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#pragma once

#include <cmath>
#include <cstdint>
#include <type_traits>

namespace mbgl {
namespace util {

// Computes the log2(x) rounded up to the next integer.
// (== number of bits required to store x)
uint32_t ceil_log2(uint64_t x);

template <typename T>
typename std::enable_if_t<std::is_floating_point<T>::value, T> log2(T x)
{
// log2() is producing wrong results on ARMv5 binaries
// running on ARMv7+ CPUs.
#if defined(__ANDROID__)
    return std::log(x) / M_LN2;
#else
    return std::log2(x);
#endif
}

} // namespace util
} // namespace mbgl