LLDB  mainline
ValueObjectDynamicValue.cpp
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1 //===-- ValueObjectDynamicValue.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 
10 #include "lldb/Core/Value.h"
11 #include "lldb/Core/ValueObject.h"
13 #include "lldb/Symbol/Type.h"
16 #include "lldb/Target/Process.h"
17 #include "lldb/Target/Target.h"
19 #include "lldb/Utility/Log.h"
20 #include "lldb/Utility/Logging.h"
21 #include "lldb/Utility/Scalar.h"
22 #include "lldb/Utility/Status.h"
23 #include "lldb/lldb-types.h"
24 
25 #include <string.h>
26 namespace lldb_private {
27 class Declaration;
28 }
29 
30 using namespace lldb_private;
31 
33  ValueObject &parent, lldb::DynamicValueType use_dynamic)
34  : ValueObject(parent), m_address(), m_dynamic_type_info(),
35  m_use_dynamic(use_dynamic) {
36  SetName(parent.GetName());
37 }
38 
40  m_owning_valobj_sp.reset();
41 }
42 
44  const bool success = UpdateValueIfNeeded(false);
45  if (success) {
47  return m_value.GetCompilerType();
48  else
49  return m_parent->GetCompilerType();
50  }
51  return m_parent->GetCompilerType();
52 }
53 
55  const bool success = UpdateValueIfNeeded(false);
56  if (success) {
59  }
60  return m_parent->GetTypeName();
61 }
62 
64  const bool success = UpdateValueIfNeeded(false);
65  if (success && m_type_impl.IsValid()) {
66  return m_type_impl;
67  }
68  return m_parent->GetTypeImpl();
69 }
70 
72  const bool success = UpdateValueIfNeeded(false);
73  if (success) {
76  }
78 }
79 
81  const bool success = UpdateValueIfNeeded(false);
82  if (success) {
87  }
88  return m_parent->GetDisplayTypeName();
89 }
90 
92  const bool success = UpdateValueIfNeeded(false);
93  if (success && m_dynamic_type_info.HasType()) {
95  auto children_count = GetCompilerType().GetNumChildren(true, &exe_ctx);
96  return children_count <= max ? children_count : max;
97  } else
98  return m_parent->GetNumChildren(max);
99 }
100 
102  const bool success = UpdateValueIfNeeded(false);
103  if (success && m_dynamic_type_info.HasType()) {
105  return m_value.GetValueByteSize(nullptr, &exe_ctx);
106  } else
107  return m_parent->GetByteSize();
108 }
109 
111  return m_parent->GetValueType();
112 }
113 
115  SetValueIsValid(false);
116  m_error.Clear();
117 
118  if (!m_parent->UpdateValueIfNeeded(false)) {
119  // The dynamic value failed to get an error, pass the error along
120  if (m_error.Success() && m_parent->GetError().Fail())
122  return false;
123  }
124 
125  // Setting our type_sp to NULL will route everything back through our parent
126  // which is equivalent to not using dynamic values.
129  return true;
130  }
131 
133  Target *target = exe_ctx.GetTargetPtr();
134  if (target) {
137  }
138 
139  // First make sure our Type and/or Address haven't changed:
140  Process *process = exe_ctx.GetProcessPtr();
141  if (!process)
142  return false;
143 
144  TypeAndOrName class_type_or_name;
145  Address dynamic_address;
146  bool found_dynamic_type = false;
147  Value::ValueType value_type;
148 
149  LanguageRuntime *runtime = nullptr;
150 
152  if (known_type != lldb::eLanguageTypeUnknown &&
153  known_type != lldb::eLanguageTypeC) {
154  runtime = process->GetLanguageRuntime(known_type);
155  if (runtime)
156  found_dynamic_type = runtime->GetDynamicTypeAndAddress(
157  *m_parent, m_use_dynamic, class_type_or_name, dynamic_address,
158  value_type);
159  } else {
161  if (runtime)
162  found_dynamic_type = runtime->GetDynamicTypeAndAddress(
163  *m_parent, m_use_dynamic, class_type_or_name, dynamic_address,
164  value_type);
165 
166  if (!found_dynamic_type) {
167  runtime = process->GetLanguageRuntime(lldb::eLanguageTypeObjC);
168  if (runtime)
169  found_dynamic_type = runtime->GetDynamicTypeAndAddress(
170  *m_parent, m_use_dynamic, class_type_or_name, dynamic_address,
171  value_type);
172  }
173  }
174 
175  // Getting the dynamic value may have run the program a bit, and so marked us
176  // as needing updating, but we really don't...
177 
179 
180  if (runtime && found_dynamic_type) {
181  if (class_type_or_name.HasType()) {
182  m_type_impl =
184  runtime->FixUpDynamicType(class_type_or_name, *m_parent)
185  .GetCompilerType());
186  } else {
187  m_type_impl.Clear();
188  }
189  } else {
190  m_type_impl.Clear();
191  }
192 
193  // If we don't have a dynamic type, then make ourselves just a echo of our
194  // parent. Or we could return false, and make ourselves an echo of our
195  // parent?
196  if (!found_dynamic_type) {
198  SetValueDidChange(true);
202  m_error = m_value.GetValueAsData(&exe_ctx, m_data, GetModule().get());
203  return m_error.Success();
204  }
205 
206  Value old_value(m_value);
207 
209 
210  bool has_changed_type = false;
211 
212  if (!m_dynamic_type_info) {
213  m_dynamic_type_info = class_type_or_name;
214  has_changed_type = true;
215  } else if (class_type_or_name != m_dynamic_type_info) {
216  // We are another type, we need to tear down our children...
217  m_dynamic_type_info = class_type_or_name;
218  SetValueDidChange(true);
219  has_changed_type = true;
220  }
221 
222  if (has_changed_type)
224 
225  if (!m_address.IsValid() || m_address != dynamic_address) {
226  if (m_address.IsValid())
227  SetValueDidChange(true);
228 
229  // We've moved, so we should be fine...
230  m_address = dynamic_address;
231  lldb::TargetSP target_sp(GetTargetSP());
232  lldb::addr_t load_address = m_address.GetLoadAddress(target_sp.get());
233  m_value.GetScalar() = load_address;
234  }
235 
236  if (runtime)
239 
241 
242  m_value.SetValueType(value_type);
243 
244  if (has_changed_type && log)
245  LLDB_LOGF(log, "[%s %p] has a new dynamic type %s", GetName().GetCString(),
246  static_cast<void *>(this), GetTypeName().GetCString());
247 
249  // The variable value is in the Scalar value inside the m_value. We can
250  // point our m_data right to it.
251  m_error = m_value.GetValueAsData(&exe_ctx, m_data, GetModule().get());
252  if (m_error.Success()) {
253  if (!CanProvideValue()) {
254  // this value object represents an aggregate type whose children have
255  // values, but this object does not. So we say we are changed if our
256  // location has changed.
258  m_value.GetScalar() != old_value.GetScalar());
259  }
260 
261  SetValueIsValid(true);
262  return true;
263  }
264  }
265 
266  // We get here if we've failed above...
267  SetValueIsValid(false);
268  return false;
269 }
270 
272 
274  Status &error) {
275  if (!UpdateValueIfNeeded(false)) {
276  error.SetErrorString("unable to read value");
277  return false;
278  }
279 
280  uint64_t my_value = GetValueAsUnsigned(UINT64_MAX);
281  uint64_t parent_value = m_parent->GetValueAsUnsigned(UINT64_MAX);
282 
283  if (my_value == UINT64_MAX || parent_value == UINT64_MAX) {
284  error.SetErrorString("unable to read value");
285  return false;
286  }
287 
288  // if we are at an offset from our parent, in order to set ourselves
289  // correctly we would need to change the new value so that it refers to the
290  // correct dynamic type. we choose not to deal with that - if anything more
291  // than a value overwrite is required, you should be using the expression
292  // parser instead of the value editing facility
293  if (my_value != parent_value) {
294  // but NULL'ing out a value should always be allowed
295  if (strcmp(value_str, "0")) {
296  error.SetErrorString(
297  "unable to modify dynamic value, use 'expression' command");
298  return false;
299  }
300  }
301 
302  bool ret_val = m_parent->SetValueFromCString(value_str, error);
303  SetNeedsUpdate();
304  return ret_val;
305 }
306 
308  if (!UpdateValueIfNeeded(false)) {
309  error.SetErrorString("unable to read value");
310  return false;
311  }
312 
313  uint64_t my_value = GetValueAsUnsigned(UINT64_MAX);
314  uint64_t parent_value = m_parent->GetValueAsUnsigned(UINT64_MAX);
315 
316  if (my_value == UINT64_MAX || parent_value == UINT64_MAX) {
317  error.SetErrorString("unable to read value");
318  return false;
319  }
320 
321  // if we are at an offset from our parent, in order to set ourselves
322  // correctly we would need to change the new value so that it refers to the
323  // correct dynamic type. we choose not to deal with that - if anything more
324  // than a value overwrite is required, you should be using the expression
325  // parser instead of the value editing facility
326  if (my_value != parent_value) {
327  // but NULL'ing out a value should always be allowed
328  lldb::offset_t offset = 0;
329 
330  if (data.GetAddress(&offset) != 0) {
331  error.SetErrorString(
332  "unable to modify dynamic value, use 'expression' command");
333  return false;
334  }
335  }
336 
337  bool ret_val = m_parent->SetData(data, error);
338  SetNeedsUpdate();
339  return ret_val;
340 }
341 
343  lldb::LanguageType lang) {
345  if (m_parent)
347 }
348 
351  if (m_parent)
354  } else
356 }
357 
359  if (m_parent)
361  return false;
362 }
363 
365  if (m_parent)
368 }
369 
371  if (m_parent)
372  return m_parent->GetDeclaration(decl);
373 
374  return ValueObject::GetDeclaration(decl);
375 }
376 
378  if (m_parent)
379  return m_parent->GetLanguageFlags();
380  return this->ValueObject::GetLanguageFlags();
381 }
382 
384  if (m_parent)
385  m_parent->SetLanguageFlags(flags);
386  else
387  this->ValueObject::SetLanguageFlags(flags);
388 }
An data extractor class.
Definition: DataExtractor.h:46
CompilerType GetCompilerType()
A class that represents a running process on the host machine.
virtual lldb::LanguageType GetPreferredDisplayLanguage()
const ArchSpec & GetArchitecture() const
Definition: Target.h:941
Sometimes you can find the name of the type corresponding to an object, but we don&#39;t have debug infor...
Definition: Type.h:381
CompilerType GetCompilerType() const
Definition: Type.h:395
uint32_t GetAddressByteSize() const
Returns the size in bytes of an address of the current architecture.
Definition: ArchSpec.cpp:730
virtual ConstString GetTypeName()
lldb::addr_t GetLoadAddress(Target *target) const
Get the load address.
Definition: Address.cpp:310
ConstString GetName() const
virtual bool SetValueFromCString(const char *value_str, Status &error)
void SetPreferredDisplayLanguage(lldb::LanguageType)
virtual lldb::LanguageType GetObjectRuntimeLanguage()
size_t CalculateNumChildren(uint32_t max) override
bool SetData(DataExtractor &data, Status &error) override
void SetValueDidChange(bool value_changed)
virtual uint64_t GetLanguageFlags()
void SetValueType(ValueType value_type)
Definition: Value.h:144
"lldb/Target/ExecutionContext.h" A class that contains an execution context.
void SetAddressByteSize(uint32_t addr_size)
Set the address byte size.
const Status & GetError()
bool GetDeclaration(Declaration &decl) override
lldb::TargetSP GetTargetSP() const
Definition: ValueObject.h:335
uint32_t GetNumChildren(bool omit_empty_base_classes, const ExecutionContext *exe_ctx) const
Status GetValueAsData(ExecutionContext *exe_ctx, DataExtractor &data, Module *module)
Definition: Value.cpp:316
virtual lldb::ModuleSP GetModule()
lldb::LanguageType m_preferred_display_language
Definition: ValueObject.h:878
virtual ConstString GetQualifiedTypeName()
virtual bool SetData(DataExtractor &data, Status &error)
lldb::LanguageType GetPreferredDisplayLanguage() override
uint64_t GetAddress(lldb::offset_t *offset_ptr) const
Extract an address from *offset_ptr.
ValueType GetValueType() const
Definition: Value.cpp:114
Target * GetTargetPtr() const
Returns a pointer to the target object.
virtual TypeImpl GetTypeImpl()
LanguageType
Programming language type.
virtual bool CanProvideValue()
uint64_t offset_t
Definition: lldb-types.h:87
Log * GetLogIfAllCategoriesSet(uint32_t mask)
Definition: Logging.cpp:58
EvaluationPoint m_update_point
Definition: ValueObject.h:822
void SetLanguageFlags(uint64_t flags) override
void Clear()
Clear the object state.
Definition: Status.cpp:168
void SetErrorString(llvm::StringRef err_str)
Set the current error string to err_str.
Definition: Status.cpp:242
A plug-in interface definition class for debugging a process.
Definition: Process.h:362
Process * GetProcessPtr() const
Returns a pointer to the process object.
lldb::ByteOrder GetByteOrder() const
Returns the byte order for the architecture specification.
Definition: ArchSpec.cpp:777
const ExecutionContextRef & GetExecutionContextRef() const
Definition: ValueObject.h:331
virtual bool IsInScope()
Definition: ValueObject.h:411
ConstString GetDisplayTypeName() const
bool Success() const
Test for success condition.
Definition: Status.cpp:288
const CompilerType & GetCompilerType()
Definition: Value.cpp:239
bool IsValid() const
Check if the object state is valid.
Definition: Address.h:332
A section + offset based address class.
Definition: Address.h:59
virtual uint64_t GetByteSize()=0
virtual bool IsSyntheticChildrenGenerated()
void SetValueIsValid(bool valid)
bool HasName() const
Definition: Type.cpp:789
#define LLDB_LOGF(log,...)
Definition: Log.h:249
uint64_t addr_t
Definition: lldb-types.h:83
bool UpdateValueIfNeeded(bool update_format=true)
A uniqued constant string class.
Definition: ConstString.h:40
Unknown or invalid language value.
virtual bool GetDeclaration(Declaration &decl)
bool IsValid() const
Definition: Type.cpp:881
bool Fail() const
Test for error condition.
Definition: Status.cpp:182
lldb::ValueType GetValueType() const override
Non-standardized C, such as K&R.
virtual uint64_t GetValueAsUnsigned(uint64_t fail_value, bool *success=nullptr)
virtual bool GetDynamicTypeAndAddress(ValueObject &in_value, lldb::DynamicValueType use_dynamic, TypeAndOrName &class_type_or_name, Address &address, Value::ValueType &value_type)=0
ConstString GetName() const
Definition: Type.cpp:750
Represents a generic type in a programming language.
Definition: CompilerType.h:33
LanguageRuntime * GetLanguageRuntime(lldb::LanguageType language)
Definition: Process.cpp:1607
virtual lldb::ValueType GetValueType() const =0
virtual TypeAndOrName FixUpDynamicType(const TypeAndOrName &type_and_or_name, ValueObject &static_value)=0
uint64_t GetValueByteSize(Status *error_ptr, ExecutionContext *exe_ctx)
Definition: Value.cpp:211
ValueObjectDynamicValue(ValueObject &parent, lldb::DynamicValueType use_dynamic)
const Value & GetValue() const
size_t GetNumChildren(uint32_t max=UINT32_MAX)
virtual void SetLanguageFlags(uint64_t flags)
void SetCompilerType(const CompilerType &compiler_type)
Definition: Value.cpp:268
bool SetValueFromCString(const char *value_str, Status &error) override
#define LIBLLDB_LOG_TYPES
Definition: Logging.h:33
const Scalar & GetScalar() const
Definition: Value.h:168
void SetName(ConstString name)
virtual void SetSyntheticChildrenGenerated(bool b)
virtual ConstString GetDisplayTypeName()
bool HasType() const
Definition: Type.h:411
A class that describes the declaration location of a lldb object.
Definition: Declaration.h:24
#define UINT64_MAX
Definition: lldb-defines.h:35
Address m_address
The variable that this value object is based upon.
An error handling class.
Definition: Status.h:44
void SetByteOrder(lldb::ByteOrder byte_order)
Set the byte_order value.