#include <iostream>
#include <set>
+#include <sstream>
+#include <iomanip>
+#include <fstream>
#include "../evaluate.h"
#include "../position.h"
}
// Evaluation function. Perform differential calculation.
- Value evaluate(const Position& pos, bool adjusted, Value lazyThreshold) {
+ Value evaluate(const Position& pos, bool adjusted) {
// We manually align the arrays on the stack because with gcc < 9.3
// overaligning stack variables with alignas() doesn't work correctly.
constexpr uint64_t alignment = CacheLineSize;
+ int delta = 7;
#if defined(ALIGNAS_ON_STACK_VARIABLES_BROKEN)
TransformedFeatureType transformedFeaturesUnaligned[
ASSERT_ALIGNED(buffer, alignment);
const std::size_t bucket = (pos.count<ALL_PIECES>() - 1) / 4;
- const auto [psqt, lazy] = featureTransformer->transform(pos, transformedFeatures, bucket, lazyThreshold);
+ const auto psqt = featureTransformer->transform(pos, transformedFeatures, bucket);
+ const auto positional = network[bucket]->propagate(transformedFeatures, buffer)[0];
- if (lazy)
- return static_cast<Value>(psqt / OutputScale);
+ // Give more value to positional evaluation when material is balanced
+ if ( adjusted
+ && abs(pos.non_pawn_material(WHITE) - pos.non_pawn_material(BLACK)) <= RookValueMg - BishopValueMg)
+ return static_cast<Value>(((128 - delta) * psqt + (128 + delta) * positional) / 128 / OutputScale);
else
- {
+ return static_cast<Value>((psqt + positional) / OutputScale);
+ }
+
+ struct NnueEvalTrace {
+ static_assert(LayerStacks == PSQTBuckets);
+
+ Value psqt[LayerStacks];
+ Value positional[LayerStacks];
+ std::size_t correctBucket;
+ };
+
+ static NnueEvalTrace trace_evaluate(const Position& pos) {
+
+ // We manually align the arrays on the stack because with gcc < 9.3
+ // overaligning stack variables with alignas() doesn't work correctly.
+
+ constexpr uint64_t alignment = CacheLineSize;
+
+#if defined(ALIGNAS_ON_STACK_VARIABLES_BROKEN)
+ TransformedFeatureType transformedFeaturesUnaligned[
+ FeatureTransformer::BufferSize + alignment / sizeof(TransformedFeatureType)];
+ char bufferUnaligned[Network::BufferSize + alignment];
+
+ auto* transformedFeatures = align_ptr_up<alignment>(&transformedFeaturesUnaligned[0]);
+ auto* buffer = align_ptr_up<alignment>(&bufferUnaligned[0]);
+#else
+ alignas(alignment)
+ TransformedFeatureType transformedFeatures[FeatureTransformer::BufferSize];
+ alignas(alignment) char buffer[Network::BufferSize];
+#endif
+
+ ASSERT_ALIGNED(transformedFeatures, alignment);
+ ASSERT_ALIGNED(buffer, alignment);
+
+ NnueEvalTrace t{};
+ t.correctBucket = (pos.count<ALL_PIECES>() - 1) / 4;
+ for (std::size_t bucket = 0; bucket < LayerStacks; ++bucket) {
+ const auto psqt = featureTransformer->transform(pos, transformedFeatures, bucket);
const auto output = network[bucket]->propagate(transformedFeatures, buffer);
int materialist = psqt;
int positional = output[0];
- int delta_npm = abs(pos.non_pawn_material(WHITE) - pos.non_pawn_material(BLACK));
- int entertainment = (adjusted && delta_npm <= BishopValueMg - KnightValueMg ? 7 : 0);
+ t.psqt[bucket] = static_cast<Value>( materialist / OutputScale );
+ t.positional[bucket] = static_cast<Value>( positional / OutputScale );
+ }
+
+ return t;
+ }
+
+ static const std::string PieceToChar(" PNBRQK pnbrqk");
- int A = 128 - entertainment;
- int B = 128 + entertainment;
- int sum = (A * materialist + B * positional) / 128;
+ // format_cp_compact() converts a Value into (centi)pawns and writes it in a buffer.
+ // The buffer must have capacity for at least 5 chars.
+ static void format_cp_compact(Value v, char* buffer) {
- return static_cast<Value>( sum / OutputScale );
+ buffer[0] = (v < 0 ? '-' : v > 0 ? '+' : ' ');
+
+ int cp = std::abs(100 * v / PawnValueEg);
+ if (cp >= 10000)
+ {
+ buffer[1] = '0' + cp / 10000; cp %= 10000;
+ buffer[2] = '0' + cp / 1000; cp %= 1000;
+ buffer[3] = '0' + cp / 100;
+ buffer[4] = ' ';
+ }
+ else if (cp >= 1000)
+ {
+ buffer[1] = '0' + cp / 1000; cp %= 1000;
+ buffer[2] = '0' + cp / 100; cp %= 100;
+ buffer[3] = '.';
+ buffer[4] = '0' + cp / 10;
}
+ else
+ {
+ buffer[1] = '0' + cp / 100; cp %= 100;
+ buffer[2] = '.';
+ buffer[3] = '0' + cp / 10; cp %= 10;
+ buffer[4] = '0' + cp / 1;
+ }
+ }
+
+
+ // format_cp_aligned_dot() converts a Value into (centi)pawns and writes it in a buffer,
+ // always keeping two decimals. The buffer must have capacity for at least 7 chars.
+ static void format_cp_aligned_dot(Value v, char* buffer) {
+
+ buffer[0] = (v < 0 ? '-' : v > 0 ? '+' : ' ');
+
+ double cp = 1.0 * std::abs(int(v)) / PawnValueEg;
+ sprintf(&buffer[1], "%6.2f", cp);
}
+
+ // trace() returns a string with the value of each piece on a board,
+ // and a table for (PSQT, Layers) values bucket by bucket.
+
+ std::string trace(Position& pos) {
+
+ std::stringstream ss;
+
+ char board[3*8+1][8*8+2];
+ std::memset(board, ' ', sizeof(board));
+ for (int row = 0; row < 3*8+1; ++row)
+ board[row][8*8+1] = '\0';
+
+ // A lambda to output one box of the board
+ auto writeSquare = [&board](File file, Rank rank, Piece pc, Value value) {
+
+ const int x = ((int)file) * 8;
+ const int y = (7 - (int)rank) * 3;
+ for (int i = 1; i < 8; ++i)
+ board[y][x+i] = board[y+3][x+i] = '-';
+ for (int i = 1; i < 3; ++i)
+ board[y+i][x] = board[y+i][x+8] = '|';
+ board[y][x] = board[y][x+8] = board[y+3][x+8] = board[y+3][x] = '+';
+ if (pc != NO_PIECE)
+ board[y+1][x+4] = PieceToChar[pc];
+ if (value != VALUE_NONE)
+ format_cp_compact(value, &board[y+2][x+2]);
+ };
+
+ // We estimate the value of each piece by doing a differential evaluation from
+ // the current base eval, simulating the removal of the piece from its square.
+ Value base = evaluate(pos);
+ base = pos.side_to_move() == WHITE ? base : -base;
+
+ for (File f = FILE_A; f <= FILE_H; ++f)
+ for (Rank r = RANK_1; r <= RANK_8; ++r)
+ {
+ Square sq = make_square(f, r);
+ Piece pc = pos.piece_on(sq);
+ Value v = VALUE_NONE;
+
+ if (pc != NO_PIECE && type_of(pc) != KING)
+ {
+ auto st = pos.state();
+
+ pos.remove_piece(sq);
+ st->accumulator.computed[WHITE] = false;
+ st->accumulator.computed[BLACK] = false;
+
+ Value eval = evaluate(pos);
+ eval = pos.side_to_move() == WHITE ? eval : -eval;
+ v = base - eval;
+
+ pos.put_piece(pc, sq);
+ st->accumulator.computed[WHITE] = false;
+ st->accumulator.computed[BLACK] = false;
+ }
+
+ writeSquare(f, r, pc, v);
+ }
+
+ ss << " NNUE derived piece values:\n";
+ for (int row = 0; row < 3*8+1; ++row)
+ ss << board[row] << '\n';
+ ss << '\n';
+
+ auto t = trace_evaluate(pos);
+
+ ss << " NNUE network contributions "
+ << (pos.side_to_move() == WHITE ? "(White to move)" : "(Black to move)") << std::endl
+ << "+------------+------------+------------+------------+\n"
+ << "| Bucket | Material | Positional | Total |\n"
+ << "| | (PSQT) | (Layers) | |\n"
+ << "+------------+------------+------------+------------+\n";
+
+ for (std::size_t bucket = 0; bucket < LayerStacks; ++bucket)
+ {
+ char buffer[3][8];
+ std::memset(buffer, '\0', sizeof(buffer));
+
+ format_cp_aligned_dot(t.psqt[bucket], buffer[0]);
+ format_cp_aligned_dot(t.positional[bucket], buffer[1]);
+ format_cp_aligned_dot(t.psqt[bucket] + t.positional[bucket], buffer[2]);
+
+ ss << "| " << bucket << " "
+ << " | " << buffer[0] << " "
+ << " | " << buffer[1] << " "
+ << " | " << buffer[2] << " "
+ << " |";
+ if (bucket == t.correctBucket)
+ ss << " <-- this bucket is used";
+ ss << '\n';
+ }
+
+ ss << "+------------+------------+------------+------------+\n";
+
+ return ss.str();
+ }
+
+
// Load eval, from a file stream or a memory stream
bool load_eval(std::string name, std::istream& stream) {
return write_parameters(stream);
}
+ /// Save eval, to a file given by its name
+ bool save_eval(const std::optional<std::string>& filename) {
+
+ std::string actualFilename;
+ std::string msg;
+
+ if (filename.has_value())
+ actualFilename = filename.value();
+ else
+ {
+ if (currentEvalFileName != EvalFileDefaultName)
+ {
+ msg = "Failed to export a net. A non-embedded net can only be saved if the filename is specified";
+
+ sync_cout << msg << sync_endl;
+ return false;
+ }
+ actualFilename = EvalFileDefaultName;
+ }
+
+ std::ofstream stream(actualFilename, std::ios_base::binary);
+ bool saved = save_eval(stream);
+
+ msg = saved ? "Network saved successfully to " + actualFilename
+ : "Failed to export a net";
+
+ sync_cout << msg << sync_endl;
+ return saved;
+ }
+
+
} // namespace Stockfish::Eval::NNUE