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#ifndef KOKKOSBLAS2_TEAM_GEMV_SPEC_HPP_
#define KOKKOSBLAS2_TEAM_GEMV_SPEC_HPP_

#include <KokkosKernels_config.h>
#include <Kokkos_Core.hpp>
#include <Kokkos_ArithTraits.hpp>
#include <Kokkos_InnerProductSpaceTraits.hpp>

namespace KokkosBlas {
namespace Experimental {
namespace Impl {

template <class MT, class XV, class YV, int T>
struct team_gemv_tpl_spec_avail {
  constexpr static bool value = false;
};

// Unification and Specialization layer
template <class TeamType, class MatrixType, class XVector, class YVector, int T,
          bool tpl_spec_avail =
              team_gemv_tpl_spec_avail<MatrixType, XVector, YVector, T>::value>
struct TeamGEMV {
  static KOKKOS_INLINE_FUNCTION void team_gemv(
      const TeamType& team, const typename XVector::non_const_value_type& alpha,
      const MatrixType& A, const XVector& x,
      const typename YVector::non_const_value_type& beta, const YVector& y);
};

template <class TeamType, class MatrixType, class XVector, class YVector>
struct TeamGEMV<TeamType, MatrixType, XVector, YVector, 0, false> {
  typedef typename Kokkos::Details::InnerProductSpaceTraits<
      typename MatrixType::non_const_value_type>::dot_type dot_type;
  static KOKKOS_INLINE_FUNCTION void team_gemv(
      const TeamType& team, const typename XVector::non_const_value_type& alpha,
      const MatrixType& A, const XVector& x,
      const typename YVector::non_const_value_type& beta, const YVector& y) {
    const int N = A.extent(0);
    const int M = A.extent(1);

    Kokkos::parallel_for(Kokkos::TeamThreadRange(team, N), [&](const int& i) {
      dot_type Ax_i;
      Kokkos::parallel_reduce(
          Kokkos::ThreadVectorRange(team, M),
          [&](const int& j, dot_type& val) { val += A(i, j) * x(j); }, Ax_i);
      y(i) = beta * y(i) + alpha * Ax_i;
    });
  }
};

template <class TeamType, class MatrixType, class XVector, class YVector>
struct TeamGEMV<TeamType, MatrixType, XVector, YVector, -1, false> {
  typedef typename MatrixType::non_const_value_type value_type;
  typedef typename Kokkos::Details::InnerProductSpaceTraits<
      typename MatrixType::non_const_value_type>::dot_type dot_type;
  static KOKKOS_INLINE_FUNCTION void team_gemv(
      const TeamType& team, const typename XVector::non_const_value_type& alpha,
      const MatrixType& A, const XVector& x,
      const typename YVector::non_const_value_type& beta, const YVector& y) {
    const int N = A.extent(0);
    const int M = A.extent(1);

    Kokkos::parallel_for(Kokkos::TeamThreadRange(team, N), [&](const int& i) {
      dot_type Ax_i;
      Kokkos::parallel_reduce(
          Kokkos::ThreadVectorRange(team, M),
          [&](const int& j, dot_type& val) {
            val += Kokkos::ArithTraits<value_type>::conj(A(i, j)) * x(j);
          },
          Ax_i);
      y(i) = beta * y(i) + alpha * Ax_i;
    });
  }
};

template <class TeamType, class MatrixType, class XVector, class YVector>
struct TeamGEMV<TeamType, MatrixType, XVector, YVector, 1, false> {
  typedef typename Kokkos::Details::InnerProductSpaceTraits<
      typename MatrixType::non_const_value_type>::dot_type dot_type;
  static KOKKOS_INLINE_FUNCTION void team_gemv(
      const TeamType& team, const typename XVector::non_const_value_type& alpha,
      const MatrixType& A, const XVector& x,
      const typename YVector::non_const_value_type& beta, const YVector& y) {
    const int N = A.extent(1);
    const int M = A.extent(0);
    Kokkos::parallel_for(Kokkos::TeamThreadRange(team, N), [&](const int& i) {
      dot_type Ax_i;
      Kokkos::parallel_reduce(
          Kokkos::ThreadVectorRange(team, M),
          [&](const int& j, dot_type& val) { val += A(j, i) * x(j); }, Ax_i);
      y(i) = beta * y(i) + alpha * Ax_i;
    });
  }
};

template <class TeamType, class MatrixType, class XVector, class YVector>
struct TeamGEMV<TeamType, MatrixType, XVector, YVector, 2, false> {
  typedef typename MatrixType::non_const_value_type value_type;
  typedef
      typename Kokkos::Details::InnerProductSpaceTraits<value_type>::dot_type
          dot_type;
  static KOKKOS_INLINE_FUNCTION void team_gemv(
      const TeamType& team, const typename XVector::non_const_value_type& alpha,
      const MatrixType& A, const XVector& x,
      const typename YVector::non_const_value_type& beta, const YVector& y) {
    const int N = A.extent(1);
    const int M = A.extent(0);
    Kokkos::parallel_for(Kokkos::TeamThreadRange(team, N), [&](const int& i) {
      dot_type Ax_i;
      Kokkos::parallel_reduce(
          Kokkos::ThreadVectorRange(team, M),
          [&](const int& j, dot_type& val) {
            val += Kokkos::ArithTraits<value_type>::conj(A(j, i)) * x(j);
          },
          Ax_i);
      y(i) = beta * y(i) + alpha * Ax_i;
    });
  }
};
}  // namespace Impl
}  // namespace Experimental
}  // namespace KokkosBlas

#endif
