math.hpp
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	//===-- rosa/support/math.hpp ------------------------------------ C++ --===//
	//
	// The RoSA Framework
	//
	//===----------------------------------------------------------------------===//
	///
	/// \file rosa/support/math.hpp
	///
	/// \author David Juhasz (david.juhasz@tuwien.ac.at)
	///
	/// \date 2017
	///
	/// \brief Math helpers.
	///
	//===----------------------------------------------------------------------===//

	#ifndef ROSA_SUPPORT_MATH_HPP
	#define ROSA_SUPPORT_MATH_HPP

	#include <cmath>
	#include <cstdlib>
	#include <limits>
	#include <type_traits>

	namespace rosa {

	/// Computes log base 2 of a number.
	///
	/// \param N the number to compute log base 2 for
	///
	/// \return log base 2 of \p N
	constexpr size_t log2(const size_t N) {
	return ((N < 2) ? 1 : 1 + log2(N / 2));
	}

	/// Tells the next representable floating point value.
	///
	/// \tparam T type to operate on
	///
	/// \note The second type argument enforces \p T being a floating point type,
	/// always use the default value!
	///
	/// \param V value to which find the next representable one
	///
	/// \return the next representable value of type \p T after value \p V
	///
	/// \pre Type \p T must be a floating point type, which is enforced by
	/// `std::enable_if` in the second type argument.
	template <typename T,
	typename = std::enable_if_t<std::is_floating_point<T>::value>>
	T nextRepresentableFloatingPoint(const T V) {
	return std::nextafter(V, std::numeric_limits<T>::infinity());
	}

	} // End namespace rosa

	#endif // ROSA_SUPPORT_MATH_HPP