[llvm] [mlir] [Dwarf] Support `__ptrauth` qualifier in metadata nodes (PR #83862)

[Adrian Prantl via llvm-commits]

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@@ -1566,8 +1566,17 @@ Error MetadataLoader::MetadataLoaderImpl::parseOneMetadata(
       DWARFAddressSpace = Record[12] - 1;
 
     Metadata *Annotations = nullptr;
-    if (Record.size() > 13 && Record[13])
-      Annotations = getMDOrNull(Record[13]);
+    std::optional<DIDerivedType::PtrAuthData> PtrAuthData;
+
+    // Only look for annotations/ptrauth if both are allocated.
+    // If not, we can't tell which was intended to be embedded, as both ptrauth
+    // and annotations have been expected at Record[13] at various times.
+    if (Record.size() > 14) {
+      if (Record[13])
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adrian-prantl wrote:

This if  is redundant?

https://github.com/llvm/llvm-project/pull/83862