/*
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
#if !defined(TT_H_INCLUDED)
#define TT_H_INCLUDED
-#include <iostream>
-
#include "misc.h"
#include "types.h"
-
/// The TTEntry is the class of transposition table entries
///
/// A TTEntry needs 128 bits to be stored
class TTEntry {
public:
- void save(uint32_t k, Value v, Bound b, Depth d, Move m, int g, Value statV, Value statM) {
+ 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;
generation8 = (uint8_t)g;
value16 = (int16_t)v;
depth16 = (int16_t)d;
- staticValue = (int16_t)statV;
- staticMargin = (int16_t)statM;
+ 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 static_value() const { return (Value)staticValue; }
- Value static_value_margin() const { return (Value)staticMargin; }
+ 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 key32;
uint16_t move16;
uint8_t bound, generation8;
- int16_t value16, depth16, staticValue, staticMargin;
+ int16_t value16, depth16, evalValue, evalMargin;
};
-/// 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
-/// TTCluster objects, and a few methods for writing and reading entries.
+/// 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 {
- TranspositionTable(const TranspositionTable&);
- TranspositionTable& operator=(const TranspositionTable&);
+ static const unsigned ClusterSize = 4; // A cluster is 64 Bytes
public:
- TranspositionTable();
- ~TranspositionTable();
+ ~TranspositionTable() { free(mem); }
+ 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 posKey, Value v, Bound type, Depth d, Move m, Value statV, Value kingD);
- TTEntry* probe(const Key posKey) const;
- void new_search();
- TTEntry* first_entry(const Key posKey) const;
- void refresh(const TTEntry* tte) const;
+ void store(const Key key, Value v, Bound type, Depth d, Move m, Value statV, Value kingD);
private:
- size_t size;
- TTCluster* entries;
+ uint32_t hashMask;
+ TTEntry* table;
+ void* mem;
uint8_t generation; // Size must be not bigger then TTEntry::generation8
};
/// 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 {
+inline TTEntry* TranspositionTable::first_entry(const Key key) const {
- return entries[((uint32_t)posKey) & (size - 1)].data;
+ return table + ((uint32_t)key & hashMask);
}
const_cast<TTEntry*>(tte)->set_generation(generation);
}
-
-/// 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, overwrite policy nor resizing.
-
-template<class Entry, int HashSize>
-struct SimpleHash {
-
- typedef SimpleHash<Entry, HashSize> Base;
-
- SimpleHash() {
-
- entries = new (std::nothrow) Entry[HashSize];
- if (!entries)
- {
- std::cerr << "Failed to allocate " << HashSize * sizeof(Entry)
- << " bytes for hash table." << std::endl;
- ::exit(EXIT_FAILURE);
- }
- memset(entries, 0, HashSize * sizeof(Entry));
- }
-
- virtual ~SimpleHash() { delete [] entries; }
-
- Entry* probe(Key key) const { return entries + ((uint32_t)key & (HashSize - 1)); }
- void prefetch(Key key) const { ::prefetch((char*)probe(key)); }
-
-protected:
- Entry* entries;
-};
-
#endif // !defined(TT_H_INCLUDED)