1 //===-- SymbolContextScope.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_SymbolContextScope_h_ 11 #define liblldb_SymbolContextScope_h_ 12 13 // C Includes 14 // C++ Includes 15 // Other libraries and framework includes 16 // Project includes 17 #include "lldb/lldb-private.h" 18 19 namespace lldb_private { 20 21 //---------------------------------------------------------------------- 22 /// @class SymbolContextScope SymbolContextScope.h "lldb/Symbol/SymbolContextScope.h" 23 /// @brief Inherit from this if your object is part of a symbol context 24 /// and can reconstruct its symbol context. 25 /// 26 /// Many objects that are part of a symbol context that have pointers 27 /// back to parent objects that own them. Any members of a symbol 28 /// context that, once they are built, will not go away, can inherit 29 /// from this pure virtual class and can then reconstruct their symbol 30 /// context without having to keep a complete SymbolContext object in 31 /// the object. 32 /// 33 /// Examples of these objects include: 34 /// @li Module 35 /// @li CompileUnit 36 /// @li Function 37 /// @li Block 38 /// @li Symbol 39 /// 40 /// Other objects can store a "SymbolContextScope *" using any pointers 41 /// to one of the above objects. This allows clients to hold onto a 42 /// pointer that uniquely will identify a symbol context. Those clients 43 /// can then always reconstruct the symbol context using the pointer, or 44 /// use it to uniquely identify a symbol context for an object. 45 /// 46 /// Example objects include that currently use "SymbolContextScope *" 47 /// objects include: 48 /// @li Variable objects that can reconstruct where they are scoped 49 /// by making sure the SymbolContextScope * comes from the scope 50 /// in which the variable was declared. If a variable is a global, 51 /// the appropriate CompileUnit * will be used when creating the 52 /// variable. A static function variables, can the Block scope 53 /// in which the variable is defined. Function arguments can use 54 /// the Function object as their scope. The SymbolFile parsers 55 /// will set these correctly as the variables are parsed. 56 /// @li Type objects that know exactly in which scope they 57 /// originated much like the variables above. 58 /// @li StackID objects that are able to know that if the CFA 59 /// (stack pointer at the beginning of a function) and the 60 /// start PC for the function/symbol and the SymbolContextScope 61 /// pointer (a unique pointer that identifies a symbol context 62 /// location) match within the same thread, that the stack 63 /// frame is the same as the previous stack frame. 64 /// 65 /// Objects that adhere to this protocol can reconstruct enough of a 66 /// symbol context to allow functions that take a symbol context to be 67 /// called. Lists can also be created using a SymbolContextScope* and 68 /// and object pairs that allow large collections of objects to be 69 /// passed around with minimal overhead. 70 //---------------------------------------------------------------------- 71 class SymbolContextScope 72 { 73 public: 74 virtual ~SymbolContextScope()75 ~SymbolContextScope () {} 76 77 //------------------------------------------------------------------ 78 /// Reconstruct the object's symbolc context into \a sc. 79 /// 80 /// The object should fill in as much of the SymbolContext as it 81 /// can so function calls that require a symbol context can be made 82 /// for the given object. 83 /// 84 /// @param[out] sc 85 /// A symbol context object pointer that gets filled in. 86 //------------------------------------------------------------------ 87 virtual void 88 CalculateSymbolContext (SymbolContext *sc) = 0; 89 90 91 virtual lldb::ModuleSP CalculateSymbolContextModule()92 CalculateSymbolContextModule () 93 { 94 return lldb::ModuleSP(); 95 } 96 97 virtual CompileUnit * CalculateSymbolContextCompileUnit()98 CalculateSymbolContextCompileUnit () 99 { 100 return NULL; 101 } 102 103 virtual Function * CalculateSymbolContextFunction()104 CalculateSymbolContextFunction () 105 { 106 return NULL; 107 } 108 109 virtual Block * CalculateSymbolContextBlock()110 CalculateSymbolContextBlock () 111 { 112 return NULL; 113 } 114 115 virtual Symbol * CalculateSymbolContextSymbol()116 CalculateSymbolContextSymbol () 117 { 118 return NULL; 119 } 120 121 //------------------------------------------------------------------ 122 /// Dump the object's symbolc context to the stream \a s. 123 /// 124 /// The object should dump its symbol context to the stream \a s. 125 /// This function is widely used in the DumpDebug and verbose output 126 /// for lldb objets. 127 /// 128 /// @param[in] s 129 /// The stream to which to dump the object's symbol context. 130 //------------------------------------------------------------------ 131 virtual void 132 DumpSymbolContext (Stream *s) = 0; 133 }; 134 135 } // namespace lldb_private 136 137 #endif // liblldb_SymbolContextScope_h_ 138