An operating system uses non-bit aligned test masks to encode compound logical tests within the test mask. Generally, a bit within the test mask will indicate whether the test mask is a bit-aligned test mask or a non-bit-aligned test mask. If the system detects that the test mask in a non-bit-aligned test mask, the system will traverse the test mask to extract bit-aligned sub-masks and perform multi-level logical tests with the bit-aligned sub-masks. Such a system is particularly useful when performing a compound AND-OR logical test involving mutually exclusive event group flags.