Revert "Compressed network parameters"

Joachim26 · Joachim26 · commit 9d6b82b1e333 · 2023-06-20T03:45:06.000+02:00
This reverts commit a46087e.
diff --git a/src/evaluate.h b/src/evaluate.h
@@ -39,7 +39,7 @@ namespace Eval {
   // The default net name MUST follow the format nn-[SHA256 first 12 digits].nnue
   // for the build process (profile-build and fishtest) to work. Do not change the
   // name of the macro, as it is used in the Makefile.
-  #define EvalFileDefaultName   "nn-78bacfcee510.nnue"
+  #define EvalFileDefaultName   "nn-cd2ff4716c34.nnue"
 
   namespace NNUE {
 
diff --git a/src/nnue/nnue_common.h b/src/nnue/nnue_common.h
@@ -57,9 +57,6 @@ namespace Stockfish::Eval::NNUE {
   // Size of cache line (in bytes)
   constexpr std::size_t CacheLineSize = 64;
 
-  constexpr const char Leb128MagicString[] = "COMPRESSED_LEB128";
-  constexpr const std::size_t Leb128MagicStringSize = sizeof(Leb128MagicString) - 1;
-
   // SIMD width (in bytes)
   #if defined(USE_AVX2)
   constexpr std::size_t SimdWidth = 32;
@@ -162,80 +159,6 @@ namespace Stockfish::Eval::NNUE {
               write_little_endian<IntType>(stream, values[i]);
   }
 
-  template <typename IntType>
-  inline void read_leb_128(std::istream& stream, IntType* out, std::size_t count) {
-      static_assert(std::is_signed_v<IntType>, "Not implemented for unsigned types");
-      char leb128MagicString[Leb128MagicStringSize];
-      stream.read(leb128MagicString, Leb128MagicStringSize);
-      assert(strncmp(Leb128MagicString, leb128MagicString, Leb128MagicStringSize) == 0);
-      const std::uint32_t BUF_SIZE = 4096;
-      std::uint8_t buf[BUF_SIZE];
-      auto bytes_left = read_little_endian<std::uint32_t>(stream);
-      std::uint32_t buf_pos = BUF_SIZE;
-      for (std::size_t i = 0; i < count; ++i) {
-          IntType result = 0;
-          size_t shift = 0;
-          do {
-              if (buf_pos == BUF_SIZE) {
-                  stream.read(reinterpret_cast<char*>(buf), std::min(bytes_left, BUF_SIZE));
-                  buf_pos = 0;
-              }
-              std::uint8_t byte = buf[buf_pos++];
-              --bytes_left;
-              result |= (byte & 0x7f) << shift;
-              shift += 7;
-              if ((byte & 0x80) == 0) {
-                  out[i] = sizeof(IntType) * 8 <= shift || (byte & 0x40) == 0 ? result : result | ~((1 << shift) - 1);
-                  break;
-              }
-          } while (shift < sizeof(IntType) * 8);
-      }
-      assert(bytes_left == 0);
-  }
-
-  template <typename IntType>
-  inline void write_leb_128(std::ostream& stream, const IntType* values, std::size_t count) {
-      static_assert(std::is_signed_v<IntType>, "Not implemented for unsigned types");
-      stream.write(Leb128MagicString, Leb128MagicStringSize);
-      std::uint32_t byte_count = 0;
-      for (std::size_t i = 0; i < count; ++i) {
-          IntType value = values[i];
-          std::uint8_t byte;
-          do {
-              byte = value & 0x7f;
-              value >>= 7;
-              ++byte_count;
-          } while ((byte & 0x40) == 0 ? value != 0 : value != -1);
-      }
-      write_little_endian(stream, byte_count);
-      const std::uint32_t BUF_SIZE = 4096;
-      std::uint8_t buf[BUF_SIZE];
-      std::uint32_t buf_pos = 0;
-      auto flush = [&]() {
-          if (buf_pos > 0) {
-              stream.write(reinterpret_cast<char*>(buf), buf_pos);
-              buf_pos = 0;
-          }
-      };
-      auto write = [&](std::uint8_t byte) {
-          buf[buf_pos++] = byte;
-          if (buf_pos == BUF_SIZE) flush();
-      };
-      for (std::size_t i = 0; i < count; ++i) {
-          IntType value = values[i];
-          while (true) {
-              std::uint8_t byte = value & 0x7f;
-              value >>= 7;
-              if ((byte & 0x40) == 0 ? value == 0 : value == -1) {
-                  write(byte);
-                  break;
-              }
-              write(byte | 0x80);
-          }
-      }
-      flush();
-  }
-
 }  // namespace Stockfish::Eval::NNUE
 
 #endif // #ifndef NNUE_COMMON_H_INCLUDED
diff --git a/src/nnue/nnue_feature_transformer.h b/src/nnue/nnue_feature_transformer.h
@@ -253,19 +253,19 @@ namespace Stockfish::Eval::NNUE {
     // Read network parameters
     bool read_parameters(std::istream& stream) {
 
-      read_leb_128<BiasType      >(stream, biases     , HalfDimensions                  );
-      read_leb_128<WeightType    >(stream, weights    , HalfDimensions * InputDimensions);
-      read_leb_128<PSQTWeightType>(stream, psqtWeights, PSQTBuckets    * InputDimensions);
+      read_little_endian<BiasType      >(stream, biases     , HalfDimensions                  );
+      read_little_endian<WeightType    >(stream, weights    , HalfDimensions * InputDimensions);
+      read_little_endian<PSQTWeightType>(stream, psqtWeights, PSQTBuckets    * InputDimensions);
 
       return !stream.fail();
     }
 
     // Write network parameters
     bool write_parameters(std::ostream& stream) const {
 
-      write_leb_128<BiasType      >(stream, biases     , HalfDimensions                  );
-      write_leb_128<WeightType    >(stream, weights    , HalfDimensions * InputDimensions);
-      write_leb_128<PSQTWeightType>(stream, psqtWeights, PSQTBuckets    * InputDimensions);
+      write_little_endian<BiasType      >(stream, biases     , HalfDimensions                  );
+      write_little_endian<WeightType    >(stream, weights    , HalfDimensions * InputDimensions);
+      write_little_endian<PSQTWeightType>(stream, psqtWeights, PSQTBuckets    * InputDimensions);
 
       return !stream.fail();
     }
