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) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+ Copyright (C) 2015-2017 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
void MovePicker::score<QUIETS>() {
const HistoryStats& history = pos.this_thread()->history;
- const FromToStats& fromTo = pos.this_thread()->fromTo;
- const CounterMoveStats* cmh = (ss-1)->counterMoves;
- const CounterMoveStats* fmh = (ss-2)->counterMoves;
- const CounterMoveStats* fmh2 = (ss-4)->counterMoves;
+ const CounterMoveStats& cmh = *(ss-1)->counterMoves;
+ const CounterMoveStats& fmh = *(ss-2)->counterMoves;
+ const CounterMoveStats& fm2 = *(ss-4)->counterMoves;
Color c = pos.side_to_move();
for (auto& m : *this)
- m.value = history[pos.moved_piece(m)][to_sq(m)]
- + (cmh ? (*cmh)[pos.moved_piece(m)][to_sq(m)] : VALUE_ZERO)
- + (fmh ? (*fmh)[pos.moved_piece(m)][to_sq(m)] : VALUE_ZERO)
- + (fmh2 ? (*fmh2)[pos.moved_piece(m)][to_sq(m)] : VALUE_ZERO)
- + fromTo.get(c, m);
+ m.value = cmh[pos.moved_piece(m)][to_sq(m)]
+ + fmh[pos.moved_piece(m)][to_sq(m)]
+ + fm2[pos.moved_piece(m)][to_sq(m)]
+ + history.get(c, m);
}
template<>
void MovePicker::score<EVASIONS>() {
- // Try captures ordered by MVV/LVA, then non-captures ordered by history value
+ // Try captures ordered by MVV/LVA, then non-captures ordered by stats heuristics
const HistoryStats& history = pos.this_thread()->history;
- const FromToStats& fromTo = pos.this_thread()->fromTo;
Color c = pos.side_to_move();
for (auto& m : *this)
m.value = PieceValue[MG][pos.piece_on(to_sq(m))]
- Value(type_of(pos.moved_piece(m))) + HistoryStats::Max;
else
- m.value = history[pos.moved_piece(m)][to_sq(m)] + fromTo.get(c, m);
+ m.value = history.get(c, m);
}
/// left. It picks the move with the biggest value from a list of generated moves
/// taking care not to return the ttMove if it has already been searched.
-Move MovePicker::next_move() {
+Move MovePicker::next_move(bool skipQuiets) {
Move move;
++stage;
case QUIET:
- while (cur < endMoves)
+ while ( cur < endMoves
+ && (!skipQuiets || cur->value >= VALUE_ZERO))
{
move = *cur++;
+
if ( move != ttMove
&& move != ss->killers[0]
&& move != ss->killers[1]