contrib/llvm/tools/lldb/source/DataFormatters/LibCxxVector.cpp

   1 //===-- LibCxxVector.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 "lldb/DataFormatters/CXXFormatterFunctions.h"
  11
  12 #include "lldb/Core/ConstString.h"
  13 #include "lldb/Core/ValueObject.h"
  14
  15 using namespace lldb;
  16 using namespace lldb_private;
  17 using namespace lldb_private::formatters;
  18
  19 namespace lldb_private {
  20     namespace formatters {
  21         class LibcxxStdVectorSyntheticFrontEnd : public SyntheticChildrenFrontEnd
  22         {
  23         public:
  24             LibcxxStdVectorSyntheticFrontEnd (lldb::ValueObjectSP valobj_sp);
  25
  26             virtual size_t
  27             CalculateNumChildren ();
  28
  29             virtual lldb::ValueObjectSP
  30             GetChildAtIndex (size_t idx);
  31
  32             virtual bool
  33             Update();
  34
  35             virtual bool
  36             MightHaveChildren ();
  37
  38             virtual size_t
  39             GetIndexOfChildWithName (const ConstString &name);
  40
  41             virtual
  42             ~LibcxxStdVectorSyntheticFrontEnd ();
  43         private:
  44             ValueObject* m_start;
  45             ValueObject* m_finish;
  46             ClangASTType m_element_type;
  47             uint32_t m_element_size;
  48             std::map<size_t,lldb::ValueObjectSP> m_children;
  49         };
  50     }
  51 }
  52
  53 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::LibcxxStdVectorSyntheticFrontEnd (lldb::ValueObjectSP valobj_sp) :
  54 SyntheticChildrenFrontEnd(*valobj_sp.get()),
  55 m_start(NULL),
  56 m_finish(NULL),
  57 m_element_type(),
  58 m_element_size(0),
  59 m_children()
  60 {
  61     if (valobj_sp)
  62         Update();
  63 }
  64
  65 size_t
  66 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::CalculateNumChildren ()
  67 {
  68     if (!m_start || !m_finish)
  69         return 0;
  70     uint64_t start_val = m_start->GetValueAsUnsigned(0);
  71     uint64_t finish_val = m_finish->GetValueAsUnsigned(0);
  72
  73     if (start_val == 0 || finish_val == 0)
  74         return 0;
  75
  76     if (start_val >= finish_val)
  77         return 0;
  78
  79     size_t num_children = (finish_val - start_val);
  80     if (num_children % m_element_size)
  81         return 0;
  82     return num_children/m_element_size;
  83 }
  84
  85 lldb::ValueObjectSP
  86 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::GetChildAtIndex (size_t idx)
  87 {
  88     if (!m_start || !m_finish)
  89         return lldb::ValueObjectSP();
  90
  91     auto cached = m_children.find(idx);
  92     if (cached != m_children.end())
  93         return cached->second;
  94
  95     uint64_t offset = idx * m_element_size;
  96     offset = offset + m_start->GetValueAsUnsigned(0);
  97     StreamString name;
  98     name.Printf("[%" PRIu64 "]", (uint64_t)idx);
  99     ValueObjectSP child_sp = CreateValueObjectFromAddress(name.GetData(), offset, m_backend.GetExecutionContextRef(), m_element_type);
 100     m_children[idx] = child_sp;
 101     return child_sp;
 102 }
 103
 104 bool
 105 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::Update()
 106 {
 107     m_start = m_finish = NULL;
 108     m_children.clear();
 109     ValueObjectSP data_type_finder_sp(m_backend.GetChildMemberWithName(ConstString("__end_cap_"),true));
 110     if (!data_type_finder_sp)
 111         return false;
 112     data_type_finder_sp = data_type_finder_sp->GetChildMemberWithName(ConstString("__first_"),true);
 113     if (!data_type_finder_sp)
 114         return false;
 115     m_element_type = data_type_finder_sp->GetClangType().GetPointeeType();
 116     m_element_size = m_element_type.GetByteSize(nullptr);
 117
 118     if (m_element_size > 0)
 119     {
 120         // store raw pointers or end up with a circular dependency
 121         m_start = m_backend.GetChildMemberWithName(ConstString("__begin_"),true).get();
 122         m_finish = m_backend.GetChildMemberWithName(ConstString("__end_"),true).get();
 123     }
 124     return false;
 125 }
 126
 127 bool
 128 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::MightHaveChildren ()
 129 {
 130     return true;
 131 }
 132
 133 size_t
 134 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::GetIndexOfChildWithName (const ConstString &name)
 135 {
 136     if (!m_start || !m_finish)
 137         return UINT32_MAX;
 138     return ExtractIndexFromString(name.GetCString());
 139 }
 140
 141 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::~LibcxxStdVectorSyntheticFrontEnd ()
 142 {
 143     // these need to stay around because they are child objects who will follow their parent's life cycle
 144     // delete m_start;
 145     // delete m_finish;
 146 }
 147
 148 lldb_private::SyntheticChildrenFrontEnd*
 149 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEndCreator (CXXSyntheticChildren*, lldb::ValueObjectSP valobj_sp)
 150 {
 151     if (!valobj_sp)
 152         return NULL;
 153     return (new LibcxxStdVectorSyntheticFrontEnd(valobj_sp));
 154 }
 155