[compiler-rt] [scudo] Add EnableMultiRegions mode (PR #98076)

[via llvm-commits]

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@@ -274,8 +347,24 @@ template <typename Config> class SizeClassAllocator64 {
     DCHECK_LT(ClassId, NumClasses);
     DCHECK_GT(Size, 0);
 
-    RegionInfo *Region = getRegionInfo(ClassId);
-    if (ClassId == SizeClassMap::BatchClassId) {
+    auto IsPtrInRegion = [](RegionInfo *Region,
+                            uptr Ptr) NO_THREAD_SAFETY_ANALYSIS {
+      // Thread-safety annotation doesn't support lambda. Use a runtime check
+      // instead.
+      Region->MMLock.assertHeld();
+      const uptr RegionEnd = Region->MemMapInfo.MemMap.getBase() +
+                             Region->MemMapInfo.MemMap.getCapacity();
+      return Ptr >= Region->RegionBeg && Ptr < RegionEnd;
+    };
+
+    // When multiple-regions is enabled, we need to sort the array to dispatch
+    // the blocks to different regions efficiently. Thus even we don't put
+    // BatchClass into groups, sorting is still necessary and it'll be handled
+    // later in the function.
+    // TODO: Reorder the use of variable
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ChiaHungDuan wrote:

Sorry, that's some private note for myself and which has been done.

https://github.com/llvm/llvm-project/pull/98076