1 //===-- Expression.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_EXPRESSION_H 10 #define LLDB_EXPRESSION_EXPRESSION_H 11 12 #include <map> 13 #include <string> 14 #include <vector> 15 16 17 #include "lldb/Expression/ExpressionTypeSystemHelper.h" 18 #include "lldb/lldb-forward.h" 19 #include "lldb/lldb-private.h" 20 21 namespace lldb_private { 22 23 /// \class Expression Expression.h "lldb/Expression/Expression.h" Encapsulates 24 /// a single expression for use in lldb 25 /// 26 /// LLDB uses expressions for various purposes, notably to call functions 27 /// and as a backend for the expr command. Expression encapsulates the 28 /// objects needed to parse and interpret or JIT an expression. It uses the 29 /// expression parser appropriate to the language of the expression to produce 30 /// LLVM IR from the expression. 31 class Expression { 32 public: 33 enum ResultType { eResultTypeAny, eResultTypeId }; 34 35 Expression(Target &target); 36 37 Expression(ExecutionContextScope &exe_scope); 38 39 /// Destructor 40 virtual ~Expression() = default; 41 42 /// Return the string that the parser should parse. Must be a full 43 /// translation unit. 44 virtual const char *Text() = 0; 45 46 /// Return the function name that should be used for executing the 47 /// expression. Text() should contain the definition of this function. 48 virtual const char *FunctionName() = 0; 49 50 /// Return the language that should be used when parsing. To use the 51 /// default, return eLanguageTypeUnknown. 52 virtual lldb::LanguageType Language() const { 53 return lldb::eLanguageTypeUnknown; 54 } 55 56 /// Return the Materializer that the parser should use when registering 57 /// external values. 58 virtual Materializer *GetMaterializer() { return nullptr; } 59 60 /// Return the desired result type of the function, or eResultTypeAny if 61 /// indifferent. 62 virtual ResultType DesiredResultType() { return eResultTypeAny; } 63 64 /// Flags 65 66 /// Return true if validation code should be inserted into the expression. 67 virtual bool NeedsValidation() = 0; 68 69 /// Return true if external variables in the expression should be resolved. 70 virtual bool NeedsVariableResolution() = 0; 71 72 virtual EvaluateExpressionOptions *GetOptions() { return nullptr; }; 73 74 /// Return the address of the function's JIT-compiled code, or 75 /// LLDB_INVALID_ADDRESS if the function is not JIT compiled 76 lldb::addr_t StartAddress() { return m_jit_start_addr; } 77 78 /// Called to notify the expression that it is about to be executed. 79 virtual void WillStartExecuting() {} 80 81 /// Called to notify the expression that its execution has finished. 82 virtual void DidFinishExecuting() {} 83 84 virtual ExpressionTypeSystemHelper *GetTypeSystemHelper() { return nullptr; } 85 86 // LLVM RTTI support 87 virtual bool isA(const void *ClassID) const = 0; 88 89 protected: 90 lldb::TargetWP m_target_wp; /// Expression's always have to have a target... 91 lldb::ProcessWP m_jit_process_wp; /// An expression might have a process, but 92 /// it doesn't need to (e.g. calculator 93 /// mode.) 94 lldb::addr_t m_jit_start_addr; ///< The address of the JITted function within 95 ///the JIT allocation. LLDB_INVALID_ADDRESS if 96 ///invalid. 97 lldb::addr_t m_jit_end_addr; ///< The address of the JITted function within 98 ///the JIT allocation. LLDB_INVALID_ADDRESS if 99 ///invalid. 100 }; 101 102 } // namespace lldb_private 103 104 #endif // LLDB_EXPRESSION_EXPRESSION_H 105