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UnwindLLDB.h
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1//===-- UnwindLLDB.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_TARGET_UNWINDLLDB_H
10#define LLDB_TARGET_UNWINDLLDB_H
11
12#include <vector>
13
18#include "lldb/Target/Unwind.h"
20#include "lldb/lldb-public.h"
21
22namespace lldb_private {
23
24class RegisterContextUnwind;
25
27public:
29
30 ~UnwindLLDB() override = default;
31
36 };
37
38protected:
40
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
52 // inferred_value)
53 eRegisterInLiveRegisterContext // register value is in a live (stack frame
54 // #0) register
55 };
56 int type;
57 union {
59 uint32_t
60 register_number; // in eRegisterKindLLDB register numbering system
62 uint64_t inferred_value; // eRegisterValueInferred - e.g. stack pointer ==
63 // cfa + offset
65 };
66
67 void DoClear() override {
68 m_frames.clear();
69 m_candidate_frame.reset();
70 m_unwind_complete = false;
71 }
72
73 uint32_t DoGetFrameCount() override;
74
75 bool DoGetFrameInfoAtIndex(uint32_t frame_idx, lldb::addr_t &cfa,
76 lldb::addr_t &start_pc,
77 bool &behaves_like_zeroth_frame) override;
78
81
82 typedef std::shared_ptr<RegisterContextUnwind> RegisterContextLLDBSP;
83
84 // Needed to retrieve the "next" frame (e.g. frame 2 needs to retrieve frame
85 // 1's RegisterContextUnwind)
86 // The RegisterContext for frame_num must already exist or this returns an
87 // empty shared pointer.
89
90 // Iterate over the RegisterContextUnwind's in our m_frames vector, look for
91 // the first one that has a saved location for this reg.
93 uint32_t lldb_regnum, lldb_private::UnwindLLDB::RegisterLocation &regloc,
94 uint32_t starting_frame_num, bool pc_register);
95
96 /// Provide the list of user-specified trap handler functions
97 ///
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.
102 ///
103 /// \return
104 /// Vector of ConstStrings of trap handler function names. May be
105 /// empty.
106 const std::vector<ConstString> &GetUserSpecifiedTrapHandlerFunctionNames() {
108 }
109
110private:
111 struct Cursor {
113 LLDB_INVALID_ADDRESS; // The start address of the function/symbol for
114 // this frame - current pc if unknown
115 lldb::addr_t cfa = LLDB_INVALID_ADDRESS; // The canonical frame address for
116 // this stack frame
117 lldb_private::SymbolContext sctx; // A symbol context we'll contribute to &
118 // provide to the StackFrame creation
120 reg_ctx_lldb_sp; // These are all RegisterContextUnwind's
121
122 Cursor() = default;
123
124 private:
125 Cursor(const Cursor &) = delete;
126 const Cursor &operator=(const Cursor &) = delete;
127 };
128
129 typedef std::shared_ptr<Cursor> CursorSP;
130 std::vector<CursorSP> m_frames;
132 bool m_unwind_complete; // If this is true, we've enumerated all the frames in
133 // the stack, and m_frames.size() is the
134 // number of frames, etc. Otherwise we've only gone as far as directly asked,
135 // and m_frames.size()
136 // is how far we've currently gone.
137
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.
145
147
148 bool AddOneMoreFrame(ABI *abi);
149
150 bool AddFirstFrame();
151
152 // For UnwindLLDB only
153 UnwindLLDB(const UnwindLLDB &) = delete;
154 const UnwindLLDB &operator=(const UnwindLLDB &) = delete;
155};
156
157} // namespace lldb_private
158
159#endif // LLDB_TARGET_UNWINDLLDB_H
This base class provides an interface to stack frames.
Definition: StackFrame.h:41
Defines a symbol context baton that can be handed other debug core functions.
Definition: SymbolContext.h:33
void UpdateUnwindPlanForFirstFrameIfInvalid(ABI *abi)
Definition: UnwindLLDB.cpp:296
std::vector< ConstString > m_user_supplied_trap_handler_functions
Definition: UnwindLLDB.h:138
std::vector< CursorSP > m_frames
Definition: UnwindLLDB.h:130
const std::vector< ConstString > & GetUserSpecifiedTrapHandlerFunctionNames()
Provide the list of user-specified trap handler functions.
Definition: UnwindLLDB.h:106
RegisterContextLLDBSP GetRegisterContextForFrameNum(uint32_t frame_num)
Definition: UnwindLLDB.cpp:464
lldb::RegisterContextSP DoCreateRegisterContextForFrame(lldb_private::StackFrame *frame) override
Definition: UnwindLLDB.cpp:434
std::shared_ptr< Cursor > CursorSP
Definition: UnwindLLDB.h:129
bool AddOneMoreFrame(ABI *abi)
Definition: UnwindLLDB.cpp:318
CursorSP GetOneMoreFrame(ABI *abi)
Definition: UnwindLLDB.cpp:114
UnwindLLDB(const UnwindLLDB &)=delete
std::shared_ptr< RegisterContextUnwind > RegisterContextLLDBSP
Definition: UnwindLLDB.h:82
const UnwindLLDB & operator=(const UnwindLLDB &)=delete
bool DoGetFrameInfoAtIndex(uint32_t frame_idx, lldb::addr_t &cfa, lldb::addr_t &start_pc, bool &behaves_like_zeroth_frame) override
Definition: UnwindLLDB.cpp:392
bool SearchForSavedLocationForRegister(uint32_t lldb_regnum, lldb_private::UnwindLLDB::RegisterLocation &regloc, uint32_t starting_frame_num, bool pc_register)
Definition: UnwindLLDB.cpp:471
void DoClear() override
Definition: UnwindLLDB.h:67
~UnwindLLDB() override=default
uint32_t DoGetFrameCount() override
Definition: UnwindLLDB.cpp:41
#define LLDB_INVALID_ADDRESS
Definition: lldb-defines.h:76
A class that represents a running process on the host machine.
Definition: SBAttachInfo.h:14
uint64_t addr_t
Definition: lldb-types.h:79
std::shared_ptr< lldb_private::RegisterContext > RegisterContextSP
Definition: lldb-forward.h:373
RegisterContextLLDBSP reg_ctx_lldb_sp
Definition: UnwindLLDB.h:120
Cursor(const Cursor &)=delete
const Cursor & operator=(const Cursor &)=delete
lldb_private::SymbolContext sctx
Definition: UnwindLLDB.h:117
union lldb_private::UnwindLLDB::RegisterLocation::@38 location