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#ifndef ROCPRIM_THREAD_THREAD_LOAD_HPP_
#define ROCPRIM_THREAD_THREAD_LOAD_HPP_

#include "../config.hpp"

BEGIN_ROCPRIM_NAMESPACE

enum cache_load_modifier : int
{
    load_default,   ///< Default (no modifier)
    load_ca,        ///< Cache at all levels
    load_cg,        ///< Cache at global level
    load_cs,        ///< Cache streaming (likely to be accessed once)
    load_cv,        ///< Cache as volatile (including cached system lines)
    load_ldg,       ///< Cache as texture
    load_volatile,  ///< Volatile (any memory space)
};

namespace detail
{

template<cache_load_modifier MODIFIER = load_default, typename T>
ROCPRIM_DEVICE __forceinline__ T AsmThreadLoad(void * ptr)
{
    T retval = 0;
    __builtin_memcpy(&retval, ptr, sizeof(T));
    return retval;
}

#if ROCPRIM_THREAD_LOAD_USE_CACHE_MODIFIERS == 1

// Important for syncing. Check section 9.2.2 or 7.3 in the following document
// http://developer.amd.com/wordpress/media/2013/12/AMD_GCN3_Instruction_Set_Architecture_rev1.1.pdf
#define ROCPRIM_ASM_THREAD_LOAD(cache_modifier,                                                                \
                               llvm_cache_modifier,                                                           \
                               type,                                                                          \
                               interim_type,                                                                  \
                               asm_operator,                                                                  \
                               output_modifier,                                                               \
                               wait_cmd)                                                                      \
    template<>                                                                                                \
    ROCPRIM_DEVICE __forceinline__ type AsmThreadLoad<cache_modifier, type>(void * ptr)                        \
    {                                                                                                         \
        interim_type retval;                                                                                  \
        asm volatile(#asm_operator " %0, %1 " llvm_cache_modifier : "=" #output_modifier(retval) : "v"(ptr)); \
        asm volatile("s_waitcnt " wait_cmd "(%0)" : : "I"(0x00));                                             \
        return retval;                                                                                        \
    }

// TODO Add specialization for custom larger data types
#define ROCPRIM_ASM_THREAD_LOAD_GROUP(cache_modifier, llvm_cache_modifier, wait_cmd)                                  \
    ROCPRIM_ASM_THREAD_LOAD(cache_modifier, llvm_cache_modifier, int8_t, int16_t, flat_load_sbyte, v, wait_cmd);      \
    ROCPRIM_ASM_THREAD_LOAD(cache_modifier, llvm_cache_modifier, int16_t, int16_t, flat_load_sshort, v, wait_cmd);    \
    ROCPRIM_ASM_THREAD_LOAD(cache_modifier, llvm_cache_modifier, uint8_t, uint16_t, flat_load_ubyte, v, wait_cmd);    \
    ROCPRIM_ASM_THREAD_LOAD(cache_modifier, llvm_cache_modifier, uint16_t, uint16_t, flat_load_ushort, v, wait_cmd);  \
    ROCPRIM_ASM_THREAD_LOAD(cache_modifier, llvm_cache_modifier, uint32_t, uint32_t, flat_load_dword, v, wait_cmd);   \
    ROCPRIM_ASM_THREAD_LOAD(cache_modifier, llvm_cache_modifier, float, uint32_t, flat_load_dword, v, wait_cmd);      \
    ROCPRIM_ASM_THREAD_LOAD(cache_modifier, llvm_cache_modifier, uint64_t, uint64_t, flat_load_dwordx2, v, wait_cmd); \
    ROCPRIM_ASM_THREAD_LOAD(cache_modifier, llvm_cache_modifier, double, uint64_t, flat_load_dwordx2, v, wait_cmd);

// [HIP-CPU] MSVC: erronous inline assembly specification (Triggers error C2059: syntax error: 'volatile')
#ifndef __HIP_CPU_RT__
#if defined(__gfx940__) || defined(__gfx941__) || defined(__gfx942__)
ROCPRIM_ASM_THREAD_LOAD_GROUP(load_ca, "sc0", "");
ROCPRIM_ASM_THREAD_LOAD_GROUP(load_cg, "sc1", "");
ROCPRIM_ASM_THREAD_LOAD_GROUP(load_cv, "sc0 sc1", "vmcnt");
ROCPRIM_ASM_THREAD_LOAD_GROUP(load_volatile, "sc0 sc1", "vmcnt");
#else
ROCPRIM_ASM_THREAD_LOAD_GROUP(load_ca, "glc", "");
ROCPRIM_ASM_THREAD_LOAD_GROUP(load_cg, "glc slc", "");
ROCPRIM_ASM_THREAD_LOAD_GROUP(load_cv, "glc", "vmcnt");
ROCPRIM_ASM_THREAD_LOAD_GROUP(load_volatile, "glc", "vmcnt");
#endif

// TODO find correct modifiers to match these
ROCPRIM_ASM_THREAD_LOAD_GROUP(load_ldg, "", "");
ROCPRIM_ASM_THREAD_LOAD_GROUP(load_cs, "", "");
#endif // __HIP_CPU_RT__

#endif

}

/// \brief Store data using the default load instruction. No support for cache modified stores yet
/// \tparam MODIFIER        - Value in enum for determine which type of cache store modifier to be used
/// \tparam InputIteratorT - Type of Output Iterator
/// \param itr [in]         - Iterator to location where data is to be stored
/// \return Data that is loaded from memory
template <
    cache_load_modifier MODIFIER = load_default,
    typename InputIteratorT>
ROCPRIM_DEVICE ROCPRIM_INLINE
typename std::iterator_traits<InputIteratorT>::value_type
thread_load(InputIteratorT itr)
{
    using T = typename std::iterator_traits<InputIteratorT>::value_type;
    T retval = thread_load<MODIFIER>(&(*itr));
    return *itr;
}

/// \brief Load data using the default load instruction. No support for cache modified loads yet
/// \tparam MODIFIER        - Value in enum for determine which type of cache store modifier to be used
/// \tparam T               - Type of Data to be loaded
/// \param ptr [in] - Pointer to data to be loaded
/// \return Data that is loaded from memory
template <
    cache_load_modifier MODIFIER = load_default,
    typename T>
ROCPRIM_DEVICE ROCPRIM_INLINE
T thread_load(T* ptr)
{
#ifndef __HIP_CPU_RT__
    return detail::AsmThreadLoad<MODIFIER, T>(ptr);
#else
    T retval;
    std::memcpy(&retval, ptr, sizeof(T));
    return retval;
#endif
}

END_ROCPRIM_NAMESPACE

#endif
