1 //===-- ValueObjectVariable.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
11 #include "lldb/Core/ValueObjectVariable.h"
12
13 // C Includes
14 // C++ Includes
15 // Other libraries and framework includes
16 // Project includes
17 #include "lldb/Core/Module.h"
18 #include "lldb/Core/RegisterValue.h"
19 #include "lldb/Core/ValueObjectList.h"
20 #include "lldb/Core/Value.h"
21
22 #include "lldb/Symbol/Function.h"
23 #include "lldb/Symbol/ObjectFile.h"
24 #include "lldb/Symbol/SymbolContext.h"
25 #include "lldb/Symbol/SymbolContextScope.h"
26 #include "lldb/Symbol/Type.h"
27 #include "lldb/Symbol/Variable.h"
28
29 #include "lldb/Target/ExecutionContext.h"
30 #include "lldb/Target/Process.h"
31 #include "lldb/Target/RegisterContext.h"
32 #include "lldb/Target/Target.h"
33 #include "lldb/Target/Thread.h"
34
35
36 using namespace lldb_private;
37
38 lldb::ValueObjectSP
Create(ExecutionContextScope * exe_scope,const lldb::VariableSP & var_sp)39 ValueObjectVariable::Create (ExecutionContextScope *exe_scope, const lldb::VariableSP &var_sp)
40 {
41 return (new ValueObjectVariable (exe_scope, var_sp))->GetSP();
42 }
43
ValueObjectVariable(ExecutionContextScope * exe_scope,const lldb::VariableSP & var_sp)44 ValueObjectVariable::ValueObjectVariable (ExecutionContextScope *exe_scope, const lldb::VariableSP &var_sp) :
45 ValueObject(exe_scope),
46 m_variable_sp(var_sp)
47 {
48 // Do not attempt to construct one of these objects with no variable!
49 assert (m_variable_sp.get() != NULL);
50 m_name = var_sp->GetName();
51 }
52
~ValueObjectVariable()53 ValueObjectVariable::~ValueObjectVariable()
54 {
55 }
56
57 ClangASTType
GetClangTypeImpl()58 ValueObjectVariable::GetClangTypeImpl ()
59 {
60 Type *var_type = m_variable_sp->GetType();
61 if (var_type)
62 return var_type->GetClangForwardType();
63 return ClangASTType();
64 }
65
66 ConstString
GetTypeName()67 ValueObjectVariable::GetTypeName()
68 {
69 Type * var_type = m_variable_sp->GetType();
70 if (var_type)
71 return var_type->GetName();
72 return ConstString();
73 }
74
75 ConstString
GetQualifiedTypeName()76 ValueObjectVariable::GetQualifiedTypeName()
77 {
78 Type * var_type = m_variable_sp->GetType();
79 if (var_type)
80 return var_type->GetQualifiedName();
81 return ConstString();
82 }
83
84 size_t
CalculateNumChildren()85 ValueObjectVariable::CalculateNumChildren()
86 {
87 ClangASTType type(GetClangType());
88
89 if (!type.IsValid())
90 return 0;
91
92 const bool omit_empty_base_classes = true;
93 return type.GetNumChildren(omit_empty_base_classes);
94 }
95
96 uint64_t
GetByteSize()97 ValueObjectVariable::GetByteSize()
98 {
99 ClangASTType type(GetClangType());
100
101 if (!type.IsValid())
102 return 0;
103
104 return type.GetByteSize();
105 }
106
107 lldb::ValueType
GetValueType() const108 ValueObjectVariable::GetValueType() const
109 {
110 if (m_variable_sp)
111 return m_variable_sp->GetScope();
112 return lldb::eValueTypeInvalid;
113 }
114
115 bool
UpdateValue()116 ValueObjectVariable::UpdateValue ()
117 {
118 SetValueIsValid (false);
119 m_error.Clear();
120
121 Variable *variable = m_variable_sp.get();
122 DWARFExpression &expr = variable->LocationExpression();
123
124 if (variable->GetLocationIsConstantValueData())
125 {
126 // expr doesn't contain DWARF bytes, it contains the constant variable
127 // value bytes themselves...
128 if (expr.GetExpressionData(m_data))
129 m_value.SetContext(Value::eContextTypeVariable, variable);
130 else
131 m_error.SetErrorString ("empty constant data");
132 // constant bytes can't be edited - sorry
133 m_resolved_value.SetContext(Value::eContextTypeInvalid, NULL);
134 }
135 else
136 {
137 lldb::addr_t loclist_base_load_addr = LLDB_INVALID_ADDRESS;
138 ExecutionContext exe_ctx (GetExecutionContextRef());
139
140 Target *target = exe_ctx.GetTargetPtr();
141 if (target)
142 {
143 m_data.SetByteOrder(target->GetArchitecture().GetByteOrder());
144 m_data.SetAddressByteSize(target->GetArchitecture().GetAddressByteSize());
145 }
146
147 if (expr.IsLocationList())
148 {
149 SymbolContext sc;
150 variable->CalculateSymbolContext (&sc);
151 if (sc.function)
152 loclist_base_load_addr = sc.function->GetAddressRange().GetBaseAddress().GetLoadAddress (target);
153 }
154 Value old_value(m_value);
155 if (expr.Evaluate (&exe_ctx, NULL, NULL, NULL, loclist_base_load_addr, NULL, m_value, &m_error))
156 {
157 m_resolved_value = m_value;
158 m_value.SetContext(Value::eContextTypeVariable, variable);
159
160 Value::ValueType value_type = m_value.GetValueType();
161
162 switch (value_type)
163 {
164 case Value::eValueTypeFileAddress:
165 SetAddressTypeOfChildren(eAddressTypeFile);
166 break;
167 case Value::eValueTypeHostAddress:
168 SetAddressTypeOfChildren(eAddressTypeHost);
169 break;
170 case Value::eValueTypeLoadAddress:
171 case Value::eValueTypeScalar:
172 case Value::eValueTypeVector:
173 SetAddressTypeOfChildren(eAddressTypeLoad);
174 break;
175 }
176
177 switch (value_type)
178 {
179 case Value::eValueTypeVector:
180 // fall through
181 case Value::eValueTypeScalar:
182 // The variable value is in the Scalar value inside the m_value.
183 // We can point our m_data right to it.
184 m_error = m_value.GetValueAsData (&exe_ctx, m_data, 0, GetModule().get());
185 break;
186
187 case Value::eValueTypeFileAddress:
188 case Value::eValueTypeLoadAddress:
189 case Value::eValueTypeHostAddress:
190 // The DWARF expression result was an address in the inferior
191 // process. If this variable is an aggregate type, we just need
192 // the address as the main value as all child variable objects
193 // will rely upon this location and add an offset and then read
194 // their own values as needed. If this variable is a simple
195 // type, we read all data for it into m_data.
196 // Make sure this type has a value before we try and read it
197
198 // If we have a file address, convert it to a load address if we can.
199 Process *process = exe_ctx.GetProcessPtr();
200 if (value_type == Value::eValueTypeFileAddress && process && process->IsAlive())
201 {
202 lldb::addr_t file_addr = m_value.GetScalar().ULongLong(LLDB_INVALID_ADDRESS);
203 if (file_addr != LLDB_INVALID_ADDRESS)
204 {
205 SymbolContext var_sc;
206 variable->CalculateSymbolContext(&var_sc);
207 if (var_sc.module_sp)
208 {
209 ObjectFile *objfile = var_sc.module_sp->GetObjectFile();
210 if (objfile)
211 {
212 Address so_addr(file_addr, objfile->GetSectionList());
213 lldb::addr_t load_addr = so_addr.GetLoadAddress (target);
214 if (load_addr != LLDB_INVALID_ADDRESS)
215 {
216 m_value.SetValueType(Value::eValueTypeLoadAddress);
217 m_value.GetScalar() = load_addr;
218 }
219 }
220 }
221 }
222 }
223
224 if (GetClangType().IsAggregateType())
225 {
226 // this value object represents an aggregate type whose
227 // children have values, but this object does not. So we
228 // say we are changed if our location has changed.
229 SetValueDidChange (value_type != old_value.GetValueType() || m_value.GetScalar() != old_value.GetScalar());
230 }
231 else
232 {
233 // Copy the Value and set the context to use our Variable
234 // so it can extract read its value into m_data appropriately
235 Value value(m_value);
236 value.SetContext(Value::eContextTypeVariable, variable);
237 m_error = value.GetValueAsData(&exe_ctx, m_data, 0, GetModule().get());
238 }
239 break;
240 }
241
242 SetValueIsValid (m_error.Success());
243 }
244 else
245 {
246 // could not find location, won't allow editing
247 m_resolved_value.SetContext(Value::eContextTypeInvalid, NULL);
248 }
249 }
250 return m_error.Success();
251 }
252
253
254
255 bool
IsInScope()256 ValueObjectVariable::IsInScope ()
257 {
258 const ExecutionContextRef &exe_ctx_ref = GetExecutionContextRef();
259 if (exe_ctx_ref.HasFrameRef())
260 {
261 ExecutionContext exe_ctx (exe_ctx_ref);
262 StackFrame *frame = exe_ctx.GetFramePtr();
263 if (frame)
264 {
265 return m_variable_sp->IsInScope (frame);
266 }
267 else
268 {
269 // This ValueObject had a frame at one time, but now we
270 // can't locate it, so return false since we probably aren't
271 // in scope.
272 return false;
273 }
274 }
275 // We have a variable that wasn't tied to a frame, which
276 // means it is a global and is always in scope.
277 return true;
278
279 }
280
281 lldb::ModuleSP
GetModule()282 ValueObjectVariable::GetModule()
283 {
284 if (m_variable_sp)
285 {
286 SymbolContextScope *sc_scope = m_variable_sp->GetSymbolContextScope();
287 if (sc_scope)
288 {
289 return sc_scope->CalculateSymbolContextModule();
290 }
291 }
292 return lldb::ModuleSP();
293 }
294
295 SymbolContextScope *
GetSymbolContextScope()296 ValueObjectVariable::GetSymbolContextScope()
297 {
298 if (m_variable_sp)
299 return m_variable_sp->GetSymbolContextScope();
300 return NULL;
301 }
302
303 bool
GetDeclaration(Declaration & decl)304 ValueObjectVariable::GetDeclaration (Declaration &decl)
305 {
306 if (m_variable_sp)
307 {
308 decl = m_variable_sp->GetDeclaration();
309 return true;
310 }
311 return false;
312 }
313
314 const char *
GetLocationAsCString()315 ValueObjectVariable::GetLocationAsCString ()
316 {
317 if (m_resolved_value.GetContextType() == Value::eContextTypeRegisterInfo)
318 return GetLocationAsCStringImpl(m_resolved_value,
319 m_data);
320 else
321 return ValueObject::GetLocationAsCString();
322 }
323
324 bool
SetValueFromCString(const char * value_str,Error & error)325 ValueObjectVariable::SetValueFromCString (const char *value_str, Error& error)
326 {
327 if (m_resolved_value.GetContextType() == Value::eContextTypeRegisterInfo)
328 {
329 RegisterInfo *reg_info = m_resolved_value.GetRegisterInfo();
330 ExecutionContext exe_ctx(GetExecutionContextRef());
331 RegisterContext *reg_ctx = exe_ctx.GetRegisterContext();
332 RegisterValue reg_value;
333 if (!reg_info || !reg_ctx)
334 {
335 error.SetErrorString("unable to retrieve register info");
336 return false;
337 }
338 error = reg_value.SetValueFromCString(reg_info, value_str);
339 if (error.Fail())
340 return false;
341 if (reg_ctx->WriteRegister (reg_info, reg_value))
342 {
343 SetNeedsUpdate();
344 return true;
345 }
346 else
347 {
348 error.SetErrorString("unable to write back to register");
349 return false;
350 }
351 }
352 else
353 return ValueObject::SetValueFromCString(value_str, error);
354 }
355
356 bool
SetData(DataExtractor & data,Error & error)357 ValueObjectVariable::SetData (DataExtractor &data, Error &error)
358 {
359 if (m_resolved_value.GetContextType() == Value::eContextTypeRegisterInfo)
360 {
361 RegisterInfo *reg_info = m_resolved_value.GetRegisterInfo();
362 ExecutionContext exe_ctx(GetExecutionContextRef());
363 RegisterContext *reg_ctx = exe_ctx.GetRegisterContext();
364 RegisterValue reg_value;
365 if (!reg_info || !reg_ctx)
366 {
367 error.SetErrorString("unable to retrieve register info");
368 return false;
369 }
370 error = reg_value.SetValueFromData(reg_info, data, 0, false);
371 if (error.Fail())
372 return false;
373 if (reg_ctx->WriteRegister (reg_info, reg_value))
374 {
375 SetNeedsUpdate();
376 return true;
377 }
378 else
379 {
380 error.SetErrorString("unable to write back to register");
381 return false;
382 }
383 }
384 else
385 return ValueObject::SetData(data, error);
386 }
387