X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fnnue%2Fnnue_common.h;h=12309d262b17ddacd5239694383244fb98d10d9d;hb=HEAD;hp=390f61c35ad4c1c7e0119fc3b83eed17e39a2fc3;hpb=b84fa04db6ea5fc6d7d714539c11537bde64538b;p=stockfish

diff --git a/src/nnue/nnue_common.h b/src/nnue/nnue_common.h
index 390f61c3..f9cd7fbb 100644
--- a/src/nnue/nnue_common.h
+++ b/src/nnue/nnue_common.h
@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 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
@@ -21,144 +21,264 @@
 #ifndef NNUE_COMMON_H_INCLUDED
 #define NNUE_COMMON_H_INCLUDED
 
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
 #include <cstring>
 #include <iostream>
+#include <type_traits>
 
-#include "../misc.h"  // for IsLittleEndian
+#include "../misc.h"
 
 #if defined(USE_AVX2)
-#include <immintrin.h>
+    #include <immintrin.h>
 
 #elif defined(USE_SSE41)
-#include <smmintrin.h>
+    #include <smmintrin.h>
 
 #elif defined(USE_SSSE3)
-#include <tmmintrin.h>
+    #include <tmmintrin.h>
 
 #elif defined(USE_SSE2)
-#include <emmintrin.h>
-
-#elif defined(USE_MMX)
-#include <mmintrin.h>
+    #include <emmintrin.h>
 
 #elif defined(USE_NEON)
-#include <arm_neon.h>
+    #include <arm_neon.h>
 #endif
 
 namespace Stockfish::Eval::NNUE {
 
-  // Version of the evaluation file
-  constexpr std::uint32_t Version = 0x7AF32F20u;
-
-  // Constant used in evaluation value calculation
-  constexpr int OutputScale = 16;
-  constexpr int WeightScaleBits = 6;
-
-  // Size of cache line (in bytes)
-  constexpr std::size_t CacheLineSize = 64;
-
-  // SIMD width (in bytes)
-  #if defined(USE_AVX2)
-  constexpr std::size_t SimdWidth = 32;
-
-  #elif defined(USE_SSE2)
-  constexpr std::size_t SimdWidth = 16;
-
-  #elif defined(USE_MMX)
-  constexpr std::size_t SimdWidth = 8;
-
-  #elif defined(USE_NEON)
-  constexpr std::size_t SimdWidth = 16;
-  #endif
-
-  constexpr std::size_t MaxSimdWidth = 32;
-
-  // Type of input feature after conversion
-  using TransformedFeatureType = std::uint8_t;
-  using IndexType = std::uint32_t;
-
-  // Round n up to be a multiple of base
-  template <typename IntType>
-  constexpr IntType ceil_to_multiple(IntType n, IntType base) {
-      return (n + base - 1) / base * base;
-  }
-
-  // read_little_endian() is our utility to read an integer (signed or unsigned, any size)
-  // from a stream in little-endian order. We swap the byte order after the read if
-  // necessary to return a result with the byte ordering of the compiling machine.
-  template <typename IntType>
-  inline IntType read_little_endian(std::istream& stream) {
-      IntType result;
-
-      if (IsLittleEndian)
-          stream.read(reinterpret_cast<char*>(&result), sizeof(IntType));
-      else
-      {
-          std::uint8_t u[sizeof(IntType)];
-          typename std::make_unsigned<IntType>::type v = 0;
-
-          stream.read(reinterpret_cast<char*>(u), sizeof(IntType));
-          for (std::size_t i = 0; i < sizeof(IntType); ++i)
-              v = (v << 8) | u[sizeof(IntType) - i - 1];
-
-          std::memcpy(&result, &v, sizeof(IntType));
-      }
-
-      return result;
-  }
-
-  // write_little_endian() is our utility to write an integer (signed or unsigned, any size)
-  // to a stream in little-endian order. We swap the byte order before the write if
-  // necessary to always write in little endian order, independantly of the byte
-  // ordering of the compiling machine.
-  template <typename IntType>
-  inline void write_little_endian(std::ostream& stream, IntType value) {
-
-      if (IsLittleEndian)
-          stream.write(reinterpret_cast<const char*>(&value), sizeof(IntType));
-      else
-      {
-          std::uint8_t u[sizeof(IntType)];
-          typename std::make_unsigned<IntType>::type v = value;
-
-          std::size_t i = 0;
-          // if constexpr to silence the warning about shift by 8
-          if constexpr (sizeof(IntType) > 1)
-          {
+// Version of the evaluation file
+constexpr std::uint32_t Version = 0x7AF32F20u;
+
+// Constant used in evaluation value calculation
+constexpr int OutputScale     = 16;
+constexpr int WeightScaleBits = 6;
+
+// 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;
+
+#elif defined(USE_SSE2)
+constexpr std::size_t SimdWidth = 16;
+
+#elif defined(USE_NEON)
+constexpr std::size_t SimdWidth = 16;
+#endif
+
+constexpr std::size_t MaxSimdWidth = 32;
+
+// Type of input feature after conversion
+using TransformedFeatureType = std::uint8_t;
+using IndexType              = std::uint32_t;
+
+// Round n up to be a multiple of base
+template<typename IntType>
+constexpr IntType ceil_to_multiple(IntType n, IntType base) {
+    return (n + base - 1) / base * base;
+}
+
+
+// Utility to read an integer (signed or unsigned, any size)
+// from a stream in little-endian order. We swap the byte order after the read if
+// necessary to return a result with the byte ordering of the compiling machine.
+template<typename IntType>
+inline IntType read_little_endian(std::istream& stream) {
+    IntType result;
+
+    if (IsLittleEndian)
+        stream.read(reinterpret_cast<char*>(&result), sizeof(IntType));
+    else
+    {
+        std::uint8_t                  u[sizeof(IntType)];
+        std::make_unsigned_t<IntType> v = 0;
+
+        stream.read(reinterpret_cast<char*>(u), sizeof(IntType));
+        for (std::size_t i = 0; i < sizeof(IntType); ++i)
+            v = (v << 8) | u[sizeof(IntType) - i - 1];
+
+        std::memcpy(&result, &v, sizeof(IntType));
+    }
+
+    return result;
+}
+
+
+// Utility to write an integer (signed or unsigned, any size)
+// to a stream in little-endian order. We swap the byte order before the write if
+// necessary to always write in little endian order, independently of the byte
+// ordering of the compiling machine.
+template<typename IntType>
+inline void write_little_endian(std::ostream& stream, IntType value) {
+
+    if (IsLittleEndian)
+        stream.write(reinterpret_cast<const char*>(&value), sizeof(IntType));
+    else
+    {
+        std::uint8_t                  u[sizeof(IntType)];
+        std::make_unsigned_t<IntType> v = value;
+
+        std::size_t i = 0;
+        // if constexpr to silence the warning about shift by 8
+        if constexpr (sizeof(IntType) > 1)
+        {
             for (; i + 1 < sizeof(IntType); ++i)
             {
-                u[i] = v;
+                u[i] = std::uint8_t(v);
                 v >>= 8;
             }
-          }
-          u[i] = v;
-
-          stream.write(reinterpret_cast<char*>(u), sizeof(IntType));
-      }
-  }
-
-  // read_little_endian(s, out, N) : read integers in bulk from a little indian stream.
-  // This reads N integers from stream s and put them in array out.
-  template <typename IntType>
-  inline void read_little_endian(std::istream& stream, IntType* out, std::size_t count) {
-      if (IsLittleEndian)
-          stream.read(reinterpret_cast<char*>(out), sizeof(IntType) * count);
-      else
-          for (std::size_t i = 0; i < count; ++i)
-              out[i] = read_little_endian<IntType>(stream);
-  }
-
-  // write_little_endian(s, out, N) : write integers in bulk to a little indian stream.
-  // This takes N integers from array values and writes them on stream s.
-  template <typename IntType>
-  inline void write_little_endian(std::ostream& stream, const IntType* values, std::size_t count) {
-      if (IsLittleEndian)
-          stream.write(reinterpret_cast<const char*>(values), sizeof(IntType) * count);
-      else
-          for (std::size_t i = 0; i < count; ++i)
-              write_little_endian<IntType>(stream, values[i]);
-  }
+        }
+        u[i] = std::uint8_t(v);
+
+        stream.write(reinterpret_cast<char*>(u), sizeof(IntType));
+    }
+}
+
+
+// Read integers in bulk from a little indian stream.
+// This reads N integers from stream s and put them in array out.
+template<typename IntType>
+inline void read_little_endian(std::istream& stream, IntType* out, std::size_t count) {
+    if (IsLittleEndian)
+        stream.read(reinterpret_cast<char*>(out), sizeof(IntType) * count);
+    else
+        for (std::size_t i = 0; i < count; ++i)
+            out[i] = read_little_endian<IntType>(stream);
+}
+
+
+// Write integers in bulk to a little indian stream.
+// This takes N integers from array values and writes them on stream s.
+template<typename IntType>
+inline void write_little_endian(std::ostream& stream, const IntType* values, std::size_t count) {
+    if (IsLittleEndian)
+        stream.write(reinterpret_cast<const char*>(values), sizeof(IntType) * count);
+    else
+        for (std::size_t i = 0; i < count; ++i)
+            write_little_endian<IntType>(stream, values[i]);
+}
+
+
+// Read N signed integers from the stream s, putting them in
+// the array out. The stream is assumed to be compressed using the signed LEB128 format.
+// See https://en.wikipedia.org/wiki/LEB128 for a description of the compression scheme.
+template<typename IntType>
+inline void read_leb_128(std::istream& stream, IntType* out, std::size_t count) {
+
+    // Check the presence of our LEB128 magic string
+    char leb128MagicString[Leb128MagicStringSize];
+    stream.read(leb128MagicString, Leb128MagicStringSize);
+    assert(strncmp(Leb128MagicString, leb128MagicString, Leb128MagicStringSize) == 0);
+
+    static_assert(std::is_signed_v<IntType>, "Not implemented for unsigned types");
+
+    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);
+}
+
+
+// Write signed integers to a stream with LEB128 compression.
+// This takes N integers from array values, compress them with the LEB128 algorithm and
+// writes the result on the stream s.
+// See https://en.wikipedia.org/wiki/LEB128 for a description of the compression scheme.
+template<typename IntType>
+inline void write_leb_128(std::ostream& stream, const IntType* values, std::size_t count) {
+
+    // Write our LEB128 magic string
+    stream.write(Leb128MagicString, Leb128MagicStringSize);
+
+    static_assert(std::is_signed_v<IntType>, "Not implemented for unsigned types");
+
+    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
+#endif  // #ifndef NNUE_COMMON_H_INCLUDED