/*
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
#include "misc.h"
#include "types.h"
-/// The TTEntry is the class of transposition table entries
+/// The TTEntry is the 128 bit transposition table entry, defined as below:
///
-/// 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 0-15: move
-/// bit 16-20: not used
-/// bit 21-22: value type
-/// bit 23-31: generation
+/// key: 32 bit
+/// move: 16 bit
+/// bound type: 8 bit
+/// generation: 8 bit
+/// value: 16 bit
+/// depth: 16 bit
+/// static value: 16 bit
+/// static margin: 16 bit
-class TTEntry {
+struct TTEntry {
-public:
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;
+ bound8 = (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; }
+ void set_generation(uint8_t g) { generation8 = 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; }
+ Bound bound() const { return (Bound)bound8; }
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;
+ uint8_t bound8, generation8;
int16_t value16, depth16, evalValue, evalMargin;
};
static const unsigned ClusterSize = 4; // A cluster is 64 Bytes
public:
- ~TranspositionTable() { delete [] entries; }
+ ~TranspositionTable() { free(mem); }
void new_search() { generation++; }
- TTEntry* probe(const Key key) const;
+ const 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 store(const Key key, Value v, Bound type, Depth d, Move m, Value statV, Value kingD);
private:
- size_t size;
- TTEntry* entries;
- uint8_t generation; // Size must be not bigger then TTEntry::generation8
+ uint32_t hashMask;
+ TTEntry* table;
+ void* mem;
+ uint8_t generation; // Size must be not bigger than TTEntry::generation8
};
extern TranspositionTable TT;
inline TTEntry* TranspositionTable::first_entry(const Key key) const {
- return entries + ((uint32_t)key & (size - 1)) * ClusterSize;
+ return table + ((uint32_t)key & hashMask);
}