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

[Joshua Baehring 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;
+
+  static void testUnmapCallback(scudo::MemMapT &MemMap) {
+    scudo::u32 *Ptr = reinterpret_cast<scudo::u32 *>(MemMap.getBase());
+    *Ptr = MarkerBytes;
+  }
+
+  using Config = scudo::DefaultConfig;
+  using SecondaryConfig = scudo::SecondaryConfig<Config>;
+  using CacheConfig = SecondaryConfig::CacheConfig;
+  using CacheT = scudo::MapAllocatorCache<CacheConfig, testUnmapCallback>;
+
+  std::unique_ptr<CacheT> Cache = std::make_unique<CacheT>();
+
+  const scudo::uptr PageSize = scudo::getPageSizeCached();
+  static constexpr scudo::uptr DefaultAllocSize = scudo::uptr(1U) << 16;
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JoshuaMBa wrote:

Ok, I mainly used this size because this is the current minimum default size where the scudo allocator switches to the secondary allocator, but the choice was not influenced for any testing purposes.

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