// Copyright (c) 2017-2024 Advanced Micro Devices, Inc. All rights reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

#ifndef ROCPRIM_TYPES_HPP_
#define ROCPRIM_TYPES_HPP_

#include <type_traits>

// Meta configuration for rocPRIM
#include "config.hpp"

#include "types/future_value.hpp"
#include "types/double_buffer.hpp"
#include "types/integer_sequence.hpp"
#include "types/key_value_pair.hpp"
#include "types/tuple.hpp"

/// \addtogroup utilsmodule
/// @{

BEGIN_ROCPRIM_NAMESPACE

namespace detail
{
// Define vector types that will be used by rocPRIM internally.
// We don't use HIP vector types because they don't generate correct
// load/store operations, see https://github.com/RadeonOpenCompute/ROCm/issues/341
#ifndef _MSC_VER
#define DEFINE_VECTOR_TYPE(name, base) \
\
struct alignas(sizeof(base) * 2) name##2 \
{ \
    typedef base vector_value_type __attribute__((ext_vector_type(2))); \
    union { \
        vector_value_type data; \
        struct { base x, y; }; \
    }; \
}; \
\
struct alignas(sizeof(base) * 4) name##4 \
{ \
    typedef base vector_value_type __attribute__((ext_vector_type(4))); \
    union { \
        vector_value_type data; \
        struct { base x, y, w, z; }; \
    }; \
};
#else
#define DEFINE_VECTOR_TYPE(name, base) \
\
struct alignas(sizeof(base) * 2) name##2 \
{ \
    typedef base vector_value_type; \
    union { \
        vector_value_type data; \
        struct { base x, y; }; \
    }; \
}; \
\
struct alignas(sizeof(base) * 4) name##4 \
{ \
    typedef base vector_value_type; \
    union { \
        vector_value_type data; \
        struct { base x, y, w, z; }; \
    }; \
};
#endif

#ifdef _MSC_VER
#pragma warning( push )
#pragma warning( disable : 4201 ) // nonstandard extension used: nameless struct/union
#endif
DEFINE_VECTOR_TYPE(char, char);
DEFINE_VECTOR_TYPE(short, short);
DEFINE_VECTOR_TYPE(int, int);
DEFINE_VECTOR_TYPE(longlong, long long);
#ifdef _MSC_VER
#pragma warning( pop )
#endif
// Takes a scalar type T and matches to a vector type based on NumElements.
template <class T, unsigned int NumElements>
struct make_vector_type
{
    using type = void;
};

#define DEFINE_MAKE_VECTOR_N_TYPE(name, base, suffix) \
template<> \
struct make_vector_type<base, suffix> \
{ \
    using type = name##suffix; \
};

#define DEFINE_MAKE_VECTOR_TYPE(name, base) \
\
template <> \
struct make_vector_type<base, 1> \
{ \
    using type = base; \
}; \
DEFINE_MAKE_VECTOR_N_TYPE(name, base, 2) \
DEFINE_MAKE_VECTOR_N_TYPE(name, base, 4)

DEFINE_MAKE_VECTOR_TYPE(char, char);
DEFINE_MAKE_VECTOR_TYPE(short, short);
DEFINE_MAKE_VECTOR_TYPE(int, int);
DEFINE_MAKE_VECTOR_TYPE(longlong, long long);

#undef DEFINE_VECTOR_TYPE
#undef DEFINE_MAKE_VECTOR_TYPE
#undef DEFINE_MAKE_VECTOR_N_TYPE

} // end namespace detail

/// \brief Empty type used as a placeholder, usually used to flag that given
/// template parameter should not be used.
struct empty_type {};

/// \brief Binary operator that takes two instances of empty_type, usually used
/// as nop replacement for the HIP-CPU back-end
struct empty_binary_op
{
    /// \brief Invocation operator.
    constexpr empty_type operator()(const empty_type&, const empty_type&) const { return empty_type{}; }
};

/// \brief A decomposer that must be passed to the radix sort algorithms when
/// sorting keys that are arithmetic types.
/// To sort custom types, a custom decomposer should be provided.
struct identity_decomposer
{};

/// \brief Half-precision floating point type
using half = ::__half;
/// \brief bfloat16 floating point type
using bfloat16 = ::hip_bfloat16;

// The lane_mask_type only exist at device side
#ifndef __AMDGCN_WAVEFRONT_SIZE
// When not compiling with hipcc, we're compiling with HIP-CPU
// TODO: introduce a ROCPRIM-specific macro to query this
#define __AMDGCN_WAVEFRONT_SIZE 64
#endif
/// \brief The lane_mask_type is an integer that contains one bit per thread.
///
/// The total number of bits is equal to the total number of threads in a
/// warp. Used to for warp-level operations.
/// \note This is defined only on the device side.
#if __AMDGCN_WAVEFRONT_SIZE == 32
using lane_mask_type = unsigned int;
#elif __AMDGCN_WAVEFRONT_SIZE == 64
using lane_mask_type = unsigned long long int;
#endif

/// \brief Native half-precision floating point type
#ifdef __HIP_CPU_RT__
using native_half = half;
#else
using native_half = _Float16;
#endif

/// \brief native bfloat16 type
#ifdef __HIP_CPU_RT__
// TODO: Find a better type
using native_bfloat16 = bfloat16;
#else
using native_bfloat16 = bfloat16;
#endif

END_ROCPRIM_NAMESPACE

/// @}
// end of group utilsmodule

#endif // ROCPRIM_TYPES_HPP_
