From 6596f0eac0c1d25a12bfd923907bfc78beedbc90 Mon Sep 17 00:00:00 2001 From: protonspring Date: Fri, 3 Apr 2020 15:10:50 -0600 Subject: [PATCH] Always remember the ttMove In master, if the received ttMove meets the prescribed conditions in the various MovePicker constructors, it is returned as the first move, otherwise we set it to MOVE_NONE. If set to MOVE_NONE, we no longer track what the ttMove was, and it will might be returned later in a list of generated moves. This may be a waste. With this patch, if the ttMove fails to meet the prescribed conditions, we simply skip the TT stages, but still store the move and make sure it's never returned. STC LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 66424 W: 12903 L: 12806 D: 40715 Ptnml(0-2): 1195, 7730, 15230, 7897, 1160 LTC LLR: 2.94 (-2.94,2.94) {-1.50,0.50} Total: 45682 W: 5989 L: 5926 D: 33767 Ptnml(0-2): 329, 4361, 13443, 4334, 374 closes https://github.com/official-stockfish/Stockfish/pull/2616 Bench 4928928 --- src/movepick.cpp | 28 +++++++++++----------------- 1 file changed, 11 insertions(+), 17 deletions(-) diff --git a/src/movepick.cpp b/src/movepick.cpp index 580c6d75..b1e10587 100644 --- a/src/movepick.cpp +++ b/src/movepick.cpp @@ -59,42 +59,36 @@ namespace { MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHistory* mh, const LowPlyHistory* lp, const CapturePieceToHistory* cph, const PieceToHistory** ch, Move cm, Move* killers, int pl) : pos(p), mainHistory(mh), lowPlyHistory(lp), captureHistory(cph), continuationHistory(ch), - refutations{{killers[0], 0}, {killers[1], 0}, {cm, 0}}, depth(d), ply(pl) { + ttMove(ttm), refutations{{killers[0], 0}, {killers[1], 0}, {cm, 0}}, depth(d), ply(pl) { assert(d > 0); - stage = pos.checkers() ? EVASION_TT : MAIN_TT; - ttMove = ttm && pos.pseudo_legal(ttm) ? ttm : MOVE_NONE; - stage += (ttMove == MOVE_NONE); + stage = (pos.checkers() ? EVASION_TT : MAIN_TT) + + !(ttm && pos.pseudo_legal(ttm)); } /// MovePicker constructor for quiescence search MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHistory* mh, const CapturePieceToHistory* cph, const PieceToHistory** ch, Square rs) - : pos(p), mainHistory(mh), captureHistory(cph), continuationHistory(ch), recaptureSquare(rs), depth(d) { + : pos(p), mainHistory(mh), captureHistory(cph), continuationHistory(ch), ttMove(ttm), recaptureSquare(rs), depth(d) { assert(d <= 0); - stage = pos.checkers() ? EVASION_TT : QSEARCH_TT; - ttMove = ttm - && (depth > DEPTH_QS_RECAPTURES || to_sq(ttm) == recaptureSquare) - && pos.pseudo_legal(ttm) ? ttm : MOVE_NONE; - stage += (ttMove == MOVE_NONE); + stage = (pos.checkers() ? EVASION_TT : QSEARCH_TT) + + !(ttm && (depth > DEPTH_QS_RECAPTURES || to_sq(ttm) == recaptureSquare) + && pos.pseudo_legal(ttm)); } /// MovePicker constructor for ProbCut: we generate captures with SEE greater /// than or equal to the given threshold. MovePicker::MovePicker(const Position& p, Move ttm, Value th, const CapturePieceToHistory* cph) - : pos(p), captureHistory(cph), threshold(th) { + : pos(p), captureHistory(cph), ttMove(ttm), threshold(th) { assert(!pos.checkers()); - stage = PROBCUT_TT; - ttMove = ttm - && pos.capture(ttm) - && pos.pseudo_legal(ttm) - && pos.see_ge(ttm, threshold) ? ttm : MOVE_NONE; - stage += (ttMove == MOVE_NONE); + stage = PROBCUT_TT + !(ttm && pos.capture(ttm) + && pos.pseudo_legal(ttm) + && pos.see_ge(ttm, threshold)); } /// MovePicker::score() assigns a numerical value to each move in a list, used -- 2.39.2