- check that tag distinctess checks are actually reached (it was previously verified manually by
looking at the now-removed printf output)
- check that only non-reserved tags are used
- check that all of non-reserved tags are used
- print tag usage statistics at the end of run
To run them, connect an MTE-enabled device via adb and execute `atest HMallocTest:MemtagTest`.
Since these tests are not deterministic (and neither is hardened_malloc itself), it's better to run
them multiple times, e.g. `atest --iterations 30 HMallocTest:MemtagTest`.
There are also CTS tests that are useful for checking correctness of the Android integration:
`atest CtsTaggingHostTestCases`