[lldb] Split ValueObject::CreateChildAtIndex into two functions (#94455)

The the function is doing two fairly different things, depending on how
it is called. While this allows for some code reuse, it also makes it
hard to override it correctly. Possibly for this reason
ValueObjectSynthetic overerides GetChildAtIndex instead, which forces it
to reimplement some of its functionality, most notably caching of
generated children.

Splitting this up makes it easier to move the caching to a common place
(and hopefully makes the code easier to follow in general).

14 files changed, 178 insertions, 125 deletions

diff --git a/lldb/include/lldb/Core/ValueObject.h b/lldb/include/lldb/Core/ValueObject.h
index e7e35e2..1e8c7c9 100644
--- a/lldb/include/lldb/Core/ValueObject.h
+++ b/lldb/include/lldb/Core/ValueObject.h
@@ -959,9 +959,12 @@ protected:
   /// Should only be called by ValueObject::GetChildAtIndex().
   ///
   /// \return A ValueObject managed by this ValueObject's manager.
-  virtual ValueObject *CreateChildAtIndex(size_t idx,
-                                          bool synthetic_array_member,
-                                          int32_t synthetic_index);
+  virtual ValueObject *CreateChildAtIndex(size_t idx);
+
+  /// Should only be called by ValueObject::GetSyntheticArrayMember().
+  ///
+  /// \return A ValueObject managed by this ValueObject's manager.
+  virtual ValueObject *CreateSyntheticArrayMember(size_t idx);
 
   /// Should only be called by ValueObject::GetNumChildren().
   virtual llvm::Expected<uint32_t>
diff --git a/lldb/include/lldb/Core/ValueObjectConstResult.h b/lldb/include/lldb/Core/ValueObjectConstResult.h
index 37dc086..d3b3362 100644
--- a/lldb/include/lldb/Core/ValueObjectConstResult.h
+++ b/lldb/include/lldb/Core/ValueObjectConstResult.h
@@ -79,9 +79,6 @@ public:
 
   lldb::ValueObjectSP Dereference(Status &error) override;
 
-  ValueObject *CreateChildAtIndex(size_t idx, bool synthetic_array_member,
-                                  int32_t synthetic_index) override;
-
   lldb::ValueObjectSP GetSyntheticChildAtOffset(
       uint32_t offset, const CompilerType &type, bool can_create,
       ConstString name_const_str = ConstString()) override;
@@ -151,6 +148,13 @@ private:
   ValueObjectConstResult(ExecutionContextScope *exe_scope,
                          ValueObjectManager &manager, const Status &error);
 
+  ValueObject *CreateChildAtIndex(size_t idx) override {
+    return m_impl.CreateChildAtIndex(idx);
+  }
+  ValueObject *CreateSyntheticArrayMember(size_t idx) override {
+    return m_impl.CreateSyntheticArrayMember(idx);
+  }
+
   ValueObjectConstResult(const ValueObjectConstResult &) = delete;
   const ValueObjectConstResult &
   operator=(const ValueObjectConstResult &) = delete;
diff --git a/lldb/include/lldb/Core/ValueObjectConstResultCast.h b/lldb/include/lldb/Core/ValueObjectConstResultCast.h
index efcbe0d..911a083 100644
--- a/lldb/include/lldb/Core/ValueObjectConstResultCast.h
+++ b/lldb/include/lldb/Core/ValueObjectConstResultCast.h
@@ -35,9 +35,6 @@ public:
 
   lldb::ValueObjectSP Dereference(Status &error) override;
 
-  ValueObject *CreateChildAtIndex(size_t idx, bool synthetic_array_member,
-                                  int32_t synthetic_index) override;
-
   virtual CompilerType GetCompilerType() {
     return ValueObjectCast::GetCompilerType();
   }
@@ -61,6 +58,13 @@ private:
   friend class ValueObjectConstResult;
   friend class ValueObjectConstResultImpl;
 
+  ValueObject *CreateChildAtIndex(size_t idx) override {
+    return m_impl.CreateChildAtIndex(idx);
+  }
+  ValueObject *CreateSyntheticArrayMember(size_t idx) override {
+    return m_impl.CreateSyntheticArrayMember(idx);
+  }
+
   ValueObjectConstResultCast(const ValueObjectConstResultCast &) = delete;
   const ValueObjectConstResultCast &
   operator=(const ValueObjectConstResultCast &) = delete;
diff --git a/lldb/include/lldb/Core/ValueObjectConstResultChild.h b/lldb/include/lldb/Core/ValueObjectConstResultChild.h
index 7e9da14..71a3c53 100644
--- a/lldb/include/lldb/Core/ValueObjectConstResultChild.h
+++ b/lldb/include/lldb/Core/ValueObjectConstResultChild.h
@@ -41,9 +41,6 @@ public:
 
   lldb::ValueObjectSP Dereference(Status &error) override;
 
-  ValueObject *CreateChildAtIndex(size_t idx, bool synthetic_array_member,
-                                  int32_t synthetic_index) override;
-
   virtual CompilerType GetCompilerType() {
     return ValueObjectChild::GetCompilerType();
   }
@@ -70,6 +67,13 @@ private:
   friend class ValueObjectConstResult;
   friend class ValueObjectConstResultImpl;
 
+  ValueObject *CreateChildAtIndex(size_t idx) override {
+    return m_impl.CreateChildAtIndex(idx);
+  }
+  ValueObject *CreateSyntheticArrayMember(size_t idx) override {
+    return m_impl.CreateSyntheticArrayMember(idx);
+  }
+
   ValueObjectConstResultChild(const ValueObjectConstResultChild &) = delete;
   const ValueObjectConstResultChild &
   operator=(const ValueObjectConstResultChild &) = delete;
diff --git a/lldb/include/lldb/Core/ValueObjectConstResultImpl.h b/lldb/include/lldb/Core/ValueObjectConstResultImpl.h
index 5a7a079..68ba8ae 100644
--- a/lldb/include/lldb/Core/ValueObjectConstResultImpl.h
+++ b/lldb/include/lldb/Core/ValueObjectConstResultImpl.h
@@ -38,8 +38,8 @@ public:
 
   lldb::ValueObjectSP Dereference(Status &error);
 
-  ValueObject *CreateChildAtIndex(size_t idx, bool synthetic_array_member,
-                                  int32_t synthetic_index);
+  ValueObject *CreateChildAtIndex(size_t idx);
+  ValueObject *CreateSyntheticArrayMember(size_t idx);
 
   lldb::ValueObjectSP
   GetSyntheticChildAtOffset(uint32_t offset, const CompilerType &type,
diff --git a/lldb/include/lldb/Core/ValueObjectRegister.h b/lldb/include/lldb/Core/ValueObjectRegister.h
index fec8566..d948c66 100644
--- a/lldb/include/lldb/Core/ValueObjectRegister.h
+++ b/lldb/include/lldb/Core/ValueObjectRegister.h
@@ -49,9 +49,6 @@ public:
 
   llvm::Expected<uint32_t> CalculateNumChildren(uint32_t max) override;
 
-  ValueObject *CreateChildAtIndex(size_t idx, bool synthetic_array_member,
-                                  int32_t synthetic_index) override;
-
   lldb::ValueObjectSP GetChildMemberWithName(llvm::StringRef name,
                                              bool can_create = true) override;
 
@@ -73,6 +70,11 @@ private:
                          ValueObjectManager &manager,
                          lldb::RegisterContextSP &reg_ctx_sp, uint32_t set_idx);
 
+  ValueObject *CreateChildAtIndex(size_t idx) override;
+  ValueObject *CreateSyntheticArrayMember(size_t idx) override {
+    return nullptr;
+  }
+
   // For ValueObject only
   ValueObjectRegisterSet(const ValueObjectRegisterSet &) = delete;
   const ValueObjectRegisterSet &
diff --git a/lldb/include/lldb/Core/ValueObjectVTable.h b/lldb/include/lldb/Core/ValueObjectVTable.h
index 4662f39..7087dcc 100644
--- a/lldb/include/lldb/Core/ValueObjectVTable.h
+++ b/lldb/include/lldb/Core/ValueObjectVTable.h
@@ -66,9 +66,6 @@ public:
 
   llvm::Expected<uint32_t> CalculateNumChildren(uint32_t max) override;
 
-  ValueObject *CreateChildAtIndex(size_t idx, bool synthetic_array_member,
-                                  int32_t synthetic_index) override;
-
   lldb::ValueType GetValueType() const override;
 
   ConstString GetTypeName() override;
@@ -95,6 +92,11 @@ protected:
 private:
   ValueObjectVTable(ValueObject &parent);
 
+  ValueObject *CreateChildAtIndex(size_t idx) override;
+  ValueObject *CreateSyntheticArrayMember(size_t idx) override {
+    return nullptr;
+  }
+
   // For ValueObject only
   ValueObjectVTable(const ValueObjectVTable &) = delete;
   const ValueObjectVTable &operator=(const ValueObjectVTable &) = delete;
diff --git a/lldb/source/Core/ValueObject.cpp b/lldb/source/Core/ValueObject.cpp
index c5c434a..f32cb82 100644
--- a/lldb/source/Core/ValueObject.cpp
+++ b/lldb/source/Core/ValueObject.cpp
@@ -382,7 +382,7 @@ ValueObjectSP ValueObject::GetChildAtIndex(uint32_t idx, bool can_create) {
     if (can_create && !m_children.HasChildAtIndex(idx)) {
       // No we haven't created the child at this index, so lets have our
       // subclass do it and cache the result for quick future access.
-      m_children.SetChildAtIndex(idx, CreateChildAtIndex(idx, false, 0));
+      m_children.SetChildAtIndex(idx, CreateChildAtIndex(idx));
     }
 
     ValueObject *child = m_children.GetChildAtIndex(idx);
@@ -488,14 +488,10 @@ void ValueObject::SetNumChildren(uint32_t num_children) {
   m_children.SetChildrenCount(num_children);
 }
 
-ValueObject *ValueObject::CreateChildAtIndex(size_t idx,
-                                             bool synthetic_array_member,
-                                             int32_t synthetic_index) {
-  ValueObject *valobj = nullptr;
-
+ValueObject *ValueObject::CreateChildAtIndex(size_t idx) {
   bool omit_empty_base_classes = true;
-  bool ignore_array_bounds = synthetic_array_member;
-  std::string child_name_str;
+  bool ignore_array_bounds = false;
+  std::string child_name;
   uint32_t child_byte_size = 0;
   int32_t child_byte_offset = 0;
   uint32_t child_bitfield_bit_size = 0;
@@ -503,51 +499,74 @@ ValueObject *ValueObject::CreateChildAtIndex(size_t idx,
   bool child_is_base_class = false;
   bool child_is_deref_of_parent = false;
   uint64_t language_flags = 0;
-
-  const bool transparent_pointers = !synthetic_array_member;
+  const bool transparent_pointers = true;
 
   ExecutionContext exe_ctx(GetExecutionContextRef());
 
   auto child_compiler_type_or_err =
       GetCompilerType().GetChildCompilerTypeAtIndex(
           &exe_ctx, idx, transparent_pointers, omit_empty_base_classes,
-          ignore_array_bounds, child_name_str, child_byte_size,
-          child_byte_offset, child_bitfield_bit_size, child_bitfield_bit_offset,
+          ignore_array_bounds, child_name, child_byte_size, child_byte_offset,
+          child_bitfield_bit_size, child_bitfield_bit_offset,
           child_is_base_class, child_is_deref_of_parent, this, language_flags);
-  CompilerType child_compiler_type;
-  if (!child_compiler_type_or_err)
+  if (!child_compiler_type_or_err || !child_compiler_type_or_err->IsValid()) {
     LLDB_LOG_ERROR(GetLog(LLDBLog::Types),
                    child_compiler_type_or_err.takeError(),
                    "could not find child: {0}");
-  else
-    child_compiler_type = *child_compiler_type_or_err;
+    return nullptr;
+  }
+
+  return new ValueObjectChild(
+      *this, *child_compiler_type_or_err, ConstString(child_name),
+      child_byte_size, child_byte_offset, child_bitfield_bit_size,
+      child_bitfield_bit_offset, child_is_base_class, child_is_deref_of_parent,
+      eAddressTypeInvalid, language_flags);
+}
+
+ValueObject *ValueObject::CreateSyntheticArrayMember(size_t idx) {
+  bool omit_empty_base_classes = true;
+  bool ignore_array_bounds = true;
+  std::string child_name;
+  uint32_t child_byte_size = 0;
+  int32_t child_byte_offset = 0;
+  uint32_t child_bitfield_bit_size = 0;
+  uint32_t child_bitfield_bit_offset = 0;
+  bool child_is_base_class = false;
+  bool child_is_deref_of_parent = false;
+  uint64_t language_flags = 0;
+  const bool transparent_pointers = false;
 
-  if (child_compiler_type) {
-    if (synthetic_index)
-      child_byte_offset += child_byte_size * synthetic_index;
+  ExecutionContext exe_ctx(GetExecutionContextRef());
 
-    ConstString child_name;
-    if (!child_name_str.empty())
-      child_name.SetCString(child_name_str.c_str());
+  auto child_compiler_type_or_err =
+      GetCompilerType().GetChildCompilerTypeAtIndex(
+          &exe_ctx, 0, transparent_pointers, omit_empty_base_classes,
+          ignore_array_bounds, child_name, child_byte_size, child_byte_offset,
+          child_bitfield_bit_size, child_bitfield_bit_offset,
+          child_is_base_class, child_is_deref_of_parent, this, language_flags);
+  if (!child_compiler_type_or_err) {
+    LLDB_LOG_ERROR(GetLog(LLDBLog::Types),
+                   child_compiler_type_or_err.takeError(),
+                   "could not find child: {0}");
+    return nullptr;
+  }
+
+  if (child_compiler_type_or_err->IsValid()) {
+    child_byte_offset += child_byte_size * idx;
 
-    valobj = new ValueObjectChild(
-        *this, child_compiler_type, child_name, child_byte_size,
-        child_byte_offset, child_bitfield_bit_size, child_bitfield_bit_offset,
-        child_is_base_class, child_is_deref_of_parent, eAddressTypeInvalid,
-        language_flags);
+    return new ValueObjectChild(
+        *this, *child_compiler_type_or_err, ConstString(child_name),
+        child_byte_size, child_byte_offset, child_bitfield_bit_size,
+        child_bitfield_bit_offset, child_is_base_class,
+        child_is_deref_of_parent, eAddressTypeInvalid, language_flags);
   }
 
   // In case of an incomplete type, try to use the ValueObject's
   // synthetic value to create the child ValueObject.
-  if (!valobj && synthetic_array_member) {
-    if (ValueObjectSP synth_valobj_sp = GetSyntheticValue()) {
-      valobj = synth_valobj_sp
-                   ->GetChildAtIndex(synthetic_index, synthetic_array_member)
-                   .get();
-    }
-  }
+  if (ValueObjectSP synth_valobj_sp = GetSyntheticValue())
+    return synth_valobj_sp->GetChildAtIndex(idx, /*can_create=*/true).get();
 
-  return valobj;
+  return nullptr;
 }
 
 bool ValueObject::GetSummaryAsCString(TypeSummaryImpl *summary_ptr,
@@ -1616,7 +1635,7 @@ ValueObjectSP ValueObject::GetSyntheticArrayMember(size_t index,
       ValueObject *synthetic_child;
       // We haven't made a synthetic array member for INDEX yet, so lets make
       // one and cache it for any future reference.
-      synthetic_child = CreateChildAtIndex(0, true, index);
+      synthetic_child = CreateSyntheticArrayMember(index);
 
       // Cache the value if we got one back...
       if (synthetic_child) {
diff --git a/lldb/source/Core/ValueObjectConstResult.cpp b/lldb/source/Core/ValueObjectConstResult.cpp
index 8ac2c1c..879d3c3 100644
--- a/lldb/source/Core/ValueObjectConstResult.cpp
+++ b/lldb/source/Core/ValueObjectConstResult.cpp
@@ -267,12 +267,6 @@ lldb::addr_t ValueObjectConstResult::GetAddressOf(bool scalar_is_load_address,
   return m_impl.GetAddressOf(scalar_is_load_address, address_type);
 }
 
-ValueObject *ValueObjectConstResult::CreateChildAtIndex(
-    size_t idx, bool synthetic_array_member, int32_t synthetic_index) {
-  return m_impl.CreateChildAtIndex(idx, synthetic_array_member,
-                                   synthetic_index);
-}
-
 size_t ValueObjectConstResult::GetPointeeData(DataExtractor &data,
                                               uint32_t item_idx,
                                               uint32_t item_count) {
diff --git a/lldb/source/Core/ValueObjectConstResultCast.cpp b/lldb/source/Core/ValueObjectConstResultCast.cpp
index fceb263..bf7a12d 100644
--- a/lldb/source/Core/ValueObjectConstResultCast.cpp
+++ b/lldb/source/Core/ValueObjectConstResultCast.cpp
@@ -44,12 +44,6 @@ lldb::ValueObjectSP ValueObjectConstResultCast::AddressOf(Status &error) {
   return m_impl.AddressOf(error);
 }
 
-ValueObject *ValueObjectConstResultCast::CreateChildAtIndex(
-    size_t idx, bool synthetic_array_member, int32_t synthetic_index) {
-  return m_impl.CreateChildAtIndex(idx, synthetic_array_member,
-                                   synthetic_index);
-}
-
 size_t ValueObjectConstResultCast::GetPointeeData(DataExtractor &data,
                                                   uint32_t item_idx,
                                                   uint32_t item_count) {
diff --git a/lldb/source/Core/ValueObjectConstResultChild.cpp b/lldb/source/Core/ValueObjectConstResultChild.cpp
index 36bf11a..39fc0c9 100644
--- a/lldb/source/Core/ValueObjectConstResultChild.cpp
+++ b/lldb/source/Core/ValueObjectConstResultChild.cpp
@@ -56,12 +56,6 @@ lldb::addr_t ValueObjectConstResultChild::GetAddressOf(
   return m_impl.GetAddressOf(scalar_is_load_address, address_type);
 }
 
-ValueObject *ValueObjectConstResultChild::CreateChildAtIndex(
-    size_t idx, bool synthetic_array_member, int32_t synthetic_index) {
-  return m_impl.CreateChildAtIndex(idx, synthetic_array_member,
-                                   synthetic_index);
-}
-
 size_t ValueObjectConstResultChild::GetPointeeData(DataExtractor &data,
                                                    uint32_t item_idx,
                                                    uint32_t item_count) {
diff --git a/lldb/source/Core/ValueObjectConstResultImpl.cpp b/lldb/source/Core/ValueObjectConstResultImpl.cpp
index 493980d..2a7c907 100644
--- a/lldb/source/Core/ValueObjectConstResultImpl.cpp
+++ b/lldb/source/Core/ValueObjectConstResultImpl.cpp
@@ -46,18 +46,15 @@ lldb::ValueObjectSP ValueObjectConstResultImpl::Dereference(Status &error) {
   return m_impl_backend->ValueObject::Dereference(error);
 }
 
-ValueObject *ValueObjectConstResultImpl::CreateChildAtIndex(
-    size_t idx, bool synthetic_array_member, int32_t synthetic_index) {
+ValueObject *ValueObjectConstResultImpl::CreateChildAtIndex(size_t idx) {
   if (m_impl_backend == nullptr)
     return nullptr;
 
   m_impl_backend->UpdateValueIfNeeded(false);
 
-  ValueObjectConstResultChild *valobj = nullptr;
-
   bool omit_empty_base_classes = true;
-  bool ignore_array_bounds = synthetic_array_member;
-  std::string child_name_str;
+  bool ignore_array_bounds = false;
+  std::string child_name;
   uint32_t child_byte_size = 0;
   int32_t child_byte_offset = 0;
   uint32_t child_bitfield_bit_size = 0;
@@ -65,56 +62,100 @@ ValueObject *ValueObjectConstResultImpl::CreateChildAtIndex(
   bool child_is_base_class = false;
   bool child_is_deref_of_parent = false;
   uint64_t language_flags;
-
-  const bool transparent_pointers = !synthetic_array_member;
+  const bool transparent_pointers = true;
   CompilerType compiler_type = m_impl_backend->GetCompilerType();
 
   ExecutionContext exe_ctx(m_impl_backend->GetExecutionContextRef());
 
   auto child_compiler_type_or_err = compiler_type.GetChildCompilerTypeAtIndex(
       &exe_ctx, idx, transparent_pointers, omit_empty_base_classes,
-      ignore_array_bounds, child_name_str, child_byte_size, child_byte_offset,
+      ignore_array_bounds, child_name, child_byte_size, child_byte_offset,
       child_bitfield_bit_size, child_bitfield_bit_offset, child_is_base_class,
       child_is_deref_of_parent, m_impl_backend, language_flags);
-  CompilerType child_compiler_type;
-  if (!child_compiler_type_or_err)
+
+  // One might think we should check that the size of the children
+  // is always strictly positive, hence we could avoid creating a
+  // ValueObject if that's not the case, but it turns out there
+  // are languages out there which allow zero-size types with
+  // children (e.g. Swift).
+  if (!child_compiler_type_or_err || !child_compiler_type_or_err->IsValid()) {
     LLDB_LOG_ERROR(GetLog(LLDBLog::Types),
                    child_compiler_type_or_err.takeError(),
                    "could not find child: {0}");
-  else
-    child_compiler_type = *child_compiler_type_or_err;
+    return nullptr;
+  }
 
+  lldb::addr_t child_live_addr = LLDB_INVALID_ADDRESS;
+  // Transfer the live address (with offset) to the child.  But if
+  // the parent is a pointer, the live address is where that pointer
+  // value lives in memory, so the children live addresses aren't
+  // offsets from that value, they are just other load addresses that
+  // are recorded in the Value of the child ValueObjects.
+  if (m_live_address != LLDB_INVALID_ADDRESS && !compiler_type.IsPointerType())
+    child_live_addr = m_live_address + child_byte_offset;
+
+  return new ValueObjectConstResultChild(
+      *m_impl_backend, *child_compiler_type_or_err, ConstString(child_name),
+      child_byte_size, child_byte_offset, child_bitfield_bit_size,
+      child_bitfield_bit_offset, child_is_base_class, child_is_deref_of_parent,
+      child_live_addr, language_flags);
+}
+
+ValueObject *
+ValueObjectConstResultImpl::CreateSyntheticArrayMember(size_t idx) {
+  if (m_impl_backend == nullptr)
+    return nullptr;
+
+  m_impl_backend->UpdateValueIfNeeded(false);
+
+  bool omit_empty_base_classes = true;
+  bool ignore_array_bounds = true;
+  std::string child_name;
+  uint32_t child_byte_size = 0;
+  int32_t child_byte_offset = 0;
+  uint32_t child_bitfield_bit_size = 0;
+  uint32_t child_bitfield_bit_offset = 0;
+  bool child_is_base_class = false;
+  bool child_is_deref_of_parent = false;
+  uint64_t language_flags;
+
+  const bool transparent_pointers = false;
+  CompilerType compiler_type = m_impl_backend->GetCompilerType();
+
+  ExecutionContext exe_ctx(m_impl_backend->GetExecutionContextRef());
+
+  auto child_compiler_type_or_err = compiler_type.GetChildCompilerTypeAtIndex(
+      &exe_ctx, 0, transparent_pointers, omit_empty_base_classes,
+      ignore_array_bounds, child_name, child_byte_size, child_byte_offset,
+      child_bitfield_bit_size, child_bitfield_bit_offset, child_is_base_class,
+      child_is_deref_of_parent, m_impl_backend, language_flags);
   // One might think we should check that the size of the children
   // is always strictly positive, hence we could avoid creating a
   // ValueObject if that's not the case, but it turns out there
   // are languages out there which allow zero-size types with
   // children (e.g. Swift).
-  if (child_compiler_type) {
-    if (synthetic_index)
-      child_byte_offset += child_byte_size * synthetic_index;
-
-    ConstString child_name;
-    if (!child_name_str.empty())
-      child_name.SetCString(child_name_str.c_str());
-
-    lldb::addr_t child_live_addr = LLDB_INVALID_ADDRESS;
-    // Transfer the live address (with offset) to the child.  But if
-    // the parent is a pointer, the live address is where that pointer
-    // value lives in memory, so the children live addresses aren't
-    // offsets from that value, they are just other load addresses that
-    // are recorded in the Value of the child ValueObjects.
-    if (m_live_address != LLDB_INVALID_ADDRESS) {
-      if (!compiler_type.IsPointerType())
-        child_live_addr = m_live_address + child_byte_offset;
-    }
-    valobj = new ValueObjectConstResultChild(
-        *m_impl_backend, child_compiler_type, child_name, child_byte_size,
-        child_byte_offset, child_bitfield_bit_size, child_bitfield_bit_offset,
-        child_is_base_class, child_is_deref_of_parent, child_live_addr,
-        language_flags);
+  if (!child_compiler_type_or_err || !child_compiler_type_or_err->IsValid()) {
+    LLDB_LOG_ERROR(GetLog(LLDBLog::Types),
+                   child_compiler_type_or_err.takeError(),
+                   "could not find child: {0}");
+    return nullptr;
   }
 
-  return valobj;
+  child_byte_offset += child_byte_size * idx;
+
+  lldb::addr_t child_live_addr = LLDB_INVALID_ADDRESS;
+  // Transfer the live address (with offset) to the child.  But if
+  // the parent is a pointer, the live address is where that pointer
+  // value lives in memory, so the children live addresses aren't
+  // offsets from that value, they are just other load addresses that
+  // are recorded in the Value of the child ValueObjects.
+  if (m_live_address != LLDB_INVALID_ADDRESS && !compiler_type.IsPointerType())
+    child_live_addr = m_live_address + child_byte_offset;
+  return new ValueObjectConstResultChild(
+      *m_impl_backend, *child_compiler_type_or_err, ConstString(child_name),
+      child_byte_size, child_byte_offset, child_bitfield_bit_size,
+      child_bitfield_bit_offset, child_is_base_class, child_is_deref_of_parent,
+      child_live_addr, language_flags);
 }
 
 lldb::ValueObjectSP ValueObjectConstResultImpl::GetSyntheticChildAtOffset(
diff --git a/lldb/source/Core/ValueObjectRegister.cpp b/lldb/source/Core/ValueObjectRegister.cpp
index 9d9da8b..8b5557a 100644
--- a/lldb/source/Core/ValueObjectRegister.cpp
+++ b/lldb/source/Core/ValueObjectRegister.cpp
@@ -115,17 +115,13 @@ bool ValueObjectRegisterSet::UpdateValue() {
   return m_error.Success();
 }
 
-ValueObject *ValueObjectRegisterSet::CreateChildAtIndex(
-    size_t idx, bool synthetic_array_member, int32_t synthetic_index) {
-  ValueObject *valobj = nullptr;
+ValueObject *ValueObjectRegisterSet::CreateChildAtIndex(size_t idx) {
   if (m_reg_ctx_sp && m_reg_set) {
-    uint32_t num_children = GetNumChildrenIgnoringErrors();
-    if (idx < num_children)
-      valobj = new ValueObjectRegister(
-          *this, m_reg_ctx_sp,
-          m_reg_ctx_sp->GetRegisterInfoAtIndex(m_reg_set->registers[idx]));
+    return new ValueObjectRegister(
+        *this, m_reg_ctx_sp,
+        m_reg_ctx_sp->GetRegisterInfoAtIndex(m_reg_set->registers[idx]));
   }
-  return valobj;
+  return nullptr;
 }
 
 lldb::ValueObjectSP
diff --git a/lldb/source/Core/ValueObjectVTable.cpp b/lldb/source/Core/ValueObjectVTable.cpp
index 9bfe8dc..72e198d 100644
--- a/lldb/source/Core/ValueObjectVTable.cpp
+++ b/lldb/source/Core/ValueObjectVTable.cpp
@@ -185,11 +185,7 @@ ConstString ValueObjectVTable::GetDisplayTypeName() {
 
 bool ValueObjectVTable::IsInScope() { return GetParent()->IsInScope(); }
 
-ValueObject *ValueObjectVTable::CreateChildAtIndex(size_t idx,
-                                                   bool synthetic_array_member,
-                                                   int32_t synthetic_index) {
-  if (synthetic_array_member)
-    return nullptr;
+ValueObject *ValueObjectVTable::CreateChildAtIndex(size_t idx) {
   return new ValueObjectVTableChild(*this, idx, m_addr_size);
 }