X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftt.h;h=fe4cee62ae39a83ec94ad3d232289daa94a7d395;hp=08121f66f699a9bcf7e6b1e54893b0636f75f80b;hb=2f1935078da225c90f7887ed8c345cc7baebcfcc;hpb=2fff532f4e80c8e2e61d8b3955447f13124d40f0 diff --git a/src/tt.h b/src/tt.h index 08121f66..fe4cee62 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 @@ -17,91 +17,159 @@ along with this program. If not, see . */ - #if !defined(TT_H_INCLUDED) #define TT_H_INCLUDED -//// -//// Includes -//// +#include + +#include "move.h" +#include "types.h" + +/// A simple fixed size hash table used to store pawns and material +/// configurations. It is basically just an array of Entry objects. +/// Without cluster concept or overwrite policy. + +template +class SimpleHash { + + SimpleHash(const SimpleHash&); + SimpleHash& operator=(const SimpleHash&); + +public: + SimpleHash() { -#include "depth.h" -#include "position.h" -#include "value.h" + entries = new (std::nothrow) Entry[HashSize]; + if (!entries) + { + std::cerr << "Failed to allocate " << HashSize * sizeof(Entry) + << " bytes for material hash table." << std::endl; + exit(EXIT_FAILURE); + } + memset(entries, 0, HashSize * sizeof(Entry)); + } + virtual ~SimpleHash() { delete [] entries; } + + Entry* find(Key key) const { return entries + ((uint32_t)key & (HashSize - 1)); } + void prefetch(Key key) const { ::prefetch((char*)find(key)); } + +protected: + Entry* entries; +}; -//// -//// Types -//// /// The TTEntry class is the class of transposition table entries /// /// A TTEntry needs 128 bits to be stored /// -/// bit 0-63: key -/// bit 64-95: data -/// bit 96-111: value -/// bit 112-127: depth +/// 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(Key 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)) {} - - Key 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, ValueType t, Depth d, Move m, int g, Value statV, Value statM) { + + key32 = (uint32_t)k; + move16 = (uint16_t)m; + valueType = (uint8_t)t; + generation8 = (uint8_t)g; + value16 = (int16_t)v; + depth16 = (int16_t)d; + staticValue = (int16_t)statV; + staticMargin = (int16_t)statM; + } + 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); } + ValueType type() const { return ValueType(valueType); } + int generation() const { return generation8; } + Value static_value() const { return Value(staticValue); } + Value static_value_margin() const { return Value(staticMargin); } private: - Key key_; - uint32_t data; - int16_t value_; - int16_t depth_; + uint32_t key32; + uint16_t move16; + uint8_t valueType; + uint8_t generation8; + int16_t value16; + int16_t depth16; + int16_t staticValue; + int16_t staticMargin; +}; + + +/// This is the number of TTEntry slots for each cluster +const int ClusterSize = 4; + +/// TTCluster consists of ClusterSize number of TTEntries. +/// Size of TTCluster must not be bigger than a cache line size. +/// In case it is less, it should be padded to guarantee always aligned accesses. + +struct TTCluster { + TTEntry data[ClusterSize]; }; -/// The transposition table class. This is basically just a huge array -/// containing TTEntry objects, and a few methods for writing new entries + +/// The transposition table class. This is basically just a huge array +/// containing TTCluster objects, and a few methods for writing new entries /// and reading new ones. class TranspositionTable { + TranspositionTable(const TranspositionTable&); + TranspositionTable& operator=(const 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); + void store(const Key posKey, Value v, ValueType type, Depth d, Move m, Value statV, Value kingD); TTEntry* retrieve(const Key posKey) const; void new_search(); - void insert_pv(const Position& pos, Move pv[]); - void extract_pv(const Position& pos, Move pv[]); - int full() const; + TTEntry* first_entry(const Key posKey) const; + void refresh(const TTEntry* tte) const; private: - inline TTEntry* first_entry(const Key posKey) const; + size_t size; + TTCluster* entries; + uint8_t generation; // To properly compare, size must be smaller then TT stored value +}; - // Be sure 'writes' is at least one cacheline 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]; +extern TranspositionTable TT; - unsigned size; - TTEntry* entries; - uint8_t generation; -}; + +/// 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. + +inline TTEntry* TranspositionTable::first_entry(const Key posKey) const { + + return entries[((uint32_t)posKey) & (size - 1)].data; +} + + +/// TranspositionTable::refresh updates the 'generation' value of the TTEntry +/// to avoid aging. Normally called after a TT hit, before to return. + +inline void TranspositionTable::refresh(const TTEntry* tte) const { + + const_cast(tte)->set_generation(generation); +} #endif // !defined(TT_H_INCLUDED)