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#pragma once 
 
#include <util/system/compiler.h>
#include <util/system/types.h> 
 
#include <utility>

namespace NBench { 
    namespace NCpu { 
        struct TParams { 
            inline size_t Iterations() const noexcept { 
                return Iterations_; 
            } 
 
            const size_t Iterations_; 
        }; 
 
        using TUserFunc = void(TParams&); 
 
        struct TRegistar { 
            TRegistar(const char* name, TUserFunc func); 
 
            char Buf[128]; 
        }; 
    } 
 
    /**
     * Functions that states "I can read and write everywhere in memory".
     *
     * Use it to prevent optimizer from reordering or discarding memory writes prior to it's call,
     * and force memory reads after it's call.
     */
    void Clobber();

    /**
     * Forces whatever `p` points to be in memory and not in register.
     *
     * @param       Pointer to data.
     */
    template <typename T>
    void Escape(T* p);

#if defined(__GNUC__)
    Y_FORCE_INLINE void Clobber() {
        asm volatile("" 
                     : 
                     : 
                     : "memory"); 
    }
#elif defined(_MSC_VER)
    Y_FORCE_INLINE void Clobber() {
        _ReadWriteBarrier();
    }

#else
    Y_FORCE_INLINE void Clobber() {
    }
#endif

#if defined(__GNUC__)
    template <typename T>
    Y_FORCE_INLINE void Escape(T* p) {
        asm volatile("" 
                     : 
                     : "g"(p) 
                     : "memory"); 
    }
#else
    template <typename T>
    Y_FORCE_INLINE void Escape(T*) {
    }
#endif

    /**
     * Use this function to prevent unused variables elimination.
     *
     * @param       Unused variable (e.g. return value of benchmarked function).
     */
    template <typename T>
    Y_FORCE_INLINE void DoNotOptimize(T&& datum) { 
        ::DoNotOptimizeAway(std::forward<T>(datum));
    } 

    int Main(int argc, char** argv);
} 
 
#define Y_CPU_BENCHMARK(name, cnt)                              \
    namespace N_bench_##name {                                  \
        static void Run(::NBench::NCpu::TParams&);              \
        const ::NBench::NCpu::TRegistar benchmark(#name, &Run); \
    }                                                           \
    static void N_bench_##name::Run(::NBench::NCpu::TParams& cnt)