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/ValueObjectList.h"
19 #include "lldb/Core/Value.h"
20 
21 #include "lldb/Symbol/ObjectFile.h"
22 #include "lldb/Symbol/SymbolContext.h"
23 #include "lldb/Symbol/Type.h"
24 #include "lldb/Symbol/Variable.h"
25 
26 #include "lldb/Target/ExecutionContext.h"
27 #include "lldb/Target/Process.h"
28 #include "lldb/Target/RegisterContext.h"
29 #include "lldb/Target/Target.h"
30 #include "lldb/Target/Thread.h"
31 
32 
33 using namespace lldb_private;
34 
35 ValueObjectVariable::ValueObjectVariable (lldb::VariableSP &var_sp) :
36     ValueObject(),
37     m_variable_sp(var_sp)
38 {
39     // Do not attempt to construct one of these objects with no variable!
40     assert (m_variable_sp.get() != NULL);
41     m_name = var_sp->GetName();
42 }
43 
44 ValueObjectVariable::~ValueObjectVariable()
45 {
46 }
47 
48 void *
49 ValueObjectVariable::GetOpaqueClangQualType ()
50 {
51     Type *var_type = m_variable_sp->GetType();
52     if (var_type)
53         return var_type->GetOpaqueClangQualType();
54     return NULL;
55 }
56 
57 ConstString
58 ValueObjectVariable::GetTypeName()
59 {
60     Type * var_type = m_variable_sp->GetType();
61     if (var_type)
62         return var_type->GetName();
63     ConstString empty_type_name;
64     return empty_type_name;
65 }
66 
67 uint32_t
68 ValueObjectVariable::CalculateNumChildren()
69 {
70     Type *var_type = m_variable_sp->GetType();
71     if (var_type)
72         return var_type->GetNumChildren(true);
73     return 0;
74 }
75 
76 clang::ASTContext *
77 ValueObjectVariable::GetClangAST ()
78 {
79     return m_variable_sp->GetType()->GetClangAST();
80 }
81 
82 size_t
83 ValueObjectVariable::GetByteSize()
84 {
85     return m_variable_sp->GetType()->GetByteSize();
86 }
87 
88 lldb::ValueType
89 ValueObjectVariable::GetValueType() const
90 {
91     if (m_variable_sp)
92         return m_variable_sp->GetScope();
93     return lldb::eValueTypeInvalid;
94 }
95 
96 
97 
98 void
99 ValueObjectVariable::UpdateValue (ExecutionContextScope *exe_scope)
100 {
101     SetValueIsValid (false);
102     m_error.Clear();
103 
104     Variable *variable = m_variable_sp.get();
105     DWARFExpression &expr = variable->LocationExpression();
106     Value old_value(m_value);
107     ExecutionContext exe_ctx (exe_scope);
108     if (expr.Evaluate (&exe_ctx, GetClangAST(), NULL, m_value, &m_error))
109     {
110         m_value.SetContext(Value::eContextTypeDCVariable, variable);
111 
112         Value::ValueType value_type = m_value.GetValueType();
113 
114         switch (value_type)
115         {
116         default:
117             assert(!"Unhandled expression result value kind...");
118             break;
119 
120         case Value::eValueTypeScalar:
121             // The variable value is in the Scalar value inside the m_value.
122             // We can point our m_data right to it.
123             m_error = m_value.GetValueAsData (&exe_ctx, GetClangAST(), m_data, 0);
124             break;
125 
126         case Value::eValueTypeFileAddress:
127         case Value::eValueTypeLoadAddress:
128         case Value::eValueTypeHostAddress:
129             // The DWARF expression result was an address in the inferior
130             // process. If this variable is an aggregate type, we just need
131             // the address as the main value as all child variable objects
132             // will rely upon this location and add an offset and then read
133             // their own values as needed. If this variable is a simple
134             // type, we read all data for it into m_data.
135             // Make sure this type has a value before we try and read it
136             if (ClangASTContext::IsAggregateType (GetOpaqueClangQualType()))
137             {
138                 // this value object represents an aggregate type whose
139                 // children have values, but this object does not. So we
140                 // say we are changed if our location has changed.
141                 SetValueDidChange (value_type != old_value.GetValueType() || m_value.GetScalar() != old_value.GetScalar());
142             }
143             else
144             {
145                 // Copy the Value and set the context to use our Variable
146                 // so it can extract read its value into m_data appropriately
147                 Value value(m_value);
148                 value.SetContext(Value::eContextTypeDCVariable, variable);
149                 m_error = value.GetValueAsData(&exe_ctx, GetClangAST(), m_data, 0);
150             }
151             break;
152         }
153 
154         SetValueIsValid (m_error.Success());
155     }
156 }
157 
158 
159 
160 bool
161 ValueObjectVariable::IsInScope (StackFrame *frame)
162 {
163     return m_variable_sp->IsInScope (frame);
164 }
165 
166