Files
stockfish/src/nnue/nnue_accumulator.cpp
T
Wencey WangandJoost VandeVondele ffffe1bdb5 Add intrinsics for LSX and LASX
This adds actual intrinsics of SIMD on loongarch64, with considerable performance improvements.

Benchmark on `Loongson-3A6000-HV Not Specified CPU @ 2.5GHz`

Baseline GCC 14 (debian trixie):
```
===========================
Total time (ms) : 17816
Nodes searched  : 2336177
Nodes/second    : 131128
```

With this PR:

GCC 16 (debian sid):
```
./stockfish compiler
Stockfish dev-20260516-52e8d9ef by the Stockfish developers (see AUTHORS file)

Compiled by                : g++ (GNUC) 16.1.0 on Linux
Compilation architecture   : loongarch64-lasx
Compilation settings       : 64bit LASX LSX
Compiler __VERSION__ macro : 16.1.0
===========================
Total time (ms) : 3518
Nodes searched  : 2336177
Nodes/second    : 664063
```
```
./stockfish compiler
Stockfish dev-20260516-52e8d9ef by the Stockfish developers (see AUTHORS file)

Compiled by                : g++ (GNUC) 16.1.0 on Linux
Compilation architecture   : loongarch64-lsx
Compilation settings       : 64bit LSX
Compiler __VERSION__ macro : 16.1.0
===========================
Total time (ms) : 4944
Nodes searched  : 2336177
Nodes/second    : 472527
```

clang 22 (debian sid):
```
./stockfish compiler
Stockfish dev-20260516-52e8d9ef by the Stockfish developers (see AUTHORS file)

Compiled by                : clang++ 22.1.5 on Linux
Compilation architecture   : loongarch64-lasx
Compilation settings       : 64bit LASX LSX
Compiler __VERSION__ macro : Debian Clang 22.1.5 (1)
===========================
Total time (ms) : 3401
Nodes searched  : 2336177
Nodes/second    : 686908
```
```
./stockfish compiler
Stockfish dev-20260516-52e8d9ef by the Stockfish developers (see AUTHORS file)

Compiled by                : clang++ 22.1.5 on Linux
Compilation architecture   : loongarch64-lsx
Compilation settings       : 64bit LSX
Compiler __VERSION__ macro : Debian Clang 22.1.5 (1)
===========================
Total time (ms) : 5501
Nodes searched  : 2336177
Nodes/second    : 424682
```

GCC 14 (debian trixie):
```
./stockfish compiler
Stockfish dev-20260516-52e8d9ef by the Stockfish developers (see AUTHORS file)

Compiled by                : g++ (GNUC) 14.2.0 on Linux
Compilation architecture   : loongarch64-lasx
Compilation settings       : 64bit LASX LSX
Compiler __VERSION__ macro : 14.2.0
===========================
Total time (ms) : 3559
Nodes searched  : 2336177
Nodes/second    : 656413
```
```
./stockfish compiler
Stockfish dev-20260516-52e8d9ef by the Stockfish developers (see AUTHORS file)

Compiled by                : g++ (GNUC) 14.2.0 on Linux
Compilation architecture   : loongarch64-lsx
Compilation settings       : 64bit LSX
Compiler __VERSION__ macro : 14.2.0
===========================
Total time (ms) : 5212
Nodes searched  : 2336177
Nodes/second    : 448230
```

clang 19 (debian trixie):
```
./stockfish compiler
Stockfish dev-20260516-52e8d9ef by the Stockfish developers (see AUTHORS file)

Compiled by                : clang++ 19.1.7 on Linux
Compilation architecture   : loongarch64-lasx
Compilation settings       : 64bit LASX LSX
Compiler __VERSION__ macro : Debian Clang 19.1.7 (3+b1)
===========================
Total time (ms) : 4830
Nodes searched  : 2336177
Nodes/second    : 483680
```
```
./stockfish compiler
Stockfish dev-20260516-52e8d9ef by the Stockfish developers (see AUTHORS file)

Compiled by                : clang++ 19.1.7 on Linux
Compilation architecture   : loongarch64-lsx
Compilation settings       : 64bit LSX
Compiler __VERSION__ macro : Debian Clang 19.1.7 (3+b1)
===========================
Total time (ms) : 5568
Nodes searched  : 2336177
Nodes/second    : 419572
```

closes https://github.com/official-stockfish/Stockfish/pull/6815

No functional change
2026-05-17 20:42:36 +02:00

823 lines
32 KiB
C++

/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2026 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/>.
*/
#include "nnue_accumulator.h"
#include <cassert>
#include <cstdint>
#include <new>
#include <type_traits>
#include "../bitboard.h"
#include "../misc.h"
#include "../position.h"
#include "../types.h"
#include "nnue_architecture.h"
#include "nnue_common.h"
#include "nnue_feature_transformer.h" // IWYU pragma: keep
#include "simd.h"
namespace Stockfish::Eval::NNUE {
using namespace SIMD;
namespace {
template<bool Forward, typename FeatureSet>
void update_accumulator_incremental(Color perspective,
const FeatureTransformer& featureTransformer,
const Square ksq,
AccumulatorState<FeatureSet>& target_state,
const AccumulatorState<FeatureSet>& computed);
void update_accumulator_refresh_cache(Color perspective,
const FeatureTransformer& featureTransformer,
const Position& pos,
AccumulatorState<PSQFeatureSet>& accumulatorState,
AccumulatorCaches& cache);
void update_threats_accumulator_full(Color perspective,
const FeatureTransformer& featureTransformer,
const Position& pos,
AccumulatorState<ThreatFeatureSet>& accumulatorState);
}
template<typename T>
const AccumulatorState<T>& AccumulatorStack::latest() const noexcept {
return accumulators<T>()[size - 1];
}
// Explicit template instantiations
template const AccumulatorState<PSQFeatureSet>& AccumulatorStack::latest() const noexcept;
template const AccumulatorState<ThreatFeatureSet>& AccumulatorStack::latest() const noexcept;
template<typename T>
AccumulatorState<T>& AccumulatorStack::mut_latest() noexcept {
return mut_accumulators<T>()[size - 1];
}
template<typename T>
const std::array<AccumulatorState<T>, AccumulatorStack::MaxSize>&
AccumulatorStack::accumulators() const noexcept {
static_assert(std::is_same_v<T, PSQFeatureSet> || std::is_same_v<T, ThreatFeatureSet>,
"Invalid Feature Set Type");
if constexpr (std::is_same_v<T, PSQFeatureSet>)
return psq_accumulators;
if constexpr (std::is_same_v<T, ThreatFeatureSet>)
return threat_accumulators;
}
template<typename T>
std::array<AccumulatorState<T>, AccumulatorStack::MaxSize>&
AccumulatorStack::mut_accumulators() noexcept {
static_assert(std::is_same_v<T, PSQFeatureSet> || std::is_same_v<T, ThreatFeatureSet>,
"Invalid Feature Set Type");
if constexpr (std::is_same_v<T, PSQFeatureSet>)
return psq_accumulators;
if constexpr (std::is_same_v<T, ThreatFeatureSet>)
return threat_accumulators;
}
void AccumulatorStack::reset() noexcept {
psq_accumulators[0].reset({});
threat_accumulators[0].reset({});
size = 1;
}
std::pair<DirtyPiece&, DirtyThreats&> AccumulatorStack::push() noexcept {
assert(size < MaxSize);
auto& dp = psq_accumulators[size].reset();
auto& dts = threat_accumulators[size].reset();
new (&dts) DirtyThreats;
size++;
return {dp, dts};
}
void AccumulatorStack::pop() noexcept {
assert(size > 1);
size--;
}
void AccumulatorStack::evaluate(const Position& pos,
const FeatureTransformer& featureTransformer,
// Silence spurious warning on GCC 10
[[maybe_unused]] AccumulatorCaches& cache) noexcept {
evaluate_side<PSQFeatureSet>(WHITE, pos, featureTransformer, cache);
evaluate_side<PSQFeatureSet>(BLACK, pos, featureTransformer, cache);
evaluate_side<ThreatFeatureSet>(WHITE, pos, featureTransformer, cache);
evaluate_side<ThreatFeatureSet>(BLACK, pos, featureTransformer, cache);
}
template<typename FeatureSet>
void AccumulatorStack::evaluate_side(Color perspective,
const Position& pos,
const FeatureTransformer& featureTransformer,
AccumulatorCaches& cache) noexcept {
const auto last_usable_accum = find_last_usable_accumulator<FeatureSet>(perspective);
if (accumulators<FeatureSet>()[last_usable_accum].computed[perspective])
forward_update_incremental<FeatureSet>(perspective, pos, featureTransformer,
last_usable_accum);
else
{
if constexpr (std::is_same_v<FeatureSet, PSQFeatureSet>)
update_accumulator_refresh_cache(perspective, featureTransformer, pos,
mut_latest<PSQFeatureSet>(), cache);
else
update_threats_accumulator_full(perspective, featureTransformer, pos,
mut_latest<ThreatFeatureSet>());
backward_update_incremental<FeatureSet>(perspective, pos, featureTransformer,
last_usable_accum);
}
}
// Find the earliest usable accumulator, this can either be a computed accumulator or the accumulator
// state just before a change that requires full refresh.
template<typename FeatureSet>
std::size_t AccumulatorStack::find_last_usable_accumulator(Color perspective) const noexcept {
for (std::size_t curr_idx = size - 1; curr_idx > 0; curr_idx--)
{
if (accumulators<FeatureSet>()[curr_idx].computed[perspective])
return curr_idx;
if (FeatureSet::requires_refresh(accumulators<FeatureSet>()[curr_idx].diff, perspective))
return curr_idx;
}
return 0;
}
template<typename FeatureSet>
void AccumulatorStack::forward_update_incremental(Color perspective,
const Position& pos,
const FeatureTransformer& featureTransformer,
const std::size_t begin) noexcept {
assert(begin < accumulators<FeatureSet>().size());
assert(accumulators<FeatureSet>()[begin].computed[perspective]);
const Square ksq = pos.square<KING>(perspective);
for (std::size_t next = begin + 1; next < size; next++)
{
update_accumulator_incremental<true>(perspective, featureTransformer, ksq,
mut_accumulators<FeatureSet>()[next],
accumulators<FeatureSet>()[next - 1]);
}
assert(latest<FeatureSet>().computed[perspective]);
}
template<typename FeatureSet>
void AccumulatorStack::backward_update_incremental(Color perspective,
const Position& pos,
const FeatureTransformer& featureTransformer,
const std::size_t end) noexcept {
assert(end < accumulators<FeatureSet>().size());
assert(end < size);
assert(latest<FeatureSet>().computed[perspective]);
const Square ksq = pos.square<KING>(perspective);
for (std::int64_t next = std::int64_t(size) - 2; next >= std::int64_t(end); next--)
update_accumulator_incremental<false>(perspective, featureTransformer, ksq,
mut_accumulators<FeatureSet>()[next],
accumulators<FeatureSet>()[next + 1]);
assert(accumulators<FeatureSet>()[end].computed[perspective]);
}
namespace {
template<typename VectorWrapper,
IndexType Width,
UpdateOperation... ops,
typename ElementType,
typename... Ts,
std::enable_if_t<is_all_same_v<ElementType, Ts...>, bool> = true>
void fused_row_reduce(const ElementType* in, ElementType* out, const Ts* const... rows) {
constexpr IndexType size = Width * sizeof(ElementType) / sizeof(typename VectorWrapper::type);
auto* vecIn = reinterpret_cast<const typename VectorWrapper::type*>(in);
auto* vecOut = reinterpret_cast<typename VectorWrapper::type*>(out);
for (IndexType i = 0; i < size; ++i)
vecOut[i] = fused<VectorWrapper, ops...>(
vecIn[i], reinterpret_cast<const typename VectorWrapper::type*>(rows)[i]...);
}
template<typename FeatureSet>
struct AccumulatorUpdateContext {
Color perspective;
const FeatureTransformer& featureTransformer;
const AccumulatorState<FeatureSet>& from;
AccumulatorState<FeatureSet>& to;
AccumulatorUpdateContext(Color persp,
const FeatureTransformer& ft,
const AccumulatorState<FeatureSet>& accF,
AccumulatorState<FeatureSet>& accT) noexcept :
perspective{persp},
featureTransformer{ft},
from{accF},
to{accT} {}
template<UpdateOperation... ops,
typename... Ts,
std::enable_if_t<is_all_same_v<IndexType, Ts...>, bool> = true>
void apply(const Ts... indices) {
constexpr IndexType Dimensions = FeatureTransformer::OutputDimensions;
auto to_weight_vector = [&](const IndexType index) {
return &featureTransformer.weights[index * Dimensions];
};
auto to_psqt_weight_vector = [&](const IndexType index) {
return &featureTransformer.psqtWeights[index * PSQTBuckets];
};
fused_row_reduce<Vec16Wrapper, Dimensions, ops...>(from.accumulation[perspective].data(),
to.accumulation[perspective].data(),
to_weight_vector(indices)...);
fused_row_reduce<Vec32Wrapper, PSQTBuckets, ops...>(
from.psqtAccumulation[perspective].data(), to.psqtAccumulation[perspective].data(),
to_psqt_weight_vector(indices)...);
}
void apply(const typename FeatureSet::IndexList& added,
const typename FeatureSet::IndexList& removed) {
constexpr IndexType Dimensions = FeatureTransformer::OutputDimensions;
const auto& fromAcc = from.accumulation[perspective];
auto& toAcc = to.accumulation[perspective];
const auto& fromPsqtAcc = from.psqtAccumulation[perspective];
auto& toPsqtAcc = to.psqtAccumulation[perspective];
#ifdef VECTOR
using Tiling = SIMDTiling<Dimensions, Dimensions, PSQTBuckets>;
vec_t acc[Tiling::NumRegs];
psqt_vec_t psqt[Tiling::NumPsqtRegs];
const auto* threatWeights = &featureTransformer.threatWeights[0];
for (IndexType j = 0; j < Dimensions / Tiling::TileHeight; ++j)
{
auto* fromTile = reinterpret_cast<const vec_t*>(&fromAcc[j * Tiling::TileHeight]);
auto* toTile = reinterpret_cast<vec_t*>(&toAcc[j * Tiling::TileHeight]);
for (IndexType k = 0; k < Tiling::NumRegs; ++k)
acc[k] = fromTile[k];
for (int i = 0; i < removed.ssize(); ++i)
{
size_t index = removed[i];
const size_t offset = Dimensions * index;
auto* column = reinterpret_cast<const vec_i8_t*>(&threatWeights[offset]);
#ifdef USE_NEON
for (IndexType k = 0; k < Tiling::NumRegs; k += 2)
{
acc[k] = vsubw_s8(acc[k], vget_low_s8(column[k / 2]));
acc[k + 1] = vsubw_high_s8(acc[k + 1], column[k / 2]);
}
#else
for (IndexType k = 0; k < Tiling::NumRegs; ++k)
acc[k] = vec_sub_16(acc[k], vec_convert_8_16(column[k]));
#endif
}
for (int i = 0; i < added.ssize(); ++i)
{
size_t index = added[i];
const size_t offset = Dimensions * index;
auto* column = reinterpret_cast<const vec_i8_t*>(&threatWeights[offset]);
#ifdef USE_NEON
for (IndexType k = 0; k < Tiling::NumRegs; k += 2)
{
acc[k] = vaddw_s8(acc[k], vget_low_s8(column[k / 2]));
acc[k + 1] = vaddw_high_s8(acc[k + 1], column[k / 2]);
}
#else
for (IndexType k = 0; k < Tiling::NumRegs; ++k)
acc[k] = vec_add_16(acc[k], vec_convert_8_16(column[k]));
#endif
}
for (IndexType k = 0; k < Tiling::NumRegs; k++)
vec_store(&toTile[k], acc[k]);
threatWeights += Tiling::TileHeight;
}
for (IndexType j = 0; j < PSQTBuckets / Tiling::PsqtTileHeight; ++j)
{
auto* fromTilePsqt =
reinterpret_cast<const psqt_vec_t*>(&fromPsqtAcc[j * Tiling::PsqtTileHeight]);
auto* toTilePsqt =
reinterpret_cast<psqt_vec_t*>(&toPsqtAcc[j * Tiling::PsqtTileHeight]);
for (IndexType k = 0; k < Tiling::NumPsqtRegs; ++k)
psqt[k] = fromTilePsqt[k];
for (int i = 0; i < removed.ssize(); ++i)
{
size_t index = removed[i];
const size_t offset = PSQTBuckets * index + j * Tiling::PsqtTileHeight;
auto* columnPsqt = reinterpret_cast<const psqt_vec_t*>(
&featureTransformer.threatPsqtWeights[offset]);
for (std::size_t k = 0; k < Tiling::NumPsqtRegs; ++k)
psqt[k] = vec_sub_psqt_32(psqt[k], columnPsqt[k]);
}
for (int i = 0; i < added.ssize(); ++i)
{
size_t index = added[i];
const size_t offset = PSQTBuckets * index + j * Tiling::PsqtTileHeight;
auto* columnPsqt = reinterpret_cast<const psqt_vec_t*>(
&featureTransformer.threatPsqtWeights[offset]);
for (std::size_t k = 0; k < Tiling::NumPsqtRegs; ++k)
psqt[k] = vec_add_psqt_32(psqt[k], columnPsqt[k]);
}
for (IndexType k = 0; k < Tiling::NumPsqtRegs; ++k)
vec_store_psqt(&toTilePsqt[k], psqt[k]);
}
#else
toAcc = fromAcc;
toPsqtAcc = fromPsqtAcc;
for (const auto index : removed)
{
const IndexType offset = Dimensions * index;
for (IndexType j = 0; j < Dimensions; ++j)
toAcc[j] -= featureTransformer.threatWeights[offset + j];
for (std::size_t k = 0; k < PSQTBuckets; ++k)
toPsqtAcc[k] -= featureTransformer.threatPsqtWeights[index * PSQTBuckets + k];
}
for (const auto index : added)
{
const IndexType offset = Dimensions * index;
for (IndexType j = 0; j < Dimensions; ++j)
toAcc[j] += featureTransformer.threatWeights[offset + j];
for (std::size_t k = 0; k < PSQTBuckets; ++k)
toPsqtAcc[k] += featureTransformer.threatPsqtWeights[index * PSQTBuckets + k];
}
#endif
}
};
template<typename FeatureSet>
auto make_accumulator_update_context(Color perspective,
const FeatureTransformer& featureTransformer,
const AccumulatorState<FeatureSet>& accumulatorFrom,
AccumulatorState<FeatureSet>& accumulatorTo) noexcept {
return AccumulatorUpdateContext<FeatureSet>{perspective, featureTransformer, accumulatorFrom,
accumulatorTo};
}
template<bool Forward, typename FeatureSet>
void update_accumulator_incremental(Color perspective,
const FeatureTransformer& featureTransformer,
const Square ksq,
AccumulatorState<FeatureSet>& target_state,
const AccumulatorState<FeatureSet>& computed) {
assert(computed.computed[perspective]);
assert(!target_state.computed[perspective]);
// The size must be enough to contain the largest possible update.
// That might depend on the feature set and generally relies on the
// feature set's update cost calculation to be correct and never allow
// updates with more added/removed features than MaxActiveDimensions.
// In this case, the maximum size of both feature addition and removal
// is 2, since we are incrementally updating one move at a time.
typename FeatureSet::IndexList removed, added;
if constexpr (std::is_same_v<FeatureSet, ThreatFeatureSet>)
{
const auto* pfBase = &featureTransformer.threatWeights[0];
IndexType pfStride = FeatureTransformer::OutputDimensions;
if constexpr (Forward)
FeatureSet::append_changed_indices(perspective, ksq, target_state.diff, removed, added,
nullptr, false, pfBase, pfStride);
else
FeatureSet::append_changed_indices(perspective, ksq, computed.diff, added, removed,
nullptr, false, pfBase, pfStride);
}
else
{
if constexpr (Forward)
FeatureSet::append_changed_indices(perspective, ksq, target_state.diff, removed, added);
else
FeatureSet::append_changed_indices(perspective, ksq, computed.diff, added, removed);
}
auto updateContext =
make_accumulator_update_context(perspective, featureTransformer, computed, target_state);
if constexpr (std::is_same_v<FeatureSet, ThreatFeatureSet>)
updateContext.apply(added, removed);
else
{
[[maybe_unused]] const int addedSize = added.ssize();
[[maybe_unused]] const int removedSize = removed.ssize();
assert(addedSize == 1 || addedSize == 2);
assert(removedSize == 1 || removedSize == 2);
assert((Forward && addedSize <= removedSize) || (!Forward && addedSize >= removedSize));
// Workaround compiler warning for uninitialized variables, replicated
// on profile builds on windows with gcc 14.2.0.
// Also helps with optimizations on some compilers.
sf_assume(addedSize == 1 || addedSize == 2);
sf_assume(removedSize == 1 || removedSize == 2);
if (!(removedSize == 1 || removedSize == 2) || !(addedSize == 1 || addedSize == 2))
sf_unreachable();
if ((Forward && removedSize == 1) || (!Forward && addedSize == 1))
{
assert(addedSize == 1 && removedSize == 1);
updateContext.template apply<Add, Sub>(added[0], removed[0]);
}
else if (Forward && addedSize == 1)
{
assert(removedSize == 2);
updateContext.template apply<Add, Sub, Sub>(added[0], removed[0], removed[1]);
}
else if (!Forward && removedSize == 1)
{
assert(addedSize == 2);
updateContext.template apply<Add, Add, Sub>(added[0], added[1], removed[0]);
}
else
{
assert(addedSize == 2 && removedSize == 2);
updateContext.template apply<Add, Add, Sub, Sub>(added[0], added[1], removed[0],
removed[1]);
}
}
target_state.computed[perspective] = true;
}
Bitboard get_changed_pieces(const std::array<Piece, SQUARE_NB>& oldPieces,
const std::array<Piece, SQUARE_NB>& newPieces) {
#if defined(USE_AVX2)
static_assert(sizeof(Piece) == 1);
Bitboard sameBB = 0;
for (int i = 0; i < 64; i += 32)
{
const __m256i old_v = _mm256_loadu_si256(reinterpret_cast<const __m256i*>(&oldPieces[i]));
const __m256i new_v = _mm256_loadu_si256(reinterpret_cast<const __m256i*>(&newPieces[i]));
const __m256i cmpEqual = _mm256_cmpeq_epi8(old_v, new_v);
const std::uint32_t equalMask = _mm256_movemask_epi8(cmpEqual);
sameBB |= static_cast<Bitboard>(equalMask) << i;
}
return ~sameBB;
#elif defined(USE_LASX)
static_assert(sizeof(Piece) == 1);
Bitboard changed = 0;
for (int i = 0; i < 64; i += 32)
{
const __m256i old_v = __lasx_xvld(reinterpret_cast<const void*>(&oldPieces[i]), 0);
const __m256i new_v = __lasx_xvld(reinterpret_cast<const void*>(&newPieces[i]), 0);
const __m256i diff = __lasx_xvxor_v(old_v, new_v);
const __m256i mask = __lasx_xvmsknz_b(diff);
const auto lo = static_cast<std::uint16_t>(__lasx_xvpickve2gr_d(mask, 0));
const auto hi = static_cast<std::uint16_t>(__lasx_xvpickve2gr_d(mask, 2));
changed |= (static_cast<Bitboard>(lo) | (static_cast<Bitboard>(hi) << 16)) << i;
}
return changed;
#elif defined(USE_LSX)
static_assert(sizeof(Piece) == 1);
Bitboard changed = 0;
for (int i = 0; i < 64; i += 16)
{
const __m128i old_v = __lsx_vld(reinterpret_cast<const void*>(&oldPieces[i]), 0);
const __m128i new_v = __lsx_vld(reinterpret_cast<const void*>(&newPieces[i]), 0);
const __m128i diff = __lsx_vxor_v(old_v, new_v);
const __m128i mask = __lsx_vmsknz_b(diff);
changed |= static_cast<Bitboard>(static_cast<std::uint16_t>(__lsx_vpickve2gr_d(mask, 0)))
<< i;
}
return changed;
#elif defined(USE_NEON)
uint8x16x4_t old_v = vld4q_u8(reinterpret_cast<const uint8_t*>(oldPieces.data()));
uint8x16x4_t new_v = vld4q_u8(reinterpret_cast<const uint8_t*>(newPieces.data()));
auto cmp = [=](const int i) { return vceqq_u8(old_v.val[i], new_v.val[i]); };
uint8x16_t cmp0_1 = vsriq_n_u8(cmp(1), cmp(0), 1);
uint8x16_t cmp2_3 = vsriq_n_u8(cmp(3), cmp(2), 1);
uint8x16_t merged = vsriq_n_u8(cmp2_3, cmp0_1, 2);
merged = vsriq_n_u8(merged, merged, 4);
uint8x8_t sameBB = vshrn_n_u16(vreinterpretq_u16_u8(merged), 4);
return ~vget_lane_u64(vreinterpret_u64_u8(sameBB), 0);
#else
Bitboard changed = 0;
for (Square sq = SQUARE_ZERO; sq < SQUARE_NB; ++sq)
changed |= static_cast<Bitboard>(oldPieces[sq] != newPieces[sq]) << sq;
return changed;
#endif
}
void update_accumulator_refresh_cache(Color perspective,
const FeatureTransformer& featureTransformer,
const Position& pos,
AccumulatorState<PSQFeatureSet>& accumulator,
AccumulatorCaches& cache) {
constexpr auto Dimensions = FeatureTransformer::OutputDimensions;
using Tiling [[maybe_unused]] = SIMDTiling<Dimensions, Dimensions, PSQTBuckets>;
const Square ksq = pos.square<KING>(perspective);
auto& entry = cache[ksq][perspective];
PSQFeatureSet::IndexList removed, added;
const Bitboard changedBB = get_changed_pieces(entry.pieces, pos.piece_array());
Bitboard removedBB = changedBB & entry.pieceBB;
Bitboard addedBB = changedBB & pos.pieces();
#if defined(USE_AVX512ICL)
PSQFeatureSet::write_indices(entry.pieces, pos.piece_array(), removedBB, addedBB, perspective,
ksq, removed, added);
#else
while (removedBB)
{
Square sq = pop_lsb(removedBB);
removed.push_back(PSQFeatureSet::make_index(perspective, sq, entry.pieces[sq], ksq));
}
while (addedBB)
{
Square sq = pop_lsb(addedBB);
added.push_back(PSQFeatureSet::make_index(perspective, sq, pos.piece_on(sq), ksq));
}
#endif
entry.pieceBB = pos.pieces();
entry.pieces = pos.piece_array();
accumulator.computed[perspective] = true;
#ifdef VECTOR
vec_t acc[Tiling::NumRegs];
psqt_vec_t psqt[Tiling::NumPsqtRegs];
const auto* weights = &featureTransformer.weights[0];
for (IndexType j = 0; j < Dimensions / Tiling::TileHeight; ++j)
{
auto* accTile =
reinterpret_cast<vec_t*>(&accumulator.accumulation[perspective][j * Tiling::TileHeight]);
auto* entryTile = reinterpret_cast<vec_t*>(&entry.accumulation[j * Tiling::TileHeight]);
for (IndexType k = 0; k < Tiling::NumRegs; ++k)
acc[k] = entryTile[k];
for (int i = 0; i < removed.ssize(); ++i)
{
size_t index = removed[i];
const size_t offset = Dimensions * index;
auto* column = reinterpret_cast<const vec_t*>(&weights[offset]);
for (IndexType k = 0; k < Tiling::NumRegs; ++k)
acc[k] = vec_sub_16(acc[k], column[k]);
}
for (int i = 0; i < added.ssize(); ++i)
{
size_t index = added[i];
const size_t offset = Dimensions * index;
auto* column = reinterpret_cast<const vec_t*>(&weights[offset]);
for (IndexType k = 0; k < Tiling::NumRegs; ++k)
acc[k] = vec_add_16(acc[k], column[k]);
}
for (IndexType k = 0; k < Tiling::NumRegs; k++)
vec_store(&entryTile[k], acc[k]);
for (IndexType k = 0; k < Tiling::NumRegs; k++)
vec_store(&accTile[k], acc[k]);
weights += Tiling::TileHeight;
}
for (IndexType j = 0; j < PSQTBuckets / Tiling::PsqtTileHeight; ++j)
{
auto* accTilePsqt = reinterpret_cast<psqt_vec_t*>(
&accumulator.psqtAccumulation[perspective][j * Tiling::PsqtTileHeight]);
auto* entryTilePsqt =
reinterpret_cast<psqt_vec_t*>(&entry.psqtAccumulation[j * Tiling::PsqtTileHeight]);
for (IndexType k = 0; k < Tiling::NumPsqtRegs; ++k)
psqt[k] = entryTilePsqt[k];
for (int i = 0; i < removed.ssize(); ++i)
{
size_t index = removed[i];
const size_t offset = PSQTBuckets * index + j * Tiling::PsqtTileHeight;
auto* columnPsqt =
reinterpret_cast<const psqt_vec_t*>(&featureTransformer.psqtWeights[offset]);
for (std::size_t k = 0; k < Tiling::NumPsqtRegs; ++k)
psqt[k] = vec_sub_psqt_32(psqt[k], columnPsqt[k]);
}
for (int i = 0; i < added.ssize(); ++i)
{
size_t index = added[i];
const size_t offset = PSQTBuckets * index + j * Tiling::PsqtTileHeight;
auto* columnPsqt =
reinterpret_cast<const psqt_vec_t*>(&featureTransformer.psqtWeights[offset]);
for (std::size_t k = 0; k < Tiling::NumPsqtRegs; ++k)
psqt[k] = vec_add_psqt_32(psqt[k], columnPsqt[k]);
}
for (IndexType k = 0; k < Tiling::NumPsqtRegs; ++k)
vec_store_psqt(&entryTilePsqt[k], psqt[k]);
for (IndexType k = 0; k < Tiling::NumPsqtRegs; ++k)
vec_store_psqt(&accTilePsqt[k], psqt[k]);
}
#else
for (const auto index : removed)
{
const IndexType offset = Dimensions * index;
for (IndexType j = 0; j < Dimensions; ++j)
entry.accumulation[j] -= featureTransformer.weights[offset + j];
for (std::size_t k = 0; k < PSQTBuckets; ++k)
entry.psqtAccumulation[k] -= featureTransformer.psqtWeights[index * PSQTBuckets + k];
}
for (const auto index : added)
{
const IndexType offset = Dimensions * index;
for (IndexType j = 0; j < Dimensions; ++j)
entry.accumulation[j] += featureTransformer.weights[offset + j];
for (std::size_t k = 0; k < PSQTBuckets; ++k)
entry.psqtAccumulation[k] += featureTransformer.psqtWeights[index * PSQTBuckets + k];
}
// The accumulator of the refresh entry has been updated.
// Now copy its content to the actual accumulator we were refreshing.
accumulator.accumulation[perspective] = entry.accumulation;
accumulator.psqtAccumulation[perspective] = entry.psqtAccumulation;
#endif
}
void update_threats_accumulator_full(Color perspective,
const FeatureTransformer& featureTransformer,
const Position& pos,
AccumulatorState<ThreatFeatureSet>& accumulator) {
constexpr IndexType Dimensions = FeatureTransformer::OutputDimensions;
using Tiling [[maybe_unused]] = SIMDTiling<Dimensions, Dimensions, PSQTBuckets>;
ThreatFeatureSet::IndexList active;
ThreatFeatureSet::append_active_indices(perspective, pos, active);
accumulator.computed[perspective] = true;
#ifdef VECTOR
vec_t acc[Tiling::NumRegs];
psqt_vec_t psqt[Tiling::NumPsqtRegs];
const auto* threatWeights = &featureTransformer.threatWeights[0];
for (IndexType j = 0; j < Dimensions / Tiling::TileHeight; ++j)
{
auto* accTile =
reinterpret_cast<vec_t*>(&accumulator.accumulation[perspective][j * Tiling::TileHeight]);
for (IndexType k = 0; k < Tiling::NumRegs; ++k)
acc[k] = vec_zero();
int i = 0;
for (; i < active.ssize(); ++i)
{
size_t index = active[i];
const size_t offset = Dimensions * index;
auto* column = reinterpret_cast<const vec_i8_t*>(&threatWeights[offset]);
#ifdef USE_NEON
for (IndexType k = 0; k < Tiling::NumRegs; k += 2)
{
acc[k] = vaddw_s8(acc[k], vget_low_s8(column[k / 2]));
acc[k + 1] = vaddw_high_s8(acc[k + 1], column[k / 2]);
}
#else
for (IndexType k = 0; k < Tiling::NumRegs; ++k)
acc[k] = vec_add_16(acc[k], vec_convert_8_16(column[k]));
#endif
}
for (IndexType k = 0; k < Tiling::NumRegs; k++)
vec_store(&accTile[k], acc[k]);
threatWeights += Tiling::TileHeight;
}
for (IndexType j = 0; j < PSQTBuckets / Tiling::PsqtTileHeight; ++j)
{
auto* accTilePsqt = reinterpret_cast<psqt_vec_t*>(
&accumulator.psqtAccumulation[perspective][j * Tiling::PsqtTileHeight]);
for (IndexType k = 0; k < Tiling::NumPsqtRegs; ++k)
psqt[k] = vec_zero_psqt();
for (int i = 0; i < active.ssize(); ++i)
{
size_t index = active[i];
const size_t offset = PSQTBuckets * index + j * Tiling::PsqtTileHeight;
auto* columnPsqt =
reinterpret_cast<const psqt_vec_t*>(&featureTransformer.threatPsqtWeights[offset]);
for (std::size_t k = 0; k < Tiling::NumPsqtRegs; ++k)
psqt[k] = vec_add_psqt_32(psqt[k], columnPsqt[k]);
}
for (IndexType k = 0; k < Tiling::NumPsqtRegs; ++k)
vec_store_psqt(&accTilePsqt[k], psqt[k]);
}
#else
for (IndexType j = 0; j < Dimensions; ++j)
accumulator.accumulation[perspective][j] = 0;
for (std::size_t k = 0; k < PSQTBuckets; ++k)
accumulator.psqtAccumulation[perspective][k] = 0;
for (const auto index : active)
{
const IndexType offset = Dimensions * index;
for (IndexType j = 0; j < Dimensions; ++j)
accumulator.accumulation[perspective][j] +=
featureTransformer.threatWeights[offset + j];
for (std::size_t k = 0; k < PSQTBuckets; ++k)
accumulator.psqtAccumulation[perspective][k] +=
featureTransformer.threatPsqtWeights[index * PSQTBuckets + k];
}
#endif
}
}
}