Stop calling ValueObject::SetName from synthetic child providers

Summary:
Calling ValueObject::SetName from a sythetic child provider would change
the underying value object used for the non-synthetic child as well what
is clearly unintentional.

Reviewers: jingham, labath

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D31371

llvm-svn: 299259

lldb/include/lldb/Core/ValueObject.h

@@ -553,6 +553,9 @@ public:
 
   lldb::ValueObjectSP GetSP() { return m_manager->GetSharedPointer(this); }
 
+  // Change the name of the current ValueObject. Should *not* be used from a
+  // synthetic child provider as it would change the name of the non synthetic
+  // child as well.
   void SetName(const ConstString &name);
 
   virtual lldb::addr_t GetAddressOf(bool scalar_is_load_address = true,
@@ -601,6 +604,12 @@ public:
 
   virtual lldb::ValueObjectSP Dereference(Error &error);
 
+  // Creates a copy of the ValueObject with a new name and setting the current
+  // ValueObject as its parent. It should be used when we want to change the
+  // name of a ValueObject without modifying the actual ValueObject itself
+  // (e.g. sythetic child provider).
+  virtual lldb::ValueObjectSP Clone(const ConstString &new_name);
+
   virtual lldb::ValueObjectSP AddressOf(Error &error);
 
   virtual lldb::addr_t GetLiveAddress() { return LLDB_INVALID_ADDRESS; }

lldb/source/Core/ValueObject.cpp

@@ -2962,6 +2962,10 @@ ValueObjectSP ValueObject::Cast(const CompilerType &compiler_type) {
   return ValueObjectCast::Create(*this, GetName(), compiler_type);
 }
 
+lldb::ValueObjectSP ValueObject::Clone(const ConstString &new_name) {
+  return ValueObjectCast::Create(*this, new_name, GetCompilerType());
+}
+
 ValueObjectSP ValueObject::CastPointerType(const char *name,
                                            CompilerType &compiler_type) {
   ValueObjectSP valobj_sp;

lldb/source/DataFormatters/VectorType.cpp

@@ -204,14 +204,12 @@ public:
     if (idx >= CalculateNumChildren())
       return lldb::ValueObjectSP();
     auto offset = idx * m_child_type.GetByteSize(nullptr);
-    ValueObjectSP child_sp(
-        m_backend.GetSyntheticChildAtOffset(offset, m_child_type, true));
-    if (!child_sp)
-      return child_sp;
-
     StreamString idx_name;
     idx_name.Printf("[%" PRIu64 "]", (uint64_t)idx);
-    child_sp->SetName(ConstString(idx_name.GetString()));
+    ValueObjectSP child_sp(m_backend.GetSyntheticChildAtOffset(
+        offset, m_child_type, true, ConstString(idx_name.GetString())));
+    if (!child_sp)
+      return child_sp;
 
     child_sp->SetFormat(m_item_format);
 

lldb/source/Plugins/Language/CPlusPlus/LibCxxMap.cpp

@@ -406,7 +406,7 @@ lldb_private::formatters::LibcxxStdMapSyntheticFrontEnd::GetChildAtIndex(
     case 1: {
       auto child0_sp = potential_child_sp->GetChildAtIndex(0, true);
       if (child0_sp && child0_sp->GetName() == g___cc)
-        potential_child_sp = child0_sp;
+        potential_child_sp = child0_sp->Clone(ConstString(name.GetString()));
       break;
     }
     case 2: {
@@ -414,11 +414,10 @@ lldb_private::formatters::LibcxxStdMapSyntheticFrontEnd::GetChildAtIndex(
       auto child1_sp = potential_child_sp->GetChildAtIndex(1, true);
       if (child0_sp && child0_sp->GetName() == g___cc && child1_sp &&
           child1_sp->GetName() == g___nc)
-        potential_child_sp = child0_sp;
+        potential_child_sp = child0_sp->Clone(ConstString(name.GetString()));
       break;
     }
     }
-    potential_child_sp->SetName(ConstString(name.GetString()));
   }
   m_iterators[idx] = iterator;
   return potential_child_sp;

lldb/source/Plugins/Language/CPlusPlus/LibStdcppTuple.cpp

@@ -73,9 +73,7 @@ bool LibStdcppTupleSyntheticFrontEnd::Update() {
         if (value_sp) {
           StreamString name;
           name.Printf("[%zd]", m_members.size());
-          value_sp->SetName(ConstString(name.GetString()));
-
-          m_members.push_back(value_sp);
+          m_members.push_back(value_sp->Clone(ConstString(name.GetString())));
         }
       }
     }

lldb/source/Plugins/Language/CPlusPlus/LibStdcppUniquePointer.cpp

@@ -70,19 +70,19 @@ bool LibStdcppUniquePtrSyntheticFrontEnd::Update() {
   std::unique_ptr<SyntheticChildrenFrontEnd> tuple_frontend(
       LibStdcppTupleSyntheticFrontEndCreator(nullptr, tuple_sp));
 
-  m_ptr_obj = tuple_frontend->GetChildAtIndex(0);
-  if (m_ptr_obj)
-    m_ptr_obj->SetName(ConstString("pointer"));
+  ValueObjectSP ptr_obj = tuple_frontend->GetChildAtIndex(0);
+  if (ptr_obj)
+    m_ptr_obj = ptr_obj->Clone(ConstString("pointer"));
 
-  m_del_obj = tuple_frontend->GetChildAtIndex(1);
-  if (m_del_obj)
-    m_del_obj->SetName(ConstString("deleter"));
+  ValueObjectSP del_obj = tuple_frontend->GetChildAtIndex(1);
+  if (del_obj)
+    m_del_obj = del_obj->Clone(ConstString("deleter"));
 
   if (m_ptr_obj) {
     Error error;
-    m_obj_obj = m_ptr_obj->Dereference(error);
+    ValueObjectSP obj_obj = m_ptr_obj->Dereference(error);
     if (error.Success()) {
-      m_obj_obj->SetName(ConstString("object"));
+      m_obj_obj = obj_obj->Clone(ConstString("object"));
     }
   }