1 //===-- ValueObjectDynamicValue.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/ValueObjectDynamicValue.h"
12 
13 // C Includes
14 // C++ Includes
15 // Other libraries and framework includes
16 // Project includes
17 #include "lldb/Core/Log.h"
18 #include "lldb/Core/Module.h"
19 #include "lldb/Core/ValueObjectList.h"
20 #include "lldb/Core/Value.h"
21 #include "lldb/Core/ValueObject.h"
22 
23 #include "lldb/Symbol/ClangASTType.h"
24 #include "lldb/Symbol/ObjectFile.h"
25 #include "lldb/Symbol/SymbolContext.h"
26 #include "lldb/Symbol/Type.h"
27 #include "lldb/Symbol/Variable.h"
28 
29 #include "lldb/Target/ExecutionContext.h"
30 #include "lldb/Target/LanguageRuntime.h"
31 #include "lldb/Target/Process.h"
32 #include "lldb/Target/RegisterContext.h"
33 #include "lldb/Target/Target.h"
34 #include "lldb/Target/Thread.h"
35 
36 using namespace lldb_private;
37 
38 ValueObjectDynamicValue::ValueObjectDynamicValue (ValueObject &parent, lldb::DynamicValueType use_dynamic) :
39     ValueObject(parent),
40     m_address (),
41     m_dynamic_type_info(),
42     m_use_dynamic (use_dynamic)
43 {
44     SetName (parent.GetName());
45 }
46 
47 ValueObjectDynamicValue::~ValueObjectDynamicValue()
48 {
49     m_owning_valobj_sp.reset();
50 }
51 
52 lldb::clang_type_t
53 ValueObjectDynamicValue::GetClangTypeImpl ()
54 {
55     if (m_dynamic_type_info.HasTypeSP())
56         return m_value.GetClangType();
57     else
58         return m_parent->GetClangType();
59 }
60 
61 ConstString
62 ValueObjectDynamicValue::GetTypeName()
63 {
64     const bool success = UpdateValueIfNeeded(false);
65     if (success)
66     {
67         if (m_dynamic_type_info.HasTypeSP())
68             return ClangASTType::GetConstTypeName (GetClangAST(), GetClangType());
69         if (m_dynamic_type_info.HasName())
70             return m_dynamic_type_info.GetName();
71     }
72     return m_parent->GetTypeName();
73 }
74 
75 ConstString
76 ValueObjectDynamicValue::GetQualifiedTypeName()
77 {
78     const bool success = UpdateValueIfNeeded(false);
79     if (success)
80     {
81         if (m_dynamic_type_info.HasTypeSP())
82             return ClangASTType::GetConstQualifiedTypeName (GetClangAST(), GetClangType());
83         if (m_dynamic_type_info.HasName())
84             return m_dynamic_type_info.GetName();
85     }
86     return m_parent->GetTypeName();
87 }
88 
89 size_t
90 ValueObjectDynamicValue::CalculateNumChildren()
91 {
92     const bool success = UpdateValueIfNeeded(false);
93     if (success && m_dynamic_type_info.HasTypeSP())
94         return ClangASTContext::GetNumChildren (GetClangAST (), GetClangType(), true);
95     else
96         return m_parent->GetNumChildren();
97 }
98 
99 clang::ASTContext *
100 ValueObjectDynamicValue::GetClangASTImpl ()
101 {
102     const bool success = UpdateValueIfNeeded(false);
103     if (success && m_dynamic_type_info.HasTypeSP())
104         return m_dynamic_type_info.GetTypeSP()->GetClangAST();
105     else
106         return m_parent->GetClangAST ();
107 }
108 
109 uint64_t
110 ValueObjectDynamicValue::GetByteSize()
111 {
112     const bool success = UpdateValueIfNeeded(false);
113     if (success && m_dynamic_type_info.HasTypeSP())
114         return m_value.GetValueByteSize(GetClangAST(), NULL);
115     else
116         return m_parent->GetByteSize();
117 }
118 
119 lldb::ValueType
120 ValueObjectDynamicValue::GetValueType() const
121 {
122     return m_parent->GetValueType();
123 }
124 
125 bool
126 ValueObjectDynamicValue::UpdateValue ()
127 {
128     SetValueIsValid (false);
129     m_error.Clear();
130 
131     if (!m_parent->UpdateValueIfNeeded(false))
132     {
133         // The dynamic value failed to get an error, pass the error along
134         if (m_error.Success() && m_parent->GetError().Fail())
135             m_error = m_parent->GetError();
136         return false;
137     }
138 
139     // Setting our type_sp to NULL will route everything back through our
140     // parent which is equivalent to not using dynamic values.
141     if (m_use_dynamic == lldb::eNoDynamicValues)
142     {
143         m_dynamic_type_info.Clear();
144         return true;
145     }
146 
147     ExecutionContext exe_ctx (GetExecutionContextRef());
148     Target *target = exe_ctx.GetTargetPtr();
149     if (target)
150     {
151         m_data.SetByteOrder(target->GetArchitecture().GetByteOrder());
152         m_data.SetAddressByteSize(target->GetArchitecture().GetAddressByteSize());
153     }
154 
155     // First make sure our Type and/or Address haven't changed:
156     Process *process = exe_ctx.GetProcessPtr();
157     if (!process)
158         return false;
159 
160     TypeAndOrName class_type_or_name;
161     Address dynamic_address;
162     bool found_dynamic_type = false;
163 
164     lldb::LanguageType known_type = m_parent->GetObjectRuntimeLanguage();
165     if (known_type != lldb::eLanguageTypeUnknown && known_type != lldb::eLanguageTypeC)
166     {
167         LanguageRuntime *runtime = process->GetLanguageRuntime (known_type);
168         if (runtime)
169             found_dynamic_type = runtime->GetDynamicTypeAndAddress (*m_parent, m_use_dynamic, class_type_or_name, dynamic_address);
170     }
171     else
172     {
173         LanguageRuntime *cpp_runtime = process->GetLanguageRuntime (lldb::eLanguageTypeC_plus_plus);
174         if (cpp_runtime)
175             found_dynamic_type = cpp_runtime->GetDynamicTypeAndAddress (*m_parent, m_use_dynamic, class_type_or_name, dynamic_address);
176 
177         if (!found_dynamic_type)
178         {
179             LanguageRuntime *objc_runtime = process->GetLanguageRuntime (lldb::eLanguageTypeObjC);
180             if (objc_runtime)
181                 found_dynamic_type = objc_runtime->GetDynamicTypeAndAddress (*m_parent, m_use_dynamic, class_type_or_name, dynamic_address);
182         }
183     }
184 
185     // Getting the dynamic value may have run the program a bit, and so marked us as needing updating, but we really
186     // don't...
187 
188     m_update_point.SetUpdated();
189 
190     // If we don't have a dynamic type, then make ourselves just a echo of our parent.
191     // Or we could return false, and make ourselves an echo of our parent?
192     if (!found_dynamic_type)
193     {
194         if (m_dynamic_type_info)
195             SetValueDidChange(true);
196         ClearDynamicTypeInformation();
197         m_dynamic_type_info.Clear();
198         m_value = m_parent->GetValue();
199         m_error = m_value.GetValueAsData (&exe_ctx, GetClangAST(), m_data, 0, GetModule().get());
200         return m_error.Success();
201     }
202 
203     Value old_value(m_value);
204 
205     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_TYPES));
206 
207     bool has_changed_type = false;
208 
209     if (!m_dynamic_type_info)
210     {
211         m_dynamic_type_info = class_type_or_name;
212         has_changed_type = true;
213     }
214     else if (class_type_or_name != m_dynamic_type_info)
215     {
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)
223         ClearDynamicTypeInformation ();
224 
225     if (!m_address.IsValid() || m_address != dynamic_address)
226     {
227         if (m_address.IsValid())
228             SetValueDidChange (true);
229 
230         // We've moved, so we should be fine...
231         m_address = dynamic_address;
232         lldb::TargetSP target_sp (GetTargetSP());
233         lldb::addr_t load_address = m_address.GetLoadAddress(target_sp.get());
234         m_value.GetScalar() = load_address;
235     }
236 
237     lldb::clang_type_t corrected_type;
238     if (m_dynamic_type_info.HasTypeSP())
239     {
240         // The type will always be the type of the dynamic object.  If our parent's type was a pointer,
241         // then our type should be a pointer to the type of the dynamic object.  If a reference, then the original type
242         // should be okay...
243         lldb::clang_type_t orig_type;
244         clang::ASTContext* ast;
245         orig_type = m_dynamic_type_info.GetTypeSP()->GetClangForwardType();
246         ast = m_dynamic_type_info.GetTypeSP()->GetClangAST();
247         corrected_type = orig_type;
248         if (m_parent->IsPointerType())
249             corrected_type = ClangASTContext::CreatePointerType (ast, orig_type);
250         else if (m_parent->IsPointerOrReferenceType())
251             corrected_type = ClangASTContext::CreateLValueReferenceType (ast, orig_type);
252     }
253     else /*if (m_dynamic_type_info.HasName())*/
254     {
255         // If we are here we need to adjust our dynamic type name to include the correct & or * symbol
256         std::string type_name_buf (m_dynamic_type_info.GetName().GetCString());
257         if (m_parent->IsPointerType())
258             type_name_buf.append(" *");
259         else if (m_parent->IsPointerOrReferenceType())
260             type_name_buf.append(" &");
261         corrected_type = m_parent->GetClangType();
262         m_dynamic_type_info.SetName(type_name_buf.c_str());
263     }
264 
265     m_value.SetContext (Value::eContextTypeClangType, corrected_type);
266 
267     // Our address is the location of the dynamic type stored in memory.  It isn't a load address,
268     // because we aren't pointing to the LOCATION that stores the pointer to us, we're pointing to us...
269     m_value.SetValueType(Value::eValueTypeScalar);
270 
271     if (has_changed_type && log)
272         log->Printf("[%s %p] has a new dynamic type %s",
273                     GetName().GetCString(),
274                     this,
275                     GetTypeName().GetCString());
276 
277     if (m_address.IsValid() && m_dynamic_type_info)
278     {
279         // The variable value is in the Scalar value inside the m_value.
280         // We can point our m_data right to it.
281         m_error = m_value.GetValueAsData (&exe_ctx, GetClangAST(), m_data, 0, GetModule().get());
282         if (m_error.Success())
283         {
284             if (ClangASTContext::IsAggregateType (GetClangType()))
285             {
286                 // this value object represents an aggregate type whose
287                 // children have values, but this object does not. So we
288                 // say we are changed if our location has changed.
289                 SetValueDidChange (m_value.GetValueType() != old_value.GetValueType() || m_value.GetScalar() != old_value.GetScalar());
290             }
291 
292             SetValueIsValid (true);
293             return true;
294         }
295     }
296 
297     // We get here if we've failed above...
298     SetValueIsValid (false);
299     return false;
300 }
301 
302 
303 
304 bool
305 ValueObjectDynamicValue::IsInScope ()
306 {
307     return m_parent->IsInScope();
308 }
309 
310 bool
311 ValueObjectDynamicValue::SetValueFromCString (const char *value_str, Error& error)
312 {
313     if (!UpdateValueIfNeeded(false))
314     {
315         error.SetErrorString("unable to read value");
316         return false;
317     }
318 
319     uint64_t my_value = GetValueAsUnsigned(UINT64_MAX);
320     uint64_t parent_value = m_parent->GetValueAsUnsigned(UINT64_MAX);
321 
322     if (my_value == UINT64_MAX || parent_value == UINT64_MAX)
323     {
324         error.SetErrorString("unable to read value");
325         return false;
326     }
327 
328     // if we are at an offset from our parent, in order to set ourselves correctly we would need
329     // to change the new value so that it refers to the correct dynamic type. we choose not to deal
330     // with that - if anything more than a value overwrite is required, you should be using the
331     // expression parser instead of the value editing facility
332     if (my_value != parent_value)
333     {
334         // but NULL'ing out a value should always be allowed
335         if (strcmp(value_str,"0"))
336         {
337             error.SetErrorString("unable to modify dynamic value, use 'expression' command");
338             return false;
339         }
340     }
341 
342     bool ret_val = m_parent->SetValueFromCString(value_str,error);
343     SetNeedsUpdate();
344     return ret_val;
345 }
346