Clean-up irep-id emptyness checks in java-bytecode

Author: peterschrammel

src/java_bytecode/java_bytecode_convert_method.cpp

@@ -2309,7 +2309,7 @@ codet java_bytecode_convert_methodt::convert_instructions(
     if(v.is_parameter)
       continue;
     // Skip anonymous variables:
-    if(v.symbol_expr.get_identifier()==irep_idt())
+    if(v.symbol_expr.get_identifier().empty())
       continue;
     auto &block=get_block_for_pcrange(
       root,

src/java_bytecode/java_bytecode_language.cpp

@@ -203,9 +203,9 @@ static void get_virtual_method_targets(
   assert(called_function.id()==ID_virtual_function);
 
   const auto &call_class=called_function.get(ID_C_class);
-  assert(call_class!=irep_idt());
+  assert(!call_class.empty());
   const auto &call_basename=called_function.get(ID_component_name);
-  assert(call_basename!=irep_idt());
+  assert(!call_basename.empty());
 
   auto old_size=needed_methods.size();
 
@@ -218,7 +218,7 @@ static void get_virtual_method_targets(
         call_basename,
         child_class,
         symbol_table);
-    if(child_method!=irep_idt())
+    if(!child_method.empty())
       needed_methods.push_back(child_method);
   }
 
@@ -231,7 +231,7 @@ static void get_virtual_method_targets(
         call_basename,
         parent_class_id,
         symbol_table);
-    if(parent_method!=irep_idt())
+    if(!parent_method.empty())
     {
       needed_methods.push_back(parent_method);
       break;

src/java_bytecode/java_bytecode_parse_tree.cpp

@@ -157,7 +157,7 @@ void java_bytecode_parse_treet::methodt::output(std::ostream &out) const
 
   for(const auto &i : instructions)
   {
-    if(i.source_location.get_line()!=irep_idt())
+    if(!i.source_location.get_line().empty())
       out << "    // " << i.source_location << '\n';
 
     out << "    " << i.address << ": ";