1//===-- ExpressionVariable.h ------------------------------------*- C++ -*-===//
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#ifndef LLDB_EXPRESSION_EXPRESSIONVARIABLE_H
10#define LLDB_EXPRESSION_EXPRESSIONVARIABLE_H
11
12#include <memory>
13#include <optional>
14#include <vector>
15
16#include "llvm/ADT/DenseMap.h"
17
18#include "lldb/Core/ValueObject.h"
19#include "lldb/Utility/ConstString.h"
20#include "lldb/lldb-public.h"
21#include "llvm/Support/ExtensibleRTTI.h"
22
23namespace lldb_private {
24
25class ExpressionVariable
26 : public std::enable_shared_from_this<ExpressionVariable>,
27 public llvm::RTTIExtends<ExpressionVariable, llvm::RTTIRoot> {
28public:
29 /// LLVM RTTI support
30 static char ID;
31
32 ExpressionVariable();
33
34 virtual ~ExpressionVariable() = default;
35
36 std::optional<uint64_t> GetByteSize() { return m_frozen_sp->GetByteSize(); }
37
38 ConstString GetName() { return m_frozen_sp->GetName(); }
39
40 lldb::ValueObjectSP GetValueObject() { return m_frozen_sp; }
41
42 uint8_t *GetValueBytes();
43
44 void ValueUpdated() { m_frozen_sp->ValueUpdated(); }
45
46 RegisterInfo *GetRegisterInfo() {
47 return m_frozen_sp->GetValue().GetRegisterInfo();
48 }
49
50 void SetRegisterInfo(const RegisterInfo *reg_info) {
51 return m_frozen_sp->GetValue().SetContext(
52 context_type: Value::ContextType::RegisterInfo, p: const_cast<RegisterInfo *>(reg_info));
53 }
54
55 CompilerType GetCompilerType() { return m_frozen_sp->GetCompilerType(); }
56
57 void SetCompilerType(const CompilerType &compiler_type) {
58 m_frozen_sp->GetValue().SetCompilerType(compiler_type);
59 }
60
61 void SetName(ConstString name) { m_frozen_sp->SetName(name); }
62
63 // this function is used to copy the address-of m_live_sp into m_frozen_sp
64 // this is necessary because the results of certain cast and pointer-
65 // arithmetic operations (such as those described in bugzilla issues 11588
66 // and 11618) generate frozen objects that do not have a valid address-of,
67 // which can be troublesome when using synthetic children providers.
68 // Transferring the address-of the live object solves these issues and
69 // provides the expected user-level behavior
70 void TransferAddress(bool force = false) {
71 if (m_live_sp.get() == nullptr)
72 return;
73
74 if (m_frozen_sp.get() == nullptr)
75 return;
76
77 if (force || (m_frozen_sp->GetLiveAddress() == LLDB_INVALID_ADDRESS))
78 m_frozen_sp->SetLiveAddress(addr: m_live_sp->GetLiveAddress());
79 }
80
81 enum Flags {
82 EVNone = 0,
83 EVIsLLDBAllocated = 1 << 0, ///< This variable is resident in a location
84 ///specifically allocated for it by LLDB in the
85 ///target process
86 EVIsProgramReference = 1 << 1, ///< This variable is a reference to a
87 ///(possibly invalid) area managed by the
88 ///target program
89 EVNeedsAllocation = 1 << 2, ///< Space for this variable has yet to be
90 ///allocated in the target process
91 EVIsFreezeDried = 1 << 3, ///< This variable's authoritative version is in
92 ///m_frozen_sp (for example, for
93 ///statically-computed results)
94 EVNeedsFreezeDry =
95 1 << 4, ///< Copy from m_live_sp to m_frozen_sp during dematerialization
96 EVKeepInTarget = 1 << 5, ///< Keep the allocation after the expression is
97 ///complete rather than freeze drying its contents
98 ///and freeing it
99 EVTypeIsReference = 1 << 6, ///< The original type of this variable is a
100 ///reference, so materialize the value rather
101 ///than the location
102 EVBareRegister = 1 << 7 ///< This variable is a direct reference to $pc or
103 ///some other entity.
104 };
105
106 typedef uint16_t FlagType;
107
108 FlagType m_flags; // takes elements of Flags
109
110 // these should be private
111 lldb::ValueObjectSP m_frozen_sp;
112 lldb::ValueObjectSP m_live_sp;
113};
114
115/// \class ExpressionVariableList ExpressionVariable.h
116/// "lldb/Expression/ExpressionVariable.h"
117/// A list of variable references.
118///
119/// This class stores variables internally, acting as the permanent store.
120class ExpressionVariableList {
121public:
122 /// Implementation of methods in ExpressionVariableListBase
123 size_t GetSize() { return m_variables.size(); }
124
125 lldb::ExpressionVariableSP GetVariableAtIndex(size_t index) {
126 lldb::ExpressionVariableSP var_sp;
127 if (index < m_variables.size())
128 var_sp = m_variables[index];
129 return var_sp;
130 }
131
132 size_t AddVariable(const lldb::ExpressionVariableSP &var_sp) {
133 m_variables.push_back(x: var_sp);
134 return m_variables.size() - 1;
135 }
136
137 lldb::ExpressionVariableSP
138 AddNewlyConstructedVariable(ExpressionVariable *var) {
139 lldb::ExpressionVariableSP var_sp(var);
140 m_variables.push_back(x: var_sp);
141 return m_variables.back();
142 }
143
144 bool ContainsVariable(const lldb::ExpressionVariableSP &var_sp) {
145 const size_t size = m_variables.size();
146 for (size_t index = 0; index < size; ++index) {
147 if (m_variables[index].get() == var_sp.get())
148 return true;
149 }
150 return false;
151 }
152
153 /// Finds a variable by name in the list.
154 ///
155 /// \param[in] name
156 /// The name of the requested variable.
157 ///
158 /// \return
159 /// The variable requested, or nullptr if that variable is not in the
160 /// list.
161 lldb::ExpressionVariableSP GetVariable(ConstString name) {
162 lldb::ExpressionVariableSP var_sp;
163 for (size_t index = 0, size = GetSize(); index < size; ++index) {
164 var_sp = GetVariableAtIndex(index);
165 if (var_sp->GetName() == name)
166 return var_sp;
167 }
168 var_sp.reset();
169 return var_sp;
170 }
171
172 lldb::ExpressionVariableSP GetVariable(llvm::StringRef name) {
173 if (name.empty())
174 return nullptr;
175
176 for (size_t index = 0, size = GetSize(); index < size; ++index) {
177 auto var_sp = GetVariableAtIndex(index);
178 llvm::StringRef var_name_str = var_sp->GetName().GetStringRef();
179 if (var_name_str == name)
180 return var_sp;
181 }
182 return nullptr;
183 }
184
185 void RemoveVariable(lldb::ExpressionVariableSP var_sp) {
186 for (std::vector<lldb::ExpressionVariableSP>::iterator
187 vi = m_variables.begin(),
188 ve = m_variables.end();
189 vi != ve; ++vi) {
190 if (vi->get() == var_sp.get()) {
191 m_variables.erase(position: vi);
192 return;
193 }
194 }
195 }
196
197 void Clear() { m_variables.clear(); }
198
199private:
200 std::vector<lldb::ExpressionVariableSP> m_variables;
201};
202
203class PersistentExpressionState
204 : public ExpressionVariableList,
205 public llvm::RTTIExtends<PersistentExpressionState, llvm::RTTIRoot> {
206public:
207 /// LLVM RTTI support
208 static char ID;
209
210 PersistentExpressionState();
211
212 virtual ~PersistentExpressionState();
213
214 virtual lldb::ExpressionVariableSP
215 CreatePersistentVariable(const lldb::ValueObjectSP &valobj_sp) = 0;
216
217 virtual lldb::ExpressionVariableSP
218 CreatePersistentVariable(ExecutionContextScope *exe_scope,
219 ConstString name, const CompilerType &type,
220 lldb::ByteOrder byte_order,
221 uint32_t addr_byte_size) = 0;
222
223 /// Return a new persistent variable name with the specified prefix.
224 virtual ConstString GetNextPersistentVariableName(bool is_error = false) = 0;
225
226 virtual void
227 RemovePersistentVariable(lldb::ExpressionVariableSP variable) = 0;
228
229 virtual std::optional<CompilerType>
230 GetCompilerTypeFromPersistentDecl(ConstString type_name) = 0;
231
232 virtual lldb::addr_t LookupSymbol(ConstString name);
233
234 void RegisterExecutionUnit(lldb::IRExecutionUnitSP &execution_unit_sp);
235
236protected:
237 virtual llvm::StringRef
238 GetPersistentVariablePrefix(bool is_error = false) const = 0;
239
240private:
241 typedef std::set<lldb::IRExecutionUnitSP> ExecutionUnitSet;
242 ExecutionUnitSet
243 m_execution_units; ///< The execution units that contain valuable symbols.
244
245 typedef llvm::DenseMap<const char *, lldb::addr_t> SymbolMap;
246 SymbolMap
247 m_symbol_map; ///< The addresses of the symbols in m_execution_units.
248};
249
250} // namespace lldb_private
251
252#endif // LLDB_EXPRESSION_EXPRESSIONVARIABLE_H
253

source code of lldb/include/lldb/Expression/ExpressionVariable.h