[llvm] [MC] Allocate MCFragment with a bump allocator (PR #96402)

[Alexis Engelke via llvm-commits]

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@@ -136,6 +136,9 @@ class MCContext {
   /// objects.
   BumpPtrAllocator Allocator;
 
+  /// For MCFragment instances.
+  BumpPtrAllocator FragmentAllocator;
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aengelke wrote:

Any particular reasons to not reuse `Allocator`?

https://github.com/llvm/llvm-project/pull/96402