1 //===-- ThreadPlanStepUntil.cpp ---------------------------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //m_should_stop
10
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "lldb/Target/ThreadPlanStepUntil.h"
15
16 // C Includes
17 // C++ Includes
18 // Other libraries and framework includes
19 // Project includes
20 #include "lldb/Breakpoint/Breakpoint.h"
21 #include "lldb/lldb-private-log.h"
22 #include "lldb/Core/Log.h"
23 #include "lldb/Target/Process.h"
24 #include "lldb/Target/RegisterContext.h"
25 #include "lldb/Target/StopInfo.h"
26 #include "lldb/Target/Target.h"
27
28 using namespace lldb;
29 using namespace lldb_private;
30
31 //----------------------------------------------------------------------
32 // ThreadPlanStepUntil: Run until we reach a given line number or step out of the current frame
33 //----------------------------------------------------------------------
34
ThreadPlanStepUntil(Thread & thread,lldb::addr_t * address_list,size_t num_addresses,bool stop_others,uint32_t frame_idx)35 ThreadPlanStepUntil::ThreadPlanStepUntil
36 (
37 Thread &thread,
38 lldb::addr_t *address_list,
39 size_t num_addresses,
40 bool stop_others,
41 uint32_t frame_idx
42 ) :
43 ThreadPlan (ThreadPlan::eKindStepUntil, "Step until", thread, eVoteNoOpinion, eVoteNoOpinion),
44 m_step_from_insn (LLDB_INVALID_ADDRESS),
45 m_return_bp_id (LLDB_INVALID_BREAK_ID),
46 m_return_addr (LLDB_INVALID_ADDRESS),
47 m_stepped_out (false),
48 m_should_stop (false),
49 m_ran_analyze (false),
50 m_explains_stop (false),
51 m_until_points (),
52 m_stop_others (stop_others)
53 {
54 // Stash away our "until" addresses:
55 TargetSP target_sp (m_thread.CalculateTarget());
56
57 StackFrameSP frame_sp (m_thread.GetStackFrameAtIndex (frame_idx));
58 if (frame_sp)
59 {
60 m_step_from_insn = frame_sp->GetStackID().GetPC();
61 lldb::user_id_t thread_id = m_thread.GetID();
62
63 // Find the return address and set a breakpoint there:
64 // FIXME - can we do this more securely if we know first_insn?
65
66 StackFrameSP return_frame_sp (m_thread.GetStackFrameAtIndex(frame_idx + 1));
67 if (return_frame_sp)
68 {
69 // TODO: add inline functionality
70 m_return_addr = return_frame_sp->GetStackID().GetPC();
71 Breakpoint *return_bp = target_sp->CreateBreakpoint (m_return_addr, true).get();
72 if (return_bp != NULL)
73 {
74 return_bp->SetThreadID(thread_id);
75 m_return_bp_id = return_bp->GetID();
76 return_bp->SetBreakpointKind ("until-return-backstop");
77 }
78 }
79
80 m_stack_id = m_thread.GetStackFrameAtIndex(frame_idx)->GetStackID();
81
82 // Now set breakpoints on all our return addresses:
83 for (size_t i = 0; i < num_addresses; i++)
84 {
85 Breakpoint *until_bp = target_sp->CreateBreakpoint (address_list[i], true).get();
86 if (until_bp != NULL)
87 {
88 until_bp->SetThreadID(thread_id);
89 m_until_points[address_list[i]] = until_bp->GetID();
90 until_bp->SetBreakpointKind("until-target");
91 }
92 else
93 {
94 m_until_points[address_list[i]] = LLDB_INVALID_BREAK_ID;
95 }
96 }
97 }
98 }
99
~ThreadPlanStepUntil()100 ThreadPlanStepUntil::~ThreadPlanStepUntil ()
101 {
102 Clear();
103 }
104
105 void
Clear()106 ThreadPlanStepUntil::Clear()
107 {
108 TargetSP target_sp (m_thread.CalculateTarget());
109 if (target_sp)
110 {
111 if (m_return_bp_id != LLDB_INVALID_BREAK_ID)
112 {
113 target_sp->RemoveBreakpointByID(m_return_bp_id);
114 m_return_bp_id = LLDB_INVALID_BREAK_ID;
115 }
116
117 until_collection::iterator pos, end = m_until_points.end();
118 for (pos = m_until_points.begin(); pos != end; pos++)
119 {
120 target_sp->RemoveBreakpointByID((*pos).second);
121 }
122 }
123 m_until_points.clear();
124 }
125
126 void
GetDescription(Stream * s,lldb::DescriptionLevel level)127 ThreadPlanStepUntil::GetDescription (Stream *s, lldb::DescriptionLevel level)
128 {
129 if (level == lldb::eDescriptionLevelBrief)
130 {
131 s->Printf ("step until");
132 if (m_stepped_out)
133 s->Printf (" - stepped out");
134 }
135 else
136 {
137 if (m_until_points.size() == 1)
138 s->Printf ("Stepping from address 0x%" PRIx64 " until we reach 0x%" PRIx64 " using breakpoint %d",
139 (uint64_t)m_step_from_insn,
140 (uint64_t) (*m_until_points.begin()).first,
141 (*m_until_points.begin()).second);
142 else
143 {
144 until_collection::iterator pos, end = m_until_points.end();
145 s->Printf ("Stepping from address 0x%" PRIx64 " until we reach one of:",
146 (uint64_t)m_step_from_insn);
147 for (pos = m_until_points.begin(); pos != end; pos++)
148 {
149 s->Printf ("\n\t0x%" PRIx64 " (bp: %d)", (uint64_t) (*pos).first, (*pos).second);
150 }
151 }
152 s->Printf(" stepped out address is 0x%" PRIx64 ".", (uint64_t) m_return_addr);
153 }
154 }
155
156 bool
ValidatePlan(Stream * error)157 ThreadPlanStepUntil::ValidatePlan (Stream *error)
158 {
159 if (m_return_bp_id == LLDB_INVALID_BREAK_ID)
160 return false;
161 else
162 {
163 until_collection::iterator pos, end = m_until_points.end();
164 for (pos = m_until_points.begin(); pos != end; pos++)
165 {
166 if (!LLDB_BREAK_ID_IS_VALID ((*pos).second))
167 return false;
168 }
169 return true;
170 }
171 }
172
173 void
AnalyzeStop()174 ThreadPlanStepUntil::AnalyzeStop()
175 {
176 if (m_ran_analyze)
177 return;
178
179 StopInfoSP stop_info_sp = GetPrivateStopInfo ();
180 m_should_stop = true;
181 m_explains_stop = false;
182
183 if (stop_info_sp)
184 {
185 StopReason reason = stop_info_sp->GetStopReason();
186
187 switch (reason)
188 {
189 case eStopReasonBreakpoint:
190 {
191 // If this is OUR breakpoint, we're fine, otherwise we don't know why this happened...
192 BreakpointSiteSP this_site = m_thread.GetProcess()->GetBreakpointSiteList().FindByID (stop_info_sp->GetValue());
193 if (!this_site)
194 {
195 m_explains_stop = false;
196 return;
197 }
198
199 if (this_site->IsBreakpointAtThisSite (m_return_bp_id))
200 {
201 // If we are at our "step out" breakpoint, and the stack depth has shrunk, then
202 // this is indeed our stop.
203 // If the stack depth has grown, then we've hit our step out breakpoint recursively.
204 // If we are the only breakpoint at that location, then we do explain the stop, and
205 // we'll just continue.
206 // If there was another breakpoint here, then we don't explain the stop, but we won't
207 // mark ourselves Completed, because maybe that breakpoint will continue, and then
208 // we'll finish the "until".
209 bool done;
210 StackID cur_frame_zero_id;
211
212 if (m_stack_id < cur_frame_zero_id)
213 done = true;
214 else
215 done = false;
216
217 if (done)
218 {
219 m_stepped_out = true;
220 SetPlanComplete();
221 }
222 else
223 m_should_stop = false;
224
225 if (this_site->GetNumberOfOwners() == 1)
226 m_explains_stop = true;
227 else
228 m_explains_stop = false;
229 return;
230 }
231 else
232 {
233 // Check if we've hit one of our "until" breakpoints.
234 until_collection::iterator pos, end = m_until_points.end();
235 for (pos = m_until_points.begin(); pos != end; pos++)
236 {
237 if (this_site->IsBreakpointAtThisSite ((*pos).second))
238 {
239 // If we're at the right stack depth, then we're done.
240
241 bool done;
242 StackID frame_zero_id = m_thread.GetStackFrameAtIndex(0)->GetStackID();
243
244 if (frame_zero_id == m_stack_id)
245 done = true;
246 else if (frame_zero_id < m_stack_id)
247 done = false;
248 else
249 {
250 StackFrameSP older_frame_sp = m_thread.GetStackFrameAtIndex(1);
251
252 // But if we can't even unwind one frame we should just get out of here & stop...
253 if (older_frame_sp)
254 {
255 const SymbolContext &older_context
256 = older_frame_sp->GetSymbolContext(eSymbolContextEverything);
257 SymbolContext stack_context;
258 m_stack_id.GetSymbolContextScope()->CalculateSymbolContext(&stack_context);
259
260 if (older_context == stack_context)
261 done = true;
262 else
263 done = false;
264 }
265 else
266 done = false;
267 }
268
269 if (done)
270 SetPlanComplete();
271 else
272 m_should_stop = false;
273
274 // Otherwise we've hit this breakpoint recursively. If we're the
275 // only breakpoint here, then we do explain the stop, and we'll continue.
276 // If not then we should let higher plans handle this stop.
277 if (this_site->GetNumberOfOwners() == 1)
278 m_explains_stop = true;
279 else
280 {
281 m_should_stop = true;
282 m_explains_stop = false;
283 }
284 return;
285 }
286 }
287 }
288 // If we get here we haven't hit any of our breakpoints, so let the higher
289 // plans take care of the stop.
290 m_explains_stop = false;
291 return;
292 }
293 case eStopReasonWatchpoint:
294 case eStopReasonSignal:
295 case eStopReasonException:
296 case eStopReasonExec:
297 case eStopReasonThreadExiting:
298 m_explains_stop = false;
299 break;
300 default:
301 m_explains_stop = true;
302 break;
303 }
304 }
305 }
306
307 bool
DoPlanExplainsStop(Event * event_ptr)308 ThreadPlanStepUntil::DoPlanExplainsStop (Event *event_ptr)
309 {
310 // We don't explain signals or breakpoints (breakpoints that handle stepping in or
311 // out will be handled by a child plan.
312 AnalyzeStop();
313 return m_explains_stop;
314 }
315
316 bool
ShouldStop(Event * event_ptr)317 ThreadPlanStepUntil::ShouldStop (Event *event_ptr)
318 {
319 // If we've told our self in ExplainsStop that we plan to continue, then
320 // do so here. Otherwise, as long as this thread has stopped for a reason,
321 // we will stop.
322
323 StopInfoSP stop_info_sp = GetPrivateStopInfo ();
324 if (!stop_info_sp || stop_info_sp->GetStopReason() == eStopReasonNone)
325 return false;
326
327 AnalyzeStop();
328 return m_should_stop;
329 }
330
331 bool
StopOthers()332 ThreadPlanStepUntil::StopOthers ()
333 {
334 return m_stop_others;
335 }
336
337 StateType
GetPlanRunState()338 ThreadPlanStepUntil::GetPlanRunState ()
339 {
340 return eStateRunning;
341 }
342
343 bool
DoWillResume(StateType resume_state,bool current_plan)344 ThreadPlanStepUntil::DoWillResume (StateType resume_state, bool current_plan)
345 {
346 if (current_plan)
347 {
348 TargetSP target_sp (m_thread.CalculateTarget());
349 if (target_sp)
350 {
351 Breakpoint *return_bp = target_sp->GetBreakpointByID(m_return_bp_id).get();
352 if (return_bp != NULL)
353 return_bp->SetEnabled (true);
354
355 until_collection::iterator pos, end = m_until_points.end();
356 for (pos = m_until_points.begin(); pos != end; pos++)
357 {
358 Breakpoint *until_bp = target_sp->GetBreakpointByID((*pos).second).get();
359 if (until_bp != NULL)
360 until_bp->SetEnabled (true);
361 }
362 }
363 }
364
365 m_should_stop = true;
366 m_ran_analyze = false;
367 m_explains_stop = false;
368 return true;
369 }
370
371 bool
WillStop()372 ThreadPlanStepUntil::WillStop ()
373 {
374 TargetSP target_sp (m_thread.CalculateTarget());
375 if (target_sp)
376 {
377 Breakpoint *return_bp = target_sp->GetBreakpointByID(m_return_bp_id).get();
378 if (return_bp != NULL)
379 return_bp->SetEnabled (false);
380
381 until_collection::iterator pos, end = m_until_points.end();
382 for (pos = m_until_points.begin(); pos != end; pos++)
383 {
384 Breakpoint *until_bp = target_sp->GetBreakpointByID((*pos).second).get();
385 if (until_bp != NULL)
386 until_bp->SetEnabled (false);
387 }
388 }
389 return true;
390 }
391
392 bool
MischiefManaged()393 ThreadPlanStepUntil::MischiefManaged ()
394 {
395
396 // I'm letting "PlanExplainsStop" do all the work, and just reporting that here.
397 bool done = false;
398 if (IsPlanComplete())
399 {
400 Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
401 if (log)
402 log->Printf("Completed step until plan.");
403
404 Clear();
405 done = true;
406 }
407 if (done)
408 ThreadPlan::MischiefManaged ();
409
410 return done;
411
412 }
413
414