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

[Fangrui Song via llvm-commits]

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@@ -5145,19 +5149,30 @@ bool LLParser::parseDIDerivedType(MDNode *&Result, bool IsDistinct) {
   OPTIONAL(flags, DIFlagField, );                                              \
   OPTIONAL(extraData, MDField, );                                              \
   OPTIONAL(dwarfAddressSpace, MDUnsignedField, (UINT32_MAX, UINT32_MAX));      \
-  OPTIONAL(annotations, MDField, );
+  OPTIONAL(annotations, MDField, );                                            \
+  OPTIONAL(ptrAuthKey, MDUnsignedField, (0, 7));                               \
+  OPTIONAL(ptrAuthIsAddressDiscriminated, MDBoolField, );                      \
+  OPTIONAL(ptrAuthExtraDiscriminator, MDUnsignedField, (0, 0xffff));           \
+  OPTIONAL(ptrAuthIsaPointer, MDBoolField, );                                  \
+  OPTIONAL(ptrAuthAuthenticatesNullValues, MDBoolField, );
   PARSE_MD_FIELDS();
 #undef VISIT_MD_FIELDS
 
   std::optional<unsigned> DWARFAddressSpace;
   if (dwarfAddressSpace.Val != UINT32_MAX)
     DWARFAddressSpace = dwarfAddressSpace.Val;
+  std::optional<DIDerivedType::PtrAuthData> PtrAuthData;
+  if (ptrAuthKey.Val)
+    PtrAuthData = DIDerivedType::PtrAuthData(
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MaskRay wrote:

Nit: `emplace` https://en.cppreference.com/w/cpp/utility/optional/emplace

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