Function OpenProcessorKey

Source/Windows/Common/CPUFeatures.cpp:15–22

namespace {

HKEY OpenProcessorKey(uint32_t Idx) {
  HKEY Out;
  auto Path = fextl::fmt::format("Hardware\\Description\\System\\CentralProcessor\\{}", Idx);
  if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, Path.c_str(), 0, KEY_READ, &Out)) {
    return nullptr;
  }
  return Out;
}

uint64_t ReadRegU64(HKEY Key, const char* Name) {
  uint64_t Value = 0;