1 //===-- UtilityFunction.h ----------------------------------------*- C++ 2 //-*-===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef liblldb_UtilityFunction_h_ 11 #define liblldb_UtilityFunction_h_ 12 13 #include <memory> 14 #include <string> 15 16 #include "lldb/Expression/Expression.h" 17 #include "lldb/lldb-forward.h" 18 #include "lldb/lldb-private.h" 19 20 namespace lldb_private { 21 22 /// \class UtilityFunction UtilityFunction.h 23 /// "lldb/Expression/UtilityFunction.h" Encapsulates a bit of source code that 24 /// provides a function that is callable 25 /// 26 /// LLDB uses expressions for various purposes, notably to call functions 27 /// and as a backend for the expr command. UtilityFunction encapsulates a 28 /// self-contained function meant to be used from other code. Utility 29 /// functions can perform error-checking for ClangUserExpressions, 30 class UtilityFunction : public Expression { 31 public: 32 /// LLVM-style RTTI support. 33 static bool classof(const Expression *E) { 34 return E->getKind() == eKindUtilityFunction; 35 } 36 37 /// Constructor 38 /// 39 /// \param[in] text 40 /// The text of the function. Must be a full translation unit. 41 /// 42 /// \param[in] name 43 /// The name of the function, as used in the text. 44 UtilityFunction(ExecutionContextScope &exe_scope, const char *text, 45 const char *name, ExpressionKind kind); 46 47 ~UtilityFunction() override; 48 49 /// Install the utility function into a process 50 /// 51 /// \param[in] diagnostic_manager 52 /// A diagnostic manager to print parse errors and warnings to. 53 /// 54 /// \param[in] exe_ctx 55 /// The execution context to install the utility function to. 56 /// 57 /// \return 58 /// True on success (no errors); false otherwise. 59 virtual bool Install(DiagnosticManager &diagnostic_manager, 60 ExecutionContext &exe_ctx) = 0; 61 62 /// Check whether the given PC is inside the function 63 /// 64 /// Especially useful if the function dereferences nullptr to indicate a 65 /// failed assert. 66 /// 67 /// \param[in] pc 68 /// The program counter to check. 69 /// 70 /// \return 71 /// True if the program counter falls within the function's bounds; 72 /// false if not (or the function is not JIT compiled) 73 bool ContainsAddress(lldb::addr_t address) { 74 // nothing is both >= LLDB_INVALID_ADDRESS and < LLDB_INVALID_ADDRESS, so 75 // this always returns false if the function is not JIT compiled yet 76 return (address >= m_jit_start_addr && address < m_jit_end_addr); 77 } 78 79 /// Return the string that the parser should parse. Must be a full 80 /// translation unit. 81 const char *Text() override { return m_function_text.c_str(); } 82 83 /// Return the function name that should be used for executing the 84 /// expression. Text() should contain the definition of this function. 85 const char *FunctionName() override { return m_function_name.c_str(); } 86 87 /// Return the object that the parser should use when registering local 88 /// variables. May be nullptr if the Expression doesn't care. 89 ExpressionVariableList *LocalVariables() { return nullptr; } 90 91 /// Return true if validation code should be inserted into the expression. 92 bool NeedsValidation() override { return false; } 93 94 /// Return true if external variables in the expression should be resolved. 95 bool NeedsVariableResolution() override { return false; } 96 97 // This makes the function caller function. Pass in the ThreadSP if you have 98 // one available, compilation can end up calling code (e.g. to look up 99 // indirect functions) and we don't want this to wander onto another thread. 100 FunctionCaller *MakeFunctionCaller(const CompilerType &return_type, 101 const ValueList &arg_value_list, 102 lldb::ThreadSP compilation_thread, 103 Status &error); 104 105 // This one retrieves the function caller that is already made. If you 106 // haven't made it yet, this returns nullptr 107 FunctionCaller *GetFunctionCaller() { return m_caller_up.get(); } 108 109 protected: 110 std::shared_ptr<IRExecutionUnit> m_execution_unit_sp; 111 lldb::ModuleWP m_jit_module_wp; 112 std::string m_function_text; ///< The text of the function. Must be a 113 ///well-formed translation unit. 114 std::string m_function_name; ///< The name of the function. 115 std::unique_ptr<FunctionCaller> m_caller_up; 116 }; 117 118 } // namespace lldb_private 119 120 #endif // liblldb_UtilityFunction_h_ 121