1 //===-- BreakpointSite.h ----------------------------------------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 #ifndef liblldb_BreakpointSite_h_
10 #define liblldb_BreakpointSite_h_
17 #include "lldb/Breakpoint/BreakpointLocationCollection.h"
18 #include "lldb/Breakpoint/StoppointLocation.h"
19 #include "lldb/Utility/UserID.h"
20 #include "lldb/lldb-forward.h"
22 namespace lldb_private {
24 /// \class BreakpointSite BreakpointSite.h "lldb/Breakpoint/BreakpointSite.h"
25 /// Class that manages the actual breakpoint that will be inserted into the
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
35 class BreakpointSite : public std::enable_shared_from_this<BreakpointSite>,
36 public StoppointLocation {
39 eSoftware, // Breakpoint opcode has been written to memory and
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.
48 ~BreakpointSite() override;
50 // This section manages the breakpoint traps
52 /// Returns the Opcode Bytes for this breakpoint
53 uint8_t *GetTrapOpcodeBytes();
55 /// Returns the Opcode Bytes for this breakpoint - const version
56 const uint8_t *GetTrapOpcodeBytes() const;
58 /// Get the size of the trap opcode for this address
59 size_t GetTrapOpcodeMaxByteSize() const;
61 /// Sets the trap opcode
62 bool SetTrapOpcode(const uint8_t *trap_opcode, uint32_t trap_opcode_size);
64 /// Gets the original instruction bytes that were overwritten by the trap
65 uint8_t *GetSavedOpcodeBytes();
67 /// Gets the original instruction bytes that were overwritten by the trap
69 const uint8_t *GetSavedOpcodeBytes() const;
71 /// Says whether \a addr and size \a size intersects with the address \a
73 bool IntersectsRange(lldb::addr_t addr, size_t size,
74 lldb::addr_t *intersect_addr, size_t *intersect_size,
75 size_t *opcode_offset) const;
77 /// Tells whether the current breakpoint site is enabled or not
79 /// This is a low-level enable bit for the breakpoint sites. If a
80 /// breakpoint site has no enabled owners, it should just get removed. This
81 /// enable/disable is for the low-level target code to enable and disable
82 /// breakpoint sites when single stepping, etc.
83 bool IsEnabled() const;
85 /// Sets whether the current breakpoint site is enabled or not
87 /// \param[in] enabled
88 /// \b true if the breakpoint is enabled, \b false otherwise.
89 void SetEnabled(bool enabled);
91 /// Enquires of the breakpoint locations that produced this breakpoint site
92 /// whether we should stop at this location.
94 /// \param[in] context
95 /// This contains the information about this stop.
98 /// \b true if we should stop, \b false otherwise.
99 bool ShouldStop(StoppointCallbackContext *context) override;
101 /// Standard Dump method
103 /// \param[in] context
104 /// The stream to dump this output.
105 void Dump(Stream *s) const override;
107 /// The "Owners" are the breakpoint locations that share this breakpoint
108 /// site. The method adds the \a owner to this breakpoint site's owner list.
110 /// \param[in] context
111 /// \a owner is the Breakpoint Location to add.
112 void AddOwner(const lldb::BreakpointLocationSP &owner);
114 /// This method returns the number of breakpoint locations currently located
115 /// at this breakpoint site.
118 /// The number of owners.
119 size_t GetNumberOfOwners();
121 /// This method returns the breakpoint location at index \a index located at
122 /// this breakpoint site. The owners are listed ordinally from 0 to
123 /// GetNumberOfOwners() - 1 so you can use this method to iterate over the
127 /// The index in the list of owners for which you wish the owner location.
129 /// A shared pointer to the breakpoint location at that index.
130 lldb::BreakpointLocationSP GetOwnerAtIndex(size_t idx);
132 /// This method copies the breakpoint site's owners into a new collection.
133 /// It does this while the owners mutex is locked.
135 /// \param[out] out_collection
136 /// The BreakpointLocationCollection into which to put the owners
137 /// of this breakpoint site.
140 /// The number of elements copied into out_collection.
141 size_t CopyOwnersList(BreakpointLocationCollection &out_collection);
143 /// Check whether the owners of this breakpoint site have any thread
144 /// specifiers, and if yes, is \a thread contained in any of these
147 /// \param[in] thread
148 /// The thread against which to test.
151 /// \b true if the collection contains at least one location that
152 /// would be valid for this thread, false otherwise.
153 bool ValidForThisThread(Thread *thread);
155 /// Print a description of this breakpoint site to the stream \a s.
156 /// GetDescription tells you about the breakpoint site's owners. Use
157 /// BreakpointSite::Dump(Stream *) to get information about the breakpoint
161 /// The stream to which to print the description.
164 /// The description level that indicates the detail level to
167 /// \see lldb::DescriptionLevel
168 void GetDescription(Stream *s, lldb::DescriptionLevel level);
170 /// Tell whether a breakpoint has a location at this site.
173 /// The breakpoint id to query.
176 /// \b true if bp_id has a location that is at this site,
177 /// \b false otherwise.
178 bool IsBreakpointAtThisSite(lldb::break_id_t bp_id);
180 /// Tell whether ALL the breakpoints in the location collection are
184 /// \b true if all breakpoint locations are owned by internal breakpoints,
185 /// \b false otherwise.
186 bool IsInternal() const;
188 BreakpointSite::Type GetType() const { return m_type; }
190 void SetType(BreakpointSite::Type type) { m_type = type; }
193 friend class Process;
194 friend class BreakpointLocation;
195 // The StopInfoBreakpoint knows when it is processing a hit for a thread for
196 // a site, so let it be the one to manage setting the location hit count once
198 friend class StopInfoBreakpoint;
200 void BumpHitCounts();
202 /// The method removes the owner at \a break_loc_id from this breakpoint
205 /// \param[in] context
206 /// \a break_loc_id is the Breakpoint Location to remove.
207 size_t RemoveOwner(lldb::break_id_t break_id, lldb::break_id_t break_loc_id);
209 BreakpointSite::Type m_type; ///< The type of this breakpoint site.
210 uint8_t m_saved_opcode[8]; ///< The saved opcode bytes if this breakpoint site
211 ///uses trap opcodes.
212 uint8_t m_trap_opcode[8]; ///< The opcode that was used to create the
213 ///breakpoint if it is a software breakpoint site.
215 m_enabled; ///< Boolean indicating if this breakpoint site enabled or not.
217 // Consider adding an optimization where if there is only one owner, we don't
218 // store a list. The usual case will be only one owner...
219 BreakpointLocationCollection m_owners; ///< This has the BreakpointLocations
220 ///that share this breakpoint site.
222 m_owners_mutex; ///< This mutex protects the owners collection.
224 static lldb::break_id_t GetNextID();
226 // Only the Process can create breakpoint sites in
227 // Process::CreateBreakpointSite (lldb::BreakpointLocationSP &, bool).
228 BreakpointSite(BreakpointSiteList *list,
229 const lldb::BreakpointLocationSP &owner, lldb::addr_t m_addr,
232 DISALLOW_COPY_AND_ASSIGN(BreakpointSite);
235 } // namespace lldb_private
237 #endif // liblldb_BreakpointSite_h_