1 //===-- LibCxxVector.cpp --------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "LibCxx.h"
10
11 #include "lldb/Core/ValueObject.h"
12 #include "lldb/DataFormatters/FormattersHelpers.h"
13 #include "lldb/Utility/ConstString.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 public:
23 LibcxxStdVectorSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
24
25 ~LibcxxStdVectorSyntheticFrontEnd() override;
26
27 size_t CalculateNumChildren() override;
28
29 lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
30
31 bool Update() override;
32
33 bool MightHaveChildren() override;
34
35 size_t GetIndexOfChildWithName(ConstString name) override;
36
37 private:
38 ValueObject *m_start = nullptr;
39 ValueObject *m_finish = nullptr;
40 CompilerType m_element_type;
41 uint32_t m_element_size = 0;
42 };
43
44 class LibcxxVectorBoolSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
45 public:
46 LibcxxVectorBoolSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp);
47
48 size_t CalculateNumChildren() override;
49
50 lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
51
52 bool Update() override;
53
MightHaveChildren()54 bool MightHaveChildren() override { return true; }
55
56 size_t GetIndexOfChildWithName(ConstString name) override;
57
58 private:
59 CompilerType m_bool_type;
60 ExecutionContextRef m_exe_ctx_ref;
61 uint64_t m_count = 0;
62 lldb::addr_t m_base_data_address = 0;
63 std::map<size_t, lldb::ValueObjectSP> m_children;
64 };
65
66 } // namespace formatters
67 } // namespace lldb_private
68
69 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::
LibcxxStdVectorSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)70 LibcxxStdVectorSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
71 : SyntheticChildrenFrontEnd(*valobj_sp), m_element_type() {
72 if (valobj_sp)
73 Update();
74 }
75
76 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::
~LibcxxStdVectorSyntheticFrontEnd()77 ~LibcxxStdVectorSyntheticFrontEnd() {
78 // these need to stay around because they are child objects who will follow
79 // their parent's life cycle
80 // delete m_start;
81 // delete m_finish;
82 }
83
84 size_t lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::
CalculateNumChildren()85 CalculateNumChildren() {
86 if (!m_start || !m_finish)
87 return 0;
88 uint64_t start_val = m_start->GetValueAsUnsigned(0);
89 uint64_t finish_val = m_finish->GetValueAsUnsigned(0);
90
91 if (start_val == 0 || finish_val == 0)
92 return 0;
93
94 if (start_val >= finish_val)
95 return 0;
96
97 size_t num_children = (finish_val - start_val);
98 if (num_children % m_element_size)
99 return 0;
100 return num_children / m_element_size;
101 }
102
103 lldb::ValueObjectSP
GetChildAtIndex(size_t idx)104 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::GetChildAtIndex(
105 size_t idx) {
106 if (!m_start || !m_finish)
107 return lldb::ValueObjectSP();
108
109 uint64_t offset = idx * m_element_size;
110 offset = offset + m_start->GetValueAsUnsigned(0);
111 StreamString name;
112 name.Printf("[%" PRIu64 "]", (uint64_t)idx);
113 return CreateValueObjectFromAddress(name.GetString(), offset,
114 m_backend.GetExecutionContextRef(),
115 m_element_type);
116 }
117
Update()118 bool lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::Update() {
119 m_start = m_finish = nullptr;
120 ValueObjectSP data_type_finder_sp(
121 m_backend.GetChildMemberWithName(ConstString("__end_cap_"), true));
122 if (!data_type_finder_sp)
123 return false;
124
125 switch (data_type_finder_sp->GetCompilerType().GetNumDirectBaseClasses()) {
126 case 1:
127 // Assume a pre llvm r300140 __compressed_pair implementation:
128 data_type_finder_sp = data_type_finder_sp->GetChildMemberWithName(
129 ConstString("__first_"), true);
130 break;
131 case 2: {
132 // Assume a post llvm r300140 __compressed_pair implementation:
133 ValueObjectSP first_elem_parent_sp =
134 data_type_finder_sp->GetChildAtIndex(0, true);
135 data_type_finder_sp = first_elem_parent_sp->GetChildMemberWithName(
136 ConstString("__value_"), true);
137 break;
138 }
139 default:
140 return false;
141 }
142
143 if (!data_type_finder_sp)
144 return false;
145 m_element_type = data_type_finder_sp->GetCompilerType().GetPointeeType();
146 if (llvm::Optional<uint64_t> size = m_element_type.GetByteSize(nullptr)) {
147 m_element_size = *size;
148
149 if (m_element_size > 0) {
150 // store raw pointers or end up with a circular dependency
151 m_start =
152 m_backend.GetChildMemberWithName(ConstString("__begin_"), true).get();
153 m_finish =
154 m_backend.GetChildMemberWithName(ConstString("__end_"), true).get();
155 }
156 }
157 return false;
158 }
159
160 bool lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::
MightHaveChildren()161 MightHaveChildren() {
162 return true;
163 }
164
165 size_t lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::
GetIndexOfChildWithName(ConstString name)166 GetIndexOfChildWithName(ConstString name) {
167 if (!m_start || !m_finish)
168 return UINT32_MAX;
169 return ExtractIndexFromString(name.GetCString());
170 }
171
172 lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::
LibcxxVectorBoolSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)173 LibcxxVectorBoolSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
174 : SyntheticChildrenFrontEnd(*valobj_sp), m_bool_type(), m_exe_ctx_ref(),
175 m_children() {
176 if (valobj_sp) {
177 Update();
178 m_bool_type =
179 valobj_sp->GetCompilerType().GetBasicTypeFromAST(lldb::eBasicTypeBool);
180 }
181 }
182
183 size_t lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::
CalculateNumChildren()184 CalculateNumChildren() {
185 return m_count;
186 }
187
188 lldb::ValueObjectSP
GetChildAtIndex(size_t idx)189 lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::GetChildAtIndex(
190 size_t idx) {
191 auto iter = m_children.find(idx), end = m_children.end();
192 if (iter != end)
193 return iter->second;
194 if (idx >= m_count)
195 return {};
196 if (m_base_data_address == 0 || m_count == 0)
197 return {};
198 if (!m_bool_type)
199 return {};
200 size_t byte_idx = (idx >> 3); // divide by 8 to get byte index
201 size_t bit_index = (idx & 7); // efficient idx % 8 for bit index
202 lldb::addr_t byte_location = m_base_data_address + byte_idx;
203 ProcessSP process_sp(m_exe_ctx_ref.GetProcessSP());
204 if (!process_sp)
205 return {};
206 uint8_t byte = 0;
207 uint8_t mask = 0;
208 Status err;
209 size_t bytes_read = process_sp->ReadMemory(byte_location, &byte, 1, err);
210 if (err.Fail() || bytes_read == 0)
211 return {};
212 mask = 1 << bit_index;
213 bool bit_set = ((byte & mask) != 0);
214 llvm::Optional<uint64_t> size = m_bool_type.GetByteSize(nullptr);
215 if (!size)
216 return {};
217 WritableDataBufferSP buffer_sp(new DataBufferHeap(*size, 0));
218 if (bit_set && buffer_sp && buffer_sp->GetBytes()) {
219 // regardless of endianness, anything non-zero is true
220 *(buffer_sp->GetBytes()) = 1;
221 }
222 StreamString name;
223 name.Printf("[%" PRIu64 "]", (uint64_t)idx);
224 ValueObjectSP retval_sp(CreateValueObjectFromData(
225 name.GetString(),
226 DataExtractor(buffer_sp, process_sp->GetByteOrder(),
227 process_sp->GetAddressByteSize()),
228 m_exe_ctx_ref, m_bool_type));
229 if (retval_sp)
230 m_children[idx] = retval_sp;
231 return retval_sp;
232 }
233
234 /*(std::__1::vector<std::__1::allocator<bool> >) vBool = {
235 __begin_ = 0x00000001001000e0
236 __size_ = 56
237 __cap_alloc_ = {
238 std::__1::__libcpp_compressed_pair_imp<unsigned long,
239 std::__1::allocator<unsigned long> > = {
240 __first_ = 1
241 }
242 }
243 }*/
244
Update()245 bool lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::Update() {
246 m_children.clear();
247 ValueObjectSP valobj_sp = m_backend.GetSP();
248 if (!valobj_sp)
249 return false;
250 m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
251 ValueObjectSP size_sp(
252 valobj_sp->GetChildMemberWithName(ConstString("__size_"), true));
253 if (!size_sp)
254 return false;
255 m_count = size_sp->GetValueAsUnsigned(0);
256 if (!m_count)
257 return true;
258 ValueObjectSP begin_sp(
259 valobj_sp->GetChildMemberWithName(ConstString("__begin_"), true));
260 if (!begin_sp) {
261 m_count = 0;
262 return false;
263 }
264 m_base_data_address = begin_sp->GetValueAsUnsigned(0);
265 if (!m_base_data_address) {
266 m_count = 0;
267 return false;
268 }
269 return false;
270 }
271
272 size_t lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::
GetIndexOfChildWithName(ConstString name)273 GetIndexOfChildWithName(ConstString name) {
274 if (!m_count || !m_base_data_address)
275 return UINT32_MAX;
276 const char *item_name = name.GetCString();
277 uint32_t idx = ExtractIndexFromString(item_name);
278 if (idx < UINT32_MAX && idx >= CalculateNumChildren())
279 return UINT32_MAX;
280 return idx;
281 }
282
283 lldb_private::SyntheticChildrenFrontEnd *
LibcxxStdVectorSyntheticFrontEndCreator(CXXSyntheticChildren *,lldb::ValueObjectSP valobj_sp)284 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEndCreator(
285 CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
286 if (!valobj_sp)
287 return nullptr;
288 CompilerType type = valobj_sp->GetCompilerType();
289 if (!type.IsValid() || type.GetNumTemplateArguments() == 0)
290 return nullptr;
291 CompilerType arg_type = type.GetTypeTemplateArgument(0);
292 if (arg_type.GetTypeName() == "bool")
293 return new LibcxxVectorBoolSyntheticFrontEnd(valobj_sp);
294 return new LibcxxStdVectorSyntheticFrontEnd(valobj_sp);
295 }
296