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

[Christopher Ferris via llvm-commits]

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@@ -117,35 +127,46 @@ template <typename Config> class SizeClassAllocator64 {
     SmallerBlockReleasePageDelta =
         PagesInGroup * (1 + MinSizeClass / 16U) / 100;
 
+    RegionInfoManager.init(RegionInfoAllocator);
+
     u32 Seed;
     const u64 Time = getMonotonicTimeFast();
     if (!getRandom(reinterpret_cast<void *>(&Seed), sizeof(Seed)))
       Seed = static_cast<u32>(Time ^ (reinterpret_cast<uptr>(&Seed) >> 12));
 
     for (uptr I = 0; I < NumClasses; I++)
-      getRegionInfo(I)->RandState = getRandomU32(&Seed);
+      RegionInfoManager.getCurRegionInfo(I)->RandState = getRandomU32(&Seed);
 
     if (Config::getEnableContiguousRegions()) {
       ReservedMemoryT ReservedMemory = {};
+      // Block grouping requires the base address of a Region to be aligned
+      // with GrouopSize and pointer is compacted according to the offset to the
+      // base of a region so it always meets the requirement. As a result when
+      // the compaction is disabled, it relies on the base address to be
+      // aligned.
+      const uptr Alignment =
+          DisablePtrCompaction ? (1UL << GroupSizeLog) : PageSize;
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cferris1000 wrote:

Is there a way to add a DCHECK that would fail if CompactPtrT is set but pointer compaction is disabled?

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