X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.cpp;h=4f2fa01eb231ba64e10feaba33d1af33977a35be;hp=f43def4d36fd51fd4f573c470a8866195890b531;hb=49e110c52b19f5c99954d4797b8e991b0b60007c;hpb=99e547f4cb190e462d0c582b731a0fcf25ce1545 diff --git a/src/movepick.cpp b/src/movepick.cpp index f43def4d..4f2fa01e 100644 --- a/src/movepick.cpp +++ b/src/movepick.cpp @@ -25,7 +25,7 @@ namespace { - enum Sequencer { + enum Stages { MAIN_SEARCH, CAPTURES_S1, KILLERS_S1, QUIETS_1_S1, QUIETS_2_S1, BAD_CAPTURES_S1, EVASION, EVASIONS_S2, QSEARCH_0, CAPTURES_S3, QUIET_CHECKS_S3, @@ -70,32 +70,21 @@ namespace { /// search captures, promotions and some checks) and about how important good /// move ordering is at the current node. -MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h, Move* cm, - Search::Stack* s, Value beta) : pos(p), history(h), depth(d) { +MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& h, + Move* cm, Search::Stack* s) : pos(p), history(h), depth(d) { assert(d > DEPTH_ZERO); - captureThreshold = 0; cur = end = moves; endBadCaptures = moves + MAX_MOVES - 1; countermoves = cm; ss = s; if (p.checkers()) - phase = EVASION; + stage = EVASION; else - { - phase = MAIN_SEARCH; - - // Consider sligtly negative captures as good if at low depth and far from beta - if (ss->staticEval < beta - PawnValueMg && d < 3 * ONE_PLY) - captureThreshold = -PawnValueMg; - - // Consider negative captures as good if still enough to reach beta - else if (ss->staticEval > beta) - captureThreshold = beta - ss->staticEval; - } + stage = MAIN_SEARCH; ttMove = (ttm && pos.is_pseudo_legal(ttm) ? ttm : MOVE_NONE); end += (ttMove != MOVE_NONE); @@ -107,14 +96,14 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& assert(d <= DEPTH_ZERO); if (p.checkers()) - phase = EVASION; + stage = EVASION; else if (d > DEPTH_QS_NO_CHECKS) - phase = QSEARCH_0; + stage = QSEARCH_0; else if (d > DEPTH_QS_RECAPTURES) { - phase = QSEARCH_1; + stage = QSEARCH_1; // Skip TT move if is not a capture or a promotion, this avoids qsearch // tree explosion due to a possible perpetual check or similar rare cases @@ -124,7 +113,7 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const HistoryStats& } else { - phase = RECAPTURE; + stage = RECAPTURE; recaptureSquare = sq; ttm = MOVE_NONE; } @@ -138,7 +127,7 @@ MovePicker::MovePicker(const Position& p, Move ttm, const HistoryStats& h, Piece assert(!pos.checkers()); - phase = PROBCUT; + stage = PROBCUT; // In ProbCut we generate only captures better than parent's captured piece captureThreshold = PieceValue[MG][pt]; @@ -226,7 +215,7 @@ void MovePicker::generate_next() { cur = moves; - switch (++phase) { + switch (++stage) { case CAPTURES_S1: case CAPTURES_S3: case CAPTURES_S4: case CAPTURES_S5: case CAPTURES_S6: end = generate(pos, moves); @@ -282,7 +271,7 @@ void MovePicker::generate_next() { return; case EVASION: case QSEARCH_0: case QSEARCH_1: case PROBCUT: case RECAPTURE: - phase = STOP; + stage = STOP; case STOP: end = cur + 1; // Avoid another next_phase() call return; @@ -307,7 +296,7 @@ Move MovePicker::next_move() { while (cur == end) generate_next(); - switch (phase) { + switch (stage) { case MAIN_SEARCH: case EVASION: case QSEARCH_0: case QSEARCH_1: case PROBCUT: cur++; @@ -317,9 +306,7 @@ Move MovePicker::next_move() { move = pick_best(cur++, end)->move; if (move != ttMove) { - assert(captureThreshold <= 0); // Otherwise we cannot use see_sign() - - if (pos.see_sign(move) >= captureThreshold) + if (pos.see_sign(move) >= 0) return move; // Losing capture, move it to the tail of the array