1 | //===-- Unwind.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_UNWIND_H |
10 | #define LLDB_TARGET_UNWIND_H |
11 | |
12 | #include <mutex> |
13 | |
14 | #include "lldb/lldb-private.h" |
15 | |
16 | namespace lldb_private { |
17 | |
18 | class Unwind { |
19 | protected: |
20 | // Classes that inherit from Unwind can see and modify these |
21 | Unwind(Thread &thread) : m_thread(thread) {} |
22 | |
23 | public: |
24 | virtual ~Unwind() = default; |
25 | |
26 | void Clear() { |
27 | std::lock_guard<std::recursive_mutex> guard(m_unwind_mutex); |
28 | DoClear(); |
29 | } |
30 | |
31 | uint32_t GetFrameCount() { |
32 | std::lock_guard<std::recursive_mutex> guard(m_unwind_mutex); |
33 | return DoGetFrameCount(); |
34 | } |
35 | |
36 | uint32_t GetFramesUpTo(uint32_t end_idx) { |
37 | lldb::addr_t cfa; |
38 | lldb::addr_t pc; |
39 | uint32_t idx; |
40 | bool behaves_like_zeroth_frame = (end_idx == 0); |
41 | |
42 | for (idx = 0; idx < end_idx; idx++) { |
43 | if (!DoGetFrameInfoAtIndex(frame_idx: idx, cfa, pc, behaves_like_zeroth_frame)) { |
44 | break; |
45 | } |
46 | } |
47 | return idx; |
48 | } |
49 | |
50 | bool GetFrameInfoAtIndex(uint32_t frame_idx, lldb::addr_t &cfa, |
51 | lldb::addr_t &pc, bool &behaves_like_zeroth_frame) { |
52 | std::lock_guard<std::recursive_mutex> guard(m_unwind_mutex); |
53 | return DoGetFrameInfoAtIndex(frame_idx, cfa, pc, behaves_like_zeroth_frame); |
54 | } |
55 | |
56 | lldb::RegisterContextSP CreateRegisterContextForFrame(StackFrame *frame) { |
57 | std::lock_guard<std::recursive_mutex> guard(m_unwind_mutex); |
58 | return DoCreateRegisterContextForFrame(frame); |
59 | } |
60 | |
61 | Thread &GetThread() { return m_thread; } |
62 | |
63 | protected: |
64 | // Classes that inherit from Unwind can see and modify these |
65 | virtual void DoClear() = 0; |
66 | |
67 | virtual uint32_t DoGetFrameCount() = 0; |
68 | |
69 | virtual bool DoGetFrameInfoAtIndex(uint32_t frame_idx, lldb::addr_t &cfa, |
70 | lldb::addr_t &pc, |
71 | bool &behaves_like_zeroth_frame) = 0; |
72 | |
73 | virtual lldb::RegisterContextSP |
74 | DoCreateRegisterContextForFrame(StackFrame *frame) = 0; |
75 | |
76 | Thread &m_thread; |
77 | std::recursive_mutex m_unwind_mutex; |
78 | |
79 | private: |
80 | Unwind(const Unwind &) = delete; |
81 | const Unwind &operator=(const Unwind &) = delete; |
82 | }; |
83 | |
84 | } // namespace lldb_private |
85 | |
86 | #endif // LLDB_TARGET_UNWIND_H |
87 | |