[Lldb-commits] [lldb] Improve type and namespace lookup using parent chain (PR #108907)

[Greg Clayton via lldb-commits]

================
@@ -126,3 +126,62 @@ bool DWARFIndex::GetFullyQualifiedTypeImpl(
     return callback(die);
   return true;
 }
+
+void DWARFIndex::GetNamespacesWithParents(
+    ConstString name, llvm::ArrayRef<llvm::StringRef> parent_names,
+    llvm::function_ref<bool(DWARFDIE die)> callback) {
+  GetNamespaces(name, [&](DWARFDIE die) {
+    return ProcessDieMatchParentNames(name, parent_names, die, callback);
+  });
+}
+
+void DWARFIndex::GetTypesWithParents(
+    ConstString name, llvm::ArrayRef<llvm::StringRef> parent_names,
+    llvm::function_ref<bool(DWARFDIE die)> callback) {
+  GetTypes(name, [&](DWARFDIE die) {
+    return ProcessDieMatchParentNames(name, parent_names, die, callback);
+  });
+}
+
+bool DWARFIndex::ProcessDieMatchParentNames(
+    ConstString name, llvm::ArrayRef<llvm::StringRef> query_parent_names,
+    DWARFDIE die, llvm::function_ref<bool(DWARFDIE die)> callback) {
+  std::vector<lldb_private::CompilerContext> type_context =
+      die.GetTypeLookupContext();
+  if (type_context.empty()) {
+    // If both type_context and query_parent_names and empty we have a match.
+    // Otherwise, this one does not match and we keep on searching.
+    if (query_parent_names.empty())
+      return callback(die);
+    return true;
+  }
+
+  // Type lookup context includes the current DIE as the last element.
+  // so revert it for easy matching.
+  std::reverse(type_context.begin(), type_context.end());
+
+  // type_context includes the name of the current DIE while query_parent_names
----------------
clayborg wrote:

The .debug_names search is what returns results to `TypeQuery::ContextMatches`, but we should have functions that can do the same matching. The difference here in .debug_names is we are trying to live off only the contents of .debug_names without using and DIEs. `TypeQuery::ContextMatches` uses DIEs. So we might be able to unify some of the context matching once the context has been extracted from the .debug_names or from the DWARF, but that is about as far as we should go.

https://github.com/llvm/llvm-project/pull/108907