- // Transposition table lookup
- const TTEntry* tte = TT.retrieve(pos);
- if (tte && ok_to_use_TT(tte, depth, beta, ply))
- return value_from_tt(tte->value(), ply);
+ // Transposition table lookup, only when not in PV
+ bool pvNode = (beta - alpha != 1);
+ if (!pvNode)
+ {
+ const TTEntry* tte = TT.retrieve(pos);
+ if (tte && ok_to_use_TT(tte, depth, beta, ply))
+ return value_from_tt(tte->value(), ply);
+ }