-/// 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 Entry, int HashSize>
-class SimpleHash {
-
- SimpleHash(const SimpleHash&);
- SimpleHash& operator=(const SimpleHash&);
-
-public:
- SimpleHash() {
-
- 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)); }
-
-protected:
- Entry* entries;
-};
-
-
-/// The TTEntry class is the class of transposition table entries
-///
-/// 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
-
-class TTEntry {
-
-public:
- 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:
- uint32_t key32;
- uint16_t move16;
- uint8_t valueType;
- uint8_t generation8;
- int16_t value16;
- int16_t depth16;
- int16_t staticValue;
- int16_t staticMargin;
+namespace Stockfish {
+
+// TTEntry struct is the 10 bytes transposition table entry, defined as below:
+//
+// key 16 bit
+// depth 8 bit
+// generation 5 bit
+// pv node 1 bit
+// bound type 2 bit
+// move 16 bit
+// value 16 bit
+// eval value 16 bit
+struct TTEntry {
+
+ Move move() const { return Move(move16); }
+ Value value() const { return Value(value16); }
+ Value eval() const { return Value(eval16); }
+ Depth depth() const { return Depth(depth8 + DEPTH_OFFSET); }
+ bool is_pv() const { return bool(genBound8 & 0x4); }
+ Bound bound() const { return Bound(genBound8 & 0x3); }
+ void save(Key k, Value v, bool pv, Bound b, Depth d, Move m, Value ev);
+
+ private:
+ friend class TranspositionTable;
+
+ uint16_t key16;
+ uint8_t depth8;
+ uint8_t genBound8;
+ uint16_t move16;
+ int16_t value16;
+ int16_t eval16;