/*
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 {
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;
void store(const Key key, Value v, Bound type, Depth d, Move m, Value statV, Value kingD);
private:
- size_t size;
- TTEntry* entries;
+ uint32_t hashMask;
+ TTEntry* table;
+ void* mem;
uint8_t generation; // Size must be not bigger then TTEntry::generation8
};
inline TTEntry* TranspositionTable::first_entry(const Key key) const {
- return entries + ((uint32_t)key & (size - 1)) * ClusterSize;
+ return table + ((uint32_t)key & hashMask);
}