philox_constants.hpp

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//============================================================================
// MCKL/include/mckl/random/internal/philox_constants.hpp
//----------------------------------------------------------------------------
// MCKL: Monte Carlo Kernel Library
//----------------------------------------------------------------------------
// Copyright (c) 2013-2018, Yan Zhou
// All rights reserved.
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//============================================================================

#ifndef MCKL_RANDOM_INTERNAL_PHILOX_CONSTANTS_HPP
#define MCKL_RANDOM_INTERNAL_PHILOX_CONSTANTS_HPP

#include <mckl/random/internal/common.hpp>

namespace mckl {

namespace internal {

template <typename T, std::size_t, int = std::numeric_limits<T>::digits>
class PhiloxConstantsWeyl;

template <typename T>
class PhiloxConstantsWeyl<T, 2, 32>
{
  public:
    static constexpr T value[1] = {0x9E3779B9};
}; // class PhiloxConstantsWeyl

template <typename T>
class PhiloxConstantsWeyl<T, 4, 32>
{
  public:
    static constexpr T value[2] = {0x9E3779B9, 0xBB67AE85};
}; // class PhiloxConstantsWeyl

template <typename T>
class PhiloxConstantsWeyl<T, 2, 64>
{
  public:
    static constexpr T value[1] = {0x9E3779B97F4A7C15};
}; // class PhiloxConstantsWeyl

template <typename T>
class PhiloxConstantsWeyl<T, 4, 64>
{
  public:
    static constexpr T value[2] = {0x9E3779B97F4A7C15, 0xBB67AE8584CAA73B};
}; // class PhiloxConstantsWeyl

template <typename T, std::size_t, int = std::numeric_limits<T>::digits>
class PhiloxConstantsMultiplier;

template <typename T>
class PhiloxConstantsMultiplier<T, 2, 32>
{
  public:
    static constexpr T value[1] = {0xD256D193};
}; // class PhiloxConstantsMultiplier

template <typename T>
class PhiloxConstantsMultiplier<T, 4, 32>
{
  public:
    static constexpr T value[2] = {0xCD9E8D57, 0xD2511F53};
}; // class PhiloxConstantsMultiplier

template <typename T>
class PhiloxConstantsMultiplier<T, 2, 64>
{
  public:
    static constexpr T value[1] = {0xD2B74407B1CE6E93};
}; // class PhiloxConstantsMultiplier

template <typename T>
class PhiloxConstantsMultiplier<T, 4, 64>
{
  public:
    static constexpr T value[2] = {0xCA5A826395121157, 0xD2E7470EE14C6C93};
}; // class PhiloxConstantsMultiplier

} // namespace internal

template <typename T, std::size_t K>
class PhiloxConstants
{
  public:
    using weyl = internal::PhiloxConstantsWeyl<T, K>;
    using multiplier = internal::PhiloxConstantsMultiplier<T, K>;
}; // class PhiloxConstants

} // namespace mckl

#endif // MCKL_RANDOM_INTERNAL_PHILOX_CONSTANTS_HPP