[lld] [llvm] [lld][AArch64][Build Attributes] Add support for converting AArch64 Build Attributes to GNU Properties (PR #131990)

[Peter Smith via llvm-commits]

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@@ -694,6 +696,10 @@ struct Ctx : CommonLinkerContext {
   llvm::raw_fd_ostream openAuxiliaryFile(llvm::StringRef, std::error_code &);
 
   ArrayRef<uint8_t> aarch64PauthAbiCoreInfo;
+
+  // AArch64 Build Attributes data
+  std::optional<llvm::BuildAttributeSubSection> mergedPauthSubSection;
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smithp35 wrote:

I think that using a raw BuildAttributeSubSection here is only worthwhile if that data structure has a generic join(otherBuildAttributes) combine option. That can combine all the tags in the generic API.

If that doesn't exist it is better to do what Oliver suggests and make structures with just what you need as these will be simpler to operate on.

I think for the existing attributes we don't actually need the merged subsections as we can map the existing attributes into f->andFeatures and the PAuth equivalent. Then let the existing code in Driver.cpp do the merging of these.

https://github.com/llvm/llvm-project/pull/131990