24 lines
492 B
C++
24 lines
492 B
C++
#ifndef OSRM_UTIL_MSB_HPP
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#define OSRM_UTIL_MSB_HPP
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#include <bit>
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#include <boost/assert.hpp>
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#include <limits>
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namespace osrm::util
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{
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template <typename T> std::size_t msb(T value)
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{
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BOOST_ASSERT(value > 0);
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static_assert(std::is_integral<T>::value && !std::is_signed<T>::value, "Integer required.");
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constexpr auto MSB_INDEX = std::numeric_limits<unsigned char>::digits * sizeof(T) - 1;
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return MSB_INDEX - std::countl_zero(value);
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}
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} // namespace osrm::util
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#endif
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