1//===-- StackID.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_STACKID_H
10#define LLDB_TARGET_STACKID_H
11
12#include "lldb/Core/AddressRange.h"
13#include "lldb/lldb-private.h"
14
15namespace lldb_private {
16
17class StackID {
18public:
19  // Constructors and Destructors
20  StackID()
21      : m_pc(LLDB_INVALID_ADDRESS), m_cfa(LLDB_INVALID_ADDRESS),
22        m_symbol_scope(nullptr) {}
23
24  explicit StackID(lldb::addr_t pc, lldb::addr_t cfa,
25                   SymbolContextScope *symbol_scope)
26      : m_pc(pc), m_cfa(cfa), m_symbol_scope(symbol_scope) {}
27
28  StackID(const StackID &rhs)
29      : m_pc(rhs.m_pc), m_cfa(rhs.m_cfa), m_symbol_scope(rhs.m_symbol_scope) {}
30
31  ~StackID() = default;
32
33  lldb::addr_t GetPC() const { return m_pc; }
34
35  lldb::addr_t GetCallFrameAddress() const { return m_cfa; }
36
37  SymbolContextScope *GetSymbolContextScope() const { return m_symbol_scope; }
38
39  void SetSymbolContextScope(SymbolContextScope *symbol_scope) {
40    m_symbol_scope = symbol_scope;
41  }
42
43  void Clear() {
44    m_pc = LLDB_INVALID_ADDRESS;
45    m_cfa = LLDB_INVALID_ADDRESS;
46    m_symbol_scope = nullptr;
47  }
48
49  bool IsValid() const {
50    return m_pc != LLDB_INVALID_ADDRESS || m_cfa != LLDB_INVALID_ADDRESS;
51  }
52
53  void Dump(Stream *s);
54
55  // Operators
56  const StackID &operator=(const StackID &rhs) {
57    if (this != &rhs) {
58      m_pc = rhs.m_pc;
59      m_cfa = rhs.m_cfa;
60      m_symbol_scope = rhs.m_symbol_scope;
61    }
62    return *this;
63  }
64
65protected:
66  friend class StackFrame;
67
68  void SetPC(lldb::addr_t pc) { m_pc = pc; }
69
70  void SetCFA(lldb::addr_t cfa) { m_cfa = cfa; }
71
72  lldb::addr_t
73      m_pc; // The pc value for the function/symbol for this frame. This will
74  // only get used if the symbol scope is nullptr (the code where we are
75  // stopped is not represented by any function or symbol in any shared
76  // library).
77  lldb::addr_t m_cfa; // The call frame address (stack pointer) value
78                      // at the beginning of the function that uniquely
79                      // identifies this frame (along with m_symbol_scope
80                      // below)
81  SymbolContextScope *
82      m_symbol_scope; // If nullptr, there is no block or symbol for this frame.
83                      // If not nullptr, this will either be the scope for the
84                      // lexical block for the frame, or the scope for the
85                      // symbol. Symbol context scopes are always be unique
86                      // pointers since the are part of the Block and Symbol
87                      // objects and can easily be used to tell if a stack ID
88                      // is the same as another.
89};
90
91bool operator==(const StackID &lhs, const StackID &rhs);
92bool operator!=(const StackID &lhs, const StackID &rhs);
93
94// frame_id_1 < frame_id_2 means "frame_id_1 is YOUNGER than frame_id_2"
95bool operator<(const StackID &lhs, const StackID &rhs);
96
97} // namespace lldb_private
98
99#endif // LLDB_TARGET_STACKID_H
100