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ThreadPlanStepUntil.cpp
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1//===-- ThreadPlanStepUntil.cpp -------------------------------------------===//
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
10
13#include "lldb/Target/Process.h"
16#include "lldb/Target/Target.h"
18#include "lldb/Utility/Log.h"
19
20using namespace lldb;
21using namespace lldb_private;
22
23// ThreadPlanStepUntil: Run until we reach a given line number or step out of
24// the current frame
25
27 lldb::addr_t *address_list,
28 size_t num_addresses, bool stop_others,
29 uint32_t frame_idx)
30 : ThreadPlan(ThreadPlan::eKindStepUntil, "Step until", thread,
32 m_step_from_insn(LLDB_INVALID_ADDRESS),
33 m_return_bp_id(LLDB_INVALID_BREAK_ID),
34 m_return_addr(LLDB_INVALID_ADDRESS), m_stepped_out(false),
35 m_should_stop(false), m_ran_analyze(false), m_explains_stop(false),
36 m_until_points(), m_stop_others(stop_others) {
37 // Stash away our "until" addresses:
38 TargetSP target_sp(thread.CalculateTarget());
39
40 StackFrameSP frame_sp(thread.GetStackFrameAtIndex(frame_idx));
41 if (frame_sp) {
42 m_step_from_insn = frame_sp->GetStackID().GetPC();
43
44 // Find the return address and set a breakpoint there:
45 // FIXME - can we do this more securely if we know first_insn?
46
47 StackFrameSP return_frame_sp(thread.GetStackFrameAtIndex(frame_idx + 1));
48 if (return_frame_sp) {
49 // TODO: add inline functionality
50 m_return_addr = return_frame_sp->GetStackID().GetPC();
51 Breakpoint *return_bp =
52 target_sp->CreateBreakpoint(m_return_addr, true, false).get();
53
54 if (return_bp != nullptr) {
55 if (return_bp->IsHardware() && !return_bp->HasResolvedLocations())
57 return_bp->SetThreadID(m_tid);
58 m_return_bp_id = return_bp->GetID();
59 return_bp->SetBreakpointKind("until-return-backstop");
60 }
61 }
62
63 m_stack_id = frame_sp->GetStackID();
64
65 // Now set breakpoints on all our return addresses:
66 for (size_t i = 0; i < num_addresses; i++) {
67 Breakpoint *until_bp =
68 target_sp->CreateBreakpoint(address_list[i], true, false).get();
69 if (until_bp != nullptr) {
70 until_bp->SetThreadID(m_tid);
71 m_until_points[address_list[i]] = until_bp->GetID();
72 until_bp->SetBreakpointKind("until-target");
73 } else {
74 m_until_points[address_list[i]] = LLDB_INVALID_BREAK_ID;
75 }
76 }
77 }
78}
79
81
83 Target &target = GetTarget();
87 }
88
89 until_collection::iterator pos, end = m_until_points.end();
90 for (pos = m_until_points.begin(); pos != end; pos++) {
91 target.RemoveBreakpointByID((*pos).second);
92 }
93 m_until_points.clear();
95}
96
99 if (level == lldb::eDescriptionLevelBrief) {
100 s->Printf("step until");
101 if (m_stepped_out)
102 s->Printf(" - stepped out");
103 } else {
104 if (m_until_points.size() == 1)
105 s->Printf("Stepping from address 0x%" PRIx64 " until we reach 0x%" PRIx64
106 " using breakpoint %d",
107 (uint64_t)m_step_from_insn,
108 (uint64_t)(*m_until_points.begin()).first,
109 (*m_until_points.begin()).second);
110 else {
111 until_collection::iterator pos, end = m_until_points.end();
112 s->Printf("Stepping from address 0x%" PRIx64 " until we reach one of:",
113 (uint64_t)m_step_from_insn);
114 for (pos = m_until_points.begin(); pos != end; pos++) {
115 s->Printf("\n\t0x%" PRIx64 " (bp: %d)", (uint64_t)(*pos).first,
116 (*pos).second);
117 }
118 }
119 s->Printf(" stepped out address is 0x%" PRIx64 ".",
120 (uint64_t)m_return_addr);
121 }
122}
123
126 if (error)
127 error->PutCString(
128 "Could not create hardware breakpoint for thread plan.");
129 return false;
131 if (error)
132 error->PutCString("Could not create return breakpoint.");
133 return false;
134 } else {
135 until_collection::iterator pos, end = m_until_points.end();
136 for (pos = m_until_points.begin(); pos != end; pos++) {
137 if (!LLDB_BREAK_ID_IS_VALID((*pos).second))
138 return false;
139 }
140 return true;
141 }
142}
143
145 if (m_ran_analyze)
146 return;
147
148 StopInfoSP stop_info_sp = GetPrivateStopInfo();
149 m_should_stop = true;
150 m_explains_stop = false;
151
152 if (stop_info_sp) {
153 StopReason reason = stop_info_sp->GetStopReason();
154
155 if (reason == eStopReasonBreakpoint) {
156 // If this is OUR breakpoint, we're fine, otherwise we don't know why
157 // this happened...
158 BreakpointSiteSP this_site =
159 m_process.GetBreakpointSiteList().FindByID(stop_info_sp->GetValue());
160 if (!this_site) {
161 m_explains_stop = false;
162 return;
163 }
164
165 if (this_site->IsBreakpointAtThisSite(m_return_bp_id)) {
166 // If we are at our "step out" breakpoint, and the stack depth has
167 // shrunk, then this is indeed our stop. If the stack depth has grown,
168 // then we've hit our step out breakpoint recursively. If we are the
169 // only breakpoint at that location, then we do explain the stop, and
170 // we'll just continue. If there was another breakpoint here, then we
171 // don't explain the stop, but we won't mark ourselves Completed,
172 // because maybe that breakpoint will continue, and then we'll finish
173 // the "until".
174 bool done;
175 StackID cur_frame_zero_id;
176
177 done = (m_stack_id < cur_frame_zero_id);
178
179 if (done) {
180 m_stepped_out = true;
182 } else
183 m_should_stop = false;
184
185 if (this_site->GetNumberOfConstituents() == 1)
186 m_explains_stop = true;
187 else
188 m_explains_stop = false;
189 return;
190 } else {
191 // Check if we've hit one of our "until" breakpoints.
192 until_collection::iterator pos, end = m_until_points.end();
193 for (pos = m_until_points.begin(); pos != end; pos++) {
194 if (this_site->IsBreakpointAtThisSite((*pos).second)) {
195 // If we're at the right stack depth, then we're done.
196 Thread &thread = GetThread();
197 bool done;
198 StackID frame_zero_id =
199 thread.GetStackFrameAtIndex(0)->GetStackID();
200
201 if (frame_zero_id == m_stack_id)
202 done = true;
203 else if (frame_zero_id < m_stack_id)
204 done = false;
205 else {
206 StackFrameSP older_frame_sp = thread.GetStackFrameAtIndex(1);
207
208 // But if we can't even unwind one frame we should just get out
209 // of here & stop...
210 if (older_frame_sp) {
211 const SymbolContext &older_context =
212 older_frame_sp->GetSymbolContext(eSymbolContextEverything);
213 SymbolContext stack_context;
215 &stack_context);
216
217 done = (older_context == stack_context);
218 } else
219 done = false;
220 }
221
222 if (done)
224 else
225 m_should_stop = false;
226
227 // Otherwise we've hit this breakpoint recursively. If we're the
228 // only breakpoint here, then we do explain the stop, and we'll
229 // continue. If not then we should let higher plans handle this
230 // stop.
231 if (this_site->GetNumberOfConstituents() == 1)
232 m_explains_stop = true;
233 else {
234 m_should_stop = true;
235 m_explains_stop = false;
236 }
237 return;
238 }
239 }
240 }
241 // If we get here we haven't hit any of our breakpoints, so let the
242 // higher plans take care of the stop.
243 m_explains_stop = false;
244 return;
245 } else if (IsUsuallyUnexplainedStopReason(reason)) {
246 m_explains_stop = false;
247 } else {
248 m_explains_stop = true;
249 }
250 }
251}
252
254 // We don't explain signals or breakpoints (breakpoints that handle stepping
255 // in or out will be handled by a child plan.
256 AnalyzeStop();
257 return m_explains_stop;
258}
259
261 // If we've told our self in ExplainsStop that we plan to continue, then do
262 // so here. Otherwise, as long as this thread has stopped for a reason, we
263 // will stop.
264
265 StopInfoSP stop_info_sp = GetPrivateStopInfo();
266 if (!stop_info_sp || stop_info_sp->GetStopReason() == eStopReasonNone)
267 return false;
268
269 AnalyzeStop();
270 return m_should_stop;
271}
272
274
276
278 bool current_plan) {
279 if (current_plan) {
280 Target &target = GetTarget();
281 Breakpoint *return_bp = target.GetBreakpointByID(m_return_bp_id).get();
282 if (return_bp != nullptr)
283 return_bp->SetEnabled(true);
284
285 until_collection::iterator pos, end = m_until_points.end();
286 for (pos = m_until_points.begin(); pos != end; pos++) {
287 Breakpoint *until_bp = target.GetBreakpointByID((*pos).second).get();
288 if (until_bp != nullptr)
289 until_bp->SetEnabled(true);
290 }
291 }
292
293 m_should_stop = true;
294 m_ran_analyze = false;
295 m_explains_stop = false;
296 return true;
297}
298
300 Target &target = GetTarget();
301 Breakpoint *return_bp = target.GetBreakpointByID(m_return_bp_id).get();
302 if (return_bp != nullptr)
303 return_bp->SetEnabled(false);
304
305 until_collection::iterator pos, end = m_until_points.end();
306 for (pos = m_until_points.begin(); pos != end; pos++) {
307 Breakpoint *until_bp = target.GetBreakpointByID((*pos).second).get();
308 if (until_bp != nullptr)
309 until_bp->SetEnabled(false);
310 }
311 return true;
312}
313
315 // I'm letting "PlanExplainsStop" do all the work, and just reporting that
316 // here.
317 bool done = false;
318 if (IsPlanComplete()) {
319 Log *log = GetLog(LLDBLog::Step);
320 LLDB_LOGF(log, "Completed step until plan.");
321
322 Clear();
323 done = true;
324 }
325 if (done)
327
328 return done;
329}
static llvm::raw_ostream & error(Stream &strm)
#define LLDB_LOGF(log,...)
Definition: Log.h:349
General Outline: A breakpoint has four main parts, a filter, a resolver, the list of breakpoint locat...
Definition: Breakpoint.h:81
void SetBreakpointKind(const char *kind)
Set the "kind" description for a breakpoint.
Definition: Breakpoint.h:452
bool HasResolvedLocations() const
Return whether this breakpoint has any resolved locations.
Definition: Breakpoint.cpp:826
bool IsHardware() const
Definition: Breakpoint.h:520
void SetThreadID(lldb::tid_t thread_id)
Set the valid thread to be checked when the breakpoint is hit.
Definition: Breakpoint.cpp:336
void SetEnabled(bool enable) override
If enable is true, enable the breakpoint, if false disable it.
Definition: Breakpoint.cpp:285
StopPointSiteList< lldb_private::BreakpointSite > & GetBreakpointSiteList()
Definition: Process.cpp:1575
SymbolContextScope * GetSymbolContextScope() const
Definition: StackID.h:35
StopPointSiteSP FindByID(typename StopPointSite::SiteID site_id)
Returns a shared pointer to the site with id site_id.
lldb::break_id_t GetID() const
Definition: Stoppoint.cpp:22
A stream class that can stream formatted output to a file.
Definition: Stream.h:28
size_t Printf(const char *format,...) __attribute__((format(printf
Output printf formatted output to the stream.
Definition: Stream.cpp:134
virtual void CalculateSymbolContext(SymbolContext *sc)=0
Reconstruct the object's symbol context into sc.
Defines a symbol context baton that can be handed other debug core functions.
Definition: SymbolContext.h:34
lldb::BreakpointSP GetBreakpointByID(lldb::break_id_t break_id)
Definition: Target.cpp:327
bool RemoveBreakpointByID(lldb::break_id_t break_id)
Definition: Target.cpp:1003
bool DoWillResume(lldb::StateType resume_state, bool current_plan) override
void GetDescription(Stream *s, lldb::DescriptionLevel level) override
Print a description of this thread to the stream s.
bool DoPlanExplainsStop(Event *event_ptr) override
ThreadPlanStepUntil(Thread &thread, lldb::addr_t *address_list, size_t num_addresses, bool stop_others, uint32_t frame_idx=0)
bool ValidatePlan(Stream *error) override
Returns whether this plan could be successfully created.
lldb::StateType GetPlanRunState() override
bool ShouldStop(Event *event_ptr) override
bool IsUsuallyUnexplainedStopReason(lldb::StopReason)
Definition: ThreadPlan.cpp:166
void SetPlanComplete(bool success=true)
Definition: ThreadPlan.cpp:66
Thread & GetThread()
Returns the Thread that is using this thread plan.
Definition: ThreadPlan.cpp:42
virtual bool MischiefManaged()
Definition: ThreadPlan.cpp:72
lldb::StopInfoSP GetPrivateStopInfo()
Definition: ThreadPlan.h:517
virtual lldb::StackFrameSP GetStackFrameAtIndex(uint32_t idx)
Definition: Thread.h:405
lldb::TargetSP CalculateTarget() override
Definition: Thread.cpp:1390
#define LLDB_INVALID_BREAK_ID
Definition: lldb-defines.h:37
#define LLDB_BREAK_ID_IS_VALID(bid)
Definition: lldb-defines.h:39
#define LLDB_INVALID_ADDRESS
Definition: lldb-defines.h:82
A class that represents a running process on the host machine.
Definition: SBAttachInfo.h:14
Log * GetLog(Cat mask)
Retrieve the Log object for the channel associated with the given log enum.
Definition: Log.h:314
Definition: SBAddress.h:15
std::shared_ptr< lldb_private::StackFrame > StackFrameSP
Definition: lldb-forward.h:412
std::shared_ptr< lldb_private::BreakpointSite > BreakpointSiteSP
Definition: lldb-forward.h:315
DescriptionLevel
Description levels for "void GetDescription(Stream *, DescriptionLevel)" calls.
@ eDescriptionLevelBrief
StateType
Process and Thread States.
@ eStateRunning
Process or thread is running and can't be examined.
std::shared_ptr< lldb_private::StopInfo > StopInfoSP
Definition: lldb-forward.h:419
uint64_t addr_t
Definition: lldb-types.h:79
StopReason
Thread stop reasons.
@ eStopReasonBreakpoint
std::shared_ptr< lldb_private::Target > TargetSP
Definition: lldb-forward.h:436