/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008 Marco Costalba
+ Copyright (C) 2008-2012 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
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-
#if !defined(TT_H_INCLUDED)
#define TT_H_INCLUDED
-////
-//// Includes
-////
-
-#include "depth.h"
-#include "position.h"
-#include "value.h"
+#include <iostream>
+#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 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 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 statV, Value statM) {
+
+ key32 = (uint32_t)k;
+ move16 = (uint16_t)m;
+ bound = (uint8_t)b;
+ 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; }
+ 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; }
private:
- Key key_;
- uint32_t data;
- int16_t value_;
- int16_t depth_;
+ uint32_t key32;
+ uint16_t move16;
+ uint8_t bound, generation8;
+ int16_t value16, depth16, staticValue, staticMargin;
};
-/// 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.
+
+/// 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.
class TranspositionTable {
+ TranspositionTable(const TranspositionTable&);
+ TranspositionTable& operator=(const TranspositionTable&);
+
public:
- TranspositionTable(unsigned mbSize);
+ TranspositionTable();
~TranspositionTable();
- void set_size(unsigned mbSize);
+ void set_size(size_t mbSize);
void clear();
- void store(const Position &pos, Value v, Depth d, Move m, ValueType type);
- TTEntry* retrieve(const Position &pos) const;
+ 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();
- void insert_pv(const Position &pos, Move pv[]);
- int full();
+ TTEntry* first_entry(const Key posKey) const;
+ void refresh(const TTEntry* tte) const;
private:
- inline TTEntry* first_entry(const Position &pos) const;
-
- unsigned size;
- int writes;
- TTEntry* entries;
- uint8_t generation;
+ size_t size;
+ TTCluster* entries;
+ uint8_t generation; // Size must be not bigger then TTEntry::generation8
};
+extern TranspositionTable TT;
+
+
+/// 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.
-////
-//// Constants and variables
-////
+inline TTEntry* TranspositionTable::first_entry(const Key posKey) const {
-// Default transposition table size, in megabytes:
-const int TTDefaultSize = 32;
+ 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.
+
+inline void TranspositionTable::refresh(const TTEntry* tte) const {
+
+ 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)
projects / stockfish / blobdiff