2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2022 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 // A class that converts the input features of the NNUE evaluation function
21 #ifndef NNUE_FEATURE_TRANSFORMER_H_INCLUDED
22 #define NNUE_FEATURE_TRANSFORMER_H_INCLUDED
24 #include "nnue_common.h"
25 #include "nnue_architecture.h"
27 #include <cstring> // std::memset()
29 namespace Stockfish::Eval::NNUE {
31 using BiasType = std::int16_t;
32 using WeightType = std::int16_t;
33 using PSQTWeightType = std::int32_t;
35 // If vector instructions are enabled, we update and refresh the
36 // accumulator tile by tile such that each tile fits in the CPU's
40 static_assert(PSQTBuckets % 8 == 0,
41 "Per feature PSQT values cannot be processed at granularity lower than 8 at a time.");
44 typedef __m512i vec_t;
45 typedef __m256i psqt_vec_t;
46 #define vec_load(a) _mm512_load_si512(a)
47 #define vec_store(a,b) _mm512_store_si512(a,b)
48 #define vec_add_16(a,b) _mm512_add_epi16(a,b)
49 #define vec_sub_16(a,b) _mm512_sub_epi16(a,b)
50 #define vec_load_psqt(a) _mm256_load_si256(a)
51 #define vec_store_psqt(a,b) _mm256_store_si256(a,b)
52 #define vec_add_psqt_32(a,b) _mm256_add_epi32(a,b)
53 #define vec_sub_psqt_32(a,b) _mm256_sub_epi32(a,b)
54 #define vec_zero_psqt() _mm256_setzero_si256()
55 #define NumRegistersSIMD 32
58 typedef __m256i vec_t;
59 typedef __m256i psqt_vec_t;
60 #define vec_load(a) _mm256_load_si256(a)
61 #define vec_store(a,b) _mm256_store_si256(a,b)
62 #define vec_add_16(a,b) _mm256_add_epi16(a,b)
63 #define vec_sub_16(a,b) _mm256_sub_epi16(a,b)
64 #define vec_load_psqt(a) _mm256_load_si256(a)
65 #define vec_store_psqt(a,b) _mm256_store_si256(a,b)
66 #define vec_add_psqt_32(a,b) _mm256_add_epi32(a,b)
67 #define vec_sub_psqt_32(a,b) _mm256_sub_epi32(a,b)
68 #define vec_zero_psqt() _mm256_setzero_si256()
69 #define NumRegistersSIMD 16
72 typedef __m128i vec_t;
73 typedef __m128i psqt_vec_t;
74 #define vec_load(a) (*(a))
75 #define vec_store(a,b) *(a)=(b)
76 #define vec_add_16(a,b) _mm_add_epi16(a,b)
77 #define vec_sub_16(a,b) _mm_sub_epi16(a,b)
78 #define vec_load_psqt(a) (*(a))
79 #define vec_store_psqt(a,b) *(a)=(b)
80 #define vec_add_psqt_32(a,b) _mm_add_epi32(a,b)
81 #define vec_sub_psqt_32(a,b) _mm_sub_epi32(a,b)
82 #define vec_zero_psqt() _mm_setzero_si128()
83 #define NumRegistersSIMD (Is64Bit ? 16 : 8)
87 typedef __m64 psqt_vec_t;
88 #define vec_load(a) (*(a))
89 #define vec_store(a,b) *(a)=(b)
90 #define vec_add_16(a,b) _mm_add_pi16(a,b)
91 #define vec_sub_16(a,b) _mm_sub_pi16(a,b)
92 #define vec_load_psqt(a) (*(a))
93 #define vec_store_psqt(a,b) *(a)=(b)
94 #define vec_add_psqt_32(a,b) _mm_add_pi32(a,b)
95 #define vec_sub_psqt_32(a,b) _mm_sub_pi32(a,b)
96 #define vec_zero_psqt() _mm_setzero_si64()
97 #define NumRegistersSIMD 8
100 typedef int16x8_t vec_t;
101 typedef int32x4_t psqt_vec_t;
102 #define vec_load(a) (*(a))
103 #define vec_store(a,b) *(a)=(b)
104 #define vec_add_16(a,b) vaddq_s16(a,b)
105 #define vec_sub_16(a,b) vsubq_s16(a,b)
106 #define vec_load_psqt(a) (*(a))
107 #define vec_store_psqt(a,b) *(a)=(b)
108 #define vec_add_psqt_32(a,b) vaddq_s32(a,b)
109 #define vec_sub_psqt_32(a,b) vsubq_s32(a,b)
110 #define vec_zero_psqt() psqt_vec_t{0}
111 #define NumRegistersSIMD 16
121 // Compute optimal SIMD register count for feature transformer accumulation.
123 // We use __m* types as template arguments, which causes GCC to emit warnings
124 // about losing some attribute information. This is irrelevant to us as we
125 // only take their size, so the following pragma are harmless.
126 #pragma GCC diagnostic push
127 #pragma GCC diagnostic ignored "-Wignored-attributes"
129 template <typename SIMDRegisterType,
133 static constexpr int BestRegisterCount()
135 #define RegisterSize sizeof(SIMDRegisterType)
136 #define LaneSize sizeof(LaneType)
138 static_assert(RegisterSize >= LaneSize);
139 static_assert(MaxRegisters <= NumRegistersSIMD);
140 static_assert(MaxRegisters > 0);
141 static_assert(NumRegistersSIMD > 0);
142 static_assert(RegisterSize % LaneSize == 0);
143 static_assert((NumLanes * LaneSize) % RegisterSize == 0);
145 const int ideal = (NumLanes * LaneSize) / RegisterSize;
146 if (ideal <= MaxRegisters)
149 // Look for the largest divisor of the ideal register count that is smaller than MaxRegisters
150 for (int divisor = MaxRegisters; divisor > 1; --divisor)
151 if (ideal % divisor == 0)
157 static constexpr int NumRegs = BestRegisterCount<vec_t, WeightType, TransformedFeatureDimensions, NumRegistersSIMD>();
158 static constexpr int NumPsqtRegs = BestRegisterCount<psqt_vec_t, PSQTWeightType, PSQTBuckets, NumRegistersSIMD>();
160 #pragma GCC diagnostic pop
166 // Input feature converter
167 class FeatureTransformer {
170 // Number of output dimensions for one side
171 static constexpr IndexType HalfDimensions = TransformedFeatureDimensions;
174 static constexpr IndexType TileHeight = NumRegs * sizeof(vec_t) / 2;
175 static constexpr IndexType PsqtTileHeight = NumPsqtRegs * sizeof(psqt_vec_t) / 4;
176 static_assert(HalfDimensions % TileHeight == 0, "TileHeight must divide HalfDimensions");
177 static_assert(PSQTBuckets % PsqtTileHeight == 0, "PsqtTileHeight must divide PSQTBuckets");
182 using OutputType = TransformedFeatureType;
184 // Number of input/output dimensions
185 static constexpr IndexType InputDimensions = FeatureSet::Dimensions;
186 static constexpr IndexType OutputDimensions = HalfDimensions;
188 // Size of forward propagation buffer
189 static constexpr std::size_t BufferSize =
190 OutputDimensions * sizeof(OutputType);
192 // Hash value embedded in the evaluation file
193 static constexpr std::uint32_t get_hash_value() {
194 return FeatureSet::HashValue ^ (OutputDimensions * 2);
197 // Read network parameters
198 bool read_parameters(std::istream& stream) {
200 read_little_endian<BiasType >(stream, biases , HalfDimensions );
201 read_little_endian<WeightType >(stream, weights , HalfDimensions * InputDimensions);
202 read_little_endian<PSQTWeightType>(stream, psqtWeights, PSQTBuckets * InputDimensions);
204 return !stream.fail();
207 // Write network parameters
208 bool write_parameters(std::ostream& stream) const {
210 write_little_endian<BiasType >(stream, biases , HalfDimensions );
211 write_little_endian<WeightType >(stream, weights , HalfDimensions * InputDimensions);
212 write_little_endian<PSQTWeightType>(stream, psqtWeights, PSQTBuckets * InputDimensions);
214 return !stream.fail();
217 // Convert input features
218 std::int32_t transform(const Position& pos, OutputType* output, int bucket) const {
219 update_accumulator(pos, WHITE);
220 update_accumulator(pos, BLACK);
222 const Color perspectives[2] = {pos.side_to_move(), ~pos.side_to_move()};
223 const auto& accumulation = pos.state()->accumulator.accumulation;
224 const auto& psqtAccumulation = pos.state()->accumulator.psqtAccumulation;
227 psqtAccumulation[perspectives[0]][bucket]
228 - psqtAccumulation[perspectives[1]][bucket]
232 for (IndexType p = 0; p < 2; ++p)
234 const IndexType offset = (HalfDimensions / 2) * p;
236 #if defined(USE_AVX512)
238 constexpr IndexType OutputChunkSize = 512 / 8;
239 static_assert((HalfDimensions / 2) % OutputChunkSize == 0);
240 constexpr IndexType NumOutputChunks = HalfDimensions / 2 / OutputChunkSize;
242 const __m512i Zero = _mm512_setzero_si512();
243 const __m512i One = _mm512_set1_epi16(127);
244 const __m512i Control = _mm512_setr_epi64(0, 2, 4, 6, 1, 3, 5, 7);
246 const __m512i* in0 = reinterpret_cast<const __m512i*>(&(accumulation[perspectives[p]][0]));
247 const __m512i* in1 = reinterpret_cast<const __m512i*>(&(accumulation[perspectives[p]][HalfDimensions / 2]));
248 __m512i* out = reinterpret_cast< __m512i*>(output + offset);
250 for (IndexType j = 0; j < NumOutputChunks; j += 1)
252 const __m512i sum0a = _mm512_max_epi16(_mm512_min_epi16(in0[j * 2 + 0], One), Zero);
253 const __m512i sum0b = _mm512_max_epi16(_mm512_min_epi16(in0[j * 2 + 1], One), Zero);
254 const __m512i sum1a = _mm512_max_epi16(_mm512_min_epi16(in1[j * 2 + 0], One), Zero);
255 const __m512i sum1b = _mm512_max_epi16(_mm512_min_epi16(in1[j * 2 + 1], One), Zero);
257 const __m512i pa = _mm512_srli_epi16(_mm512_mullo_epi16(sum0a, sum1a), 7);
258 const __m512i pb = _mm512_srli_epi16(_mm512_mullo_epi16(sum0b, sum1b), 7);
260 out[j] = _mm512_permutexvar_epi64(Control, _mm512_packs_epi16(pa, pb));
263 #elif defined(USE_AVX2)
265 constexpr IndexType OutputChunkSize = 256 / 8;
266 static_assert((HalfDimensions / 2) % OutputChunkSize == 0);
267 constexpr IndexType NumOutputChunks = HalfDimensions / 2 / OutputChunkSize;
269 const __m256i Zero = _mm256_setzero_si256();
270 const __m256i One = _mm256_set1_epi16(127);
271 constexpr int Control = 0b11011000;
273 const __m256i* in0 = reinterpret_cast<const __m256i*>(&(accumulation[perspectives[p]][0]));
274 const __m256i* in1 = reinterpret_cast<const __m256i*>(&(accumulation[perspectives[p]][HalfDimensions / 2]));
275 __m256i* out = reinterpret_cast< __m256i*>(output + offset);
277 for (IndexType j = 0; j < NumOutputChunks; j += 1)
279 const __m256i sum0a = _mm256_max_epi16(_mm256_min_epi16(in0[j * 2 + 0], One), Zero);
280 const __m256i sum0b = _mm256_max_epi16(_mm256_min_epi16(in0[j * 2 + 1], One), Zero);
281 const __m256i sum1a = _mm256_max_epi16(_mm256_min_epi16(in1[j * 2 + 0], One), Zero);
282 const __m256i sum1b = _mm256_max_epi16(_mm256_min_epi16(in1[j * 2 + 1], One), Zero);
284 const __m256i pa = _mm256_srli_epi16(_mm256_mullo_epi16(sum0a, sum1a), 7);
285 const __m256i pb = _mm256_srli_epi16(_mm256_mullo_epi16(sum0b, sum1b), 7);
287 out[j] = _mm256_permute4x64_epi64(_mm256_packs_epi16(pa, pb), Control);
290 #elif defined(USE_SSE2)
292 constexpr IndexType OutputChunkSize = 128 / 8;
293 static_assert((HalfDimensions / 2) % OutputChunkSize == 0);
294 constexpr IndexType NumOutputChunks = HalfDimensions / 2 / OutputChunkSize;
296 const __m128i Zero = _mm_setzero_si128();
297 const __m128i One = _mm_set1_epi16(127);
299 const __m128i* in0 = reinterpret_cast<const __m128i*>(&(accumulation[perspectives[p]][0]));
300 const __m128i* in1 = reinterpret_cast<const __m128i*>(&(accumulation[perspectives[p]][HalfDimensions / 2]));
301 __m128i* out = reinterpret_cast< __m128i*>(output + offset);
303 for (IndexType j = 0; j < NumOutputChunks; j += 1)
305 const __m128i sum0a = _mm_max_epi16(_mm_min_epi16(in0[j * 2 + 0], One), Zero);
306 const __m128i sum0b = _mm_max_epi16(_mm_min_epi16(in0[j * 2 + 1], One), Zero);
307 const __m128i sum1a = _mm_max_epi16(_mm_min_epi16(in1[j * 2 + 0], One), Zero);
308 const __m128i sum1b = _mm_max_epi16(_mm_min_epi16(in1[j * 2 + 1], One), Zero);
310 const __m128i pa = _mm_srli_epi16(_mm_mullo_epi16(sum0a, sum1a), 7);
311 const __m128i pb = _mm_srli_epi16(_mm_mullo_epi16(sum0b, sum1b), 7);
313 out[j] = _mm_packs_epi16(pa, pb);
316 #elif defined(USE_NEON)
318 constexpr IndexType OutputChunkSize = 128 / 8;
319 static_assert((HalfDimensions / 2) % OutputChunkSize == 0);
320 constexpr IndexType NumOutputChunks = HalfDimensions / 2 / OutputChunkSize;
322 const int16x8_t Zero = vdupq_n_s16(0);
323 const int16x8_t One = vdupq_n_s16(127);
325 const int16x8_t* in0 = reinterpret_cast<const int16x8_t*>(&(accumulation[perspectives[p]][0]));
326 const int16x8_t* in1 = reinterpret_cast<const int16x8_t*>(&(accumulation[perspectives[p]][HalfDimensions / 2]));
327 int8x16_t* out = reinterpret_cast< int8x16_t*>(output + offset);
329 for (IndexType j = 0; j < NumOutputChunks; j += 1)
331 const int16x8_t sum0a = vmaxq_s16(vminq_s16(in0[j * 2 + 0], One), Zero);
332 const int16x8_t sum0b = vmaxq_s16(vminq_s16(in0[j * 2 + 1], One), Zero);
333 const int16x8_t sum1a = vmaxq_s16(vminq_s16(in1[j * 2 + 0], One), Zero);
334 const int16x8_t sum1b = vmaxq_s16(vminq_s16(in1[j * 2 + 1], One), Zero);
336 const int8x8_t pa = vshrn_n_s16(vmulq_s16(sum0a, sum1a), 7);
337 const int8x8_t pb = vshrn_n_s16(vmulq_s16(sum0b, sum1b), 7);
339 out[j] = vcombine_s8(pa, pb);
344 for (IndexType j = 0; j < HalfDimensions / 2; ++j) {
345 BiasType sum0 = accumulation[static_cast<int>(perspectives[p])][j + 0];
346 BiasType sum1 = accumulation[static_cast<int>(perspectives[p])][j + HalfDimensions / 2];
347 sum0 = std::max<int>(0, std::min<int>(127, sum0));
348 sum1 = std::max<int>(0, std::min<int>(127, sum1));
349 output[offset + j] = static_cast<OutputType>(sum0 * sum1 / 128);
357 } // end of function transform()
362 void update_accumulator(const Position& pos, const Color perspective) const {
364 // The size must be enough to contain the largest possible update.
365 // That might depend on the feature set and generally relies on the
366 // feature set's update cost calculation to be correct and never
367 // allow updates with more added/removed features than MaxActiveDimensions.
370 // Gcc-10.2 unnecessarily spills AVX2 registers if this array
371 // is defined in the VECTOR code below, once in each branch
373 psqt_vec_t psqt[NumPsqtRegs];
376 // Look for a usable accumulator of an earlier position. We keep track
377 // of the estimated gain in terms of features to be added/subtracted.
378 StateInfo *st = pos.state(), *next = nullptr;
379 int gain = FeatureSet::refresh_cost(pos);
380 while (st->previous && !st->accumulator.computed[perspective])
382 // This governs when a full feature refresh is needed and how many
383 // updates are better than just one full refresh.
384 if ( FeatureSet::requires_refresh(st, perspective)
385 || (gain -= FeatureSet::update_cost(st) + 1) < 0)
391 if (st->accumulator.computed[perspective])
396 // Update incrementally in two steps. First, we update the "next"
397 // accumulator. Then, we update the current accumulator (pos.state()).
399 // Gather all features to be updated.
400 const Square ksq = pos.square<KING>(perspective);
401 FeatureSet::IndexList removed[2], added[2];
402 FeatureSet::append_changed_indices(
403 ksq, next->dirtyPiece, perspective, removed[0], added[0]);
404 for (StateInfo *st2 = pos.state(); st2 != next; st2 = st2->previous)
405 FeatureSet::append_changed_indices(
406 ksq, st2->dirtyPiece, perspective, removed[1], added[1]);
408 // Mark the accumulators as computed.
409 next->accumulator.computed[perspective] = true;
410 pos.state()->accumulator.computed[perspective] = true;
412 // Now update the accumulators listed in states_to_update[], where the last element is a sentinel.
413 StateInfo *states_to_update[3] =
414 { next, next == pos.state() ? nullptr : pos.state(), nullptr };
416 for (IndexType j = 0; j < HalfDimensions / TileHeight; ++j)
419 auto accTile = reinterpret_cast<vec_t*>(
420 &st->accumulator.accumulation[perspective][j * TileHeight]);
421 for (IndexType k = 0; k < NumRegs; ++k)
422 acc[k] = vec_load(&accTile[k]);
424 for (IndexType i = 0; states_to_update[i]; ++i)
426 // Difference calculation for the deactivated features
427 for (const auto index : removed[i])
429 const IndexType offset = HalfDimensions * index + j * TileHeight;
430 auto column = reinterpret_cast<const vec_t*>(&weights[offset]);
431 for (IndexType k = 0; k < NumRegs; ++k)
432 acc[k] = vec_sub_16(acc[k], column[k]);
435 // Difference calculation for the activated features
436 for (const auto index : added[i])
438 const IndexType offset = HalfDimensions * index + j * TileHeight;
439 auto column = reinterpret_cast<const vec_t*>(&weights[offset]);
440 for (IndexType k = 0; k < NumRegs; ++k)
441 acc[k] = vec_add_16(acc[k], column[k]);
445 accTile = reinterpret_cast<vec_t*>(
446 &states_to_update[i]->accumulator.accumulation[perspective][j * TileHeight]);
447 for (IndexType k = 0; k < NumRegs; ++k)
448 vec_store(&accTile[k], acc[k]);
452 for (IndexType j = 0; j < PSQTBuckets / PsqtTileHeight; ++j)
455 auto accTilePsqt = reinterpret_cast<psqt_vec_t*>(
456 &st->accumulator.psqtAccumulation[perspective][j * PsqtTileHeight]);
457 for (std::size_t k = 0; k < NumPsqtRegs; ++k)
458 psqt[k] = vec_load_psqt(&accTilePsqt[k]);
460 for (IndexType i = 0; states_to_update[i]; ++i)
462 // Difference calculation for the deactivated features
463 for (const auto index : removed[i])
465 const IndexType offset = PSQTBuckets * index + j * PsqtTileHeight;
466 auto columnPsqt = reinterpret_cast<const psqt_vec_t*>(&psqtWeights[offset]);
467 for (std::size_t k = 0; k < NumPsqtRegs; ++k)
468 psqt[k] = vec_sub_psqt_32(psqt[k], columnPsqt[k]);
471 // Difference calculation for the activated features
472 for (const auto index : added[i])
474 const IndexType offset = PSQTBuckets * index + j * PsqtTileHeight;
475 auto columnPsqt = reinterpret_cast<const psqt_vec_t*>(&psqtWeights[offset]);
476 for (std::size_t k = 0; k < NumPsqtRegs; ++k)
477 psqt[k] = vec_add_psqt_32(psqt[k], columnPsqt[k]);
481 accTilePsqt = reinterpret_cast<psqt_vec_t*>(
482 &states_to_update[i]->accumulator.psqtAccumulation[perspective][j * PsqtTileHeight]);
483 for (std::size_t k = 0; k < NumPsqtRegs; ++k)
484 vec_store_psqt(&accTilePsqt[k], psqt[k]);
489 for (IndexType i = 0; states_to_update[i]; ++i)
491 std::memcpy(states_to_update[i]->accumulator.accumulation[perspective],
492 st->accumulator.accumulation[perspective],
493 HalfDimensions * sizeof(BiasType));
495 for (std::size_t k = 0; k < PSQTBuckets; ++k)
496 states_to_update[i]->accumulator.psqtAccumulation[perspective][k] = st->accumulator.psqtAccumulation[perspective][k];
498 st = states_to_update[i];
500 // Difference calculation for the deactivated features
501 for (const auto index : removed[i])
503 const IndexType offset = HalfDimensions * index;
505 for (IndexType j = 0; j < HalfDimensions; ++j)
506 st->accumulator.accumulation[perspective][j] -= weights[offset + j];
508 for (std::size_t k = 0; k < PSQTBuckets; ++k)
509 st->accumulator.psqtAccumulation[perspective][k] -= psqtWeights[index * PSQTBuckets + k];
512 // Difference calculation for the activated features
513 for (const auto index : added[i])
515 const IndexType offset = HalfDimensions * index;
517 for (IndexType j = 0; j < HalfDimensions; ++j)
518 st->accumulator.accumulation[perspective][j] += weights[offset + j];
520 for (std::size_t k = 0; k < PSQTBuckets; ++k)
521 st->accumulator.psqtAccumulation[perspective][k] += psqtWeights[index * PSQTBuckets + k];
528 // Refresh the accumulator
529 auto& accumulator = pos.state()->accumulator;
530 accumulator.computed[perspective] = true;
531 FeatureSet::IndexList active;
532 FeatureSet::append_active_indices(pos, perspective, active);
535 for (IndexType j = 0; j < HalfDimensions / TileHeight; ++j)
537 auto biasesTile = reinterpret_cast<const vec_t*>(
538 &biases[j * TileHeight]);
539 for (IndexType k = 0; k < NumRegs; ++k)
540 acc[k] = biasesTile[k];
542 for (const auto index : active)
544 const IndexType offset = HalfDimensions * index + j * TileHeight;
545 auto column = reinterpret_cast<const vec_t*>(&weights[offset]);
547 for (unsigned k = 0; k < NumRegs; ++k)
548 acc[k] = vec_add_16(acc[k], column[k]);
551 auto accTile = reinterpret_cast<vec_t*>(
552 &accumulator.accumulation[perspective][j * TileHeight]);
553 for (unsigned k = 0; k < NumRegs; k++)
554 vec_store(&accTile[k], acc[k]);
557 for (IndexType j = 0; j < PSQTBuckets / PsqtTileHeight; ++j)
559 for (std::size_t k = 0; k < NumPsqtRegs; ++k)
560 psqt[k] = vec_zero_psqt();
562 for (const auto index : active)
564 const IndexType offset = PSQTBuckets * index + j * PsqtTileHeight;
565 auto columnPsqt = reinterpret_cast<const psqt_vec_t*>(&psqtWeights[offset]);
567 for (std::size_t k = 0; k < NumPsqtRegs; ++k)
568 psqt[k] = vec_add_psqt_32(psqt[k], columnPsqt[k]);
571 auto accTilePsqt = reinterpret_cast<psqt_vec_t*>(
572 &accumulator.psqtAccumulation[perspective][j * PsqtTileHeight]);
573 for (std::size_t k = 0; k < NumPsqtRegs; ++k)
574 vec_store_psqt(&accTilePsqt[k], psqt[k]);
578 std::memcpy(accumulator.accumulation[perspective], biases,
579 HalfDimensions * sizeof(BiasType));
581 for (std::size_t k = 0; k < PSQTBuckets; ++k)
582 accumulator.psqtAccumulation[perspective][k] = 0;
584 for (const auto index : active)
586 const IndexType offset = HalfDimensions * index;
588 for (IndexType j = 0; j < HalfDimensions; ++j)
589 accumulator.accumulation[perspective][j] += weights[offset + j];
591 for (std::size_t k = 0; k < PSQTBuckets; ++k)
592 accumulator.psqtAccumulation[perspective][k] += psqtWeights[index * PSQTBuckets + k];
602 alignas(CacheLineSize) BiasType biases[HalfDimensions];
603 alignas(CacheLineSize) WeightType weights[HalfDimensions * InputDimensions];
604 alignas(CacheLineSize) PSQTWeightType psqtWeights[InputDimensions * PSQTBuckets];
607 } // namespace Stockfish::Eval::NNUE
609 #endif // #ifndef NNUE_FEATURE_TRANSFORMER_H_INCLUDED