1 //===-- ValueObjectRegister.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/ValueObject/ValueObjectRegister.h"
10
11 #include "lldb/Core/Module.h"
12 #include "lldb/Core/Value.h"
13 #include "lldb/Symbol/CompilerType.h"
14 #include "lldb/Symbol/TypeSystem.h"
15 #include "lldb/Target/ExecutionContext.h"
16 #include "lldb/Target/Process.h"
17 #include "lldb/Target/RegisterContext.h"
18 #include "lldb/Target/StackFrame.h"
19 #include "lldb/Target/Target.h"
20 #include "lldb/Utility/DataExtractor.h"
21 #include "lldb/Utility/LLDBLog.h"
22 #include "lldb/Utility/Log.h"
23 #include "lldb/Utility/Scalar.h"
24 #include "lldb/Utility/Status.h"
25 #include "lldb/Utility/Stream.h"
26
27 #include "llvm/ADT/StringRef.h"
28
29 #include <cassert>
30 #include <memory>
31 #include <optional>
32
33 namespace lldb_private {
34 class ExecutionContextScope;
35 }
36
37 using namespace lldb;
38 using namespace lldb_private;
39
40 #pragma mark ValueObjectRegisterSet
41
42 ValueObjectSP
Create(ExecutionContextScope * exe_scope,lldb::RegisterContextSP & reg_ctx_sp,uint32_t set_idx)43 ValueObjectRegisterSet::Create(ExecutionContextScope *exe_scope,
44 lldb::RegisterContextSP ®_ctx_sp,
45 uint32_t set_idx) {
46 auto manager_sp = ValueObjectManager::Create();
47 return (new ValueObjectRegisterSet(exe_scope, *manager_sp, reg_ctx_sp,
48 set_idx))
49 ->GetSP();
50 }
51
ValueObjectRegisterSet(ExecutionContextScope * exe_scope,ValueObjectManager & manager,lldb::RegisterContextSP & reg_ctx,uint32_t reg_set_idx)52 ValueObjectRegisterSet::ValueObjectRegisterSet(ExecutionContextScope *exe_scope,
53 ValueObjectManager &manager,
54 lldb::RegisterContextSP ®_ctx,
55 uint32_t reg_set_idx)
56 : ValueObject(exe_scope, manager), m_reg_ctx_sp(reg_ctx),
57 m_reg_set(nullptr), m_reg_set_idx(reg_set_idx) {
58 assert(reg_ctx);
59 m_reg_set = reg_ctx->GetRegisterSet(m_reg_set_idx);
60 if (m_reg_set) {
61 m_name.SetCString(m_reg_set->name);
62 }
63 }
64
65 ValueObjectRegisterSet::~ValueObjectRegisterSet() = default;
66
GetCompilerTypeImpl()67 CompilerType ValueObjectRegisterSet::GetCompilerTypeImpl() {
68 return CompilerType();
69 }
70
GetTypeName()71 ConstString ValueObjectRegisterSet::GetTypeName() { return ConstString(); }
72
GetQualifiedTypeName()73 ConstString ValueObjectRegisterSet::GetQualifiedTypeName() {
74 return ConstString();
75 }
76
77 llvm::Expected<uint32_t>
CalculateNumChildren(uint32_t max)78 ValueObjectRegisterSet::CalculateNumChildren(uint32_t max) {
79 const RegisterSet *reg_set = m_reg_ctx_sp->GetRegisterSet(m_reg_set_idx);
80 if (reg_set) {
81 auto reg_count = reg_set->num_registers;
82 return reg_count <= max ? reg_count : max;
83 }
84 return 0;
85 }
86
GetByteSize()87 llvm::Expected<uint64_t> ValueObjectRegisterSet::GetByteSize() { return 0; }
88
UpdateValue()89 bool ValueObjectRegisterSet::UpdateValue() {
90 m_error.Clear();
91 SetValueDidChange(false);
92 ExecutionContext exe_ctx(GetExecutionContextRef());
93 StackFrame *frame = exe_ctx.GetFramePtr();
94 if (frame == nullptr)
95 m_reg_ctx_sp.reset();
96 else {
97 m_reg_ctx_sp = frame->GetRegisterContext();
98 if (m_reg_ctx_sp) {
99 const RegisterSet *reg_set = m_reg_ctx_sp->GetRegisterSet(m_reg_set_idx);
100 if (reg_set == nullptr)
101 m_reg_ctx_sp.reset();
102 else if (m_reg_set != reg_set) {
103 SetValueDidChange(true);
104 m_name.SetCString(reg_set->name);
105 }
106 }
107 }
108 if (m_reg_ctx_sp) {
109 SetValueIsValid(true);
110 } else {
111 SetValueIsValid(false);
112 m_error = Status::FromErrorString("no register context");
113 m_children.Clear();
114 }
115 return m_error.Success();
116 }
117
CreateChildAtIndex(size_t idx)118 ValueObject *ValueObjectRegisterSet::CreateChildAtIndex(size_t idx) {
119 if (m_reg_ctx_sp && m_reg_set) {
120 return new ValueObjectRegister(
121 *this, m_reg_ctx_sp,
122 m_reg_ctx_sp->GetRegisterInfoAtIndex(m_reg_set->registers[idx]));
123 }
124 return nullptr;
125 }
126
127 lldb::ValueObjectSP
GetChildMemberWithName(llvm::StringRef name,bool can_create)128 ValueObjectRegisterSet::GetChildMemberWithName(llvm::StringRef name,
129 bool can_create) {
130 ValueObject *valobj = nullptr;
131 if (m_reg_ctx_sp && m_reg_set) {
132 const RegisterInfo *reg_info = m_reg_ctx_sp->GetRegisterInfoByName(name);
133 if (reg_info != nullptr)
134 valobj = new ValueObjectRegister(*this, m_reg_ctx_sp, reg_info);
135 }
136 if (valobj)
137 return valobj->GetSP();
138 else
139 return ValueObjectSP();
140 }
141
142 llvm::Expected<size_t>
GetIndexOfChildWithName(llvm::StringRef name)143 ValueObjectRegisterSet::GetIndexOfChildWithName(llvm::StringRef name) {
144 if (m_reg_ctx_sp && m_reg_set) {
145 const RegisterInfo *reg_info = m_reg_ctx_sp->GetRegisterInfoByName(name);
146 if (reg_info != nullptr)
147 return reg_info->kinds[eRegisterKindLLDB];
148 }
149 return llvm::createStringError("Type has no child named '%s'",
150 name.str().c_str());
151 }
152
153 #pragma mark -
154 #pragma mark ValueObjectRegister
155
ConstructObject(const RegisterInfo * reg_info)156 void ValueObjectRegister::ConstructObject(const RegisterInfo *reg_info) {
157 if (reg_info) {
158 m_reg_info = *reg_info;
159 if (reg_info->name)
160 m_name.SetCString(reg_info->name);
161 else if (reg_info->alt_name)
162 m_name.SetCString(reg_info->alt_name);
163 }
164 }
165
ValueObjectRegister(ValueObject & parent,lldb::RegisterContextSP & reg_ctx_sp,const RegisterInfo * reg_info)166 ValueObjectRegister::ValueObjectRegister(ValueObject &parent,
167 lldb::RegisterContextSP ®_ctx_sp,
168 const RegisterInfo *reg_info)
169 : ValueObject(parent), m_reg_ctx_sp(reg_ctx_sp), m_reg_info(),
170 m_reg_value(), m_type_name(), m_compiler_type() {
171 assert(reg_ctx_sp.get());
172 ConstructObject(reg_info);
173 }
174
Create(ExecutionContextScope * exe_scope,lldb::RegisterContextSP & reg_ctx_sp,const RegisterInfo * reg_info)175 ValueObjectSP ValueObjectRegister::Create(ExecutionContextScope *exe_scope,
176 lldb::RegisterContextSP ®_ctx_sp,
177 const RegisterInfo *reg_info) {
178 auto manager_sp = ValueObjectManager::Create();
179 return (new ValueObjectRegister(exe_scope, *manager_sp, reg_ctx_sp, reg_info))
180 ->GetSP();
181 }
182
ValueObjectRegister(ExecutionContextScope * exe_scope,ValueObjectManager & manager,lldb::RegisterContextSP & reg_ctx,const RegisterInfo * reg_info)183 ValueObjectRegister::ValueObjectRegister(ExecutionContextScope *exe_scope,
184 ValueObjectManager &manager,
185 lldb::RegisterContextSP ®_ctx,
186 const RegisterInfo *reg_info)
187 : ValueObject(exe_scope, manager), m_reg_ctx_sp(reg_ctx), m_reg_info(),
188 m_reg_value(), m_type_name(), m_compiler_type() {
189 assert(reg_ctx);
190 ConstructObject(reg_info);
191 }
192
193 ValueObjectRegister::~ValueObjectRegister() = default;
194
GetCompilerTypeImpl()195 CompilerType ValueObjectRegister::GetCompilerTypeImpl() {
196 if (!m_compiler_type.IsValid()) {
197 ExecutionContext exe_ctx(GetExecutionContextRef());
198 if (auto *target = exe_ctx.GetTargetPtr()) {
199 if (auto *exe_module = target->GetExecutableModulePointer()) {
200 auto type_system_or_err =
201 exe_module->GetTypeSystemForLanguage(eLanguageTypeC);
202 if (auto err = type_system_or_err.takeError()) {
203 LLDB_LOG_ERROR(GetLog(LLDBLog::Types), std::move(err),
204 "Unable to get CompilerType from TypeSystem: {0}");
205 } else {
206 if (auto ts = *type_system_or_err)
207 m_compiler_type = ts->GetBuiltinTypeForEncodingAndBitSize(
208 m_reg_info.encoding, m_reg_info.byte_size * 8);
209 }
210 }
211 }
212 }
213 return m_compiler_type;
214 }
215
GetTypeName()216 ConstString ValueObjectRegister::GetTypeName() {
217 if (m_type_name.IsEmpty())
218 m_type_name = GetCompilerType().GetTypeName();
219 return m_type_name;
220 }
221
222 llvm::Expected<uint32_t>
CalculateNumChildren(uint32_t max)223 ValueObjectRegister::CalculateNumChildren(uint32_t max) {
224 ExecutionContext exe_ctx(GetExecutionContextRef());
225 auto children_count = GetCompilerType().GetNumChildren(true, &exe_ctx);
226 if (!children_count)
227 return children_count;
228 return *children_count <= max ? *children_count : max;
229 }
230
GetByteSize()231 llvm::Expected<uint64_t> ValueObjectRegister::GetByteSize() {
232 return m_reg_info.byte_size;
233 }
234
UpdateValue()235 bool ValueObjectRegister::UpdateValue() {
236 m_error.Clear();
237 ExecutionContext exe_ctx(GetExecutionContextRef());
238 StackFrame *frame = exe_ctx.GetFramePtr();
239 if (frame == nullptr) {
240 m_reg_ctx_sp.reset();
241 m_reg_value.Clear();
242 }
243
244 if (m_reg_ctx_sp) {
245 RegisterValue m_old_reg_value(m_reg_value);
246 if (m_reg_ctx_sp->ReadRegister(&m_reg_info, m_reg_value)) {
247 if (m_reg_value.GetData(m_data)) {
248 Process *process = exe_ctx.GetProcessPtr();
249 if (process)
250 m_data.SetAddressByteSize(process->GetAddressByteSize());
251 m_value.SetContext(Value::ContextType::RegisterInfo,
252 (void *)&m_reg_info);
253 m_value.SetValueType(Value::ValueType::HostAddress);
254 m_value.GetScalar() = (uintptr_t)m_data.GetDataStart();
255 SetValueIsValid(true);
256 SetValueDidChange(!(m_old_reg_value == m_reg_value));
257 return true;
258 }
259 }
260 }
261
262 SetValueIsValid(false);
263 m_error = Status::FromErrorString("no register context");
264 return false;
265 }
266
SetValueFromCString(const char * value_str,Status & error)267 bool ValueObjectRegister::SetValueFromCString(const char *value_str,
268 Status &error) {
269 // The new value will be in the m_data. Copy that into our register value.
270 error =
271 m_reg_value.SetValueFromString(&m_reg_info, llvm::StringRef(value_str));
272 if (!error.Success())
273 return false;
274
275 if (!m_reg_ctx_sp->WriteRegister(&m_reg_info, m_reg_value)) {
276 error = Status::FromErrorString("unable to write back to register");
277 return false;
278 }
279
280 SetNeedsUpdate();
281 return true;
282 }
283
SetData(DataExtractor & data,Status & error)284 bool ValueObjectRegister::SetData(DataExtractor &data, Status &error) {
285 error = m_reg_value.SetValueFromData(m_reg_info, data, 0, false);
286 if (!error.Success())
287 return false;
288
289 if (!m_reg_ctx_sp->WriteRegister(&m_reg_info, m_reg_value)) {
290 error = Status::FromErrorString("unable to write back to register");
291 return false;
292 }
293
294 SetNeedsUpdate();
295 return true;
296 }
297
ResolveValue(Scalar & scalar)298 bool ValueObjectRegister::ResolveValue(Scalar &scalar) {
299 if (UpdateValueIfNeeded(
300 false)) // make sure that you are up to date before returning anything
301 return m_reg_value.GetScalarValue(scalar);
302 return false;
303 }
304
GetExpressionPath(Stream & s,GetExpressionPathFormat epformat)305 void ValueObjectRegister::GetExpressionPath(Stream &s,
306 GetExpressionPathFormat epformat) {
307 s.Printf("$%s", m_reg_info.name);
308 }
309