2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
5 Stockfish is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, either version 3 of the License, or
8 (at your option) any later version.
10 Stockfish is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
19 // Constants used in NNUE evaluation function
21 #ifndef NNUE_COMMON_H_INCLUDED
22 #define NNUE_COMMON_H_INCLUDED
28 #include <immintrin.h>
30 #elif defined(USE_SSE41)
31 #include <smmintrin.h>
33 #elif defined(USE_SSSE3)
34 #include <tmmintrin.h>
36 #elif defined(USE_SSE2)
37 #include <emmintrin.h>
39 #elif defined(USE_MMX)
42 #elif defined(USE_NEON)
46 // HACK: Use _mm256_loadu_si256() instead of _mm256_load_si256. Otherwise a binary
47 // compiled with older g++ crashes because the output memory is not aligned
48 // even though alignas is specified.
50 #if defined(__GNUC__ ) && (__GNUC__ < 9) && defined(_WIN32)
51 #define _mm256_loadA_si256 _mm256_loadu_si256
52 #define _mm256_storeA_si256 _mm256_storeu_si256
54 #define _mm256_loadA_si256 _mm256_load_si256
55 #define _mm256_storeA_si256 _mm256_store_si256
59 #if defined(USE_AVX512)
60 #if defined(__GNUC__ ) && (__GNUC__ < 9) && defined(_WIN32)
61 #define _mm512_loadA_si512 _mm512_loadu_si512
62 #define _mm512_storeA_si512 _mm512_storeu_si512
64 #define _mm512_loadA_si512 _mm512_load_si512
65 #define _mm512_storeA_si512 _mm512_store_si512
69 namespace Eval::NNUE {
71 // Version of the evaluation file
72 constexpr std::uint32_t kVersion = 0x7AF32F16u;
74 // Constant used in evaluation value calculation
75 constexpr int FV_SCALE = 16;
76 constexpr int kWeightScaleBits = 6;
78 // Size of cache line (in bytes)
79 constexpr std::size_t kCacheLineSize = 64;
81 // SIMD width (in bytes)
83 constexpr std::size_t kSimdWidth = 32;
85 #elif defined(USE_SSE2)
86 constexpr std::size_t kSimdWidth = 16;
88 #elif defined(USE_MMX)
89 constexpr std::size_t kSimdWidth = 8;
91 #elif defined(USE_NEON)
92 constexpr std::size_t kSimdWidth = 16;
95 constexpr std::size_t kMaxSimdWidth = 32;
97 // Type of input feature after conversion
98 using TransformedFeatureType = std::uint8_t;
99 using IndexType = std::uint32_t;
101 // Round n up to be a multiple of base
102 template <typename IntType>
103 constexpr IntType CeilToMultiple(IntType n, IntType base) {
104 return (n + base - 1) / base * base;
107 // read_little_endian() is our utility to read an integer (signed or unsigned, any size)
108 // from a stream in little-endian order. We swap the byte order after the read if
109 // necessary to return a result with the byte ordering of the compiling machine.
110 template <typename IntType>
111 inline IntType read_little_endian(std::istream& stream) {
114 std::uint8_t u[sizeof(IntType)];
115 typename std::make_unsigned<IntType>::type v = 0;
117 stream.read(reinterpret_cast<char*>(u), sizeof(IntType));
118 for (std::size_t i = 0; i < sizeof(IntType); ++i)
119 v = (v << 8) | u[sizeof(IntType) - i - 1];
121 std::memcpy(&result, &v, sizeof(IntType));
125 } // namespace Eval::NNUE
127 #endif // #ifndef NNUE_COMMON_H_INCLUDED