1 //===-- UnwindTable.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_SYMBOL_UNWINDTABLE_H
10 #define LLDB_SYMBOL_UNWINDTABLE_H
11 
12 #include <map>
13 #include <mutex>
14 #include <optional>
15 
16 #include "lldb/lldb-private.h"
17 
18 namespace lldb_private {
19 
20 // A class which holds all the FuncUnwinders objects for a given ObjectFile.
21 // The UnwindTable is populated with FuncUnwinders objects lazily during the
22 // debug session.
23 
24 class UnwindTable {
25 public:
26   /// Create an Unwind table using the data in the given module.
27   explicit UnwindTable(Module &module);
28 
29   ~UnwindTable();
30 
31   lldb_private::CallFrameInfo *GetObjectFileUnwindInfo();
32 
33   lldb_private::DWARFCallFrameInfo *GetEHFrameInfo();
34   lldb_private::DWARFCallFrameInfo *GetDebugFrameInfo();
35 
36   lldb_private::CompactUnwindInfo *GetCompactUnwindInfo();
37 
38   ArmUnwindInfo *GetArmUnwindInfo();
39   SymbolFile *GetSymbolFile();
40 
41   lldb::FuncUnwindersSP GetFuncUnwindersContainingAddress(const Address &addr,
42                                                           SymbolContext &sc);
43 
44   bool GetAllowAssemblyEmulationUnwindPlans();
45 
46   // Normally when we create a new FuncUnwinders object we track it in this
47   // UnwindTable so it can be reused later.  But for the target modules show-
48   // unwind we want to create brand new UnwindPlans for the function of
49   // interest - so ignore any existing FuncUnwinders for that function and
50   // don't add this new one to our UnwindTable. This FuncUnwinders object does
51   // have a reference to the UnwindTable but the lifetime of this uncached
52   // FuncUnwinders is expected to be short so in practice this will not be a
53   // problem.
54   lldb::FuncUnwindersSP
55   GetUncachedFuncUnwindersContainingAddress(const Address &addr,
56                                             SymbolContext &sc);
57 
58   ArchSpec GetArchitecture();
59 
60 private:
61   void Dump(Stream &s);
62 
63   void Initialize();
64   std::optional<AddressRange> GetAddressRange(const Address &addr,
65                                               SymbolContext &sc);
66 
67   typedef std::map<lldb::addr_t, lldb::FuncUnwindersSP> collection;
68   typedef collection::iterator iterator;
69   typedef collection::const_iterator const_iterator;
70 
71   Module &m_module;
72   collection m_unwinds;
73 
74   bool m_initialized; // delay some initialization until ObjectFile is set up
75   std::mutex m_mutex;
76 
77   std::unique_ptr<CallFrameInfo> m_object_file_unwind_up;
78   std::unique_ptr<DWARFCallFrameInfo> m_eh_frame_up;
79   std::unique_ptr<DWARFCallFrameInfo> m_debug_frame_up;
80   std::unique_ptr<CompactUnwindInfo> m_compact_unwind_up;
81   std::unique_ptr<ArmUnwindInfo> m_arm_unwind_up;
82 
83   UnwindTable(const UnwindTable &) = delete;
84   const UnwindTable &operator=(const UnwindTable &) = delete;
85 };
86 
87 } // namespace lldb_private
88 
89 #endif // LLDB_SYMBOL_UNWINDTABLE_H
90