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// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#pragma once
#include "bitencode64.h"
#include <vespa/searchlib/util/comprfile.h>
#include <vespa/searchlib/bitcompression/compression.h>
namespace search
{
namespace fakedata
{
template <bool bigEndian>
class BitDecode64 : public bitcompression::DecodeContext64<bigEndian>
{
private:
const uint64_t *_comprBase;
int _bitOffsetBase;
typedef bitcompression::DecodeContext64<bigEndian> ParentClass;
public:
using ParentClass::_val;
using ParentClass::_valI;
using ParentClass::_preRead;
using ParentClass::_cacheInt;
typedef typename bitcompression::DecodeContext64<bigEndian>::EC EC;
BitDecode64(const uint64_t *compr,
int bitOffset)
: bitcompression::DecodeContext64<bigEndian>(compr, bitOffset),
_comprBase(compr),
_bitOffsetBase(bitOffset)
{
}
typedef bitcompression::DecodeContext64<bigEndian> DC;
void
seek(uint64_t offset)
{
offset += _bitOffsetBase;
const uint64_t *compr = _comprBase + (offset / 64);
int bitOffset = offset & 63;
_valI = compr + 1;
_val = 0;
_cacheInt = EC::bswap(*compr);
_preRead = 64 - bitOffset;
uint32_t length = 64;
UC64_READBITS(_val, _valI, _preRead, _cacheInt, EC);
}
uint64_t
getOffset() const
{
return 64 * (_valI - _comprBase - 1) - this->_preRead -
_bitOffsetBase;
}
uint64_t
getOffset(const uint64_t *valI, int preRead) const
{
return 64 * (valI - _comprBase - 1) - preRead - _bitOffsetBase;
}
const uint64_t *
getComprBase() const
{
return _comprBase;
}
int
getBitOffsetBase() const
{
return _bitOffsetBase;
}
};
extern template class BitDecode64<true>;
extern template class BitDecode64<false>;
typedef BitDecode64<true> BitDecode64BE;
typedef BitDecode64<false> BitDecode64LE;
} // namespace fakedata
} // namespace search
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