lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.h

   1 //===-- ClangExpressionParser.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_CLANGEXPRESSIONPARSER_H
  10 #define LLDB_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_CLANGEXPRESSIONPARSER_H
  11
  12 #include "lldb/Expression/DiagnosticManager.h"
  13 #include "lldb/Expression/ExpressionParser.h"
  14 #include "lldb/Utility/ArchSpec.h"
  15 #include "lldb/Utility/Status.h"
  16 #include "lldb/lldb-public.h"
  17
  18 #include <string>
  19 #include <vector>
  20
  21 namespace llvm {
  22 class LLVMContext;
  23 }
  24
  25 namespace clang {
  26 class CodeGenerator;
  27 class CodeCompleteConsumer;
  28 class CompilerInstance;
  29 } // namespace clang
  30
  31 namespace lldb_private {
  32
  33 class IRExecutionUnit;
  34 class TypeSystemClang;
  35
  36 /// \class ClangExpressionParser ClangExpressionParser.h
  37 /// "lldb/Expression/ClangExpressionParser.h" Encapsulates an instance of
  38 /// Clang that can parse expressions.
  39 ///
  40 /// ClangExpressionParser is responsible for preparing an instance of
  41 /// ClangExpression for execution.  ClangExpressionParser uses ClangExpression
  42 /// as a glorified parameter list, performing the required parsing and
  43 /// conversion to formats (DWARF bytecode, or JIT compiled machine code) that
  44 /// can be executed.
  45 class ClangExpressionParser : public ExpressionParser {
  46 public:
  47   /// Constructor
  48   ///
  49   /// Initializes class variables.
  50   ///
  51   /// \param[in] exe_scope
  52   ///     If non-NULL, an execution context scope that can help to
  53   ///     correctly create an expression with a valid process for
  54   ///     optional tuning Objective-C runtime support. Can be NULL.
  55   ///
  56   /// \param[in] expr
  57   ///     The expression to be parsed.
  58   ///
  59   /// @param[in] include_directories
  60   ///     List of include directories that should be used when parsing the
  61   ///     expression.
  62   ///
  63   /// @param[in] filename
  64   ///     Name of the source file that should be used when rendering
  65   ///     diagnostics (i.e. errors, warnings or notes from Clang).
  66   ClangExpressionParser(ExecutionContextScope *exe_scope, Expression &expr,
  67                         bool generate_debug_info,
  68                         std::vector<std::string> include_directories = {},
  69                         std::string filename = "<clang expression>");
  70
  71   /// Destructor
  72   ~ClangExpressionParser() override;
  73
  74   bool Complete(CompletionRequest &request, unsigned line, unsigned pos,
  75                 unsigned typed_pos) override;
  76
  77   /// Parse a single expression and convert it to IR using Clang.  Don't wrap
  78   /// the expression in anything at all.
  79   ///
  80   /// \param[in] diagnostic_manager
  81   ///     The diagnostic manager to report errors to.
  82   ///
  83   /// \return
  84   ///     The number of errors encountered during parsing.  0 means
  85   ///     success.
  86   unsigned Parse(DiagnosticManager &diagnostic_manager);
  87
  88   bool RewriteExpression(DiagnosticManager &diagnostic_manager) override;
  89
  90   /// Ready an already-parsed expression for execution, possibly evaluating it
  91   /// statically.
  92   ///
  93   /// \param[out] func_addr
  94   ///     The address to which the function has been written.
  95   ///
  96   /// \param[out] func_end
  97   ///     The end of the function's allocated memory region.  (func_addr
  98   ///     and func_end do not delimit an allocated region; the allocated
  99   ///     region may begin before func_addr.)
 100   ///
 101   /// \param[in] execution_unit_sp
 102   ///     After parsing, ownership of the execution unit for
 103   ///     for the expression is handed to this shared pointer.
 104   ///
 105   /// \param[in] exe_ctx
 106   ///     The execution context to write the function into.
 107   ///
 108   /// \param[in] execution_policy
 109   ///     Determines whether the expression must be JIT-compiled, must be
 110   ///     evaluated statically, or whether this decision may be made
 111   ///     opportunistically.
 112   ///
 113   /// \return
 114   ///     An error code indicating the success or failure of the operation.
 115   ///     Test with Success().
 116   Status DoPrepareForExecution(
 117       lldb::addr_t &func_addr, lldb::addr_t &func_end,
 118       lldb::IRExecutionUnitSP &execution_unit_sp, ExecutionContext &exe_ctx,
 119       bool &can_interpret,
 120       lldb_private::ExecutionPolicy execution_policy) override;
 121
 122 private:
 123   /// Parses the expression.
 124   ///
 125   /// \param[in] diagnostic_manager
 126   ///     The diagnostic manager that should receive the diagnostics
 127   ///     from the parsing process.
 128   ///
 129   /// \param[in] completion
 130   ///     The completion consumer that should be used during parsing
 131   ///     (or a nullptr if no consumer should be attached).
 132   ///
 133   /// \param[in] completion_line
 134   ///     The line in which the completion marker should be placed.
 135   ///     The first line is represented by the value 0.
 136   ///
 137   /// \param[in] completion_column
 138   ///     The column in which the completion marker should be placed.
 139   ///     The first column is represented by the value 0.
 140   ///
 141   /// \return
 142   ///    The number of parsing errors.
 143   unsigned ParseInternal(DiagnosticManager &diagnostic_manager,
 144                          clang::CodeCompleteConsumer *completion = nullptr,
 145                          unsigned completion_line = 0,
 146                          unsigned completion_column = 0);
 147
 148   std::unique_ptr<llvm::LLVMContext>
 149       m_llvm_context; ///< The LLVM context to generate IR into
 150   std::unique_ptr<clang::CompilerInstance>
 151       m_compiler; ///< The Clang compiler used to parse expressions into IR
 152   std::unique_ptr<clang::CodeGenerator>
 153       m_code_generator; ///< The Clang object that generates IR
 154
 155   class LLDBPreprocessorCallbacks;
 156   LLDBPreprocessorCallbacks *m_pp_callbacks; ///< Called when the preprocessor
 157                                              ///encounters module imports
 158   std::shared_ptr<TypeSystemClang> m_ast_context;
 159
 160   std::vector<std::string> m_include_directories;
 161   /// File name used for the user expression.
 162   std::string m_filename;
 163 };
 164 }
 165
 166 #endif // LLDB_SOURCE_PLUGINS_EXPRESSIONPARSER_CLANG_CLANGEXPRESSIONPARSER_H