1 //===-- ClangUserExpression.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_ClangUserExpression_h_ 11 #define liblldb_ClangUserExpression_h_ 12 13 // C Includes 14 // C++ Includes 15 #include <vector> 16 17 // Other libraries and framework includes 18 // Project includes 19 #include "ASTStructExtractor.h" 20 #include "ASTResultSynthesizer.h" 21 #include "ClangExpressionDeclMap.h" 22 #include "ClangExpressionHelper.h" 23 #include "ClangExpressionVariable.h" 24 #include "IRForTarget.h" 25 26 #include "lldb/lldb-forward.h" 27 #include "lldb/lldb-private.h" 28 #include "lldb/Core/Address.h" 29 #include "lldb/Core/ClangForward.h" 30 #include "lldb/Expression/LLVMUserExpression.h" 31 #include "lldb/Expression/Materializer.h" 32 #include "lldb/Target/ExecutionContext.h" 33 34 namespace lldb_private 35 { 36 37 //---------------------------------------------------------------------- 38 /// @class ClangUserExpression ClangUserExpression.h "lldb/Expression/ClangUserExpression.h" 39 /// @brief Encapsulates a single expression for use with Clang 40 /// 41 /// LLDB uses expressions for various purposes, notably to call functions 42 /// and as a backend for the expr command. ClangUserExpression encapsulates 43 /// the objects needed to parse and interpret or JIT an expression. It 44 /// uses the Clang parser to produce LLVM IR from the expression. 45 //---------------------------------------------------------------------- 46 class ClangUserExpression : public LLVMUserExpression 47 { 48 public: 49 enum { kDefaultTimeout = 500000u }; 50 51 class ClangUserExpressionHelper : public ClangExpressionHelper 52 { 53 public: 54 ClangUserExpressionHelper (Target &target) : 55 m_target(target) 56 { 57 } 58 59 ~ClangUserExpressionHelper() override = default; 60 61 //------------------------------------------------------------------ 62 /// Return the object that the parser should use when resolving external 63 /// values. May be NULL if everything should be self-contained. 64 //------------------------------------------------------------------ 65 ClangExpressionDeclMap * 66 DeclMap() override 67 { 68 return m_expr_decl_map_up.get(); 69 } 70 71 void 72 ResetDeclMap() 73 { 74 m_expr_decl_map_up.reset(); 75 } 76 77 void 78 ResetDeclMap (ExecutionContext & exe_ctx, Materializer::PersistentVariableDelegate &result_delegate, bool keep_result_in_memory); 79 80 //------------------------------------------------------------------ 81 /// Return the object that the parser should allow to access ASTs. 82 /// May be NULL if the ASTs do not need to be transformed. 83 /// 84 /// @param[in] passthrough 85 /// The ASTConsumer that the returned transformer should send 86 /// the ASTs to after transformation. 87 //------------------------------------------------------------------ 88 clang::ASTConsumer * 89 ASTTransformer(clang::ASTConsumer *passthrough) override; 90 91 private: 92 Target &m_target; 93 std::unique_ptr<ClangExpressionDeclMap> m_expr_decl_map_up; 94 std::unique_ptr<ASTStructExtractor> m_struct_extractor_up; ///< The class that generates the argument struct layout. 95 std::unique_ptr<ASTResultSynthesizer> m_result_synthesizer_up; 96 }; 97 98 //------------------------------------------------------------------ 99 /// Constructor 100 /// 101 /// @param[in] expr 102 /// The expression to parse. 103 /// 104 /// @param[in] expr_prefix 105 /// If non-NULL, a C string containing translation-unit level 106 /// definitions to be included when the expression is parsed. 107 /// 108 /// @param[in] language 109 /// If not eLanguageTypeUnknown, a language to use when parsing 110 /// the expression. Currently restricted to those languages 111 /// supported by Clang. 112 /// 113 /// @param[in] desired_type 114 /// If not eResultTypeAny, the type to use for the expression 115 /// result. 116 //------------------------------------------------------------------ 117 ClangUserExpression (ExecutionContextScope &exe_scope, 118 const char *expr, 119 const char *expr_prefix, 120 lldb::LanguageType language, 121 ResultType desired_type, 122 const EvaluateExpressionOptions &options); 123 124 ~ClangUserExpression() override; 125 126 //------------------------------------------------------------------ 127 /// Parse the expression 128 /// 129 /// @param[in] error_stream 130 /// A stream to print parse errors and warnings to. 131 /// 132 /// @param[in] exe_ctx 133 /// The execution context to use when looking up entities that 134 /// are needed for parsing (locations of functions, types of 135 /// variables, persistent variables, etc.) 136 /// 137 /// @param[in] execution_policy 138 /// Determines whether interpretation is possible or mandatory. 139 /// 140 /// @param[in] keep_result_in_memory 141 /// True if the resulting persistent variable should reside in 142 /// target memory, if applicable. 143 /// 144 /// @return 145 /// True on success (no errors); false otherwise. 146 //------------------------------------------------------------------ 147 bool 148 Parse (Stream &error_stream, 149 ExecutionContext &exe_ctx, 150 lldb_private::ExecutionPolicy execution_policy, 151 bool keep_result_in_memory, 152 bool generate_debug_info) override; 153 154 ExpressionTypeSystemHelper * 155 GetTypeSystemHelper () override 156 { 157 return &m_type_system_helper; 158 } 159 160 ClangExpressionDeclMap * 161 DeclMap () 162 { 163 return m_type_system_helper.DeclMap(); 164 } 165 166 void 167 ResetDeclMap () 168 { 169 m_type_system_helper.ResetDeclMap(); 170 } 171 172 void 173 ResetDeclMap (ExecutionContext & exe_ctx, Materializer::PersistentVariableDelegate &result_delegate, bool keep_result_in_memory) 174 { 175 m_type_system_helper.ResetDeclMap(exe_ctx, result_delegate, keep_result_in_memory); 176 } 177 178 lldb::ExpressionVariableSP 179 GetResultAfterDematerialization(ExecutionContextScope *exe_scope) override; 180 181 private: 182 //------------------------------------------------------------------ 183 /// Populate m_in_cplusplus_method and m_in_objectivec_method based on the environment. 184 //------------------------------------------------------------------ 185 186 void 187 ScanContext (ExecutionContext &exe_ctx, 188 lldb_private::Error &err) override; 189 190 bool 191 AddArguments (ExecutionContext &exe_ctx, 192 std::vector<lldb::addr_t> &args, 193 lldb::addr_t struct_address, 194 Stream &error_stream) override; 195 196 ClangUserExpressionHelper m_type_system_helper; 197 198 class ResultDelegate : public Materializer::PersistentVariableDelegate 199 { 200 public: 201 ResultDelegate(); 202 ConstString GetName() override; 203 void DidDematerialize(lldb::ExpressionVariableSP &variable) override; 204 205 void RegisterPersistentState(PersistentExpressionState *persistent_state); 206 lldb::ExpressionVariableSP &GetVariable(); 207 208 private: 209 PersistentExpressionState *m_persistent_state; 210 lldb::ExpressionVariableSP m_variable; 211 }; 212 213 ResultDelegate m_result_delegate; 214 }; 215 216 } // namespace lldb_private 217 218 #endif // liblldb_ClangUserExpression_h_ 219