IGameInputDevice::GetControllerAxisLabels

uint32_t GetControllerAxisLabels(
    uint32_t labelArrayCount,
    GameInputLabel* labelArray
);

uint32_t axisCount = device->GetControllerAxisCount();
std::vector<GameInputLabel> axisLabels(axisCount);
axisLabels.resize(device->GetControllerAxisLabels(axisCount, axisLabels.data()));

std::vector<float> axisStates(reading->GetControllerAxisCount());
reading->GetControllerAxisState(static_cast<uint32_t>(axisStates.size()), axisStates.data());

for (size_t i = 0; i < axisLabels.size() && i < axisStates.size(); ++i)
{
    // axisLabels[i] is the label of the axis whose value is axisStates[i].
}