rocrand_threefry2x32_20.h

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/*
Copyright 2010-2011, D. E. Shaw Research.
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#ifndef ROCRAND_THREEFRY2X32_20_H_
#define ROCRAND_THREEFRY2X32_20_H_

#ifndef FQUALIFIERS
    #define FQUALIFIERS __forceinline__ __device__
#endif // FQUALIFIERS

#include "rocrand/rocrand_threefry2_impl.h"

namespace rocrand_device
{

class threefry2x32_20_engine : public threefry_engine2_base<uint2, unsigned int, 20>
{
public:
    typedef threefry_engine2_base<uint2, unsigned int, 20>::threefry_state_2 threefry2x32_20_state;

    FQUALIFIERS threefry2x32_20_engine(const unsigned long long seed        = 0,
                                       const unsigned long long subsequence = 0,
                                       const unsigned long long offset      = 0)
    {
        this->seed(seed, subsequence, offset);
    }

    FQUALIFIERS void seed(const unsigned long long seed        = 0,
                          const unsigned long long subsequence = 0,
                          const unsigned long long offset      = 0)
    {
        m_state.counter  = {0U, 0U};
        m_state.result   = {0U, 0U};
        m_state.substate = 0;

        m_state.key = {static_cast<unsigned int>(seed), static_cast<unsigned int>(seed >> 32)};

        this->discard_subsequence_impl(subsequence);
        this->discard(offset);
        m_state.result = this->threefry_rounds(m_state.counter, m_state.key);
    }

}; // threefry2x32_20_engine class

} // end namespace rocrand_device

typedef rocrand_device::threefry2x32_20_engine rocrand_state_threefry2x32_20;

FQUALIFIERS void rocrand_init(const unsigned long long       seed,
                              const unsigned long long       subsequence,
                              const unsigned long long       offset,
                              rocrand_state_threefry2x32_20* state)
{
    *state = rocrand_state_threefry2x32_20(seed, subsequence, offset);
}

FQUALIFIERS unsigned int rocrand(rocrand_state_threefry2x32_20* state)
{
    return state->next();
}

FQUALIFIERS uint2 rocrand2(rocrand_state_threefry2x32_20* state)
{
    return state->next2();
}

#endif // ROCRAND_THREEFRY2X32_20_H_