-2010 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 @@ -72,7 +72,21 @@ private: int16_t depth_; }; -/// The transposition table class. This is basically just a huge array + +/// This is the number of TTEntry slots for each position +const int ClusterSize = 5; + +/// Each group of ClusterSize number of TTEntry form a TTCluster +/// that is indexed by a single position key. Cluster is padded +/// to a cache line size so to guarantee always aligned accesses. + +struct TTCluster { + TTEntry data[ClusterSize]; + char cache_line_padding[64 - sizeof(TTEntry[ClusterSize])]; +}; + + +/// The transposition table class. This is basically just a huge array /// containing TTEntry objects, and a few methods for writing new entries /// and reading new ones. @@ -81,27 +95,30 @@ class TranspositionTable { public: TranspositionTable(); ~TranspositionTable(); - void set_size(unsigned mbSize); + void set_size(size_t mbSize); void clear(); void store(const Key posKey, Value v, ValueType type, Depth d, Move m); TTEntry* retrieve(const Key posKey) const; + void prefetch(const Key posKey) const; void new_search(); void insert_pv(const Position& pos, Move pv[]); - void extract_pv(const Position& pos, Move pv[]); + void extract_pv(const Position& pos, Move pv[], const int PLY_MAX); int full() const; private: inline TTEntry* first_entry(const Key posKey) const; - // Be sure 'writes' is at least one cacheline away + // Be sure 'writes' is at least one cache line away // from read only variables. unsigned char pad_before[64 - sizeof(unsigned)]; unsigned writes; // heavy SMP read/write access here unsigned char pad_after[64]; - unsigned size; - TTEntry* entries; + size_t size; + TTCluster* entries; uint8_t generation; }; +extern TranspositionTable TT; + #endif // !defined(TT_H_INCLUDED)