[clang] [lld] [llvm] [LTO][LLD] Prevent invalid LTO libfunc transforms (PR #164916)

[Teresa Johnson via cfe-commits]

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@@ -642,6 +658,12 @@ class LTO {
   // Diagnostic optimization remarks file
   LLVMRemarkFileHandle DiagnosticOutputFile;
 
+  // LibFuncs that could have been part of the LTO unit, but was not typically
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teresajohnson wrote:

I'm having a little trouble parsing the second clause here, do you want a comma before "typically"? Ah, I see that you do have the extra comma the other place where this was added. Also, is it 100% that because they were implemented in bitcode that they weren't extracted? I'm thinking of the ThinLTO case where they might be defined in another module. I see that mentioned in a FIXME elsewhere. Actually, I have a suggestion there, which would make this set exact even in the (currently in-process only) ThinLTO case.

https://github.com/llvm/llvm-project/pull/164916