From 3e739f883fb766f965ed434507c9c8fbcf18a855 Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Wed, 24 Aug 2016 16:52:05 +0200 Subject: [PATCH] Reformat stats update Rewritten in a way to have explicit in the search the bonus/penalty we apply: hopefully this will lead to further simplification/fix of current rather messy stats update code. No functional change. --- src/search.cpp | 103 +++++++++++++++++++++++++++++-------------------- 1 file changed, 62 insertions(+), 41 deletions(-) diff --git a/src/search.cpp b/src/search.cpp index 15f08859..0358cd24 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -168,7 +168,8 @@ namespace { 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 @@ -637,8 +638,22 @@ 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; } @@ -1111,26 +1126,32 @@ moves_loop: // When in check search starts from here 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), @@ -1390,34 +1411,33 @@ moves_loop: // When in check search starts from here } - // 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) { @@ -1426,22 +1446,23 @@ moves_loop: // When in check search starts from here } 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); @@ -1455,8 +1476,8 @@ moves_loop: // When in check search starts from here 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); -- 2.39.2