[compiler-rt] [scudo] Added test fixture for cache tests. (PR #102230)

[Christopher Ferris via llvm-commits]

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@@ -265,3 +265,99 @@ TEST_F(MapAllocatorWithReleaseTest, SecondaryThreadsRace) {
   Allocator->getStats(&Str);
   Str.output();
 }
+
+struct MapAllocatorCacheTest : public Test {
+  static constexpr scudo::u32 MarkerBytes = 0xDEADBEEF;
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cferris1000 wrote:

Maybe a slightly better name would be UnmappedMarker. It's not really a bytes value, so it was confusing because I originally assumed it was a single byte pattern.

https://github.com/llvm/llvm-project/pull/102230