void save(Key k, Value v, Bound b, Depth d, Move m, Value ev, uint8_t g) {
- if (m || (k >> 48) != key16) // Preserve any existing move for the same position
+ // Preserve any existing move for the same position
+ if (m || (k >> 48) != key16)
move16 = (uint16_t)m;
- key16 = (uint16_t)(k >> 48);
- value16 = (int16_t)v;
- eval16 = (int16_t)ev;
- genBound8 = (uint8_t)(g | b);
- depth8 = (int8_t)d;
+ // Don't overwrite more valuable entries
+ if ( (k >> 48) != key16
+ || d > depth8 - 2
+ || g != (genBound8 & 0xFC)
+ || b == BOUND_EXACT)
+ {
+ key16 = (uint16_t)(k >> 48);
+ value16 = (int16_t)v;
+ eval16 = (int16_t)ev;
+ genBound8 = (uint8_t)(g | b);
+ depth8 = (int8_t)d;
+ }
}
private:
char padding[2]; // Align to the cache line size
};
+ static_assert(sizeof(Cluster) == CacheLineSize / 2, "Cluster size incorrect");
+
public:
~TranspositionTable() { free(mem); }
void new_search() { generation8 += 4; } // Lower 2 bits are used by Bound