[llvm] [DebugInfo] Make DIArgList inherit from Metadata and always unique (PR #72147)

[Jeremy Morse via llvm-commits]

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@@ -1975,13 +1974,12 @@ void ModuleBitcodeWriter::writeDIMacroFile(const DIMacroFile *N,
 }
 
 void ModuleBitcodeWriter::writeDIArgList(const DIArgList *N,
-                                         SmallVectorImpl<uint64_t> &Record,
-                                         unsigned Abbrev) {
+                                         SmallVectorImpl<uint64_t> &Record) {
   Record.reserve(N->getArgs().size());
   for (ValueAsMetadata *MD : N->getArgs())
     Record.push_back(VE.getMetadataID(MD));
 
-  Stream.EmitRecord(bitc::METADATA_ARG_LIST, Record, Abbrev);
+  Stream.EmitRecord(bitc::METADATA_ARG_LIST, Record);
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jmorse wrote:

For my understanding, what are the implications of not having an abbrev here -- will we end up with a potentially suboptimal encoding or something?

https://github.com/llvm/llvm-project/pull/72147