contrib/llvm/tools/lldb/source/Plugins/Language/CPlusPlus/LibStdcppTuple.cpp

   1 //===-- LibStdcppTuple.cpp --------------------------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "LibStdcpp.h"
  11
  12 #include "lldb/Core/ValueObject.h"
  13 #include "lldb/DataFormatters/FormattersHelpers.h"
  14 #include "lldb/DataFormatters/TypeSynthetic.h"
  15 #include "lldb/Utility/ConstString.h"
  16
  17 #include <memory>
  18 #include <vector>
  19
  20 using namespace lldb;
  21 using namespace lldb_private;
  22 using namespace lldb_private::formatters;
  23
  24 namespace {
  25
  26 class LibStdcppTupleSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
  27 public:
  28   explicit LibStdcppTupleSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
  29
  30   size_t CalculateNumChildren() override;
  31
  32   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
  33
  34   bool Update() override;
  35
  36   bool MightHaveChildren() override;
  37
  38   size_t GetIndexOfChildWithName(const ConstString &name) override;
  39
  40 private:
  41   std::vector<ValueObjectSP> m_members;
  42 };
  43
  44 } // end of anonymous namespace
  45
  46 LibStdcppTupleSyntheticFrontEnd::LibStdcppTupleSyntheticFrontEnd(
  47     lldb::ValueObjectSP valobj_sp)
  48     : SyntheticChildrenFrontEnd(*valobj_sp) {
  49   Update();
  50 }
  51
  52 bool LibStdcppTupleSyntheticFrontEnd::Update() {
  53   m_members.clear();
  54
  55   ValueObjectSP valobj_backend_sp = m_backend.GetSP();
  56   if (!valobj_backend_sp)
  57     return false;
  58
  59   ValueObjectSP next_child_sp = valobj_backend_sp->GetNonSyntheticValue();
  60   while (next_child_sp != nullptr) {
  61     ValueObjectSP current_child = next_child_sp;
  62     next_child_sp = nullptr;
  63
  64     size_t child_count = current_child->GetNumChildren();
  65     for (size_t i = 0; i < child_count; ++i) {
  66       ValueObjectSP child_sp = current_child->GetChildAtIndex(i, true);
  67       llvm::StringRef name_str = child_sp->GetName().GetStringRef();
  68       if (name_str.startswith("std::_Tuple_impl<")) {
  69         next_child_sp = child_sp;
  70       } else if (name_str.startswith("std::_Head_base<")) {
  71         ValueObjectSP value_sp =
  72             child_sp->GetChildMemberWithName(ConstString("_M_head_impl"), true);
  73         if (value_sp) {
  74           StreamString name;
  75           name.Printf("[%zd]", m_members.size());
  76           m_members.push_back(value_sp->Clone(ConstString(name.GetString())));
  77         }
  78       }
  79     }
  80   }
  81
  82   return false;
  83 }
  84
  85 bool LibStdcppTupleSyntheticFrontEnd::MightHaveChildren() { return true; }
  86
  87 lldb::ValueObjectSP
  88 LibStdcppTupleSyntheticFrontEnd::GetChildAtIndex(size_t idx) {
  89   if (idx < m_members.size())
  90     return m_members[idx];
  91   return lldb::ValueObjectSP();
  92 }
  93
  94 size_t LibStdcppTupleSyntheticFrontEnd::CalculateNumChildren() {
  95   return m_members.size();
  96 }
  97
  98 size_t LibStdcppTupleSyntheticFrontEnd::GetIndexOfChildWithName(
  99     const ConstString &name) {
 100   return ExtractIndexFromString(name.GetCString());
 101 }
 102
 103 SyntheticChildrenFrontEnd *
 104 lldb_private::formatters::LibStdcppTupleSyntheticFrontEndCreator(
 105     CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
 106   return (valobj_sp ? new LibStdcppTupleSyntheticFrontEnd(valobj_sp) : nullptr);
 107 }