Canadian_Republican Canadian_Republican - 4 months ago 31
C++ Question

Within my c++ program is there a way to check if the CPU has AES-NI

I want to be able to check if a CPU has AES-NI available to it with C++ code on windows. (GCC)

I found a solution to this written in C# with visual studio.

Test for AES-NI instructions from C#

private static bool IsAESNIPresent()
byte[] sn = new byte[16]; // !!! Here were 8 bytes

if (!ExecuteCode(ref sn))
return false;

var ecx = BitConverter.ToUInt32(sn, 8);
return (ecx & (1 << 25)) != 0;

Is there an easy way to do the same with c++? (GCC)


There is some code in pycrypto that seems to be applicable. I took the essential parts of the code for testing:

#include <cpuid.h>
#include <stdint.h>
#include <stdio.h>

int main()
    uint32_t eax, ebx, ecx, edx;

    eax = ebx = ecx = edx = 0;
    __get_cpuid(1, &eax, &ebx, &ecx, &edx);
    printf("%08x %08x %08x %08x\n", eax, ebx, ecx, edx);
    printf("Has AES-NI: %d\n", (ecx & bit_AES) > 0);

    return 0;

The results seem to correspond with the information provided by /proc/cpuinfo or information provided by intel web pages.

For other capabilities, see clang documentation