/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
- Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
+ Copyright (C) 2004-2023 The Stockfish developers (see AUTHORS file)
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
stage = (pos.checkers() ? EVASION_TT : QSEARCH_TT) +
!( ttm
- && (pos.checkers() || depth > DEPTH_QS_RECAPTURES || to_sq(ttm) == recaptureSquare)
&& pos.pseudo_legal(ttm));
}
/// MovePicker constructor for ProbCut: we generate captures with SEE greater
/// than or equal to the given threshold.
-MovePicker::MovePicker(const Position& p, Move ttm, Value th, Depth d, const CapturePieceToHistory* cph)
- : pos(p), captureHistory(cph), ttMove(ttm), threshold(th), depth(d)
+MovePicker::MovePicker(const Position& p, Move ttm, Value th, const CapturePieceToHistory* cph)
+ : pos(p), captureHistory(cph), ttMove(ttm), threshold(th)
{
assert(!pos.checkers());
- stage = PROBCUT_TT + !(ttm && pos.capture(ttm)
+ stage = PROBCUT_TT + !(ttm && pos.capture_stage(ttm)
&& pos.pseudo_legal(ttm)
&& pos.see_ge(ttm, threshold));
}
/// MovePicker::score() assigns a numerical value to each move in a list, used
/// for sorting. Captures are ordered by Most Valuable Victim (MVV), preferring
-/// captures with a good history. Quiets moves are ordered using the histories.
+/// captures with a good history. Quiets moves are ordered using the history tables.
template<GenType Type>
void MovePicker::score() {
static_assert(Type == CAPTURES || Type == QUIETS || Type == EVASIONS, "Wrong type");
- [[maybe_unused]] Bitboard threatened, threatenedByPawn, threatenedByMinor, threatenedByRook;
+ [[maybe_unused]] Bitboard threatenedByPawn, threatenedByMinor, threatenedByRook, threatenedPieces;
if constexpr (Type == QUIETS)
{
Color us = pos.side_to_move();
- // squares threatened by pawns
+
threatenedByPawn = pos.attacks_by<PAWN>(~us);
- // squares threatened by minors or pawns
threatenedByMinor = pos.attacks_by<KNIGHT>(~us) | pos.attacks_by<BISHOP>(~us) | threatenedByPawn;
- // squares threatened by rooks, minors or pawns
threatenedByRook = pos.attacks_by<ROOK>(~us) | threatenedByMinor;
- // pieces threatened by pieces of lesser material value
- threatened = (pos.pieces(us, QUEEN) & threatenedByRook)
- | (pos.pieces(us, ROOK) & threatenedByMinor)
- | (pos.pieces(us, KNIGHT, BISHOP) & threatenedByPawn);
+ // Pieces threatened by pieces of lesser material value
+ threatenedPieces = (pos.pieces(us, QUEEN) & threatenedByRook)
+ | (pos.pieces(us, ROOK) & threatenedByMinor)
+ | (pos.pieces(us, KNIGHT, BISHOP) & threatenedByPawn);
}
for (auto& m : *this)
if constexpr (Type == CAPTURES)
- m.value = 6 * int(PieceValue[MG][pos.piece_on(to_sq(m))])
- + (*captureHistory)[pos.moved_piece(m)][to_sq(m)][type_of(pos.piece_on(to_sq(m)))];
+ m.value = (7 * int(PieceValue[MG][pos.piece_on(to_sq(m))])
+ + (*captureHistory)[pos.moved_piece(m)][to_sq(m)][type_of(pos.piece_on(to_sq(m)))]) / 16;
else if constexpr (Type == QUIETS)
- m.value = 2 * (*mainHistory)[pos.side_to_move()][from_to(m)]
- + 2 * (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
- + (*continuationHistory[1])[pos.moved_piece(m)][to_sq(m)]
- + (*continuationHistory[3])[pos.moved_piece(m)][to_sq(m)]
- + (*continuationHistory[5])[pos.moved_piece(m)][to_sq(m)]
- + (threatened & from_sq(m) ?
- (type_of(pos.moved_piece(m)) == QUEEN && !(to_sq(m) & threatenedByRook) ? 50000
- : type_of(pos.moved_piece(m)) == ROOK && !(to_sq(m) & threatenedByMinor) ? 25000
- : !(to_sq(m) & threatenedByPawn) ? 15000
- : 0)
- : 0)
- + bool(pos.check_squares(type_of(pos.moved_piece(m))) & to_sq(m)) * 16384;
+ {
+ Piece pc = pos.moved_piece(m);
+ PieceType pt = type_of(pos.moved_piece(m));
+ Square from = from_sq(m);
+ Square to = to_sq(m);
+
+ // histories
+ m.value = 2 * (*mainHistory)[pos.side_to_move()][from_to(m)];
+ m.value += 2 * (*continuationHistory[0])[pc][to];
+ m.value += (*continuationHistory[1])[pc][to];
+ m.value += (*continuationHistory[3])[pc][to];
+ m.value += (*continuationHistory[5])[pc][to];
+
+ // bonus for checks
+ m.value += bool(pos.check_squares(pt) & to) * 16384;
+
+ // bonus for escaping from capture
+ m.value += threatenedPieces & from ?
+ (pt == QUEEN && !(to & threatenedByRook) ? 50000
+ : pt == ROOK && !(to & threatenedByMinor) ? 25000
+ : !(to & threatenedByPawn) ? 15000
+ : 0 )
+ : 0 ;
+
+ // malus for putting piece en prise
+ m.value -= !(threatenedPieces & from) ?
+ (pt == QUEEN ? bool(to & threatenedByRook) * 50000
+ + bool(to & threatenedByMinor) * 10000
+ + bool(to & threatenedByPawn) * 20000
+ : pt == ROOK ? bool(to & threatenedByMinor) * 25000
+ + bool(to & threatenedByPawn) * 10000
+ : pt != PAWN ? bool(to & threatenedByPawn) * 15000
+ : 0 )
+ : 0 ;
+ }
+
else // Type == EVASIONS
{
- if (pos.capture(m))
+ if (pos.capture_stage(m))
m.value = PieceValue[MG][pos.piece_on(to_sq(m))]
- Value(type_of(pos.moved_piece(m)))
+ (1 << 28);
while (cur < endMoves)
{
- if (T == Best)
+ if constexpr (T == Best)
std::swap(*cur, *std::max_element(cur, endMoves));
if (*cur != ttMove && filter())
endMoves = generate<CAPTURES>(pos, cur);
score<CAPTURES>();
- partial_insertion_sort(cur, endMoves, -3000 * depth);
+ partial_insertion_sort(cur, endMoves, std::numeric_limits<int>::min());
++stage;
goto top;
case GOOD_CAPTURE:
if (select<Next>([&](){
- return pos.see_ge(*cur, Value(-69 * cur->value / 1024)) ?
+ return pos.see_ge(*cur, Value(-cur->value)) ?
// Move losing capture to endBadCaptures to be tried later
true : (*endBadCaptures++ = *cur, false); }))
return *(cur - 1);
case REFUTATION:
if (select<Next>([&](){ return *cur != MOVE_NONE
- && !pos.capture(*cur)
+ && !pos.capture_stage(*cur)
&& pos.pseudo_legal(*cur); }))
return *(cur - 1);
++stage;
projects / stockfish / blobdiff