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, NULL, NULL, "If true, step-in will not stop in functions with no debug information." },
71     { "step-out-avoid-nodebug", OptionValue::eTypeBoolean, true, false, NULL, NULL, "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::", NULL, "A regular expression defining functions step-in won't stop in." },
74     { "step-avoid-libraries",  OptionValue::eTypeFileSpecList  , true , 0, NULL, NULL, "A list of libraries that source stepping won't stop in." },
75     { "trace-thread",       OptionValue::eTypeBoolean, false, false, NULL, NULL, "If true, this thread will single-step and log execution." },
76     {  NULL               , OptionValue::eTypeInvalid, false, 0    , NULL, NULL, NULL  }
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 (NULL, idx);
142 }
143 
144 FileSpecList &
145 ThreadProperties::GetLibrariesToAvoid() const
146 {
147     const uint32_t idx = ePropertyStepAvoidLibraries;
148     OptionValueFileSpecList *option_value = m_collection_sp->GetPropertyAtIndexAsOptionValueFileSpecList (NULL, 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 (NULL, 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 (NULL, 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 (NULL, 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 NULL;
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() == true)
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() == false)
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                         ;
705                         step_bp_plan_sp->SetPrivate (true);
706 
707                         if (GetCurrentPlan()->RunState() != eStateStepping)
708                         {
709                             ThreadPlanStepOverBreakpoint *step_bp_plan
710                                     = static_cast<ThreadPlanStepOverBreakpoint *>(step_bp_plan_sp.get());
711                             step_bp_plan->SetAutoContinue(true);
712                         }
713                         QueueThreadPlan (step_bp_plan_sp, false);
714                     }
715                 }
716             }
717         }
718     }
719 }
720 
721 bool
722 Thread::ShouldResume (StateType resume_state)
723 {
724     // At this point clear the completed plan stack.
725     m_completed_plan_stack.clear();
726     m_discarded_plan_stack.clear();
727     m_override_should_notify = eLazyBoolCalculate;
728 
729     StateType prev_resume_state = GetTemporaryResumeState();
730 
731     SetTemporaryResumeState(resume_state);
732 
733     lldb::ThreadSP backing_thread_sp (GetBackingThread ());
734     if (backing_thread_sp)
735         backing_thread_sp->SetTemporaryResumeState(resume_state);
736 
737     // Make sure m_stop_info_sp is valid.  Don't do this for threads we suspended in the previous run.
738     if (prev_resume_state != eStateSuspended)
739         GetPrivateStopInfo();
740 
741     // This is a little dubious, but we are trying to limit how often we actually fetch stop info from
742     // the target, 'cause that slows down single stepping.  So assume that if we got to the point where
743     // we're about to resume, and we haven't yet had to fetch the stop reason, then it doesn't need to know
744     // about the fact that we are resuming...
745     const uint32_t process_stop_id = GetProcess()->GetStopID();
746     if (m_stop_info_stop_id == process_stop_id &&
747         (m_stop_info_sp && m_stop_info_sp->IsValid()))
748     {
749         StopInfo *stop_info = GetPrivateStopInfo().get();
750         if (stop_info)
751             stop_info->WillResume (resume_state);
752     }
753 
754     // Tell all the plans that we are about to resume in case they need to clear any state.
755     // We distinguish between the plan on the top of the stack and the lower
756     // plans in case a plan needs to do any special business before it runs.
757 
758     bool need_to_resume = false;
759     ThreadPlan *plan_ptr = GetCurrentPlan();
760     if (plan_ptr)
761     {
762         need_to_resume = plan_ptr->WillResume(resume_state, true);
763 
764         while ((plan_ptr = GetPreviousPlan(plan_ptr)) != NULL)
765         {
766             plan_ptr->WillResume (resume_state, false);
767         }
768 
769         // If the WillResume for the plan says we are faking a resume, then it will have set an appropriate stop info.
770         // In that case, don't reset it here.
771 
772         if (need_to_resume && resume_state != eStateSuspended)
773         {
774             m_stop_info_sp.reset();
775         }
776     }
777 
778     if (need_to_resume)
779     {
780         ClearStackFrames();
781         // Let Thread subclasses do any special work they need to prior to resuming
782         WillResume (resume_state);
783     }
784 
785     return need_to_resume;
786 }
787 
788 void
789 Thread::DidResume ()
790 {
791     SetResumeSignal (LLDB_INVALID_SIGNAL_NUMBER);
792 }
793 
794 void
795 Thread::DidStop ()
796 {
797     SetState (eStateStopped);
798 }
799 
800 bool
801 Thread::ShouldStop (Event* event_ptr)
802 {
803     ThreadPlan *current_plan = GetCurrentPlan();
804 
805     bool should_stop = true;
806 
807     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
808 
809     if (GetResumeState () == eStateSuspended)
810     {
811         if (log)
812             log->Printf ("Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64 ", should_stop = 0 (ignore since thread was suspended)",
813                          __FUNCTION__, GetID (), GetProtocolID());
814         return false;
815     }
816 
817     if (GetTemporaryResumeState () == eStateSuspended)
818     {
819         if (log)
820             log->Printf ("Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64 ", should_stop = 0 (ignore since thread was suspended)",
821                          __FUNCTION__, GetID (), GetProtocolID());
822         return false;
823     }
824 
825     // Based on the current thread plan and process stop info, check if this
826     // thread caused the process to stop. NOTE: this must take place before
827     // the plan is moved from the current plan stack to the completed plan
828     // stack.
829     if (ThreadStoppedForAReason() == false)
830     {
831         if (log)
832             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)",
833                          __FUNCTION__, GetID (), GetProtocolID(),
834                          GetRegisterContext() ? GetRegisterContext()->GetPC() : LLDB_INVALID_ADDRESS);
835         return false;
836     }
837 
838     if (log)
839     {
840         log->Printf ("Thread::%s(%p) for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64 ", pc = 0x%16.16" PRIx64,
841                      __FUNCTION__, static_cast<void*>(this), GetID (),
842                      GetProtocolID (),
843                      GetRegisterContext()
844                         ? GetRegisterContext()->GetPC()
845                         : LLDB_INVALID_ADDRESS);
846         log->Printf ("^^^^^^^^ Thread::ShouldStop Begin ^^^^^^^^");
847         StreamString s;
848         s.IndentMore();
849         DumpThreadPlans(&s);
850         log->Printf ("Plan stack initial state:\n%s", s.GetData());
851     }
852 
853     // The top most plan always gets to do the trace log...
854     current_plan->DoTraceLog ();
855 
856     // First query the stop info's ShouldStopSynchronous.  This handles "synchronous" stop reasons, for example the breakpoint
857     // command on internal breakpoints.  If a synchronous stop reason says we should not stop, then we don't have to
858     // do any more work on this stop.
859     StopInfoSP private_stop_info (GetPrivateStopInfo());
860     if (private_stop_info && private_stop_info->ShouldStopSynchronous(event_ptr) == false)
861     {
862         if (log)
863             log->Printf ("StopInfo::ShouldStop async callback says we should not stop, returning ShouldStop of false.");
864         return false;
865     }
866 
867     // If we've already been restarted, don't query the plans since the state they would examine is not current.
868     if (Process::ProcessEventData::GetRestartedFromEvent(event_ptr))
869         return false;
870 
871     // Before the plans see the state of the world, calculate the current inlined depth.
872     GetStackFrameList()->CalculateCurrentInlinedDepth();
873 
874     // If the base plan doesn't understand why we stopped, then we have to find a plan that does.
875     // If that plan is still working, then we don't need to do any more work.  If the plan that explains
876     // the stop is done, then we should pop all the plans below it, and pop it, and then let the plans above it decide
877     // whether they still need to do more work.
878 
879     bool done_processing_current_plan = false;
880 
881     if (!current_plan->PlanExplainsStop(event_ptr))
882     {
883         if (current_plan->TracerExplainsStop())
884         {
885             done_processing_current_plan = true;
886             should_stop = false;
887         }
888         else
889         {
890             // If the current plan doesn't explain the stop, then find one that
891             // does and let it handle the situation.
892             ThreadPlan *plan_ptr = current_plan;
893             while ((plan_ptr = GetPreviousPlan(plan_ptr)) != NULL)
894             {
895                 if (plan_ptr->PlanExplainsStop(event_ptr))
896                 {
897                     should_stop = plan_ptr->ShouldStop (event_ptr);
898 
899                     // plan_ptr explains the stop, next check whether plan_ptr is done, if so, then we should take it
900                     // and all the plans below it off the stack.
901 
902                     if (plan_ptr->MischiefManaged())
903                     {
904                         // We're going to pop the plans up to and including the plan that explains the stop.
905                         ThreadPlan *prev_plan_ptr = GetPreviousPlan (plan_ptr);
906 
907                         do
908                         {
909                             if (should_stop)
910                                 current_plan->WillStop();
911                             PopPlan();
912                         }
913                         while ((current_plan = GetCurrentPlan()) != prev_plan_ptr);
914                         // Now, if the responsible plan was not "Okay to discard" then we're done,
915                         // otherwise we forward this to the next plan in the stack below.
916                         if (plan_ptr->IsMasterPlan() && !plan_ptr->OkayToDiscard())
917                             done_processing_current_plan = true;
918                         else
919                             done_processing_current_plan = false;
920                     }
921                     else
922                         done_processing_current_plan = true;
923 
924                     break;
925                 }
926             }
927         }
928     }
929 
930     if (!done_processing_current_plan)
931     {
932         bool over_ride_stop = current_plan->ShouldAutoContinue(event_ptr);
933 
934         if (log)
935             log->Printf("Plan %s explains stop, auto-continue %i.",
936                         current_plan->GetName(), over_ride_stop);
937 
938         // We're starting from the base plan, so just let it decide;
939         if (PlanIsBasePlan(current_plan))
940         {
941             should_stop = current_plan->ShouldStop (event_ptr);
942             if (log)
943                 log->Printf("Base plan says should stop: %i.", should_stop);
944         }
945         else
946         {
947             // Otherwise, don't let the base plan override what the other plans say to do, since
948             // presumably if there were other plans they would know what to do...
949             while (1)
950             {
951                 if (PlanIsBasePlan(current_plan))
952                     break;
953 
954                 should_stop = current_plan->ShouldStop(event_ptr);
955                 if (log)
956                     log->Printf("Plan %s should stop: %d.",
957                                 current_plan->GetName(), should_stop);
958                 if (current_plan->MischiefManaged())
959                 {
960                     if (should_stop)
961                         current_plan->WillStop();
962 
963                     // If a Master Plan wants to stop, and wants to stick on the stack, we let it.
964                     // Otherwise, see if the plan's parent wants to stop.
965 
966                     if (should_stop && current_plan->IsMasterPlan() && !current_plan->OkayToDiscard())
967                     {
968                         PopPlan();
969                         break;
970                     }
971                     else
972                     {
973                         PopPlan();
974 
975                         current_plan = GetCurrentPlan();
976                         if (current_plan == NULL)
977                         {
978                             break;
979                         }
980                     }
981                 }
982                 else
983                 {
984                     break;
985                 }
986             }
987         }
988 
989         if (over_ride_stop)
990             should_stop = false;
991     }
992 
993     // One other potential problem is that we set up a master plan, then stop in before it is complete - for instance
994     // by hitting a breakpoint during a step-over - then do some step/finish/etc operations that wind up
995     // past the end point condition of the initial plan.  We don't want to strand the original plan on the stack,
996     // This code clears stale plans off the stack.
997 
998     if (should_stop)
999     {
1000         ThreadPlan *plan_ptr = GetCurrentPlan();
1001         while (!PlanIsBasePlan(plan_ptr))
1002         {
1003             bool stale = plan_ptr->IsPlanStale ();
1004             ThreadPlan *examined_plan = plan_ptr;
1005             plan_ptr = GetPreviousPlan (examined_plan);
1006 
1007             if (stale)
1008             {
1009                 if (log)
1010                     log->Printf("Plan %s being discarded in cleanup, it says it is already done.",
1011                                 examined_plan->GetName());
1012                 DiscardThreadPlansUpToPlan(examined_plan);
1013             }
1014         }
1015     }
1016 
1017     if (log)
1018     {
1019         StreamString s;
1020         s.IndentMore();
1021         DumpThreadPlans(&s);
1022         log->Printf ("Plan stack final state:\n%s", s.GetData());
1023         log->Printf ("vvvvvvvv Thread::ShouldStop End (returning %i) vvvvvvvv", should_stop);
1024     }
1025     return should_stop;
1026 }
1027 
1028 Vote
1029 Thread::ShouldReportStop (Event* event_ptr)
1030 {
1031     StateType thread_state = GetResumeState ();
1032     StateType temp_thread_state = GetTemporaryResumeState();
1033 
1034     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1035 
1036     if (thread_state == eStateSuspended || thread_state == eStateInvalid)
1037     {
1038         if (log)
1039             log->Printf ("Thread::ShouldReportStop() tid = 0x%4.4" PRIx64 ": returning vote %i (state was suspended or invalid)", GetID(), eVoteNoOpinion);
1040         return eVoteNoOpinion;
1041     }
1042 
1043     if (temp_thread_state == eStateSuspended || temp_thread_state == eStateInvalid)
1044     {
1045         if (log)
1046             log->Printf ("Thread::ShouldReportStop() tid = 0x%4.4" PRIx64 ": returning vote %i (temporary state was suspended or invalid)", GetID(), eVoteNoOpinion);
1047         return eVoteNoOpinion;
1048     }
1049 
1050     if (!ThreadStoppedForAReason())
1051     {
1052         if (log)
1053             log->Printf ("Thread::ShouldReportStop() tid = 0x%4.4" PRIx64 ": returning vote %i (thread didn't stop for a reason.)", GetID(), eVoteNoOpinion);
1054         return eVoteNoOpinion;
1055     }
1056 
1057     if (m_completed_plan_stack.size() > 0)
1058     {
1059         // Don't use GetCompletedPlan here, since that suppresses private plans.
1060         if (log)
1061             log->Printf ("Thread::ShouldReportStop() tid = 0x%4.4" PRIx64 ": returning vote  for complete stack's back plan", GetID());
1062         return m_completed_plan_stack.back()->ShouldReportStop (event_ptr);
1063     }
1064     else
1065     {
1066         Vote thread_vote = eVoteNoOpinion;
1067         ThreadPlan *plan_ptr = GetCurrentPlan();
1068         while (1)
1069         {
1070             if (plan_ptr->PlanExplainsStop(event_ptr))
1071             {
1072                 thread_vote = plan_ptr->ShouldReportStop(event_ptr);
1073                 break;
1074             }
1075             if (PlanIsBasePlan(plan_ptr))
1076                 break;
1077             else
1078                 plan_ptr = GetPreviousPlan(plan_ptr);
1079         }
1080         if (log)
1081             log->Printf ("Thread::ShouldReportStop() tid = 0x%4.4" PRIx64 ": returning vote %i for current plan", GetID(), thread_vote);
1082 
1083         return thread_vote;
1084     }
1085 }
1086 
1087 Vote
1088 Thread::ShouldReportRun (Event* event_ptr)
1089 {
1090     StateType thread_state = GetResumeState ();
1091 
1092     if (thread_state == eStateSuspended
1093             || thread_state == eStateInvalid)
1094     {
1095         return eVoteNoOpinion;
1096     }
1097 
1098     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1099     if (m_completed_plan_stack.size() > 0)
1100     {
1101         // Don't use GetCompletedPlan here, since that suppresses private plans.
1102         if (log)
1103             log->Printf ("Current Plan for thread %d(%p) (0x%4.4" PRIx64 ", %s): %s being asked whether we should report run.",
1104                          GetIndexID(), static_cast<void*>(this), GetID(),
1105                          StateAsCString(GetTemporaryResumeState()),
1106                          m_completed_plan_stack.back()->GetName());
1107 
1108         return m_completed_plan_stack.back()->ShouldReportRun (event_ptr);
1109     }
1110     else
1111     {
1112         if (log)
1113             log->Printf ("Current Plan for thread %d(%p) (0x%4.4" PRIx64 ", %s): %s being asked whether we should report run.",
1114                          GetIndexID(), static_cast<void*>(this), GetID(),
1115                          StateAsCString(GetTemporaryResumeState()),
1116                          GetCurrentPlan()->GetName());
1117 
1118         return GetCurrentPlan()->ShouldReportRun (event_ptr);
1119      }
1120 }
1121 
1122 bool
1123 Thread::MatchesSpec (const ThreadSpec *spec)
1124 {
1125     if (spec == NULL)
1126         return true;
1127 
1128     return spec->ThreadPassesBasicTests(*this);
1129 }
1130 
1131 void
1132 Thread::PushPlan (ThreadPlanSP &thread_plan_sp)
1133 {
1134     if (thread_plan_sp)
1135     {
1136         // If the thread plan doesn't already have a tracer, give it its parent's tracer:
1137         if (!thread_plan_sp->GetThreadPlanTracer())
1138             thread_plan_sp->SetThreadPlanTracer(m_plan_stack.back()->GetThreadPlanTracer());
1139         m_plan_stack.push_back (thread_plan_sp);
1140 
1141         thread_plan_sp->DidPush();
1142 
1143         Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1144         if (log)
1145         {
1146             StreamString s;
1147             thread_plan_sp->GetDescription (&s, lldb::eDescriptionLevelFull);
1148             log->Printf("Thread::PushPlan(0x%p): \"%s\", tid = 0x%4.4" PRIx64 ".",
1149                         static_cast<void*>(this), s.GetData(),
1150                         thread_plan_sp->GetThread().GetID());
1151         }
1152     }
1153 }
1154 
1155 void
1156 Thread::PopPlan ()
1157 {
1158     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1159 
1160     if (m_plan_stack.size() <= 1)
1161         return;
1162     else
1163     {
1164         ThreadPlanSP &plan = m_plan_stack.back();
1165         if (log)
1166         {
1167             log->Printf("Popping plan: \"%s\", tid = 0x%4.4" PRIx64 ".", plan->GetName(), plan->GetThread().GetID());
1168         }
1169         m_completed_plan_stack.push_back (plan);
1170         plan->WillPop();
1171         m_plan_stack.pop_back();
1172     }
1173 }
1174 
1175 void
1176 Thread::DiscardPlan ()
1177 {
1178     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1179     if (m_plan_stack.size() > 1)
1180     {
1181         ThreadPlanSP &plan = m_plan_stack.back();
1182         if (log)
1183             log->Printf("Discarding plan: \"%s\", tid = 0x%4.4" PRIx64 ".", plan->GetName(), plan->GetThread().GetID());
1184 
1185         m_discarded_plan_stack.push_back (plan);
1186         plan->WillPop();
1187         m_plan_stack.pop_back();
1188     }
1189 }
1190 
1191 ThreadPlan *
1192 Thread::GetCurrentPlan ()
1193 {
1194     // There will always be at least the base plan.  If somebody is mucking with a
1195     // thread with an empty plan stack, we should assert right away.
1196     if (m_plan_stack.empty())
1197         return NULL;
1198     return m_plan_stack.back().get();
1199 }
1200 
1201 ThreadPlanSP
1202 Thread::GetCompletedPlan ()
1203 {
1204     ThreadPlanSP empty_plan_sp;
1205     if (!m_completed_plan_stack.empty())
1206     {
1207         for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--)
1208         {
1209             ThreadPlanSP completed_plan_sp;
1210             completed_plan_sp = m_completed_plan_stack[i];
1211             if (!completed_plan_sp->GetPrivate ())
1212             return completed_plan_sp;
1213         }
1214     }
1215     return empty_plan_sp;
1216 }
1217 
1218 ValueObjectSP
1219 Thread::GetReturnValueObject ()
1220 {
1221     if (!m_completed_plan_stack.empty())
1222     {
1223         for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--)
1224         {
1225             ValueObjectSP return_valobj_sp;
1226             return_valobj_sp = m_completed_plan_stack[i]->GetReturnValueObject();
1227             if (return_valobj_sp)
1228                 return return_valobj_sp;
1229         }
1230     }
1231     return ValueObjectSP();
1232 }
1233 
1234 ExpressionVariableSP
1235 Thread::GetExpressionVariable ()
1236 {
1237     if (!m_completed_plan_stack.empty())
1238     {
1239         for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--)
1240         {
1241             ExpressionVariableSP expression_variable_sp;
1242             expression_variable_sp = m_completed_plan_stack[i]->GetExpressionVariable();
1243             if (expression_variable_sp)
1244                 return expression_variable_sp;
1245         }
1246     }
1247     return ExpressionVariableSP();
1248 }
1249 
1250 bool
1251 Thread::IsThreadPlanDone (ThreadPlan *plan)
1252 {
1253     if (!m_completed_plan_stack.empty())
1254     {
1255         for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--)
1256         {
1257             if (m_completed_plan_stack[i].get() == plan)
1258                 return true;
1259         }
1260     }
1261     return false;
1262 }
1263 
1264 bool
1265 Thread::WasThreadPlanDiscarded (ThreadPlan *plan)
1266 {
1267     if (!m_discarded_plan_stack.empty())
1268     {
1269         for (int i = m_discarded_plan_stack.size() - 1; i >= 0; i--)
1270         {
1271             if (m_discarded_plan_stack[i].get() == plan)
1272                 return true;
1273         }
1274     }
1275     return false;
1276 }
1277 
1278 ThreadPlan *
1279 Thread::GetPreviousPlan (ThreadPlan *current_plan)
1280 {
1281     if (current_plan == NULL)
1282         return NULL;
1283 
1284     int stack_size = m_completed_plan_stack.size();
1285     for (int i = stack_size - 1; i > 0; i--)
1286     {
1287         if (current_plan == m_completed_plan_stack[i].get())
1288             return m_completed_plan_stack[i-1].get();
1289     }
1290 
1291     if (stack_size > 0 && m_completed_plan_stack[0].get() == current_plan)
1292     {
1293         if (m_plan_stack.size() > 0)
1294             return m_plan_stack.back().get();
1295         else
1296             return NULL;
1297     }
1298 
1299     stack_size = m_plan_stack.size();
1300     for (int i = stack_size - 1; i > 0; i--)
1301     {
1302         if (current_plan == m_plan_stack[i].get())
1303             return m_plan_stack[i-1].get();
1304     }
1305     return NULL;
1306 }
1307 
1308 void
1309 Thread::QueueThreadPlan (ThreadPlanSP &thread_plan_sp, bool abort_other_plans)
1310 {
1311     if (abort_other_plans)
1312        DiscardThreadPlans(true);
1313 
1314     PushPlan (thread_plan_sp);
1315 }
1316 
1317 void
1318 Thread::EnableTracer (bool value, bool single_stepping)
1319 {
1320     int stack_size = m_plan_stack.size();
1321     for (int i = 0; i < stack_size; i++)
1322     {
1323         if (m_plan_stack[i]->GetThreadPlanTracer())
1324         {
1325             m_plan_stack[i]->GetThreadPlanTracer()->EnableTracing(value);
1326             m_plan_stack[i]->GetThreadPlanTracer()->EnableSingleStep(single_stepping);
1327         }
1328     }
1329 }
1330 
1331 void
1332 Thread::SetTracer (lldb::ThreadPlanTracerSP &tracer_sp)
1333 {
1334     int stack_size = m_plan_stack.size();
1335     for (int i = 0; i < stack_size; i++)
1336         m_plan_stack[i]->SetThreadPlanTracer(tracer_sp);
1337 }
1338 
1339 bool
1340 Thread::DiscardUserThreadPlansUpToIndex (uint32_t thread_index)
1341 {
1342     // Count the user thread plans from the back end to get the number of the one we want
1343     // to discard:
1344 
1345     uint32_t idx = 0;
1346     ThreadPlan *up_to_plan_ptr = nullptr;
1347 
1348     for (ThreadPlanSP plan_sp : m_plan_stack)
1349     {
1350         if (plan_sp->GetPrivate())
1351             continue;
1352         if (idx == thread_index)
1353         {
1354             up_to_plan_ptr = plan_sp.get();
1355             break;
1356         }
1357         else
1358             idx++;
1359     }
1360 
1361     if (up_to_plan_ptr == nullptr)
1362         return false;
1363 
1364     DiscardThreadPlansUpToPlan(up_to_plan_ptr);
1365     return true;
1366 }
1367 
1368 void
1369 Thread::DiscardThreadPlansUpToPlan (lldb::ThreadPlanSP &up_to_plan_sp)
1370 {
1371     DiscardThreadPlansUpToPlan (up_to_plan_sp.get());
1372 }
1373 
1374 void
1375 Thread::DiscardThreadPlansUpToPlan (ThreadPlan *up_to_plan_ptr)
1376 {
1377     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1378     if (log)
1379         log->Printf("Discarding thread plans for thread tid = 0x%4.4" PRIx64 ", up to %p",
1380                     GetID(), static_cast<void*>(up_to_plan_ptr));
1381 
1382     int stack_size = m_plan_stack.size();
1383 
1384     // If the input plan is NULL, discard all plans.  Otherwise make sure this plan is in the
1385     // stack, and if so discard up to and including it.
1386 
1387     if (up_to_plan_ptr == NULL)
1388     {
1389         for (int i = stack_size - 1; i > 0; i--)
1390             DiscardPlan();
1391     }
1392     else
1393     {
1394         bool found_it = false;
1395         for (int i = stack_size - 1; i > 0; i--)
1396         {
1397             if (m_plan_stack[i].get() == up_to_plan_ptr)
1398                 found_it = true;
1399         }
1400         if (found_it)
1401         {
1402             bool last_one = false;
1403             for (int i = stack_size - 1; i > 0 && !last_one ; i--)
1404             {
1405                 if (GetCurrentPlan() == up_to_plan_ptr)
1406                     last_one = true;
1407                 DiscardPlan();
1408             }
1409         }
1410     }
1411 }
1412 
1413 void
1414 Thread::DiscardThreadPlans(bool force)
1415 {
1416     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
1417     if (log)
1418     {
1419         log->Printf("Discarding thread plans for thread (tid = 0x%4.4" PRIx64 ", force %d)", GetID(), force);
1420     }
1421 
1422     if (force)
1423     {
1424         int stack_size = m_plan_stack.size();
1425         for (int i = stack_size - 1; i > 0; i--)
1426         {
1427             DiscardPlan();
1428         }
1429         return;
1430     }
1431 
1432     while (1)
1433     {
1434         int master_plan_idx;
1435         bool discard = true;
1436 
1437         // Find the first master plan, see if it wants discarding, and if yes discard up to it.
1438         for (master_plan_idx = m_plan_stack.size() - 1; master_plan_idx >= 0; master_plan_idx--)
1439         {
1440             if (m_plan_stack[master_plan_idx]->IsMasterPlan())
1441             {
1442                 discard = m_plan_stack[master_plan_idx]->OkayToDiscard();
1443                 break;
1444             }
1445         }
1446 
1447         if (discard)
1448         {
1449             // First pop all the dependent plans:
1450             for (int i = m_plan_stack.size() - 1; i > master_plan_idx; i--)
1451             {
1452                 // FIXME: Do we need a finalize here, or is the rule that "PrepareForStop"
1453                 // for the plan leaves it in a state that it is safe to pop the plan
1454                 // with no more notice?
1455                 DiscardPlan();
1456             }
1457 
1458             // Now discard the master plan itself.
1459             // The bottom-most plan never gets discarded.  "OkayToDiscard" for it means
1460             // discard it's dependent plans, but not it...
1461             if (master_plan_idx > 0)
1462             {
1463                 DiscardPlan();
1464             }
1465         }
1466         else
1467         {
1468             // If the master plan doesn't want to get discarded, then we're done.
1469             break;
1470         }
1471     }
1472 }
1473 
1474 bool
1475 Thread::PlanIsBasePlan (ThreadPlan *plan_ptr)
1476 {
1477     if (plan_ptr->IsBasePlan())
1478         return true;
1479     else if (m_plan_stack.size() == 0)
1480         return false;
1481     else
1482        return m_plan_stack[0].get() == plan_ptr;
1483 }
1484 
1485 Error
1486 Thread::UnwindInnermostExpression()
1487 {
1488     Error error;
1489     int stack_size = m_plan_stack.size();
1490 
1491     // If the input plan is NULL, discard all plans.  Otherwise make sure this plan is in the
1492     // stack, and if so discard up to and including it.
1493 
1494     for (int i = stack_size - 1; i > 0; i--)
1495     {
1496         if (m_plan_stack[i]->GetKind() == ThreadPlan::eKindCallFunction)
1497         {
1498             DiscardThreadPlansUpToPlan(m_plan_stack[i].get());
1499             return error;
1500         }
1501     }
1502     error.SetErrorString("No expressions currently active on this thread");
1503     return error;
1504 }
1505 
1506 ThreadPlanSP
1507 Thread::QueueFundamentalPlan (bool abort_other_plans)
1508 {
1509     ThreadPlanSP thread_plan_sp (new ThreadPlanBase(*this));
1510     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1511     return thread_plan_sp;
1512 }
1513 
1514 ThreadPlanSP
1515 Thread::QueueThreadPlanForStepSingleInstruction(bool step_over,
1516                                                 bool abort_other_plans,
1517                                                 bool stop_other_threads)
1518 {
1519     ThreadPlanSP thread_plan_sp (new ThreadPlanStepInstruction (*this, step_over, stop_other_threads, eVoteNoOpinion, eVoteNoOpinion));
1520     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1521     return thread_plan_sp;
1522 }
1523 
1524 ThreadPlanSP
1525 Thread::QueueThreadPlanForStepOverRange(bool abort_other_plans,
1526                                         const AddressRange &range,
1527                                         const SymbolContext &addr_context,
1528                                         lldb::RunMode stop_other_threads,
1529                                         LazyBool step_out_avoids_code_withoug_debug_info)
1530 {
1531     ThreadPlanSP thread_plan_sp;
1532     thread_plan_sp.reset (new ThreadPlanStepOverRange (*this, range, addr_context, stop_other_threads, step_out_avoids_code_withoug_debug_info));
1533 
1534     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1535     return thread_plan_sp;
1536 }
1537 
1538 ThreadPlanSP
1539 Thread::QueueThreadPlanForStepInRange(bool abort_other_plans,
1540                                       const AddressRange &range,
1541                                       const SymbolContext &addr_context,
1542                                       const char *step_in_target,
1543                                       lldb::RunMode stop_other_threads,
1544                                       LazyBool step_in_avoids_code_without_debug_info,
1545                                       LazyBool step_out_avoids_code_without_debug_info)
1546 {
1547     ThreadPlanSP thread_plan_sp (new ThreadPlanStepInRange (*this,
1548                                                              range,
1549                                                              addr_context,
1550                                                              stop_other_threads,
1551                                                              step_in_avoids_code_without_debug_info,
1552                                                              step_out_avoids_code_without_debug_info));
1553     ThreadPlanStepInRange *plan = static_cast<ThreadPlanStepInRange *>(thread_plan_sp.get());
1554 
1555     if (step_in_target)
1556         plan->SetStepInTarget(step_in_target);
1557 
1558     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1559     return thread_plan_sp;
1560 }
1561 
1562 ThreadPlanSP
1563 Thread::QueueThreadPlanForStepOut(bool abort_other_plans,
1564                                   SymbolContext *addr_context,
1565                                   bool first_insn,
1566                                   bool stop_other_threads,
1567                                   Vote stop_vote,
1568                                   Vote run_vote,
1569                                   uint32_t frame_idx,
1570                                   LazyBool step_out_avoids_code_withoug_debug_info)
1571 {
1572     ThreadPlanSP thread_plan_sp (new ThreadPlanStepOut (*this,
1573                                                         addr_context,
1574                                                         first_insn,
1575                                                         stop_other_threads,
1576                                                         stop_vote,
1577                                                         run_vote,
1578                                                         frame_idx,
1579                                                         step_out_avoids_code_withoug_debug_info));
1580 
1581     if (thread_plan_sp->ValidatePlan(NULL))
1582     {
1583         QueueThreadPlan (thread_plan_sp, abort_other_plans);
1584         return thread_plan_sp;
1585     }
1586     else
1587     {
1588         return ThreadPlanSP();
1589     }
1590 }
1591 
1592 ThreadPlanSP
1593 Thread::QueueThreadPlanForStepOutNoShouldStop(bool abort_other_plans,
1594                                               SymbolContext *addr_context,
1595                                               bool first_insn,
1596                                               bool stop_other_threads,
1597                                               Vote stop_vote,
1598                                               Vote run_vote,
1599                                               uint32_t frame_idx)
1600 {
1601     ThreadPlanSP thread_plan_sp(new ThreadPlanStepOut (*this,
1602                                                         addr_context,
1603                                                         first_insn,
1604                                                         stop_other_threads,
1605                                                         stop_vote,
1606                                                         run_vote,
1607                                                         frame_idx,
1608                                                         eLazyBoolNo));
1609 
1610     ThreadPlanStepOut *new_plan = static_cast<ThreadPlanStepOut *>(thread_plan_sp.get());
1611     new_plan->ClearShouldStopHereCallbacks();
1612 
1613     if (thread_plan_sp->ValidatePlan(NULL))
1614     {
1615         QueueThreadPlan (thread_plan_sp, abort_other_plans);
1616         return thread_plan_sp;
1617     }
1618     else
1619     {
1620         return ThreadPlanSP();
1621     }
1622 }
1623 
1624 ThreadPlanSP
1625 Thread::QueueThreadPlanForStepThrough (StackID &return_stack_id, bool abort_other_plans, bool stop_other_threads)
1626 {
1627     ThreadPlanSP thread_plan_sp(new ThreadPlanStepThrough (*this, return_stack_id, stop_other_threads));
1628     if (!thread_plan_sp || !thread_plan_sp->ValidatePlan (NULL))
1629         return ThreadPlanSP();
1630 
1631     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1632     return thread_plan_sp;
1633 }
1634 
1635 ThreadPlanSP
1636 Thread::QueueThreadPlanForRunToAddress (bool abort_other_plans,
1637                                         Address &target_addr,
1638                                         bool stop_other_threads)
1639 {
1640     ThreadPlanSP thread_plan_sp (new ThreadPlanRunToAddress (*this, target_addr, stop_other_threads));
1641     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1642     return thread_plan_sp;
1643 }
1644 
1645 ThreadPlanSP
1646 Thread::QueueThreadPlanForStepUntil (bool abort_other_plans,
1647                                      lldb::addr_t *address_list,
1648                                      size_t num_addresses,
1649                                      bool stop_other_threads,
1650                                      uint32_t frame_idx)
1651 {
1652     ThreadPlanSP thread_plan_sp (new ThreadPlanStepUntil (*this, address_list, num_addresses, stop_other_threads, frame_idx));
1653     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1654     return thread_plan_sp;
1655 
1656 }
1657 
1658 lldb::ThreadPlanSP
1659 Thread::QueueThreadPlanForStepScripted (bool abort_other_plans,
1660                                         const char *class_name,
1661                                         bool stop_other_threads)
1662 {
1663     ThreadPlanSP thread_plan_sp (new ThreadPlanPython (*this, class_name));
1664     QueueThreadPlan (thread_plan_sp, abort_other_plans);
1665     // This seems a little funny, but I don't want to have to split up the constructor and the
1666     // DidPush in the scripted plan, that seems annoying.
1667     // That means the constructor has to be in DidPush.
1668     // So I have to validate the plan AFTER pushing it, and then take it off again...
1669     if (!thread_plan_sp->ValidatePlan(nullptr))
1670     {
1671         DiscardThreadPlansUpToPlan(thread_plan_sp);
1672         return ThreadPlanSP();
1673     }
1674     else
1675         return thread_plan_sp;
1676 }
1677 
1678 uint32_t
1679 Thread::GetIndexID () const
1680 {
1681     return m_index_id;
1682 }
1683 
1684 static void
1685 PrintPlanElement (Stream *s, const ThreadPlanSP &plan, lldb::DescriptionLevel desc_level, int32_t elem_idx)
1686 {
1687         s->IndentMore();
1688         s->Indent();
1689         s->Printf ("Element %d: ", elem_idx);
1690         plan->GetDescription (s, desc_level);
1691         s->EOL();
1692         s->IndentLess();
1693 }
1694 
1695 static void
1696 PrintPlanStack (Stream *s, const std::vector<lldb::ThreadPlanSP> &plan_stack, lldb::DescriptionLevel desc_level, bool include_internal)
1697 {
1698     int32_t print_idx = 0;
1699     for (ThreadPlanSP plan_sp : plan_stack)
1700     {
1701         if (include_internal || !plan_sp->GetPrivate())
1702         {
1703             PrintPlanElement (s, plan_sp, desc_level, print_idx++);
1704         }
1705     }
1706 }
1707 
1708 void
1709 Thread::DumpThreadPlans (Stream *s,
1710                          lldb::DescriptionLevel desc_level,
1711                          bool include_internal,
1712                          bool ignore_boring_threads) const
1713 {
1714     uint32_t stack_size;
1715 
1716     if (ignore_boring_threads)
1717     {
1718         uint32_t stack_size = m_plan_stack.size();
1719         uint32_t completed_stack_size = m_completed_plan_stack.size();
1720         uint32_t discarded_stack_size = m_discarded_plan_stack.size();
1721         if (stack_size == 1 && completed_stack_size == 0 && discarded_stack_size == 0)
1722         {
1723             s->Printf ("thread #%u: tid = 0x%4.4" PRIx64 "\n", GetIndexID(), GetID());
1724             s->IndentMore();
1725             s->Indent();
1726             s->Printf("No active thread plans\n");
1727             s->IndentLess();
1728             return;
1729         }
1730     }
1731 
1732     s->Indent();
1733     s->Printf ("thread #%u: tid = 0x%4.4" PRIx64 ":\n", GetIndexID(), GetID());
1734     s->IndentMore();
1735     s->Indent();
1736     s->Printf ("Active plan stack:\n");
1737     PrintPlanStack (s, m_plan_stack, desc_level, include_internal);
1738 
1739     stack_size = m_completed_plan_stack.size();
1740     if (stack_size > 0)
1741     {
1742         s->Indent();
1743         s->Printf ("Completed Plan Stack:\n");
1744         PrintPlanStack (s, m_completed_plan_stack, desc_level, include_internal);
1745     }
1746 
1747     stack_size = m_discarded_plan_stack.size();
1748     if (stack_size > 0)
1749     {
1750         s->Indent();
1751         s->Printf ("Discarded Plan Stack:\n");
1752         PrintPlanStack (s, m_discarded_plan_stack, desc_level, include_internal);
1753     }
1754 
1755     s->IndentLess();
1756 }
1757 
1758 TargetSP
1759 Thread::CalculateTarget ()
1760 {
1761     TargetSP target_sp;
1762     ProcessSP process_sp(GetProcess());
1763     if (process_sp)
1764         target_sp = process_sp->CalculateTarget();
1765     return target_sp;
1766 
1767 }
1768 
1769 ProcessSP
1770 Thread::CalculateProcess ()
1771 {
1772     return GetProcess();
1773 }
1774 
1775 ThreadSP
1776 Thread::CalculateThread ()
1777 {
1778     return shared_from_this();
1779 }
1780 
1781 StackFrameSP
1782 Thread::CalculateStackFrame ()
1783 {
1784     return StackFrameSP();
1785 }
1786 
1787 void
1788 Thread::CalculateExecutionContext (ExecutionContext &exe_ctx)
1789 {
1790     exe_ctx.SetContext (shared_from_this());
1791 }
1792 
1793 StackFrameListSP
1794 Thread::GetStackFrameList ()
1795 {
1796     StackFrameListSP frame_list_sp;
1797     Mutex::Locker locker(m_frame_mutex);
1798     if (m_curr_frames_sp)
1799     {
1800         frame_list_sp = m_curr_frames_sp;
1801     }
1802     else
1803     {
1804         frame_list_sp.reset(new StackFrameList (*this, m_prev_frames_sp, true));
1805         m_curr_frames_sp = frame_list_sp;
1806     }
1807     return frame_list_sp;
1808 }
1809 
1810 void
1811 Thread::ClearStackFrames ()
1812 {
1813     Mutex::Locker locker(m_frame_mutex);
1814 
1815     Unwind *unwinder = GetUnwinder ();
1816     if (unwinder)
1817         unwinder->Clear();
1818 
1819     // Only store away the old "reference" StackFrameList if we got all its frames:
1820     // FIXME: At some point we can try to splice in the frames we have fetched into
1821     // the new frame as we make it, but let's not try that now.
1822     if (m_curr_frames_sp && m_curr_frames_sp->GetAllFramesFetched())
1823         m_prev_frames_sp.swap (m_curr_frames_sp);
1824     m_curr_frames_sp.reset();
1825 
1826     m_extended_info.reset();
1827     m_extended_info_fetched = false;
1828 }
1829 
1830 lldb::StackFrameSP
1831 Thread::GetFrameWithConcreteFrameIndex (uint32_t unwind_idx)
1832 {
1833     return GetStackFrameList()->GetFrameWithConcreteFrameIndex (unwind_idx);
1834 }
1835 
1836 Error
1837 Thread::ReturnFromFrameWithIndex (uint32_t frame_idx, lldb::ValueObjectSP return_value_sp, bool broadcast)
1838 {
1839     StackFrameSP frame_sp = GetStackFrameAtIndex (frame_idx);
1840     Error return_error;
1841 
1842     if (!frame_sp)
1843     {
1844         return_error.SetErrorStringWithFormat("Could not find frame with index %d in thread 0x%" PRIx64 ".", frame_idx, GetID());
1845     }
1846 
1847     return ReturnFromFrame(frame_sp, return_value_sp, broadcast);
1848 }
1849 
1850 Error
1851 Thread::ReturnFromFrame (lldb::StackFrameSP frame_sp, lldb::ValueObjectSP return_value_sp, bool broadcast)
1852 {
1853     Error return_error;
1854 
1855     if (!frame_sp)
1856     {
1857         return_error.SetErrorString("Can't return to a null frame.");
1858         return return_error;
1859     }
1860 
1861     Thread *thread = frame_sp->GetThread().get();
1862     uint32_t older_frame_idx = frame_sp->GetFrameIndex() + 1;
1863     StackFrameSP older_frame_sp = thread->GetStackFrameAtIndex(older_frame_idx);
1864     if (!older_frame_sp)
1865     {
1866         return_error.SetErrorString("No older frame to return to.");
1867         return return_error;
1868     }
1869 
1870     if (return_value_sp)
1871     {
1872         lldb::ABISP abi = thread->GetProcess()->GetABI();
1873         if (!abi)
1874         {
1875             return_error.SetErrorString("Could not find ABI to set return value.");
1876             return return_error;
1877         }
1878         SymbolContext sc = frame_sp->GetSymbolContext(eSymbolContextFunction);
1879 
1880         // FIXME: ValueObject::Cast doesn't currently work correctly, at least not for scalars.
1881         // Turn that back on when that works.
1882         if (/* DISABLES CODE */ (0) && sc.function != NULL)
1883         {
1884             Type *function_type = sc.function->GetType();
1885             if (function_type)
1886             {
1887                 CompilerType return_type = sc.function->GetCompilerType().GetFunctionReturnType();
1888                 if (return_type)
1889                 {
1890                     StreamString s;
1891                     return_type.DumpTypeDescription(&s);
1892                     ValueObjectSP cast_value_sp = return_value_sp->Cast(return_type);
1893                     if (cast_value_sp)
1894                     {
1895                         cast_value_sp->SetFormat(eFormatHex);
1896                         return_value_sp = cast_value_sp;
1897                     }
1898                 }
1899             }
1900         }
1901 
1902         return_error = abi->SetReturnValueObject(older_frame_sp, return_value_sp);
1903         if (!return_error.Success())
1904             return return_error;
1905     }
1906 
1907     // Now write the return registers for the chosen frame:
1908     // Note, we can't use ReadAllRegisterValues->WriteAllRegisterValues, since the read & write
1909     // cook their data
1910 
1911     StackFrameSP youngest_frame_sp = thread->GetStackFrameAtIndex(0);
1912     if (youngest_frame_sp)
1913     {
1914         lldb::RegisterContextSP reg_ctx_sp (youngest_frame_sp->GetRegisterContext());
1915         if (reg_ctx_sp)
1916         {
1917             bool copy_success = reg_ctx_sp->CopyFromRegisterContext(older_frame_sp->GetRegisterContext());
1918             if (copy_success)
1919             {
1920                 thread->DiscardThreadPlans(true);
1921                 thread->ClearStackFrames();
1922                 if (broadcast && EventTypeHasListeners(eBroadcastBitStackChanged))
1923                     BroadcastEvent(eBroadcastBitStackChanged, new ThreadEventData (this->shared_from_this()));
1924             }
1925             else
1926             {
1927                 return_error.SetErrorString("Could not reset register values.");
1928             }
1929         }
1930         else
1931         {
1932             return_error.SetErrorString("Frame has no register context.");
1933         }
1934     }
1935     else
1936     {
1937         return_error.SetErrorString("Returned past top frame.");
1938     }
1939     return return_error;
1940 }
1941 
1942 static void DumpAddressList (Stream &s, const std::vector<Address> &list, ExecutionContextScope *exe_scope)
1943 {
1944     for (size_t n=0;n<list.size();n++)
1945     {
1946         s << "\t";
1947         list[n].Dump (&s, exe_scope, Address::DumpStyleResolvedDescription, Address::DumpStyleSectionNameOffset);
1948         s << "\n";
1949     }
1950 }
1951 
1952 Error
1953 Thread::JumpToLine (const FileSpec &file, uint32_t line, bool can_leave_function, std::string *warnings)
1954 {
1955     ExecutionContext exe_ctx (GetStackFrameAtIndex(0));
1956     Target *target = exe_ctx.GetTargetPtr();
1957     TargetSP target_sp = exe_ctx.GetTargetSP();
1958     RegisterContext *reg_ctx = exe_ctx.GetRegisterContext();
1959     StackFrame *frame = exe_ctx.GetFramePtr();
1960     const SymbolContext &sc = frame->GetSymbolContext(eSymbolContextFunction);
1961 
1962     // Find candidate locations.
1963     std::vector<Address> candidates, within_function, outside_function;
1964     target->GetImages().FindAddressesForLine (target_sp, file, line, sc.function, within_function, outside_function);
1965 
1966     // If possible, we try and stay within the current function.
1967     // Within a function, we accept multiple locations (optimized code may do this,
1968     // there's no solution here so we do the best we can).
1969     // However if we're trying to leave the function, we don't know how to pick the
1970     // right location, so if there's more than one then we bail.
1971     if (!within_function.empty())
1972         candidates = within_function;
1973     else if (outside_function.size() == 1 && can_leave_function)
1974         candidates = outside_function;
1975 
1976     // Check if we got anything.
1977     if (candidates.empty())
1978     {
1979         if (outside_function.empty())
1980         {
1981             return Error("Cannot locate an address for %s:%i.",
1982                          file.GetFilename().AsCString(), line);
1983         }
1984         else if (outside_function.size() == 1)
1985         {
1986             return Error("%s:%i is outside the current function.",
1987                          file.GetFilename().AsCString(), line);
1988         }
1989         else
1990         {
1991             StreamString sstr;
1992             DumpAddressList(sstr, outside_function, target);
1993             return Error("%s:%i has multiple candidate locations:\n%s",
1994                          file.GetFilename().AsCString(), line, sstr.GetString().c_str());
1995         }
1996     }
1997 
1998     // Accept the first location, warn about any others.
1999     Address dest = candidates[0];
2000     if (warnings && candidates.size() > 1)
2001     {
2002         StreamString sstr;
2003         sstr.Printf("%s:%i appears multiple times in this function, selecting the first location:\n",
2004                      file.GetFilename().AsCString(), line);
2005         DumpAddressList(sstr, candidates, target);
2006         *warnings = sstr.GetString();
2007     }
2008 
2009     if (!reg_ctx->SetPC (dest))
2010         return Error("Cannot change PC to target address.");
2011 
2012     return Error();
2013 }
2014 
2015 void
2016 Thread::DumpUsingSettingsFormat (Stream &strm, uint32_t frame_idx)
2017 {
2018     ExecutionContext exe_ctx (shared_from_this());
2019     Process *process = exe_ctx.GetProcessPtr();
2020     if (process == NULL)
2021         return;
2022 
2023     StackFrameSP frame_sp;
2024     SymbolContext frame_sc;
2025     if (frame_idx != LLDB_INVALID_FRAME_ID)
2026     {
2027         frame_sp = GetStackFrameAtIndex (frame_idx);
2028         if (frame_sp)
2029         {
2030             exe_ctx.SetFrameSP(frame_sp);
2031             frame_sc = frame_sp->GetSymbolContext(eSymbolContextEverything);
2032         }
2033     }
2034 
2035     const FormatEntity::Entry *thread_format = exe_ctx.GetTargetRef().GetDebugger().GetThreadFormat();
2036     assert (thread_format);
2037 
2038     FormatEntity::Format(*thread_format,
2039                          strm,
2040                          frame_sp ? &frame_sc : NULL,
2041                          &exe_ctx,
2042                          NULL,
2043                          NULL,
2044                          false,
2045                          false);
2046 }
2047 
2048 void
2049 Thread::SettingsInitialize ()
2050 {
2051 }
2052 
2053 void
2054 Thread::SettingsTerminate ()
2055 {
2056 }
2057 
2058 lldb::addr_t
2059 Thread::GetThreadPointer ()
2060 {
2061     return LLDB_INVALID_ADDRESS;
2062 }
2063 
2064 addr_t
2065 Thread::GetThreadLocalData (const ModuleSP module)
2066 {
2067     // The default implementation is to ask the dynamic loader for it.
2068     // This can be overridden for specific platforms.
2069     DynamicLoader *loader = GetProcess()->GetDynamicLoader();
2070     if (loader)
2071         return loader->GetThreadLocalData (module, shared_from_this());
2072     else
2073         return LLDB_INVALID_ADDRESS;
2074 }
2075 
2076 bool
2077 Thread::SafeToCallFunctions ()
2078 {
2079     Process *process = GetProcess().get();
2080     if (process)
2081     {
2082         SystemRuntime *runtime = process->GetSystemRuntime ();
2083         if (runtime)
2084         {
2085             return runtime->SafeToCallFunctionsOnThisThread (shared_from_this());
2086         }
2087     }
2088     return true;
2089 }
2090 
2091 lldb::StackFrameSP
2092 Thread::GetStackFrameSPForStackFramePtr (StackFrame *stack_frame_ptr)
2093 {
2094     return GetStackFrameList()->GetStackFrameSPForStackFramePtr (stack_frame_ptr);
2095 }
2096 
2097 const char *
2098 Thread::StopReasonAsCString (lldb::StopReason reason)
2099 {
2100     switch (reason)
2101     {
2102     case eStopReasonInvalid:       return "invalid";
2103     case eStopReasonNone:          return "none";
2104     case eStopReasonTrace:         return "trace";
2105     case eStopReasonBreakpoint:    return "breakpoint";
2106     case eStopReasonWatchpoint:    return "watchpoint";
2107     case eStopReasonSignal:        return "signal";
2108     case eStopReasonException:     return "exception";
2109     case eStopReasonExec:          return "exec";
2110     case eStopReasonPlanComplete:  return "plan complete";
2111     case eStopReasonThreadExiting: return "thread exiting";
2112     case eStopReasonInstrumentation: return "instrumentation break";
2113     }
2114 
2115     static char unknown_state_string[64];
2116     snprintf(unknown_state_string, sizeof (unknown_state_string), "StopReason = %i", reason);
2117     return unknown_state_string;
2118 }
2119 
2120 const char *
2121 Thread::RunModeAsCString (lldb::RunMode mode)
2122 {
2123     switch (mode)
2124     {
2125     case eOnlyThisThread:     return "only this thread";
2126     case eAllThreads:         return "all threads";
2127     case eOnlyDuringStepping: return "only during stepping";
2128     }
2129 
2130     static char unknown_state_string[64];
2131     snprintf(unknown_state_string, sizeof (unknown_state_string), "RunMode = %i", mode);
2132     return unknown_state_string;
2133 }
2134 
2135 size_t
2136 Thread::GetStatus (Stream &strm, uint32_t start_frame, uint32_t num_frames, uint32_t num_frames_with_source)
2137 {
2138     ExecutionContext exe_ctx (shared_from_this());
2139     Target *target = exe_ctx.GetTargetPtr();
2140     Process *process = exe_ctx.GetProcessPtr();
2141     size_t num_frames_shown = 0;
2142     strm.Indent();
2143     bool is_selected = false;
2144     if (process)
2145     {
2146         if (process->GetThreadList().GetSelectedThread().get() == this)
2147             is_selected = true;
2148     }
2149     strm.Printf("%c ", is_selected ? '*' : ' ');
2150     if (target && target->GetDebugger().GetUseExternalEditor())
2151     {
2152         StackFrameSP frame_sp = GetStackFrameAtIndex(start_frame);
2153         if (frame_sp)
2154         {
2155             SymbolContext frame_sc(frame_sp->GetSymbolContext (eSymbolContextLineEntry));
2156             if (frame_sc.line_entry.line != 0 && frame_sc.line_entry.file)
2157             {
2158                 Host::OpenFileInExternalEditor (frame_sc.line_entry.file, frame_sc.line_entry.line);
2159             }
2160         }
2161     }
2162 
2163     DumpUsingSettingsFormat (strm, start_frame);
2164 
2165     if (num_frames > 0)
2166     {
2167         strm.IndentMore();
2168 
2169         const bool show_frame_info = true;
2170 
2171         const char *selected_frame_marker = NULL;
2172         if (num_frames == 1 || (GetID() != GetProcess()->GetThreadList().GetSelectedThread()->GetID()))
2173             strm.IndentMore ();
2174         else
2175             selected_frame_marker = "* ";
2176 
2177         num_frames_shown = GetStackFrameList ()->GetStatus (strm,
2178                                                             start_frame,
2179                                                             num_frames,
2180                                                             show_frame_info,
2181                                                             num_frames_with_source,
2182                                                             selected_frame_marker);
2183         if (num_frames == 1)
2184             strm.IndentLess();
2185         strm.IndentLess();
2186     }
2187     return num_frames_shown;
2188 }
2189 
2190 bool
2191 Thread::GetDescription (Stream &strm, lldb::DescriptionLevel level, bool print_json_thread, bool print_json_stopinfo)
2192 {
2193     DumpUsingSettingsFormat (strm, 0);
2194     strm.Printf("\n");
2195 
2196     StructuredData::ObjectSP thread_info = GetExtendedInfo();
2197 
2198     if (print_json_thread || print_json_stopinfo)
2199     {
2200         if (thread_info && print_json_thread)
2201         {
2202             thread_info->Dump (strm);
2203             strm.Printf("\n");
2204         }
2205 
2206         if (print_json_stopinfo && m_stop_info_sp)
2207         {
2208             StructuredData::ObjectSP stop_info = m_stop_info_sp->GetExtendedInfo();
2209             if (stop_info)
2210             {
2211                 stop_info->Dump (strm);
2212                 strm.Printf("\n");
2213             }
2214         }
2215 
2216         return true;
2217     }
2218 
2219     if (thread_info)
2220     {
2221         StructuredData::ObjectSP activity = thread_info->GetObjectForDotSeparatedPath("activity");
2222         StructuredData::ObjectSP breadcrumb = thread_info->GetObjectForDotSeparatedPath("breadcrumb");
2223         StructuredData::ObjectSP messages = thread_info->GetObjectForDotSeparatedPath("trace_messages");
2224 
2225         bool printed_activity = false;
2226         if (activity && activity->GetType() == StructuredData::Type::eTypeDictionary)
2227         {
2228             StructuredData::Dictionary *activity_dict = activity->GetAsDictionary();
2229             StructuredData::ObjectSP id = activity_dict->GetValueForKey("id");
2230             StructuredData::ObjectSP name = activity_dict->GetValueForKey("name");
2231             if (name && name->GetType() == StructuredData::Type::eTypeString
2232                 && id && id->GetType() == StructuredData::Type::eTypeInteger)
2233             {
2234                 strm.Printf("  Activity '%s', 0x%" PRIx64 "\n", name->GetAsString()->GetValue().c_str(), id->GetAsInteger()->GetValue());
2235             }
2236             printed_activity = true;
2237         }
2238         bool printed_breadcrumb = false;
2239         if (breadcrumb && breadcrumb->GetType() == StructuredData::Type::eTypeDictionary)
2240         {
2241             if (printed_activity)
2242                 strm.Printf ("\n");
2243             StructuredData::Dictionary *breadcrumb_dict = breadcrumb->GetAsDictionary();
2244             StructuredData::ObjectSP breadcrumb_text = breadcrumb_dict->GetValueForKey ("name");
2245             if (breadcrumb_text && breadcrumb_text->GetType() == StructuredData::Type::eTypeString)
2246             {
2247                 strm.Printf ("  Current Breadcrumb: %s\n", breadcrumb_text->GetAsString()->GetValue().c_str());
2248             }
2249             printed_breadcrumb = true;
2250         }
2251         if (messages && messages->GetType() == StructuredData::Type::eTypeArray)
2252         {
2253             if (printed_breadcrumb)
2254                 strm.Printf("\n");
2255             StructuredData::Array *messages_array = messages->GetAsArray();
2256             const size_t msg_count = messages_array->GetSize();
2257             if (msg_count > 0)
2258             {
2259                 strm.Printf ("  %zu trace messages:\n", msg_count);
2260                 for (size_t i = 0; i < msg_count; i++)
2261                 {
2262                     StructuredData::ObjectSP message = messages_array->GetItemAtIndex(i);
2263                     if (message && message->GetType() == StructuredData::Type::eTypeDictionary)
2264                     {
2265                         StructuredData::Dictionary *message_dict = message->GetAsDictionary();
2266                         StructuredData::ObjectSP message_text = message_dict->GetValueForKey ("message");
2267                         if (message_text && message_text->GetType() == StructuredData::Type::eTypeString)
2268                         {
2269                             strm.Printf ("    %s\n", message_text->GetAsString()->GetValue().c_str());
2270                         }
2271                     }
2272                 }
2273             }
2274         }
2275     }
2276 
2277     return true;
2278 }
2279 
2280 size_t
2281 Thread::GetStackFrameStatus (Stream& strm,
2282                              uint32_t first_frame,
2283                              uint32_t num_frames,
2284                              bool show_frame_info,
2285                              uint32_t num_frames_with_source)
2286 {
2287     return GetStackFrameList()->GetStatus (strm,
2288                                            first_frame,
2289                                            num_frames,
2290                                            show_frame_info,
2291                                            num_frames_with_source);
2292 }
2293 
2294 Unwind *
2295 Thread::GetUnwinder ()
2296 {
2297     if (m_unwinder_ap.get() == NULL)
2298     {
2299         const ArchSpec target_arch (CalculateTarget()->GetArchitecture ());
2300         const llvm::Triple::ArchType machine = target_arch.GetMachine();
2301         switch (machine)
2302         {
2303             case llvm::Triple::x86_64:
2304             case llvm::Triple::x86:
2305             case llvm::Triple::arm:
2306             case llvm::Triple::aarch64:
2307             case llvm::Triple::thumb:
2308             case llvm::Triple::mips:
2309             case llvm::Triple::mipsel:
2310             case llvm::Triple::mips64:
2311             case llvm::Triple::mips64el:
2312             case llvm::Triple::ppc:
2313             case llvm::Triple::ppc64:
2314             case llvm::Triple::hexagon:
2315                 m_unwinder_ap.reset (new UnwindLLDB (*this));
2316                 break;
2317 
2318             default:
2319                 if (target_arch.GetTriple().getVendor() == llvm::Triple::Apple)
2320                     m_unwinder_ap.reset (new UnwindMacOSXFrameBackchain (*this));
2321                 break;
2322         }
2323     }
2324     return m_unwinder_ap.get();
2325 }
2326 
2327 void
2328 Thread::Flush ()
2329 {
2330     ClearStackFrames ();
2331     m_reg_context_sp.reset();
2332 }
2333 
2334 bool
2335 Thread::IsStillAtLastBreakpointHit ()
2336 {
2337     // If we are currently stopped at a breakpoint, always return that stopinfo and don't reset it.
2338     // This allows threads to maintain their breakpoint stopinfo, such as when thread-stepping in
2339     // multithreaded programs.
2340     if (m_stop_info_sp) {
2341         StopReason stop_reason = m_stop_info_sp->GetStopReason();
2342         if (stop_reason == lldb::eStopReasonBreakpoint) {
2343             uint64_t value = m_stop_info_sp->GetValue();
2344             lldb::RegisterContextSP reg_ctx_sp (GetRegisterContext());
2345             if (reg_ctx_sp)
2346             {
2347                 lldb::addr_t pc = reg_ctx_sp->GetPC();
2348                 BreakpointSiteSP bp_site_sp = GetProcess()->GetBreakpointSiteList().FindByAddress(pc);
2349                 if (bp_site_sp &&
2350                     static_cast<break_id_t>(value) == bp_site_sp->GetID())
2351                     return true;
2352             }
2353         }
2354     }
2355     return false;
2356 }
2357 
2358 Error
2359 Thread::StepIn (bool source_step,
2360                 LazyBool step_in_avoids_code_without_debug_info,
2361                 LazyBool step_out_avoids_code_without_debug_info)
2362 
2363 {
2364     Error error;
2365     Process *process = GetProcess().get();
2366     if (StateIsStoppedState (process->GetState(), true))
2367     {
2368         StackFrameSP frame_sp = GetStackFrameAtIndex (0);
2369         ThreadPlanSP new_plan_sp;
2370         const lldb::RunMode run_mode = eOnlyThisThread;
2371         const bool abort_other_plans = false;
2372 
2373         if (source_step && frame_sp && frame_sp->HasDebugInformation ())
2374         {
2375             SymbolContext sc(frame_sp->GetSymbolContext(eSymbolContextEverything));
2376             new_plan_sp = QueueThreadPlanForStepInRange (abort_other_plans,
2377                                                          sc.line_entry.range,
2378                                                          sc,
2379                                                          NULL,
2380                                                          run_mode,
2381                                                          step_in_avoids_code_without_debug_info,
2382                                                          step_out_avoids_code_without_debug_info);
2383         }
2384         else
2385         {
2386             new_plan_sp = QueueThreadPlanForStepSingleInstruction (false,
2387                                                                    abort_other_plans,
2388                                                                    run_mode);
2389         }
2390 
2391         new_plan_sp->SetIsMasterPlan(true);
2392         new_plan_sp->SetOkayToDiscard(false);
2393 
2394         // Why do we need to set the current thread by ID here???
2395         process->GetThreadList().SetSelectedThreadByID (GetID());
2396         error = process->Resume();
2397     }
2398     else
2399     {
2400         error.SetErrorString("process not stopped");
2401     }
2402     return error;
2403 }
2404 
2405 Error
2406 Thread::StepOver (bool source_step,
2407                 LazyBool step_out_avoids_code_without_debug_info)
2408 {
2409     Error error;
2410     Process *process = GetProcess().get();
2411     if (StateIsStoppedState (process->GetState(), true))
2412     {
2413         StackFrameSP frame_sp = GetStackFrameAtIndex (0);
2414         ThreadPlanSP new_plan_sp;
2415 
2416         const lldb::RunMode run_mode = eOnlyThisThread;
2417         const bool abort_other_plans = false;
2418 
2419         if (source_step && frame_sp && frame_sp->HasDebugInformation ())
2420         {
2421             SymbolContext sc(frame_sp->GetSymbolContext(eSymbolContextEverything));
2422             new_plan_sp = QueueThreadPlanForStepOverRange (abort_other_plans,
2423                                                            sc.line_entry.range,
2424                                                            sc,
2425                                                            run_mode,
2426                                                            step_out_avoids_code_without_debug_info);
2427         }
2428         else
2429         {
2430             new_plan_sp = QueueThreadPlanForStepSingleInstruction (true,
2431                                                                    abort_other_plans,
2432                                                                    run_mode);
2433         }
2434 
2435         new_plan_sp->SetIsMasterPlan(true);
2436         new_plan_sp->SetOkayToDiscard(false);
2437 
2438         // Why do we need to set the current thread by ID here???
2439         process->GetThreadList().SetSelectedThreadByID (GetID());
2440         error = process->Resume();
2441     }
2442     else
2443     {
2444         error.SetErrorString("process not stopped");
2445     }
2446     return error;
2447 }
2448 
2449 Error
2450 Thread::StepOut ()
2451 {
2452     Error error;
2453     Process *process = GetProcess().get();
2454     if (StateIsStoppedState (process->GetState(), true))
2455     {
2456         const bool first_instruction = false;
2457         const bool stop_other_threads = false;
2458         const bool abort_other_plans = false;
2459 
2460         ThreadPlanSP new_plan_sp(QueueThreadPlanForStepOut (abort_other_plans,
2461                                                             NULL,
2462                                                             first_instruction,
2463                                                             stop_other_threads,
2464                                                             eVoteYes,
2465                                                             eVoteNoOpinion,
2466                                                             0));
2467 
2468         new_plan_sp->SetIsMasterPlan(true);
2469         new_plan_sp->SetOkayToDiscard(false);
2470 
2471         // Why do we need to set the current thread by ID here???
2472         process->GetThreadList().SetSelectedThreadByID (GetID());
2473         error = process->Resume();
2474     }
2475     else
2476     {
2477         error.SetErrorString("process not stopped");
2478     }
2479     return error;
2480 }
2481