Check AVX2 support

gistfile1.txt

Linux:

$ cat /proc/cpuinfo | grep avx2
flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss 
ht syscall nx rdtscp lm constant_tsc nopl xtopology nonstop_tsc cpuid tsc_known_freq pni pclmulqdq ssse3 fma 
cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm 
3dnowprefetch invpcid_single pti fsgsbase tsc_adjust bmi1 avx2 smep bmi2 invpcid rdseed adx smap clflushopt 
xsaveopt xsavec dtherm arat pln pts


Mac:

$ gcc -mavx2 -dM -E - < /dev/null | egrep "AVX"
#define __AVX2__ 1
#define __AVX__ 1

Windows:

https://www.cpuid.com/softwares/cpu-z.html