This code path hasn't been maintained so no promises that it still works but here are the mappings:
m_padButtonMasks.PushBack(PadButtonMask(XINPUT_GAMEPAD_DPAD_UP, 0, -1));
m_padButtonMasks.PushBack(PadButtonMask(XINPUT_GAMEPAD_DPAD_DOWN, 0, +1));
m_padButtonMasks.PushBack(PadButtonMask(XINPUT_GAMEPAD_DPAD_LEFT, -1, 0));
m_padButtonMasks.PushBack(PadButtonMask(XINPUT_GAMEPAD_DPAD_RIGHT, +1, 0));
m_normalButtonMasks.PushBack(XINPUT_GAMEPAD_START);
m_normalButtonMasks.PushBack(XINPUT_GAMEPAD_BACK);
m_normalButtonMasks.PushBack(XINPUT_GAMEPAD_LEFT_THUMB);
m_normalButtonMasks.PushBack(XINPUT_GAMEPAD_RIGHT_THUMB);
m_normalButtonMasks.PushBack(XINPUT_GAMEPAD_LEFT_SHOULDER);
m_normalButtonMasks.PushBack(XINPUT_GAMEPAD_RIGHT_SHOULDER);
m_normalButtonMasks.PushBack(XINPUT_GAMEPAD_A);
m_normalButtonMasks.PushBack(XINPUT_GAMEPAD_B);
m_normalButtonMasks.PushBack(XINPUT_GAMEPAD_X);
m_normalButtonMasks.PushBack(XINPUT_GAMEPAD_Y);