1
0
Fork 0
stockfish/src/nnue/layers/affine_transform.h

465 lines
19 KiB
C++

/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2021 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
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Stockfish is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
// Definition of layer AffineTransform of NNUE evaluation function
#ifndef NNUE_LAYERS_AFFINE_TRANSFORM_H_INCLUDED
#define NNUE_LAYERS_AFFINE_TRANSFORM_H_INCLUDED
#include <iostream>
#include "../nnue_common.h"
namespace Stockfish::Eval::NNUE::Layers {
// Affine transformation layer
template <typename PreviousLayer, IndexType OutDims>
class AffineTransform {
public:
// Input/output type
using InputType = typename PreviousLayer::OutputType;
using OutputType = std::int32_t;
static_assert(std::is_same<InputType, std::uint8_t>::value, "");
// Number of input/output dimensions
static constexpr IndexType InputDimensions =
PreviousLayer::OutputDimensions;
static constexpr IndexType OutputDimensions = OutDims;
static constexpr IndexType PaddedInputDimensions =
ceil_to_multiple<IndexType>(InputDimensions, MaxSimdWidth);
#if defined (USE_AVX512)
static constexpr const IndexType OutputSimdWidth = SimdWidth / 2;
#elif defined (USE_SSSE3)
static constexpr const IndexType OutputSimdWidth = SimdWidth / 4;
#endif
// Size of forward propagation buffer used in this layer
static constexpr std::size_t SelfBufferSize =
ceil_to_multiple(OutputDimensions * sizeof(OutputType), CacheLineSize);
// Size of the forward propagation buffer used from the input layer to this layer
static constexpr std::size_t BufferSize =
PreviousLayer::BufferSize + SelfBufferSize;
// Hash value embedded in the evaluation file
static constexpr std::uint32_t get_hash_value() {
std::uint32_t hashValue = 0xCC03DAE4u;
hashValue += OutputDimensions;
hashValue ^= PreviousLayer::get_hash_value() >> 1;
hashValue ^= PreviousLayer::get_hash_value() << 31;
return hashValue;
}
// Read network parameters
bool read_parameters(std::istream& stream) {
if (!previousLayer.read_parameters(stream)) return false;
for (std::size_t i = 0; i < OutputDimensions; ++i)
biases[i] = read_little_endian<BiasType>(stream);
for (std::size_t i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
#if !defined (USE_SSSE3)
weights[i] = read_little_endian<WeightType>(stream);
#else
weights[
(i / 4) % (PaddedInputDimensions / 4) * OutputDimensions * 4 +
i / PaddedInputDimensions * 4 +
i % 4
] = read_little_endian<WeightType>(stream);
// Determine if eights of weight and input products can be summed using 16bits
// without saturation. We assume worst case combinations of 0 and 127 for all inputs.
if (OutputDimensions > 1 && !stream.fail())
{
canSaturate16.count = 0;
#if !defined(USE_VNNI)
for (IndexType i = 0; i < PaddedInputDimensions; i += 16)
for (IndexType j = 0; j < OutputDimensions; ++j)
for (int x = 0; x < 2; ++x)
{
WeightType* w = &weights[i * OutputDimensions + j * 4 + x * 2];
int sum[2] = {0, 0};
for (int k = 0; k < 8; ++k)
{
IndexType idx = k / 2 * OutputDimensions * 4 + k % 2;
sum[w[idx] < 0] += w[idx];
}
for (int sign : { -1, 1 })
while (sign * sum[sign == -1] > 258)
{
int maxK = 0, maxW = 0;
for (int k = 0; k < 8; ++k)
{
IndexType idx = k / 2 * OutputDimensions * 4 + k % 2;
if (maxW < sign * w[idx])
maxK = k, maxW = sign * w[idx];
}
IndexType idx = maxK / 2 * OutputDimensions * 4 + maxK % 2;
sum[sign == -1] -= w[idx];
canSaturate16.add(j, i + maxK / 2 * 4 + maxK % 2 + x * 2, w[idx]);
w[idx] = 0;
}
}
// Non functional optimization for faster more linear access
std::sort(canSaturate16.ids, canSaturate16.ids + canSaturate16.count,
[](const typename CanSaturate::Entry& e1, const typename CanSaturate::Entry& e2)
{ return e1.in == e2.in ? e1.out < e2.out : e1.in < e2.in; });
#endif
}
#endif
return !stream.fail();
}
// Forward propagation
const OutputType* propagate(
const TransformedFeatureType* transformedFeatures, char* buffer) const {
const auto input = previousLayer.propagate(
transformedFeatures, buffer + SelfBufferSize);
#if defined (USE_AVX512)
[[maybe_unused]] const __m512i Ones512 = _mm512_set1_epi16(1);
[[maybe_unused]] auto m512_hadd = [](__m512i sum, int bias) -> int {
return _mm512_reduce_add_epi32(sum) + bias;
};
[[maybe_unused]] auto m512_add_dpbusd_epi32 = [=](__m512i& acc, __m512i a, __m512i b) {
#if defined (USE_VNNI)
acc = _mm512_dpbusd_epi32(acc, a, b);
#else
__m512i product0 = _mm512_maddubs_epi16(a, b);
product0 = _mm512_madd_epi16(product0, Ones512);
acc = _mm512_add_epi32(acc, product0);
#endif
};
[[maybe_unused]] auto m512_add_dpbusd_epi32x4 = [=](__m512i& acc, __m512i a0, __m512i b0, __m512i a1, __m512i b1,
__m512i a2, __m512i b2, __m512i a3, __m512i b3) {
#if defined (USE_VNNI)
acc = _mm512_dpbusd_epi32(acc, a0, b0);
acc = _mm512_dpbusd_epi32(acc, a1, b1);
acc = _mm512_dpbusd_epi32(acc, a2, b2);
acc = _mm512_dpbusd_epi32(acc, a3, b3);
#else
__m512i product0 = _mm512_maddubs_epi16(a0, b0);
__m512i product1 = _mm512_maddubs_epi16(a1, b1);
__m512i product2 = _mm512_maddubs_epi16(a2, b2);
__m512i product3 = _mm512_maddubs_epi16(a3, b3);
product0 = _mm512_add_epi16(product0, product1);
product2 = _mm512_add_epi16(product2, product3);
product0 = _mm512_add_epi16(product0, product2);
product0 = _mm512_madd_epi16(product0, Ones512);
acc = _mm512_add_epi32(acc, product0);
#endif
};
#endif
#if defined (USE_AVX2)
[[maybe_unused]] const __m256i Ones256 = _mm256_set1_epi16(1);
[[maybe_unused]] auto m256_hadd = [](__m256i sum, int bias) -> int {
__m128i sum128 = _mm_add_epi32(_mm256_castsi256_si128(sum), _mm256_extracti128_si256(sum, 1));
sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_BADC));
sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_CDAB));
return _mm_cvtsi128_si32(sum128) + bias;
};
[[maybe_unused]] auto m256_add_dpbusd_epi32 = [=](__m256i& acc, __m256i a, __m256i b) {
#if defined (USE_VNNI)
acc = _mm256_dpbusd_epi32(acc, a, b);
#else
__m256i product0 = _mm256_maddubs_epi16(a, b);
product0 = _mm256_madd_epi16(product0, Ones256);
acc = _mm256_add_epi32(acc, product0);
#endif
};
[[maybe_unused]] auto m256_add_dpbusd_epi32x4 = [=](__m256i& acc, __m256i a0, __m256i b0, __m256i a1, __m256i b1,
__m256i a2, __m256i b2, __m256i a3, __m256i b3) {
#if defined (USE_VNNI)
acc = _mm256_dpbusd_epi32(acc, a0, b0);
acc = _mm256_dpbusd_epi32(acc, a1, b1);
acc = _mm256_dpbusd_epi32(acc, a2, b2);
acc = _mm256_dpbusd_epi32(acc, a3, b3);
#else
__m256i product0 = _mm256_maddubs_epi16(a0, b0);
__m256i product1 = _mm256_maddubs_epi16(a1, b1);
__m256i product2 = _mm256_maddubs_epi16(a2, b2);
__m256i product3 = _mm256_maddubs_epi16(a3, b3);
product0 = _mm256_add_epi16(product0, product1);
product2 = _mm256_add_epi16(product2, product3);
product0 = _mm256_add_epi16(product0, product2);
product0 = _mm256_madd_epi16(product0, Ones256);
acc = _mm256_add_epi32(acc, product0);
#endif
};
#endif
#if defined (USE_SSSE3)
[[maybe_unused]] const __m128i Ones128 = _mm_set1_epi16(1);
[[maybe_unused]] auto m128_hadd = [](__m128i sum, int bias) -> int {
sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0x4E)); //_MM_PERM_BADC
sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0xB1)); //_MM_PERM_CDAB
return _mm_cvtsi128_si32(sum) + bias;
};
[[maybe_unused]] auto m128_add_dpbusd_epi32 = [=](__m128i& acc, __m128i a, __m128i b) {
__m128i product0 = _mm_maddubs_epi16(a, b);
product0 = _mm_madd_epi16(product0, Ones128);
acc = _mm_add_epi32(acc, product0);
};
[[maybe_unused]] auto m128_add_dpbusd_epi32x4 = [=](__m128i& acc, __m128i a0, __m128i b0, __m128i a1, __m128i b1,
__m128i a2, __m128i b2, __m128i a3, __m128i b3) {
__m128i product0 = _mm_maddubs_epi16(a0, b0);
__m128i product1 = _mm_maddubs_epi16(a1, b1);
__m128i product2 = _mm_maddubs_epi16(a2, b2);
__m128i product3 = _mm_maddubs_epi16(a3, b3);
product0 = _mm_add_epi16(product0, product1);
product2 = _mm_add_epi16(product2, product3);
product0 = _mm_add_epi16(product0, product2);
product0 = _mm_madd_epi16(product0, Ones128);
acc = _mm_add_epi32(acc, product0);
};
#endif
#if defined (USE_AVX512)
using vec_t = __m512i;
#define vec_setzero _mm512_setzero_si512
#define vec_set_32 _mm512_set1_epi32
auto& vec_add_dpbusd_32 = m512_add_dpbusd_epi32;
auto& vec_add_dpbusd_32x4 = m512_add_dpbusd_epi32x4;
auto& vec_hadd = m512_hadd;
#elif defined (USE_AVX2)
using vec_t = __m256i;
#define vec_setzero _mm256_setzero_si256
#define vec_set_32 _mm256_set1_epi32
auto& vec_add_dpbusd_32 = m256_add_dpbusd_epi32;
auto& vec_add_dpbusd_32x4 = m256_add_dpbusd_epi32x4;
auto& vec_hadd = m256_hadd;
#elif defined (USE_SSSE3)
using vec_t = __m128i;
#define vec_setzero _mm_setzero_si128
#define vec_set_32 _mm_set1_epi32
auto& vec_add_dpbusd_32 = m128_add_dpbusd_epi32;
auto& vec_add_dpbusd_32x4 = m128_add_dpbusd_epi32x4;
auto& vec_hadd = m128_hadd;
#endif
#if defined (USE_SSSE3)
const auto output = reinterpret_cast<OutputType*>(buffer);
const auto inputVector = reinterpret_cast<const vec_t*>(input);
static_assert(OutputDimensions % OutputSimdWidth == 0 || OutputDimensions == 1);
// OutputDimensions is either 1 or a multiple of SimdWidth
// because then it is also an input dimension.
if constexpr (OutputDimensions % OutputSimdWidth == 0)
{
constexpr IndexType NumChunks = PaddedInputDimensions / 4;
const auto input32 = reinterpret_cast<const std::int32_t*>(input);
vec_t* outptr = reinterpret_cast<vec_t*>(output);
std::memcpy(output, biases, OutputDimensions * sizeof(OutputType));
for (int i = 0; i < (int)NumChunks - 3; i += 4)
{
const vec_t in0 = vec_set_32(input32[i + 0]);
const vec_t in1 = vec_set_32(input32[i + 1]);
const vec_t in2 = vec_set_32(input32[i + 2]);
const vec_t in3 = vec_set_32(input32[i + 3]);
const auto col0 = reinterpret_cast<const vec_t*>(&weights[(i + 0) * OutputDimensions * 4]);
const auto col1 = reinterpret_cast<const vec_t*>(&weights[(i + 1) * OutputDimensions * 4]);
const auto col2 = reinterpret_cast<const vec_t*>(&weights[(i + 2) * OutputDimensions * 4]);
const auto col3 = reinterpret_cast<const vec_t*>(&weights[(i + 3) * OutputDimensions * 4]);
for (int j = 0; j * OutputSimdWidth < OutputDimensions; ++j)
vec_add_dpbusd_32x4(outptr[j], in0, col0[j], in1, col1[j], in2, col2[j], in3, col3[j]);
}
for (int i = 0; i < canSaturate16.count; ++i)
output[canSaturate16.ids[i].out] += input[canSaturate16.ids[i].in] * canSaturate16.ids[i].w;
}
else if constexpr (OutputDimensions == 1)
{
#if defined (USE_AVX512)
if constexpr (PaddedInputDimensions % (SimdWidth * 2) != 0)
{
constexpr IndexType NumChunks = PaddedInputDimensions / SimdWidth;
const auto inputVector256 = reinterpret_cast<const __m256i*>(input);
__m256i sum0 = _mm256_setzero_si256();
const auto row0 = reinterpret_cast<const __m256i*>(&weights[0]);
for (int j = 0; j < (int)NumChunks; ++j)
{
const __m256i in = inputVector256[j];
m256_add_dpbusd_epi32(sum0, in, row0[j]);
}
output[0] = m256_hadd(sum0, biases[0]);
}
else
#endif
{
#if defined (USE_AVX512)
constexpr IndexType NumChunks = PaddedInputDimensions / (SimdWidth * 2);
#else
constexpr IndexType NumChunks = PaddedInputDimensions / SimdWidth;
#endif
vec_t sum0 = vec_setzero();
const auto row0 = reinterpret_cast<const vec_t*>(&weights[0]);
for (int j = 0; j < (int)NumChunks; ++j)
{
const vec_t in = inputVector[j];
vec_add_dpbusd_32(sum0, in, row0[j]);
}
output[0] = vec_hadd(sum0, biases[0]);
}
}
#else
// Use old implementation for the other architectures.
auto output = reinterpret_cast<OutputType*>(buffer);
#if defined(USE_SSE2)
constexpr IndexType NumChunks = PaddedInputDimensions / SimdWidth;
const __m128i Zeros = _mm_setzero_si128();
const auto inputVector = reinterpret_cast<const __m128i*>(input);
#elif defined(USE_MMX)
constexpr IndexType NumChunks = PaddedInputDimensions / SimdWidth;
const __m64 Zeros = _mm_setzero_si64();
const auto inputVector = reinterpret_cast<const __m64*>(input);
#elif defined(USE_NEON)
constexpr IndexType NumChunks = PaddedInputDimensions / SimdWidth;
const auto inputVector = reinterpret_cast<const int8x8_t*>(input);
#endif
for (IndexType i = 0; i < OutputDimensions; ++i) {
const IndexType offset = i * PaddedInputDimensions;
#if defined(USE_SSE2)
__m128i sumLo = _mm_cvtsi32_si128(biases[i]);
__m128i sumHi = Zeros;
const auto row = reinterpret_cast<const __m128i*>(&weights[offset]);
for (IndexType j = 0; j < NumChunks; ++j) {
__m128i row_j = _mm_load_si128(&row[j]);
__m128i input_j = _mm_load_si128(&inputVector[j]);
__m128i extendedRowLo = _mm_srai_epi16(_mm_unpacklo_epi8(row_j, row_j), 8);
__m128i extendedRowHi = _mm_srai_epi16(_mm_unpackhi_epi8(row_j, row_j), 8);
__m128i extendedInputLo = _mm_unpacklo_epi8(input_j, Zeros);
__m128i extendedInputHi = _mm_unpackhi_epi8(input_j, Zeros);
__m128i productLo = _mm_madd_epi16(extendedRowLo, extendedInputLo);
__m128i productHi = _mm_madd_epi16(extendedRowHi, extendedInputHi);
sumLo = _mm_add_epi32(sumLo, productLo);
sumHi = _mm_add_epi32(sumHi, productHi);
}
__m128i sum = _mm_add_epi32(sumLo, sumHi);
__m128i sumHigh_64 = _mm_shuffle_epi32(sum, _MM_SHUFFLE(1, 0, 3, 2));
sum = _mm_add_epi32(sum, sumHigh_64);
__m128i sum_second_32 = _mm_shufflelo_epi16(sum, _MM_SHUFFLE(1, 0, 3, 2));
sum = _mm_add_epi32(sum, sum_second_32);
output[i] = _mm_cvtsi128_si32(sum);
#elif defined(USE_MMX)
__m64 sumLo = _mm_cvtsi32_si64(biases[i]);
__m64 sumHi = Zeros;
const auto row = reinterpret_cast<const __m64*>(&weights[offset]);
for (IndexType j = 0; j < NumChunks; ++j) {
__m64 row_j = row[j];
__m64 input_j = inputVector[j];
__m64 extendedRowLo = _mm_srai_pi16(_mm_unpacklo_pi8(row_j, row_j), 8);
__m64 extendedRowHi = _mm_srai_pi16(_mm_unpackhi_pi8(row_j, row_j), 8);
__m64 extendedInputLo = _mm_unpacklo_pi8(input_j, Zeros);
__m64 extendedInputHi = _mm_unpackhi_pi8(input_j, Zeros);
__m64 productLo = _mm_madd_pi16(extendedRowLo, extendedInputLo);
__m64 productHi = _mm_madd_pi16(extendedRowHi, extendedInputHi);
sumLo = _mm_add_pi32(sumLo, productLo);
sumHi = _mm_add_pi32(sumHi, productHi);
}
__m64 sum = _mm_add_pi32(sumLo, sumHi);
sum = _mm_add_pi32(sum, _mm_unpackhi_pi32(sum, sum));
output[i] = _mm_cvtsi64_si32(sum);
#elif defined(USE_NEON)
int32x4_t sum = {biases[i]};
const auto row = reinterpret_cast<const int8x8_t*>(&weights[offset]);
for (IndexType j = 0; j < NumChunks; ++j) {
int16x8_t product = vmull_s8(inputVector[j * 2], row[j * 2]);
product = vmlal_s8(product, inputVector[j * 2 + 1], row[j * 2 + 1]);
sum = vpadalq_s16(sum, product);
}
output[i] = sum[0] + sum[1] + sum[2] + sum[3];
#else
OutputType sum = biases[i];
for (IndexType j = 0; j < InputDimensions; ++j) {
sum += weights[offset + j] * input[j];
}
output[i] = sum;
#endif
}
#if defined(USE_MMX)
_mm_empty();
#endif
#endif
return output;
}
private:
using BiasType = OutputType;
using WeightType = std::int8_t;
PreviousLayer previousLayer;
alignas(CacheLineSize) BiasType biases[OutputDimensions];
alignas(CacheLineSize) WeightType weights[OutputDimensions * PaddedInputDimensions];
#if defined (USE_SSSE3)
struct CanSaturate {
int count;
struct Entry {
uint16_t out;
uint16_t in;
int8_t w;
} ids[PaddedInputDimensions * OutputDimensions * 3 / 4];
void add(int i, int j, int8_t w) {
ids[count].out = i;
ids[count].in = j;
ids[count].w = w;
++count;
}
} canSaturate16;
#endif
};
} // namespace Stockfish::Eval::NNUE::Layers
#endif // #ifndef NNUE_LAYERS_AFFINE_TRANSFORM_H_INCLUDED