1//===-- ValueObjectMemory.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 "lldb/Core/ValueObjectMemory.h"
10#include "lldb/Core/Value.h"
11#include "lldb/Core/ValueObject.h"
12#include "lldb/Symbol/Type.h"
13#include "lldb/Target/ExecutionContext.h"
14#include "lldb/Target/Target.h"
15#include "lldb/Utility/DataExtractor.h"
16#include "lldb/Utility/Scalar.h"
17#include "lldb/Utility/Status.h"
18#include "lldb/lldb-types.h"
19#include "llvm/Support/ErrorHandling.h"
20
21#include <assert.h>
22#include <memory>
23
24namespace lldb_private {
25class ExecutionContextScope;
26}
27
28using namespace lldb;
29using namespace lldb_private;
30
31ValueObjectSP ValueObjectMemory::Create(ExecutionContextScope *exe_scope,
32 llvm::StringRef name,
33 const Address &address,
34 lldb::TypeSP &type_sp) {
35 auto manager_sp = ValueObjectManager::Create();
36 return (new ValueObjectMemory(exe_scope, *manager_sp, name, address, type_sp))
37 ->GetSP();
38}
39
40ValueObjectSP ValueObjectMemory::Create(ExecutionContextScope *exe_scope,
41 llvm::StringRef name,
42 const Address &address,
43 const CompilerType &ast_type) {
44 auto manager_sp = ValueObjectManager::Create();
45 return (new ValueObjectMemory(exe_scope, *manager_sp, name, address,
46 ast_type))
47 ->GetSP();
48}
49
50ValueObjectMemory::ValueObjectMemory(ExecutionContextScope *exe_scope,
51 ValueObjectManager &manager,
52 llvm::StringRef name,
53 const Address &address,
54 lldb::TypeSP &type_sp)
55 : ValueObject(exe_scope, manager), m_address(address), m_type_sp(type_sp),
56 m_compiler_type() {
57 // Do not attempt to construct one of these objects with no variable!
58 assert(m_type_sp.get() != nullptr);
59 SetName(ConstString(name));
60 m_value.SetContext(Value::ContextType::LLDBType, m_type_sp.get());
61 TargetSP target_sp(GetTargetSP());
62 lldb::addr_t load_address = m_address.GetLoadAddress(target_sp.get());
63 if (load_address != LLDB_INVALID_ADDRESS) {
64 m_value.SetValueType(Value::ValueType::LoadAddress);
65 m_value.GetScalar() = load_address;
66 } else {
67 lldb::addr_t file_address = m_address.GetFileAddress();
68 if (file_address != LLDB_INVALID_ADDRESS) {
69 m_value.SetValueType(Value::ValueType::FileAddress);
70 m_value.GetScalar() = file_address;
71 } else {
72 m_value.GetScalar() = m_address.GetOffset();
73 m_value.SetValueType(Value::ValueType::Scalar);
74 }
75 }
76}
77
78ValueObjectMemory::ValueObjectMemory(ExecutionContextScope *exe_scope,
79 ValueObjectManager &manager,
80 llvm::StringRef name,
81 const Address &address,
82 const CompilerType &ast_type)
83 : ValueObject(exe_scope, manager), m_address(address), m_type_sp(),
84 m_compiler_type(ast_type) {
85 // Do not attempt to construct one of these objects with no variable!
86 assert(m_compiler_type.GetTypeSystem());
87 assert(m_compiler_type.GetOpaqueQualType());
88
89 TargetSP target_sp(GetTargetSP());
90
91 SetName(ConstString(name));
92 m_value.SetCompilerType(m_compiler_type);
93 lldb::addr_t load_address = m_address.GetLoadAddress(target_sp.get());
94 if (load_address != LLDB_INVALID_ADDRESS) {
95 m_value.SetValueType(Value::ValueType::LoadAddress);
96 m_value.GetScalar() = load_address;
97 } else {
98 lldb::addr_t file_address = m_address.GetFileAddress();
99 if (file_address != LLDB_INVALID_ADDRESS) {
100 m_value.SetValueType(Value::ValueType::FileAddress);
101 m_value.GetScalar() = file_address;
102 } else {
103 m_value.GetScalar() = m_address.GetOffset();
104 m_value.SetValueType(Value::ValueType::Scalar);
105 }
106 }
107}
108
109ValueObjectMemory::~ValueObjectMemory() {}
110
111CompilerType ValueObjectMemory::GetCompilerTypeImpl() {
112 if (m_type_sp)
113 return m_type_sp->GetForwardCompilerType();
114 return m_compiler_type;
115}
116
117ConstString ValueObjectMemory::GetTypeName() {
118 if (m_type_sp)
119 return m_type_sp->GetName();
120 return m_compiler_type.GetTypeName();
121}
122
123ConstString ValueObjectMemory::GetDisplayTypeName() {
124 if (m_type_sp)
125 return m_type_sp->GetForwardCompilerType().GetDisplayTypeName();
126 return m_compiler_type.GetDisplayTypeName();
127}
128
129size_t ValueObjectMemory::CalculateNumChildren(uint32_t max) {
130 if (m_type_sp) {
131 auto child_count = m_type_sp->GetNumChildren(true);
132 return child_count <= max ? child_count : max;
133 }
134
135 ExecutionContext exe_ctx(GetExecutionContextRef());
136 const bool omit_empty_base_classes = true;
137 auto child_count =
138 m_compiler_type.GetNumChildren(omit_empty_base_classes, &exe_ctx);
139 return child_count <= max ? child_count : max;
140}
141
142llvm::Optional<uint64_t> ValueObjectMemory::GetByteSize() {
143 ExecutionContext exe_ctx(GetExecutionContextRef());
144 if (m_type_sp)
145 return m_type_sp->GetByteSize(exe_ctx.GetBestExecutionContextScope());
146 return m_compiler_type.GetByteSize(exe_ctx.GetBestExecutionContextScope());
147}
148
149lldb::ValueType ValueObjectMemory::GetValueType() const {
150 // RETHINK: Should this be inherited from somewhere?
151 return lldb::eValueTypeVariableGlobal;
152}
153
154bool ValueObjectMemory::UpdateValue() {
155 SetValueIsValid(false);
156 m_error.Clear();
157
158 ExecutionContext exe_ctx(GetExecutionContextRef());
159
160 Target *target = exe_ctx.GetTargetPtr();
161 if (target) {
162 m_data.SetByteOrder(target->GetArchitecture().GetByteOrder());
163 m_data.SetAddressByteSize(target->GetArchitecture().GetAddressByteSize());
164 }
165
166 Value old_value(m_value);
167 if (m_address.IsValid()) {
168 Value::ValueType value_type = m_value.GetValueType();
169
170 switch (value_type) {
171 case Value::ValueType::Invalid:
172 m_error.SetErrorString("Invalid value");
173 return false;
174 case Value::ValueType::Scalar:
175 // The variable value is in the Scalar value inside the m_value. We can
176 // point our m_data right to it.
177 m_error = m_value.GetValueAsData(&exe_ctx, m_data, GetModule().get());
178 break;
179
180 case Value::ValueType::FileAddress:
181 case Value::ValueType::LoadAddress:
182 case Value::ValueType::HostAddress:
183 // The DWARF expression result was an address in the inferior process. If
184 // this variable is an aggregate type, we just need the address as the
185 // main value as all child variable objects will rely upon this location
186 // and add an offset and then read their own values as needed. If this
187 // variable is a simple type, we read all data for it into m_data. Make
188 // sure this type has a value before we try and read it
189
190 // If we have a file address, convert it to a load address if we can.
191 if (value_type == Value::ValueType::FileAddress &&
192 exe_ctx.GetProcessPtr()) {
193 lldb::addr_t load_addr = m_address.GetLoadAddress(target);
194 if (load_addr != LLDB_INVALID_ADDRESS) {
195 m_value.SetValueType(Value::ValueType::LoadAddress);
196 m_value.GetScalar() = load_addr;
197 }
198 }
199
200 if (!CanProvideValue()) {
201 // this value object represents an aggregate type whose children have
202 // values, but this object does not. So we say we are changed if our
203 // location has changed.
204 SetValueDidChange(value_type != old_value.GetValueType() ||
205 m_value.GetScalar() != old_value.GetScalar());
206 } else {
207 // Copy the Value and set the context to use our Variable so it can
208 // extract read its value into m_data appropriately
209 Value value(m_value);
210 if (m_type_sp)
211 value.SetContext(Value::ContextType::LLDBType, m_type_sp.get());
212 else {
213 value.SetCompilerType(m_compiler_type);
214 }
215
216 m_error = value.GetValueAsData(&exe_ctx, m_data, GetModule().get());
217 }
218 break;
219 }
220
221 SetValueIsValid(m_error.Success());
222 }
223 return m_error.Success();
224}
225
226bool ValueObjectMemory::IsInScope() {
227 // FIXME: Maybe try to read the memory address, and if that works, then
228 // we are in scope?
229 return true;
230}
231
232lldb::ModuleSP ValueObjectMemory::GetModule() { return m_address.GetModule(); }
233