void
TranspositionTable::extractPVMoves(const Position& rootPos, const Move& mFirst, std::vector<Move>& pv) {
Position pos(rootPos);
Move m(mFirst);
UndoInfo ui;
std::vector<U64> hashHistory;
while (true) {
pv.push_back(m);
pos.makeMove(m, ui);
if (contains(hashHistory, pos.zobristHash()))
break;
hashHistory.push_back(pos.zobristHash());
TTEntry ent;
ent.clear();
probe(pos.historyHash(), ent);
if (ent.getType() == TType::T_EMPTY)
break;
ent.getMove(m);
MoveList moves;
MoveGen::pseudoLegalMoves(pos, moves);
MoveGen::removeIllegal(pos, moves);
bool contains = false;
for (int mi = 0; mi < moves.size; mi++)
if (moves[mi].equals(m)) {
contains = true;
break;
}
if (!contains)
break;
}
}
/** Extract the PV starting from posIn, using hash entries, both exact scores and bounds. */
std::string
TranspositionTable::extractPV(const Position& posIn) {
std::string ret;
Position pos(posIn);
bool first = true;
TTEntry ent;
ent.clear();
probe(pos.historyHash(), ent);
UndoInfo ui;
std::vector<U64> hashHistory;
bool repetition = false;
while (ent.getType() != TType::T_EMPTY) {
Move m;
ent.getMove(m);
MoveList moves;
MoveGen::pseudoLegalMoves(pos, moves);
MoveGen::removeIllegal(pos, moves);
bool valid = false;
for (int mi = 0; mi < moves.size; mi++)
if (moves[mi].equals(m)) {
valid = true;
break;
}
if (!valid)
break;
if (repetition)
break;
if (!first)
ret += ' ';
if (ent.getType() == TType::T_LE)
ret += '<';
else if (ent.getType() == TType::T_GE)
ret += '>';
std::string moveStr = TextIO::moveToString(pos, m, false);
ret += moveStr;
pos.makeMove(m, ui);
if (contains(hashHistory, pos.zobristHash()))
repetition = true;
hashHistory.push_back(pos.zobristHash());
probe(pos.historyHash(), ent);
first = false;
}
return ret;
}
