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LibCxxVector.cpp
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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
14#include <optional>
15
16using namespace lldb;
17using namespace lldb_private;
18using namespace lldb_private::formatters;
19
20namespace lldb_private {
21namespace formatters {
23public:
25
27
28 llvm::Expected<uint32_t> CalculateNumChildren() override;
29
30 lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override;
31
33
34 bool MightHaveChildren() override;
35
36 size_t GetIndexOfChildWithName(ConstString name) override;
37
38private:
39 ValueObject *m_start = nullptr;
42 uint32_t m_element_size = 0;
43};
44
46public:
48
49 llvm::Expected<uint32_t> CalculateNumChildren() override;
50
51 lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override;
52
54
55 bool MightHaveChildren() override { return true; }
56
57 size_t GetIndexOfChildWithName(ConstString name) override;
58
59private:
62 uint64_t m_count = 0;
64 std::map<size_t, lldb::ValueObjectSP> m_children;
65};
66
67} // namespace formatters
68} // namespace lldb_private
69
72 : SyntheticChildrenFrontEnd(*valobj_sp), m_element_type() {
73 if (valobj_sp)
74 Update();
75}
76
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
85llvm::Expected<uint32_t> lldb_private::formatters::
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
106 uint32_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
121 m_start = m_finish = nullptr;
122 ValueObjectSP data_type_finder_sp(
123 m_backend.GetChildMemberWithName("__end_cap_"));
124 if (!data_type_finder_sp)
126
127 data_type_finder_sp =
128 GetFirstValueOfLibCXXCompressedPair(*data_type_finder_sp);
129 if (!data_type_finder_sp)
131
132 m_element_type = data_type_finder_sp->GetCompilerType().GetPointeeType();
133 if (std::optional<uint64_t> size = m_element_type.GetByteSize(nullptr)) {
134 m_element_size = *size;
135
136 if (m_element_size > 0) {
137 // store raw pointers or end up with a circular dependency
138 m_start = m_backend.GetChildMemberWithName("__begin_").get();
139 m_finish = m_backend.GetChildMemberWithName("__end_").get();
140 }
141 }
143}
144
147 return true;
148}
149
152 if (!m_start || !m_finish)
153 return UINT32_MAX;
154 return ExtractIndexFromString(name.GetCString());
155}
156
159 : SyntheticChildrenFrontEnd(*valobj_sp), m_bool_type(), m_exe_ctx_ref(),
160 m_children() {
161 if (valobj_sp) {
162 Update();
164 valobj_sp->GetCompilerType().GetBasicTypeFromAST(lldb::eBasicTypeBool);
165 }
166}
167
168llvm::Expected<uint32_t> lldb_private::formatters::
170 return m_count;
171}
172
175 uint32_t idx) {
176 auto iter = m_children.find(idx), end = m_children.end();
177 if (iter != end)
178 return iter->second;
179 if (idx >= m_count)
180 return {};
181 if (m_base_data_address == 0 || m_count == 0)
182 return {};
183 if (!m_bool_type)
184 return {};
185 size_t byte_idx = (idx >> 3); // divide by 8 to get byte index
186 size_t bit_index = (idx & 7); // efficient idx % 8 for bit index
187 lldb::addr_t byte_location = m_base_data_address + byte_idx;
188 ProcessSP process_sp(m_exe_ctx_ref.GetProcessSP());
189 if (!process_sp)
190 return {};
191 uint8_t byte = 0;
192 uint8_t mask = 0;
193 Status err;
194 size_t bytes_read = process_sp->ReadMemory(byte_location, &byte, 1, err);
195 if (err.Fail() || bytes_read == 0)
196 return {};
197 mask = 1 << bit_index;
198 bool bit_set = ((byte & mask) != 0);
199 std::optional<uint64_t> size = m_bool_type.GetByteSize(nullptr);
200 if (!size)
201 return {};
202 WritableDataBufferSP buffer_sp(new DataBufferHeap(*size, 0));
203 if (bit_set && buffer_sp && buffer_sp->GetBytes()) {
204 // regardless of endianness, anything non-zero is true
205 *(buffer_sp->GetBytes()) = 1;
206 }
207 StreamString name;
208 name.Printf("[%" PRIu64 "]", (uint64_t)idx);
209 ValueObjectSP retval_sp(CreateValueObjectFromData(
210 name.GetString(),
211 DataExtractor(buffer_sp, process_sp->GetByteOrder(),
212 process_sp->GetAddressByteSize()),
213 m_exe_ctx_ref, m_bool_type));
214 if (retval_sp)
215 m_children[idx] = retval_sp;
216 return retval_sp;
217}
218
219/*(std::__1::vector<std::__1::allocator<bool> >) vBool = {
220 __begin_ = 0x00000001001000e0
221 __size_ = 56
222 __cap_alloc_ = {
223 std::__1::__libcpp_compressed_pair_imp<unsigned long,
224 std::__1::allocator<unsigned long> > = {
225 __first_ = 1
226 }
227 }
228 }*/
229
232 m_children.clear();
233 ValueObjectSP valobj_sp = m_backend.GetSP();
234 if (!valobj_sp)
236 m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
237 ValueObjectSP size_sp(valobj_sp->GetChildMemberWithName("__size_"));
238 if (!size_sp)
240 m_count = size_sp->GetValueAsUnsigned(0);
241 if (!m_count)
243 ValueObjectSP begin_sp(valobj_sp->GetChildMemberWithName("__begin_"));
244 if (!begin_sp) {
245 m_count = 0;
247 }
248 m_base_data_address = begin_sp->GetValueAsUnsigned(0);
249 if (!m_base_data_address) {
250 m_count = 0;
252 }
254}
255
258 if (!m_count || !m_base_data_address)
259 return UINT32_MAX;
260 const char *item_name = name.GetCString();
261 uint32_t idx = ExtractIndexFromString(item_name);
262 if (idx < UINT32_MAX && idx >= CalculateNumChildrenIgnoringErrors())
263 return UINT32_MAX;
264 return idx;
265}
266
270 if (!valobj_sp)
271 return nullptr;
272 CompilerType type = valobj_sp->GetCompilerType();
273 if (!type.IsValid() || type.GetNumTemplateArguments() == 0)
274 return nullptr;
275 CompilerType arg_type = type.GetTypeTemplateArgument(0);
276 if (arg_type.GetTypeName() == "bool")
277 return new LibcxxVectorBoolSyntheticFrontEnd(valobj_sp);
278 return new LibcxxStdVectorSyntheticFrontEnd(valobj_sp);
279}
Generic representation of a type in a programming language.
Definition: CompilerType.h:36
CompilerType GetTypeTemplateArgument(size_t idx, bool expand_pack=false) const
CompilerType GetBasicTypeFromAST(lldb::BasicType basic_type) const
Create related types using the current type's AST.
size_t GetNumTemplateArguments(bool expand_pack=false) const
Return the number of template arguments the type has.
ConstString GetTypeName(bool BaseOnly=false) const
A uniqued constant string class.
Definition: ConstString.h:40
const char * GetCString() const
Get the string value as a C string.
Definition: ConstString.h:214
A subclass of DataBuffer that stores a data buffer on the heap.
An data extractor class.
Definition: DataExtractor.h:48
Execution context objects refer to objects in the execution of the program that is being debugged.
An error handling class.
Definition: Status.h:44
bool Fail() const
Test for error condition.
Definition: Status.cpp:181
llvm::StringRef GetString() const
size_t Printf(const char *format,...) __attribute__((format(printf
Output printf formatted output to the stream.
Definition: Stream.cpp:134
llvm::Expected< uint32_t > CalculateNumChildren() override
lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override
lldb::ChildCacheState Update() override
This function is assumed to always succeed and if it fails, the front-end should know to deal with it...
size_t GetIndexOfChildWithName(ConstString name) override
LibcxxStdVectorSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
std::map< size_t, lldb::ValueObjectSP > m_children
llvm::Expected< uint32_t > CalculateNumChildren() override
lldb::ChildCacheState Update() override
This function is assumed to always succeed and if it fails, the front-end should know to deal with it...
LibcxxVectorBoolSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
lldb::ValueObjectSP GetChildAtIndex(uint32_t idx) override
#define UINT32_MAX
Definition: lldb-defines.h:19
size_t ExtractIndexFromString(const char *item_name)
lldb::ValueObjectSP GetFirstValueOfLibCXXCompressedPair(ValueObject &pair)
Definition: LibCxx.cpp:49
SyntheticChildrenFrontEnd * LibcxxStdVectorSyntheticFrontEndCreator(CXXSyntheticChildren *, lldb::ValueObjectSP)
A class that represents a running process on the host machine.
Definition: SBAttachInfo.h:14
Definition: SBAddress.h:15
ChildCacheState
Specifies if children need to be re-computed after a call to SyntheticChildrenFrontEnd::Update.
@ eRefetch
Children need to be recomputed dynamically.
@ eReuse
Children did not change and don't need to be recomputed; re-use what we computed the last time we cal...
std::shared_ptr< lldb_private::ValueObject > ValueObjectSP
Definition: lldb-forward.h:472
std::shared_ptr< lldb_private::Process > ProcessSP
Definition: lldb-forward.h:381
std::shared_ptr< lldb_private::WritableDataBuffer > WritableDataBufferSP
Definition: lldb-forward.h:329
uint64_t addr_t
Definition: lldb-types.h:80