xref: /llvm-project/lldb/source/Target/Thread.cpp (revision 22561cfb443267905d4190f0e2a738e6b412457f)
1 //===-- Thread.cpp --------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "lldb/Target/Thread.h"
10 #include "lldb/Breakpoint/BreakpointLocation.h"
11 #include "lldb/Core/Debugger.h"
12 #include "lldb/Core/FormatEntity.h"
13 #include "lldb/Core/Module.h"
14 #include "lldb/Core/StructuredDataImpl.h"
15 #include "lldb/Host/Host.h"
16 #include "lldb/Interpreter/OptionValueFileSpecList.h"
17 #include "lldb/Interpreter/OptionValueProperties.h"
18 #include "lldb/Interpreter/Property.h"
19 #include "lldb/Symbol/Function.h"
20 #include "lldb/Target/ABI.h"
21 #include "lldb/Target/DynamicLoader.h"
22 #include "lldb/Target/ExecutionContext.h"
23 #include "lldb/Target/LanguageRuntime.h"
24 #include "lldb/Target/Process.h"
25 #include "lldb/Target/RegisterContext.h"
26 #include "lldb/Target/ScriptedThreadPlan.h"
27 #include "lldb/Target/StackFrameRecognizer.h"
28 #include "lldb/Target/StopInfo.h"
29 #include "lldb/Target/SystemRuntime.h"
30 #include "lldb/Target/Target.h"
31 #include "lldb/Target/ThreadPlan.h"
32 #include "lldb/Target/ThreadPlanBase.h"
33 #include "lldb/Target/ThreadPlanCallFunction.h"
34 #include "lldb/Target/ThreadPlanRunToAddress.h"
35 #include "lldb/Target/ThreadPlanStack.h"
36 #include "lldb/Target/ThreadPlanStepInRange.h"
37 #include "lldb/Target/ThreadPlanStepInstruction.h"
38 #include "lldb/Target/ThreadPlanStepOut.h"
39 #include "lldb/Target/ThreadPlanStepOverBreakpoint.h"
40 #include "lldb/Target/ThreadPlanStepOverRange.h"
41 #include "lldb/Target/ThreadPlanStepThrough.h"
42 #include "lldb/Target/ThreadPlanStepUntil.h"
43 #include "lldb/Target/ThreadSpec.h"
44 #include "lldb/Target/UnwindLLDB.h"
45 #include "lldb/Utility/LLDBLog.h"
46 #include "lldb/Utility/Log.h"
47 #include "lldb/Utility/RegularExpression.h"
48 #include "lldb/Utility/State.h"
49 #include "lldb/Utility/Stream.h"
50 #include "lldb/Utility/StreamString.h"
51 #include "lldb/ValueObject/ValueObject.h"
52 #include "lldb/ValueObject/ValueObjectConstResult.h"
53 #include "lldb/lldb-enumerations.h"
54 
55 #include <memory>
56 #include <optional>
57 
58 using namespace lldb;
59 using namespace lldb_private;
60 
61 ThreadProperties &Thread::GetGlobalProperties() {
62   // NOTE: intentional leak so we don't crash if global destructor chain gets
63   // called as other threads still use the result of this function
64   static ThreadProperties *g_settings_ptr = new ThreadProperties(true);
65   return *g_settings_ptr;
66 }
67 
68 #define LLDB_PROPERTIES_thread
69 #include "TargetProperties.inc"
70 
71 enum {
72 #define LLDB_PROPERTIES_thread
73 #include "TargetPropertiesEnum.inc"
74 };
75 
76 class ThreadOptionValueProperties
77     : public Cloneable<ThreadOptionValueProperties, OptionValueProperties> {
78 public:
79   ThreadOptionValueProperties(llvm::StringRef name) : Cloneable(name) {}
80 
81   const Property *
82   GetPropertyAtIndex(size_t idx,
83                      const ExecutionContext *exe_ctx) const override {
84     // When getting the value for a key from the thread options, we will always
85     // try and grab the setting from the current thread if there is one. Else
86     // we just use the one from this instance.
87     if (exe_ctx) {
88       Thread *thread = exe_ctx->GetThreadPtr();
89       if (thread) {
90         ThreadOptionValueProperties *instance_properties =
91             static_cast<ThreadOptionValueProperties *>(
92                 thread->GetValueProperties().get());
93         if (this != instance_properties)
94           return instance_properties->ProtectedGetPropertyAtIndex(idx);
95       }
96     }
97     return ProtectedGetPropertyAtIndex(idx);
98   }
99 };
100 
101 ThreadProperties::ThreadProperties(bool is_global) : Properties() {
102   if (is_global) {
103     m_collection_sp = std::make_shared<ThreadOptionValueProperties>("thread");
104     m_collection_sp->Initialize(g_thread_properties);
105   } else
106     m_collection_sp =
107         OptionValueProperties::CreateLocalCopy(Thread::GetGlobalProperties());
108 }
109 
110 ThreadProperties::~ThreadProperties() = default;
111 
112 const RegularExpression *ThreadProperties::GetSymbolsToAvoidRegexp() {
113   const uint32_t idx = ePropertyStepAvoidRegex;
114   return GetPropertyAtIndexAs<const RegularExpression *>(idx);
115 }
116 
117 FileSpecList ThreadProperties::GetLibrariesToAvoid() const {
118   const uint32_t idx = ePropertyStepAvoidLibraries;
119   return GetPropertyAtIndexAs<FileSpecList>(idx, {});
120 }
121 
122 bool ThreadProperties::GetTraceEnabledState() const {
123   const uint32_t idx = ePropertyEnableThreadTrace;
124   return GetPropertyAtIndexAs<bool>(
125       idx, g_thread_properties[idx].default_uint_value != 0);
126 }
127 
128 bool ThreadProperties::GetStepInAvoidsNoDebug() const {
129   const uint32_t idx = ePropertyStepInAvoidsNoDebug;
130   return GetPropertyAtIndexAs<bool>(
131       idx, g_thread_properties[idx].default_uint_value != 0);
132 }
133 
134 bool ThreadProperties::GetStepOutAvoidsNoDebug() const {
135   const uint32_t idx = ePropertyStepOutAvoidsNoDebug;
136   return GetPropertyAtIndexAs<bool>(
137       idx, g_thread_properties[idx].default_uint_value != 0);
138 }
139 
140 uint64_t ThreadProperties::GetMaxBacktraceDepth() const {
141   const uint32_t idx = ePropertyMaxBacktraceDepth;
142   return GetPropertyAtIndexAs<uint64_t>(
143       idx, g_thread_properties[idx].default_uint_value);
144 }
145 
146 uint64_t ThreadProperties::GetSingleThreadPlanTimeout() const {
147   const uint32_t idx = ePropertySingleThreadPlanTimeout;
148   return GetPropertyAtIndexAs<uint64_t>(
149       idx, g_thread_properties[idx].default_uint_value);
150 }
151 
152 // Thread Event Data
153 
154 llvm::StringRef Thread::ThreadEventData::GetFlavorString() {
155   return "Thread::ThreadEventData";
156 }
157 
158 Thread::ThreadEventData::ThreadEventData(const lldb::ThreadSP thread_sp)
159     : m_thread_sp(thread_sp), m_stack_id() {}
160 
161 Thread::ThreadEventData::ThreadEventData(const lldb::ThreadSP thread_sp,
162                                          const StackID &stack_id)
163     : m_thread_sp(thread_sp), m_stack_id(stack_id) {}
164 
165 Thread::ThreadEventData::ThreadEventData() : m_thread_sp(), m_stack_id() {}
166 
167 Thread::ThreadEventData::~ThreadEventData() = default;
168 
169 void Thread::ThreadEventData::Dump(Stream *s) const {}
170 
171 const Thread::ThreadEventData *
172 Thread::ThreadEventData::GetEventDataFromEvent(const Event *event_ptr) {
173   if (event_ptr) {
174     const EventData *event_data = event_ptr->GetData();
175     if (event_data &&
176         event_data->GetFlavor() == ThreadEventData::GetFlavorString())
177       return static_cast<const ThreadEventData *>(event_ptr->GetData());
178   }
179   return nullptr;
180 }
181 
182 ThreadSP Thread::ThreadEventData::GetThreadFromEvent(const Event *event_ptr) {
183   ThreadSP thread_sp;
184   const ThreadEventData *event_data = GetEventDataFromEvent(event_ptr);
185   if (event_data)
186     thread_sp = event_data->GetThread();
187   return thread_sp;
188 }
189 
190 StackID Thread::ThreadEventData::GetStackIDFromEvent(const Event *event_ptr) {
191   StackID stack_id;
192   const ThreadEventData *event_data = GetEventDataFromEvent(event_ptr);
193   if (event_data)
194     stack_id = event_data->GetStackID();
195   return stack_id;
196 }
197 
198 StackFrameSP
199 Thread::ThreadEventData::GetStackFrameFromEvent(const Event *event_ptr) {
200   const ThreadEventData *event_data = GetEventDataFromEvent(event_ptr);
201   StackFrameSP frame_sp;
202   if (event_data) {
203     ThreadSP thread_sp = event_data->GetThread();
204     if (thread_sp) {
205       frame_sp = thread_sp->GetStackFrameList()->GetFrameWithStackID(
206           event_data->GetStackID());
207     }
208   }
209   return frame_sp;
210 }
211 
212 // Thread class
213 
214 llvm::StringRef Thread::GetStaticBroadcasterClass() {
215   static constexpr llvm::StringLiteral class_name("lldb.thread");
216   return class_name;
217 }
218 
219 Thread::Thread(Process &process, lldb::tid_t tid, bool use_invalid_index_id)
220     : ThreadProperties(false), UserID(tid),
221       Broadcaster(process.GetTarget().GetDebugger().GetBroadcasterManager(),
222                   Thread::GetStaticBroadcasterClass().str()),
223       m_process_wp(process.shared_from_this()), m_stop_info_sp(),
224       m_stop_info_stop_id(0), m_stop_info_override_stop_id(0),
225       m_should_run_before_public_stop(false),
226       m_index_id(use_invalid_index_id ? LLDB_INVALID_INDEX32
227                                       : process.GetNextThreadIndexID(tid)),
228       m_reg_context_sp(), m_state(eStateUnloaded), m_state_mutex(),
229       m_frame_mutex(), m_curr_frames_sp(), m_prev_frames_sp(),
230       m_prev_framezero_pc(), m_resume_signal(LLDB_INVALID_SIGNAL_NUMBER),
231       m_resume_state(eStateRunning), m_temporary_resume_state(eStateRunning),
232       m_unwinder_up(), m_destroy_called(false),
233       m_override_should_notify(eLazyBoolCalculate),
234       m_extended_info_fetched(false), m_extended_info() {
235   Log *log = GetLog(LLDBLog::Object);
236   LLDB_LOGF(log, "%p Thread::Thread(tid = 0x%4.4" PRIx64 ")",
237             static_cast<void *>(this), GetID());
238 
239   CheckInWithManager();
240 }
241 
242 Thread::~Thread() {
243   Log *log = GetLog(LLDBLog::Object);
244   LLDB_LOGF(log, "%p Thread::~Thread(tid = 0x%4.4" PRIx64 ")",
245             static_cast<void *>(this), GetID());
246   /// If you hit this assert, it means your derived class forgot to call
247   /// DestroyThread in its destructor.
248   assert(m_destroy_called);
249 }
250 
251 void Thread::DestroyThread() {
252   m_destroy_called = true;
253   m_stop_info_sp.reset();
254   m_reg_context_sp.reset();
255   m_unwinder_up.reset();
256   std::lock_guard<std::recursive_mutex> guard(m_frame_mutex);
257   m_curr_frames_sp.reset();
258   m_prev_frames_sp.reset();
259   m_prev_framezero_pc.reset();
260 }
261 
262 void Thread::BroadcastSelectedFrameChange(StackID &new_frame_id) {
263   if (EventTypeHasListeners(eBroadcastBitSelectedFrameChanged)) {
264     auto data_sp =
265         std::make_shared<ThreadEventData>(shared_from_this(), new_frame_id);
266     BroadcastEvent(eBroadcastBitSelectedFrameChanged, data_sp);
267   }
268 }
269 
270 lldb::StackFrameSP
271 Thread::GetSelectedFrame(SelectMostRelevant select_most_relevant) {
272   StackFrameListSP stack_frame_list_sp(GetStackFrameList());
273   StackFrameSP frame_sp = stack_frame_list_sp->GetFrameAtIndex(
274       stack_frame_list_sp->GetSelectedFrameIndex(select_most_relevant));
275   FrameSelectedCallback(frame_sp.get());
276   return frame_sp;
277 }
278 
279 uint32_t Thread::SetSelectedFrame(lldb_private::StackFrame *frame,
280                                   bool broadcast) {
281   uint32_t ret_value = GetStackFrameList()->SetSelectedFrame(frame);
282   if (broadcast)
283     BroadcastSelectedFrameChange(frame->GetStackID());
284   FrameSelectedCallback(frame);
285   return ret_value;
286 }
287 
288 bool Thread::SetSelectedFrameByIndex(uint32_t frame_idx, bool broadcast) {
289   StackFrameSP frame_sp(GetStackFrameList()->GetFrameAtIndex(frame_idx));
290   if (frame_sp) {
291     GetStackFrameList()->SetSelectedFrame(frame_sp.get());
292     if (broadcast)
293       BroadcastSelectedFrameChange(frame_sp->GetStackID());
294     FrameSelectedCallback(frame_sp.get());
295     return true;
296   } else
297     return false;
298 }
299 
300 bool Thread::SetSelectedFrameByIndexNoisily(uint32_t frame_idx,
301                                             Stream &output_stream) {
302   const bool broadcast = true;
303   bool success = SetSelectedFrameByIndex(frame_idx, broadcast);
304   if (success) {
305     StackFrameSP frame_sp = GetSelectedFrame(DoNoSelectMostRelevantFrame);
306     if (frame_sp) {
307       bool already_shown = false;
308       SymbolContext frame_sc(
309           frame_sp->GetSymbolContext(eSymbolContextLineEntry));
310       const Debugger &debugger = GetProcess()->GetTarget().GetDebugger();
311       if (debugger.GetUseExternalEditor() && frame_sc.line_entry.GetFile() &&
312           frame_sc.line_entry.line != 0) {
313         if (llvm::Error e = Host::OpenFileInExternalEditor(
314                 debugger.GetExternalEditor(), frame_sc.line_entry.GetFile(),
315                 frame_sc.line_entry.line)) {
316           LLDB_LOG_ERROR(GetLog(LLDBLog::Host), std::move(e),
317                          "OpenFileInExternalEditor failed: {0}");
318         } else {
319           already_shown = true;
320         }
321       }
322 
323       bool show_frame_info = true;
324       bool show_source = !already_shown;
325       FrameSelectedCallback(frame_sp.get());
326       return frame_sp->GetStatus(output_stream, show_frame_info, show_source);
327     }
328     return false;
329   } else
330     return false;
331 }
332 
333 void Thread::FrameSelectedCallback(StackFrame *frame) {
334   if (!frame)
335     return;
336 
337   if (frame->HasDebugInformation() &&
338       (GetProcess()->GetWarningsOptimization() ||
339        GetProcess()->GetWarningsUnsupportedLanguage())) {
340     SymbolContext sc =
341         frame->GetSymbolContext(eSymbolContextFunction | eSymbolContextModule);
342     GetProcess()->PrintWarningOptimization(sc);
343     GetProcess()->PrintWarningUnsupportedLanguage(sc);
344   }
345 }
346 
347 lldb::StopInfoSP Thread::GetStopInfo() {
348   if (m_destroy_called)
349     return m_stop_info_sp;
350 
351   ThreadPlanSP completed_plan_sp(GetCompletedPlan());
352   ProcessSP process_sp(GetProcess());
353   const uint32_t stop_id = process_sp ? process_sp->GetStopID() : UINT32_MAX;
354 
355   // Here we select the stop info according to priorirty: - m_stop_info_sp (if
356   // not trace) - preset value - completed plan stop info - new value with plan
357   // from completed plan stack - m_stop_info_sp (trace stop reason is OK now) -
358   // ask GetPrivateStopInfo to set stop info
359 
360   bool have_valid_stop_info = m_stop_info_sp &&
361       m_stop_info_sp ->IsValid() &&
362       m_stop_info_stop_id == stop_id;
363   bool have_valid_completed_plan = completed_plan_sp && completed_plan_sp->PlanSucceeded();
364   bool plan_failed = completed_plan_sp && !completed_plan_sp->PlanSucceeded();
365   bool plan_overrides_trace =
366     have_valid_stop_info && have_valid_completed_plan
367     && (m_stop_info_sp->GetStopReason() == eStopReasonTrace);
368 
369   if (have_valid_stop_info && !plan_overrides_trace && !plan_failed) {
370     return m_stop_info_sp;
371   } else if (completed_plan_sp) {
372     return StopInfo::CreateStopReasonWithPlan(
373         completed_plan_sp, GetReturnValueObject(), GetExpressionVariable());
374   } else {
375     GetPrivateStopInfo();
376     return m_stop_info_sp;
377   }
378 }
379 
380 void Thread::CalculatePublicStopInfo() {
381   ResetStopInfo();
382   SetStopInfo(GetStopInfo());
383 }
384 
385 lldb::StopInfoSP Thread::GetPrivateStopInfo(bool calculate) {
386   if (!calculate)
387     return m_stop_info_sp;
388 
389   if (m_destroy_called)
390     return m_stop_info_sp;
391 
392   ProcessSP process_sp(GetProcess());
393   if (process_sp) {
394     const uint32_t process_stop_id = process_sp->GetStopID();
395     if (m_stop_info_stop_id != process_stop_id) {
396       // We preserve the old stop info for a variety of reasons:
397       // 1) Someone has already updated it by the time we get here
398       // 2) We didn't get to execute the breakpoint instruction we stopped at
399       // 3) This is a virtual step so we didn't actually run
400       // 4) If this thread wasn't allowed to run the last time round.
401       if (m_stop_info_sp) {
402         if (m_stop_info_sp->IsValid() || IsStillAtLastBreakpointHit() ||
403             GetCurrentPlan()->IsVirtualStep()
404             || GetTemporaryResumeState() == eStateSuspended)
405           SetStopInfo(m_stop_info_sp);
406         else
407           m_stop_info_sp.reset();
408       }
409 
410       if (!m_stop_info_sp) {
411         if (!CalculateStopInfo())
412           SetStopInfo(StopInfoSP());
413       }
414     }
415 
416     // The stop info can be manually set by calling Thread::SetStopInfo() prior
417     // to this function ever getting called, so we can't rely on
418     // "m_stop_info_stop_id != process_stop_id" as the condition for the if
419     // statement below, we must also check the stop info to see if we need to
420     // override it. See the header documentation in
421     // Architecture::OverrideStopInfo() for more information on the stop
422     // info override callback.
423     if (m_stop_info_override_stop_id != process_stop_id) {
424       m_stop_info_override_stop_id = process_stop_id;
425       if (m_stop_info_sp) {
426         if (const Architecture *arch =
427                 process_sp->GetTarget().GetArchitecturePlugin())
428           arch->OverrideStopInfo(*this);
429       }
430     }
431   }
432 
433   // If we were resuming the process and it was interrupted,
434   // return no stop reason.  This thread would like to resume.
435   if (m_stop_info_sp && m_stop_info_sp->WasContinueInterrupted(*this))
436     return {};
437 
438   return m_stop_info_sp;
439 }
440 
441 lldb::StopReason Thread::GetStopReason() {
442   lldb::StopInfoSP stop_info_sp(GetStopInfo());
443   if (stop_info_sp)
444     return stop_info_sp->GetStopReason();
445   return eStopReasonNone;
446 }
447 
448 bool Thread::StopInfoIsUpToDate() const {
449   ProcessSP process_sp(GetProcess());
450   if (process_sp)
451     return m_stop_info_stop_id == process_sp->GetStopID();
452   else
453     return true; // Process is no longer around so stop info is always up to
454                  // date...
455 }
456 
457 void Thread::ResetStopInfo() {
458   if (m_stop_info_sp) {
459     m_stop_info_sp.reset();
460   }
461 }
462 
463 void Thread::SetStopInfo(const lldb::StopInfoSP &stop_info_sp) {
464   m_stop_info_sp = stop_info_sp;
465   if (m_stop_info_sp) {
466     m_stop_info_sp->MakeStopInfoValid();
467     // If we are overriding the ShouldReportStop, do that here:
468     if (m_override_should_notify != eLazyBoolCalculate)
469       m_stop_info_sp->OverrideShouldNotify(m_override_should_notify ==
470                                            eLazyBoolYes);
471   }
472 
473   ProcessSP process_sp(GetProcess());
474   if (process_sp)
475     m_stop_info_stop_id = process_sp->GetStopID();
476   else
477     m_stop_info_stop_id = UINT32_MAX;
478   Log *log = GetLog(LLDBLog::Thread);
479   LLDB_LOGF(log, "%p: tid = 0x%" PRIx64 ": stop info = %s (stop_id = %u)",
480             static_cast<void *>(this), GetID(),
481             stop_info_sp ? stop_info_sp->GetDescription() : "<NULL>",
482             m_stop_info_stop_id);
483 }
484 
485 void Thread::SetShouldReportStop(Vote vote) {
486   if (vote == eVoteNoOpinion)
487     return;
488   else {
489     m_override_should_notify = (vote == eVoteYes ? eLazyBoolYes : eLazyBoolNo);
490     if (m_stop_info_sp)
491       m_stop_info_sp->OverrideShouldNotify(m_override_should_notify ==
492                                            eLazyBoolYes);
493   }
494 }
495 
496 void Thread::SetStopInfoToNothing() {
497   // Note, we can't just NULL out the private reason, or the native thread
498   // implementation will try to go calculate it again.  For now, just set it to
499   // a Unix Signal with an invalid signal number.
500   SetStopInfo(
501       StopInfo::CreateStopReasonWithSignal(*this, LLDB_INVALID_SIGNAL_NUMBER));
502 }
503 
504 bool Thread::ThreadStoppedForAReason() { return (bool)GetPrivateStopInfo(); }
505 
506 bool Thread::CheckpointThreadState(ThreadStateCheckpoint &saved_state) {
507   saved_state.register_backup_sp.reset();
508   lldb::StackFrameSP frame_sp(GetStackFrameAtIndex(0));
509   if (frame_sp) {
510     lldb::RegisterCheckpointSP reg_checkpoint_sp(
511         new RegisterCheckpoint(RegisterCheckpoint::Reason::eExpression));
512     if (reg_checkpoint_sp) {
513       lldb::RegisterContextSP reg_ctx_sp(frame_sp->GetRegisterContext());
514       if (reg_ctx_sp && reg_ctx_sp->ReadAllRegisterValues(*reg_checkpoint_sp))
515         saved_state.register_backup_sp = reg_checkpoint_sp;
516     }
517   }
518   if (!saved_state.register_backup_sp)
519     return false;
520 
521   saved_state.stop_info_sp = GetStopInfo();
522   ProcessSP process_sp(GetProcess());
523   if (process_sp)
524     saved_state.orig_stop_id = process_sp->GetStopID();
525   saved_state.current_inlined_depth = GetCurrentInlinedDepth();
526   saved_state.m_completed_plan_checkpoint =
527       GetPlans().CheckpointCompletedPlans();
528 
529   return true;
530 }
531 
532 bool Thread::RestoreRegisterStateFromCheckpoint(
533     ThreadStateCheckpoint &saved_state) {
534   if (saved_state.register_backup_sp) {
535     lldb::StackFrameSP frame_sp(GetStackFrameAtIndex(0));
536     if (frame_sp) {
537       lldb::RegisterContextSP reg_ctx_sp(frame_sp->GetRegisterContext());
538       if (reg_ctx_sp) {
539         bool ret =
540             reg_ctx_sp->WriteAllRegisterValues(*saved_state.register_backup_sp);
541 
542         // Clear out all stack frames as our world just changed.
543         ClearStackFrames();
544         reg_ctx_sp->InvalidateIfNeeded(true);
545         if (m_unwinder_up)
546           m_unwinder_up->Clear();
547         return ret;
548       }
549     }
550   }
551   return false;
552 }
553 
554 void Thread::RestoreThreadStateFromCheckpoint(
555     ThreadStateCheckpoint &saved_state) {
556   if (saved_state.stop_info_sp)
557     saved_state.stop_info_sp->MakeStopInfoValid();
558   SetStopInfo(saved_state.stop_info_sp);
559   GetStackFrameList()->SetCurrentInlinedDepth(
560       saved_state.current_inlined_depth);
561   GetPlans().RestoreCompletedPlanCheckpoint(
562       saved_state.m_completed_plan_checkpoint);
563 }
564 
565 StateType Thread::GetState() const {
566   // If any other threads access this we will need a mutex for it
567   std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
568   return m_state;
569 }
570 
571 void Thread::SetState(StateType state) {
572   std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
573   m_state = state;
574 }
575 
576 std::string Thread::GetStopDescription() {
577   StackFrameSP frame_sp = GetStackFrameAtIndex(0);
578 
579   if (!frame_sp)
580     return GetStopDescriptionRaw();
581 
582   auto recognized_frame_sp = frame_sp->GetRecognizedFrame();
583 
584   if (!recognized_frame_sp)
585     return GetStopDescriptionRaw();
586 
587   std::string recognized_stop_description =
588       recognized_frame_sp->GetStopDescription();
589 
590   if (!recognized_stop_description.empty())
591     return recognized_stop_description;
592 
593   return GetStopDescriptionRaw();
594 }
595 
596 std::string Thread::GetStopDescriptionRaw() {
597   StopInfoSP stop_info_sp = GetStopInfo();
598   std::string raw_stop_description;
599   if (stop_info_sp && stop_info_sp->IsValid()) {
600     raw_stop_description = stop_info_sp->GetDescription();
601     assert((!raw_stop_description.empty() ||
602             stop_info_sp->GetStopReason() == eStopReasonNone) &&
603            "StopInfo returned an empty description.");
604   }
605   return raw_stop_description;
606 }
607 
608 void Thread::WillStop() {
609   ThreadPlan *current_plan = GetCurrentPlan();
610 
611   // FIXME: I may decide to disallow threads with no plans.  In which
612   // case this should go to an assert.
613 
614   if (!current_plan)
615     return;
616 
617   current_plan->WillStop();
618 }
619 
620 bool Thread::SetupForResume() {
621   if (GetResumeState() != eStateSuspended) {
622     // First check whether this thread is going to "actually" resume at all.
623     // For instance, if we're stepping from one level to the next of an
624     // virtual inlined call stack, we just change the inlined call stack index
625     // without actually running this thread.  In that case, for this thread we
626     // shouldn't push a step over breakpoint plan or do that work.
627     if (GetCurrentPlan()->IsVirtualStep())
628       return false;
629 
630     // If we're at a breakpoint push the step-over breakpoint plan.  Do this
631     // before telling the current plan it will resume, since we might change
632     // what the current plan is.
633 
634     lldb::RegisterContextSP reg_ctx_sp(GetRegisterContext());
635     if (reg_ctx_sp) {
636       const addr_t thread_pc = reg_ctx_sp->GetPC();
637       BreakpointSiteSP bp_site_sp =
638           GetProcess()->GetBreakpointSiteList().FindByAddress(thread_pc);
639       if (bp_site_sp) {
640         // Note, don't assume there's a ThreadPlanStepOverBreakpoint, the
641         // target may not require anything special to step over a breakpoint.
642 
643         ThreadPlan *cur_plan = GetCurrentPlan();
644 
645         bool push_step_over_bp_plan = false;
646         if (cur_plan->GetKind() == ThreadPlan::eKindStepOverBreakpoint) {
647           ThreadPlanStepOverBreakpoint *bp_plan =
648               (ThreadPlanStepOverBreakpoint *)cur_plan;
649           if (bp_plan->GetBreakpointLoadAddress() != thread_pc)
650             push_step_over_bp_plan = true;
651         } else
652           push_step_over_bp_plan = true;
653 
654         if (push_step_over_bp_plan) {
655           ThreadPlanSP step_bp_plan_sp(new ThreadPlanStepOverBreakpoint(*this));
656           if (step_bp_plan_sp) {
657             step_bp_plan_sp->SetPrivate(true);
658 
659             if (GetCurrentPlan()->RunState() != eStateStepping) {
660               ThreadPlanStepOverBreakpoint *step_bp_plan =
661                   static_cast<ThreadPlanStepOverBreakpoint *>(
662                       step_bp_plan_sp.get());
663               step_bp_plan->SetAutoContinue(true);
664             }
665             QueueThreadPlan(step_bp_plan_sp, false);
666             return true;
667           }
668         }
669       }
670     }
671   }
672   return false;
673 }
674 
675 bool Thread::ShouldResume(StateType resume_state) {
676   // At this point clear the completed plan stack.
677   GetPlans().WillResume();
678   m_override_should_notify = eLazyBoolCalculate;
679 
680   StateType prev_resume_state = GetTemporaryResumeState();
681 
682   SetTemporaryResumeState(resume_state);
683 
684   lldb::ThreadSP backing_thread_sp(GetBackingThread());
685   if (backing_thread_sp)
686     backing_thread_sp->SetTemporaryResumeState(resume_state);
687 
688   // Make sure m_stop_info_sp is valid.  Don't do this for threads we suspended
689   // in the previous run.
690   if (prev_resume_state != eStateSuspended)
691     GetPrivateStopInfo();
692 
693   // This is a little dubious, but we are trying to limit how often we actually
694   // fetch stop info from the target, 'cause that slows down single stepping.
695   // So assume that if we got to the point where we're about to resume, and we
696   // haven't yet had to fetch the stop reason, then it doesn't need to know
697   // about the fact that we are resuming...
698   const uint32_t process_stop_id = GetProcess()->GetStopID();
699   if (m_stop_info_stop_id == process_stop_id &&
700       (m_stop_info_sp && m_stop_info_sp->IsValid())) {
701     StopInfo *stop_info = GetPrivateStopInfo().get();
702     if (stop_info)
703       stop_info->WillResume(resume_state);
704   }
705 
706   // Tell all the plans that we are about to resume in case they need to clear
707   // any state. We distinguish between the plan on the top of the stack and the
708   // lower plans in case a plan needs to do any special business before it
709   // runs.
710 
711   bool need_to_resume = false;
712   ThreadPlan *plan_ptr = GetCurrentPlan();
713   if (plan_ptr) {
714     need_to_resume = plan_ptr->WillResume(resume_state, true);
715 
716     while ((plan_ptr = GetPreviousPlan(plan_ptr)) != nullptr) {
717       plan_ptr->WillResume(resume_state, false);
718     }
719 
720     // If the WillResume for the plan says we are faking a resume, then it will
721     // have set an appropriate stop info. In that case, don't reset it here.
722 
723     if (need_to_resume && resume_state != eStateSuspended) {
724       m_stop_info_sp.reset();
725     }
726   }
727 
728   if (need_to_resume) {
729     ClearStackFrames();
730     // Let Thread subclasses do any special work they need to prior to resuming
731     WillResume(resume_state);
732   }
733 
734   return need_to_resume;
735 }
736 
737 void Thread::DidResume() {
738   SetResumeSignal(LLDB_INVALID_SIGNAL_NUMBER);
739   // This will get recomputed each time when we stop.
740   SetShouldRunBeforePublicStop(false);
741 }
742 
743 void Thread::DidStop() { SetState(eStateStopped); }
744 
745 bool Thread::ShouldStop(Event *event_ptr) {
746   ThreadPlan *current_plan = GetCurrentPlan();
747 
748   bool should_stop = true;
749 
750   Log *log = GetLog(LLDBLog::Step);
751 
752   if (GetResumeState() == eStateSuspended) {
753     LLDB_LOGF(log,
754               "Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64
755               ", should_stop = 0 (ignore since thread was suspended)",
756               __FUNCTION__, GetID(), GetProtocolID());
757     return false;
758   }
759 
760   if (GetTemporaryResumeState() == eStateSuspended) {
761     LLDB_LOGF(log,
762               "Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64
763               ", should_stop = 0 (ignore since thread was suspended)",
764               __FUNCTION__, GetID(), GetProtocolID());
765     return false;
766   }
767 
768   // Based on the current thread plan and process stop info, check if this
769   // thread caused the process to stop. NOTE: this must take place before the
770   // plan is moved from the current plan stack to the completed plan stack.
771   if (!ThreadStoppedForAReason()) {
772     LLDB_LOGF(log,
773               "Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64
774               ", pc = 0x%16.16" PRIx64
775               ", should_stop = 0 (ignore since no stop reason)",
776               __FUNCTION__, GetID(), GetProtocolID(),
777               GetRegisterContext() ? GetRegisterContext()->GetPC()
778                                    : LLDB_INVALID_ADDRESS);
779     return false;
780   }
781 
782   // Clear the "must run me before stop" if it was set:
783   SetShouldRunBeforePublicStop(false);
784 
785   if (log) {
786     LLDB_LOGF(log,
787               "Thread::%s(%p) for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64
788               ", pc = 0x%16.16" PRIx64,
789               __FUNCTION__, static_cast<void *>(this), GetID(), GetProtocolID(),
790               GetRegisterContext() ? GetRegisterContext()->GetPC()
791                                    : LLDB_INVALID_ADDRESS);
792     LLDB_LOGF(log, "^^^^^^^^ Thread::ShouldStop Begin ^^^^^^^^");
793     StreamString s;
794     s.IndentMore();
795     GetProcess()->DumpThreadPlansForTID(
796         s, GetID(), eDescriptionLevelVerbose, true /* internal */,
797         false /* condense_trivial */, true /* skip_unreported */);
798     LLDB_LOGF(log, "Plan stack initial state:\n%s", s.GetData());
799   }
800 
801   // The top most plan always gets to do the trace log...
802   current_plan->DoTraceLog();
803 
804   // First query the stop info's ShouldStopSynchronous.  This handles
805   // "synchronous" stop reasons, for example the breakpoint command on internal
806   // breakpoints.  If a synchronous stop reason says we should not stop, then
807   // we don't have to do any more work on this stop.
808   StopInfoSP private_stop_info(GetPrivateStopInfo());
809   if (private_stop_info &&
810       !private_stop_info->ShouldStopSynchronous(event_ptr)) {
811     LLDB_LOGF(log, "StopInfo::ShouldStop async callback says we should not "
812                    "stop, returning ShouldStop of false.");
813     return false;
814   }
815 
816   // If we've already been restarted, don't query the plans since the state
817   // they would examine is not current.
818   if (Process::ProcessEventData::GetRestartedFromEvent(event_ptr))
819     return false;
820 
821   // Before the plans see the state of the world, calculate the current inlined
822   // depth.
823   GetStackFrameList()->CalculateCurrentInlinedDepth();
824 
825   // If the base plan doesn't understand why we stopped, then we have to find a
826   // plan that does. If that plan is still working, then we don't need to do
827   // any more work.  If the plan that explains the stop is done, then we should
828   // pop all the plans below it, and pop it, and then let the plans above it
829   // decide whether they still need to do more work.
830 
831   bool done_processing_current_plan = false;
832   if (!current_plan->PlanExplainsStop(event_ptr)) {
833     if (current_plan->TracerExplainsStop()) {
834       done_processing_current_plan = true;
835       should_stop = false;
836     } else {
837       // Leaf plan that does not explain the stop should be popped.
838       // The plan should be push itself later again before resuming to stay
839       // as leaf.
840       if (current_plan->IsLeafPlan())
841         PopPlan();
842 
843       // If the current plan doesn't explain the stop, then find one that does
844       // and let it handle the situation.
845       ThreadPlan *plan_ptr = current_plan;
846       while ((plan_ptr = GetPreviousPlan(plan_ptr)) != nullptr) {
847         if (plan_ptr->PlanExplainsStop(event_ptr)) {
848           LLDB_LOGF(log, "Plan %s explains stop.", plan_ptr->GetName());
849 
850           should_stop = plan_ptr->ShouldStop(event_ptr);
851 
852           // plan_ptr explains the stop, next check whether plan_ptr is done,
853           // if so, then we should take it and all the plans below it off the
854           // stack.
855 
856           if (plan_ptr->MischiefManaged()) {
857             // We're going to pop the plans up to and including the plan that
858             // explains the stop.
859             ThreadPlan *prev_plan_ptr = GetPreviousPlan(plan_ptr);
860 
861             do {
862               if (should_stop)
863                 current_plan->WillStop();
864               PopPlan();
865             } while ((current_plan = GetCurrentPlan()) != prev_plan_ptr);
866             // Now, if the responsible plan was not "Okay to discard" then
867             // we're done, otherwise we forward this to the next plan in the
868             // stack below.
869             done_processing_current_plan =
870                 (plan_ptr->IsControllingPlan() && !plan_ptr->OkayToDiscard());
871           } else {
872             bool should_force_run = plan_ptr->ShouldRunBeforePublicStop();
873             if (should_force_run) {
874               SetShouldRunBeforePublicStop(true);
875               should_stop = false;
876             }
877             done_processing_current_plan = true;
878           }
879           break;
880         }
881       }
882     }
883   }
884 
885   if (!done_processing_current_plan) {
886     bool override_stop = false;
887 
888     // We're starting from the base plan, so just let it decide;
889     if (current_plan->IsBasePlan()) {
890       should_stop = current_plan->ShouldStop(event_ptr);
891       LLDB_LOGF(log, "Base plan says should stop: %i.", should_stop);
892     } else {
893       // Otherwise, don't let the base plan override what the other plans say
894       // to do, since presumably if there were other plans they would know what
895       // to do...
896       while (true) {
897         if (current_plan->IsBasePlan())
898           break;
899 
900         should_stop = current_plan->ShouldStop(event_ptr);
901         LLDB_LOGF(log, "Plan %s should stop: %d.", current_plan->GetName(),
902                   should_stop);
903         if (current_plan->MischiefManaged()) {
904           if (should_stop)
905             current_plan->WillStop();
906 
907           if (current_plan->ShouldAutoContinue(event_ptr)) {
908             override_stop = true;
909             LLDB_LOGF(log, "Plan %s auto-continue: true.",
910                       current_plan->GetName());
911           }
912 
913           // If a Controlling Plan wants to stop, we let it. Otherwise, see if
914           // the plan's parent wants to stop.
915 
916           PopPlan();
917           if (should_stop && current_plan->IsControllingPlan() &&
918               !current_plan->OkayToDiscard()) {
919             break;
920           }
921 
922           current_plan = GetCurrentPlan();
923           if (current_plan == nullptr) {
924             break;
925           }
926         } else {
927           break;
928         }
929       }
930     }
931 
932     if (override_stop)
933       should_stop = false;
934   }
935 
936   // One other potential problem is that we set up a controlling plan, then stop
937   // in before it is complete - for instance by hitting a breakpoint during a
938   // step-over - then do some step/finish/etc operations that wind up past the
939   // end point condition of the initial plan.  We don't want to strand the
940   // original plan on the stack, This code clears stale plans off the stack.
941 
942   if (should_stop) {
943     ThreadPlan *plan_ptr = GetCurrentPlan();
944 
945     // Discard the stale plans and all plans below them in the stack, plus move
946     // the completed plans to the completed plan stack
947     while (!plan_ptr->IsBasePlan()) {
948       bool stale = plan_ptr->IsPlanStale();
949       ThreadPlan *examined_plan = plan_ptr;
950       plan_ptr = GetPreviousPlan(examined_plan);
951 
952       if (stale) {
953         LLDB_LOGF(
954             log,
955             "Plan %s being discarded in cleanup, it says it is already done.",
956             examined_plan->GetName());
957         while (GetCurrentPlan() != examined_plan) {
958           DiscardPlan();
959         }
960         if (examined_plan->IsPlanComplete()) {
961           // plan is complete but does not explain the stop (example: step to a
962           // line with breakpoint), let us move the plan to
963           // completed_plan_stack anyway
964           PopPlan();
965         } else
966           DiscardPlan();
967       }
968     }
969   }
970 
971   if (log) {
972     StreamString s;
973     s.IndentMore();
974     GetProcess()->DumpThreadPlansForTID(
975         s, GetID(), eDescriptionLevelVerbose, true /* internal */,
976         false /* condense_trivial */, true /* skip_unreported */);
977     LLDB_LOGF(log, "Plan stack final state:\n%s", s.GetData());
978     LLDB_LOGF(log, "vvvvvvvv Thread::ShouldStop End (returning %i) vvvvvvvv",
979               should_stop);
980   }
981   return should_stop;
982 }
983 
984 Vote Thread::ShouldReportStop(Event *event_ptr) {
985   StateType thread_state = GetResumeState();
986   StateType temp_thread_state = GetTemporaryResumeState();
987 
988   Log *log = GetLog(LLDBLog::Step);
989 
990   if (thread_state == eStateSuspended || thread_state == eStateInvalid) {
991     LLDB_LOGF(log,
992               "Thread::ShouldReportStop() tid = 0x%4.4" PRIx64
993               ": returning vote %i (state was suspended or invalid)",
994               GetID(), eVoteNoOpinion);
995     return eVoteNoOpinion;
996   }
997 
998   if (temp_thread_state == eStateSuspended ||
999       temp_thread_state == eStateInvalid) {
1000     LLDB_LOGF(log,
1001               "Thread::ShouldReportStop() tid = 0x%4.4" PRIx64
1002               ": returning vote %i (temporary state was suspended or invalid)",
1003               GetID(), eVoteNoOpinion);
1004     return eVoteNoOpinion;
1005   }
1006 
1007   if (!ThreadStoppedForAReason()) {
1008     LLDB_LOGF(log,
1009               "Thread::ShouldReportStop() tid = 0x%4.4" PRIx64
1010               ": returning vote %i (thread didn't stop for a reason.)",
1011               GetID(), eVoteNoOpinion);
1012     return eVoteNoOpinion;
1013   }
1014 
1015   if (GetPlans().AnyCompletedPlans()) {
1016     // Pass skip_private = false to GetCompletedPlan, since we want to ask
1017     // the last plan, regardless of whether it is private or not.
1018     LLDB_LOGF(log,
1019               "Thread::ShouldReportStop() tid = 0x%4.4" PRIx64
1020               ": returning vote for complete stack's back plan",
1021               GetID());
1022     return GetPlans().GetCompletedPlan(false)->ShouldReportStop(event_ptr);
1023   } else {
1024     Vote thread_vote = eVoteNoOpinion;
1025     ThreadPlan *plan_ptr = GetCurrentPlan();
1026     while (true) {
1027       if (plan_ptr->PlanExplainsStop(event_ptr)) {
1028         thread_vote = plan_ptr->ShouldReportStop(event_ptr);
1029         break;
1030       }
1031       if (plan_ptr->IsBasePlan())
1032         break;
1033       else
1034         plan_ptr = GetPreviousPlan(plan_ptr);
1035     }
1036     LLDB_LOGF(log,
1037               "Thread::ShouldReportStop() tid = 0x%4.4" PRIx64
1038               ": returning vote %i for current plan",
1039               GetID(), thread_vote);
1040 
1041     return thread_vote;
1042   }
1043 }
1044 
1045 Vote Thread::ShouldReportRun(Event *event_ptr) {
1046   StateType thread_state = GetResumeState();
1047 
1048   if (thread_state == eStateSuspended || thread_state == eStateInvalid) {
1049     return eVoteNoOpinion;
1050   }
1051 
1052   Log *log = GetLog(LLDBLog::Step);
1053   if (GetPlans().AnyCompletedPlans()) {
1054     // Pass skip_private = false to GetCompletedPlan, since we want to ask
1055     // the last plan, regardless of whether it is private or not.
1056     LLDB_LOGF(log,
1057               "Current Plan for thread %d(%p) (0x%4.4" PRIx64
1058               ", %s): %s being asked whether we should report run.",
1059               GetIndexID(), static_cast<void *>(this), GetID(),
1060               StateAsCString(GetTemporaryResumeState()),
1061               GetCompletedPlan()->GetName());
1062 
1063     return GetPlans().GetCompletedPlan(false)->ShouldReportRun(event_ptr);
1064   } else {
1065     LLDB_LOGF(log,
1066               "Current Plan for thread %d(%p) (0x%4.4" PRIx64
1067               ", %s): %s being asked whether we should report run.",
1068               GetIndexID(), static_cast<void *>(this), GetID(),
1069               StateAsCString(GetTemporaryResumeState()),
1070               GetCurrentPlan()->GetName());
1071 
1072     return GetCurrentPlan()->ShouldReportRun(event_ptr);
1073   }
1074 }
1075 
1076 bool Thread::MatchesSpec(const ThreadSpec *spec) {
1077   return (spec == nullptr) ? true : spec->ThreadPassesBasicTests(*this);
1078 }
1079 
1080 ThreadPlanStack &Thread::GetPlans() const {
1081   ThreadPlanStack *plans = GetProcess()->FindThreadPlans(GetID());
1082   if (plans)
1083     return *plans;
1084 
1085   // History threads don't have a thread plan, but they do ask get asked to
1086   // describe themselves, which usually involves pulling out the stop reason.
1087   // That in turn will check for a completed plan on the ThreadPlanStack.
1088   // Instead of special-casing at that point, we return a Stack with a
1089   // ThreadPlanNull as its base plan.  That will give the right answers to the
1090   // queries GetDescription makes, and only assert if you try to run the thread.
1091   if (!m_null_plan_stack_up)
1092     m_null_plan_stack_up = std::make_unique<ThreadPlanStack>(*this, true);
1093   return *m_null_plan_stack_up;
1094 }
1095 
1096 void Thread::PushPlan(ThreadPlanSP thread_plan_sp) {
1097   assert(thread_plan_sp && "Don't push an empty thread plan.");
1098 
1099   Log *log = GetLog(LLDBLog::Step);
1100   if (log) {
1101     StreamString s;
1102     thread_plan_sp->GetDescription(&s, lldb::eDescriptionLevelFull);
1103     LLDB_LOGF(log, "Thread::PushPlan(0x%p): \"%s\", tid = 0x%4.4" PRIx64 ".",
1104               static_cast<void *>(this), s.GetData(),
1105               thread_plan_sp->GetThread().GetID());
1106   }
1107 
1108   GetPlans().PushPlan(std::move(thread_plan_sp));
1109 }
1110 
1111 void Thread::PopPlan() {
1112   Log *log = GetLog(LLDBLog::Step);
1113   ThreadPlanSP popped_plan_sp = GetPlans().PopPlan();
1114   if (log) {
1115     LLDB_LOGF(log, "Popping plan: \"%s\", tid = 0x%4.4" PRIx64 ".",
1116               popped_plan_sp->GetName(), popped_plan_sp->GetThread().GetID());
1117   }
1118 }
1119 
1120 void Thread::DiscardPlan() {
1121   Log *log = GetLog(LLDBLog::Step);
1122   ThreadPlanSP discarded_plan_sp = GetPlans().DiscardPlan();
1123 
1124   LLDB_LOGF(log, "Discarding plan: \"%s\", tid = 0x%4.4" PRIx64 ".",
1125             discarded_plan_sp->GetName(),
1126             discarded_plan_sp->GetThread().GetID());
1127 }
1128 
1129 void Thread::AutoCompleteThreadPlans(CompletionRequest &request) const {
1130   const ThreadPlanStack &plans = GetPlans();
1131   if (!plans.AnyPlans())
1132     return;
1133 
1134   // Iterate from the second plan (index: 1) to skip the base plan.
1135   ThreadPlanSP p;
1136   uint32_t i = 1;
1137   while ((p = plans.GetPlanByIndex(i, false))) {
1138     StreamString strm;
1139     p->GetDescription(&strm, eDescriptionLevelInitial);
1140     request.TryCompleteCurrentArg(std::to_string(i), strm.GetString());
1141     i++;
1142   }
1143 }
1144 
1145 ThreadPlan *Thread::GetCurrentPlan() const {
1146   return GetPlans().GetCurrentPlan().get();
1147 }
1148 
1149 ThreadPlanSP Thread::GetCompletedPlan() const {
1150   return GetPlans().GetCompletedPlan();
1151 }
1152 
1153 ValueObjectSP Thread::GetReturnValueObject() const {
1154   return GetPlans().GetReturnValueObject();
1155 }
1156 
1157 ExpressionVariableSP Thread::GetExpressionVariable() const {
1158   return GetPlans().GetExpressionVariable();
1159 }
1160 
1161 bool Thread::IsThreadPlanDone(ThreadPlan *plan) const {
1162   return GetPlans().IsPlanDone(plan);
1163 }
1164 
1165 bool Thread::WasThreadPlanDiscarded(ThreadPlan *plan) const {
1166   return GetPlans().WasPlanDiscarded(plan);
1167 }
1168 
1169 bool Thread::CompletedPlanOverridesBreakpoint() const {
1170   return GetPlans().AnyCompletedPlans();
1171 }
1172 
1173 ThreadPlan *Thread::GetPreviousPlan(ThreadPlan *current_plan) const{
1174   return GetPlans().GetPreviousPlan(current_plan);
1175 }
1176 
1177 Status Thread::QueueThreadPlan(ThreadPlanSP &thread_plan_sp,
1178                                bool abort_other_plans) {
1179   Status status;
1180   StreamString s;
1181   if (!thread_plan_sp->ValidatePlan(&s)) {
1182     DiscardThreadPlansUpToPlan(thread_plan_sp);
1183     thread_plan_sp.reset();
1184     return Status(s.GetString().str());
1185   }
1186 
1187   if (abort_other_plans)
1188     DiscardThreadPlans(true);
1189 
1190   PushPlan(thread_plan_sp);
1191 
1192   // This seems a little funny, but I don't want to have to split up the
1193   // constructor and the DidPush in the scripted plan, that seems annoying.
1194   // That means the constructor has to be in DidPush. So I have to validate the
1195   // plan AFTER pushing it, and then take it off again...
1196   if (!thread_plan_sp->ValidatePlan(&s)) {
1197     DiscardThreadPlansUpToPlan(thread_plan_sp);
1198     thread_plan_sp.reset();
1199     return Status(s.GetString().str());
1200   }
1201 
1202   return status;
1203 }
1204 
1205 bool Thread::DiscardUserThreadPlansUpToIndex(uint32_t plan_index) {
1206   // Count the user thread plans from the back end to get the number of the one
1207   // we want to discard:
1208 
1209   ThreadPlan *up_to_plan_ptr = GetPlans().GetPlanByIndex(plan_index).get();
1210   if (up_to_plan_ptr == nullptr)
1211     return false;
1212 
1213   DiscardThreadPlansUpToPlan(up_to_plan_ptr);
1214   return true;
1215 }
1216 
1217 void Thread::DiscardThreadPlansUpToPlan(lldb::ThreadPlanSP &up_to_plan_sp) {
1218   DiscardThreadPlansUpToPlan(up_to_plan_sp.get());
1219 }
1220 
1221 void Thread::DiscardThreadPlansUpToPlan(ThreadPlan *up_to_plan_ptr) {
1222   Log *log = GetLog(LLDBLog::Step);
1223   LLDB_LOGF(log,
1224             "Discarding thread plans for thread tid = 0x%4.4" PRIx64
1225             ", up to %p",
1226             GetID(), static_cast<void *>(up_to_plan_ptr));
1227   GetPlans().DiscardPlansUpToPlan(up_to_plan_ptr);
1228 }
1229 
1230 void Thread::DiscardThreadPlans(bool force) {
1231   Log *log = GetLog(LLDBLog::Step);
1232   if (log) {
1233     LLDB_LOGF(log,
1234               "Discarding thread plans for thread (tid = 0x%4.4" PRIx64
1235               ", force %d)",
1236               GetID(), force);
1237   }
1238 
1239   if (force) {
1240     GetPlans().DiscardAllPlans();
1241     return;
1242   }
1243   GetPlans().DiscardConsultingControllingPlans();
1244 }
1245 
1246 Status Thread::UnwindInnermostExpression() {
1247   Status error;
1248   ThreadPlan *innermost_expr_plan = GetPlans().GetInnermostExpression();
1249   if (!innermost_expr_plan) {
1250     error = Status::FromErrorString(
1251         "No expressions currently active on this thread");
1252     return error;
1253   }
1254   DiscardThreadPlansUpToPlan(innermost_expr_plan);
1255   return error;
1256 }
1257 
1258 ThreadPlanSP Thread::QueueBasePlan(bool abort_other_plans) {
1259   ThreadPlanSP thread_plan_sp(new ThreadPlanBase(*this));
1260   QueueThreadPlan(thread_plan_sp, abort_other_plans);
1261   return thread_plan_sp;
1262 }
1263 
1264 ThreadPlanSP Thread::QueueThreadPlanForStepSingleInstruction(
1265     bool step_over, bool abort_other_plans, bool stop_other_threads,
1266     Status &status) {
1267   ThreadPlanSP thread_plan_sp(new ThreadPlanStepInstruction(
1268       *this, step_over, stop_other_threads, eVoteNoOpinion, eVoteNoOpinion));
1269   status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
1270   return thread_plan_sp;
1271 }
1272 
1273 ThreadPlanSP Thread::QueueThreadPlanForStepOverRange(
1274     bool abort_other_plans, const AddressRange &range,
1275     const SymbolContext &addr_context, lldb::RunMode stop_other_threads,
1276     Status &status, LazyBool step_out_avoids_code_withoug_debug_info) {
1277   ThreadPlanSP thread_plan_sp;
1278   thread_plan_sp = std::make_shared<ThreadPlanStepOverRange>(
1279       *this, range, addr_context, stop_other_threads,
1280       step_out_avoids_code_withoug_debug_info);
1281 
1282   status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
1283   return thread_plan_sp;
1284 }
1285 
1286 // Call the QueueThreadPlanForStepOverRange method which takes an address
1287 // range.
1288 ThreadPlanSP Thread::QueueThreadPlanForStepOverRange(
1289     bool abort_other_plans, const LineEntry &line_entry,
1290     const SymbolContext &addr_context, lldb::RunMode stop_other_threads,
1291     Status &status, LazyBool step_out_avoids_code_withoug_debug_info) {
1292   const bool include_inlined_functions = true;
1293   auto address_range =
1294       line_entry.GetSameLineContiguousAddressRange(include_inlined_functions);
1295   return QueueThreadPlanForStepOverRange(
1296       abort_other_plans, address_range, addr_context, stop_other_threads,
1297       status, step_out_avoids_code_withoug_debug_info);
1298 }
1299 
1300 ThreadPlanSP Thread::QueueThreadPlanForStepInRange(
1301     bool abort_other_plans, const AddressRange &range,
1302     const SymbolContext &addr_context, const char *step_in_target,
1303     lldb::RunMode stop_other_threads, Status &status,
1304     LazyBool step_in_avoids_code_without_debug_info,
1305     LazyBool step_out_avoids_code_without_debug_info) {
1306   ThreadPlanSP thread_plan_sp(new ThreadPlanStepInRange(
1307       *this, range, addr_context, step_in_target, stop_other_threads,
1308       step_in_avoids_code_without_debug_info,
1309       step_out_avoids_code_without_debug_info));
1310   status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
1311   return thread_plan_sp;
1312 }
1313 
1314 // Call the QueueThreadPlanForStepInRange method which takes an address range.
1315 ThreadPlanSP Thread::QueueThreadPlanForStepInRange(
1316     bool abort_other_plans, const LineEntry &line_entry,
1317     const SymbolContext &addr_context, const char *step_in_target,
1318     lldb::RunMode stop_other_threads, Status &status,
1319     LazyBool step_in_avoids_code_without_debug_info,
1320     LazyBool step_out_avoids_code_without_debug_info) {
1321   const bool include_inlined_functions = false;
1322   return QueueThreadPlanForStepInRange(
1323       abort_other_plans,
1324       line_entry.GetSameLineContiguousAddressRange(include_inlined_functions),
1325       addr_context, step_in_target, stop_other_threads, status,
1326       step_in_avoids_code_without_debug_info,
1327       step_out_avoids_code_without_debug_info);
1328 }
1329 
1330 ThreadPlanSP Thread::QueueThreadPlanForStepOut(
1331     bool abort_other_plans, SymbolContext *addr_context, bool first_insn,
1332     bool stop_other_threads, Vote report_stop_vote, Vote report_run_vote,
1333     uint32_t frame_idx, Status &status,
1334     LazyBool step_out_avoids_code_without_debug_info) {
1335   ThreadPlanSP thread_plan_sp(new ThreadPlanStepOut(
1336       *this, addr_context, first_insn, stop_other_threads, report_stop_vote,
1337       report_run_vote, frame_idx, step_out_avoids_code_without_debug_info));
1338 
1339   status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
1340   return thread_plan_sp;
1341 }
1342 
1343 ThreadPlanSP Thread::QueueThreadPlanForStepOutNoShouldStop(
1344     bool abort_other_plans, SymbolContext *addr_context, bool first_insn,
1345     bool stop_other_threads, Vote report_stop_vote, Vote report_run_vote,
1346     uint32_t frame_idx, Status &status, bool continue_to_next_branch) {
1347   const bool calculate_return_value =
1348       false; // No need to calculate the return value here.
1349   ThreadPlanSP thread_plan_sp(new ThreadPlanStepOut(
1350       *this, addr_context, first_insn, stop_other_threads, report_stop_vote,
1351       report_run_vote, frame_idx, eLazyBoolNo, continue_to_next_branch,
1352       calculate_return_value));
1353 
1354   ThreadPlanStepOut *new_plan =
1355       static_cast<ThreadPlanStepOut *>(thread_plan_sp.get());
1356   new_plan->ClearShouldStopHereCallbacks();
1357 
1358   status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
1359   return thread_plan_sp;
1360 }
1361 
1362 ThreadPlanSP Thread::QueueThreadPlanForStepThrough(StackID &return_stack_id,
1363                                                    bool abort_other_plans,
1364                                                    bool stop_other_threads,
1365                                                    Status &status) {
1366   ThreadPlanSP thread_plan_sp(
1367       new ThreadPlanStepThrough(*this, return_stack_id, stop_other_threads));
1368   if (!thread_plan_sp || !thread_plan_sp->ValidatePlan(nullptr))
1369     return ThreadPlanSP();
1370 
1371   status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
1372   return thread_plan_sp;
1373 }
1374 
1375 ThreadPlanSP Thread::QueueThreadPlanForRunToAddress(bool abort_other_plans,
1376                                                     Address &target_addr,
1377                                                     bool stop_other_threads,
1378                                                     Status &status) {
1379   ThreadPlanSP thread_plan_sp(
1380       new ThreadPlanRunToAddress(*this, target_addr, stop_other_threads));
1381 
1382   status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
1383   return thread_plan_sp;
1384 }
1385 
1386 ThreadPlanSP Thread::QueueThreadPlanForStepUntil(
1387     bool abort_other_plans, lldb::addr_t *address_list, size_t num_addresses,
1388     bool stop_other_threads, uint32_t frame_idx, Status &status) {
1389   ThreadPlanSP thread_plan_sp(new ThreadPlanStepUntil(
1390       *this, address_list, num_addresses, stop_other_threads, frame_idx));
1391 
1392   status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
1393   return thread_plan_sp;
1394 }
1395 
1396 lldb::ThreadPlanSP Thread::QueueThreadPlanForStepScripted(
1397     bool abort_other_plans, const char *class_name,
1398     StructuredData::ObjectSP extra_args_sp, bool stop_other_threads,
1399     Status &status) {
1400 
1401   ThreadPlanSP thread_plan_sp(new ScriptedThreadPlan(
1402       *this, class_name, StructuredDataImpl(extra_args_sp)));
1403   thread_plan_sp->SetStopOthers(stop_other_threads);
1404   status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
1405   return thread_plan_sp;
1406 }
1407 
1408 uint32_t Thread::GetIndexID() const { return m_index_id; }
1409 
1410 TargetSP Thread::CalculateTarget() {
1411   TargetSP target_sp;
1412   ProcessSP process_sp(GetProcess());
1413   if (process_sp)
1414     target_sp = process_sp->CalculateTarget();
1415   return target_sp;
1416 }
1417 
1418 ProcessSP Thread::CalculateProcess() { return GetProcess(); }
1419 
1420 ThreadSP Thread::CalculateThread() { return shared_from_this(); }
1421 
1422 StackFrameSP Thread::CalculateStackFrame() { return StackFrameSP(); }
1423 
1424 void Thread::CalculateExecutionContext(ExecutionContext &exe_ctx) {
1425   exe_ctx.SetContext(shared_from_this());
1426 }
1427 
1428 StackFrameListSP Thread::GetStackFrameList() {
1429   std::lock_guard<std::recursive_mutex> guard(m_frame_mutex);
1430 
1431   if (!m_curr_frames_sp)
1432     m_curr_frames_sp =
1433         std::make_shared<StackFrameList>(*this, m_prev_frames_sp, true);
1434 
1435   return m_curr_frames_sp;
1436 }
1437 
1438 std::optional<addr_t> Thread::GetPreviousFrameZeroPC() {
1439   return m_prev_framezero_pc;
1440 }
1441 
1442 void Thread::ClearStackFrames() {
1443   std::lock_guard<std::recursive_mutex> guard(m_frame_mutex);
1444 
1445   GetUnwinder().Clear();
1446   m_prev_framezero_pc.reset();
1447   if (RegisterContextSP reg_ctx_sp = GetRegisterContext())
1448     m_prev_framezero_pc = reg_ctx_sp->GetPC();
1449 
1450   // Only store away the old "reference" StackFrameList if we got all its
1451   // frames:
1452   // FIXME: At some point we can try to splice in the frames we have fetched
1453   // into the new frame as we make it, but let's not try that now.
1454   if (m_curr_frames_sp && m_curr_frames_sp->WereAllFramesFetched())
1455     m_prev_frames_sp.swap(m_curr_frames_sp);
1456   m_curr_frames_sp.reset();
1457 
1458   m_extended_info.reset();
1459   m_extended_info_fetched = false;
1460 }
1461 
1462 lldb::StackFrameSP Thread::GetFrameWithConcreteFrameIndex(uint32_t unwind_idx) {
1463   return GetStackFrameList()->GetFrameWithConcreteFrameIndex(unwind_idx);
1464 }
1465 
1466 Status Thread::ReturnFromFrameWithIndex(uint32_t frame_idx,
1467                                         lldb::ValueObjectSP return_value_sp,
1468                                         bool broadcast) {
1469   StackFrameSP frame_sp = GetStackFrameAtIndex(frame_idx);
1470   Status return_error;
1471 
1472   if (!frame_sp) {
1473     return_error = Status::FromErrorStringWithFormat(
1474         "Could not find frame with index %d in thread 0x%" PRIx64 ".",
1475         frame_idx, GetID());
1476   }
1477 
1478   return ReturnFromFrame(frame_sp, return_value_sp, broadcast);
1479 }
1480 
1481 Status Thread::ReturnFromFrame(lldb::StackFrameSP frame_sp,
1482                                lldb::ValueObjectSP return_value_sp,
1483                                bool broadcast) {
1484   Status return_error;
1485 
1486   if (!frame_sp) {
1487     return_error = Status::FromErrorString("Can't return to a null frame.");
1488     return return_error;
1489   }
1490 
1491   Thread *thread = frame_sp->GetThread().get();
1492   uint32_t older_frame_idx = frame_sp->GetFrameIndex() + 1;
1493   StackFrameSP older_frame_sp = thread->GetStackFrameAtIndex(older_frame_idx);
1494   if (!older_frame_sp) {
1495     return_error = Status::FromErrorString("No older frame to return to.");
1496     return return_error;
1497   }
1498 
1499   if (return_value_sp) {
1500     lldb::ABISP abi = thread->GetProcess()->GetABI();
1501     if (!abi) {
1502       return_error =
1503           Status::FromErrorString("Could not find ABI to set return value.");
1504       return return_error;
1505     }
1506     SymbolContext sc = frame_sp->GetSymbolContext(eSymbolContextFunction);
1507 
1508     // FIXME: ValueObject::Cast doesn't currently work correctly, at least not
1509     // for scalars.
1510     // Turn that back on when that works.
1511     if (/* DISABLES CODE */ (false) && sc.function != nullptr) {
1512       Type *function_type = sc.function->GetType();
1513       if (function_type) {
1514         CompilerType return_type =
1515             sc.function->GetCompilerType().GetFunctionReturnType();
1516         if (return_type) {
1517           StreamString s;
1518           return_type.DumpTypeDescription(&s);
1519           ValueObjectSP cast_value_sp = return_value_sp->Cast(return_type);
1520           if (cast_value_sp) {
1521             cast_value_sp->SetFormat(eFormatHex);
1522             return_value_sp = cast_value_sp;
1523           }
1524         }
1525       }
1526     }
1527 
1528     return_error = abi->SetReturnValueObject(older_frame_sp, return_value_sp);
1529     if (!return_error.Success())
1530       return return_error;
1531   }
1532 
1533   // Now write the return registers for the chosen frame: Note, we can't use
1534   // ReadAllRegisterValues->WriteAllRegisterValues, since the read & write cook
1535   // their data
1536 
1537   StackFrameSP youngest_frame_sp = thread->GetStackFrameAtIndex(0);
1538   if (youngest_frame_sp) {
1539     lldb::RegisterContextSP reg_ctx_sp(youngest_frame_sp->GetRegisterContext());
1540     if (reg_ctx_sp) {
1541       bool copy_success = reg_ctx_sp->CopyFromRegisterContext(
1542           older_frame_sp->GetRegisterContext());
1543       if (copy_success) {
1544         thread->DiscardThreadPlans(true);
1545         thread->ClearStackFrames();
1546         if (broadcast && EventTypeHasListeners(eBroadcastBitStackChanged)) {
1547           auto data_sp = std::make_shared<ThreadEventData>(shared_from_this());
1548           BroadcastEvent(eBroadcastBitStackChanged, data_sp);
1549         }
1550       } else {
1551         return_error =
1552             Status::FromErrorString("Could not reset register values.");
1553       }
1554     } else {
1555       return_error = Status::FromErrorString("Frame has no register context.");
1556     }
1557   } else {
1558     return_error = Status::FromErrorString("Returned past top frame.");
1559   }
1560   return return_error;
1561 }
1562 
1563 static void DumpAddressList(Stream &s, const std::vector<Address> &list,
1564                             ExecutionContextScope *exe_scope) {
1565   for (size_t n = 0; n < list.size(); n++) {
1566     s << "\t";
1567     list[n].Dump(&s, exe_scope, Address::DumpStyleResolvedDescription,
1568                  Address::DumpStyleSectionNameOffset);
1569     s << "\n";
1570   }
1571 }
1572 
1573 Status Thread::JumpToLine(const FileSpec &file, uint32_t line,
1574                           bool can_leave_function, std::string *warnings) {
1575   ExecutionContext exe_ctx(GetStackFrameAtIndex(0));
1576   Target *target = exe_ctx.GetTargetPtr();
1577   TargetSP target_sp = exe_ctx.GetTargetSP();
1578   RegisterContext *reg_ctx = exe_ctx.GetRegisterContext();
1579   StackFrame *frame = exe_ctx.GetFramePtr();
1580   const SymbolContext &sc = frame->GetSymbolContext(eSymbolContextFunction);
1581 
1582   // Find candidate locations.
1583   std::vector<Address> candidates, within_function, outside_function;
1584   target->GetImages().FindAddressesForLine(target_sp, file, line, sc.function,
1585                                            within_function, outside_function);
1586 
1587   // If possible, we try and stay within the current function. Within a
1588   // function, we accept multiple locations (optimized code may do this,
1589   // there's no solution here so we do the best we can). However if we're
1590   // trying to leave the function, we don't know how to pick the right
1591   // location, so if there's more than one then we bail.
1592   if (!within_function.empty())
1593     candidates = within_function;
1594   else if (outside_function.size() == 1 && can_leave_function)
1595     candidates = outside_function;
1596 
1597   // Check if we got anything.
1598   if (candidates.empty()) {
1599     if (outside_function.empty()) {
1600       return Status::FromErrorStringWithFormat(
1601           "Cannot locate an address for %s:%i.", file.GetFilename().AsCString(),
1602           line);
1603     } else if (outside_function.size() == 1) {
1604       return Status::FromErrorStringWithFormat(
1605           "%s:%i is outside the current function.",
1606           file.GetFilename().AsCString(), line);
1607     } else {
1608       StreamString sstr;
1609       DumpAddressList(sstr, outside_function, target);
1610       return Status::FromErrorStringWithFormat(
1611           "%s:%i has multiple candidate locations:\n%s",
1612           file.GetFilename().AsCString(), line, sstr.GetData());
1613     }
1614   }
1615 
1616   // Accept the first location, warn about any others.
1617   Address dest = candidates[0];
1618   if (warnings && candidates.size() > 1) {
1619     StreamString sstr;
1620     sstr.Printf("%s:%i appears multiple times in this function, selecting the "
1621                 "first location:\n",
1622                 file.GetFilename().AsCString(), line);
1623     DumpAddressList(sstr, candidates, target);
1624     *warnings = std::string(sstr.GetString());
1625   }
1626 
1627   if (!reg_ctx->SetPC(dest))
1628     return Status::FromErrorString("Cannot change PC to target address.");
1629 
1630   return Status();
1631 }
1632 
1633 bool Thread::DumpUsingFormat(Stream &strm, uint32_t frame_idx,
1634                              const FormatEntity::Entry *format) {
1635   ExecutionContext exe_ctx(shared_from_this());
1636   Process *process = exe_ctx.GetProcessPtr();
1637   if (!process || !format)
1638     return false;
1639 
1640   StackFrameSP frame_sp;
1641   SymbolContext frame_sc;
1642   if (frame_idx != LLDB_INVALID_FRAME_ID) {
1643     frame_sp = GetStackFrameAtIndex(frame_idx);
1644     if (frame_sp) {
1645       exe_ctx.SetFrameSP(frame_sp);
1646       frame_sc = frame_sp->GetSymbolContext(eSymbolContextEverything);
1647     }
1648   }
1649 
1650   return FormatEntity::Format(*format, strm, frame_sp ? &frame_sc : nullptr,
1651                               &exe_ctx, nullptr, nullptr, false, false);
1652 }
1653 
1654 void Thread::DumpUsingSettingsFormat(Stream &strm, uint32_t frame_idx,
1655                                      bool stop_format) {
1656   ExecutionContext exe_ctx(shared_from_this());
1657 
1658   const FormatEntity::Entry *thread_format;
1659   if (stop_format)
1660     thread_format = exe_ctx.GetTargetRef().GetDebugger().GetThreadStopFormat();
1661   else
1662     thread_format = exe_ctx.GetTargetRef().GetDebugger().GetThreadFormat();
1663 
1664   assert(thread_format);
1665 
1666   DumpUsingFormat(strm, frame_idx, thread_format);
1667 }
1668 
1669 void Thread::SettingsInitialize() {}
1670 
1671 void Thread::SettingsTerminate() {}
1672 
1673 lldb::addr_t Thread::GetThreadPointer() {
1674   if (m_reg_context_sp)
1675     return m_reg_context_sp->GetThreadPointer();
1676   return LLDB_INVALID_ADDRESS;
1677 }
1678 
1679 addr_t Thread::GetThreadLocalData(const ModuleSP module,
1680                                   lldb::addr_t tls_file_addr) {
1681   // The default implementation is to ask the dynamic loader for it. This can
1682   // be overridden for specific platforms.
1683   DynamicLoader *loader = GetProcess()->GetDynamicLoader();
1684   if (loader)
1685     return loader->GetThreadLocalData(module, shared_from_this(),
1686                                       tls_file_addr);
1687   else
1688     return LLDB_INVALID_ADDRESS;
1689 }
1690 
1691 bool Thread::SafeToCallFunctions() {
1692   Process *process = GetProcess().get();
1693   if (process) {
1694     DynamicLoader *loader = GetProcess()->GetDynamicLoader();
1695     if (loader && loader->IsFullyInitialized() == false)
1696       return false;
1697 
1698     SystemRuntime *runtime = process->GetSystemRuntime();
1699     if (runtime) {
1700       return runtime->SafeToCallFunctionsOnThisThread(shared_from_this());
1701     }
1702   }
1703   return true;
1704 }
1705 
1706 lldb::StackFrameSP
1707 Thread::GetStackFrameSPForStackFramePtr(StackFrame *stack_frame_ptr) {
1708   return GetStackFrameList()->GetStackFrameSPForStackFramePtr(stack_frame_ptr);
1709 }
1710 
1711 std::string Thread::StopReasonAsString(lldb::StopReason reason) {
1712   switch (reason) {
1713   case eStopReasonInvalid:
1714     return "invalid";
1715   case eStopReasonNone:
1716     return "none";
1717   case eStopReasonTrace:
1718     return "trace";
1719   case eStopReasonBreakpoint:
1720     return "breakpoint";
1721   case eStopReasonWatchpoint:
1722     return "watchpoint";
1723   case eStopReasonSignal:
1724     return "signal";
1725   case eStopReasonException:
1726     return "exception";
1727   case eStopReasonExec:
1728     return "exec";
1729   case eStopReasonFork:
1730     return "fork";
1731   case eStopReasonVFork:
1732     return "vfork";
1733   case eStopReasonVForkDone:
1734     return "vfork done";
1735   case eStopReasonPlanComplete:
1736     return "plan complete";
1737   case eStopReasonThreadExiting:
1738     return "thread exiting";
1739   case eStopReasonInstrumentation:
1740     return "instrumentation break";
1741   case eStopReasonProcessorTrace:
1742     return "processor trace";
1743   case eStopReasonInterrupt:
1744     return "async interrupt";
1745   }
1746 
1747   return "StopReason = " + std::to_string(reason);
1748 }
1749 
1750 std::string Thread::RunModeAsString(lldb::RunMode mode) {
1751   switch (mode) {
1752   case eOnlyThisThread:
1753     return "only this thread";
1754   case eAllThreads:
1755     return "all threads";
1756   case eOnlyDuringStepping:
1757     return "only during stepping";
1758   }
1759 
1760   return "RunMode = " + std::to_string(mode);
1761 }
1762 
1763 size_t Thread::GetStatus(Stream &strm, uint32_t start_frame,
1764                          uint32_t num_frames, uint32_t num_frames_with_source,
1765                          bool stop_format, bool show_hidden, bool only_stacks) {
1766 
1767   if (!only_stacks) {
1768     ExecutionContext exe_ctx(shared_from_this());
1769     Target *target = exe_ctx.GetTargetPtr();
1770     Process *process = exe_ctx.GetProcessPtr();
1771     strm.Indent();
1772     bool is_selected = false;
1773     if (process) {
1774       if (process->GetThreadList().GetSelectedThread().get() == this)
1775         is_selected = true;
1776     }
1777     strm.Printf("%c ", is_selected ? '*' : ' ');
1778     if (target && target->GetDebugger().GetUseExternalEditor()) {
1779       StackFrameSP frame_sp = GetStackFrameAtIndex(start_frame);
1780       if (frame_sp) {
1781         SymbolContext frame_sc(
1782             frame_sp->GetSymbolContext(eSymbolContextLineEntry));
1783         if (frame_sc.line_entry.line != 0 && frame_sc.line_entry.GetFile()) {
1784           if (llvm::Error e = Host::OpenFileInExternalEditor(
1785                   target->GetDebugger().GetExternalEditor(),
1786                   frame_sc.line_entry.GetFile(), frame_sc.line_entry.line)) {
1787             LLDB_LOG_ERROR(GetLog(LLDBLog::Host), std::move(e),
1788                            "OpenFileInExternalEditor failed: {0}");
1789           }
1790         }
1791       }
1792     }
1793 
1794     DumpUsingSettingsFormat(strm, start_frame, stop_format);
1795   }
1796 
1797   size_t num_frames_shown = 0;
1798   if (num_frames > 0) {
1799     strm.IndentMore();
1800 
1801     const bool show_frame_info = true;
1802     const bool show_frame_unique = only_stacks;
1803     const char *selected_frame_marker = nullptr;
1804     if (num_frames == 1 || only_stacks ||
1805         (GetID() != GetProcess()->GetThreadList().GetSelectedThread()->GetID()))
1806       strm.IndentMore();
1807     else
1808       selected_frame_marker = "* ";
1809 
1810     num_frames_shown = GetStackFrameList()->GetStatus(
1811         strm, start_frame, num_frames, show_frame_info, num_frames_with_source,
1812         show_frame_unique, show_hidden, selected_frame_marker);
1813     if (num_frames == 1)
1814       strm.IndentLess();
1815     strm.IndentLess();
1816   }
1817   return num_frames_shown;
1818 }
1819 
1820 bool Thread::GetDescription(Stream &strm, lldb::DescriptionLevel level,
1821                             bool print_json_thread, bool print_json_stopinfo) {
1822   const bool stop_format = false;
1823   DumpUsingSettingsFormat(strm, 0, stop_format);
1824   strm.Printf("\n");
1825 
1826   StructuredData::ObjectSP thread_info = GetExtendedInfo();
1827 
1828   if (print_json_thread || print_json_stopinfo) {
1829     if (thread_info && print_json_thread) {
1830       thread_info->Dump(strm);
1831       strm.Printf("\n");
1832     }
1833 
1834     if (print_json_stopinfo && m_stop_info_sp) {
1835       StructuredData::ObjectSP stop_info = m_stop_info_sp->GetExtendedInfo();
1836       if (stop_info) {
1837         stop_info->Dump(strm);
1838         strm.Printf("\n");
1839       }
1840     }
1841 
1842     return true;
1843   }
1844 
1845   if (thread_info) {
1846     StructuredData::ObjectSP activity =
1847         thread_info->GetObjectForDotSeparatedPath("activity");
1848     StructuredData::ObjectSP breadcrumb =
1849         thread_info->GetObjectForDotSeparatedPath("breadcrumb");
1850     StructuredData::ObjectSP messages =
1851         thread_info->GetObjectForDotSeparatedPath("trace_messages");
1852 
1853     bool printed_activity = false;
1854     if (activity && activity->GetType() == eStructuredDataTypeDictionary) {
1855       StructuredData::Dictionary *activity_dict = activity->GetAsDictionary();
1856       StructuredData::ObjectSP id = activity_dict->GetValueForKey("id");
1857       StructuredData::ObjectSP name = activity_dict->GetValueForKey("name");
1858       if (name && name->GetType() == eStructuredDataTypeString && id &&
1859           id->GetType() == eStructuredDataTypeInteger) {
1860         strm.Format("  Activity '{0}', {1:x}\n",
1861                     name->GetAsString()->GetValue(),
1862                     id->GetUnsignedIntegerValue());
1863       }
1864       printed_activity = true;
1865     }
1866     bool printed_breadcrumb = false;
1867     if (breadcrumb && breadcrumb->GetType() == eStructuredDataTypeDictionary) {
1868       if (printed_activity)
1869         strm.Printf("\n");
1870       StructuredData::Dictionary *breadcrumb_dict =
1871           breadcrumb->GetAsDictionary();
1872       StructuredData::ObjectSP breadcrumb_text =
1873           breadcrumb_dict->GetValueForKey("name");
1874       if (breadcrumb_text &&
1875           breadcrumb_text->GetType() == eStructuredDataTypeString) {
1876         strm.Format("  Current Breadcrumb: {0}\n",
1877                     breadcrumb_text->GetAsString()->GetValue());
1878       }
1879       printed_breadcrumb = true;
1880     }
1881     if (messages && messages->GetType() == eStructuredDataTypeArray) {
1882       if (printed_breadcrumb)
1883         strm.Printf("\n");
1884       StructuredData::Array *messages_array = messages->GetAsArray();
1885       const size_t msg_count = messages_array->GetSize();
1886       if (msg_count > 0) {
1887         strm.Printf("  %zu trace messages:\n", msg_count);
1888         for (size_t i = 0; i < msg_count; i++) {
1889           StructuredData::ObjectSP message = messages_array->GetItemAtIndex(i);
1890           if (message && message->GetType() == eStructuredDataTypeDictionary) {
1891             StructuredData::Dictionary *message_dict =
1892                 message->GetAsDictionary();
1893             StructuredData::ObjectSP message_text =
1894                 message_dict->GetValueForKey("message");
1895             if (message_text &&
1896                 message_text->GetType() == eStructuredDataTypeString) {
1897               strm.Format("    {0}\n", message_text->GetAsString()->GetValue());
1898             }
1899           }
1900         }
1901       }
1902     }
1903   }
1904 
1905   return true;
1906 }
1907 
1908 size_t Thread::GetStackFrameStatus(Stream &strm, uint32_t first_frame,
1909                                    uint32_t num_frames, bool show_frame_info,
1910                                    uint32_t num_frames_with_source,
1911                                    bool show_hidden) {
1912   return GetStackFrameList()->GetStatus(strm, first_frame, num_frames,
1913                                         show_frame_info, num_frames_with_source,
1914                                         /*show_unique*/ false, show_hidden);
1915 }
1916 
1917 Unwind &Thread::GetUnwinder() {
1918   if (!m_unwinder_up)
1919     m_unwinder_up = std::make_unique<UnwindLLDB>(*this);
1920   return *m_unwinder_up;
1921 }
1922 
1923 void Thread::Flush() {
1924   ClearStackFrames();
1925   m_reg_context_sp.reset();
1926 }
1927 
1928 bool Thread::IsStillAtLastBreakpointHit() {
1929   // If we are currently stopped at a breakpoint, always return that stopinfo
1930   // and don't reset it. This allows threads to maintain their breakpoint
1931   // stopinfo, such as when thread-stepping in multithreaded programs.
1932   if (m_stop_info_sp) {
1933     StopReason stop_reason = m_stop_info_sp->GetStopReason();
1934     if (stop_reason == lldb::eStopReasonBreakpoint) {
1935       uint64_t value = m_stop_info_sp->GetValue();
1936       lldb::RegisterContextSP reg_ctx_sp(GetRegisterContext());
1937       if (reg_ctx_sp) {
1938         lldb::addr_t pc = reg_ctx_sp->GetPC();
1939         BreakpointSiteSP bp_site_sp =
1940             GetProcess()->GetBreakpointSiteList().FindByAddress(pc);
1941         if (bp_site_sp && static_cast<break_id_t>(value) == bp_site_sp->GetID())
1942           return true;
1943       }
1944     }
1945   }
1946   return false;
1947 }
1948 
1949 Status Thread::StepIn(bool source_step,
1950                       LazyBool step_in_avoids_code_without_debug_info,
1951                       LazyBool step_out_avoids_code_without_debug_info)
1952 
1953 {
1954   Status error;
1955   Process *process = GetProcess().get();
1956   if (StateIsStoppedState(process->GetState(), true)) {
1957     StackFrameSP frame_sp = GetStackFrameAtIndex(0);
1958     ThreadPlanSP new_plan_sp;
1959     const lldb::RunMode run_mode = eOnlyThisThread;
1960     const bool abort_other_plans = false;
1961 
1962     if (source_step && frame_sp && frame_sp->HasDebugInformation()) {
1963       SymbolContext sc(frame_sp->GetSymbolContext(eSymbolContextEverything));
1964       new_plan_sp = QueueThreadPlanForStepInRange(
1965           abort_other_plans, sc.line_entry, sc, nullptr, run_mode, error,
1966           step_in_avoids_code_without_debug_info,
1967           step_out_avoids_code_without_debug_info);
1968     } else {
1969       new_plan_sp = QueueThreadPlanForStepSingleInstruction(
1970           false, abort_other_plans, run_mode, error);
1971     }
1972 
1973     new_plan_sp->SetIsControllingPlan(true);
1974     new_plan_sp->SetOkayToDiscard(false);
1975 
1976     // Why do we need to set the current thread by ID here???
1977     process->GetThreadList().SetSelectedThreadByID(GetID());
1978     error = process->Resume();
1979   } else {
1980     error = Status::FromErrorString("process not stopped");
1981   }
1982   return error;
1983 }
1984 
1985 Status Thread::StepOver(bool source_step,
1986                         LazyBool step_out_avoids_code_without_debug_info) {
1987   Status error;
1988   Process *process = GetProcess().get();
1989   if (StateIsStoppedState(process->GetState(), true)) {
1990     StackFrameSP frame_sp = GetStackFrameAtIndex(0);
1991     ThreadPlanSP new_plan_sp;
1992 
1993     const lldb::RunMode run_mode = eOnlyThisThread;
1994     const bool abort_other_plans = false;
1995 
1996     if (source_step && frame_sp && frame_sp->HasDebugInformation()) {
1997       SymbolContext sc(frame_sp->GetSymbolContext(eSymbolContextEverything));
1998       new_plan_sp = QueueThreadPlanForStepOverRange(
1999           abort_other_plans, sc.line_entry, sc, run_mode, error,
2000           step_out_avoids_code_without_debug_info);
2001     } else {
2002       new_plan_sp = QueueThreadPlanForStepSingleInstruction(
2003           true, abort_other_plans, run_mode, error);
2004     }
2005 
2006     new_plan_sp->SetIsControllingPlan(true);
2007     new_plan_sp->SetOkayToDiscard(false);
2008 
2009     // Why do we need to set the current thread by ID here???
2010     process->GetThreadList().SetSelectedThreadByID(GetID());
2011     error = process->Resume();
2012   } else {
2013     error = Status::FromErrorString("process not stopped");
2014   }
2015   return error;
2016 }
2017 
2018 Status Thread::StepOut(uint32_t frame_idx) {
2019   Status error;
2020   Process *process = GetProcess().get();
2021   if (StateIsStoppedState(process->GetState(), true)) {
2022     const bool first_instruction = false;
2023     const bool stop_other_threads = false;
2024     const bool abort_other_plans = false;
2025 
2026     ThreadPlanSP new_plan_sp(QueueThreadPlanForStepOut(
2027         abort_other_plans, nullptr, first_instruction, stop_other_threads,
2028         eVoteYes, eVoteNoOpinion, frame_idx, error));
2029 
2030     new_plan_sp->SetIsControllingPlan(true);
2031     new_plan_sp->SetOkayToDiscard(false);
2032 
2033     // Why do we need to set the current thread by ID here???
2034     process->GetThreadList().SetSelectedThreadByID(GetID());
2035     error = process->Resume();
2036   } else {
2037     error = Status::FromErrorString("process not stopped");
2038   }
2039   return error;
2040 }
2041 
2042 ValueObjectSP Thread::GetCurrentException() {
2043   if (auto frame_sp = GetStackFrameAtIndex(0))
2044     if (auto recognized_frame = frame_sp->GetRecognizedFrame())
2045       if (auto e = recognized_frame->GetExceptionObject())
2046         return e;
2047 
2048   // NOTE: Even though this behavior is generalized, only ObjC is actually
2049   // supported at the moment.
2050   for (LanguageRuntime *runtime : GetProcess()->GetLanguageRuntimes()) {
2051     if (auto e = runtime->GetExceptionObjectForThread(shared_from_this()))
2052       return e;
2053   }
2054 
2055   return ValueObjectSP();
2056 }
2057 
2058 ThreadSP Thread::GetCurrentExceptionBacktrace() {
2059   ValueObjectSP exception = GetCurrentException();
2060   if (!exception)
2061     return ThreadSP();
2062 
2063   // NOTE: Even though this behavior is generalized, only ObjC is actually
2064   // supported at the moment.
2065   for (LanguageRuntime *runtime : GetProcess()->GetLanguageRuntimes()) {
2066     if (auto bt = runtime->GetBacktraceThreadFromException(exception))
2067       return bt;
2068   }
2069 
2070   return ThreadSP();
2071 }
2072 
2073 lldb::ValueObjectSP Thread::GetSiginfoValue() {
2074   ProcessSP process_sp = GetProcess();
2075   assert(process_sp);
2076   Target &target = process_sp->GetTarget();
2077   PlatformSP platform_sp = target.GetPlatform();
2078   assert(platform_sp);
2079   ArchSpec arch = target.GetArchitecture();
2080 
2081   CompilerType type = platform_sp->GetSiginfoType(arch.GetTriple());
2082   if (!type.IsValid())
2083     return ValueObjectConstResult::Create(
2084         &target, Status::FromErrorString("no siginfo_t for the platform"));
2085 
2086   std::optional<uint64_t> type_size = type.GetByteSize(nullptr);
2087   assert(type_size);
2088   llvm::Expected<std::unique_ptr<llvm::MemoryBuffer>> data =
2089       GetSiginfo(*type_size);
2090   if (!data)
2091     return ValueObjectConstResult::Create(&target,
2092                                           Status::FromError(data.takeError()));
2093 
2094   DataExtractor data_extractor{data.get()->getBufferStart(), data.get()->getBufferSize(),
2095     process_sp->GetByteOrder(), arch.GetAddressByteSize()};
2096   return ValueObjectConstResult::Create(&target, type, ConstString("__lldb_siginfo"), data_extractor);
2097 }
2098