Allocator: Calculate flex size with the correct number of elements

This was scaling the flexbitset that was used incorrectly.
FEX-Emu · Jan 24, 2025 · 668a702 · 668a702
1 parent fab8506
commit 668a702
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Showing 2 changed files with 5 additions and 2 deletions.
diff --git a/FEXCore/Source/Utils/Allocator/64BitAllocator.cpp b/FEXCore/Source/Utils/Allocator/64BitAllocator.cpp
@@ -110,7 +110,7 @@ class OSAllocator_64Bit final : public Alloc::HostAllocator {
       // 0x100'0000 Pages
       // 1 bit per page for tracking means 0x20'0000 (Pages / 8) bytes of flex space
       // Which is 2MB of tracking
-      uint64_t NumElements = (Size >> FEXCore::Utils::FEX_PAGE_SHIFT) * sizeof(FlexBitElementType);
+      uint64_t NumElements = (Size >> FEXCore::Utils::FEX_PAGE_SHIFT);
       return sizeof(LiveVMARegion) + FEXCore::FlexBitSet<FlexBitElementType>::Size(NumElements);
     }
 

diff --git a/FEXCore/Source/Utils/Allocator/FlexBitSet.h b/FEXCore/Source/Utils/Allocator/FlexBitSet.h
@@ -145,9 +145,12 @@ struct FlexBitSet final {
     return Get(Element);
   }
 
-  static size_t Size(uint64_t Elements) {
+  static size_t SizeBits(uint64_t Elements) {
     return std::max(FEXCore::AlignUp(Elements / MinimumSizeBits, MinimumSizeBits), MinimumSizeBits);
   }
+  static size_t Size(uint64_t Elements) {
+    return SizeBits(Elements) / MinimumSizeBits;
+  }
 };
 
 static_assert(sizeof(FlexBitSet<uint64_t>) == 0, "This needs to be a flex member");