lokinet/llarp/util/bits.hpp
Thomas Winget 7caa87862e standardize include format and pragma once
All #ifndef guards on headers have been removed, I think,
in favor of #pragma once

Headers are now included as `#include "filename"` if the included file
resides in the same directory as the file including it, or any
subdirectory therein.  Otherwise they are included as
`#include <project/top/dir/relative/path/filename>`

The above does not include system/os headers.
2021-03-09 19:01:41 -05:00

74 lines
1.6 KiB
C++

#pragma once
#include <bitset>
#include <cstddef>
#include <numeric>
#include <type_traits>
#include <limits>
#include <llarp/net/uint128.hpp>
#include <llarp/net/net_int.hpp>
namespace llarp
{
namespace bits
{
template <typename Int_t>
constexpr std::size_t
count_bits(Int_t i)
{
static_assert(std::is_integral<Int_t>::value, "Int_t should be an integer");
static_assert(std::is_unsigned<Int_t>::value, "Int_t should be unsigned");
return std::bitset<std::numeric_limits<Int_t>::digits>(i).count();
}
constexpr std::size_t
count_bits_128(const uint128_t& i)
{
return count_bits(i.upper) + count_bits(i.lower);
}
template <>
constexpr std::size_t
count_bits(huint32_t x)
{
return count_bits(x.h);
}
template <>
constexpr std::size_t
count_bits(nuint32_t x)
{
return count_bits(x.n);
}
template <>
constexpr std::size_t
count_bits(huint128_t x)
{
return count_bits_128(x.h);
}
template <>
constexpr std::size_t
count_bits(nuint128_t x)
{
return count_bits_128(x.n);
}
template <typename InputIt>
constexpr std::size_t
count_array_bits_impl(InputIt begin, InputIt end)
{
return std::accumulate(
begin, end, 0, [](auto acc, auto val) { return acc + count_bits(val); });
}
template <typename T>
constexpr std::size_t
count_array_bits(const T& array)
{
return count_array_bits_impl(std::begin(array), std::end(array));
}
} // namespace bits
} // namespace llarp