1 //===-- LibCxxUnorderedMap.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 // C Includes
11 // C++ Includes
12 // Other libraries and framework includes
13 // Project includes
14 #include "LibCxx.h"
15 
16 #include "lldb/Core/DataBufferHeap.h"
17 #include "lldb/Core/Error.h"
18 #include "lldb/Core/Stream.h"
19 #include "lldb/Core/ValueObject.h"
20 #include "lldb/Core/ValueObjectConstResult.h"
21 #include "lldb/DataFormatters/FormattersHelpers.h"
22 #include "lldb/Host/Endian.h"
23 #include "lldb/Symbol/ClangASTContext.h"
24 #include "lldb/Target/Target.h"
25 
26 using namespace lldb;
27 using namespace lldb_private;
28 using namespace lldb_private::formatters;
29 
30 namespace lldb_private {
31     namespace formatters {
32         class LibcxxStdUnorderedMapSyntheticFrontEnd : public SyntheticChildrenFrontEnd
33         {
34         public:
35             LibcxxStdUnorderedMapSyntheticFrontEnd (lldb::ValueObjectSP valobj_sp);
36 
37             ~LibcxxStdUnorderedMapSyntheticFrontEnd() override = default;
38 
39             size_t
40             CalculateNumChildren() override;
41 
42             lldb::ValueObjectSP
43             GetChildAtIndex(size_t idx) override;
44 
45             bool
46             Update() override;
47 
48             bool
49             MightHaveChildren() override;
50 
51             size_t
52             GetIndexOfChildWithName(const ConstString &name) override;
53 
54         private:
55             ValueObject* m_tree;
56             size_t m_num_elements;
57             ValueObject* m_next_element;
58             std::vector<std::pair<ValueObject*, uint64_t> > m_elements_cache;
59         };
60     } // namespace formatters
61 } // namespace lldb_private
62 
63 lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::LibcxxStdUnorderedMapSyntheticFrontEnd (lldb::ValueObjectSP valobj_sp) :
64     SyntheticChildrenFrontEnd(*valobj_sp),
65     m_tree(nullptr),
66     m_num_elements(0),
67     m_next_element(nullptr),
68     m_elements_cache()
69 {
70     if (valobj_sp)
71         Update();
72 }
73 
74 size_t
75 lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::CalculateNumChildren ()
76 {
77     if (m_num_elements != UINT32_MAX)
78         return m_num_elements;
79     return 0;
80 }
81 
82 lldb::ValueObjectSP
83 lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::GetChildAtIndex (size_t idx)
84 {
85     if (idx >= CalculateNumChildren())
86         return lldb::ValueObjectSP();
87     if (m_tree == nullptr)
88         return lldb::ValueObjectSP();
89 
90     while (idx >= m_elements_cache.size())
91     {
92         if (m_next_element == nullptr)
93             return lldb::ValueObjectSP();
94 
95         Error error;
96         ValueObjectSP node_sp = m_next_element->Dereference(error);
97         if (!node_sp || error.Fail())
98             return lldb::ValueObjectSP();
99 
100         ValueObjectSP value_sp = node_sp->GetChildMemberWithName(ConstString("__value_"), true);
101         ValueObjectSP hash_sp = node_sp->GetChildMemberWithName(ConstString("__hash_"), true);
102         if (!hash_sp || !value_sp)
103             return lldb::ValueObjectSP();
104         m_elements_cache.push_back({value_sp.get(),hash_sp->GetValueAsUnsigned(0)});
105         m_next_element = node_sp->GetChildMemberWithName(ConstString("__next_"),true).get();
106         if (!m_next_element || m_next_element->GetValueAsUnsigned(0) == 0)
107             m_next_element = nullptr;
108     }
109 
110     std::pair<ValueObject*, uint64_t> val_hash = m_elements_cache[idx];
111     if (!val_hash.first)
112         return lldb::ValueObjectSP();
113     StreamString stream;
114     stream.Printf("[%" PRIu64 "]", (uint64_t)idx);
115     DataExtractor data;
116     Error error;
117     val_hash.first->GetData(data, error);
118     if (error.Fail())
119         return lldb::ValueObjectSP();
120     const bool thread_and_frame_only_if_stopped = true;
121     ExecutionContext exe_ctx = val_hash.first->GetExecutionContextRef().Lock(thread_and_frame_only_if_stopped);
122     return CreateValueObjectFromData(stream.GetData(),
123                                      data,
124                                      exe_ctx,
125                                      val_hash.first->GetCompilerType());
126 }
127 
128 bool
129 lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::Update()
130 {
131     m_num_elements = UINT32_MAX;
132     m_next_element = nullptr;
133     m_elements_cache.clear();
134     ValueObjectSP table_sp = m_backend.GetChildMemberWithName(ConstString("__table_"), true);
135     if (!table_sp)
136         return false;
137     ValueObjectSP num_elements_sp = table_sp->GetChildAtNamePath({ConstString("__p2_"),ConstString("__first_")});
138     if (!num_elements_sp)
139         return false;
140     m_num_elements = num_elements_sp->GetValueAsUnsigned(0);
141     m_tree = table_sp->GetChildAtNamePath({ConstString("__p1_"),ConstString("__first_"),ConstString("__next_")}).get();
142     if (m_num_elements > 0)
143         m_next_element = table_sp->GetChildAtNamePath({ConstString("__p1_"),ConstString("__first_"),ConstString("__next_")}).get();
144     return false;
145 }
146 
147 bool
148 lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::MightHaveChildren ()
149 {
150     return true;
151 }
152 
153 size_t
154 lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::GetIndexOfChildWithName (const ConstString &name)
155 {
156     return ExtractIndexFromString(name.GetCString());
157 }
158 
159 SyntheticChildrenFrontEnd*
160 lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEndCreator (CXXSyntheticChildren*, lldb::ValueObjectSP valobj_sp)
161 {
162     return (valobj_sp ? new LibcxxStdUnorderedMapSyntheticFrontEnd(valobj_sp) : nullptr);
163 }
164