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BreakpointSite.h
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1//===-- BreakpointSite.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_BREAKPOINT_BREAKPOINTSITE_H
10#define LLDB_BREAKPOINT_BREAKPOINTSITE_H
11
12#include <list>
13#include <mutex>
14
15
19#include "lldb/Utility/UserID.h"
20#include "lldb/lldb-forward.h"
21
22namespace lldb_private {
23
24/// \class BreakpointSite BreakpointSite.h "lldb/Breakpoint/BreakpointSite.h"
25/// Class that manages the actual breakpoint that will be inserted into the
26/// running program.
27///
28/// The BreakpointSite class handles the physical breakpoint that is actually
29/// inserted in the target program. As such, it is also the one that gets
30/// hit, when the program stops. It keeps a list of all BreakpointLocations
31/// that share this physical site. When the breakpoint is hit, all the
32/// locations are informed by the breakpoint site. Breakpoint sites are owned
33/// by the process.
34
35class BreakpointSite : public std::enable_shared_from_this<BreakpointSite>,
36 public StoppointSite {
37public:
38 enum Type {
39 eSoftware, // Breakpoint opcode has been written to memory and
40 // m_saved_opcode
41 // and m_trap_opcode contain the saved and written opcode.
42 eHardware, // Breakpoint site is set as a hardware breakpoint
43 eExternal // Breakpoint site is managed by an external debug nub or
44 // debug interface where memory reads transparently will not
45 // display any breakpoint opcodes.
46 };
47
50
51 ~BreakpointSite() override;
52
53 // This section manages the breakpoint traps
54
55 /// Returns the Opcode Bytes for this breakpoint
56 uint8_t *GetTrapOpcodeBytes();
57
58 /// Returns the Opcode Bytes for this breakpoint - const version
59 const uint8_t *GetTrapOpcodeBytes() const;
60
61 /// Get the size of the trap opcode for this address
62 size_t GetTrapOpcodeMaxByteSize() const;
63
64 /// Sets the trap opcode
65 bool SetTrapOpcode(const uint8_t *trap_opcode, uint32_t trap_opcode_size);
66
67 /// Gets the original instruction bytes that were overwritten by the trap
68 uint8_t *GetSavedOpcodeBytes();
69
70 /// Gets the original instruction bytes that were overwritten by the trap
71 /// const version
72 const uint8_t *GetSavedOpcodeBytes() const;
73
74 /// Says whether \a addr and size \a size intersects with the address \a
75 /// intersect_addr
76 bool IntersectsRange(lldb::addr_t addr, size_t size,
77 lldb::addr_t *intersect_addr, size_t *intersect_size,
78 size_t *opcode_offset) const;
79
80 /// Tells whether the current breakpoint site is enabled or not
81 ///
82 /// This is a low-level enable bit for the breakpoint sites. If a
83 /// breakpoint site has no enabled constituents, it should just get removed.
84 /// This enable/disable is for the low-level target code to enable and disable
85 /// breakpoint sites when single stepping, etc.
86 bool IsEnabled() const;
87
88 /// Sets whether the current breakpoint site is enabled or not
89 ///
90 /// \param[in] enabled
91 /// \b true if the breakpoint is enabled, \b false otherwise.
92 void SetEnabled(bool enabled);
93
94 /// Enquires of the breakpoint locations that produced this breakpoint site
95 /// whether we should stop at this location.
96 ///
97 /// \param[in] context
98 /// This contains the information about this stop.
99 ///
100 /// \return
101 /// \b true if we should stop, \b false otherwise.
102 bool ShouldStop(StoppointCallbackContext *context) override;
103
104 /// Standard Dump method
105 void Dump(Stream *s) const override;
106
107 /// The "Constituents" are the breakpoint locations that share this breakpoint
108 /// site. The method adds the \a constituent to this breakpoint site's
109 /// constituent list.
110 ///
111 /// \param[in] constituent
112 /// \a constituent is the Breakpoint Location to add.
113 void AddConstituent(const lldb::BreakpointLocationSP &constituent);
114
115 /// This method returns the number of breakpoint locations currently located
116 /// at this breakpoint site.
117 ///
118 /// \return
119 /// The number of constituents.
121
122 /// This method returns the breakpoint location at index \a index located at
123 /// this breakpoint site. The constituents are listed ordinally from 0 to
124 /// GetNumberOfConstituents() - 1 so you can use this method to iterate over
125 /// the constituents
126 ///
127 /// \param[in] idx
128 /// The index in the list of constituents for which you wish the
129 /// constituent location.
130 ///
131 /// \return
132 /// A shared pointer to the breakpoint location at that index.
134
135 /// This method copies the breakpoint site's constituents into a new
136 /// collection. It does this while the constituents mutex is locked.
137 ///
138 /// \param[out] out_collection
139 /// The BreakpointLocationCollection into which to put the constituents
140 /// of this breakpoint site.
141 ///
142 /// \return
143 /// The number of elements copied into out_collection.
145
146 /// Check whether the constituents of this breakpoint site have any thread
147 /// specifiers, and if yes, is \a thread contained in any of these
148 /// specifiers.
149 ///
150 /// \param[in] thread
151 /// The thread against which to test.
152 ///
153 /// return
154 /// \b true if the collection contains at least one location that
155 /// would be valid for this thread, false otherwise.
156 bool ValidForThisThread(Thread &thread);
157
158 /// Print a description of this breakpoint site to the stream \a s.
159 /// GetDescription tells you about the breakpoint site's constituents. Use
160 /// BreakpointSite::Dump(Stream *) to get information about the breakpoint
161 /// site itself.
162 ///
163 /// \param[in] s
164 /// The stream to which to print the description.
165 ///
166 /// \param[in] level
167 /// The description level that indicates the detail level to
168 /// provide.
169 ///
170 /// \see lldb::DescriptionLevel
172
173 /// Tell whether a breakpoint has a location at this site.
174 ///
175 /// \param[in] bp_id
176 /// The breakpoint id to query.
177 ///
178 /// \result
179 /// \b true if bp_id has a location that is at this site,
180 /// \b false otherwise.
182
183 /// Tell whether ALL the breakpoints in the location collection are
184 /// internal.
185 ///
186 /// \result
187 /// \b true if all breakpoint locations are owned by internal breakpoints,
188 /// \b false otherwise.
189 bool IsInternal() const;
190
191 bool IsHardware() const override {
195 }
196
198
199 void SetType(BreakpointSite::Type type) { m_type = type; }
200
201private:
202 friend class Process;
203 friend class BreakpointLocation;
204 // The StopInfoBreakpoint knows when it is processing a hit for a thread for
205 // a site, so let it be the one to manage setting the location hit count once
206 // and only once.
207 friend class StopInfoBreakpoint;
208
209 void BumpHitCounts();
210
211 /// The method removes the constituent at \a break_loc_id from this breakpoint
212 /// list.
213 size_t RemoveConstituent(lldb::break_id_t break_id,
214 lldb::break_id_t break_loc_id);
215
216 BreakpointSite::Type m_type; ///< The type of this breakpoint site.
217 uint8_t m_saved_opcode[8]; ///< The saved opcode bytes if this breakpoint site
218 ///uses trap opcodes.
219 uint8_t m_trap_opcode[8]; ///< The opcode that was used to create the
220 ///breakpoint if it is a software breakpoint site.
221 bool
222 m_enabled; ///< Boolean indicating if this breakpoint site enabled or not.
223
224 // Consider adding an optimization where if there is only one constituent, we
225 // don't store a list. The usual case will be only one constituent...
227 m_constituents; ///< This has the BreakpointLocations
228 /// that share this breakpoint site.
229 std::recursive_mutex m_constituents_mutex; ///< This mutex protects the
230 ///< constituents collection.
231
233
234 // Only the Process can create breakpoint sites in
235 // Process::CreateBreakpointSite (lldb::BreakpointLocationSP &, bool).
237 lldb::addr_t m_addr, bool use_hardware);
238
240 const BreakpointSite &operator=(const BreakpointSite &) = delete;
241};
242
243} // namespace lldb_private
244
245#endif // LLDB_BREAKPOINT_BREAKPOINTSITE_H
#define lldbassert(x)
Definition: LLDBAssert.h:15
General Outline: A breakpoint location is defined by the breakpoint that produces it,...
Class that manages the actual breakpoint that will be inserted into the running program.
BreakpointLocationCollection m_constituents
This has the BreakpointLocations that share this breakpoint site.
bool SetTrapOpcode(const uint8_t *trap_opcode, uint32_t trap_opcode_size)
Sets the trap opcode.
static lldb::break_id_t GetNextID()
void Dump(Stream *s) const override
Standard Dump method.
bool ShouldStop(StoppointCallbackContext *context) override
Enquires of the breakpoint locations that produced this breakpoint site whether we should stop at thi...
const BreakpointSite & operator=(const BreakpointSite &)=delete
size_t GetTrapOpcodeMaxByteSize() const
Get the size of the trap opcode for this address.
size_t GetNumberOfConstituents()
This method returns the number of breakpoint locations currently located at this breakpoint site.
BreakpointSite::Type m_type
The type of this breakpoint site.
BreakpointSite::Type GetType() const
void SetType(BreakpointSite::Type type)
std::recursive_mutex m_constituents_mutex
This mutex protects the constituents collection.
bool IntersectsRange(lldb::addr_t addr, size_t size, lldb::addr_t *intersect_addr, size_t *intersect_size, size_t *opcode_offset) const
Says whether addr and size size intersects with the address intersect_addr.
bool IsBreakpointAtThisSite(lldb::break_id_t bp_id)
Tell whether a breakpoint has a location at this site.
void AddConstituent(const lldb::BreakpointLocationSP &constituent)
The "Constituents" are the breakpoint locations that share this breakpoint site.
uint8_t * GetTrapOpcodeBytes()
Returns the Opcode Bytes for this breakpoint.
bool IsInternal() const
Tell whether ALL the breakpoints in the location collection are internal.
bool ValidForThisThread(Thread &thread)
Check whether the constituents of this breakpoint site have any thread specifiers,...
void GetDescription(Stream *s, lldb::DescriptionLevel level)
Print a description of this breakpoint site to the stream s.
uint8_t m_trap_opcode[8]
The opcode that was used to create the breakpoint if it is a software breakpoint site.
size_t RemoveConstituent(lldb::break_id_t break_id, lldb::break_id_t break_loc_id)
The method removes the constituent at break_loc_id from this breakpoint list.
uint8_t * GetSavedOpcodeBytes()
Gets the original instruction bytes that were overwritten by the trap.
BreakpointSite(const BreakpointSite &)=delete
lldb::BreakpointLocationSP GetConstituentAtIndex(size_t idx)
This method returns the breakpoint location at index index located at this breakpoint site.
bool IsHardware() const override
bool m_enabled
Boolean indicating if this breakpoint site enabled or not.
uint8_t m_saved_opcode[8]
The saved opcode bytes if this breakpoint site uses trap opcodes.
bool IsEnabled() const
Tells whether the current breakpoint site is enabled or not.
lldb::break_id_t ConstituentID
size_t CopyConstituentsList(BreakpointLocationCollection &out_collection)
This method copies the breakpoint site's constituents into a new collection.
void SetEnabled(bool enabled)
Sets whether the current breakpoint site is enabled or not.
A plug-in interface definition class for debugging a process.
Definition: Process.h:341
General Outline: When we hit a breakpoint we need to package up whatever information is needed to eva...
lldb::addr_t m_addr
The load address of this stop point.
Definition: StoppointSite.h:52
A stream class that can stream formatted output to a file.
Definition: Stream.h:28
A class that represents a running process on the host machine.
Definition: SBAttachInfo.h:14
std::shared_ptr< lldb_private::BreakpointLocation > BreakpointLocationSP
Definition: lldb-forward.h:316
DescriptionLevel
Description levels for "void GetDescription(Stream *, DescriptionLevel)" calls.
int32_t break_id_t
Definition: lldb-types.h:86
uint64_t addr_t
Definition: lldb-types.h:80