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ClangExpressionVariable.h
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1//===-- ClangExpressionVariable.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_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_CLANGEXPRESSIONVARIABLE_H
10#define LLDB_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_CLANGEXPRESSIONVARIABLE_H
11
12#include <csignal>
13#include <cstdint>
14#include <cstring>
15
16#include <map>
17#include <string>
18#include <vector>
19
20#include "llvm/Support/Casting.h"
21
22#include "lldb/Core/Value.h"
26#include "lldb/lldb-public.h"
27
28namespace llvm {
29class Value;
30}
31
32namespace clang {
33class NamedDecl;
34}
35
36namespace lldb_private {
37
38class ValueObjectConstResult;
39
40/// \class ClangExpressionVariable ClangExpressionVariable.h
41/// "lldb/Expression/ClangExpressionVariable.h" Encapsulates one variable for
42/// the expression parser.
43///
44/// The expression parser uses variables in three different contexts:
45///
46/// First, it stores persistent variables along with the process for use in
47/// expressions. These persistent variables contain their own data and are
48/// typed.
49///
50/// Second, in an interpreted expression, it stores the local variables for
51/// the expression along with the expression. These variables contain their
52/// own data and are typed.
53///
54/// Third, in a JIT-compiled expression, it stores the variables that the
55/// expression needs to have materialized and dematerialized at each
56/// execution. These do not contain their own data but are named and typed.
57///
58/// This class supports all of these use cases using simple type polymorphism,
59/// and provides necessary support methods. Its interface is RTTI-neutral.
61 : public llvm::RTTIExtends<ClangExpressionVariable, ExpressionVariable> {
62public:
63 // LLVM RTTI support
64 static char ID;
65
67 lldb::ByteOrder byte_order, uint32_t addr_byte_size);
68
70 ConstString name, uint16_t flags = EVNone);
71
73
75 ConstString name,
76 const TypeFromUser &user_type,
77 lldb::ByteOrder byte_order, uint32_t addr_byte_size);
78
79 /// Utility functions for dealing with ExpressionVariableLists in Clang-
80 /// specific ways
81
82 /// Finds a variable by NamedDecl in the list.
83 ///
84 /// \return
85 /// The variable requested, or NULL if that variable is not in the list.
87 FindVariableInList(ExpressionVariableList &list, const clang::NamedDecl *decl,
88 uint64_t parser_id) {
90 for (size_t index = 0, size = list.GetSize(); index < size; ++index) {
91 var_sp = list.GetVariableAtIndex(index);
92
93 if (ClangExpressionVariable *clang_var =
94 llvm::dyn_cast<ClangExpressionVariable>(var_sp.get())) {
96 clang_var->GetParserVars(parser_id);
97
98 if (parser_vars && parser_vars->m_named_decl == decl)
99 return clang_var;
100 }
101 }
102 return nullptr;
103 }
104
105 /// If the variable contains its own data, make a Value point at it. If \a
106 /// exe_ctx in not NULL, the value will be resolved in with that execution
107 /// context.
108 ///
109 /// \param[in] value
110 /// The value to point at the data.
111 ///
112 /// \param[in] exe_ctx
113 /// The execution context to use to resolve \a value.
114 ///
115 /// \return
116 /// True on success; false otherwise (in particular, if this variable
117 /// does not contain its own data).
119
120 /// The following values should not live beyond parsing
122 public:
123 ParserVars() = default;
124
125 const clang::NamedDecl *m_named_decl =
126 nullptr; ///< The Decl corresponding to this variable
127 llvm::Value *m_llvm_value =
128 nullptr; ///< The IR value corresponding to this variable;
129 /// usually a GlobalValue
131 m_lldb_value; ///< The value found in LLDB for this variable
132 lldb::VariableSP m_lldb_var; ///< The original variable for this variable
134 nullptr; ///< The original symbol for this
135 /// variable, if it was a symbol
136
137 /// Callback that provides a ValueObject for the
138 /// specified frame. Used by the materializer for
139 /// re-fetching ValueObjects when materializing
140 /// ivars.
142 };
143
144private:
145 typedef std::map<uint64_t, ParserVars> ParserVarMap;
147
148public:
149 /// Make this variable usable by the parser by allocating space for parser-
150 /// specific variables
151 void EnableParserVars(uint64_t parser_id) {
152 m_parser_vars.insert(std::make_pair(parser_id, ParserVars()));
153 }
154
155 /// Deallocate parser-specific variables
156 void DisableParserVars(uint64_t parser_id) { m_parser_vars.erase(parser_id); }
157
158 /// Access parser-specific variables
159 ParserVars *GetParserVars(uint64_t parser_id) {
160 ParserVarMap::iterator i = m_parser_vars.find(parser_id);
161
162 if (i == m_parser_vars.end())
163 return nullptr;
164 else
165 return &i->second;
166 }
167
168 /// The following values are valid if the variable is used by JIT code
169 struct JITVars {
170 JITVars() = default;
171
173 0; ///< The required alignment of the variable, in bytes
174 size_t m_size = 0; ///< The space required for the variable, in bytes
176 0; ///< The offset of the variable in the struct, in bytes
177 };
178
179private:
180 typedef std::map<uint64_t, JITVars> JITVarMap;
182
183public:
184 /// Make this variable usable for materializing for the JIT by allocating
185 /// space for JIT-specific variables
186 void EnableJITVars(uint64_t parser_id) {
187 m_jit_vars.insert(std::make_pair(parser_id, JITVars()));
188 }
189
190 /// Deallocate JIT-specific variables
191 void DisableJITVars(uint64_t parser_id) { m_jit_vars.erase(parser_id); }
192
193 JITVars *GetJITVars(uint64_t parser_id) {
194 JITVarMap::iterator i = m_jit_vars.find(parser_id);
195
196 if (i == m_jit_vars.end())
197 return nullptr;
198 else
199 return &i->second;
200 }
201
203
204 /// Members
208};
209
210} // namespace lldb_private
211
212#endif // LLDB_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_CLANGEXPRESSIONVARIABLE_H
The following values should not live beyond parsing.
ValueObjectProviderTy m_lldb_valobj_provider
Callback that provides a ValueObject for the specified frame.
const lldb_private::Symbol * m_lldb_sym
The original symbol for this variable, if it was a symbol.
lldb_private::Value m_lldb_value
The value found in LLDB for this variable.
lldb::VariableSP m_lldb_var
The original variable for this variable.
llvm::Value * m_llvm_value
The IR value corresponding to this variable; usually a GlobalValue.
const clang::NamedDecl * m_named_decl
The Decl corresponding to this variable.
"lldb/Expression/ClangExpressionVariable.h" Encapsulates one variable for the expression parser.
static ClangExpressionVariable * FindVariableInList(ExpressionVariableList &list, const clang::NamedDecl *decl, uint64_t parser_id)
Utility functions for dealing with ExpressionVariableLists in Clang- specific ways.
ParserVars * GetParserVars(uint64_t parser_id)
Access parser-specific variables.
bool PointValueAtData(Value &value, ExecutionContext *exe_ctx)
If the variable contains its own data, make a Value point at it.
void DisableJITVars(uint64_t parser_id)
Deallocate JIT-specific variables.
JITVars * GetJITVars(uint64_t parser_id)
const ClangExpressionVariable & operator=(const ClangExpressionVariable &)=delete
ClangExpressionVariable(const ClangExpressionVariable &)=delete
Members.
void EnableJITVars(uint64_t parser_id)
Make this variable usable for materializing for the JIT by allocating space for JIT-specific variable...
void EnableParserVars(uint64_t parser_id)
Make this variable usable by the parser by allocating space for parser- specific variables.
void DisableParserVars(uint64_t parser_id)
Deallocate parser-specific variables.
std::map< uint64_t, ParserVars > ParserVarMap
A uniqued constant string class.
Definition: ConstString.h:40
"lldb/Target/ExecutionContextScope.h" Inherit from this if your object can reconstruct its execution ...
"lldb/Target/ExecutionContext.h" A class that contains an execution context.
"lldb/Expression/ExpressionVariable.h" A list of variable references.
size_t GetSize()
Implementation of methods in ExpressionVariableListBase.
lldb::ExpressionVariableSP GetVariableAtIndex(size_t index)
A class that represents a running process on the host machine.
std::function< lldb::ValueObjectSP(ConstString, StackFrame *)> ValueObjectProviderTy
Functor that returns a ValueObjectSP for a variable given its name and the StackFrame of interest.
std::shared_ptr< lldb_private::ValueObject > ValueObjectSP
Definition: lldb-forward.h:475
std::shared_ptr< lldb_private::ExpressionVariable > ExpressionVariableSP
Definition: lldb-forward.h:346
uint64_t offset_t
Definition: lldb-types.h:85
ByteOrder
Byte ordering definitions.
std::shared_ptr< lldb_private::Variable > VariableSP
Definition: lldb-forward.h:477
Definition: Debugger.h:54
The following values are valid if the variable is used by JIT code.
size_t m_size
The space required for the variable, in bytes.
lldb::offset_t m_alignment
The required alignment of the variable, in bytes.
lldb::offset_t m_offset
The offset of the variable in the struct, in bytes.