X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftt.h;h=c7c39e90cc9918d3cddb8611a12d8e66ffbf63a8;hp=bff1749841b1ac1312a7a413d9c3619eb6e461c0;hb=293c44bc09587259818a82e1d2afb511e552badd;hpb=60bc30275decbb00aa26af8dc14ad6cb167eaa82 diff --git a/src/tt.h b/src/tt.h index bff17498..c7c39e90 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) 2008-2013 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 @@ -17,108 +17,109 @@ along with this program. If not, see . */ - #if !defined(TT_H_INCLUDED) #define TT_H_INCLUDED -//// -//// Includes -//// - -#include "depth.h" -#include "position.h" -#include "value.h" - +#include "misc.h" +#include "types.h" -//// -//// Types -//// - -/// The TTEntry class is the class of transposition table entries +/// The TTEntry is the class of transposition table entries /// -/// A TTEntry needs 96 bits to be stored +/// A TTEntry needs 128 bits to be stored /// /// bit 0-31: key /// bit 32-63: data /// bit 64-79: value /// bit 80-95: depth +/// bit 96-111: static value +/// bit 112-127: margin of static value /// /// the 32 bits of the data field are so defined /// -/// bit 0-16: move -/// bit 17-19: not used -/// bit 20-22: value type +/// bit 0-15: move +/// bit 16-20: not used +/// bit 21-22: value type /// bit 23-31: generation class TTEntry { public: - TTEntry() {} - TTEntry(uint32_t k, Value v, ValueType t, Depth d, Move m, int generation) - : key_ (k), data((m & 0x1FFFF) | (t << 20) | (generation << 23)), - value_(int16_t(v)), depth_(int16_t(d)) {} - - uint32_t key() const { return key_; } - Depth depth() const { return Depth(depth_); } - Move move() const { return Move(data & 0x1FFFF); } - Value value() const { return Value(value_); } - ValueType type() const { return ValueType((data >> 20) & 7); } - int generation() const { return (data >> 23); } + void save(uint32_t k, Value v, Bound b, Depth d, Move m, int g, Value ev, Value em) { + + key32 = (uint32_t)k; + move16 = (uint16_t)m; + bound = (uint8_t)b; + generation8 = (uint8_t)g; + value16 = (int16_t)v; + depth16 = (int16_t)d; + evalValue = (int16_t)ev; + evalMargin = (int16_t)em; + } + void set_generation(int g) { generation8 = (uint8_t)g; } + + uint32_t key() const { return key32; } + Depth depth() const { return (Depth)depth16; } + Move move() const { return (Move)move16; } + Value value() const { return (Value)value16; } + Bound type() const { return (Bound)bound; } + int generation() const { return (int)generation8; } + Value eval_value() const { return (Value)evalValue; } + Value eval_margin() const { return (Value)evalMargin; } private: - uint32_t key_; - uint32_t data; - int16_t value_; - int16_t depth_; + uint32_t key32; + uint16_t move16; + uint8_t bound, generation8; + int16_t value16, depth16, evalValue, evalMargin; }; -/// This is the number of TTEntry slots for each position -const int ClusterSize = 5; +/// A TranspositionTable consists of a power of 2 number of clusters and each +/// cluster consists of ClusterSize number of TTEntry. Each non-empty entry +/// contains information of exactly one position. Size of a cluster shall not be +/// bigger than a cache line size. In case it is less, it should be padded to +/// guarantee always aligned accesses. + +class TranspositionTable { + + static const unsigned ClusterSize = 4; // A cluster is 64 Bytes -/// 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. +public: + ~TranspositionTable() { delete [] table; } + void new_search() { generation++; } + + TTEntry* probe(const Key key) const; + TTEntry* first_entry(const Key key) const; + void refresh(const TTEntry* tte) const; + void set_size(size_t mbSize); + void clear(); + void store(const Key key, Value v, Bound type, Depth d, Move m, Value statV, Value kingD); -struct TTCluster { - TTEntry data[ClusterSize]; - char cache_line_padding[64 - sizeof(TTEntry[ClusterSize])]; +private: + uint32_t hashMask; + TTEntry* table; + uint8_t generation; // Size must be not bigger then TTEntry::generation8 }; +extern TranspositionTable TT; -/// 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. -class TranspositionTable { +/// TranspositionTable::first_entry() returns a pointer to the first entry of +/// a cluster given a position. The lowest order bits of the key are used to +/// get the index of the cluster. -public: - TranspositionTable(); - ~TranspositionTable(); - void set_size(unsigned 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[], int pvSize); - int full() const; +inline TTEntry* TranspositionTable::first_entry(const Key key) const { -private: - inline TTEntry* first_entry(const Key posKey) const; + return table + ((uint32_t)key & hashMask); +} - // 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; - TTCluster* entries; - uint8_t generation; -}; +/// TranspositionTable::refresh() updates the 'generation' value of the TTEntry +/// to avoid aging. Normally called after a TT hit. -extern TranspositionTable TT; +inline void TranspositionTable::refresh(const TTEntry* tte) const { + + const_cast(tte)->set_generation(generation); +} #endif // !defined(TT_H_INCLUDED)