1 //===-- UnwindLLDB.h --------------------------------------------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 #ifndef lldb_UnwindLLDB_h_
10 #define lldb_UnwindLLDB_h_
14 #include "lldb/Symbol/FuncUnwinders.h"
15 #include "lldb/Symbol/SymbolContext.h"
16 #include "lldb/Symbol/UnwindPlan.h"
17 #include "lldb/Target/RegisterContext.h"
18 #include "lldb/Target/Unwind.h"
19 #include "lldb/Utility/ConstString.h"
20 #include "lldb/lldb-public.h"
22 namespace lldb_private {
24 class RegisterContextLLDB;
26 class UnwindLLDB : public lldb_private::Unwind {
28 UnwindLLDB(lldb_private::Thread &thread);
30 ~UnwindLLDB() override = default;
32 enum RegisterSearchResult {
39 friend class lldb_private::RegisterContextLLDB;
41 struct RegisterLocation {
42 enum RegisterLocationTypes {
43 eRegisterNotSaved = 0, // register was not preserved by callee. If
44 // volatile reg, is unavailable
45 eRegisterSavedAtMemoryLocation, // register is saved at a specific word of
46 // target mem (target_memory_location)
47 eRegisterInRegister, // register is available in a (possible other)
48 // register (register_number)
49 eRegisterSavedAtHostMemoryLocation, // register is saved at a word in
50 // lldb's address space
51 eRegisterValueInferred, // register val was computed (and is in
53 eRegisterInLiveRegisterContext // register value is in a live (stack frame
58 lldb::addr_t target_memory_location;
60 register_number; // in eRegisterKindLLDB register numbering system
61 void *host_memory_location;
62 uint64_t inferred_value; // eRegisterValueInferred - e.g. stack pointer ==
67 void DoClear() override {
69 m_candidate_frame.reset();
70 m_unwind_complete = false;
73 uint32_t DoGetFrameCount() override;
75 bool DoGetFrameInfoAtIndex(uint32_t frame_idx, lldb::addr_t &cfa,
76 lldb::addr_t &start_pc) override;
78 lldb::RegisterContextSP
79 DoCreateRegisterContextForFrame(lldb_private::StackFrame *frame) override;
81 typedef std::shared_ptr<RegisterContextLLDB> RegisterContextLLDBSP;
83 // Needed to retrieve the "next" frame (e.g. frame 2 needs to retrieve frame
84 // 1's RegisterContextLLDB)
85 // The RegisterContext for frame_num must already exist or this returns an
86 // empty shared pointer.
87 RegisterContextLLDBSP GetRegisterContextForFrameNum(uint32_t frame_num);
89 // Iterate over the RegisterContextLLDB's in our m_frames vector, look for the
91 // has a saved location for this reg.
92 bool SearchForSavedLocationForRegister(
93 uint32_t lldb_regnum, lldb_private::UnwindLLDB::RegisterLocation ®loc,
94 uint32_t starting_frame_num, bool pc_register);
96 /// Provide the list of user-specified trap handler functions
98 /// The Platform is one source of trap handler function names; that
99 /// may be augmented via a setting. The setting needs to be converted
100 /// into an array of ConstStrings before it can be used - we only want
101 /// to do that once per thread so it's here in the UnwindLLDB object.
104 /// Vector of ConstStrings of trap handler function names. May be
106 const std::vector<ConstString> &GetUserSpecifiedTrapHandlerFunctionNames() {
107 return m_user_supplied_trap_handler_functions;
112 lldb::addr_t start_pc; // The start address of the function/symbol for this
113 // frame - current pc if unknown
114 lldb::addr_t cfa; // The canonical frame address for this stack frame
115 lldb_private::SymbolContext sctx; // A symbol context we'll contribute to &
116 // provide to the StackFrame creation
117 RegisterContextLLDBSP
118 reg_ctx_lldb_sp; // These are all RegisterContextLLDB's
121 : start_pc(LLDB_INVALID_ADDRESS), cfa(LLDB_INVALID_ADDRESS), sctx(),
125 DISALLOW_COPY_AND_ASSIGN(Cursor);
128 typedef std::shared_ptr<Cursor> CursorSP;
129 std::vector<CursorSP> m_frames;
130 CursorSP m_candidate_frame;
131 bool m_unwind_complete; // If this is true, we've enumerated all the frames in
132 // the stack, and m_frames.size() is the
133 // number of frames, etc. Otherwise we've only gone as far as directly asked,
134 // and m_frames.size()
135 // is how far we've currently gone.
137 std::vector<ConstString> m_user_supplied_trap_handler_functions;
139 // Check if Full UnwindPlan of First frame is valid or not.
140 // If not then try Fallback UnwindPlan of the frame. If Fallback
141 // UnwindPlan succeeds then update the Full UnwindPlan with the
142 // Fallback UnwindPlan.
143 void UpdateUnwindPlanForFirstFrameIfInvalid(ABI *abi);
145 CursorSP GetOneMoreFrame(ABI *abi);
147 bool AddOneMoreFrame(ABI *abi);
149 bool AddFirstFrame();
151 // For UnwindLLDB only
152 DISALLOW_COPY_AND_ASSIGN(UnwindLLDB);
155 } // namespace lldb_private
157 #endif // lldb_UnwindLLDB_h_