[llvm] MC: Store MCRelaxableFragment MCInst out-of-line (PR #147229)

[Alexis Engelke via llvm-commits]

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@@ -431,16 +428,38 @@ class MCDataFragment : public MCEncodedFragment {
 ///
 class MCRelaxableFragment : public MCEncodedFragment {
   /// The instruction this is a fragment for.
-  MCInst Inst;
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aengelke wrote:

X86MCInstLower::Lower calls setFlags and with allowEnhancedRelaxation, these can end up in a relaxable fragment?

https://github.com/llvm/llvm-project/pull/147229