[Reflection] Support OpaqueExistential in RecordTypeInfo::readExtraInhabitantIndex

Author: kastiglione

stdlib/public/Reflection/TypeLowering.cpp

@@ -260,10 +260,19 @@ bool RecordTypeInfo::readExtraInhabitantIndex(remote::MemoryReader &reader,
                                               int *extraInhabitantIndex) const {
   switch (SubKind) {
   case RecordKind::Invalid:
-  case RecordKind::OpaqueExistential:
   case RecordKind::ClosureContext:
     return false;
 
+  case RecordKind::OpaqueExistential: {
+    if (Fields.size() != 1) {
+      return false;
+    }
+    auto metadata = Fields[0];
+    auto metadataFieldAddress = address + metadata.Offset;
+    return metadata.TI.readExtraInhabitantIndex(
+      reader, metadataFieldAddress, extraInhabitantIndex);
+  }
+
   case RecordKind::ThickFunction: {
     if (Fields.size() != 2) {
       return false;