[lldb][gnustep][PDB] Add special handling for ObjC built-in types eBasicTypeObjCID and eBasicTypeObjCSel

Author: weliveindetail

lldb/source/Plugins/SymbolFile/PDB/PDBASTParser.cpp

@@ -756,12 +756,32 @@ lldb::TypeSP PDBASTParser::CreateLLDBTypeFromPDBType(const PDBSymbol &type) {
     auto *pointer_type = llvm::dyn_cast<PDBSymbolTypePointer>(&type);
     assert(pointer_type);
 
-    SymbolFile *symbol_file = m_ast.GetSymbolFile();
+    auto *symbol_file = static_cast<SymbolFilePDB *>(m_ast.GetSymbolFile());
     if (!symbol_file)
       return nullptr;
 
-    Type *pointee_type = symbol_file->ResolveTypeUID(
-        pointer_type->getPointeeType()->getSymIndexId());
+    auto pdb_pointee_type = pointer_type->getPointeeType()->getSymIndexId();
+    if (symbol_file->IsObjCBuiltinTypeId(pdb_pointee_type)) {
+      // Clang emits id as objc_object* and we fill in the built-in "id" type
+      CompilerType id_type = m_ast.GetBasicType(eBasicTypeObjCID);
+      AddSourceInfoToDecl(type, decl);
+      return symbol_file->MakeType(
+          pointer_type->getSymIndexId(), ConstString("id"),
+          pointer_type->getLength(), nullptr, pdb_pointee_type,
+          lldb_private::Type::eEncodingIsUID, decl, id_type,
+          lldb_private::Type::ResolveState::Full);
+    }
+    if (symbol_file->IsObjCBuiltinTypeSel(pdb_pointee_type)) {
+      CompilerType id_type = m_ast.GetBasicType(eBasicTypeObjCSel);
+      AddSourceInfoToDecl(type, decl);
+      return symbol_file->MakeType(
+          pointer_type->getSymIndexId(), ConstString("SEL"),
+          pointer_type->getLength(), nullptr, pdb_pointee_type,
+          lldb_private::Type::eEncodingIsUID, decl, id_type,
+          lldb_private::Type::ResolveState::Full);
+    }
+
+    Type *pointee_type = symbol_file->ResolveTypeUID(pdb_pointee_type);
     if (!pointee_type)
       return nullptr;
 

lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.cpp

@@ -2088,3 +2088,31 @@ bool SymbolFilePDB::IsaNSObjectOrNSProxy(
   auto *pdb_base_udt = llvm::dyn_cast<PDBSymbolTypeUDT>(pdb_base_raw_up.get());
   return IsaNSObjectOrNSProxy(*pdb_base_udt);
 }
+
+bool SymbolFilePDB::IsObjCBuiltinTypeId(user_id_t sym_uid) const {
+  std::unique_ptr<PDBSymbol> pdb_sym_up = m_session_up->getSymbolById(sym_uid);
+  if (pdb_sym_up->getSymTag() != PDB_SymType::UDT)
+    return false;
+
+  auto *pdb_sym_udt = llvm::dyn_cast<PDBSymbolTypeUDT>(pdb_sym_up.get());
+  if (pdb_sym_udt->getName() != "id" &&
+      pdb_sym_udt->getName() != "objc_object")
+    return false;
+
+  return true;
+}
+
+bool SymbolFilePDB::IsObjCBuiltinTypeSel(user_id_t sym_uid) const {
+  std::unique_ptr<PDBSymbol> pdb_sym_up = m_session_up->getSymbolById(sym_uid);
+  if (pdb_sym_up->getSymTag() != PDB_SymType::UDT)
+    return false;
+
+  auto *pdb_sym_udt = llvm::dyn_cast<PDBSymbolTypeUDT>(pdb_sym_up.get());
+  if (pdb_sym_udt->getName() != "objc_selector")
+    return false;
+
+  // TODO: ObjC selectors exist only for ObjC functions and they never occur
+  // freestanding. Thus, we know that all instances of this UDT are defined
+  // within ObjCInterfaceDecls. Can we add a check for that?
+  return true;
+}

lldb/source/Plugins/SymbolFile/PDB/SymbolFilePDB.h

@@ -170,6 +170,8 @@ class SymbolFilePDB : public lldb_private::SymbolFileCommon {
   void DumpClangAST(lldb_private::Stream &s) override;
 
   bool IsaNSObjectOrNSProxy(const llvm::pdb::PDBSymbolTypeUDT &udt) const;
+  bool IsObjCBuiltinTypeId(lldb::user_id_t sym_uid) const;
+  bool IsObjCBuiltinTypeSel(lldb::user_id_t sym_uid) const;
 
 private:
   struct SecContribInfo {