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#pragma once
#include "lrc.h"
#include "helpers.h"
#include "isa_erasure.h"
extern "C" {
#include <contrib/libs/isa-l/include/erasure_code.h>
}
#include <library/cpp/sse/sse.h>
#include <util/generic/array_ref.h>
#include <optional>
#include <vector>
namespace NErasure {
template <int DataPartCount, int ParityPartCount, int WordSize, class TCodecTraits>
class TLrcIsa
: public TLrcCodecBase<DataPartCount, ParityPartCount, WordSize, TCodecTraits>
{
static_assert(WordSize == 8, "ISA-l erasure codes support computations only in GF(2^8)");
public:
//! Main blob for storing data.
using TBlobType = typename TCodecTraits::TBlobType;
//! Main mutable blob for decoding data.
using TMutableBlobType = typename TCodecTraits::TMutableBlobType;
static constexpr ui64 RequiredDataAlignment = alignof(ui64);
TLrcIsa()
: TLrcCodecBase<DataPartCount, ParityPartCount, WordSize, TCodecTraits>()
{
EncodeGFTables_.resize(DataPartCount * ParityPartCount * 32, 0);
GeneratorMatrix_.resize((DataPartCount + ParityPartCount) * DataPartCount, 0);
for (int row = 0; row < DataPartCount; ++row) {
GeneratorMatrix_[row * DataPartCount + row] = 1;
}
this->template InitializeGeneratorMatrix<typename decltype(GeneratorMatrix_)::value_type>(
&GeneratorMatrix_[DataPartCount * DataPartCount],
std::bind(&gf_mul_erasure, std::placeholders::_1, std::placeholders::_1));
ec_init_tables(
DataPartCount,
ParityPartCount,
&GeneratorMatrix_.data()[DataPartCount * DataPartCount],
EncodeGFTables_.data());
}
std::vector<TBlobType> Encode(const std::vector<TBlobType>& blocks) const override {
return ISAErasureEncode<DataPartCount, ParityPartCount, TCodecTraits, TBlobType, TMutableBlobType>(EncodeGFTables_, blocks);
}
virtual ~TLrcIsa() = default;
private:
std::vector<TBlobType> FallbackToCodecDecode(
const std::vector<TBlobType>& blocks,
TPartIndexList erasedIndices) const override
{
return ISAErasureDecode<DataPartCount, ParityPartCount, TCodecTraits, TBlobType, TMutableBlobType>(
blocks,
std::move(erasedIndices),
this->GetXorGroups(),
GeneratorMatrix_);
}
std::vector<unsigned char> GeneratorMatrix_;
std::vector<unsigned char> EncodeGFTables_;
};
} // NErasure
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