X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.cpp;h=c0809f2805f39c211bb9aba6f70cf7aa051dbf55;hp=33c65670ffe10afd9c738b1ddf5ac4e9f95f687c;hb=cad300c;hpb=c769d4df84f0d4f6290956250c28460b66d95eeb diff --git a/src/movepick.cpp b/src/movepick.cpp index 33c65670..c0809f28 100644 --- a/src/movepick.cpp +++ b/src/movepick.cpp @@ -2,7 +2,7 @@ Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad - Copyright (C) 2015-2017 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad + Copyright (C) 2015-2018 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -25,12 +25,10 @@ namespace { enum Stages { - MAIN_SEARCH, CAPTURES_INIT, GOOD_CAPTURES, KILLERS, COUNTERMOVE, QUIET_INIT, QUIET, BAD_CAPTURES, + MAIN_SEARCH, CAPTURES_INIT, GOOD_CAPTURES, KILLER0, KILLER1, COUNTERMOVE, QUIET_INIT, QUIET, BAD_CAPTURES, EVASION, EVASIONS_INIT, ALL_EVASIONS, - PROBCUT, PROBCUT_INIT, PROBCUT_CAPTURES, - QSEARCH_WITH_CHECKS, QCAPTURES_1_INIT, QCAPTURES_1, QCHECKS, - QSEARCH_NO_CHECKS, QCAPTURES_2_INIT, QCAPTURES_2, - QSEARCH_RECAPTURES, QRECAPTURES + PROBCUT, PROBCUT_CAPTURES_INIT, PROBCUT_CAPTURES, + QSEARCH, QCAPTURES_INIT, QCAPTURES, QCHECKS }; // partial_insertion_sort() sorts moves in descending order up to and including @@ -81,27 +79,14 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHist /// MovePicker constructor for quiescence search MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHistory* mh, const CapturePieceToHistory* cph, Square s) - : pos(p), mainHistory(mh), captureHistory(cph) { + : pos(p), mainHistory(mh), captureHistory(cph), recaptureSquare(s), depth(d) { assert(d <= DEPTH_ZERO); - if (pos.checkers()) - stage = EVASION; - - else if (d > DEPTH_QS_NO_CHECKS) - stage = QSEARCH_WITH_CHECKS; - - else if (d > DEPTH_QS_RECAPTURES) - stage = QSEARCH_NO_CHECKS; - - else - { - stage = QSEARCH_RECAPTURES; - recaptureSquare = s; - return; - } - - ttMove = ttm && pos.pseudo_legal(ttm) ? ttm : MOVE_NONE; + stage = pos.checkers() ? EVASION : QSEARCH; + ttMove = ttm + && pos.pseudo_legal(ttm) + && (depth > DEPTH_QS_RECAPTURES || to_sq(ttm) == recaptureSquare) ? ttm : MOVE_NONE; stage += (ttMove == MOVE_NONE); } @@ -117,7 +102,6 @@ MovePicker::MovePicker(const Position& p, Move ttm, Value th, const CapturePiece && pos.pseudo_legal(ttm) && pos.capture(ttm) && pos.see_ge(ttm, threshold) ? ttm : MOVE_NONE; - stage += (ttMove == MOVE_NONE); } @@ -132,7 +116,7 @@ void MovePicker::score() { for (auto& m : *this) if (Type == CAPTURES) m.value = PieceValue[MG][pos.piece_on(to_sq(m))] - + Value((*captureHistory)[pos.moved_piece(m)][to_sq(m)][type_of(pos.piece_on(to_sq(m)))]); + + (*captureHistory)[pos.moved_piece(m)][to_sq(m)][type_of(pos.piece_on(to_sq(m)))]; else if (Type == QUIETS) m.value = (*mainHistory)[pos.side_to_move()][from_to(m)] @@ -161,17 +145,20 @@ Move MovePicker::next_move(bool skipQuiets) { switch (stage) { - case MAIN_SEARCH: case EVASION: case QSEARCH_WITH_CHECKS: - case QSEARCH_NO_CHECKS: case PROBCUT: + case MAIN_SEARCH: case EVASION: case QSEARCH: case PROBCUT: ++stage; return ttMove; case CAPTURES_INIT: + case PROBCUT_CAPTURES_INIT: + case QCAPTURES_INIT: endBadCaptures = cur = moves; endMoves = generate(pos, cur); score(); ++stage; - /* fallthrough */ + + // Rebranch at the top of the switch via a recursive call + return next_move(skipQuiets); case GOOD_CAPTURES: while (cur < endMoves) @@ -179,36 +166,27 @@ Move MovePicker::next_move(bool skipQuiets) { move = pick_best(cur++, endMoves); if (move != ttMove) { - if (pos.see_ge(move)) - return move; - - if ( type_of(pos.piece_on(to_sq(move))) == KNIGHT - && type_of(pos.moved_piece(move)) == BISHOP - && (cur-1)->value > 1090) + if (pos.see_ge(move, Value(-55 * (cur-1)->value / 1024))) return move; // Losing capture, move it to the beginning of the array *endBadCaptures++ = move; } } - ++stage; - move = killers[0]; // First killer move - if ( move != MOVE_NONE - && move != ttMove - && pos.pseudo_legal(move) - && !pos.capture(move)) - return move; /* fallthrough */ - case KILLERS: - ++stage; - move = killers[1]; // Second killer move - if ( move != MOVE_NONE - && move != ttMove - && pos.pseudo_legal(move) - && !pos.capture(move)) - return move; + case KILLER0: + case KILLER1: + do + { + move = killers[++stage - KILLER1]; + if ( move != MOVE_NONE + && move != ttMove + && pos.pseudo_legal(move) + && !pos.capture(move)) + return move; + } while (stage <= KILLER1); /* fallthrough */ case COUNTERMOVE: @@ -232,17 +210,16 @@ Move MovePicker::next_move(bool skipQuiets) { /* fallthrough */ case QUIET: - while ( cur < endMoves - && (!skipQuiets || cur->value >= VALUE_ZERO)) - { - move = *cur++; - - if ( move != ttMove - && move != killers[0] - && move != killers[1] - && move != countermove) - return move; - } + if (!skipQuiets) + while (cur < endMoves) + { + move = *cur++; + if ( move != ttMove + && move != killers[0] + && move != killers[1] + && move != countermove) + return move; + } ++stage; cur = moves; // Point to beginning of bad captures /* fallthrough */ @@ -268,13 +245,6 @@ Move MovePicker::next_move(bool skipQuiets) { } break; - case PROBCUT_INIT: - cur = moves; - endMoves = generate(pos, cur); - score(); - ++stage; - /* fallthrough */ - case PROBCUT_CAPTURES: while (cur < endMoves) { @@ -285,21 +255,15 @@ Move MovePicker::next_move(bool skipQuiets) { } break; - case QCAPTURES_1_INIT: case QCAPTURES_2_INIT: - cur = moves; - endMoves = generate(pos, cur); - score(); - ++stage; - /* fallthrough */ - - case QCAPTURES_1: case QCAPTURES_2: + case QCAPTURES: while (cur < endMoves) { move = pick_best(cur++, endMoves); - if (move != ttMove) + if ( move != ttMove + && (depth > DEPTH_QS_RECAPTURES || to_sq(move) == recaptureSquare)) return move; } - if (stage == QCAPTURES_2) + if (depth <= DEPTH_QS_NO_CHECKS) break; cur = moves; endMoves = generate(pos, cur); @@ -309,28 +273,12 @@ Move MovePicker::next_move(bool skipQuiets) { case QCHECKS: while (cur < endMoves) { - move = cur++->move; + move = *cur++; if (move != ttMove) return move; } break; - case QSEARCH_RECAPTURES: - cur = moves; - endMoves = generate(pos, cur); - score(); - ++stage; - /* fallthrough */ - - case QRECAPTURES: - while (cur < endMoves) - { - move = pick_best(cur++, endMoves); - if (to_sq(move) == recaptureSquare) - return move; - } - break; - default: assert(false); }