[clang] [llvm] [LFI] Add MCLFIRewriter infrastructure (PR #172906)

[Alexis Engelke via cfe-commits]

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@@ -307,6 +310,10 @@ class LLVM_ABI MCStreamer {
     return StartTokLocPtr ? *StartTokLocPtr : SMLoc();
   }
 
+  void setLFIRewriter(MCLFIRewriter *Exp) { LFIRewriter.reset(Exp); }
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aengelke wrote:

Should take unique_ptr. I assume this function is only called on LFI targets and otherwise the rewriter is null?

https://github.com/llvm/llvm-project/pull/172906