[compiler-rt] [scudo] Update secondary cache time-based release logic. (PR #107507)

[Joshua Baehring via llvm-commits]

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@@ -633,6 +643,9 @@ class MapAllocatorCache {
   u16 LRUTail GUARDED_BY(Mutex) = 0;
   // The AvailableHead is the top of the stack of available entries
   u16 AvailableHead GUARDED_BY(Mutex) = 0;
+  // The DecommitBase is the least recently used entry that has not
+  // been released
+  u16 DecommitBase GUARDED_BY(Mutex) = 0;
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JoshuaMBa wrote:

I think changing the name to `LastUnreleasedEntry` makes the most sense since this is the entry we always want to release. I've updated the code accordingly.

https://github.com/llvm/llvm-project/pull/107507