1 files changed, 119 insertions, 0 deletions
diff --git a/contrib/llvm-project/lldb/source/Plugins/Language/CPlusPlus/LibCxxInitializerList.cpp b/contrib/llvm-project/lldb/source/Plugins/Language/CPlusPlus/LibCxxInitializerList.cpp
new file mode 100644
index 000000000000..bd9c72497664
--- /dev/null
+++ b/contrib/llvm-project/lldb/source/Plugins/Language/CPlusPlus/LibCxxInitializerList.cpp
@@ -0,0 +1,119 @@
+//===-- LibCxxInitializerList.cpp -----------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "LibCxx.h"
+
+#include "lldb/Core/ValueObject.h"
+#include "lldb/DataFormatters/FormattersHelpers.h"
+#include "lldb/Utility/ConstString.h"
+#include <optional>
+
+using namespace lldb;
+using namespace lldb_private;
+using namespace lldb_private::formatters;
+
+namespace lldb_private {
+namespace formatters {
+class LibcxxInitializerListSyntheticFrontEnd
+    : public SyntheticChildrenFrontEnd {
+public:
+  LibcxxInitializerListSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
+
+  ~LibcxxInitializerListSyntheticFrontEnd() override;
+
+  llvm::Expected<uint32_t> CalculateNumChildren() override;
+
+  lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override;
+
+  lldb::ChildCacheState Update() override;
+
+  bool MightHaveChildren() override;
+
+  size_t GetIndexOfChildWithName(ConstString name) override;
+
+private:
+  ValueObject *m_start = nullptr;
+  CompilerType m_element_type;
+  uint32_t m_element_size = 0;
+  size_t m_num_elements = 0;
+};
+} // namespace formatters
+} // namespace lldb_private
+
+lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
+    LibcxxInitializerListSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
+    : SyntheticChildrenFrontEnd(*valobj_sp), m_element_type() {
+  if (valobj_sp)
+    Update();
+}
+
+lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
+    ~LibcxxInitializerListSyntheticFrontEnd() {
+  // this needs to stay around because it's a child object who will follow its
+  // parent's life cycle
+  // delete m_start;
+}
+
+llvm::Expected<uint32_t> lldb_private::formatters::
+    LibcxxInitializerListSyntheticFrontEnd::CalculateNumChildren() {
+  m_num_elements = 0;
+  ValueObjectSP size_sp(m_backend.GetChildMemberWithName("__size_"));
+  if (size_sp)
+    m_num_elements = size_sp->GetValueAsUnsigned(0);
+  return m_num_elements;
+}
+
+lldb::ValueObjectSP lldb_private::formatters::
+    LibcxxInitializerListSyntheticFrontEnd::GetChildAtIndex(uint32_t idx) {
+  if (!m_start)
+    return lldb::ValueObjectSP();
+
+  uint64_t offset = idx * m_element_size;
+  offset = offset + m_start->GetValueAsUnsigned(0);
+  StreamString name;
+  name.Printf("[%" PRIu64 "]", (uint64_t)idx);
+  return CreateValueObjectFromAddress(name.GetString(), offset,
+                                      m_backend.GetExecutionContextRef(),
+                                      m_element_type);
+}
+
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::Update() {
+  m_start = nullptr;
+  m_num_elements = 0;
+  m_element_type = m_backend.GetCompilerType().GetTypeTemplateArgument(0);
+  if (!m_element_type.IsValid())
+    return lldb::ChildCacheState::eRefetch;
+
+  if (std::optional<uint64_t> size = m_element_type.GetByteSize(nullptr)) {
+    m_element_size = *size;
+    // Store raw pointers or end up with a circular dependency.
+    m_start = m_backend.GetChildMemberWithName("__begin_").get();
+  }
+
+  return lldb::ChildCacheState::eRefetch;
+}
+
+bool lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
+    MightHaveChildren() {
+  return true;
+}
+
+size_t lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
+    GetIndexOfChildWithName(ConstString name) {
+  if (!m_start)
+    return UINT32_MAX;
+  return ExtractIndexFromString(name.GetCString());
+}
+
+lldb_private::SyntheticChildrenFrontEnd *
+lldb_private::formatters::LibcxxInitializerListSyntheticFrontEndCreator(
+    CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
+  return (valobj_sp ? new LibcxxInitializerListSyntheticFrontEnd(valobj_sp)
+                    : nullptr);
+}