ClangExpressionParser.h revision 321369 
1//===-- ClangExpressionParser.h ---------------------------------*- 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#ifndef liblldb_ClangExpressionParser_h_
11#define liblldb_ClangExpressionParser_h_
12
13#include "lldb/Core/ArchSpec.h"
14#include "lldb/Core/ClangForward.h"
15#include "lldb/Expression/DiagnosticManager.h"
16#include "lldb/Expression/ExpressionParser.h"
17#include "lldb/Utility/Status.h"
18#include "lldb/lldb-public.h"
19
20#include <string>
21#include <vector>
22
23namespace lldb_private {
24
25class IRExecutionUnit;
26
27//----------------------------------------------------------------------
28/// @class ClangExpressionParser ClangExpressionParser.h
29/// "lldb/Expression/ClangExpressionParser.h"
30/// @brief Encapsulates an instance of Clang that can parse expressions.
31///
32/// ClangExpressionParser is responsible for preparing an instance of
33/// ClangExpression for execution.  ClangExpressionParser uses ClangExpression
34/// as a glorified parameter list, performing the required parsing and
35/// conversion to formats (DWARF bytecode, or JIT compiled machine code)
36/// that can be executed.
37//----------------------------------------------------------------------
38class ClangExpressionParser : public ExpressionParser {
39public:
40  //------------------------------------------------------------------
41  /// Constructor
42  ///
43  /// Initializes class variables.
44  ///
45  /// @param[in] exe_scope,
46  ///     If non-NULL, an execution context scope that can help to
47  ///     correctly create an expression with a valid process for
48  ///     optional tuning Objective-C runtime support. Can be NULL.
49  ///
50  /// @param[in] expr
51  ///     The expression to be parsed.
52  //------------------------------------------------------------------
53  ClangExpressionParser(ExecutionContextScope *exe_scope, Expression &expr,
54                        bool generate_debug_info);
55
56  //------------------------------------------------------------------
57  /// Destructor
58  //------------------------------------------------------------------
59  ~ClangExpressionParser() override;
60
61  //------------------------------------------------------------------
62  /// Parse a single expression and convert it to IR using Clang.  Don't
63  /// wrap the expression in anything at all.
64  ///
65  /// @param[in] diagnostic_manager
66  ///     The diagnostic manager to report errors to.
67  ///
68  /// @return
69  ///     The number of errors encountered during parsing.  0 means
70  ///     success.
71  //------------------------------------------------------------------
72  unsigned Parse(DiagnosticManager &diagnostic_manager) override;
73
74  bool RewriteExpression(DiagnosticManager &diagnostic_manager) override;
75
76  //------------------------------------------------------------------
77  /// Ready an already-parsed expression for execution, possibly
78  /// evaluating it statically.
79  ///
80  /// @param[out] func_addr
81  ///     The address to which the function has been written.
82  ///
83  /// @param[out] func_end
84  ///     The end of the function's allocated memory region.  (func_addr
85  ///     and func_end do not delimit an allocated region; the allocated
86  ///     region may begin before func_addr.)
87  ///
88  /// @param[in] execution_unit_sp
89  ///     After parsing, ownership of the execution unit for
90  ///     for the expression is handed to this shared pointer.
91  ///
92  /// @param[in] exe_ctx
93  ///     The execution context to write the function into.
94  ///
95  /// @param[out] evaluated_statically
96  ///     Set to true if the expression could be interpreted statically;
97  ///     untouched otherwise.
98  ///
99  /// @param[out] const_result
100  ///     If the result of the expression is constant, and the
101  ///     expression has no side effects, this is set to the result of the
102  ///     expression.
103  ///
104  /// @param[in] execution_policy
105  ///     Determines whether the expression must be JIT-compiled, must be
106  ///     evaluated statically, or whether this decision may be made
107  ///     opportunistically.
108  ///
109  /// @return
110  ///     An error code indicating the success or failure of the operation.
111  ///     Test with Success().
112  //------------------------------------------------------------------
113  Status
114  PrepareForExecution(lldb::addr_t &func_addr, lldb::addr_t &func_end,
115                      lldb::IRExecutionUnitSP &execution_unit_sp,
116                      ExecutionContext &exe_ctx, bool &can_interpret,
117                      lldb_private::ExecutionPolicy execution_policy) override;
118
119  //------------------------------------------------------------------
120  /// Run all static initializers for an execution unit.
121  ///
122  /// @param[in] execution_unit_sp
123  ///     The execution unit.
124  ///
125  /// @param[in] exe_ctx
126  ///     The execution context to use when running them.  Thread can't be null.
127  ///
128  /// @return
129  ///     The error code indicating the
130  //------------------------------------------------------------------
131  Status RunStaticInitializers(lldb::IRExecutionUnitSP &execution_unit_sp,
132                               ExecutionContext &exe_ctx);
133
134  //------------------------------------------------------------------
135  /// Returns a string representing current ABI.
136  ///
137  /// @param[in] target_arch
138  ///     The target architecture.
139  ///
140  /// @return
141  ///     A string representing target ABI for the current architecture.
142  //-------------------------------------------------------------------
143  std::string GetClangTargetABI(const ArchSpec &target_arch);
144
145private:
146  std::unique_ptr<llvm::LLVMContext>
147      m_llvm_context; ///< The LLVM context to generate IR into
148  std::unique_ptr<clang::FileManager>
149      m_file_manager; ///< The Clang file manager object used by the compiler
150  std::unique_ptr<clang::CompilerInstance>
151      m_compiler; ///< The Clang compiler used to parse expressions into IR
152  std::unique_ptr<clang::Builtin::Context>
153      m_builtin_context; ///< Context for Clang built-ins
154  std::unique_ptr<clang::SelectorTable>
155      m_selector_table; ///< Selector table for Objective-C methods
156  std::unique_ptr<clang::CodeGenerator>
157      m_code_generator; ///< The Clang object that generates IR
158
159  class LLDBPreprocessorCallbacks;
160  LLDBPreprocessorCallbacks *m_pp_callbacks; ///< Called when the preprocessor
161                                             ///encounters module imports
162  std::unique_ptr<ClangASTContext> m_ast_context;
163};
164}
165
166#endif // liblldb_ClangExpressionParser_h_
167