#include "misc.h"
#include "pawns.h"
#include "thread.h"
+#include "timeman.h"
#include "uci.h"
#include "incbin/incbin.h"
-// Macro to embed the default NNUE file data in the engine binary (using incbin.h, by Dale Weiler).
+// Macro to embed the default efficiently updatable neural network (NNUE) file
+// data in the engine binary (using incbin.h, by Dale Weiler).
// This macro invocation will declare the following three variables
// const unsigned char gEmbeddedNNUEData[]; // a pointer to the embedded data
// const unsigned char *const gEmbeddedNNUEEnd; // a marker to the end
// const unsigned int gEmbeddedNNUESize; // the size of the embedded file
-// Note that this does not work in Microsof Visual Studio.
+// Note that this does not work in Microsoft Visual Studio.
#if !defined(_MSC_VER) && !defined(NNUE_EMBEDDING_OFF)
INCBIN(EmbeddedNNUE, EvalFileDefaultName);
#else
using namespace std;
-using namespace Eval::NNUE;
+
+namespace Stockfish {
namespace Eval {
bool useNNUE;
string eval_file_loaded = "None";
- /// NNUE::init() tries to load a nnue network at startup time, or when the engine
+ /// NNUE::init() tries to load a NNUE network at startup time, or when the engine
/// receives a UCI command "setoption name EvalFile value nn-[a-z0-9]{12}.nnue"
- /// The name of the nnue network is always retrieved from the EvalFile option.
+ /// The name of the NNUE network is always retrieved from the EvalFile option.
/// We search the given network in three locations: internally (the default
/// network may be embedded in the binary), in the active working directory and
/// in the engine directory. Distro packagers may define the DEFAULT_NNUE_DIRECTORY
}
}
+ /// NNUE::export_net() exports the currently loaded network to a file
+ void NNUE::export_net(const std::optional<std::string>& filename) {
+ std::string actualFilename;
+
+ if (filename.has_value())
+ actualFilename = filename.value();
+ else
+ {
+ if (eval_file_loaded != EvalFileDefaultName)
+ {
+ sync_cout << "Failed to export a net. A non-embedded net can only be saved if the filename is specified." << sync_endl;
+ return;
+ }
+ actualFilename = EvalFileDefaultName;
+ }
+
+ ofstream stream(actualFilename, std::ios_base::binary);
+
+ if (save_eval(stream))
+ sync_cout << "Network saved successfully to " << actualFilename << "." << sync_endl;
+ else
+ sync_cout << "Failed to export a net." << sync_endl;
+ }
+
/// NNUE::verify() verifies that the last net used was loaded successfully
void NNUE::verify() {
S(0, 0), S(3, 44), S(37, 68), S(42, 60), S(0, 39), S(58, 43)
};
+ constexpr Value CorneredBishop = Value(50);
+
// Assorted bonuses and penalties
constexpr Score UncontestedOutpost = S( 1, 10);
constexpr Score BishopOnKingRing = S( 24, 0);
constexpr Score BishopXRayPawns = S( 4, 5);
- constexpr Score CorneredBishop = S( 50, 50);
constexpr Score FlankAttacks = S( 8, 0);
constexpr Score Hanging = S( 69, 36);
constexpr Score KnightOnQueen = S( 16, 11);
attackedBy[Us][Pt] = 0;
- while (b1) {
- Square s = pop_lsb(&b1);
+ while (b1)
+ {
+ Square s = pop_lsb(b1);
// Find attacked squares, including x-ray attacks for bishops and rooks
b = Pt == BISHOP ? attacks_bb<BISHOP>(s, pos.pieces() ^ pos.pieces(QUEEN))
score += BishopOnKingRing;
int mob = popcount(b & mobilityArea[Us]);
-
mobility[Us] += MobilityBonus[Pt - 2][mob];
if (Pt == BISHOP || Pt == KNIGHT)
// Penalty if the piece is far from the king
score -= KingProtector[Pt == BISHOP] * distance(pos.square<KING>(Us), s);
- if (Pt == BISHOP)
+ if constexpr (Pt == BISHOP)
{
// Penalty according to the number of our pawns on the same color square as the
// bishop, bigger when the center files are blocked with pawns and smaller
{
Direction d = pawn_push(Us) + (file_of(s) == FILE_A ? EAST : WEST);
if (pos.piece_on(s + d) == make_piece(Us, PAWN))
- score -= !pos.empty(s + d + pawn_push(Us)) ? CorneredBishop * 4
- : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? CorneredBishop * 2
- : CorneredBishop;
+ score -= !pos.empty(s + d + pawn_push(Us)) ? 4 * make_score(CorneredBishop, CorneredBishop)
+ : 3 * make_score(CorneredBishop, CorneredBishop);
}
}
}
- if (Pt == ROOK)
+ if constexpr (Pt == ROOK)
{
// Bonuses for rook on a (semi-)open or closed file
if (pos.is_on_semiopen_file(Us, s))
}
}
- if (Pt == QUEEN)
+ if constexpr (Pt == QUEEN)
{
// Penalty if any relative pin or discovered attack against the queen
Bitboard queenPinners;
score -= WeakQueen;
}
}
- if (T)
+ if constexpr (T)
Trace::add(Pt, Us, score);
return score;
// Penalty if king flank is under attack, potentially moving toward the king
score -= FlankAttacks * kingFlankAttack;
- if (T)
+ if constexpr (T)
Trace::add(KING, Us, score);
return score;
{
b = (defended | weak) & (attackedBy[Us][KNIGHT] | attackedBy[Us][BISHOP]);
while (b)
- score += ThreatByMinor[type_of(pos.piece_on(pop_lsb(&b)))];
+ score += ThreatByMinor[type_of(pos.piece_on(pop_lsb(b)))];
b = weak & attackedBy[Us][ROOK];
while (b)
- score += ThreatByRook[type_of(pos.piece_on(pop_lsb(&b)))];
+ score += ThreatByRook[type_of(pos.piece_on(pop_lsb(b)))];
if (weak & attackedBy[Us][KING])
score += ThreatByKing;
score += SliderOnQueen * popcount(b & safe & attackedBy2[Us]) * (1 + queenImbalance);
}
- if (T)
+ if constexpr (T)
Trace::add(THREAT, Us, score);
return score;
while (b)
{
- Square s = pop_lsb(&b);
+ Square s = pop_lsb(b);
assert(!(pos.pieces(Them, PAWN) & forward_file_bb(Us, s + Up)));
score += bonus - PassedFile * edge_distance(file_of(s));
}
- if (T)
+ if constexpr (T)
Trace::add(PASSED, Us, score);
return score;
int weight = pos.count<ALL_PIECES>(Us) - 3 + std::min(pe->blocked_count(), 9);
Score score = make_score(bonus * weight * weight / 16, 0);
- if (T)
+ if constexpr (T)
Trace::add(SPACE, Us, score);
return score;
Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK;
int sf = me->scale_factor(pos, strongSide);
- // If scale factor is not already specific, scale down via general heuristics
+ // If scale factor is not already specific, scale up/down via general heuristics
if (sf == SCALE_FACTOR_NORMAL)
{
if (pos.opposite_bishops())
+ eg * int(PHASE_MIDGAME - me->game_phase()) * ScaleFactor(sf) / SCALE_FACTOR_NORMAL;
v /= PHASE_MIDGAME;
- if (T)
+ if constexpr (T)
{
Trace::add(WINNABLE, make_score(u, eg * ScaleFactor(sf) / SCALE_FACTOR_NORMAL - eg_value(score)));
Trace::add(TOTAL, make_score(mg, eg * ScaleFactor(sf) / SCALE_FACTOR_NORMAL));
Value v = winnable(score);
// In case of tracing add all remaining individual evaluation terms
- if (T)
+ if constexpr (T)
{
Trace::add(MATERIAL, pos.psq_score());
Trace::add(IMBALANCE, me->imbalance());
return v;
}
-} // namespace
+
+ /// Fisher Random Chess: correction for cornered bishops, to fix chess960 play with NNUE
+
+ Value fix_FRC(const Position& pos) {
+
+ constexpr Bitboard Corners = 1ULL << SQ_A1 | 1ULL << SQ_H1 | 1ULL << SQ_A8 | 1ULL << SQ_H8;
+
+ if (!(pos.pieces(BISHOP) & Corners))
+ return VALUE_ZERO;
+
+ int correction = 0;
+
+ if ( pos.piece_on(SQ_A1) == W_BISHOP
+ && pos.piece_on(SQ_B2) == W_PAWN)
+ correction += !pos.empty(SQ_B3) ? -CorneredBishop * 4
+ : -CorneredBishop * 3;
+
+ if ( pos.piece_on(SQ_H1) == W_BISHOP
+ && pos.piece_on(SQ_G2) == W_PAWN)
+ correction += !pos.empty(SQ_G3) ? -CorneredBishop * 4
+ : -CorneredBishop * 3;
+
+ if ( pos.piece_on(SQ_A8) == B_BISHOP
+ && pos.piece_on(SQ_B7) == B_PAWN)
+ correction += !pos.empty(SQ_B6) ? CorneredBishop * 4
+ : CorneredBishop * 3;
+
+ if ( pos.piece_on(SQ_H8) == B_BISHOP
+ && pos.piece_on(SQ_G7) == B_PAWN)
+ correction += !pos.empty(SQ_G6) ? CorneredBishop * 4
+ : CorneredBishop * 3;
+
+ return pos.side_to_move() == WHITE ? Value(correction)
+ : -Value(correction);
+ }
+
+} // namespace Eval
/// evaluate() is the evaluator for the outer world. It returns a static
else
{
// Scale and shift NNUE for compatibility with search and classical evaluation
- auto adjusted_NNUE = [&](){
- int mat = pos.non_pawn_material() + PawnValueMg * pos.count<PAWN>();
- return NNUE::evaluate(pos) * (679 + mat / 32) / 1024 + Tempo;
+ auto adjusted_NNUE = [&]()
+ {
+ int material = pos.non_pawn_material() + 4 * PawnValueMg * pos.count<PAWN>();
+ int scale = 580
+ + material / 32
+ - 4 * pos.rule50_count();
+
+ Value nnue = NNUE::evaluate(pos) * scale / 1024 + Time.tempoNNUE;
+
+ if (pos.is_chess960())
+ nnue += fix_FRC(pos);
+
+ return nnue;
};
- // If there is PSQ imbalance use classical eval, with small probability if it is small
+ // If there is PSQ imbalance we use the classical eval. We also introduce
+ // a small probability of using the classical eval when PSQ imbalance is small.
Value psq = Value(abs(eg_value(pos.psq_score())));
int r50 = 16 + pos.rule50_count();
bool largePsq = psq * 16 > (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50;
bool classical = largePsq || (psq > PawnValueMg / 4 && !(pos.this_thread()->nodes & 0xB));
// Use classical evaluation for really low piece endgames.
- // The most critical case is a bishop + A/H file pawn vs naked king draw.
- bool strongClassical = pos.non_pawn_material() < 2 * RookValueMg && pos.count<PAWN>() < 2;
+ // One critical case is the draw for bishop + A/H file pawn vs naked king.
+ bool lowPieceEndgame = pos.non_pawn_material() == BishopValueMg
+ || (pos.non_pawn_material() < 2 * RookValueMg && pos.count<PAWN>() < 2);
- v = classical || strongClassical ? Evaluation<NO_TRACE>(pos).value() : adjusted_NNUE();
+ v = classical || lowPieceEndgame ? Evaluation<NO_TRACE>(pos).value()
+ : adjusted_NNUE();
// If the classical eval is small and imbalance large, use NNUE nevertheless.
- // For the case of opposite colored bishops, switch to NNUE eval with
- // small probability if the classical eval is less than the threshold.
- if ( largePsq && !strongClassical
+ // For the case of opposite colored bishops, switch to NNUE eval with small
+ // probability if the classical eval is less than the threshold.
+ if ( largePsq
+ && !lowPieceEndgame
&& ( abs(v) * 16 < NNUEThreshold2 * r50
|| ( pos.opposite_bishops()
&& abs(v) * 16 < (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50
return ss.str();
}
+
+} // namespace Stockfish
projects / stockfish / blobdiff