How to create a DLL in VC++ and use Assembly code in it?

Create a DLL in VC++ and use assembly code in it.
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sysinfo.h

#include
extern "C" __declspec(dllexport) int __stdcall getCPUFamily());

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sysinfo.cpp

#include "SysInfo.h"
extern "C" __declspec(dllexport) int __stdcall getCPUFamily() {
    int retVal;
 //This is how to use assembly code
    _asm {
        mov eax, 1
        cpuid
        mov retVal, eax
    }

    return (retVal >> 8);
}