[clang] [InstallAPI] Collect frontend attributes & ObjCInterface decls (PR #83378)

[Juergen Ributzka via cfe-commits]

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@@ -16,6 +16,74 @@ using namespace llvm::MachO;
 
 namespace clang::installapi {
 
+GlobalRecord *FrontendRecordsSlice::addGlobal(
+    StringRef Name, RecordLinkage Linkage, GlobalRecord::Kind GV,
+    const clang::AvailabilityInfo Avail, const Decl *D, const HeaderType Access,
+    SymbolFlags Flags) {
+
+  auto *GR = llvm::MachO::RecordsSlice::addGlobal(Name, Linkage, GV, Flags);
+  if (!FrontendRecords.contains(GR))
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ributzka wrote:

You could optimize this a bit by always inserting. `insert` doesn't change anything if the key already exists.

https://github.com/llvm/llvm-project/pull/83378