Value value_to_tt(Value v, int ply);
Value value_from_tt(Value v, int ply);
void update_pv(Move* pv, Move move, Move* childPv);
- void update_stats(const Position& pos, Stack* ss, Move move, Depth depth, Move* quiets, int quietsCnt);
+ void update_stats(const Position& pos, Stack* ss, Move move, Move* quiets, int quietsCnt, Value bonus);
+ void update_opponent_stats(const Position& pos, Stack* ss, Value bonus);
void check_time();
} // namespace
// If ttMove is quiet, update killers, history, counter move on TT hit
if (ttValue >= beta && ttMove)
- update_stats(pos, ss, ttMove, depth, nullptr, 0);
+ {
+ int d = depth / ONE_PLY;
+ if (!pos.capture_or_promotion(ttMove))
+ {
+ Value bonus = Value(d * d + 2 * d - 2);
+ update_stats(pos, ss, ttMove, nullptr, 0, bonus);
+ }
+
+ // Extra penalty for a quiet TT move in previous ply when it gets refuted
+ if ((ss-1)->moveCount == 1 && !pos.captured_piece_type())
+ {
+ Value penalty = Value(d * d + 4 * d + 1);
+ update_opponent_stats(pos, ss, -penalty);
+ }
+ }
return ttValue;
}
if (!moveCount)
bestValue = excludedMove ? alpha
: inCheck ? mated_in(ss->ply) : DrawValue[pos.side_to_move()];
-
- // Quiet best move: update killers, history and countermoves
else if (bestMove)
- update_stats(pos, ss, bestMove, depth, quietsSearched, quietCount);
+ {
+ int d = depth / ONE_PLY;
+ // Quiet best move: update killers, history and countermoves
+ if (!pos.capture_or_promotion(bestMove))
+ {
+ Value bonus = Value(d * d + 2 * d - 2);
+ update_stats(pos, ss, bestMove, quietsSearched, quietCount, bonus);
+ }
+
+ // Extra penalty for a quiet TT move in previous ply when it gets refuted
+ if ((ss-1)->moveCount == 1 && !pos.captured_piece_type())
+ {
+ Value penalty = Value(d * d + 4 * d + 1);
+ update_opponent_stats(pos, ss, -penalty);
+ }
+ }
// Bonus for prior countermove that caused the fail low
else if ( depth >= 3 * ONE_PLY
&& !pos.captured_piece_type()
&& is_ok((ss-1)->currentMove))
{
- Square prevSq = to_sq((ss-1)->currentMove);
- Value bonus = Value((depth / ONE_PLY) * (depth / ONE_PLY) + 2 * depth / ONE_PLY - 2);
- if ((ss-2)->counterMoves)
- (ss-2)->counterMoves->update(pos.piece_on(prevSq), prevSq, bonus);
-
- if ((ss-3)->counterMoves)
- (ss-3)->counterMoves->update(pos.piece_on(prevSq), prevSq, bonus);
-
- if ((ss-5)->counterMoves)
- (ss-5)->counterMoves->update(pos.piece_on(prevSq), prevSq, bonus);
+ int d = depth / ONE_PLY;
+ Value bonus = Value(d * d + 2 * d - 2);
+ update_opponent_stats(pos, ss, bonus);
}
tte->save(posKey, value_to_tt(bestValue, ss->ply),
}
- // update_stats() updates killers, history, countermove and countermove plus
- // follow-up move history when a new quiet best move is found.
+ // update_opponent_stats() updates countermoves for prior opponent move, i.e.
+ // (ss-1)->currentMove. Called for both capture and non-capture moves.
- void update_stats(const Position& pos, Stack* ss, Move move,
- Depth depth, Move* quiets, int quietsCnt) {
+ void update_opponent_stats(const Position& pos, Stack* ss, Value bonus) {
- Value bonus = Value((depth / ONE_PLY) * (depth / ONE_PLY) + 2 * depth / ONE_PLY - 2);
Square prevSq = to_sq((ss-1)->currentMove);
- // Extra penalty for a quiet TT move in previous ply when it gets refuted
- if ((ss-1)->moveCount == 1 && !pos.captured_piece_type())
- {
- CounterMoveStats* fmh = (ss-2)->counterMoves;
- CounterMoveStats* cmh2 = (ss-3)->counterMoves;
- CounterMoveStats* cmh3 = (ss-5)->counterMoves;
+ CounterMoveStats* cmh = (ss-2)->counterMoves;
+ CounterMoveStats* fmh1 = (ss-3)->counterMoves;
+ CounterMoveStats* fmh2 = (ss-5)->counterMoves;
- if (fmh)
- fmh->update(pos.piece_on(prevSq), prevSq, -bonus - 2 * (depth + 1) / ONE_PLY - 1);
+ if (cmh)
+ cmh->update(pos.piece_on(prevSq), prevSq, bonus);
- if (cmh2)
- cmh2->update(pos.piece_on(prevSq), prevSq, -bonus - 2 * (depth + 1) / ONE_PLY - 1);
+ if (fmh1)
+ fmh1->update(pos.piece_on(prevSq), prevSq, bonus);
- if (cmh3)
- cmh3->update(pos.piece_on(prevSq), prevSq, -bonus - 2 * (depth + 1) / ONE_PLY - 1);
- }
+ if (fmh2)
+ fmh2->update(pos.piece_on(prevSq), prevSq, bonus);
+ }
- if (pos.capture_or_promotion(move))
- return;
+
+ // update_stats() updates killers, history, countermove and countermove plus
+ // follow-up move history when a new quiet best move is found.
+
+ void update_stats(const Position& pos, Stack* ss, Move move,
+ Move* quiets, int quietsCnt, Value bonus) {
if (ss->killers[0] != move)
{
}
CounterMoveStats* cmh = (ss-1)->counterMoves;
- CounterMoveStats* fmh = (ss-2)->counterMoves;
+ CounterMoveStats* fmh1 = (ss-2)->counterMoves;
CounterMoveStats* fmh2 = (ss-4)->counterMoves;
+
Color c = pos.side_to_move();
Thread* thisThread = pos.this_thread();
-
thisThread->history.update(pos.moved_piece(move), to_sq(move), bonus);
thisThread->fromTo.update(c, move, bonus);
if (cmh)
{
+ Square prevSq = to_sq((ss-1)->currentMove);
thisThread->counterMoves.update(pos.piece_on(prevSq), prevSq, move);
cmh->update(pos.moved_piece(move), to_sq(move), bonus);
}
- if (fmh)
- fmh->update(pos.moved_piece(move), to_sq(move), bonus);
+ if (fmh1)
+ fmh1->update(pos.moved_piece(move), to_sq(move), bonus);
if (fmh2)
fmh2->update(pos.moved_piece(move), to_sq(move), bonus);
if (cmh)
cmh->update(pos.moved_piece(quiets[i]), to_sq(quiets[i]), -bonus);
- if (fmh)
- fmh->update(pos.moved_piece(quiets[i]), to_sq(quiets[i]), -bonus);
+ if (fmh1)
+ fmh1->update(pos.moved_piece(quiets[i]), to_sq(quiets[i]), -bonus);
if (fmh2)
fmh2->update(pos.moved_piece(quiets[i]), to_sq(quiets[i]), -bonus);