-/// TranspositionTable::store() writes a new entry containing position key and
-/// valuable information of current position. The lowest order bits of position
-/// key are used to decide in which cluster the position will be placed.
-/// When a new entry is written and there are no empty entries available in the
-/// cluster, it replaces the least valuable of the entries. A TTEntry t1 is considered
-/// to be more valuable than a TTEntry t2 if t1 is from the current search and t2
-/// is from a previous search, or if the depth of t1 is bigger than the depth of t2.
+ // Find an entry to be replaced according to the replacement strategy
+ TTEntry* replace = tte;
+ for (int i = 1; i < ClusterSize; ++i)
+ // Due to our packed storage format for generation and its cyclic
+ // nature we add 259 (256 is the modulus plus 3 to keep the lowest
+ // two bound bits from affecting the result) to calculate the entry
+ // age correctly even after generation8 overflows into the next cycle.
+ if ( replace->depth8 - ((259 + generation8 - replace->genBound8) & 0xFC) * 2
+ > tte[i].depth8 - ((259 + generation8 - tte[i].genBound8) & 0xFC) * 2)
+ replace = &tte[i];
+
+ return found = false, replace;
+}