code: func haveAVX2() bool {
  	mfi, _, _, _ := cpuid(0)
  
  	// Check AVX2, AVX2 requires OS support, but BMI1/2 don't.
  	if mfi >= 7 && haveAVX() {
  		_, ebx, _, _ := cpuidex(7, 0)
  		return (ebx & 0x00000020) != 0
  	}
  	return false
  }
docs: // haveAVX2 returns true when there is AVX2 support