[llvm] [MC] Fix quadratic runtime within alignment boundary fragment relaxation (PR #176535)

[Fangrui Song via llvm-commits]

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@@ -1005,22 +1002,28 @@ void MCAssembler::layoutSection(MCSection &Sec) {
         F.getParent()->ContentStorage.resize(F.VarContentEnd);
       Offset += Size;
     } else {
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MaskRay wrote:

`} else if (F.getKind() == ...) {`

https://github.com/llvm/llvm-project/pull/176535