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

[Fangrui Song via llvm-commits]

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@@ -203,59 +203,57 @@ MCFragment::MCFragment(FragmentType Kind, bool HasInstructions)
 
 void MCFragment::destroy() {
   // First check if we are the sentinel.
-  if (Kind == FragmentType(~0)) {
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MaskRay wrote:

It looks like the `Kind == FragmentType(~0)` code path is now dead. I'll just delete this condition.

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