1//===-- UnwindLLDB.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 lldb_UnwindLLDB_h_ 11#define lldb_UnwindLLDB_h_ 12 13// C Includes 14// C++ Includes 15#include <vector> 16 17// Other libraries and framework includes 18// Project includes 19#include "lldb/lldb-public.h" 20#include "lldb/Core/ConstString.h" 21#include "lldb/Symbol/FuncUnwinders.h" 22#include "lldb/Symbol/UnwindPlan.h" 23#include "lldb/Target/RegisterContext.h" 24#include "lldb/Target/Unwind.h" 25 26namespace lldb_private { 27 28class RegisterContextLLDB; 29 30class UnwindLLDB : public lldb_private::Unwind 31{ 32public: 33 UnwindLLDB (lldb_private::Thread &thread); 34 35 ~UnwindLLDB() override = default; 36 37 enum RegisterSearchResult 38 { 39 eRegisterFound = 0, 40 eRegisterNotFound, 41 eRegisterIsVolatile 42 }; 43 44protected: 45 friend class lldb_private::RegisterContextLLDB; 46 47 struct RegisterLocation { 48 enum RegisterLocationTypes 49 { 50 eRegisterNotSaved = 0, // register was not preserved by callee. If volatile reg, is unavailable 51 eRegisterSavedAtMemoryLocation, // register is saved at a specific word of target mem (target_memory_location) 52 eRegisterInRegister, // register is available in a (possible other) register (register_number) 53 eRegisterSavedAtHostMemoryLocation, // register is saved at a word in lldb's address space 54 eRegisterValueInferred, // register val was computed (and is in inferred_value) 55 eRegisterInLiveRegisterContext // register value is in a live (stack frame #0) register 56 }; 57 int type; 58 union 59 { 60 lldb::addr_t target_memory_location; 61 uint32_t register_number; // in eRegisterKindLLDB register numbering system 62 void* host_memory_location; 63 uint64_t inferred_value; // eRegisterValueInferred - e.g. stack pointer == cfa + offset 64 } location; 65 }; 66 67 void 68 DoClear() override 69 { 70 m_frames.clear(); 71 m_candidate_frame.reset(); 72 m_unwind_complete = false; 73 } 74 75 uint32_t 76 DoGetFrameCount() override; 77 78 bool 79 DoGetFrameInfoAtIndex(uint32_t frame_idx, 80 lldb::addr_t& cfa, 81 lldb::addr_t& start_pc) override; 82 83 lldb::RegisterContextSP 84 DoCreateRegisterContextForFrame(lldb_private::StackFrame *frame) override; 85 86 typedef std::shared_ptr<RegisterContextLLDB> RegisterContextLLDBSP; 87 88 // Needed to retrieve the "next" frame (e.g. frame 2 needs to retrieve frame 1's RegisterContextLLDB) 89 // The RegisterContext for frame_num must already exist or this returns an empty shared pointer. 90 RegisterContextLLDBSP 91 GetRegisterContextForFrameNum (uint32_t frame_num); 92 93 // Iterate over the RegisterContextLLDB's in our m_frames vector, look for the first one that 94 // has a saved location for this reg. 95 bool 96 SearchForSavedLocationForRegister (uint32_t lldb_regnum, lldb_private::UnwindLLDB::RegisterLocation ®loc, uint32_t starting_frame_num, bool pc_register); 97 98 99 //------------------------------------------------------------------ 100 /// Provide the list of user-specified trap handler functions 101 /// 102 /// The Platform is one source of trap handler function names; that 103 /// may be augmented via a setting. The setting needs to be converted 104 /// into an array of ConstStrings before it can be used - we only want 105 /// to do that once per thread so it's here in the UnwindLLDB object. 106 /// 107 /// @return 108 /// Vector of ConstStrings of trap handler function names. May be 109 /// empty. 110 //------------------------------------------------------------------ 111 const std::vector<ConstString> & 112 GetUserSpecifiedTrapHandlerFunctionNames () 113 { 114 return m_user_supplied_trap_handler_functions; 115 } 116 117private: 118 struct Cursor 119 { 120 lldb::addr_t start_pc; // The start address of the function/symbol for this frame - current pc if unknown 121 lldb::addr_t cfa; // The canonical frame address for this stack frame 122 lldb_private::SymbolContext sctx; // A symbol context we'll contribute to & provide to the StackFrame creation 123 RegisterContextLLDBSP reg_ctx_lldb_sp; // These are all RegisterContextLLDB's 124 125 Cursor () : start_pc (LLDB_INVALID_ADDRESS), cfa (LLDB_INVALID_ADDRESS), sctx(), reg_ctx_lldb_sp() { } 126 private: 127 DISALLOW_COPY_AND_ASSIGN (Cursor); 128 }; 129 130 typedef std::shared_ptr<Cursor> CursorSP; 131 std::vector<CursorSP> m_frames; 132 CursorSP m_candidate_frame; 133 bool m_unwind_complete; // If this is true, we've enumerated all the frames in the stack, and m_frames.size() is the 134 // number of frames, etc. Otherwise we've only gone as far as directly asked, and m_frames.size() 135 // is how far we've currently gone. 136 137 std::vector<ConstString> m_user_supplied_trap_handler_functions; 138 139 //----------------------------------------------------------------- 140 // Check if Full UnwindPlan of First frame is valid or not. 141 // If not then try Fallback UnwindPlan of the frame. If Fallback 142 // UnwindPlan succeeds then update the Full UnwindPlan with the 143 // Fallback UnwindPlan. 144 //----------------------------------------------------------------- 145 void 146 UpdateUnwindPlanForFirstFrameIfInvalid (ABI* abi); 147 148 CursorSP 149 GetOneMoreFrame (ABI* abi); 150 151 bool 152 AddOneMoreFrame (ABI *abi); 153 154 bool 155 AddFirstFrame (); 156 157 //------------------------------------------------------------------ 158 // For UnwindLLDB only 159 //------------------------------------------------------------------ 160 DISALLOW_COPY_AND_ASSIGN (UnwindLLDB); 161}; 162 163} // namespace lldb_private 164 165#endif // lldb_UnwindLLDB_h_ 166