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;
39 ValueObject *m_finish;
40 CompilerType m_element_type;
41 uint32_t m_element_size;
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;
62 lldb::addr_t m_base_data_address;
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_start(nullptr),
72 m_finish(nullptr), m_element_type(), m_element_size(0) {
73 if (valobj_sp)
74 Update();
75 }
76
77 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::
~LibcxxStdVectorSyntheticFrontEnd()78 ~LibcxxStdVectorSyntheticFrontEnd() {
79 // these need to stay around because they are child objects who will follow
80 // their parent's life cycle
81 // delete m_start;
82 // delete m_finish;
83 }
84
85 size_t lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::
CalculateNumChildren()86 CalculateNumChildren() {
87 if (!m_start || !m_finish)
88 return 0;
89 uint64_t start_val = m_start->GetValueAsUnsigned(0);
90 uint64_t finish_val = m_finish->GetValueAsUnsigned(0);
91
92 if (start_val == 0 || finish_val == 0)
93 return 0;
94
95 if (start_val >= finish_val)
96 return 0;
97
98 size_t num_children = (finish_val - start_val);
99 if (num_children % m_element_size)
100 return 0;
101 return num_children / m_element_size;
102 }
103
104 lldb::ValueObjectSP
GetChildAtIndex(size_t idx)105 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::GetChildAtIndex(
106 size_t idx) {
107 if (!m_start || !m_finish)
108 return lldb::ValueObjectSP();
109
110 uint64_t offset = idx * m_element_size;
111 offset = offset + m_start->GetValueAsUnsigned(0);
112 StreamString name;
113 name.Printf("[%" PRIu64 "]", (uint64_t)idx);
114 return CreateValueObjectFromAddress(name.GetString(), offset,
115 m_backend.GetExecutionContextRef(),
116 m_element_type);
117 }
118
Update()119 bool lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::Update() {
120 m_start = m_finish = nullptr;
121 ValueObjectSP data_type_finder_sp(
122 m_backend.GetChildMemberWithName(ConstString("__end_cap_"), true));
123 if (!data_type_finder_sp)
124 return false;
125
126 switch (data_type_finder_sp->GetCompilerType().GetNumDirectBaseClasses()) {
127 case 1:
128 // Assume a pre llvm r300140 __compressed_pair implementation:
129 data_type_finder_sp = data_type_finder_sp->GetChildMemberWithName(
130 ConstString("__first_"), true);
131 break;
132 case 2: {
133 // Assume a post llvm r300140 __compressed_pair implementation:
134 ValueObjectSP first_elem_parent_sp =
135 data_type_finder_sp->GetChildAtIndex(0, true);
136 data_type_finder_sp = first_elem_parent_sp->GetChildMemberWithName(
137 ConstString("__value_"), true);
138 break;
139 }
140 default:
141 return false;
142 }
143
144 if (!data_type_finder_sp)
145 return false;
146 m_element_type = data_type_finder_sp->GetCompilerType().GetPointeeType();
147 if (llvm::Optional<uint64_t> size = m_element_type.GetByteSize(nullptr)) {
148 m_element_size = *size;
149
150 if (m_element_size > 0) {
151 // store raw pointers or end up with a circular dependency
152 m_start =
153 m_backend.GetChildMemberWithName(ConstString("__begin_"), true).get();
154 m_finish =
155 m_backend.GetChildMemberWithName(ConstString("__end_"), true).get();
156 }
157 }
158 return false;
159 }
160
161 bool lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::
MightHaveChildren()162 MightHaveChildren() {
163 return true;
164 }
165
166 size_t lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::
GetIndexOfChildWithName(ConstString name)167 GetIndexOfChildWithName(ConstString name) {
168 if (!m_start || !m_finish)
169 return UINT32_MAX;
170 return ExtractIndexFromString(name.GetCString());
171 }
172
173 lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::
LibcxxVectorBoolSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)174 LibcxxVectorBoolSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
175 : SyntheticChildrenFrontEnd(*valobj_sp), m_bool_type(), m_exe_ctx_ref(),
176 m_count(0), m_base_data_address(0), m_children() {
177 if (valobj_sp) {
178 Update();
179 m_bool_type =
180 valobj_sp->GetCompilerType().GetBasicTypeFromAST(lldb::eBasicTypeBool);
181 }
182 }
183
184 size_t lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::
CalculateNumChildren()185 CalculateNumChildren() {
186 return m_count;
187 }
188
189 lldb::ValueObjectSP
GetChildAtIndex(size_t idx)190 lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::GetChildAtIndex(
191 size_t idx) {
192 auto iter = m_children.find(idx), end = m_children.end();
193 if (iter != end)
194 return iter->second;
195 if (idx >= m_count)
196 return {};
197 if (m_base_data_address == 0 || m_count == 0)
198 return {};
199 if (!m_bool_type)
200 return {};
201 size_t byte_idx = (idx >> 3); // divide by 8 to get byte index
202 size_t bit_index = (idx & 7); // efficient idx % 8 for bit index
203 lldb::addr_t byte_location = m_base_data_address + byte_idx;
204 ProcessSP process_sp(m_exe_ctx_ref.GetProcessSP());
205 if (!process_sp)
206 return {};
207 uint8_t byte = 0;
208 uint8_t mask = 0;
209 Status err;
210 size_t bytes_read = process_sp->ReadMemory(byte_location, &byte, 1, err);
211 if (err.Fail() || bytes_read == 0)
212 return {};
213 mask = 1 << bit_index;
214 bool bit_set = ((byte & mask) != 0);
215 llvm::Optional<uint64_t> size = m_bool_type.GetByteSize(nullptr);
216 if (!size)
217 return {};
218 DataBufferSP buffer_sp(new DataBufferHeap(*size, 0));
219 if (bit_set && buffer_sp && buffer_sp->GetBytes()) {
220 // regardless of endianness, anything non-zero is true
221 *(buffer_sp->GetBytes()) = 1;
222 }
223 StreamString name;
224 name.Printf("[%" PRIu64 "]", (uint64_t)idx);
225 ValueObjectSP retval_sp(CreateValueObjectFromData(
226 name.GetString(),
227 DataExtractor(buffer_sp, process_sp->GetByteOrder(),
228 process_sp->GetAddressByteSize()),
229 m_exe_ctx_ref, m_bool_type));
230 if (retval_sp)
231 m_children[idx] = retval_sp;
232 return retval_sp;
233 }
234
235 /*(std::__1::vector<std::__1::allocator<bool> >) vBool = {
236 __begin_ = 0x00000001001000e0
237 __size_ = 56
238 __cap_alloc_ = {
239 std::__1::__libcpp_compressed_pair_imp<unsigned long,
240 std::__1::allocator<unsigned long> > = {
241 __first_ = 1
242 }
243 }
244 }*/
245
Update()246 bool lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::Update() {
247 m_children.clear();
248 ValueObjectSP valobj_sp = m_backend.GetSP();
249 if (!valobj_sp)
250 return false;
251 m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
252 ValueObjectSP size_sp(
253 valobj_sp->GetChildMemberWithName(ConstString("__size_"), true));
254 if (!size_sp)
255 return false;
256 m_count = size_sp->GetValueAsUnsigned(0);
257 if (!m_count)
258 return true;
259 ValueObjectSP begin_sp(
260 valobj_sp->GetChildMemberWithName(ConstString("__begin_"), true));
261 if (!begin_sp) {
262 m_count = 0;
263 return false;
264 }
265 m_base_data_address = begin_sp->GetValueAsUnsigned(0);
266 if (!m_base_data_address) {
267 m_count = 0;
268 return false;
269 }
270 return false;
271 }
272
273 size_t lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::
GetIndexOfChildWithName(ConstString name)274 GetIndexOfChildWithName(ConstString name) {
275 if (!m_count || !m_base_data_address)
276 return UINT32_MAX;
277 const char *item_name = name.GetCString();
278 uint32_t idx = ExtractIndexFromString(item_name);
279 if (idx < UINT32_MAX && idx >= CalculateNumChildren())
280 return UINT32_MAX;
281 return idx;
282 }
283
284 lldb_private::SyntheticChildrenFrontEnd *
LibcxxStdVectorSyntheticFrontEndCreator(CXXSyntheticChildren *,lldb::ValueObjectSP valobj_sp)285 lldb_private::formatters::LibcxxStdVectorSyntheticFrontEndCreator(
286 CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
287 if (!valobj_sp)
288 return nullptr;
289 CompilerType type = valobj_sp->GetCompilerType();
290 if (!type.IsValid() || type.GetNumTemplateArguments() == 0)
291 return nullptr;
292 CompilerType arg_type = type.GetTypeTemplateArgument(0);
293 if (arg_type.GetTypeName() == "bool")
294 return new LibcxxVectorBoolSyntheticFrontEnd(valobj_sp);
295 return new LibcxxStdVectorSyntheticFrontEnd(valobj_sp);
296 }
297