DenseHashMap and PrehashMap are the open-addressed, linear-probing maps behind
the texture cache, the shader managers and the software renderer's
sampler/drawpixel caches, and had no coverage.
Writing the tests turned up a latent hang. Removal leaves tombstones, which
occupy probe slots exactly like live entries, but the load factor check only
looked at count_. So a workload that inserts and removes distinct keys keeps
count_ low forever while REMOVED fills the table, and no Grow is ever triggered.
Once there is no FREE bucket left, a lookup for a missing key has nothing to
terminate on - and the probe loops don't break out after their "Hit full"
assert, which is compiled out in release builds. The test reproduced it as a
hard hang in about a second.
Two fixes: count tombstones towards the load factor (rebuilding in place when
the load is mostly tombstones, growing otherwise), and make the probe loops
return instead of spinning if they ever do wrap all the way around.
Not reachable today - nothing in GPU/ calls Remove() on these maps, and
Maintain(), which exists to rebuild when tombstones pile up, is never called
anywhere. But Remove() is public API and the first caller to use it in a loop
would have hit an unexplained freeze.
Tests cover insert/get/miss/remove/size, tombstones not cutting a probe chain,
Iterate visiting exactly the live entries, Clear, growth past the initial
capacity, Rebuild compacting, a 20000-operation differential test against
std::unordered_map, and the tombstone churn above. PrehashMap gets the same
treatment.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GZq8ZtJmFY7bkX5FVkr3P9
* Rename LogType to Log
* Explicitly use the Log:: enum when logging. Allows for autocomplete when editing.
* Mac/ARM64 buildfix
* Do the same with the hle result log macros
* Rename the log names to mixed case while at it.
* iOS buildfix
* Qt buildfix attempt, ARM32 buildfix
