1 //===-- Thread.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 
10 // C Includes
11 // C++ Includes
12 // Other libraries and framework includes
13 // Project includes
14 #include "lldb/Breakpoint/BreakpointLocation.h"
15 #include "lldb/Core/Debugger.h"
16 #include "lldb/Core/Log.h"
17 #include "lldb/Core/FormatEntity.h"
18 #include "lldb/Core/Module.h"
19 #include "lldb/Core/State.h"
20 #include "lldb/Core/Stream.h"
21 #include "lldb/Core/StreamString.h"
22 #include "lldb/Core/RegularExpression.h"
23 #include "lldb/Core/ValueObject.h"
24 #include "lldb/Host/Host.h"
25 #include "lldb/Interpreter/OptionValueFileSpecList.h"
26 #include "lldb/Interpreter/OptionValueProperties.h"
27 #include "lldb/Interpreter/Property.h"
28 #include "lldb/Symbol/Function.h"
29 #include "lldb/Target/ABI.h"
30 #include "lldb/Target/DynamicLoader.h"
31 #include "lldb/Target/ExecutionContext.h"
32 #include "lldb/Target/Process.h"
33 #include "lldb/Target/RegisterContext.h"
34 #include "lldb/Target/StopInfo.h"
35 #include "lldb/Target/SystemRuntime.h"
36 #include "lldb/Target/Target.h"
37 #include "lldb/Target/Thread.h"
38 #include "lldb/Target/ThreadPlan.h"
39 #include "lldb/Target/ThreadPlanCallFunction.h"
40 #include "lldb/Target/ThreadPlanBase.h"
41 #include "lldb/Target/ThreadPlanPython.h"
42 #include "lldb/Target/ThreadPlanStepInstruction.h"
43 #include "lldb/Target/ThreadPlanStepOut.h"
44 #include "lldb/Target/ThreadPlanStepOverBreakpoint.h"
45 #include "lldb/Target/ThreadPlanStepThrough.h"
46 #include "lldb/Target/ThreadPlanStepInRange.h"
47 #include "lldb/Target/ThreadPlanStepOverRange.h"
48 #include "lldb/Target/ThreadPlanRunToAddress.h"
49 #include "lldb/Target/ThreadPlanStepUntil.h"
50 #include "lldb/Target/ThreadSpec.h"
51 #include "lldb/Target/Unwind.h"
52 #include "Plugins/Process/Utility/UnwindLLDB.h"
53 #include "Plugins/Process/Utility/UnwindMacOSXFrameBackchain.h"
54 
55 using namespace lldb;
56 using namespace lldb_private;
57 
58 const ThreadPropertiesSP &
59 Thread::GetGlobalProperties()
60 {
61     static ThreadPropertiesSP g_settings_sp;
62     if (!g_settings_sp)
63         g_settings_sp.reset (new ThreadProperties (true));
64     return g_settings_sp;
65 }
66 
67 static PropertyDefinition
68 g_properties[] =
69 {
70     { "step-in-avoid-nodebug", OptionValue::eTypeBoolean, true, true, nullptr, nullptr, "If true, step-in will not stop in functions with no debug information." },
71     { "step-out-avoid-nodebug", OptionValue::eTypeBoolean, true, false, nullptr, nullptr, "If true, when step-in/step-out/step-over leave the current frame, they will continue to step out till they come to a function with "
72                                                                                     "debug information.  Passing a frame argument to step-out will override this option." },
73     { "step-avoid-regexp",  OptionValue::eTypeRegex  , true , 0, "^std::", nullptr, "A regular expression defining functions step-in won't stop in." },
74     { "step-avoid-libraries",  OptionValue::eTypeFileSpecList  , true , 0, nullptr, nullptr, "A list of libraries that source stepping won't stop in." },
75     { "trace-thread",       OptionValue::eTypeBoolean, false, false, nullptr, nullptr, "If true, this thread will single-step and log execution." },
76     {  nullptr               , OptionValue::eTypeInvalid, false, 0    , nullptr, nullptr, nullptr  }
77 };
78 
79 enum {
80     ePropertyStepInAvoidsNoDebug,
81     ePropertyStepOutAvoidsNoDebug,
82     ePropertyStepAvoidRegex,
83     ePropertyStepAvoidLibraries,
84     ePropertyEnableThreadTrace
85 };
86 
87 class ThreadOptionValueProperties : public OptionValueProperties
88 {
89 public:
90     ThreadOptionValueProperties (const ConstString &name) :
91         OptionValueProperties (name)
92     {
93     }
94 
95     // This constructor is used when creating ThreadOptionValueProperties when it
96     // is part of a new lldb_private::Thread instance. It will copy all current
97     // global property values as needed
98     ThreadOptionValueProperties (ThreadProperties *global_properties) :
99         OptionValueProperties(*global_properties->GetValueProperties())
100     {
101     }
102 
103     const Property *
104     GetPropertyAtIndex(const ExecutionContext *exe_ctx, bool will_modify, uint32_t idx) const override
105     {
106         // When getting the value for a key from the thread options, we will always
107         // try and grab the setting from the current thread if there is one. Else we just
108         // use the one from this instance.
109         if (exe_ctx)
110         {
111             Thread *thread = exe_ctx->GetThreadPtr();
112             if (thread)
113             {
114                 ThreadOptionValueProperties *instance_properties = static_cast<ThreadOptionValueProperties *>(thread->GetValueProperties().get());
115                 if (this != instance_properties)
116                     return instance_properties->ProtectedGetPropertyAtIndex (idx);
117             }
118         }
119         return ProtectedGetPropertyAtIndex (idx);
120     }
121 };
122 
123 ThreadProperties::ThreadProperties (bool is_global) :
124     Properties ()
125 {
126     if (is_global)
127     {
128         m_collection_sp.reset (new ThreadOptionValueProperties(ConstString("thread")));
129         m_collection_sp->Initialize(g_properties);
130     }
131     else
132         m_collection_sp.reset (new ThreadOptionValueProperties(Thread::GetGlobalProperties().get()));
133 }
134 
135 ThreadProperties::~ThreadProperties() = default;
136 
137 const RegularExpression *
138 ThreadProperties::GetSymbolsToAvoidRegexp()
139 {
140     const uint32_t idx = ePropertyStepAvoidRegex;
141     return m_collection_sp->GetPropertyAtIndexAsOptionValueRegex(nullptr, idx);
142 }
143 
144 FileSpecList &
145 ThreadProperties::GetLibrariesToAvoid() const
146 {
147     const uint32_t idx = ePropertyStepAvoidLibraries;
148     OptionValueFileSpecList *option_value = m_collection_sp->GetPropertyAtIndexAsOptionValueFileSpecList(nullptr, false, idx);
149     assert(option_value);
150     return option_value->GetCurrentValue();
151 }
152 
153 bool
154 ThreadProperties::GetTraceEnabledState() const
155 {
156     const uint32_t idx = ePropertyEnableThreadTrace;
157     return m_collection_sp->GetPropertyAtIndexAsBoolean(nullptr, idx, g_properties[idx].default_uint_value != 0);
158 }
159 
160 bool
161 ThreadProperties::GetStepInAvoidsNoDebug() const
162 {
163     const uint32_t idx = ePropertyStepInAvoidsNoDebug;
164     return m_collection_sp->GetPropertyAtIndexAsBoolean(nullptr, idx, g_properties[idx].default_uint_value != 0);
165 }
166 
167 bool
168 ThreadProperties::GetStepOutAvoidsNoDebug() const
169 {
170     const uint32_t idx = ePropertyStepOutAvoidsNoDebug;
171     return m_collection_sp->GetPropertyAtIndexAsBoolean(nullptr, idx, g_properties[idx].default_uint_value != 0);
172 }
173 
174 //------------------------------------------------------------------
175 // Thread Event Data
176 //------------------------------------------------------------------
177 
178 const ConstString &
179 Thread::ThreadEventData::GetFlavorString ()
180 {
181     static ConstString g_flavor ("Thread::ThreadEventData");
182     return g_flavor;
183 }
184 
185 Thread::ThreadEventData::ThreadEventData (const lldb::ThreadSP thread_sp) :
186     m_thread_sp (thread_sp),
187     m_stack_id ()
188 {
189 }
190 
191 Thread::ThreadEventData::ThreadEventData (const lldb::ThreadSP thread_sp, const StackID &stack_id) :
192     m_thread_sp (thread_sp),
193     m_stack_id (stack_id)
194 {
195 }
196 
197 Thread::ThreadEventData::ThreadEventData () :
198     m_thread_sp (),
199     m_stack_id ()
200 {
201 }
202 
203 Thread::ThreadEventData::~ThreadEventData() = default;
204 
205 void
206 Thread::ThreadEventData::Dump (Stream *s) const
207 {
208 }
209 
210 const Thread::ThreadEventData *
211 Thread::ThreadEventData::GetEventDataFromEvent (const Event *event_ptr)
212 {
213     if (event_ptr)
214     {
215         const EventData *event_data = event_ptr->GetData();
216         if (event_data && event_data->GetFlavor() == ThreadEventData::GetFlavorString())
217             return static_cast <const ThreadEventData *> (event_ptr->GetData());
218     }
219     return nullptr;
220 }
221 
222 ThreadSP
223 Thread::ThreadEventData::GetThreadFromEvent (const Event *event_ptr)
224 {
225     ThreadSP thread_sp;
226     const ThreadEventData *event_data = GetEventDataFromEvent (event_ptr);
227     if (event_data)
228         thread_sp = event_data->GetThread();
229     return thread_sp;
230 }
231 
232 StackID
233 Thread::ThreadEventData::GetStackIDFromEvent (const Event *event_ptr)
234 {
235     StackID stack_id;
236     const ThreadEventData *event_data = GetEventDataFromEvent (event_ptr);
237     if (event_data)
238         stack_id = event_data->GetStackID();
239     return stack_id;
240 }
241 
242 StackFrameSP
243 Thread::ThreadEventData::GetStackFrameFromEvent (const Event *event_ptr)
244 {
245     const ThreadEventData *event_data = GetEventDataFromEvent (event_ptr);
246     StackFrameSP frame_sp;
247     if (event_data)
248     {
249         ThreadSP thread_sp = event_data->GetThread();
250         if (thread_sp)
251         {
252             frame_sp = thread_sp->GetStackFrameList()->GetFrameWithStackID (event_data->GetStackID());
253         }
254     }
255     return frame_sp;
256 }
257 
258 //------------------------------------------------------------------
259 // Thread class
260 //------------------------------------------------------------------
261 
262 ConstString &
263 Thread::GetStaticBroadcasterClass ()
264 {
265     static ConstString class_name ("lldb.thread");
266     return class_name;
267 }
268 
269 Thread::Thread (Process &process, lldb::tid_t tid, bool use_invalid_index_id) :
270     ThreadProperties (false),
271     UserID (tid),
272     Broadcaster(&process.GetTarget().GetDebugger(), Thread::GetStaticBroadcasterClass().AsCString()),
273     m_process_wp (process.shared_from_this()),
274     m_stop_info_sp (),
275     m_stop_info_stop_id (0),
276     m_stop_info_override_stop_id (0),
277     m_index_id (use_invalid_index_id ? LLDB_INVALID_INDEX32 : process.GetNextThreadIndexID(tid)),
278     m_reg_context_sp (),
279     m_state (eStateUnloaded),
280     m_state_mutex (Mutex::eMutexTypeRecursive),
281     m_plan_stack (),
282     m_completed_plan_stack(),
283     m_frame_mutex (Mutex::eMutexTypeRecursive),
284     m_curr_frames_sp (),
285     m_prev_frames_sp (),
286     m_resume_signal (LLDB_INVALID_SIGNAL_NUMBER),
287     m_resume_state (eStateRunning),
288     m_temporary_resume_state (eStateRunning),
289     m_unwinder_ap (),
290     m_destroy_called (false),
291     m_override_should_notify (eLazyBoolCalculate),
292     m_extended_info_fetched (false),
293     m_extended_info ()
294 {
295     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_OBJECT));
296     if (log)
297         log->Printf ("%p Thread::Thread(tid = 0x%4.4" PRIx64 ")",
298                      static_cast<void*>(this), GetID());
299 
300     CheckInWithManager();
301     QueueFundamentalPlan(true);
302 }
303 
304 Thread::~Thread()
305 {
306     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_OBJECT));
307     if (log)
308         log->Printf ("%p Thread::~Thread(tid = 0x%4.4" PRIx64 ")",
309                      static_cast<void*>(this), GetID());
310     /// If you hit this assert, it means your derived class forgot to call DoDestroy in its destructor.
311     assert (m_destroy_called);
312 }
313 
314 void
315 Thread::DestroyThread ()
316 {
317     // Tell any plans on the plan stacks that the thread is being destroyed since
318     // any plans that have a thread go away in the middle of might need
319     // to do cleanup, or in some cases NOT do cleanup...
320     for (auto plan : m_plan_stack)
321         plan->ThreadDestroyed();
322 
323     for (auto plan : m_discarded_plan_stack)
324         plan->ThreadDestroyed();
325 
326     for (auto plan : m_completed_plan_stack)
327         plan->ThreadDestroyed();
328 
329     m_destroy_called = true;
330     m_plan_stack.clear();
331     m_discarded_plan_stack.clear();
332     m_completed_plan_stack.clear();
333 
334     // Push a ThreadPlanNull on the plan stack.  That way we can continue assuming that the
335     // plan stack is never empty, but if somebody errantly asks questions of a destroyed thread
336     // without checking first whether it is destroyed, they won't crash.
337     ThreadPlanSP null_plan_sp(new ThreadPlanNull (*this));
338     m_plan_stack.push_back (null_plan_sp);
339 
340     m_stop_info_sp.reset();
341     m_reg_context_sp.reset();
342     m_unwinder_ap.reset();
343     Mutex::Locker locker(m_frame_mutex);
344     m_curr_frames_sp.reset();
345     m_prev_frames_sp.reset();
346 }
347 
348 void
349 Thread::BroadcastSelectedFrameChange(StackID &new_frame_id)
350 {
351     if (EventTypeHasListeners(eBroadcastBitSelectedFrameChanged))
352         BroadcastEvent(eBroadcastBitSelectedFrameChanged, new ThreadEventData (this->shared_from_this(), new_frame_id));
353 }
354 
355 lldb::StackFrameSP
356 Thread::GetSelectedFrame()
357 {
358     StackFrameListSP stack_frame_list_sp(GetStackFrameList());
359     StackFrameSP frame_sp = stack_frame_list_sp->GetFrameAtIndex (stack_frame_list_sp->GetSelectedFrameIndex());
360     FunctionOptimizationWarning (frame_sp.get());
361     return frame_sp;
362 }
363 
364 uint32_t
365 Thread::SetSelectedFrame (lldb_private::StackFrame *frame, bool broadcast)
366 {
367     uint32_t ret_value = GetStackFrameList()->SetSelectedFrame(frame);
368     if (broadcast)
369         BroadcastSelectedFrameChange(frame->GetStackID());
370     FunctionOptimizationWarning (frame);
371     return ret_value;
372 }
373 
374 bool
375 Thread::SetSelectedFrameByIndex (uint32_t frame_idx, bool broadcast)
376 {
377     StackFrameSP frame_sp(GetStackFrameList()->GetFrameAtIndex (frame_idx));
378     if (frame_sp)
379     {
380         GetStackFrameList()->SetSelectedFrame(frame_sp.get());
381         if (broadcast)
382             BroadcastSelectedFrameChange(frame_sp->GetStackID());
383         FunctionOptimizationWarning (frame_sp.get());
384         return true;
385     }
386     else
387         return false;
388 }
389 
390 bool
391 Thread::SetSelectedFrameByIndexNoisily (uint32_t frame_idx, Stream &output_stream)
392 {
393     const bool broadcast = true;
394     bool success = SetSelectedFrameByIndex (frame_idx, broadcast);
395     if (success)
396     {
397         StackFrameSP frame_sp = GetSelectedFrame();
398         if (frame_sp)
399         {
400             bool already_shown = false;
401             SymbolContext frame_sc(frame_sp->GetSymbolContext(eSymbolContextLineEntry));
402             if (GetProcess()->GetTarget().GetDebugger().GetUseExternalEditor() && frame_sc.line_entry.file && frame_sc.line_entry.line != 0)
403             {
404                 already_shown = Host::OpenFileInExternalEditor (frame_sc.line_entry.file, frame_sc.line_entry.line);
405             }
406 
407             bool show_frame_info = true;
408             bool show_source = !already_shown;
409             FunctionOptimizationWarning (frame_sp.get());
410             return frame_sp->GetStatus (output_stream, show_frame_info, show_source);
411         }
412         return false;
413     }
414     else
415         return false;
416 }
417 
418 void
419 Thread::FunctionOptimizationWarning (StackFrame *frame)
420 {
421     if (frame && frame->HasDebugInformation() && GetProcess()->GetWarningsOptimization())
422     {
423         SymbolContext sc = frame->GetSymbolContext (eSymbolContextFunction | eSymbolContextModule);
424         GetProcess()->PrintWarningOptimization (sc);
425     }
426 }
427 
428 lldb::StopInfoSP
429 Thread::GetStopInfo ()
430 {
431     if (m_destroy_called)
432         return m_stop_info_sp;
433 
434     ThreadPlanSP plan_sp (GetCompletedPlan());
435     ProcessSP process_sp (GetProcess());
436     const uint32_t stop_id = process_sp ? process_sp->GetStopID() : UINT32_MAX;
437     if (plan_sp && plan_sp->PlanSucceeded())
438     {
439         return StopInfo::CreateStopReasonWithPlan (plan_sp, GetReturnValueObject(), GetExpressionVariable());
440     }
441     else
442     {
443         if ((m_stop_info_stop_id == stop_id) ||   // Stop info is valid, just return what we have (even if empty)
444             (m_stop_info_sp && m_stop_info_sp->IsValid()))  // Stop info is valid, just return what we have
445         {
446             return m_stop_info_sp;
447         }
448         else
449         {
450             GetPrivateStopInfo ();
451             return m_stop_info_sp;
452         }
453     }
454 }
455 
456 lldb::StopInfoSP
457 Thread::GetPrivateStopInfo ()
458 {
459     if (m_destroy_called)
460         return m_stop_info_sp;
461 
462     ProcessSP process_sp (GetProcess());
463     if (process_sp)
464     {
465         const uint32_t process_stop_id = process_sp->GetStopID();
466         if (m_stop_info_stop_id != process_stop_id)
467         {
468             if (m_stop_info_sp)
469             {
470                 if (m_stop_info_sp->IsValid()
471                     || IsStillAtLastBreakpointHit()
472                     || GetCurrentPlan()->IsVirtualStep())
473                     SetStopInfo (m_stop_info_sp);
474                 else
475                     m_stop_info_sp.reset();
476             }
477 
478             if (!m_stop_info_sp)
479             {
480                 if (!CalculateStopInfo())
481                     SetStopInfo (StopInfoSP());
482             }
483         }
484 
485         // The stop info can be manually set by calling Thread::SetStopInfo()
486         // prior to this function ever getting called, so we can't rely on
487         // "m_stop_info_stop_id != process_stop_id" as the condition for
488         // the if statement below, we must also check the stop info to see
489         // if we need to override it. See the header documentation in
490         // Process::GetStopInfoOverrideCallback() for more information on
491         // the stop info override callback.
492         if (m_stop_info_override_stop_id != process_stop_id)
493         {
494             m_stop_info_override_stop_id = process_stop_id;
495             if (m_stop_info_sp)
496             {
497                 ArchSpec::StopInfoOverrideCallbackType callback = GetProcess()->GetStopInfoOverrideCallback();
498                 if (callback)
499                     callback(*this);
500             }
501         }
502     }
503     return m_stop_info_sp;
504 }
505 
506 lldb::StopReason
507 Thread::GetStopReason()
508 {
509     lldb::StopInfoSP stop_info_sp (GetStopInfo ());
510     if (stop_info_sp)
511         return stop_info_sp->GetStopReason();
512     return eStopReasonNone;
513 }
514 
515 bool
516 Thread::StopInfoIsUpToDate() const
517 {
518     ProcessSP process_sp (GetProcess());
519     if (process_sp)
520         return m_stop_info_stop_id == process_sp->GetStopID();
521     else
522         return true; // Process is no longer around so stop info is always up to date...
523 }
524 
525 void
526 Thread::SetStopInfo (const lldb::StopInfoSP &stop_info_sp)
527 {
528     m_stop_info_sp = stop_info_sp;
529     if (m_stop_info_sp)
530     {
531         m_stop_info_sp->MakeStopInfoValid();
532         // If we are overriding the ShouldReportStop, do that here:
533         if (m_override_should_notify != eLazyBoolCalculate)
534             m_stop_info_sp->OverrideShouldNotify (m_override_should_notify == eLazyBoolYes);
535     }
536 
537     ProcessSP process_sp (GetProcess());
538     if (process_sp)
539         m_stop_info_stop_id = process_sp->GetStopID();
540     else
541         m_stop_info_stop_id = UINT32_MAX;
542     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_THREAD));
543     if (log)
544         log->Printf("%p: tid = 0x%" PRIx64 ": stop info = %s (stop_id = %u)",
545                     static_cast<void*>(this), GetID(),
546                     stop_info_sp ? stop_info_sp->GetDescription() : "<NULL>",
547                     m_stop_info_stop_id);
548 }
549 
550 void
551 Thread::SetShouldReportStop (Vote vote)
552 {
553     if (vote == eVoteNoOpinion)
554         return;
555     else
556     {
557         m_override_should_notify = (vote == eVoteYes ? eLazyBoolYes : eLazyBoolNo);
558         if (m_stop_info_sp)
559             m_stop_info_sp->OverrideShouldNotify (m_override_should_notify == eLazyBoolYes);
560     }
561 }
562 
563 void
564 Thread::SetStopInfoToNothing()
565 {
566     // Note, we can't just NULL out the private reason, or the native thread implementation will try to
567     // go calculate it again.  For now, just set it to a Unix Signal with an invalid signal number.
568     SetStopInfo (StopInfo::CreateStopReasonWithSignal (*this,  LLDB_INVALID_SIGNAL_NUMBER));
569 }
570 
571 bool
572 Thread::ThreadStoppedForAReason (void)
573 {
574     return (bool) GetPrivateStopInfo ();
575 }
576 
577 bool
578 Thread::CheckpointThreadState (ThreadStateCheckpoint &saved_state)
579 {
580     saved_state.register_backup_sp.reset();
581     lldb::StackFrameSP frame_sp(GetStackFrameAtIndex (0));
582     if (frame_sp)
583     {
584         lldb::RegisterCheckpointSP reg_checkpoint_sp(new RegisterCheckpoint(RegisterCheckpoint::Reason::eExpression));
585         if (reg_checkpoint_sp)
586         {
587             lldb::RegisterContextSP reg_ctx_sp (frame_sp->GetRegisterContext());
588             if (reg_ctx_sp && reg_ctx_sp->ReadAllRegisterValues (*reg_checkpoint_sp))
589                 saved_state.register_backup_sp = reg_checkpoint_sp;
590         }
591     }
592     if (!saved_state.register_backup_sp)
593         return false;
594 
595     saved_state.stop_info_sp = GetStopInfo();
596     ProcessSP process_sp (GetProcess());
597     if (process_sp)
598         saved_state.orig_stop_id = process_sp->GetStopID();
599     saved_state.current_inlined_depth = GetCurrentInlinedDepth();
600 
601     return true;
602 }
603 
604 bool
605 Thread::RestoreRegisterStateFromCheckpoint (ThreadStateCheckpoint &saved_state)
606 {
607     if (saved_state.register_backup_sp)
608     {
609         lldb::StackFrameSP frame_sp(GetStackFrameAtIndex (0));
610         if (frame_sp)
611         {
612             lldb::RegisterContextSP reg_ctx_sp (frame_sp->GetRegisterContext());
613             if (reg_ctx_sp)
614             {
615                 bool ret = reg_ctx_sp->WriteAllRegisterValues (*saved_state.register_backup_sp);
616 
617                 // Clear out all stack frames as our world just changed.
618                 ClearStackFrames();
619                 reg_ctx_sp->InvalidateIfNeeded(true);
620                 if (m_unwinder_ap.get())
621                     m_unwinder_ap->Clear();
622                 return ret;
623             }
624         }
625     }
626     return false;
627 }
628 
629 bool
630 Thread::RestoreThreadStateFromCheckpoint (ThreadStateCheckpoint &saved_state)
631 {
632     if (saved_state.stop_info_sp)
633         saved_state.stop_info_sp->MakeStopInfoValid();
634     SetStopInfo(saved_state.stop_info_sp);
635     GetStackFrameList()->SetCurrentInlinedDepth (saved_state.current_inlined_depth);
636     return true;
637 }
638 
639 StateType
640 Thread::GetState() const
641 {
642     // If any other threads access this we will need a mutex for it
643     Mutex::Locker locker(m_state_mutex);
644     return m_state;
645 }
646 
647 void
648 Thread::SetState(StateType state)
649 {
650     Mutex::Locker locker(m_state_mutex);
651     m_state = state;
652 }
653 
654 void
655 Thread::WillStop()
656 {
657     ThreadPlan *current_plan = GetCurrentPlan();
658 
659     // FIXME: I may decide to disallow threads with no plans.  In which
660     // case this should go to an assert.
661 
662     if (!current_plan)
663         return;
664 
665     current_plan->WillStop();
666 }
667 
668 void
669 Thread::SetupForResume ()
670 {
671     if (GetResumeState() != eStateSuspended)
672     {
673         // If we're at a breakpoint push the step-over breakpoint plan.  Do this before
674         // telling the current plan it will resume, since we might change what the current
675         // plan is.
676 
677         lldb::RegisterContextSP reg_ctx_sp (GetRegisterContext());
678         if (reg_ctx_sp)
679         {
680             const addr_t thread_pc = reg_ctx_sp->GetPC();
681             BreakpointSiteSP bp_site_sp = GetProcess()->GetBreakpointSiteList().FindByAddress(thread_pc);
682             if (bp_site_sp)
683             {
684                 // Note, don't assume there's a ThreadPlanStepOverBreakpoint, the target may not require anything
685                 // special to step over a breakpoint.
686 
687                 ThreadPlan *cur_plan = GetCurrentPlan();
688 
689                 bool push_step_over_bp_plan = false;
690                 if (cur_plan->GetKind() == ThreadPlan::eKindStepOverBreakpoint)
691                 {
692                     ThreadPlanStepOverBreakpoint *bp_plan = (ThreadPlanStepOverBreakpoint *)cur_plan;
693                     if (bp_plan->GetBreakpointLoadAddress() != thread_pc)
694                         push_step_over_bp_plan = true;
695                 }
696                 else
697                     push_step_over_bp_plan = true;
698 
699                 if (push_step_over_bp_plan)
700                 {
701                     ThreadPlanSP step_bp_plan_sp (new ThreadPlanStepOverBreakpoint (*this));
702                     if (step_bp_plan_sp)
703                     {
704                         step_bp_plan_sp->SetPrivate (true);
705 
706                         if (GetCurrentPlan()->RunState() != eStateStepping)
707                         {
708                             ThreadPlanStepOverBreakpoint *step_bp_plan
709                                     = static_cast<ThreadPlanStepOverBreakpoint *>(step_bp_plan_sp.get());
710                             step_bp_plan->SetAutoContinue(true);
711                         }
712                         QueueThreadPlan (step_bp_plan_sp, false);
713                     }
714                 }
715             }
716         }
717     }
718 }
719 
720 bool
721 Thread::ShouldResume (StateType resume_state)
722 {
723     // At this point clear the completed plan stack.
724     m_completed_plan_stack.clear();
725     m_discarded_plan_stack.clear();
726     m_override_should_notify = eLazyBoolCalculate;
727 
728     StateType prev_resume_state = GetTemporaryResumeState();
729 
730     SetTemporaryResumeState(resume_state);
731 
732     lldb::ThreadSP backing_thread_sp (GetBackingThread ());
733     if (backing_thread_sp)
734         backing_thread_sp->SetTemporaryResumeState(resume_state);
735 
736     // Make sure m_stop_info_sp is valid.  Don't do this for threads we suspended in the previous run.
737     if (prev_resume_state != eStateSuspended)
738         GetPrivateStopInfo();
739 
740     // This is a little dubious, but we are trying to limit how often we actually fetch stop info from
741     // the target, 'cause that slows down single stepping.  So assume that if we got to the point where
742     // we're about to resume, and we haven't yet had to fetch the stop reason, then it doesn't need to know
743     // about the fact that we are resuming...
744     const uint32_t process_stop_id = GetProcess()->GetStopID();
745     if (m_stop_info_stop_id == process_stop_id &&
746         (m_stop_info_sp && m_stop_info_sp->IsValid()))
747     {
748         StopInfo *stop_info = GetPrivateStopInfo().get();
749         if (stop_info)
750             stop_info->WillResume (resume_state);
751     }
752 
753     // Tell all the plans that we are about to resume in case they need to clear any state.
754     // We distinguish between the plan on the top of the stack and the lower
755     // plans in case a plan needs to do any special business before it runs.
756 
757     bool need_to_resume = false;
758     ThreadPlan *plan_ptr = GetCurrentPlan();
759     if (plan_ptr)
760     {
761         need_to_resume = plan_ptr->WillResume(resume_state, true);
762 
763         while ((plan_ptr = GetPreviousPlan(plan_ptr)) != nullptr)
764         {
765             plan_ptr->WillResume (resume_state, false);
766         }
767 
768         // If the WillResume for the plan says we are faking a resume, then it will have set an appropriate stop info.
769         // In that case, don't reset it here.
770 
771         if (need_to_resume && resume_state != eStateSuspended)
772         {
773             m_stop_info_sp.reset();
774         }
775     }
776 
777     if (need_to_resume)
778     {
779         ClearStackFrames();
780         // Let Thread subclasses do any special work they need to prior to resuming
781         WillResume (resume_state);
782     }
783 
784     return need_to_resume;
785 }
786 
787 void
788 Thread::DidResume ()
789 {
790     SetResumeSignal (LLDB_INVALID_SIGNAL_NUMBER);
791 }
792 
793 void
794 Thread::DidStop ()
795 {
796     SetState (eStateStopped);
797 }
798 
799 bool
800 Thread::ShouldStop (Event* event_ptr)
801 {
802     ThreadPlan *current_plan = GetCurrentPlan();
803 
804     bool should_stop = true;
805 
806     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
807 
808     if (GetResumeState () == eStateSuspended)
809     {
810         if (log)
811             log->Printf ("Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64 ", should_stop = 0 (ignore since thread was suspended)",
812                          __FUNCTION__, GetID (), GetProtocolID());
813         return false;
814     }
815 
816     if (GetTemporaryResumeState () == eStateSuspended)
817     {
818         if (log)
819             log->Printf ("Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64 ", should_stop = 0 (ignore since thread was suspended)",
820                          __FUNCTION__, GetID (), GetProtocolID());
821         return false;
822     }
823 
824     // Based on the current thread plan and process stop info, check if this
825     // thread caused the process to stop. NOTE: this must take place before
826     // the plan is moved from the current plan stack to the completed plan
827     // stack.
828     if (!ThreadStoppedForAReason())
829     {
830         if (log)
831             log->Printf ("Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64 ", pc = 0x%16.16" PRIx64 ", should_stop = 0 (ignore since no stop reason)",
832                          __FUNCTION__, GetID (), GetProtocolID(),
833                          GetRegisterContext() ? GetRegisterContext()->GetPC() : LLDB_INVALID_ADDRESS);
834         return false;
835     }
836 
837     if (log)
838     {
839         log->Printf ("Thread::%s(%p) for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64 ", pc = 0x%16.16" PRIx64,
840                      __FUNCTION__, static_cast<void*>(this), GetID (),
841                      GetProtocolID (),
842                      GetRegisterContext()
843                         ? GetRegisterContext()->GetPC()
844                         : LLDB_INVALID_ADDRESS);
845         log->Printf ("^^^^^^^^ Thread::ShouldStop Begin ^^^^^^^^");
846         StreamString s;
847         s.IndentMore();
848         DumpThreadPlans(&s);
849         log->Printf ("Plan stack initial state:\n%s", s.GetData());
850     }
851 
852     // The top most plan always gets to do the trace log...
853     current_plan->DoTraceLog ();
854 
855     // First query the stop info's ShouldStopSynchronous.  This handles "synchronous" stop reasons, for example the breakpoint
856     // command on internal breakpoints.  If a synchronous stop reason says we should not stop, then we don't have to
857     // do any more work on this stop.
858     StopInfoSP private_stop_info (GetPrivateStopInfo());
859     if (private_stop_info && !private_stop_info->ShouldStopSynchronous(event_ptr))
860     {
861         if (log)
862             log->Printf ("StopInfo::ShouldStop async callback says we should not stop, returning ShouldStop of false.");
863         return false;
864     }
865 
866     // If we've already been restarted, don't query the plans since the state they would examine is not current.
867     if (Process::ProcessEventData::GetRestartedFromEvent(event_ptr))
868         return false;
869 
870     // Before the plans see the state of the world, calculate the current inlined depth.
871     GetStackFrameList()->CalculateCurrentInlinedDepth();
872 
873     // If the base plan doesn't understand why we stopped, then we have to find a plan that does.
874     // If that plan is still working, then we don't need to do any more work.  If the plan that explains
875     // the stop is done, then we should pop all the plans below it, and pop it, and then let the plans above it decide
876     // whether they still need to do more work.
877 
878     bool done_processing_current_plan = false;
879 
880     if (!current_plan->PlanExplainsStop(event_ptr))
881     {
882         if (current_plan->TracerExplainsStop())
883         {
884             done_processing_current_plan = true;
885             should_stop = false;
886         }
887         else
888         {
889             // If the current plan doesn't explain the stop, then find one that
890             // does and let it handle the situation.
891             ThreadPlan *plan_ptr = current_plan;
892             while ((plan_ptr = GetPreviousPlan(plan_ptr)) != nullptr)
893             {
894                 if (plan_ptr->PlanExplainsStop(event_ptr))
895                 {
896                     should_stop = plan_ptr->ShouldStop (event_ptr);
897 
898                     // plan_ptr explains the stop, next check whether plan_ptr is done, if so, then we should take it
899                     // and all the plans below it off the stack.
900 
901                     if (plan_ptr->MischiefManaged())
902                     {
903                         // We're going to pop the plans up to and including the plan that explains the stop.
904                         ThreadPlan *prev_plan_ptr = GetPreviousPlan (plan_ptr);
905 
906                         do
907                         {
908                             if (should_stop)
909                                 current_plan->WillStop();
910                             PopPlan();
911                         }
912                         while ((current_plan = GetCurrentPlan()) != prev_plan_ptr);
913                         // Now, if the responsible plan was not "Okay to discard" then we're done,
914                         // otherwise we forward this to the next plan in the stack below.
915                         done_processing_current_plan = (plan_ptr->IsMasterPlan() && !plan_ptr->OkayToDiscard());
916                     }
917                     else
918                         done_processing_current_plan = true;
919 
920                     break;
921                 }
922             }
923         }
924     }
925 
926     if (!done_processing_current_plan)
927     {
928         bool over_ride_stop = current_plan->ShouldAutoContinue(event_ptr);
929 
930         if (log)
931             log->Printf("Plan %s explains stop, auto-continue %i.",
932                         current_plan->GetName(), over_ride_stop);
933 
934         // We're starting from the base plan, so just let it decide;
935         if (PlanIsBasePlan(current_plan))
936         {
937             should_stop = current_plan->ShouldStop (event_ptr);
938             if (log)
939                 log->Printf("Base plan says should stop: %i.", should_stop);
940         }
941         else
942         {
943             // Otherwise, don't let the base plan override what the other plans say to do, since
944             // presumably if there were other plans they would know what to do...
945             while (1)
946             {
947                 if (PlanIsBasePlan(current_plan))
948                     break;
949 
950                 should_stop = current_plan->ShouldStop(event_ptr);
951                 if (log)
952                     log->Printf("Plan %s should stop: %d.",
953                                 current_plan->GetName(), should_stop);
954                 if (current_plan->MischiefManaged())
955                 {
956                     if (should_stop)
957                         current_plan->WillStop();
958 
959                     // If a Master Plan wants to stop, and wants to stick on the stack, we let it.
960                     // Otherwise, see if the plan's parent wants to stop.
961 
962                     if (should_stop && current_plan->IsMasterPlan() && !current_plan->OkayToDiscard())
963                     {
964                         PopPlan();
965                         break;
966                     }
967                     else
968                     {
969                         PopPlan();
970 
971                         current_plan = GetCurrentPlan();
972                         if (current_plan == nullptr)
973                         {
974                             break;
975                         }
976                     }
977                 }
978                 else
979                 {
980                     break;
981                 }
982             }
983         }
984 
985         if (over_ride_stop)
986             should_stop = false;
987     }
988 
989     // One other potential problem is that we set up a master plan, then stop in before it is complete - for instance
990     // by hitting a breakpoint during a step-over - then do some step/finish/etc operations that wind up
991     // past the end point condition of the initial plan.  We don't want to strand the original plan on the stack,
992     // This code clears stale plans off the stack.
993 
994     if (should_stop)
995     {
996         ThreadPlan *plan_ptr = GetCurrentPlan();
997         while (!PlanIsBasePlan(plan_ptr))
998         {
999             bool stale = plan_ptr->IsPlanStale ();
1000             ThreadPlan *examined_plan = plan_ptr;
1001             plan_ptr = GetPreviousPlan (examined_plan);
1002 
1003             if (stale)
1004             {
1005                 if (log)
1006                     log->Printf("Plan %s being discarded in cleanup, it says it is already done.",
1007                                 examined_plan->GetName());
1008                 DiscardThreadPlansUpToPlan(examined_plan);
1009             }
1010         }
1011     }
1012 
1013     if (log)
1014     {
1015         StreamString s;
1016         s.IndentMore();
1017         DumpThreadPlans(&s);
1018         log->Printf ("Plan stack final state:\n%s", s.GetData());
1019         log->Printf ("vvvvvvvv Thread::ShouldStop End (returning %i) vvvvvvvv", should_stop);
1020     }
1021     return should_stop;
1022 }
1023 
1024 Vote
1025 Thread::ShouldReportStop (Event* event_ptr)
1026 {
1027     StateType thread_state = GetResumeState ();
1028     StateType temp_thread_state = GetTemporaryResumeState();
1029 
1030     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1031 
1032     if (thread_state == eStateSuspended || thread_state == eStateInvalid)
1033     {
1034         if (log)
1035             log->Printf ("Thread::ShouldReportStop() tid = 0x%4.4" PRIx64 ": returning vote %i (state was suspended or invalid)", GetID(), eVoteNoOpinion);
1036         return eVoteNoOpinion;
1037     }
1038 
1039     if (temp_thread_state == eStateSuspended || temp_thread_state == eStateInvalid)
1040     {
1041         if (log)
1042             log->Printf ("Thread::ShouldReportStop() tid = 0x%4.4" PRIx64 ": returning vote %i (temporary state was suspended or invalid)", GetID(), eVoteNoOpinion);
1043         return eVoteNoOpinion;
1044     }
1045 
1046     if (!ThreadStoppedForAReason())
1047     {
1048         if (log)
1049             log->Printf ("Thread::ShouldReportStop() tid = 0x%4.4" PRIx64 ": returning vote %i (thread didn't stop for a reason.)", GetID(), eVoteNoOpinion);
1050         return eVoteNoOpinion;
1051     }
1052 
1053     if (m_completed_plan_stack.size() > 0)
1054     {
1055         // Don't use GetCompletedPlan here, since that suppresses private plans.
1056         if (log)
1057             log->Printf ("Thread::ShouldReportStop() tid = 0x%4.4" PRIx64 ": returning vote  for complete stack's back plan", GetID());
1058         return m_completed_plan_stack.back()->ShouldReportStop (event_ptr);
1059     }
1060     else
1061     {
1062         Vote thread_vote = eVoteNoOpinion;
1063         ThreadPlan *plan_ptr = GetCurrentPlan();
1064         while (1)
1065         {
1066             if (plan_ptr->PlanExplainsStop(event_ptr))
1067             {
1068                 thread_vote = plan_ptr->ShouldReportStop(event_ptr);
1069                 break;
1070             }
1071             if (PlanIsBasePlan(plan_ptr))
1072                 break;
1073             else
1074                 plan_ptr = GetPreviousPlan(plan_ptr);
1075         }
1076         if (log)
1077             log->Printf ("Thread::ShouldReportStop() tid = 0x%4.4" PRIx64 ": returning vote %i for current plan", GetID(), thread_vote);
1078 
1079         return thread_vote;
1080     }
1081 }
1082 
1083 Vote
1084 Thread::ShouldReportRun (Event* event_ptr)
1085 {
1086     StateType thread_state = GetResumeState ();
1087 
1088     if (thread_state == eStateSuspended
1089             || thread_state == eStateInvalid)
1090     {
1091         return eVoteNoOpinion;
1092     }
1093 
1094     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1095     if (m_completed_plan_stack.size() > 0)
1096     {
1097         // Don't use GetCompletedPlan here, since that suppresses private plans.
1098         if (log)
1099             log->Printf ("Current Plan for thread %d(%p) (0x%4.4" PRIx64 ", %s): %s being asked whether we should report run.",
1100                          GetIndexID(), static_cast<void*>(this), GetID(),
1101                          StateAsCString(GetTemporaryResumeState()),
1102                          m_completed_plan_stack.back()->GetName());
1103 
1104         return m_completed_plan_stack.back()->ShouldReportRun (event_ptr);
1105     }
1106     else
1107     {
1108         if (log)
1109             log->Printf ("Current Plan for thread %d(%p) (0x%4.4" PRIx64 ", %s): %s being asked whether we should report run.",
1110                          GetIndexID(), static_cast<void*>(this), GetID(),
1111                          StateAsCString(GetTemporaryResumeState()),
1112                          GetCurrentPlan()->GetName());
1113 
1114         return GetCurrentPlan()->ShouldReportRun (event_ptr);
1115      }
1116 }
1117 
1118 bool
1119 Thread::MatchesSpec (const ThreadSpec *spec)
1120 {
1121     return (spec == nullptr) ? true : spec->ThreadPassesBasicTests(*this);
1122 }
1123 
1124 void
1125 Thread::PushPlan (ThreadPlanSP &thread_plan_sp)
1126 {
1127     if (thread_plan_sp)
1128     {
1129         // If the thread plan doesn't already have a tracer, give it its parent's tracer:
1130         if (!thread_plan_sp->GetThreadPlanTracer())
1131             thread_plan_sp->SetThreadPlanTracer(m_plan_stack.back()->GetThreadPlanTracer());
1132         m_plan_stack.push_back (thread_plan_sp);
1133 
1134         thread_plan_sp->DidPush();
1135 
1136         Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1137         if (log)
1138         {
1139             StreamString s;
1140             thread_plan_sp->GetDescription (&s, lldb::eDescriptionLevelFull);
1141             log->Printf("Thread::PushPlan(0x%p): \"%s\", tid = 0x%4.4" PRIx64 ".",
1142                         static_cast<void*>(this), s.GetData(),
1143                         thread_plan_sp->GetThread().GetID());
1144         }
1145     }
1146 }
1147 
1148 void
1149 Thread::PopPlan ()
1150 {
1151     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1152 
1153     if (m_plan_stack.size() <= 1)
1154         return;
1155     else
1156     {
1157         ThreadPlanSP &plan = m_plan_stack.back();
1158         if (log)
1159         {
1160             log->Printf("Popping plan: \"%s\", tid = 0x%4.4" PRIx64 ".", plan->GetName(), plan->GetThread().GetID());
1161         }
1162         m_completed_plan_stack.push_back (plan);
1163         plan->WillPop();
1164         m_plan_stack.pop_back();
1165     }
1166 }
1167 
1168 void
1169 Thread::DiscardPlan ()
1170 {
1171     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1172     if (m_plan_stack.size() > 1)
1173     {
1174         ThreadPlanSP &plan = m_plan_stack.back();
1175         if (log)
1176             log->Printf("Discarding plan: \"%s\", tid = 0x%4.4" PRIx64 ".", plan->GetName(), plan->GetThread().GetID());
1177 
1178         m_discarded_plan_stack.push_back (plan);
1179         plan->WillPop();
1180         m_plan_stack.pop_back();
1181     }
1182 }
1183 
1184 ThreadPlan *
1185 Thread::GetCurrentPlan ()
1186 {
1187     // There will always be at least the base plan.  If somebody is mucking with a
1188     // thread with an empty plan stack, we should assert right away.
1189     return m_plan_stack.empty() ? nullptr : m_plan_stack.back().get();
1190 }
1191 
1192 ThreadPlanSP
1193 Thread::GetCompletedPlan ()
1194 {
1195     ThreadPlanSP empty_plan_sp;
1196     if (!m_completed_plan_stack.empty())
1197     {
1198         for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--)
1199         {
1200             ThreadPlanSP completed_plan_sp;
1201             completed_plan_sp = m_completed_plan_stack[i];
1202             if (!completed_plan_sp->GetPrivate ())
1203             return completed_plan_sp;
1204         }
1205     }
1206     return empty_plan_sp;
1207 }
1208 
1209 ValueObjectSP
1210 Thread::GetReturnValueObject ()
1211 {
1212     if (!m_completed_plan_stack.empty())
1213     {
1214         for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--)
1215         {
1216             ValueObjectSP return_valobj_sp;
1217             return_valobj_sp = m_completed_plan_stack[i]->GetReturnValueObject();
1218             if (return_valobj_sp)
1219                 return return_valobj_sp;
1220         }
1221     }
1222     return ValueObjectSP();
1223 }
1224 
1225 ExpressionVariableSP
1226 Thread::GetExpressionVariable ()
1227 {
1228     if (!m_completed_plan_stack.empty())
1229     {
1230         for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--)
1231         {
1232             ExpressionVariableSP expression_variable_sp;
1233             expression_variable_sp = m_completed_plan_stack[i]->GetExpressionVariable();
1234             if (expression_variable_sp)
1235                 return expression_variable_sp;
1236         }
1237     }
1238     return ExpressionVariableSP();
1239 }
1240 
1241 bool
1242 Thread::IsThreadPlanDone (ThreadPlan *plan)
1243 {
1244     if (!m_completed_plan_stack.empty())
1245     {
1246         for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--)
1247         {
1248             if (m_completed_plan_stack[i].get() == plan)
1249                 return true;
1250         }
1251     }
1252     return false;
1253 }
1254 
1255 bool
1256 Thread::WasThreadPlanDiscarded (ThreadPlan *plan)
1257 {
1258     if (!m_discarded_plan_stack.empty())
1259     {
1260         for (int i = m_discarded_plan_stack.size() - 1; i >= 0; i--)
1261         {
1262             if (m_discarded_plan_stack[i].get() == plan)
1263                 return true;
1264         }
1265     }
1266     return false;
1267 }
1268 
1269 ThreadPlan *
1270 Thread::GetPreviousPlan (ThreadPlan *current_plan)
1271 {
1272     if (current_plan == nullptr)
1273         return nullptr;
1274 
1275     int stack_size = m_completed_plan_stack.size();
1276     for (int i = stack_size - 1; i > 0; i--)
1277     {
1278         if (current_plan == m_completed_plan_stack[i].get())
1279             return m_completed_plan_stack[i-1].get();
1280     }
1281 
1282     if (stack_size > 0 && m_completed_plan_stack[0].get() == current_plan)
1283     {
1284         return GetCurrentPlan();
1285     }
1286 
1287     stack_size = m_plan_stack.size();
1288     for (int i = stack_size - 1; i > 0; i--)
1289     {
1290         if (current_plan == m_plan_stack[i].get())
1291             return m_plan_stack[i-1].get();
1292     }
1293     return nullptr;
1294 }
1295 
1296 void
1297 Thread::QueueThreadPlan (ThreadPlanSP &thread_plan_sp, bool abort_other_plans)
1298 {
1299     if (abort_other_plans)
1300        DiscardThreadPlans(true);
1301 
1302     PushPlan (thread_plan_sp);
1303 }
1304 
1305 void
1306 Thread::EnableTracer (bool value, bool single_stepping)
1307 {
1308     int stack_size = m_plan_stack.size();
1309     for (int i = 0; i < stack_size; i++)
1310     {
1311         if (m_plan_stack[i]->GetThreadPlanTracer())
1312         {
1313             m_plan_stack[i]->GetThreadPlanTracer()->EnableTracing(value);
1314             m_plan_stack[i]->GetThreadPlanTracer()->EnableSingleStep(single_stepping);
1315         }
1316     }
1317 }
1318 
1319 void
1320 Thread::SetTracer (lldb::ThreadPlanTracerSP &tracer_sp)
1321 {
1322     int stack_size = m_plan_stack.size();
1323     for (int i = 0; i < stack_size; i++)
1324         m_plan_stack[i]->SetThreadPlanTracer(tracer_sp);
1325 }
1326 
1327 bool
1328 Thread::DiscardUserThreadPlansUpToIndex (uint32_t thread_index)
1329 {
1330     // Count the user thread plans from the back end to get the number of the one we want
1331     // to discard:
1332 
1333     uint32_t idx = 0;
1334     ThreadPlan *up_to_plan_ptr = nullptr;
1335 
1336     for (ThreadPlanSP plan_sp : m_plan_stack)
1337     {
1338         if (plan_sp->GetPrivate())
1339             continue;
1340         if (idx == thread_index)
1341         {
1342             up_to_plan_ptr = plan_sp.get();
1343             break;
1344         }
1345         else
1346             idx++;
1347     }
1348 
1349     if (up_to_plan_ptr == nullptr)
1350         return false;
1351 
1352     DiscardThreadPlansUpToPlan(up_to_plan_ptr);
1353     return true;
1354 }
1355 
1356 void
1357 Thread::DiscardThreadPlansUpToPlan (lldb::ThreadPlanSP &up_to_plan_sp)
1358 {
1359     DiscardThreadPlansUpToPlan (up_to_plan_sp.get());
1360 }
1361 
1362 void
1363 Thread::DiscardThreadPlansUpToPlan (ThreadPlan *up_to_plan_ptr)
1364 {
1365     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1366     if (log)
1367         log->Printf("Discarding thread plans for thread tid = 0x%4.4" PRIx64 ", up to %p",
1368                     GetID(), static_cast<void*>(up_to_plan_ptr));
1369 
1370     int stack_size = m_plan_stack.size();
1371 
1372     // If the input plan is nullptr, discard all plans.  Otherwise make sure this plan is in the
1373     // stack, and if so discard up to and including it.
1374 
1375     if (up_to_plan_ptr == nullptr)
1376     {
1377         for (int i = stack_size - 1; i > 0; i--)
1378             DiscardPlan();
1379     }
1380     else
1381     {
1382         bool found_it = false;
1383         for (int i = stack_size - 1; i > 0; i--)
1384         {
1385             if (m_plan_stack[i].get() == up_to_plan_ptr)
1386                 found_it = true;
1387         }
1388         if (found_it)
1389         {
1390             bool last_one = false;
1391             for (int i = stack_size - 1; i > 0 && !last_one ; i--)
1392             {
1393                 if (GetCurrentPlan() == up_to_plan_ptr)
1394                     last_one = true;
1395                 DiscardPlan();
1396             }
1397         }
1398     }
1399 }
1400 
1401 void
1402 Thread::DiscardThreadPlans(bool force)
1403 {
1404     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1405     if (log)
1406     {
1407         log->Printf("Discarding thread plans for thread (tid = 0x%4.4" PRIx64 ", force %d)", GetID(), force);
1408     }
1409 
1410     if (force)
1411     {
1412         int stack_size = m_plan_stack.size();
1413         for (int i = stack_size - 1; i > 0; i--)
1414         {
1415             DiscardPlan();
1416         }
1417         return;
1418     }
1419 
1420     while (1)
1421     {
1422         int master_plan_idx;
1423         bool discard = true;
1424 
1425         // Find the first master plan, see if it wants discarding, and if yes discard up to it.
1426         for (master_plan_idx = m_plan_stack.size() - 1; master_plan_idx >= 0; master_plan_idx--)
1427         {
1428             if (m_plan_stack[master_plan_idx]->IsMasterPlan())
1429             {
1430                 discard = m_plan_stack[master_plan_idx]->OkayToDiscard();
1431                 break;
1432             }
1433         }
1434 
1435         if (discard)
1436         {
1437             // First pop all the dependent plans:
1438             for (int i = m_plan_stack.size() - 1; i > master_plan_idx; i--)
1439             {
1440                 // FIXME: Do we need a finalize here, or is the rule that "PrepareForStop"
1441                 // for the plan leaves it in a state that it is safe to pop the plan
1442                 // with no more notice?
1443                 DiscardPlan();
1444             }
1445 
1446             // Now discard the master plan itself.
1447             // The bottom-most plan never gets discarded.  "OkayToDiscard" for it means
1448             // discard it's dependent plans, but not it...
1449             if (master_plan_idx > 0)
1450             {
1451                 DiscardPlan();
1452             }
1453         }
1454         else
1455         {
1456             // If the master plan doesn't want to get discarded, then we're done.
1457             break;
1458         }
1459     }
1460 }
1461 
1462 bool
1463 Thread::PlanIsBasePlan (ThreadPlan *plan_ptr)
1464 {
1465     if (plan_ptr->IsBasePlan())
1466         return true;
1467     else if (m_plan_stack.size() == 0)
1468         return false;
1469     else
1470        return m_plan_stack[0].get() == plan_ptr;
1471 }
1472 
1473 Error
1474 Thread::UnwindInnermostExpression()
1475 {
1476     Error error;
1477     int stack_size = m_plan_stack.size();
1478 
1479     // If the input plan is nullptr, discard all plans.  Otherwise make sure this plan is in the
1480     // stack, and if so discard up to and including it.
1481 
1482     for (int i = stack_size - 1; i > 0; i--)
1483     {
1484         if (m_plan_stack[i]->GetKind() == ThreadPlan::eKindCallFunction)
1485         {
1486             DiscardThreadPlansUpToPlan(m_plan_stack[i].get());
1487             return error;
1488         }
1489     }
1490     error.SetErrorString("No expressions currently active on this thread");
1491     return error;
1492 }
1493 
1494 ThreadPlanSP
1495 Thread::QueueFundamentalPlan (bool abort_other_plans)
1496 {
1497     ThreadPlanSP thread_plan_sp (new ThreadPlanBase(*this));
1498     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1499     return thread_plan_sp;
1500 }
1501 
1502 ThreadPlanSP
1503 Thread::QueueThreadPlanForStepSingleInstruction(bool step_over,
1504                                                 bool abort_other_plans,
1505                                                 bool stop_other_threads)
1506 {
1507     ThreadPlanSP thread_plan_sp (new ThreadPlanStepInstruction (*this, step_over, stop_other_threads, eVoteNoOpinion, eVoteNoOpinion));
1508     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1509     return thread_plan_sp;
1510 }
1511 
1512 ThreadPlanSP
1513 Thread::QueueThreadPlanForStepOverRange(bool abort_other_plans,
1514                                         const AddressRange &range,
1515                                         const SymbolContext &addr_context,
1516                                         lldb::RunMode stop_other_threads,
1517                                         LazyBool step_out_avoids_code_withoug_debug_info)
1518 {
1519     ThreadPlanSP thread_plan_sp;
1520     thread_plan_sp.reset (new ThreadPlanStepOverRange (*this, range, addr_context, stop_other_threads, step_out_avoids_code_withoug_debug_info));
1521 
1522     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1523     return thread_plan_sp;
1524 }
1525 
1526 // Call the QueueThreadPlanForStepOverRange method which takes an address range.
1527 ThreadPlanSP
1528 Thread::QueueThreadPlanForStepOverRange(bool abort_other_plans,
1529                                         const LineEntry &line_entry,
1530                                         const SymbolContext &addr_context,
1531                                         lldb::RunMode stop_other_threads,
1532                                         LazyBool step_out_avoids_code_withoug_debug_info)
1533 {
1534     return QueueThreadPlanForStepOverRange (abort_other_plans,
1535                                             line_entry.GetSameLineContiguousAddressRange(),
1536                                             addr_context,
1537                                             stop_other_threads,
1538                                             step_out_avoids_code_withoug_debug_info);
1539 }
1540 
1541 ThreadPlanSP
1542 Thread::QueueThreadPlanForStepInRange(bool abort_other_plans,
1543                                       const AddressRange &range,
1544                                       const SymbolContext &addr_context,
1545                                       const char *step_in_target,
1546                                       lldb::RunMode stop_other_threads,
1547                                       LazyBool step_in_avoids_code_without_debug_info,
1548                                       LazyBool step_out_avoids_code_without_debug_info)
1549 {
1550     ThreadPlanSP thread_plan_sp (new ThreadPlanStepInRange (*this,
1551                                                              range,
1552                                                              addr_context,
1553                                                              stop_other_threads,
1554                                                              step_in_avoids_code_without_debug_info,
1555                                                              step_out_avoids_code_without_debug_info));
1556     ThreadPlanStepInRange *plan = static_cast<ThreadPlanStepInRange *>(thread_plan_sp.get());
1557 
1558     if (step_in_target)
1559         plan->SetStepInTarget(step_in_target);
1560 
1561     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1562     return thread_plan_sp;
1563 }
1564 
1565 // Call the QueueThreadPlanForStepInRange method which takes an address range.
1566 ThreadPlanSP
1567 Thread::QueueThreadPlanForStepInRange(bool abort_other_plans,
1568                                       const LineEntry &line_entry,
1569                                       const SymbolContext &addr_context,
1570                                       const char *step_in_target,
1571                                       lldb::RunMode stop_other_threads,
1572                                       LazyBool step_in_avoids_code_without_debug_info,
1573                                       LazyBool step_out_avoids_code_without_debug_info)
1574 {
1575     return QueueThreadPlanForStepInRange (abort_other_plans,
1576                                           line_entry.GetSameLineContiguousAddressRange(),
1577                                           addr_context,
1578                                           step_in_target,
1579                                           stop_other_threads,
1580                                           step_in_avoids_code_without_debug_info,
1581                                           step_out_avoids_code_without_debug_info);
1582 }
1583 
1584 
1585 ThreadPlanSP
1586 Thread::QueueThreadPlanForStepOut(bool abort_other_plans,
1587                                   SymbolContext *addr_context,
1588                                   bool first_insn,
1589                                   bool stop_other_threads,
1590                                   Vote stop_vote,
1591                                   Vote run_vote,
1592                                   uint32_t frame_idx,
1593                                   LazyBool step_out_avoids_code_without_debug_info)
1594 {
1595     ThreadPlanSP thread_plan_sp (new ThreadPlanStepOut (*this,
1596                                                         addr_context,
1597                                                         first_insn,
1598                                                         stop_other_threads,
1599                                                         stop_vote,
1600                                                         run_vote,
1601                                                         frame_idx,
1602                                                         step_out_avoids_code_without_debug_info));
1603 
1604     if (thread_plan_sp->ValidatePlan(nullptr))
1605     {
1606         QueueThreadPlan (thread_plan_sp, abort_other_plans);
1607         return thread_plan_sp;
1608     }
1609     else
1610     {
1611         return ThreadPlanSP();
1612     }
1613 }
1614 
1615 ThreadPlanSP
1616 Thread::QueueThreadPlanForStepOutNoShouldStop(bool abort_other_plans,
1617                                               SymbolContext *addr_context,
1618                                               bool first_insn,
1619                                               bool stop_other_threads,
1620                                               Vote stop_vote,
1621                                               Vote run_vote,
1622                                               uint32_t frame_idx,
1623                                               bool continue_to_next_branch)
1624 {
1625     ThreadPlanSP thread_plan_sp(new ThreadPlanStepOut (*this,
1626                                                         addr_context,
1627                                                         first_insn,
1628                                                         stop_other_threads,
1629                                                         stop_vote,
1630                                                         run_vote,
1631                                                         frame_idx,
1632                                                         eLazyBoolNo,
1633                                                         continue_to_next_branch));
1634 
1635     ThreadPlanStepOut *new_plan = static_cast<ThreadPlanStepOut *>(thread_plan_sp.get());
1636     new_plan->ClearShouldStopHereCallbacks();
1637 
1638     if (thread_plan_sp->ValidatePlan(nullptr))
1639     {
1640         QueueThreadPlan (thread_plan_sp, abort_other_plans);
1641         return thread_plan_sp;
1642     }
1643     else
1644     {
1645         return ThreadPlanSP();
1646     }
1647 }
1648 
1649 ThreadPlanSP
1650 Thread::QueueThreadPlanForStepThrough (StackID &return_stack_id, bool abort_other_plans, bool stop_other_threads)
1651 {
1652     ThreadPlanSP thread_plan_sp(new ThreadPlanStepThrough (*this, return_stack_id, stop_other_threads));
1653     if (!thread_plan_sp || !thread_plan_sp->ValidatePlan(nullptr))
1654         return ThreadPlanSP();
1655 
1656     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1657     return thread_plan_sp;
1658 }
1659 
1660 ThreadPlanSP
1661 Thread::QueueThreadPlanForRunToAddress (bool abort_other_plans,
1662                                         Address &target_addr,
1663                                         bool stop_other_threads)
1664 {
1665     ThreadPlanSP thread_plan_sp (new ThreadPlanRunToAddress (*this, target_addr, stop_other_threads));
1666     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1667     return thread_plan_sp;
1668 }
1669 
1670 ThreadPlanSP
1671 Thread::QueueThreadPlanForStepUntil (bool abort_other_plans,
1672                                      lldb::addr_t *address_list,
1673                                      size_t num_addresses,
1674                                      bool stop_other_threads,
1675                                      uint32_t frame_idx)
1676 {
1677     ThreadPlanSP thread_plan_sp (new ThreadPlanStepUntil (*this, address_list, num_addresses, stop_other_threads, frame_idx));
1678     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1679     return thread_plan_sp;
1680 
1681 }
1682 
1683 lldb::ThreadPlanSP
1684 Thread::QueueThreadPlanForStepScripted (bool abort_other_plans,
1685                                         const char *class_name,
1686                                         bool stop_other_threads)
1687 {
1688     ThreadPlanSP thread_plan_sp (new ThreadPlanPython (*this, class_name));
1689     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1690     // This seems a little funny, but I don't want to have to split up the constructor and the
1691     // DidPush in the scripted plan, that seems annoying.
1692     // That means the constructor has to be in DidPush.
1693     // So I have to validate the plan AFTER pushing it, and then take it off again...
1694     if (!thread_plan_sp->ValidatePlan(nullptr))
1695     {
1696         DiscardThreadPlansUpToPlan(thread_plan_sp);
1697         return ThreadPlanSP();
1698     }
1699     else
1700         return thread_plan_sp;
1701 }
1702 
1703 uint32_t
1704 Thread::GetIndexID () const
1705 {
1706     return m_index_id;
1707 }
1708 
1709 static void
1710 PrintPlanElement (Stream *s, const ThreadPlanSP &plan, lldb::DescriptionLevel desc_level, int32_t elem_idx)
1711 {
1712         s->IndentMore();
1713         s->Indent();
1714         s->Printf ("Element %d: ", elem_idx);
1715         plan->GetDescription (s, desc_level);
1716         s->EOL();
1717         s->IndentLess();
1718 }
1719 
1720 static void
1721 PrintPlanStack (Stream *s, const std::vector<lldb::ThreadPlanSP> &plan_stack, lldb::DescriptionLevel desc_level, bool include_internal)
1722 {
1723     int32_t print_idx = 0;
1724     for (ThreadPlanSP plan_sp : plan_stack)
1725     {
1726         if (include_internal || !plan_sp->GetPrivate())
1727         {
1728             PrintPlanElement (s, plan_sp, desc_level, print_idx++);
1729         }
1730     }
1731 }
1732 
1733 void
1734 Thread::DumpThreadPlans (Stream *s,
1735                          lldb::DescriptionLevel desc_level,
1736                          bool include_internal,
1737                          bool ignore_boring_threads) const
1738 {
1739     uint32_t stack_size;
1740 
1741     if (ignore_boring_threads)
1742     {
1743         uint32_t stack_size = m_plan_stack.size();
1744         uint32_t completed_stack_size = m_completed_plan_stack.size();
1745         uint32_t discarded_stack_size = m_discarded_plan_stack.size();
1746         if (stack_size == 1 && completed_stack_size == 0 && discarded_stack_size == 0)
1747         {
1748             s->Printf ("thread #%u: tid = 0x%4.4" PRIx64 "\n", GetIndexID(), GetID());
1749             s->IndentMore();
1750             s->Indent();
1751             s->Printf("No active thread plans\n");
1752             s->IndentLess();
1753             return;
1754         }
1755     }
1756 
1757     s->Indent();
1758     s->Printf ("thread #%u: tid = 0x%4.4" PRIx64 ":\n", GetIndexID(), GetID());
1759     s->IndentMore();
1760     s->Indent();
1761     s->Printf ("Active plan stack:\n");
1762     PrintPlanStack (s, m_plan_stack, desc_level, include_internal);
1763 
1764     stack_size = m_completed_plan_stack.size();
1765     if (stack_size > 0)
1766     {
1767         s->Indent();
1768         s->Printf ("Completed Plan Stack:\n");
1769         PrintPlanStack (s, m_completed_plan_stack, desc_level, include_internal);
1770     }
1771 
1772     stack_size = m_discarded_plan_stack.size();
1773     if (stack_size > 0)
1774     {
1775         s->Indent();
1776         s->Printf ("Discarded Plan Stack:\n");
1777         PrintPlanStack (s, m_discarded_plan_stack, desc_level, include_internal);
1778     }
1779 
1780     s->IndentLess();
1781 }
1782 
1783 TargetSP
1784 Thread::CalculateTarget ()
1785 {
1786     TargetSP target_sp;
1787     ProcessSP process_sp(GetProcess());
1788     if (process_sp)
1789         target_sp = process_sp->CalculateTarget();
1790     return target_sp;
1791 }
1792 
1793 ProcessSP
1794 Thread::CalculateProcess ()
1795 {
1796     return GetProcess();
1797 }
1798 
1799 ThreadSP
1800 Thread::CalculateThread ()
1801 {
1802     return shared_from_this();
1803 }
1804 
1805 StackFrameSP
1806 Thread::CalculateStackFrame ()
1807 {
1808     return StackFrameSP();
1809 }
1810 
1811 void
1812 Thread::CalculateExecutionContext (ExecutionContext &exe_ctx)
1813 {
1814     exe_ctx.SetContext (shared_from_this());
1815 }
1816 
1817 StackFrameListSP
1818 Thread::GetStackFrameList ()
1819 {
1820     StackFrameListSP frame_list_sp;
1821     Mutex::Locker locker(m_frame_mutex);
1822     if (m_curr_frames_sp)
1823     {
1824         frame_list_sp = m_curr_frames_sp;
1825     }
1826     else
1827     {
1828         frame_list_sp.reset(new StackFrameList (*this, m_prev_frames_sp, true));
1829         m_curr_frames_sp = frame_list_sp;
1830     }
1831     return frame_list_sp;
1832 }
1833 
1834 void
1835 Thread::ClearStackFrames ()
1836 {
1837     Mutex::Locker locker(m_frame_mutex);
1838 
1839     Unwind *unwinder = GetUnwinder ();
1840     if (unwinder)
1841         unwinder->Clear();
1842 
1843     // Only store away the old "reference" StackFrameList if we got all its frames:
1844     // FIXME: At some point we can try to splice in the frames we have fetched into
1845     // the new frame as we make it, but let's not try that now.
1846     if (m_curr_frames_sp && m_curr_frames_sp->GetAllFramesFetched())
1847         m_prev_frames_sp.swap (m_curr_frames_sp);
1848     m_curr_frames_sp.reset();
1849 
1850     m_extended_info.reset();
1851     m_extended_info_fetched = false;
1852 }
1853 
1854 lldb::StackFrameSP
1855 Thread::GetFrameWithConcreteFrameIndex (uint32_t unwind_idx)
1856 {
1857     return GetStackFrameList()->GetFrameWithConcreteFrameIndex (unwind_idx);
1858 }
1859 
1860 Error
1861 Thread::ReturnFromFrameWithIndex (uint32_t frame_idx, lldb::ValueObjectSP return_value_sp, bool broadcast)
1862 {
1863     StackFrameSP frame_sp = GetStackFrameAtIndex (frame_idx);
1864     Error return_error;
1865 
1866     if (!frame_sp)
1867     {
1868         return_error.SetErrorStringWithFormat("Could not find frame with index %d in thread 0x%" PRIx64 ".", frame_idx, GetID());
1869     }
1870 
1871     return ReturnFromFrame(frame_sp, return_value_sp, broadcast);
1872 }
1873 
1874 Error
1875 Thread::ReturnFromFrame (lldb::StackFrameSP frame_sp, lldb::ValueObjectSP return_value_sp, bool broadcast)
1876 {
1877     Error return_error;
1878 
1879     if (!frame_sp)
1880     {
1881         return_error.SetErrorString("Can't return to a null frame.");
1882         return return_error;
1883     }
1884 
1885     Thread *thread = frame_sp->GetThread().get();
1886     uint32_t older_frame_idx = frame_sp->GetFrameIndex() + 1;
1887     StackFrameSP older_frame_sp = thread->GetStackFrameAtIndex(older_frame_idx);
1888     if (!older_frame_sp)
1889     {
1890         return_error.SetErrorString("No older frame to return to.");
1891         return return_error;
1892     }
1893 
1894     if (return_value_sp)
1895     {
1896         lldb::ABISP abi = thread->GetProcess()->GetABI();
1897         if (!abi)
1898         {
1899             return_error.SetErrorString("Could not find ABI to set return value.");
1900             return return_error;
1901         }
1902         SymbolContext sc = frame_sp->GetSymbolContext(eSymbolContextFunction);
1903 
1904         // FIXME: ValueObject::Cast doesn't currently work correctly, at least not for scalars.
1905         // Turn that back on when that works.
1906         if (/* DISABLES CODE */ (0) && sc.function != nullptr)
1907         {
1908             Type *function_type = sc.function->GetType();
1909             if (function_type)
1910             {
1911                 CompilerType return_type = sc.function->GetCompilerType().GetFunctionReturnType();
1912                 if (return_type)
1913                 {
1914                     StreamString s;
1915                     return_type.DumpTypeDescription(&s);
1916                     ValueObjectSP cast_value_sp = return_value_sp->Cast(return_type);
1917                     if (cast_value_sp)
1918                     {
1919                         cast_value_sp->SetFormat(eFormatHex);
1920                         return_value_sp = cast_value_sp;
1921                     }
1922                 }
1923             }
1924         }
1925 
1926         return_error = abi->SetReturnValueObject(older_frame_sp, return_value_sp);
1927         if (!return_error.Success())
1928             return return_error;
1929     }
1930 
1931     // Now write the return registers for the chosen frame:
1932     // Note, we can't use ReadAllRegisterValues->WriteAllRegisterValues, since the read & write
1933     // cook their data
1934 
1935     StackFrameSP youngest_frame_sp = thread->GetStackFrameAtIndex(0);
1936     if (youngest_frame_sp)
1937     {
1938         lldb::RegisterContextSP reg_ctx_sp (youngest_frame_sp->GetRegisterContext());
1939         if (reg_ctx_sp)
1940         {
1941             bool copy_success = reg_ctx_sp->CopyFromRegisterContext(older_frame_sp->GetRegisterContext());
1942             if (copy_success)
1943             {
1944                 thread->DiscardThreadPlans(true);
1945                 thread->ClearStackFrames();
1946                 if (broadcast && EventTypeHasListeners(eBroadcastBitStackChanged))
1947                     BroadcastEvent(eBroadcastBitStackChanged, new ThreadEventData (this->shared_from_this()));
1948             }
1949             else
1950             {
1951                 return_error.SetErrorString("Could not reset register values.");
1952             }
1953         }
1954         else
1955         {
1956             return_error.SetErrorString("Frame has no register context.");
1957         }
1958     }
1959     else
1960     {
1961         return_error.SetErrorString("Returned past top frame.");
1962     }
1963     return return_error;
1964 }
1965 
1966 static void DumpAddressList (Stream &s, const std::vector<Address> &list, ExecutionContextScope *exe_scope)
1967 {
1968     for (size_t n=0;n<list.size();n++)
1969     {
1970         s << "\t";
1971         list[n].Dump (&s, exe_scope, Address::DumpStyleResolvedDescription, Address::DumpStyleSectionNameOffset);
1972         s << "\n";
1973     }
1974 }
1975 
1976 Error
1977 Thread::JumpToLine (const FileSpec &file, uint32_t line, bool can_leave_function, std::string *warnings)
1978 {
1979     ExecutionContext exe_ctx (GetStackFrameAtIndex(0));
1980     Target *target = exe_ctx.GetTargetPtr();
1981     TargetSP target_sp = exe_ctx.GetTargetSP();
1982     RegisterContext *reg_ctx = exe_ctx.GetRegisterContext();
1983     StackFrame *frame = exe_ctx.GetFramePtr();
1984     const SymbolContext &sc = frame->GetSymbolContext(eSymbolContextFunction);
1985 
1986     // Find candidate locations.
1987     std::vector<Address> candidates, within_function, outside_function;
1988     target->GetImages().FindAddressesForLine (target_sp, file, line, sc.function, within_function, outside_function);
1989 
1990     // If possible, we try and stay within the current function.
1991     // Within a function, we accept multiple locations (optimized code may do this,
1992     // there's no solution here so we do the best we can).
1993     // However if we're trying to leave the function, we don't know how to pick the
1994     // right location, so if there's more than one then we bail.
1995     if (!within_function.empty())
1996         candidates = within_function;
1997     else if (outside_function.size() == 1 && can_leave_function)
1998         candidates = outside_function;
1999 
2000     // Check if we got anything.
2001     if (candidates.empty())
2002     {
2003         if (outside_function.empty())
2004         {
2005             return Error("Cannot locate an address for %s:%i.",
2006                          file.GetFilename().AsCString(), line);
2007         }
2008         else if (outside_function.size() == 1)
2009         {
2010             return Error("%s:%i is outside the current function.",
2011                          file.GetFilename().AsCString(), line);
2012         }
2013         else
2014         {
2015             StreamString sstr;
2016             DumpAddressList(sstr, outside_function, target);
2017             return Error("%s:%i has multiple candidate locations:\n%s",
2018                          file.GetFilename().AsCString(), line, sstr.GetString().c_str());
2019         }
2020     }
2021 
2022     // Accept the first location, warn about any others.
2023     Address dest = candidates[0];
2024     if (warnings && candidates.size() > 1)
2025     {
2026         StreamString sstr;
2027         sstr.Printf("%s:%i appears multiple times in this function, selecting the first location:\n",
2028                      file.GetFilename().AsCString(), line);
2029         DumpAddressList(sstr, candidates, target);
2030         *warnings = sstr.GetString();
2031     }
2032 
2033     if (!reg_ctx->SetPC (dest))
2034         return Error("Cannot change PC to target address.");
2035 
2036     return Error();
2037 }
2038 
2039 void
2040 Thread::DumpUsingSettingsFormat (Stream &strm, uint32_t frame_idx)
2041 {
2042     ExecutionContext exe_ctx (shared_from_this());
2043     Process *process = exe_ctx.GetProcessPtr();
2044     if (process == nullptr)
2045         return;
2046 
2047     StackFrameSP frame_sp;
2048     SymbolContext frame_sc;
2049     if (frame_idx != LLDB_INVALID_FRAME_ID)
2050     {
2051         frame_sp = GetStackFrameAtIndex (frame_idx);
2052         if (frame_sp)
2053         {
2054             exe_ctx.SetFrameSP(frame_sp);
2055             frame_sc = frame_sp->GetSymbolContext(eSymbolContextEverything);
2056         }
2057     }
2058 
2059     const FormatEntity::Entry *thread_format = exe_ctx.GetTargetRef().GetDebugger().GetThreadFormat();
2060     assert (thread_format);
2061 
2062     FormatEntity::Format(*thread_format,
2063                          strm,
2064                          frame_sp ? &frame_sc : nullptr,
2065                          &exe_ctx,
2066                          nullptr,
2067                          nullptr,
2068                          false,
2069                          false);
2070 }
2071 
2072 void
2073 Thread::SettingsInitialize ()
2074 {
2075 }
2076 
2077 void
2078 Thread::SettingsTerminate ()
2079 {
2080 }
2081 
2082 lldb::addr_t
2083 Thread::GetThreadPointer ()
2084 {
2085     return LLDB_INVALID_ADDRESS;
2086 }
2087 
2088 addr_t
2089 Thread::GetThreadLocalData (const ModuleSP module)
2090 {
2091     // The default implementation is to ask the dynamic loader for it.
2092     // This can be overridden for specific platforms.
2093     DynamicLoader *loader = GetProcess()->GetDynamicLoader();
2094     if (loader)
2095         return loader->GetThreadLocalData (module, shared_from_this());
2096     else
2097         return LLDB_INVALID_ADDRESS;
2098 }
2099 
2100 bool
2101 Thread::SafeToCallFunctions ()
2102 {
2103     Process *process = GetProcess().get();
2104     if (process)
2105     {
2106         SystemRuntime *runtime = process->GetSystemRuntime ();
2107         if (runtime)
2108         {
2109             return runtime->SafeToCallFunctionsOnThisThread (shared_from_this());
2110         }
2111     }
2112     return true;
2113 }
2114 
2115 lldb::StackFrameSP
2116 Thread::GetStackFrameSPForStackFramePtr (StackFrame *stack_frame_ptr)
2117 {
2118     return GetStackFrameList()->GetStackFrameSPForStackFramePtr (stack_frame_ptr);
2119 }
2120 
2121 const char *
2122 Thread::StopReasonAsCString (lldb::StopReason reason)
2123 {
2124     switch (reason)
2125     {
2126     case eStopReasonInvalid:       return "invalid";
2127     case eStopReasonNone:          return "none";
2128     case eStopReasonTrace:         return "trace";
2129     case eStopReasonBreakpoint:    return "breakpoint";
2130     case eStopReasonWatchpoint:    return "watchpoint";
2131     case eStopReasonSignal:        return "signal";
2132     case eStopReasonException:     return "exception";
2133     case eStopReasonExec:          return "exec";
2134     case eStopReasonPlanComplete:  return "plan complete";
2135     case eStopReasonThreadExiting: return "thread exiting";
2136     case eStopReasonInstrumentation: return "instrumentation break";
2137     }
2138 
2139     static char unknown_state_string[64];
2140     snprintf(unknown_state_string, sizeof (unknown_state_string), "StopReason = %i", reason);
2141     return unknown_state_string;
2142 }
2143 
2144 const char *
2145 Thread::RunModeAsCString (lldb::RunMode mode)
2146 {
2147     switch (mode)
2148     {
2149     case eOnlyThisThread:     return "only this thread";
2150     case eAllThreads:         return "all threads";
2151     case eOnlyDuringStepping: return "only during stepping";
2152     }
2153 
2154     static char unknown_state_string[64];
2155     snprintf(unknown_state_string, sizeof (unknown_state_string), "RunMode = %i", mode);
2156     return unknown_state_string;
2157 }
2158 
2159 size_t
2160 Thread::GetStatus (Stream &strm, uint32_t start_frame, uint32_t num_frames, uint32_t num_frames_with_source)
2161 {
2162     ExecutionContext exe_ctx (shared_from_this());
2163     Target *target = exe_ctx.GetTargetPtr();
2164     Process *process = exe_ctx.GetProcessPtr();
2165     size_t num_frames_shown = 0;
2166     strm.Indent();
2167     bool is_selected = false;
2168     if (process)
2169     {
2170         if (process->GetThreadList().GetSelectedThread().get() == this)
2171             is_selected = true;
2172     }
2173     strm.Printf("%c ", is_selected ? '*' : ' ');
2174     if (target && target->GetDebugger().GetUseExternalEditor())
2175     {
2176         StackFrameSP frame_sp = GetStackFrameAtIndex(start_frame);
2177         if (frame_sp)
2178         {
2179             SymbolContext frame_sc(frame_sp->GetSymbolContext (eSymbolContextLineEntry));
2180             if (frame_sc.line_entry.line != 0 && frame_sc.line_entry.file)
2181             {
2182                 Host::OpenFileInExternalEditor (frame_sc.line_entry.file, frame_sc.line_entry.line);
2183             }
2184         }
2185     }
2186 
2187     DumpUsingSettingsFormat (strm, start_frame);
2188 
2189     if (num_frames > 0)
2190     {
2191         strm.IndentMore();
2192 
2193         const bool show_frame_info = true;
2194 
2195         const char *selected_frame_marker = nullptr;
2196         if (num_frames == 1 || (GetID() != GetProcess()->GetThreadList().GetSelectedThread()->GetID()))
2197             strm.IndentMore ();
2198         else
2199             selected_frame_marker = "* ";
2200 
2201         num_frames_shown = GetStackFrameList ()->GetStatus (strm,
2202                                                             start_frame,
2203                                                             num_frames,
2204                                                             show_frame_info,
2205                                                             num_frames_with_source,
2206                                                             selected_frame_marker);
2207         if (num_frames == 1)
2208             strm.IndentLess();
2209         strm.IndentLess();
2210     }
2211     return num_frames_shown;
2212 }
2213 
2214 bool
2215 Thread::GetDescription (Stream &strm, lldb::DescriptionLevel level, bool print_json_thread, bool print_json_stopinfo)
2216 {
2217     DumpUsingSettingsFormat (strm, 0);
2218     strm.Printf("\n");
2219 
2220     StructuredData::ObjectSP thread_info = GetExtendedInfo();
2221 
2222     if (print_json_thread || print_json_stopinfo)
2223     {
2224         if (thread_info && print_json_thread)
2225         {
2226             thread_info->Dump (strm);
2227             strm.Printf("\n");
2228         }
2229 
2230         if (print_json_stopinfo && m_stop_info_sp)
2231         {
2232             StructuredData::ObjectSP stop_info = m_stop_info_sp->GetExtendedInfo();
2233             if (stop_info)
2234             {
2235                 stop_info->Dump (strm);
2236                 strm.Printf("\n");
2237             }
2238         }
2239 
2240         return true;
2241     }
2242 
2243     if (thread_info)
2244     {
2245         StructuredData::ObjectSP activity = thread_info->GetObjectForDotSeparatedPath("activity");
2246         StructuredData::ObjectSP breadcrumb = thread_info->GetObjectForDotSeparatedPath("breadcrumb");
2247         StructuredData::ObjectSP messages = thread_info->GetObjectForDotSeparatedPath("trace_messages");
2248 
2249         bool printed_activity = false;
2250         if (activity && activity->GetType() == StructuredData::Type::eTypeDictionary)
2251         {
2252             StructuredData::Dictionary *activity_dict = activity->GetAsDictionary();
2253             StructuredData::ObjectSP id = activity_dict->GetValueForKey("id");
2254             StructuredData::ObjectSP name = activity_dict->GetValueForKey("name");
2255             if (name && name->GetType() == StructuredData::Type::eTypeString
2256                 && id && id->GetType() == StructuredData::Type::eTypeInteger)
2257             {
2258                 strm.Printf("  Activity '%s', 0x%" PRIx64 "\n", name->GetAsString()->GetValue().c_str(), id->GetAsInteger()->GetValue());
2259             }
2260             printed_activity = true;
2261         }
2262         bool printed_breadcrumb = false;
2263         if (breadcrumb && breadcrumb->GetType() == StructuredData::Type::eTypeDictionary)
2264         {
2265             if (printed_activity)
2266                 strm.Printf ("\n");
2267             StructuredData::Dictionary *breadcrumb_dict = breadcrumb->GetAsDictionary();
2268             StructuredData::ObjectSP breadcrumb_text = breadcrumb_dict->GetValueForKey ("name");
2269             if (breadcrumb_text && breadcrumb_text->GetType() == StructuredData::Type::eTypeString)
2270             {
2271                 strm.Printf ("  Current Breadcrumb: %s\n", breadcrumb_text->GetAsString()->GetValue().c_str());
2272             }
2273             printed_breadcrumb = true;
2274         }
2275         if (messages && messages->GetType() == StructuredData::Type::eTypeArray)
2276         {
2277             if (printed_breadcrumb)
2278                 strm.Printf("\n");
2279             StructuredData::Array *messages_array = messages->GetAsArray();
2280             const size_t msg_count = messages_array->GetSize();
2281             if (msg_count > 0)
2282             {
2283                 strm.Printf ("  %zu trace messages:\n", msg_count);
2284                 for (size_t i = 0; i < msg_count; i++)
2285                 {
2286                     StructuredData::ObjectSP message = messages_array->GetItemAtIndex(i);
2287                     if (message && message->GetType() == StructuredData::Type::eTypeDictionary)
2288                     {
2289                         StructuredData::Dictionary *message_dict = message->GetAsDictionary();
2290                         StructuredData::ObjectSP message_text = message_dict->GetValueForKey ("message");
2291                         if (message_text && message_text->GetType() == StructuredData::Type::eTypeString)
2292                         {
2293                             strm.Printf ("    %s\n", message_text->GetAsString()->GetValue().c_str());
2294                         }
2295                     }
2296                 }
2297             }
2298         }
2299     }
2300 
2301     return true;
2302 }
2303 
2304 size_t
2305 Thread::GetStackFrameStatus (Stream& strm,
2306                              uint32_t first_frame,
2307                              uint32_t num_frames,
2308                              bool show_frame_info,
2309                              uint32_t num_frames_with_source)
2310 {
2311     return GetStackFrameList()->GetStatus (strm,
2312                                            first_frame,
2313                                            num_frames,
2314                                            show_frame_info,
2315                                            num_frames_with_source);
2316 }
2317 
2318 Unwind *
2319 Thread::GetUnwinder ()
2320 {
2321     if (!m_unwinder_ap)
2322     {
2323         const ArchSpec target_arch (CalculateTarget()->GetArchitecture ());
2324         const llvm::Triple::ArchType machine = target_arch.GetMachine();
2325         switch (machine)
2326         {
2327             case llvm::Triple::x86_64:
2328             case llvm::Triple::x86:
2329             case llvm::Triple::arm:
2330             case llvm::Triple::aarch64:
2331             case llvm::Triple::thumb:
2332             case llvm::Triple::mips:
2333             case llvm::Triple::mipsel:
2334             case llvm::Triple::mips64:
2335             case llvm::Triple::mips64el:
2336             case llvm::Triple::ppc:
2337             case llvm::Triple::ppc64:
2338             case llvm::Triple::hexagon:
2339                 m_unwinder_ap.reset (new UnwindLLDB (*this));
2340                 break;
2341 
2342             default:
2343                 if (target_arch.GetTriple().getVendor() == llvm::Triple::Apple)
2344                     m_unwinder_ap.reset (new UnwindMacOSXFrameBackchain (*this));
2345                 break;
2346         }
2347     }
2348     return m_unwinder_ap.get();
2349 }
2350 
2351 void
2352 Thread::Flush ()
2353 {
2354     ClearStackFrames ();
2355     m_reg_context_sp.reset();
2356 }
2357 
2358 bool
2359 Thread::IsStillAtLastBreakpointHit ()
2360 {
2361     // If we are currently stopped at a breakpoint, always return that stopinfo and don't reset it.
2362     // This allows threads to maintain their breakpoint stopinfo, such as when thread-stepping in
2363     // multithreaded programs.
2364     if (m_stop_info_sp) {
2365         StopReason stop_reason = m_stop_info_sp->GetStopReason();
2366         if (stop_reason == lldb::eStopReasonBreakpoint) {
2367             uint64_t value = m_stop_info_sp->GetValue();
2368             lldb::RegisterContextSP reg_ctx_sp (GetRegisterContext());
2369             if (reg_ctx_sp)
2370             {
2371                 lldb::addr_t pc = reg_ctx_sp->GetPC();
2372                 BreakpointSiteSP bp_site_sp = GetProcess()->GetBreakpointSiteList().FindByAddress(pc);
2373                 if (bp_site_sp &&
2374                     static_cast<break_id_t>(value) == bp_site_sp->GetID())
2375                     return true;
2376             }
2377         }
2378     }
2379     return false;
2380 }
2381 
2382 Error
2383 Thread::StepIn (bool source_step,
2384                 LazyBool step_in_avoids_code_without_debug_info,
2385                 LazyBool step_out_avoids_code_without_debug_info)
2386 
2387 {
2388     Error error;
2389     Process *process = GetProcess().get();
2390     if (StateIsStoppedState (process->GetState(), true))
2391     {
2392         StackFrameSP frame_sp = GetStackFrameAtIndex (0);
2393         ThreadPlanSP new_plan_sp;
2394         const lldb::RunMode run_mode = eOnlyThisThread;
2395         const bool abort_other_plans = false;
2396 
2397         if (source_step && frame_sp && frame_sp->HasDebugInformation ())
2398         {
2399             SymbolContext sc(frame_sp->GetSymbolContext(eSymbolContextEverything));
2400             new_plan_sp = QueueThreadPlanForStepInRange(abort_other_plans,
2401                                                         sc.line_entry,
2402                                                         sc,
2403                                                         nullptr,
2404                                                         run_mode,
2405                                                         step_in_avoids_code_without_debug_info,
2406                                                         step_out_avoids_code_without_debug_info);
2407         }
2408         else
2409         {
2410             new_plan_sp = QueueThreadPlanForStepSingleInstruction (false,
2411                                                                    abort_other_plans,
2412                                                                    run_mode);
2413         }
2414 
2415         new_plan_sp->SetIsMasterPlan(true);
2416         new_plan_sp->SetOkayToDiscard(false);
2417 
2418         // Why do we need to set the current thread by ID here???
2419         process->GetThreadList().SetSelectedThreadByID (GetID());
2420         error = process->Resume();
2421     }
2422     else
2423     {
2424         error.SetErrorString("process not stopped");
2425     }
2426     return error;
2427 }
2428 
2429 Error
2430 Thread::StepOver (bool source_step,
2431                 LazyBool step_out_avoids_code_without_debug_info)
2432 {
2433     Error error;
2434     Process *process = GetProcess().get();
2435     if (StateIsStoppedState (process->GetState(), true))
2436     {
2437         StackFrameSP frame_sp = GetStackFrameAtIndex (0);
2438         ThreadPlanSP new_plan_sp;
2439 
2440         const lldb::RunMode run_mode = eOnlyThisThread;
2441         const bool abort_other_plans = false;
2442 
2443         if (source_step && frame_sp && frame_sp->HasDebugInformation ())
2444         {
2445             SymbolContext sc(frame_sp->GetSymbolContext(eSymbolContextEverything));
2446             new_plan_sp = QueueThreadPlanForStepOverRange (abort_other_plans,
2447                                                            sc.line_entry,
2448                                                            sc,
2449                                                            run_mode,
2450                                                            step_out_avoids_code_without_debug_info);
2451         }
2452         else
2453         {
2454             new_plan_sp = QueueThreadPlanForStepSingleInstruction (true,
2455                                                                    abort_other_plans,
2456                                                                    run_mode);
2457         }
2458 
2459         new_plan_sp->SetIsMasterPlan(true);
2460         new_plan_sp->SetOkayToDiscard(false);
2461 
2462         // Why do we need to set the current thread by ID here???
2463         process->GetThreadList().SetSelectedThreadByID (GetID());
2464         error = process->Resume();
2465     }
2466     else
2467     {
2468         error.SetErrorString("process not stopped");
2469     }
2470     return error;
2471 }
2472 
2473 Error
2474 Thread::StepOut ()
2475 {
2476     Error error;
2477     Process *process = GetProcess().get();
2478     if (StateIsStoppedState (process->GetState(), true))
2479     {
2480         const bool first_instruction = false;
2481         const bool stop_other_threads = false;
2482         const bool abort_other_plans = false;
2483 
2484         ThreadPlanSP new_plan_sp(QueueThreadPlanForStepOut(abort_other_plans,
2485                                                            nullptr,
2486                                                            first_instruction,
2487                                                            stop_other_threads,
2488                                                            eVoteYes,
2489                                                            eVoteNoOpinion,
2490                                                            0));
2491 
2492         new_plan_sp->SetIsMasterPlan(true);
2493         new_plan_sp->SetOkayToDiscard(false);
2494 
2495         // Why do we need to set the current thread by ID here???
2496         process->GetThreadList().SetSelectedThreadByID (GetID());
2497         error = process->Resume();
2498     }
2499     else
2500     {
2501         error.SetErrorString("process not stopped");
2502     }
2503     return error;
2504 }
2505