/*
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
//// Includes
////
+#include <algorithm>
#include <cassert>
#include "history.h"
int MainSearchPhaseIndex;
int EvasionsPhaseIndex;
int QsearchWithChecksPhaseIndex;
- int QsearchNoCapturesPhaseIndex;
int QsearchWithoutChecksPhaseIndex;
- int NoMovesPhaseIndex;
}
-
////
//// Functions
////
/// move ordering is at the current node.
MovePicker::MovePicker(const Position& p, bool pv, Move ttm,
- Move mk, Move k1, Move k2, Depth d, EvalInfo* ei) : pos(p) {
+ const SearchStack& ss, Depth d) : pos(p) {
pvNode = pv;
ttMove = ttm;
- mateKiller = (mk == ttm)? MOVE_NONE : mk;
- killer1 = k1;
- killer2 = k2;
+ mateKiller = (ss.mateKiller == ttm)? MOVE_NONE : ss.mateKiller;
+ killer1 = ss.killers[0];
+ killer2 = ss.killers[1];
depth = d;
movesPicked = 0;
numOfMoves = 0;
numOfBadCaptures = 0;
-
- // With EvalInfo we are able to know how many captures are possible before
- // generating them. So avoid generating them in case we know are zero.
- Color us = pos.side_to_move();
- Color them = opposite_color(us);
- bool noAttacks = ei && (ei->attackedBy[us][0] & pos.pieces_of_color(them)) == 0;
- bool noCaptures = noAttacks && (pos.ep_square() == SQ_NONE) && !pos.has_pawn_on_7th(us);
+ checkKillers = checkLegal = false;
if (p.is_check())
phaseIndex = EvasionsPhaseIndex;
else if (depth > Depth(0))
phaseIndex = MainSearchPhaseIndex;
else if (depth == Depth(0))
- phaseIndex = (noCaptures ? QsearchNoCapturesPhaseIndex : QsearchWithChecksPhaseIndex);
+ phaseIndex = QsearchWithChecksPhaseIndex;
else
- phaseIndex = (noCaptures ? NoMovesPhaseIndex : QsearchWithoutChecksPhaseIndex);
+ phaseIndex = QsearchWithoutChecksPhaseIndex;
+ Color us = pos.side_to_move();
dc = p.discovered_check_candidates(us);
- pinned = p.pinned_pieces(p.side_to_move());
+ pinned = p.pinned_pieces(us);
finished = false;
}
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;
for (int i = 0; i < numOfMoves; i++)
{
m = moves[i].move;
+ hs = H.move_ordering_score(pos.piece_on(move_from(m)), move_to(m));
- 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
+ // Ensure history is always preferred to pst
if (hs > 0)
hs += 1000;
+ // pst based scoring
moves[i].score = hs + pos.mg_pst_delta(m);
}
}
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() {
}
-/// find_best_index() loops across the moves and returns index of\r
-/// the highest scored one. There is also a second version that\r
-/// lowers the priority of moves that attack the same square,\r
-/// so that if the best move that attack a square fails the next\r
-/// move picked attacks a different square if any, not the same 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;
-}
-
-int MovePicker::find_best_index(Bitboard* squares, int values[]) {\r
-\r
- int hs;\r
- Move m;\r
- Square to;\r
- int bestScore = -10000000, bestIndex = -1;\r
-\r
- for (int i = movesPicked; i < numOfMoves; i++)\r
- {\r
- m = moves[i].move;\r
- to = move_to(m);\r
- \r
- if (!bit_is_set(*squares, to))\r
- {\r
- // Init at first use\r
- set_bit(squares, to);\r
- values[to] = 0;\r
- }\r
-\r
- hs = moves[i].score - values[to];\r
- if (hs > bestScore)\r
- {\r
- bestIndex = i;\r
- bestScore = hs;\r
- }\r
- }\r
-\r
- if (bestIndex != -1)\r
- {\r
- // Raise value of the picked square, so next attack\r
- // to the same square will get low priority.\r
- to = move_to(moves[bestIndex].move);\r
- values[to] += 0xB00;\r
- }\r
- return bestIndex;\r
-}
-
-
/// 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
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)
- {
- bestIndex = find_best_index();
-
- 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);
-
- while (movesPicked < numOfMoves)
- {
- bestIndex = find_best_index();
+ if (movesPicked < numOfMoves)
+ return moves[movesPicked++].move;
- 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))
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;
}
-/// 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
-/// QsearchNoCapturesPhaseIndex, QsearchWithoutChecksPhaseIndex and
-/// NoMovesPhaseIndex 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() {
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;
// 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 with checks only and no captures
- QsearchNoCapturesPhaseIndex = i - 1;
- 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;
-
- // Do not generate any move
- NoMovesPhaseIndex = i - 1;
- PhaseTable[i++] = PH_STOP;
}
projects / stockfish / blobdiff