contrib/llvm/tools/lldb/source/Target/Thread.cpp

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