X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.cpp;h=22845ba2a2a86f3f3cfb86c9ed0428fee21de582;hp=b115e8ffb1a9c3b9a6a1c6371ffef62067eea3e3;hb=bbb24625764619e5886ce0250739a4c9bfdb4d33;hpb=fcc49561a139c6e0ddfbd9fc4942ce415a7963c9 diff --git a/src/movepick.cpp b/src/movepick.cpp index b115e8ff..22845ba2 100644 --- a/src/movepick.cpp +++ b/src/movepick.cpp @@ -1,13 +1,14 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008 Marco Costalba + Copyright (C) 2008-2009 Marco Costalba Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. + Stockfish is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the @@ -22,9 +23,11 @@ //// Includes //// +#include #include #include "history.h" +#include "evaluate.h" #include "movegen.h" #include "movepick.h" #include "search.h" @@ -48,7 +51,6 @@ namespace { } - //// //// Functions //// @@ -61,29 +63,33 @@ namespace { /// search captures, promotions and some checks) and about how important good /// move ordering is at the current node. -MovePicker::MovePicker(const Position& p, bool pvnode, Move ttm, Move mk, - Move k1, Move k2, Depth d) : pos(p) { - pvNode = pvnode; +MovePicker::MovePicker(const Position& p, Move ttm, Depth d, + const History& h, SearchStack* ss) : pos(p), H(h) { ttMove = ttm; - mateKiller = (mk == ttm)? MOVE_NONE : mk; - killer1 = k1; - killer2 = k2; - depth = d; - movesPicked = 0; - numOfMoves = 0; - numOfBadCaptures = 0; - dc = p.discovered_check_candidates(p.side_to_move()); + if (ss) + { + mateKiller = (ss->mateKiller == ttm)? MOVE_NONE : ss->mateKiller; + killer1 = ss->killers[0]; + killer2 = ss->killers[1]; + } else + mateKiller = killer1 = killer2 = MOVE_NONE; + + movesPicked = numOfMoves = numOfBadCaptures = 0; + checkKillers = checkLegal = finished = false; if (p.is_check()) - phaseIndex = EvasionsPhaseIndex; - else if (depth > Depth(0)) - phaseIndex = MainSearchPhaseIndex; - else if (depth == Depth(0)) - phaseIndex = QsearchWithChecksPhaseIndex; + phaseIndex = EvasionsPhaseIndex; + else if (d > Depth(0)) + phaseIndex = MainSearchPhaseIndex; + else if (d == Depth(0)) + phaseIndex = QsearchWithChecksPhaseIndex; else - phaseIndex = QsearchWithoutChecksPhaseIndex; + phaseIndex = QsearchWithoutChecksPhaseIndex; - pinned = p.pinned_pieces(p.side_to_move()); + Color us = pos.side_to_move(); + + dc = p.discovered_check_candidates(us); + pinned = p.pinned_pieces(us); finished = false; } @@ -127,40 +133,60 @@ Move MovePicker::get_next_move() { assert(move_is_ok(mateKiller)); if (move_is_legal(pos, mateKiller, pinned)) return mateKiller; - } - break; + } + break; case PH_GOOD_CAPTURES: numOfMoves = generate_captures(pos, moves); score_captures(); + std::sort(moves, moves + numOfMoves); movesPicked = 0; + checkLegal = true; break; - case PH_BAD_CAPTURES: - badCapturesPicked = 0; + case PH_KILLERS: + movesPicked = numOfMoves = 0; + checkLegal = false; + if (killer1 != MOVE_NONE && move_is_legal(pos, killer1, pinned) && !pos.move_is_capture(killer1)) + moves[numOfMoves++].move = killer1; + if (killer2 != MOVE_NONE && move_is_legal(pos, killer2, pinned) && !pos.move_is_capture(killer2) ) + moves[numOfMoves++].move = killer2; break; case PH_NONCAPTURES: + checkKillers = (numOfMoves != 0); // previous phase is PH_KILLERS numOfMoves = generate_noncaptures(pos, moves); score_noncaptures(); + std::sort(moves, moves + numOfMoves); + movesPicked = 0; + checkLegal = true; + break; + + case PH_BAD_CAPTURES: + // Bad captures SEE value is already calculated by score_captures() + // so just sort them to get SEE move ordering. + std::sort(badCaptures, badCaptures + numOfBadCaptures); movesPicked = 0; break; case PH_EVASIONS: assert(pos.is_check()); - numOfMoves = generate_evasions(pos, moves); + numOfMoves = generate_evasions(pos, moves, pinned); score_evasions(); + std::sort(moves, moves + numOfMoves); movesPicked = 0; break; case PH_QCAPTURES: numOfMoves = generate_captures(pos, moves); score_qcaptures(); + std::sort(moves, moves + numOfMoves); movesPicked = 0; break; case PH_QCHECKS: - numOfMoves = generate_checks(pos, moves, dc); + // Perhaps we should order moves move here? FIXME + numOfMoves = generate_non_capture_checks(pos, moves, dc); movesPicked = 0; break; @@ -210,6 +236,8 @@ void MovePicker::score_captures() { // where it is possible to recapture with the hanging piece). Exchanging // big pieces before capturing a hanging piece probably helps to reduce // the subtree size. + // While scoring captures it moves all captures with negative SEE values + // to the badCaptures[] array. Move m; int seeValue; @@ -219,13 +247,20 @@ void MovePicker::score_captures() { seeValue = pos.see(m); if (seeValue >= 0) { - if (move_promotion(m)) + if (move_is_promotion(m)) moves[i].score = QueenValueMidgame; else moves[i].score = int(pos.midgame_value_of_piece_on(move_to(m))) -int(pos.type_of_piece_on(move_from(m))); - } else + } + else + { + // Losing capture, move it to the badCaptures[] array + assert(numOfBadCaptures < 63); moves[i].score = seeValue; + badCaptures[numOfBadCaptures++] = moves[i]; + moves[i--] = moves[--numOfMoves]; + } } } @@ -233,25 +268,23 @@ void MovePicker::score_noncaptures() { // First score by history, when no history is available then use // piece/square tables values. This seems to be better then a // random choice when we don't have an history for any move. - Move m; - int hs; - - for (int i = 0; i < numOfMoves; i++) - { - m = moves[i].move; - - if (m == killer1) - hs = HistoryMax + 2; - else if (m == killer2) - hs = HistoryMax + 1; - else - hs = H.move_ordering_score(pos.piece_on(move_from(m)), m); - - // Ensure moves in history are always sorted as first - if (hs > 0) - hs += 1000; - - moves[i].score = hs + pos.mg_pst_delta(m); + Piece piece; + Square from, to; + int hs; + + for (int i = 0; i < numOfMoves; i++) + { + from = move_from(moves[i].move); + to = move_to(moves[i].move); + piece = pos.piece_on(from); + hs = H.move_ordering_score(piece, to); + + // Ensure history is always preferred to pst + if (hs > 0) + hs += 1000; + + // pst based scoring + moves[i].score = hs + pos.pst_delta(piece, from, to); } } @@ -267,9 +300,8 @@ void MovePicker::score_evasions() { int seeScore = pos.see(m); moves[i].score = (seeScore >= 0)? seeScore + HistoryMax : seeScore; } else - moves[i].score = H.move_ordering_score(pos.piece_on(move_from(m)), m); + moves[i].score = H.move_ordering_score(pos.piece_on(move_from(m)), move_to(m)); } - // FIXME try psqt also here } void MovePicker::score_qcaptures() { @@ -278,7 +310,7 @@ void MovePicker::score_qcaptures() { for (int i = 0; i < numOfMoves; i++) { Move m = moves[i].move; - if (move_promotion(m)) + if (move_is_promotion(m)) moves[i].score = QueenValueMidgame; else moves[i].score = int(pos.midgame_value_of_piece_on(move_to(m))) @@ -287,121 +319,43 @@ void MovePicker::score_qcaptures() { } -/// find_best_index() loops across the moves and returns index of -/// the highest scored one. - -int MovePicker::find_best_index() { - - int bestScore = -10000000, bestIndex = -1; - - for (int i = movesPicked; i < numOfMoves; i++) - if (moves[i].score > bestScore) - { - bestIndex = i; - bestScore = moves[i].score; - } - return bestIndex; -} - - /// MovePicker::pick_move_from_list() picks the move with the biggest score /// from a list of generated moves (moves[] or badCaptures[], depending on /// the current move generation phase). It takes care not to return the /// transposition table move if that has already been serched previously. -/// While picking captures in the PH_GOOD_CAPTURES phase (i.e. while picking -/// non-losing captures in the main search), it moves all captures with -/// negative SEE values to the badCaptures[] array. Move MovePicker::pick_move_from_list() { - int bestIndex; - Move move; + assert(movesPicked >= 0); + assert(!pos.is_check() || PhaseTable[phaseIndex] == PH_EVASIONS || PhaseTable[phaseIndex] == PH_STOP); + assert( pos.is_check() || PhaseTable[phaseIndex] != PH_EVASIONS); switch (PhaseTable[phaseIndex]) { - case PH_GOOD_CAPTURES: - assert(!pos.is_check()); - assert(movesPicked >= 0); - - while (movesPicked < numOfMoves) - { - int bestScore = -10000000; - bestIndex = -1; - for (int i = movesPicked; i < numOfMoves; i++) - { - if (moves[i].score < 0) - { - // Losing capture, move it to the badCaptures[] array - assert(numOfBadCaptures < 63); - badCaptures[numOfBadCaptures++] = moves[i]; - moves[i--] = moves[--numOfMoves]; - } - else if (moves[i].score > bestScore) - { - bestIndex = i; - bestScore = moves[i].score; - } - } - if (bestIndex != -1) // Found a good capture - { - move = moves[bestIndex].move; - moves[bestIndex] = moves[movesPicked++]; - if ( move != ttMove - && move != mateKiller - && pos.pl_move_is_legal(move, pinned)) - return move; - } - } - break; + case PH_GOOD_CAPTURES: + case PH_KILLERS: case PH_NONCAPTURES: - assert(!pos.is_check()); - assert(movesPicked >= 0); - while (movesPicked < numOfMoves) { - // If this is a PV node or we have only picked a few moves, scan - // the entire move list for the best move. If many moves have already - // been searched and it is not a PV node, we are probably failing low - // anyway, so we just pick the first move from the list. - bestIndex = (pvNode || movesPicked < 12) ? find_best_index() : movesPicked; - - if (bestIndex != -1) - { - move = moves[bestIndex].move; - moves[bestIndex] = moves[movesPicked++]; - if ( move != ttMove - && move != mateKiller - && pos.pl_move_is_legal(move, pinned)) - return move; - } + Move move = moves[movesPicked++].move; + if ( move != ttMove + && move != mateKiller + && (!checkKillers || (move != killer1 && move != killer2)) + && (!checkLegal || pos.pl_move_is_legal(move, pinned))) + return move; } break; case PH_EVASIONS: - assert(pos.is_check()); - assert(movesPicked >= 0); + if (movesPicked < numOfMoves) + return moves[movesPicked++].move; - while (movesPicked < numOfMoves) - { - bestIndex = find_best_index(); - - if (bestIndex != -1) - { - move = moves[bestIndex].move; - moves[bestIndex] = moves[movesPicked++]; - return move; - } - } - break; + break; case PH_BAD_CAPTURES: - assert(!pos.is_check()); - assert(badCapturesPicked >= 0); - // It's probably a good idea to use SEE move ordering here, instead - // of just picking the first move. FIXME - while (badCapturesPicked < numOfBadCaptures) + while (movesPicked < numOfBadCaptures) { - move = badCaptures[badCapturesPicked++].move; + Move move = badCaptures[movesPicked++].move; if ( move != ttMove && move != mateKiller && pos.pl_move_is_legal(move, pinned)) @@ -410,34 +364,13 @@ Move MovePicker::pick_move_from_list() { break; case PH_QCAPTURES: - assert(!pos.is_check()); - assert(movesPicked >= 0); - while (movesPicked < numOfMoves) - { - bestIndex = (movesPicked < 4 ? find_best_index() : movesPicked); - - if (bestIndex != -1) - { - move = moves[bestIndex].move; - moves[bestIndex] = moves[movesPicked++]; - // Remember to change the line below if we decide to hash the qsearch! - // Maybe also postpone the legality check until after futility pruning? - if (/* move != ttMove && */ pos.pl_move_is_legal(move, pinned)) - return move; - } - } - break; - case PH_QCHECKS: - assert(!pos.is_check()); - assert(movesPicked >= 0); - // Perhaps we should do something better than just picking the first - // move here? FIXME while (movesPicked < numOfMoves) { - move = moves[movesPicked++].move; - // Remember to change the line below if we decide to hash the qsearch! - if (/* move != ttMove && */ pos.pl_move_is_legal(move, pinned)) + Move move = moves[movesPicked++].move; + // Maybe postpone the legality check until after futility pruning? + if ( move != ttMove + && pos.pl_move_is_legal(move, pinned)) return move; } break; @@ -449,19 +382,10 @@ Move MovePicker::pick_move_from_list() { } -/// MovePicker::current_move_type() returns the type of the just -/// picked next move. It can be used in search to further differentiate -/// according to the current move type: capture, non capture, escape, etc. -MovePicker::MovegenPhase MovePicker::current_move_type() const { - - return PhaseTable[phaseIndex]; -} - - /// MovePicker::init_phase_table() initializes the PhaseTable[], /// MainSearchPhaseIndex, EvasionPhaseIndex, QsearchWithChecksPhaseIndex -/// and QsearchWithoutChecksPhaseIndex variables. It is only called once -/// during program startup, and never again while the program is running. +/// and QsearchWithoutChecksPhaseIndex. It is only called once during +/// program startup, and never again while the program is running. void MovePicker::init_phase_table() { @@ -472,9 +396,7 @@ void MovePicker::init_phase_table() { PhaseTable[i++] = PH_TT_MOVE; PhaseTable[i++] = PH_MATE_KILLER; PhaseTable[i++] = PH_GOOD_CAPTURES; - // PH_KILLER_1 and PH_KILLER_2 are not yet used. - // PhaseTable[i++] = PH_KILLER_1; - // PhaseTable[i++] = PH_KILLER_2; + PhaseTable[i++] = PH_KILLERS; PhaseTable[i++] = PH_NONCAPTURES; PhaseTable[i++] = PH_BAD_CAPTURES; PhaseTable[i++] = PH_STOP; @@ -486,12 +408,14 @@ void MovePicker::init_phase_table() { // Quiescence search with checks QsearchWithChecksPhaseIndex = i - 1; + PhaseTable[i++] = PH_TT_MOVE; PhaseTable[i++] = PH_QCAPTURES; PhaseTable[i++] = PH_QCHECKS; PhaseTable[i++] = PH_STOP; // Quiescence search without checks QsearchWithoutChecksPhaseIndex = i - 1; + PhaseTable[i++] = PH_TT_MOVE; PhaseTable[i++] = PH_QCAPTURES; PhaseTable[i++] = PH_STOP; }