Import LLVM 10.0.0 release including clang, lld and lldb.

ok hackroom
tested by plenty

1 files changed, 2225 insertions, 0 deletions

diff --git a/gnu/llvm/lldb/source/Target/Thread.cpp b/gnu/llvm/lldb/source/Target/Thread.cpp
new file mode 100644
index 00000000000..e12b9050110
--- /dev/null
+++ b/gnu/llvm/lldb/source/Target/Thread.cpp
@@ -0,0 +1,2225 @@
+//===-- Thread.cpp ----------------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "lldb/Target/Thread.h"
+#include "Plugins/Process/Utility/UnwindLLDB.h"
+#include "Plugins/Process/Utility/UnwindMacOSXFrameBackchain.h"
+#include "lldb/Breakpoint/BreakpointLocation.h"
+#include "lldb/Core/Debugger.h"
+#include "lldb/Core/FormatEntity.h"
+#include "lldb/Core/Module.h"
+#include "lldb/Core/StructuredDataImpl.h"
+#include "lldb/Core/ValueObject.h"
+#include "lldb/Host/Host.h"
+#include "lldb/Interpreter/OptionValueFileSpecList.h"
+#include "lldb/Interpreter/OptionValueProperties.h"
+#include "lldb/Interpreter/Property.h"
+#include "lldb/Symbol/Function.h"
+#include "lldb/Target/ABI.h"
+#include "lldb/Target/DynamicLoader.h"
+#include "lldb/Target/ExecutionContext.h"
+#include "lldb/Target/LanguageRuntime.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Target/RegisterContext.h"
+#include "lldb/Target/StackFrameRecognizer.h"
+#include "lldb/Target/StopInfo.h"
+#include "lldb/Target/SystemRuntime.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Target/ThreadPlan.h"
+#include "lldb/Target/ThreadPlanBase.h"
+#include "lldb/Target/ThreadPlanCallFunction.h"
+#include "lldb/Target/ThreadPlanPython.h"
+#include "lldb/Target/ThreadPlanRunToAddress.h"
+#include "lldb/Target/ThreadPlanStepInRange.h"
+#include "lldb/Target/ThreadPlanStepInstruction.h"
+#include "lldb/Target/ThreadPlanStepOut.h"
+#include "lldb/Target/ThreadPlanStepOverBreakpoint.h"
+#include "lldb/Target/ThreadPlanStepOverRange.h"
+#include "lldb/Target/ThreadPlanStepThrough.h"
+#include "lldb/Target/ThreadPlanStepUntil.h"
+#include "lldb/Target/ThreadSpec.h"
+#include "lldb/Target/Unwind.h"
+#include "lldb/Utility/Log.h"
+#include "lldb/Utility/RegularExpression.h"
+#include "lldb/Utility/State.h"
+#include "lldb/Utility/Stream.h"
+#include "lldb/Utility/StreamString.h"
+#include "lldb/lldb-enumerations.h"
+
+#include <memory>
+
+using namespace lldb;
+using namespace lldb_private;
+
+const ThreadPropertiesSP &Thread::GetGlobalProperties() {
+  // NOTE: intentional leak so we don't crash if global destructor chain gets
+  // called as other threads still use the result of this function
+  static ThreadPropertiesSP *g_settings_sp_ptr =
+      new ThreadPropertiesSP(new ThreadProperties(true));
+  return *g_settings_sp_ptr;
+}
+
+#define LLDB_PROPERTIES_thread
+#include "TargetProperties.inc"
+
+enum {
+#define LLDB_PROPERTIES_thread
+#include "TargetPropertiesEnum.inc"
+};
+
+class ThreadOptionValueProperties : public OptionValueProperties {
+public:
+  ThreadOptionValueProperties(ConstString name)
+      : OptionValueProperties(name) {}
+
+  // This constructor is used when creating ThreadOptionValueProperties when it
+  // is part of a new lldb_private::Thread instance. It will copy all current
+  // global property values as needed
+  ThreadOptionValueProperties(ThreadProperties *global_properties)
+      : OptionValueProperties(*global_properties->GetValueProperties()) {}
+
+  const Property *GetPropertyAtIndex(const ExecutionContext *exe_ctx,
+                                     bool will_modify,
+                                     uint32_t idx) const override {
+    // When getting the value for a key from the thread options, we will always
+    // try and grab the setting from the current thread if there is one. Else
+    // we just use the one from this instance.
+    if (exe_ctx) {
+      Thread *thread = exe_ctx->GetThreadPtr();
+      if (thread) {
+        ThreadOptionValueProperties *instance_properties =
+            static_cast<ThreadOptionValueProperties *>(
+                thread->GetValueProperties().get());
+        if (this != instance_properties)
+          return instance_properties->ProtectedGetPropertyAtIndex(idx);
+      }
+    }
+    return ProtectedGetPropertyAtIndex(idx);
+  }
+};
+
+ThreadProperties::ThreadProperties(bool is_global) : Properties() {
+  if (is_global) {
+    m_collection_sp =
+        std::make_shared<ThreadOptionValueProperties>(ConstString("thread"));
+    m_collection_sp->Initialize(g_thread_properties);
+  } else
+    m_collection_sp = std::make_shared<ThreadOptionValueProperties>(
+        Thread::GetGlobalProperties().get());
+}
+
+ThreadProperties::~ThreadProperties() = default;
+
+const RegularExpression *ThreadProperties::GetSymbolsToAvoidRegexp() {
+  const uint32_t idx = ePropertyStepAvoidRegex;
+  return m_collection_sp->GetPropertyAtIndexAsOptionValueRegex(nullptr, idx);
+}
+
+FileSpecList ThreadProperties::GetLibrariesToAvoid() const {
+  const uint32_t idx = ePropertyStepAvoidLibraries;
+  const OptionValueFileSpecList *option_value =
+      m_collection_sp->GetPropertyAtIndexAsOptionValueFileSpecList(nullptr,
+                                                                   false, idx);
+  assert(option_value);
+  return option_value->GetCurrentValue();
+}
+
+bool ThreadProperties::GetTraceEnabledState() const {
+  const uint32_t idx = ePropertyEnableThreadTrace;
+  return m_collection_sp->GetPropertyAtIndexAsBoolean(
+      nullptr, idx, g_thread_properties[idx].default_uint_value != 0);
+}
+
+bool ThreadProperties::GetStepInAvoidsNoDebug() const {
+  const uint32_t idx = ePropertyStepInAvoidsNoDebug;
+  return m_collection_sp->GetPropertyAtIndexAsBoolean(
+      nullptr, idx, g_thread_properties[idx].default_uint_value != 0);
+}
+
+bool ThreadProperties::GetStepOutAvoidsNoDebug() const {
+  const uint32_t idx = ePropertyStepOutAvoidsNoDebug;
+  return m_collection_sp->GetPropertyAtIndexAsBoolean(
+      nullptr, idx, g_thread_properties[idx].default_uint_value != 0);
+}
+
+uint64_t ThreadProperties::GetMaxBacktraceDepth() const {
+  const uint32_t idx = ePropertyMaxBacktraceDepth;
+  return m_collection_sp->GetPropertyAtIndexAsUInt64(
+      nullptr, idx, g_thread_properties[idx].default_uint_value != 0);
+}
+
+// Thread Event Data
+
+ConstString Thread::ThreadEventData::GetFlavorString() {
+  static ConstString g_flavor("Thread::ThreadEventData");
+  return g_flavor;
+}
+
+Thread::ThreadEventData::ThreadEventData(const lldb::ThreadSP thread_sp)
+    : m_thread_sp(thread_sp), m_stack_id() {}
+
+Thread::ThreadEventData::ThreadEventData(const lldb::ThreadSP thread_sp,
+                                         const StackID &stack_id)
+    : m_thread_sp(thread_sp), m_stack_id(stack_id) {}
+
+Thread::ThreadEventData::ThreadEventData() : m_thread_sp(), m_stack_id() {}
+
+Thread::ThreadEventData::~ThreadEventData() = default;
+
+void Thread::ThreadEventData::Dump(Stream *s) const {}
+
+const Thread::ThreadEventData *
+Thread::ThreadEventData::GetEventDataFromEvent(const Event *event_ptr) {
+  if (event_ptr) {
+    const EventData *event_data = event_ptr->GetData();
+    if (event_data &&
+        event_data->GetFlavor() == ThreadEventData::GetFlavorString())
+      return static_cast<const ThreadEventData *>(event_ptr->GetData());
+  }
+  return nullptr;
+}
+
+ThreadSP Thread::ThreadEventData::GetThreadFromEvent(const Event *event_ptr) {
+  ThreadSP thread_sp;
+  const ThreadEventData *event_data = GetEventDataFromEvent(event_ptr);
+  if (event_data)
+    thread_sp = event_data->GetThread();
+  return thread_sp;
+}
+
+StackID Thread::ThreadEventData::GetStackIDFromEvent(const Event *event_ptr) {
+  StackID stack_id;
+  const ThreadEventData *event_data = GetEventDataFromEvent(event_ptr);
+  if (event_data)
+    stack_id = event_data->GetStackID();
+  return stack_id;
+}
+
+StackFrameSP
+Thread::ThreadEventData::GetStackFrameFromEvent(const Event *event_ptr) {
+  const ThreadEventData *event_data = GetEventDataFromEvent(event_ptr);
+  StackFrameSP frame_sp;
+  if (event_data) {
+    ThreadSP thread_sp = event_data->GetThread();
+    if (thread_sp) {
+      frame_sp = thread_sp->GetStackFrameList()->GetFrameWithStackID(
+          event_data->GetStackID());
+    }
+  }
+  return frame_sp;
+}
+
+// Thread class
+
+ConstString &Thread::GetStaticBroadcasterClass() {
+  static ConstString class_name("lldb.thread");
+  return class_name;
+}
+
+Thread::Thread(Process &process, lldb::tid_t tid, bool use_invalid_index_id)
+    : ThreadProperties(false), UserID(tid),
+      Broadcaster(process.GetTarget().GetDebugger().GetBroadcasterManager(),
+                  Thread::GetStaticBroadcasterClass().AsCString()),
+      m_process_wp(process.shared_from_this()), m_stop_info_sp(),
+      m_stop_info_stop_id(0), m_stop_info_override_stop_id(0),
+      m_index_id(use_invalid_index_id ? LLDB_INVALID_INDEX32
+                                      : process.GetNextThreadIndexID(tid)),
+      m_reg_context_sp(), m_state(eStateUnloaded), m_state_mutex(),
+      m_plan_stack(), m_completed_plan_stack(), m_frame_mutex(),
+      m_curr_frames_sp(), m_prev_frames_sp(),
+      m_resume_signal(LLDB_INVALID_SIGNAL_NUMBER),
+      m_resume_state(eStateRunning), m_temporary_resume_state(eStateRunning),
+      m_unwinder_up(), m_destroy_called(false),
+      m_override_should_notify(eLazyBoolCalculate),
+      m_extended_info_fetched(false), m_extended_info() {
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_OBJECT));
+  LLDB_LOGF(log, "%p Thread::Thread(tid = 0x%4.4" PRIx64 ")",
+            static_cast<void *>(this), GetID());
+
+  CheckInWithManager();
+
+  QueueFundamentalPlan(true);
+}
+
+Thread::~Thread() {
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_OBJECT));
+  LLDB_LOGF(log, "%p Thread::~Thread(tid = 0x%4.4" PRIx64 ")",
+            static_cast<void *>(this), GetID());
+  /// If you hit this assert, it means your derived class forgot to call
+  /// DoDestroy in its destructor.
+  assert(m_destroy_called);
+}
+
+void Thread::DestroyThread() {
+  // Tell any plans on the plan stacks that the thread is being destroyed since
+  // any plans that have a thread go away in the middle of might need to do
+  // cleanup, or in some cases NOT do cleanup...
+  for (auto plan : m_plan_stack)
+    plan->ThreadDestroyed();
+
+  for (auto plan : m_discarded_plan_stack)
+    plan->ThreadDestroyed();
+
+  for (auto plan : m_completed_plan_stack)
+    plan->ThreadDestroyed();
+
+  m_destroy_called = true;
+  m_plan_stack.clear();
+  m_discarded_plan_stack.clear();
+  m_completed_plan_stack.clear();
+
+  // Push a ThreadPlanNull on the plan stack.  That way we can continue
+  // assuming that the plan stack is never empty, but if somebody errantly asks
+  // questions of a destroyed thread without checking first whether it is
+  // destroyed, they won't crash.
+  ThreadPlanSP null_plan_sp(new ThreadPlanNull(*this));
+  m_plan_stack.push_back(null_plan_sp);
+
+  m_stop_info_sp.reset();
+  m_reg_context_sp.reset();
+  m_unwinder_up.reset();
+  std::lock_guard<std::recursive_mutex> guard(m_frame_mutex);
+  m_curr_frames_sp.reset();
+  m_prev_frames_sp.reset();
+}
+
+void Thread::BroadcastSelectedFrameChange(StackID &new_frame_id) {
+  if (EventTypeHasListeners(eBroadcastBitSelectedFrameChanged))
+    BroadcastEvent(eBroadcastBitSelectedFrameChanged,
+                   new ThreadEventData(this->shared_from_this(), new_frame_id));
+}
+
+lldb::StackFrameSP Thread::GetSelectedFrame() {
+  StackFrameListSP stack_frame_list_sp(GetStackFrameList());
+  StackFrameSP frame_sp = stack_frame_list_sp->GetFrameAtIndex(
+      stack_frame_list_sp->GetSelectedFrameIndex());
+  FunctionOptimizationWarning(frame_sp.get());
+  return frame_sp;
+}
+
+uint32_t Thread::SetSelectedFrame(lldb_private::StackFrame *frame,
+                                  bool broadcast) {
+  uint32_t ret_value = GetStackFrameList()->SetSelectedFrame(frame);
+  if (broadcast)
+    BroadcastSelectedFrameChange(frame->GetStackID());
+  FunctionOptimizationWarning(frame);
+  return ret_value;
+}
+
+bool Thread::SetSelectedFrameByIndex(uint32_t frame_idx, bool broadcast) {
+  StackFrameSP frame_sp(GetStackFrameList()->GetFrameAtIndex(frame_idx));
+  if (frame_sp) {
+    GetStackFrameList()->SetSelectedFrame(frame_sp.get());
+    if (broadcast)
+      BroadcastSelectedFrameChange(frame_sp->GetStackID());
+    FunctionOptimizationWarning(frame_sp.get());
+    return true;
+  } else
+    return false;
+}
+
+bool Thread::SetSelectedFrameByIndexNoisily(uint32_t frame_idx,
+                                            Stream &output_stream) {
+  const bool broadcast = true;
+  bool success = SetSelectedFrameByIndex(frame_idx, broadcast);
+  if (success) {
+    StackFrameSP frame_sp = GetSelectedFrame();
+    if (frame_sp) {
+      bool already_shown = false;
+      SymbolContext frame_sc(
+          frame_sp->GetSymbolContext(eSymbolContextLineEntry));
+      if (GetProcess()->GetTarget().GetDebugger().GetUseExternalEditor() &&
+          frame_sc.line_entry.file && frame_sc.line_entry.line != 0) {
+        already_shown = Host::OpenFileInExternalEditor(
+            frame_sc.line_entry.file, frame_sc.line_entry.line);
+      }
+
+      bool show_frame_info = true;
+      bool show_source = !already_shown;
+      FunctionOptimizationWarning(frame_sp.get());
+      return frame_sp->GetStatus(output_stream, show_frame_info, show_source);
+    }
+    return false;
+  } else
+    return false;
+}
+
+void Thread::FunctionOptimizationWarning(StackFrame *frame) {
+  if (frame && frame->HasDebugInformation() &&
+      GetProcess()->GetWarningsOptimization()) {
+    SymbolContext sc =
+        frame->GetSymbolContext(eSymbolContextFunction | eSymbolContextModule);
+    GetProcess()->PrintWarningOptimization(sc);
+  }
+}
+
+lldb::StopInfoSP Thread::GetStopInfo() {
+  if (m_destroy_called)
+    return m_stop_info_sp;
+
+  ThreadPlanSP completed_plan_sp(GetCompletedPlan());
+  ProcessSP process_sp(GetProcess());
+  const uint32_t stop_id = process_sp ? process_sp->GetStopID() : UINT32_MAX;
+
+  // Here we select the stop info according to priorirty: - m_stop_info_sp (if
+  // not trace) - preset value - completed plan stop info - new value with plan
+  // from completed plan stack - m_stop_info_sp (trace stop reason is OK now) -
+  // ask GetPrivateStopInfo to set stop info
+
+  bool have_valid_stop_info = m_stop_info_sp &&
+      m_stop_info_sp ->IsValid() &&
+      m_stop_info_stop_id == stop_id;
+  bool have_valid_completed_plan = completed_plan_sp && completed_plan_sp->PlanSucceeded();
+  bool plan_failed = completed_plan_sp && !completed_plan_sp->PlanSucceeded();
+  bool plan_overrides_trace =
+    have_valid_stop_info && have_valid_completed_plan
+    && (m_stop_info_sp->GetStopReason() == eStopReasonTrace);
+
+  if (have_valid_stop_info && !plan_overrides_trace && !plan_failed) {
+    return m_stop_info_sp;
+  } else if (completed_plan_sp) {
+    return StopInfo::CreateStopReasonWithPlan(
+        completed_plan_sp, GetReturnValueObject(), GetExpressionVariable());
+  } else {
+    GetPrivateStopInfo();
+    return m_stop_info_sp;
+  }
+}
+
+void Thread::CalculatePublicStopInfo() {
+  ResetStopInfo();
+  SetStopInfo(GetStopInfo());
+}
+
+lldb::StopInfoSP Thread::GetPrivateStopInfo() {
+  if (m_destroy_called)
+    return m_stop_info_sp;
+
+  ProcessSP process_sp(GetProcess());
+  if (process_sp) {
+    const uint32_t process_stop_id = process_sp->GetStopID();
+    if (m_stop_info_stop_id != process_stop_id) {
+      if (m_stop_info_sp) {
+        if (m_stop_info_sp->IsValid() || IsStillAtLastBreakpointHit() ||
+            GetCurrentPlan()->IsVirtualStep())
+          SetStopInfo(m_stop_info_sp);
+        else
+          m_stop_info_sp.reset();
+      }
+
+      if (!m_stop_info_sp) {
+        if (!CalculateStopInfo())
+          SetStopInfo(StopInfoSP());
+      }
+    }
+
+    // The stop info can be manually set by calling Thread::SetStopInfo() prior
+    // to this function ever getting called, so we can't rely on
+    // "m_stop_info_stop_id != process_stop_id" as the condition for the if
+    // statement below, we must also check the stop info to see if we need to
+    // override it. See the header documentation in
+    // Process::GetStopInfoOverrideCallback() for more information on the stop
+    // info override callback.
+    if (m_stop_info_override_stop_id != process_stop_id) {
+      m_stop_info_override_stop_id = process_stop_id;
+      if (m_stop_info_sp) {
+        if (const Architecture *arch =
+                process_sp->GetTarget().GetArchitecturePlugin())
+          arch->OverrideStopInfo(*this);
+      }
+    }
+  }
+  return m_stop_info_sp;
+}
+
+lldb::StopReason Thread::GetStopReason() {
+  lldb::StopInfoSP stop_info_sp(GetStopInfo());
+  if (stop_info_sp)
+    return stop_info_sp->GetStopReason();
+  return eStopReasonNone;
+}
+
+bool Thread::StopInfoIsUpToDate() const {
+  ProcessSP process_sp(GetProcess());
+  if (process_sp)
+    return m_stop_info_stop_id == process_sp->GetStopID();
+  else
+    return true; // Process is no longer around so stop info is always up to
+                 // date...
+}
+
+void Thread::ResetStopInfo() {
+  if (m_stop_info_sp) {
+    m_stop_info_sp.reset();
+  }
+}
+
+void Thread::SetStopInfo(const lldb::StopInfoSP &stop_info_sp) {
+  m_stop_info_sp = stop_info_sp;
+  if (m_stop_info_sp) {
+    m_stop_info_sp->MakeStopInfoValid();
+    // If we are overriding the ShouldReportStop, do that here:
+    if (m_override_should_notify != eLazyBoolCalculate)
+      m_stop_info_sp->OverrideShouldNotify(m_override_should_notify ==
+                                           eLazyBoolYes);
+  }
+
+  ProcessSP process_sp(GetProcess());
+  if (process_sp)
+    m_stop_info_stop_id = process_sp->GetStopID();
+  else
+    m_stop_info_stop_id = UINT32_MAX;
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_THREAD));
+  LLDB_LOGF(log, "%p: tid = 0x%" PRIx64 ": stop info = %s (stop_id = %u)",
+            static_cast<void *>(this), GetID(),
+            stop_info_sp ? stop_info_sp->GetDescription() : "<NULL>",
+            m_stop_info_stop_id);
+}
+
+void Thread::SetShouldReportStop(Vote vote) {
+  if (vote == eVoteNoOpinion)
+    return;
+  else {
+    m_override_should_notify = (vote == eVoteYes ? eLazyBoolYes : eLazyBoolNo);
+    if (m_stop_info_sp)
+      m_stop_info_sp->OverrideShouldNotify(m_override_should_notify ==
+                                           eLazyBoolYes);
+  }
+}
+
+void Thread::SetStopInfoToNothing() {
+  // Note, we can't just NULL out the private reason, or the native thread
+  // implementation will try to go calculate it again.  For now, just set it to
+  // a Unix Signal with an invalid signal number.
+  SetStopInfo(
+      StopInfo::CreateStopReasonWithSignal(*this, LLDB_INVALID_SIGNAL_NUMBER));
+}
+
+bool Thread::ThreadStoppedForAReason(void) {
+  return (bool)GetPrivateStopInfo();
+}
+
+bool Thread::CheckpointThreadState(ThreadStateCheckpoint &saved_state) {
+  saved_state.register_backup_sp.reset();
+  lldb::StackFrameSP frame_sp(GetStackFrameAtIndex(0));
+  if (frame_sp) {
+    lldb::RegisterCheckpointSP reg_checkpoint_sp(
+        new RegisterCheckpoint(RegisterCheckpoint::Reason::eExpression));
+    if (reg_checkpoint_sp) {
+      lldb::RegisterContextSP reg_ctx_sp(frame_sp->GetRegisterContext());
+      if (reg_ctx_sp && reg_ctx_sp->ReadAllRegisterValues(*reg_checkpoint_sp))
+        saved_state.register_backup_sp = reg_checkpoint_sp;
+    }
+  }
+  if (!saved_state.register_backup_sp)
+    return false;
+
+  saved_state.stop_info_sp = GetStopInfo();
+  ProcessSP process_sp(GetProcess());
+  if (process_sp)
+    saved_state.orig_stop_id = process_sp->GetStopID();
+  saved_state.current_inlined_depth = GetCurrentInlinedDepth();
+  saved_state.m_completed_plan_stack = m_completed_plan_stack;
+
+  return true;
+}
+
+bool Thread::RestoreRegisterStateFromCheckpoint(
+    ThreadStateCheckpoint &saved_state) {
+  if (saved_state.register_backup_sp) {
+    lldb::StackFrameSP frame_sp(GetStackFrameAtIndex(0));
+    if (frame_sp) {
+      lldb::RegisterContextSP reg_ctx_sp(frame_sp->GetRegisterContext());
+      if (reg_ctx_sp) {
+        bool ret =
+            reg_ctx_sp->WriteAllRegisterValues(*saved_state.register_backup_sp);
+
+        // Clear out all stack frames as our world just changed.
+        ClearStackFrames();
+        reg_ctx_sp->InvalidateIfNeeded(true);
+        if (m_unwinder_up)
+          m_unwinder_up->Clear();
+        return ret;
+      }
+    }
+  }
+  return false;
+}
+
+bool Thread::RestoreThreadStateFromCheckpoint(
+    ThreadStateCheckpoint &saved_state) {
+  if (saved_state.stop_info_sp)
+    saved_state.stop_info_sp->MakeStopInfoValid();
+  SetStopInfo(saved_state.stop_info_sp);
+  GetStackFrameList()->SetCurrentInlinedDepth(
+      saved_state.current_inlined_depth);
+  m_completed_plan_stack = saved_state.m_completed_plan_stack;
+  return true;
+}
+
+StateType Thread::GetState() const {
+  // If any other threads access this we will need a mutex for it
+  std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
+  return m_state;
+}
+
+void Thread::SetState(StateType state) {
+  std::lock_guard<std::recursive_mutex> guard(m_state_mutex);
+  m_state = state;
+}
+
+void Thread::WillStop() {
+  ThreadPlan *current_plan = GetCurrentPlan();
+
+  // FIXME: I may decide to disallow threads with no plans.  In which
+  // case this should go to an assert.
+
+  if (!current_plan)
+    return;
+
+  current_plan->WillStop();
+}
+
+void Thread::SetupForResume() {
+  if (GetResumeState() != eStateSuspended) {
+    // If we're at a breakpoint push the step-over breakpoint plan.  Do this
+    // before telling the current plan it will resume, since we might change
+    // what the current plan is.
+
+    lldb::RegisterContextSP reg_ctx_sp(GetRegisterContext());
+    if (reg_ctx_sp) {
+      const addr_t thread_pc = reg_ctx_sp->GetPC();
+      BreakpointSiteSP bp_site_sp =
+          GetProcess()->GetBreakpointSiteList().FindByAddress(thread_pc);
+      if (bp_site_sp) {
+        // Note, don't assume there's a ThreadPlanStepOverBreakpoint, the
+        // target may not require anything special to step over a breakpoint.
+
+        ThreadPlan *cur_plan = GetCurrentPlan();
+
+        bool push_step_over_bp_plan = false;
+        if (cur_plan->GetKind() == ThreadPlan::eKindStepOverBreakpoint) {
+          ThreadPlanStepOverBreakpoint *bp_plan =
+              (ThreadPlanStepOverBreakpoint *)cur_plan;
+          if (bp_plan->GetBreakpointLoadAddress() != thread_pc)
+            push_step_over_bp_plan = true;
+        } else
+          push_step_over_bp_plan = true;
+
+        if (push_step_over_bp_plan) {
+          ThreadPlanSP step_bp_plan_sp(new ThreadPlanStepOverBreakpoint(*this));
+          if (step_bp_plan_sp) {
+            step_bp_plan_sp->SetPrivate(true);
+
+            if (GetCurrentPlan()->RunState() != eStateStepping) {
+              ThreadPlanStepOverBreakpoint *step_bp_plan =
+                  static_cast<ThreadPlanStepOverBreakpoint *>(
+                      step_bp_plan_sp.get());
+              step_bp_plan->SetAutoContinue(true);
+            }
+            QueueThreadPlan(step_bp_plan_sp, false);
+          }
+        }
+      }
+    }
+  }
+}
+
+bool Thread::ShouldResume(StateType resume_state) {
+  // At this point clear the completed plan stack.
+  m_completed_plan_stack.clear();
+  m_discarded_plan_stack.clear();
+  m_override_should_notify = eLazyBoolCalculate;
+
+  StateType prev_resume_state = GetTemporaryResumeState();
+
+  SetTemporaryResumeState(resume_state);
+
+  lldb::ThreadSP backing_thread_sp(GetBackingThread());
+  if (backing_thread_sp)
+    backing_thread_sp->SetTemporaryResumeState(resume_state);
+
+  // Make sure m_stop_info_sp is valid.  Don't do this for threads we suspended
+  // in the previous run.
+  if (prev_resume_state != eStateSuspended)
+    GetPrivateStopInfo();
+
+  // This is a little dubious, but we are trying to limit how often we actually
+  // fetch stop info from the target, 'cause that slows down single stepping.
+  // So assume that if we got to the point where we're about to resume, and we
+  // haven't yet had to fetch the stop reason, then it doesn't need to know
+  // about the fact that we are resuming...
+  const uint32_t process_stop_id = GetProcess()->GetStopID();
+  if (m_stop_info_stop_id == process_stop_id &&
+      (m_stop_info_sp && m_stop_info_sp->IsValid())) {
+    StopInfo *stop_info = GetPrivateStopInfo().get();
+    if (stop_info)
+      stop_info->WillResume(resume_state);
+  }
+
+  // Tell all the plans that we are about to resume in case they need to clear
+  // any state. We distinguish between the plan on the top of the stack and the
+  // lower plans in case a plan needs to do any special business before it
+  // runs.
+
+  bool need_to_resume = false;
+  ThreadPlan *plan_ptr = GetCurrentPlan();
+  if (plan_ptr) {
+    need_to_resume = plan_ptr->WillResume(resume_state, true);
+
+    while ((plan_ptr = GetPreviousPlan(plan_ptr)) != nullptr) {
+      plan_ptr->WillResume(resume_state, false);
+    }
+
+    // If the WillResume for the plan says we are faking a resume, then it will
+    // have set an appropriate stop info. In that case, don't reset it here.
+
+    if (need_to_resume && resume_state != eStateSuspended) {
+      m_stop_info_sp.reset();
+    }
+  }
+
+  if (need_to_resume) {
+    ClearStackFrames();
+    // Let Thread subclasses do any special work they need to prior to resuming
+    WillResume(resume_state);
+  }
+
+  return need_to_resume;
+}
+
+void Thread::DidResume() { SetResumeSignal(LLDB_INVALID_SIGNAL_NUMBER); }
+
+void Thread::DidStop() { SetState(eStateStopped); }
+
+bool Thread::ShouldStop(Event *event_ptr) {
+  ThreadPlan *current_plan = GetCurrentPlan();
+
+  bool should_stop = true;
+
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+
+  if (GetResumeState() == eStateSuspended) {
+    LLDB_LOGF(log,
+              "Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64
+              ", should_stop = 0 (ignore since thread was suspended)",
+              __FUNCTION__, GetID(), GetProtocolID());
+    return false;
+  }
+
+  if (GetTemporaryResumeState() == eStateSuspended) {
+    LLDB_LOGF(log,
+              "Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64
+              ", should_stop = 0 (ignore since thread was suspended)",
+              __FUNCTION__, GetID(), GetProtocolID());
+    return false;
+  }
+
+  // Based on the current thread plan and process stop info, check if this
+  // thread caused the process to stop. NOTE: this must take place before the
+  // plan is moved from the current plan stack to the completed plan stack.
+  if (!ThreadStoppedForAReason()) {
+    LLDB_LOGF(log,
+              "Thread::%s for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64
+              ", pc = 0x%16.16" PRIx64
+              ", should_stop = 0 (ignore since no stop reason)",
+              __FUNCTION__, GetID(), GetProtocolID(),
+              GetRegisterContext() ? GetRegisterContext()->GetPC()
+                                   : LLDB_INVALID_ADDRESS);
+    return false;
+  }
+
+  if (log) {
+    LLDB_LOGF(log,
+              "Thread::%s(%p) for tid = 0x%4.4" PRIx64 " 0x%4.4" PRIx64
+              ", pc = 0x%16.16" PRIx64,
+              __FUNCTION__, static_cast<void *>(this), GetID(), GetProtocolID(),
+              GetRegisterContext() ? GetRegisterContext()->GetPC()
+                                   : LLDB_INVALID_ADDRESS);
+    LLDB_LOGF(log, "^^^^^^^^ Thread::ShouldStop Begin ^^^^^^^^");
+    StreamString s;
+    s.IndentMore();
+    DumpThreadPlans(&s);
+    LLDB_LOGF(log, "Plan stack initial state:\n%s", s.GetData());
+  }
+
+  // The top most plan always gets to do the trace log...
+  current_plan->DoTraceLog();
+
+  // First query the stop info's ShouldStopSynchronous.  This handles
+  // "synchronous" stop reasons, for example the breakpoint command on internal
+  // breakpoints.  If a synchronous stop reason says we should not stop, then
+  // we don't have to do any more work on this stop.
+  StopInfoSP private_stop_info(GetPrivateStopInfo());
+  if (private_stop_info &&
+      !private_stop_info->ShouldStopSynchronous(event_ptr)) {
+    LLDB_LOGF(log, "StopInfo::ShouldStop async callback says we should not "
+                   "stop, returning ShouldStop of false.");
+    return false;
+  }
+
+  // If we've already been restarted, don't query the plans since the state
+  // they would examine is not current.
+  if (Process::ProcessEventData::GetRestartedFromEvent(event_ptr))
+    return false;
+
+  // Before the plans see the state of the world, calculate the current inlined
+  // depth.
+  GetStackFrameList()->CalculateCurrentInlinedDepth();
+
+  // If the base plan doesn't understand why we stopped, then we have to find a
+  // plan that does. If that plan is still working, then we don't need to do
+  // any more work.  If the plan that explains the stop is done, then we should
+  // pop all the plans below it, and pop it, and then let the plans above it
+  // decide whether they still need to do more work.
+
+  bool done_processing_current_plan = false;
+
+  if (!current_plan->PlanExplainsStop(event_ptr)) {
+    if (current_plan->TracerExplainsStop()) {
+      done_processing_current_plan = true;
+      should_stop = false;
+    } else {
+      // If the current plan doesn't explain the stop, then find one that does
+      // and let it handle the situation.
+      ThreadPlan *plan_ptr = current_plan;
+      while ((plan_ptr = GetPreviousPlan(plan_ptr)) != nullptr) {
+        if (plan_ptr->PlanExplainsStop(event_ptr)) {
+          should_stop = plan_ptr->ShouldStop(event_ptr);
+
+          // plan_ptr explains the stop, next check whether plan_ptr is done,
+          // if so, then we should take it and all the plans below it off the
+          // stack.
+
+          if (plan_ptr->MischiefManaged()) {
+            // We're going to pop the plans up to and including the plan that
+            // explains the stop.
+            ThreadPlan *prev_plan_ptr = GetPreviousPlan(plan_ptr);
+
+            do {
+              if (should_stop)
+                current_plan->WillStop();
+              PopPlan();
+            } while ((current_plan = GetCurrentPlan()) != prev_plan_ptr);
+            // Now, if the responsible plan was not "Okay to discard" then
+            // we're done, otherwise we forward this to the next plan in the
+            // stack below.
+            done_processing_current_plan =
+                (plan_ptr->IsMasterPlan() && !plan_ptr->OkayToDiscard());
+          } else
+            done_processing_current_plan = true;
+
+          break;
+        }
+      }
+    }
+  }
+
+  if (!done_processing_current_plan) {
+    bool over_ride_stop = current_plan->ShouldAutoContinue(event_ptr);
+
+    LLDB_LOGF(log, "Plan %s explains stop, auto-continue %i.",
+              current_plan->GetName(), over_ride_stop);
+
+    // We're starting from the base plan, so just let it decide;
+    if (PlanIsBasePlan(current_plan)) {
+      should_stop = current_plan->ShouldStop(event_ptr);
+      LLDB_LOGF(log, "Base plan says should stop: %i.", should_stop);
+    } else {
+      // Otherwise, don't let the base plan override what the other plans say
+      // to do, since presumably if there were other plans they would know what
+      // to do...
+      while (true) {
+        if (PlanIsBasePlan(current_plan))
+          break;
+
+        should_stop = current_plan->ShouldStop(event_ptr);
+        LLDB_LOGF(log, "Plan %s should stop: %d.", current_plan->GetName(),
+                  should_stop);
+        if (current_plan->MischiefManaged()) {
+          if (should_stop)
+            current_plan->WillStop();
+
+          // If a Master Plan wants to stop, and wants to stick on the stack,
+          // we let it. Otherwise, see if the plan's parent wants to stop.
+
+          if (should_stop && current_plan->IsMasterPlan() &&
+              !current_plan->OkayToDiscard()) {
+            PopPlan();
+            break;
+          } else {
+            PopPlan();
+
+            current_plan = GetCurrentPlan();
+            if (current_plan == nullptr) {
+              break;
+            }
+          }
+        } else {
+          break;
+        }
+      }
+    }
+
+    if (over_ride_stop)
+      should_stop = false;
+  }
+
+  // One other potential problem is that we set up a master plan, then stop in
+  // before it is complete - for instance by hitting a breakpoint during a
+  // step-over - then do some step/finish/etc operations that wind up past the
+  // end point condition of the initial plan.  We don't want to strand the
+  // original plan on the stack, This code clears stale plans off the stack.
+
+  if (should_stop) {
+    ThreadPlan *plan_ptr = GetCurrentPlan();
+
+    // Discard the stale plans and all plans below them in the stack, plus move
+    // the completed plans to the completed plan stack
+    while (!PlanIsBasePlan(plan_ptr)) {
+      bool stale = plan_ptr->IsPlanStale();
+      ThreadPlan *examined_plan = plan_ptr;
+      plan_ptr = GetPreviousPlan(examined_plan);
+
+      if (stale) {
+        LLDB_LOGF(
+            log,
+            "Plan %s being discarded in cleanup, it says it is already done.",
+            examined_plan->GetName());
+        while (GetCurrentPlan() != examined_plan) {
+          DiscardPlan();
+        }
+        if (examined_plan->IsPlanComplete()) {
+          // plan is complete but does not explain the stop (example: step to a
+          // line with breakpoint), let us move the plan to
+          // completed_plan_stack anyway
+          PopPlan();
+        } else
+          DiscardPlan();
+      }
+    }
+  }
+
+  if (log) {
+    StreamString s;
+    s.IndentMore();
+    DumpThreadPlans(&s);
+    LLDB_LOGF(log, "Plan stack final state:\n%s", s.GetData());
+    LLDB_LOGF(log, "vvvvvvvv Thread::ShouldStop End (returning %i) vvvvvvvv",
+              should_stop);
+  }
+  return should_stop;
+}
+
+Vote Thread::ShouldReportStop(Event *event_ptr) {
+  StateType thread_state = GetResumeState();
+  StateType temp_thread_state = GetTemporaryResumeState();
+
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+
+  if (thread_state == eStateSuspended || thread_state == eStateInvalid) {
+    LLDB_LOGF(log,
+              "Thread::ShouldReportStop() tid = 0x%4.4" PRIx64
+              ": returning vote %i (state was suspended or invalid)",
+              GetID(), eVoteNoOpinion);
+    return eVoteNoOpinion;
+  }
+
+  if (temp_thread_state == eStateSuspended ||
+      temp_thread_state == eStateInvalid) {
+    LLDB_LOGF(log,
+              "Thread::ShouldReportStop() tid = 0x%4.4" PRIx64
+              ": returning vote %i (temporary state was suspended or invalid)",
+              GetID(), eVoteNoOpinion);
+    return eVoteNoOpinion;
+  }
+
+  if (!ThreadStoppedForAReason()) {
+    LLDB_LOGF(log,
+              "Thread::ShouldReportStop() tid = 0x%4.4" PRIx64
+              ": returning vote %i (thread didn't stop for a reason.)",
+              GetID(), eVoteNoOpinion);
+    return eVoteNoOpinion;
+  }
+
+  if (m_completed_plan_stack.size() > 0) {
+    // Don't use GetCompletedPlan here, since that suppresses private plans.
+    LLDB_LOGF(log,
+              "Thread::ShouldReportStop() tid = 0x%4.4" PRIx64
+              ": returning vote  for complete stack's back plan",
+              GetID());
+    return m_completed_plan_stack.back()->ShouldReportStop(event_ptr);
+  } else {
+    Vote thread_vote = eVoteNoOpinion;
+    ThreadPlan *plan_ptr = GetCurrentPlan();
+    while (true) {
+      if (plan_ptr->PlanExplainsStop(event_ptr)) {
+        thread_vote = plan_ptr->ShouldReportStop(event_ptr);
+        break;
+      }
+      if (PlanIsBasePlan(plan_ptr))
+        break;
+      else
+        plan_ptr = GetPreviousPlan(plan_ptr);
+    }
+    LLDB_LOGF(log,
+              "Thread::ShouldReportStop() tid = 0x%4.4" PRIx64
+              ": returning vote %i for current plan",
+              GetID(), thread_vote);
+
+    return thread_vote;
+  }
+}
+
+Vote Thread::ShouldReportRun(Event *event_ptr) {
+  StateType thread_state = GetResumeState();
+
+  if (thread_state == eStateSuspended || thread_state == eStateInvalid) {
+    return eVoteNoOpinion;
+  }
+
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+  if (m_completed_plan_stack.size() > 0) {
+    // Don't use GetCompletedPlan here, since that suppresses private plans.
+    LLDB_LOGF(log,
+              "Current Plan for thread %d(%p) (0x%4.4" PRIx64
+              ", %s): %s being asked whether we should report run.",
+              GetIndexID(), static_cast<void *>(this), GetID(),
+              StateAsCString(GetTemporaryResumeState()),
+              m_completed_plan_stack.back()->GetName());
+
+    return m_completed_plan_stack.back()->ShouldReportRun(event_ptr);
+  } else {
+    LLDB_LOGF(log,
+              "Current Plan for thread %d(%p) (0x%4.4" PRIx64
+              ", %s): %s being asked whether we should report run.",
+              GetIndexID(), static_cast<void *>(this), GetID(),
+              StateAsCString(GetTemporaryResumeState()),
+              GetCurrentPlan()->GetName());
+
+    return GetCurrentPlan()->ShouldReportRun(event_ptr);
+  }
+}
+
+bool Thread::MatchesSpec(const ThreadSpec *spec) {
+  return (spec == nullptr) ? true : spec->ThreadPassesBasicTests(*this);
+}
+
+void Thread::PushPlan(ThreadPlanSP &thread_plan_sp) {
+  if (thread_plan_sp) {
+    // If the thread plan doesn't already have a tracer, give it its parent's
+    // tracer:
+    if (!thread_plan_sp->GetThreadPlanTracer()) {
+      assert(!m_plan_stack.empty());
+      thread_plan_sp->SetThreadPlanTracer(
+          m_plan_stack.back()->GetThreadPlanTracer());
+    }
+    m_plan_stack.push_back(thread_plan_sp);
+
+    thread_plan_sp->DidPush();
+
+    Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+    if (log) {
+      StreamString s;
+      thread_plan_sp->GetDescription(&s, lldb::eDescriptionLevelFull);
+      LLDB_LOGF(log, "Thread::PushPlan(0x%p): \"%s\", tid = 0x%4.4" PRIx64 ".",
+                static_cast<void *>(this), s.GetData(),
+                thread_plan_sp->GetThread().GetID());
+    }
+  }
+}
+
+void Thread::PopPlan() {
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+
+  if (m_plan_stack.size() <= 1)
+    return;
+  else {
+    ThreadPlanSP &plan = m_plan_stack.back();
+    if (log) {
+      LLDB_LOGF(log, "Popping plan: \"%s\", tid = 0x%4.4" PRIx64 ".",
+                plan->GetName(), plan->GetThread().GetID());
+    }
+    m_completed_plan_stack.push_back(plan);
+    plan->WillPop();
+    m_plan_stack.pop_back();
+  }
+}
+
+void Thread::DiscardPlan() {
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+  if (m_plan_stack.size() > 1) {
+    ThreadPlanSP &plan = m_plan_stack.back();
+    LLDB_LOGF(log, "Discarding plan: \"%s\", tid = 0x%4.4" PRIx64 ".",
+              plan->GetName(), plan->GetThread().GetID());
+
+    m_discarded_plan_stack.push_back(plan);
+    plan->WillPop();
+    m_plan_stack.pop_back();
+  }
+}
+
+ThreadPlan *Thread::GetCurrentPlan() {
+  // There will always be at least the base plan.  If somebody is mucking with
+  // a thread with an empty plan stack, we should assert right away.
+  return m_plan_stack.empty() ? nullptr : m_plan_stack.back().get();
+}
+
+ThreadPlanSP Thread::GetCompletedPlan() {
+  ThreadPlanSP empty_plan_sp;
+  if (!m_completed_plan_stack.empty()) {
+    for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--) {
+      ThreadPlanSP completed_plan_sp;
+      completed_plan_sp = m_completed_plan_stack[i];
+      if (!completed_plan_sp->GetPrivate())
+        return completed_plan_sp;
+    }
+  }
+  return empty_plan_sp;
+}
+
+ValueObjectSP Thread::GetReturnValueObject() {
+  if (!m_completed_plan_stack.empty()) {
+    for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--) {
+      ValueObjectSP return_valobj_sp;
+      return_valobj_sp = m_completed_plan_stack[i]->GetReturnValueObject();
+      if (return_valobj_sp)
+        return return_valobj_sp;
+    }
+  }
+  return ValueObjectSP();
+}
+
+ExpressionVariableSP Thread::GetExpressionVariable() {
+  if (!m_completed_plan_stack.empty()) {
+    for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--) {
+      ExpressionVariableSP expression_variable_sp;
+      expression_variable_sp =
+          m_completed_plan_stack[i]->GetExpressionVariable();
+      if (expression_variable_sp)
+        return expression_variable_sp;
+    }
+  }
+  return ExpressionVariableSP();
+}
+
+bool Thread::IsThreadPlanDone(ThreadPlan *plan) {
+  if (!m_completed_plan_stack.empty()) {
+    for (int i = m_completed_plan_stack.size() - 1; i >= 0; i--) {
+      if (m_completed_plan_stack[i].get() == plan)
+        return true;
+    }
+  }
+  return false;
+}
+
+bool Thread::WasThreadPlanDiscarded(ThreadPlan *plan) {
+  if (!m_discarded_plan_stack.empty()) {
+    for (int i = m_discarded_plan_stack.size() - 1; i >= 0; i--) {
+      if (m_discarded_plan_stack[i].get() == plan)
+        return true;
+    }
+  }
+  return false;
+}
+
+bool Thread::CompletedPlanOverridesBreakpoint() {
+  return (!m_completed_plan_stack.empty()) ;
+}
+
+ThreadPlan *Thread::GetPreviousPlan(ThreadPlan *current_plan) {
+  if (current_plan == nullptr)
+    return nullptr;
+
+  int stack_size = m_completed_plan_stack.size();
+  for (int i = stack_size - 1; i > 0; i--) {
+    if (current_plan == m_completed_plan_stack[i].get())
+      return m_completed_plan_stack[i - 1].get();
+  }
+
+  if (stack_size > 0 && m_completed_plan_stack[0].get() == current_plan) {
+    return GetCurrentPlan();
+  }
+
+  stack_size = m_plan_stack.size();
+  for (int i = stack_size - 1; i > 0; i--) {
+    if (current_plan == m_plan_stack[i].get())
+      return m_plan_stack[i - 1].get();
+  }
+  return nullptr;
+}
+
+Status Thread::QueueThreadPlan(ThreadPlanSP &thread_plan_sp,
+                               bool abort_other_plans) {
+  Status status;
+  StreamString s;
+  if (!thread_plan_sp->ValidatePlan(&s)) {
+    DiscardThreadPlansUpToPlan(thread_plan_sp);
+    thread_plan_sp.reset();
+    status.SetErrorString(s.GetString());
+    return status;
+  }
+
+  if (abort_other_plans)
+    DiscardThreadPlans(true);
+
+  PushPlan(thread_plan_sp);
+
+  // This seems a little funny, but I don't want to have to split up the
+  // constructor and the DidPush in the scripted plan, that seems annoying.
+  // That means the constructor has to be in DidPush. So I have to validate the
+  // plan AFTER pushing it, and then take it off again...
+  if (!thread_plan_sp->ValidatePlan(&s)) {
+    DiscardThreadPlansUpToPlan(thread_plan_sp);
+    thread_plan_sp.reset();
+    status.SetErrorString(s.GetString());
+    return status;
+  }
+
+  return status;
+}
+
+void Thread::EnableTracer(bool value, bool single_stepping) {
+  int stack_size = m_plan_stack.size();
+  for (int i = 0; i < stack_size; i++) {
+    if (m_plan_stack[i]->GetThreadPlanTracer()) {
+      m_plan_stack[i]->GetThreadPlanTracer()->EnableTracing(value);
+      m_plan_stack[i]->GetThreadPlanTracer()->EnableSingleStep(single_stepping);
+    }
+  }
+}
+
+void Thread::SetTracer(lldb::ThreadPlanTracerSP &tracer_sp) {
+  int stack_size = m_plan_stack.size();
+  for (int i = 0; i < stack_size; i++)
+    m_plan_stack[i]->SetThreadPlanTracer(tracer_sp);
+}
+
+bool Thread::DiscardUserThreadPlansUpToIndex(uint32_t thread_index) {
+  // Count the user thread plans from the back end to get the number of the one
+  // we want to discard:
+
+  uint32_t idx = 0;
+  ThreadPlan *up_to_plan_ptr = nullptr;
+
+  for (ThreadPlanSP plan_sp : m_plan_stack) {
+    if (plan_sp->GetPrivate())
+      continue;
+    if (idx == thread_index) {
+      up_to_plan_ptr = plan_sp.get();
+      break;
+    } else
+      idx++;
+  }
+
+  if (up_to_plan_ptr == nullptr)
+    return false;
+
+  DiscardThreadPlansUpToPlan(up_to_plan_ptr);
+  return true;
+}
+
+void Thread::DiscardThreadPlansUpToPlan(lldb::ThreadPlanSP &up_to_plan_sp) {
+  DiscardThreadPlansUpToPlan(up_to_plan_sp.get());
+}
+
+void Thread::DiscardThreadPlansUpToPlan(ThreadPlan *up_to_plan_ptr) {
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+  LLDB_LOGF(log,
+            "Discarding thread plans for thread tid = 0x%4.4" PRIx64
+            ", up to %p",
+            GetID(), static_cast<void *>(up_to_plan_ptr));
+
+  int stack_size = m_plan_stack.size();
+
+  // If the input plan is nullptr, discard all plans.  Otherwise make sure this
+  // plan is in the stack, and if so discard up to and including it.
+
+  if (up_to_plan_ptr == nullptr) {
+    for (int i = stack_size - 1; i > 0; i--)
+      DiscardPlan();
+  } else {
+    bool found_it = false;
+    for (int i = stack_size - 1; i > 0; i--) {
+      if (m_plan_stack[i].get() == up_to_plan_ptr)
+        found_it = true;
+    }
+    if (found_it) {
+      bool last_one = false;
+      for (int i = stack_size - 1; i > 0 && !last_one; i--) {
+        if (GetCurrentPlan() == up_to_plan_ptr)
+          last_one = true;
+        DiscardPlan();
+      }
+    }
+  }
+}
+
+void Thread::DiscardThreadPlans(bool force) {
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
+  if (log) {
+    LLDB_LOGF(log,
+              "Discarding thread plans for thread (tid = 0x%4.4" PRIx64
+              ", force %d)",
+              GetID(), force);
+  }
+
+  if (force) {
+    int stack_size = m_plan_stack.size();
+    for (int i = stack_size - 1; i > 0; i--) {
+      DiscardPlan();
+    }
+    return;
+  }
+
+  while (true) {
+    int master_plan_idx;
+    bool discard = true;
+
+    // Find the first master plan, see if it wants discarding, and if yes
+    // discard up to it.
+    for (master_plan_idx = m_plan_stack.size() - 1; master_plan_idx >= 0;
+         master_plan_idx--) {
+      if (m_plan_stack[master_plan_idx]->IsMasterPlan()) {
+        discard = m_plan_stack[master_plan_idx]->OkayToDiscard();
+        break;
+      }
+    }
+
+    if (discard) {
+      // First pop all the dependent plans:
+      for (int i = m_plan_stack.size() - 1; i > master_plan_idx; i--) {
+        // FIXME: Do we need a finalize here, or is the rule that
+        // "PrepareForStop"
+        // for the plan leaves it in a state that it is safe to pop the plan
+        // with no more notice?
+        DiscardPlan();
+      }
+
+      // Now discard the master plan itself.
+      // The bottom-most plan never gets discarded.  "OkayToDiscard" for it
+      // means discard it's dependent plans, but not it...
+      if (master_plan_idx > 0) {
+        DiscardPlan();
+      }
+    } else {
+      // If the master plan doesn't want to get discarded, then we're done.
+      break;
+    }
+  }
+}
+
+bool Thread::PlanIsBasePlan(ThreadPlan *plan_ptr) {
+  if (plan_ptr->IsBasePlan())
+    return true;
+  else if (m_plan_stack.size() == 0)
+    return false;
+  else
+    return m_plan_stack[0].get() == plan_ptr;
+}
+
+Status Thread::UnwindInnermostExpression() {
+  Status error;
+  int stack_size = m_plan_stack.size();
+
+  // If the input plan is nullptr, discard all plans.  Otherwise make sure this
+  // plan is in the stack, and if so discard up to and including it.
+
+  for (int i = stack_size - 1; i > 0; i--) {
+    if (m_plan_stack[i]->GetKind() == ThreadPlan::eKindCallFunction) {
+      DiscardThreadPlansUpToPlan(m_plan_stack[i].get());
+      return error;
+    }
+  }
+  error.SetErrorString("No expressions currently active on this thread");
+  return error;
+}
+
+ThreadPlanSP Thread::QueueFundamentalPlan(bool abort_other_plans) {
+  ThreadPlanSP thread_plan_sp(new ThreadPlanBase(*this));
+  QueueThreadPlan(thread_plan_sp, abort_other_plans);
+  return thread_plan_sp;
+}
+
+ThreadPlanSP Thread::QueueThreadPlanForStepSingleInstruction(
+    bool step_over, bool abort_other_plans, bool stop_other_threads,
+    Status &status) {
+  ThreadPlanSP thread_plan_sp(new ThreadPlanStepInstruction(
+      *this, step_over, stop_other_threads, eVoteNoOpinion, eVoteNoOpinion));
+  status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
+  return thread_plan_sp;
+}
+
+ThreadPlanSP Thread::QueueThreadPlanForStepOverRange(
+    bool abort_other_plans, const AddressRange &range,
+    const SymbolContext &addr_context, lldb::RunMode stop_other_threads,
+    Status &status, LazyBool step_out_avoids_code_withoug_debug_info) {
+  ThreadPlanSP thread_plan_sp;
+  thread_plan_sp = std::make_shared<ThreadPlanStepOverRange>(
+      *this, range, addr_context, stop_other_threads,
+      step_out_avoids_code_withoug_debug_info);
+
+  status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
+  return thread_plan_sp;
+}
+
+// Call the QueueThreadPlanForStepOverRange method which takes an address
+// range.
+ThreadPlanSP Thread::QueueThreadPlanForStepOverRange(
+    bool abort_other_plans, const LineEntry &line_entry,
+    const SymbolContext &addr_context, lldb::RunMode stop_other_threads,
+    Status &status, LazyBool step_out_avoids_code_withoug_debug_info) {
+  const bool include_inlined_functions = true;
+  auto address_range =
+      line_entry.GetSameLineContiguousAddressRange(include_inlined_functions);
+  return QueueThreadPlanForStepOverRange(
+      abort_other_plans, address_range, addr_context, stop_other_threads,
+      status, step_out_avoids_code_withoug_debug_info);
+}
+
+ThreadPlanSP Thread::QueueThreadPlanForStepInRange(
+    bool abort_other_plans, const AddressRange &range,
+    const SymbolContext &addr_context, const char *step_in_target,
+    lldb::RunMode stop_other_threads, Status &status,
+    LazyBool step_in_avoids_code_without_debug_info,
+    LazyBool step_out_avoids_code_without_debug_info) {
+  ThreadPlanSP thread_plan_sp(
+      new ThreadPlanStepInRange(*this, range, addr_context, stop_other_threads,
+                                step_in_avoids_code_without_debug_info,
+                                step_out_avoids_code_without_debug_info));
+  ThreadPlanStepInRange *plan =
+      static_cast<ThreadPlanStepInRange *>(thread_plan_sp.get());
+
+  if (step_in_target)
+    plan->SetStepInTarget(step_in_target);
+
+  status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
+  return thread_plan_sp;
+}
+
+// Call the QueueThreadPlanForStepInRange method which takes an address range.
+ThreadPlanSP Thread::QueueThreadPlanForStepInRange(
+    bool abort_other_plans, const LineEntry &line_entry,
+    const SymbolContext &addr_context, const char *step_in_target,
+    lldb::RunMode stop_other_threads, Status &status,
+    LazyBool step_in_avoids_code_without_debug_info,
+    LazyBool step_out_avoids_code_without_debug_info) {
+  const bool include_inlined_functions = false;
+  return QueueThreadPlanForStepInRange(
+      abort_other_plans,
+      line_entry.GetSameLineContiguousAddressRange(include_inlined_functions),
+      addr_context, step_in_target, stop_other_threads, status,
+      step_in_avoids_code_without_debug_info,
+      step_out_avoids_code_without_debug_info);
+}
+
+ThreadPlanSP Thread::QueueThreadPlanForStepOut(
+    bool abort_other_plans, SymbolContext *addr_context, bool first_insn,
+    bool stop_other_threads, Vote stop_vote, Vote run_vote, uint32_t frame_idx,
+    Status &status, LazyBool step_out_avoids_code_without_debug_info) {
+  ThreadPlanSP thread_plan_sp(new ThreadPlanStepOut(
+      *this, addr_context, first_insn, stop_other_threads, stop_vote, run_vote,
+      frame_idx, step_out_avoids_code_without_debug_info));
+
+  status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
+  return thread_plan_sp;
+}
+
+ThreadPlanSP Thread::QueueThreadPlanForStepOutNoShouldStop(
+    bool abort_other_plans, SymbolContext *addr_context, bool first_insn,
+    bool stop_other_threads, Vote stop_vote, Vote run_vote, uint32_t frame_idx,
+    Status &status, bool continue_to_next_branch) {
+  const bool calculate_return_value =
+      false; // No need to calculate the return value here.
+  ThreadPlanSP thread_plan_sp(new ThreadPlanStepOut(
+      *this, addr_context, first_insn, stop_other_threads, stop_vote, run_vote,
+      frame_idx, eLazyBoolNo, continue_to_next_branch, calculate_return_value));
+
+  ThreadPlanStepOut *new_plan =
+      static_cast<ThreadPlanStepOut *>(thread_plan_sp.get());
+  new_plan->ClearShouldStopHereCallbacks();
+
+  status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
+  return thread_plan_sp;
+}
+
+ThreadPlanSP Thread::QueueThreadPlanForStepThrough(StackID &return_stack_id,
+                                                   bool abort_other_plans,
+                                                   bool stop_other_threads,
+                                                   Status &status) {
+  ThreadPlanSP thread_plan_sp(
+      new ThreadPlanStepThrough(*this, return_stack_id, stop_other_threads));
+  if (!thread_plan_sp || !thread_plan_sp->ValidatePlan(nullptr))
+    return ThreadPlanSP();
+
+  status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
+  return thread_plan_sp;
+}
+
+ThreadPlanSP Thread::QueueThreadPlanForRunToAddress(bool abort_other_plans,
+                                                    Address &target_addr,
+                                                    bool stop_other_threads,
+                                                    Status &status) {
+  ThreadPlanSP thread_plan_sp(
+      new ThreadPlanRunToAddress(*this, target_addr, stop_other_threads));
+
+  status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
+  return thread_plan_sp;
+}
+
+ThreadPlanSP Thread::QueueThreadPlanForStepUntil(
+    bool abort_other_plans, lldb::addr_t *address_list, size_t num_addresses,
+    bool stop_other_threads, uint32_t frame_idx, Status &status) {
+  ThreadPlanSP thread_plan_sp(new ThreadPlanStepUntil(
+      *this, address_list, num_addresses, stop_other_threads, frame_idx));
+
+  status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
+  return thread_plan_sp;
+}
+
+lldb::ThreadPlanSP Thread::QueueThreadPlanForStepScripted(
+    bool abort_other_plans, const char *class_name, 
+    StructuredData::ObjectSP extra_args_sp,  bool stop_other_threads,
+    Status &status) {
+    
+  StructuredDataImpl *extra_args_impl = nullptr; 
+  if (extra_args_sp) {
+    extra_args_impl = new StructuredDataImpl();
+    extra_args_impl->SetObjectSP(extra_args_sp);
+  }
+
+  ThreadPlanSP thread_plan_sp(new ThreadPlanPython(*this, class_name, 
+                                                   extra_args_impl));
+
+  status = QueueThreadPlan(thread_plan_sp, abort_other_plans);
+  return thread_plan_sp;
+}
+
+uint32_t Thread::GetIndexID() const { return m_index_id; }
+
+static void PrintPlanElement(Stream *s, const ThreadPlanSP &plan,
+                             lldb::DescriptionLevel desc_level,
+                             int32_t elem_idx) {
+  s->IndentMore();
+  s->Indent();
+  s->Printf("Element %d: ", elem_idx);
+  plan->GetDescription(s, desc_level);
+  s->EOL();
+  s->IndentLess();
+}
+
+static void PrintPlanStack(Stream *s,
+                           const std::vector<lldb::ThreadPlanSP> &plan_stack,
+                           lldb::DescriptionLevel desc_level,
+                           bool include_internal) {
+  int32_t print_idx = 0;
+  for (ThreadPlanSP plan_sp : plan_stack) {
+    if (include_internal || !plan_sp->GetPrivate()) {
+      PrintPlanElement(s, plan_sp, desc_level, print_idx++);
+    }
+  }
+}
+
+void Thread::DumpThreadPlans(Stream *s, lldb::DescriptionLevel desc_level,
+                             bool include_internal,
+                             bool ignore_boring_threads) const {
+  uint32_t stack_size;
+
+  if (ignore_boring_threads) {
+    uint32_t stack_size = m_plan_stack.size();
+    uint32_t completed_stack_size = m_completed_plan_stack.size();
+    uint32_t discarded_stack_size = m_discarded_plan_stack.size();
+    if (stack_size == 1 && completed_stack_size == 0 &&
+        discarded_stack_size == 0) {
+      s->Printf("thread #%u: tid = 0x%4.4" PRIx64 "\n", GetIndexID(), GetID());
+      s->IndentMore();
+      s->Indent();
+      s->Printf("No active thread plans\n");
+      s->IndentLess();
+      return;
+    }
+  }
+
+  s->Indent();
+  s->Printf("thread #%u: tid = 0x%4.4" PRIx64 ":\n", GetIndexID(), GetID());
+  s->IndentMore();
+  s->Indent();
+  s->Printf("Active plan stack:\n");
+  PrintPlanStack(s, m_plan_stack, desc_level, include_internal);
+
+  stack_size = m_completed_plan_stack.size();
+  if (stack_size > 0) {
+    s->Indent();
+    s->Printf("Completed Plan Stack:\n");
+    PrintPlanStack(s, m_completed_plan_stack, desc_level, include_internal);
+  }
+
+  stack_size = m_discarded_plan_stack.size();
+  if (stack_size > 0) {
+    s->Indent();
+    s->Printf("Discarded Plan Stack:\n");
+    PrintPlanStack(s, m_discarded_plan_stack, desc_level, include_internal);
+  }
+
+  s->IndentLess();
+}
+
+TargetSP Thread::CalculateTarget() {
+  TargetSP target_sp;
+  ProcessSP process_sp(GetProcess());
+  if (process_sp)
+    target_sp = process_sp->CalculateTarget();
+  return target_sp;
+}
+
+ProcessSP Thread::CalculateProcess() { return GetProcess(); }
+
+ThreadSP Thread::CalculateThread() { return shared_from_this(); }
+
+StackFrameSP Thread::CalculateStackFrame() { return StackFrameSP(); }
+
+void Thread::CalculateExecutionContext(ExecutionContext &exe_ctx) {
+  exe_ctx.SetContext(shared_from_this());
+}
+
+StackFrameListSP Thread::GetStackFrameList() {
+  std::lock_guard<std::recursive_mutex> guard(m_frame_mutex);
+
+  if (!m_curr_frames_sp)
+    m_curr_frames_sp =
+        std::make_shared<StackFrameList>(*this, m_prev_frames_sp, true);
+
+  return m_curr_frames_sp;
+}
+
+void Thread::ClearStackFrames() {
+  std::lock_guard<std::recursive_mutex> guard(m_frame_mutex);
+
+  Unwind *unwinder = GetUnwinder();
+  if (unwinder)
+    unwinder->Clear();
+
+  // Only store away the old "reference" StackFrameList if we got all its
+  // frames:
+  // FIXME: At some point we can try to splice in the frames we have fetched
+  // into
+  // the new frame as we make it, but let's not try that now.
+  if (m_curr_frames_sp && m_curr_frames_sp->GetAllFramesFetched())
+    m_prev_frames_sp.swap(m_curr_frames_sp);
+  m_curr_frames_sp.reset();
+
+  m_extended_info.reset();
+  m_extended_info_fetched = false;
+}
+
+lldb::StackFrameSP Thread::GetFrameWithConcreteFrameIndex(uint32_t unwind_idx) {
+  return GetStackFrameList()->GetFrameWithConcreteFrameIndex(unwind_idx);
+}
+
+Status Thread::ReturnFromFrameWithIndex(uint32_t frame_idx,
+                                        lldb::ValueObjectSP return_value_sp,
+                                        bool broadcast) {
+  StackFrameSP frame_sp = GetStackFrameAtIndex(frame_idx);
+  Status return_error;
+
+  if (!frame_sp) {
+    return_error.SetErrorStringWithFormat(
+        "Could not find frame with index %d in thread 0x%" PRIx64 ".",
+        frame_idx, GetID());
+  }
+
+  return ReturnFromFrame(frame_sp, return_value_sp, broadcast);
+}
+
+Status Thread::ReturnFromFrame(lldb::StackFrameSP frame_sp,
+                               lldb::ValueObjectSP return_value_sp,
+                               bool broadcast) {
+  Status return_error;
+
+  if (!frame_sp) {
+    return_error.SetErrorString("Can't return to a null frame.");
+    return return_error;
+  }
+
+  Thread *thread = frame_sp->GetThread().get();
+  uint32_t older_frame_idx = frame_sp->GetFrameIndex() + 1;
+  StackFrameSP older_frame_sp = thread->GetStackFrameAtIndex(older_frame_idx);
+  if (!older_frame_sp) {
+    return_error.SetErrorString("No older frame to return to.");
+    return return_error;
+  }
+
+  if (return_value_sp) {
+    lldb::ABISP abi = thread->GetProcess()->GetABI();
+    if (!abi) {
+      return_error.SetErrorString("Could not find ABI to set return value.");
+      return return_error;
+    }
+    SymbolContext sc = frame_sp->GetSymbolContext(eSymbolContextFunction);
+
+    // FIXME: ValueObject::Cast doesn't currently work correctly, at least not
+    // for scalars.
+    // Turn that back on when that works.
+    if (/* DISABLES CODE */ (false) && sc.function != nullptr) {
+      Type *function_type = sc.function->GetType();
+      if (function_type) {
+        CompilerType return_type =
+            sc.function->GetCompilerType().GetFunctionReturnType();
+        if (return_type) {
+          StreamString s;
+          return_type.DumpTypeDescription(&s);
+          ValueObjectSP cast_value_sp = return_value_sp->Cast(return_type);
+          if (cast_value_sp) {
+            cast_value_sp->SetFormat(eFormatHex);
+            return_value_sp = cast_value_sp;
+          }
+        }
+      }
+    }
+
+    return_error = abi->SetReturnValueObject(older_frame_sp, return_value_sp);
+    if (!return_error.Success())
+      return return_error;
+  }
+
+  // Now write the return registers for the chosen frame: Note, we can't use
+  // ReadAllRegisterValues->WriteAllRegisterValues, since the read & write cook
+  // their data
+
+  StackFrameSP youngest_frame_sp = thread->GetStackFrameAtIndex(0);
+  if (youngest_frame_sp) {
+    lldb::RegisterContextSP reg_ctx_sp(youngest_frame_sp->GetRegisterContext());
+    if (reg_ctx_sp) {
+      bool copy_success = reg_ctx_sp->CopyFromRegisterContext(
+          older_frame_sp->GetRegisterContext());
+      if (copy_success) {
+        thread->DiscardThreadPlans(true);
+        thread->ClearStackFrames();
+        if (broadcast && EventTypeHasListeners(eBroadcastBitStackChanged))
+          BroadcastEvent(eBroadcastBitStackChanged,
+                         new ThreadEventData(this->shared_from_this()));
+      } else {
+        return_error.SetErrorString("Could not reset register values.");
+      }
+    } else {
+      return_error.SetErrorString("Frame has no register context.");
+    }
+  } else {
+    return_error.SetErrorString("Returned past top frame.");
+  }
+  return return_error;
+}
+
+static void DumpAddressList(Stream &s, const std::vector<Address> &list,
+                            ExecutionContextScope *exe_scope) {
+  for (size_t n = 0; n < list.size(); n++) {
+    s << "\t";
+    list[n].Dump(&s, exe_scope, Address::DumpStyleResolvedDescription,
+                 Address::DumpStyleSectionNameOffset);
+    s << "\n";
+  }
+}
+
+Status Thread::JumpToLine(const FileSpec &file, uint32_t line,
+                          bool can_leave_function, std::string *warnings) {
+  ExecutionContext exe_ctx(GetStackFrameAtIndex(0));
+  Target *target = exe_ctx.GetTargetPtr();
+  TargetSP target_sp = exe_ctx.GetTargetSP();
+  RegisterContext *reg_ctx = exe_ctx.GetRegisterContext();
+  StackFrame *frame = exe_ctx.GetFramePtr();
+  const SymbolContext &sc = frame->GetSymbolContext(eSymbolContextFunction);
+
+  // Find candidate locations.
+  std::vector<Address> candidates, within_function, outside_function;
+  target->GetImages().FindAddressesForLine(target_sp, file, line, sc.function,
+                                           within_function, outside_function);
+
+  // If possible, we try and stay within the current function. Within a
+  // function, we accept multiple locations (optimized code may do this,
+  // there's no solution here so we do the best we can). However if we're
+  // trying to leave the function, we don't know how to pick the right
+  // location, so if there's more than one then we bail.
+  if (!within_function.empty())
+    candidates = within_function;
+  else if (outside_function.size() == 1 && can_leave_function)
+    candidates = outside_function;
+
+  // Check if we got anything.
+  if (candidates.empty()) {
+    if (outside_function.empty()) {
+      return Status("Cannot locate an address for %s:%i.",
+                    file.GetFilename().AsCString(), line);
+    } else if (outside_function.size() == 1) {
+      return Status("%s:%i is outside the current function.",
+                    file.GetFilename().AsCString(), line);
+    } else {
+      StreamString sstr;
+      DumpAddressList(sstr, outside_function, target);
+      return Status("%s:%i has multiple candidate locations:\n%s",
+                    file.GetFilename().AsCString(), line, sstr.GetData());
+    }
+  }
+
+  // Accept the first location, warn about any others.
+  Address dest = candidates[0];
+  if (warnings && candidates.size() > 1) {
+    StreamString sstr;
+    sstr.Printf("%s:%i appears multiple times in this function, selecting the "
+                "first location:\n",
+                file.GetFilename().AsCString(), line);
+    DumpAddressList(sstr, candidates, target);
+    *warnings = sstr.GetString();
+  }
+
+  if (!reg_ctx->SetPC(dest))
+    return Status("Cannot change PC to target address.");
+
+  return Status();
+}
+
+void Thread::DumpUsingSettingsFormat(Stream &strm, uint32_t frame_idx,
+                                     bool stop_format) {
+  ExecutionContext exe_ctx(shared_from_this());
+  Process *process = exe_ctx.GetProcessPtr();
+  if (process == nullptr)
+    return;
+
+  StackFrameSP frame_sp;
+  SymbolContext frame_sc;
+  if (frame_idx != LLDB_INVALID_FRAME_ID) {
+    frame_sp = GetStackFrameAtIndex(frame_idx);
+    if (frame_sp) {
+      exe_ctx.SetFrameSP(frame_sp);
+      frame_sc = frame_sp->GetSymbolContext(eSymbolContextEverything);
+    }
+  }
+
+  const FormatEntity::Entry *thread_format;
+  if (stop_format)
+    thread_format = exe_ctx.GetTargetRef().GetDebugger().GetThreadStopFormat();
+  else
+    thread_format = exe_ctx.GetTargetRef().GetDebugger().GetThreadFormat();
+
+  assert(thread_format);
+
+  FormatEntity::Format(*thread_format, strm, frame_sp ? &frame_sc : nullptr,
+                       &exe_ctx, nullptr, nullptr, false, false);
+}
+
+void Thread::SettingsInitialize() {}
+
+void Thread::SettingsTerminate() {}
+
+lldb::addr_t Thread::GetThreadPointer() { return LLDB_INVALID_ADDRESS; }
+
+addr_t Thread::GetThreadLocalData(const ModuleSP module,
+                                  lldb::addr_t tls_file_addr) {
+  // The default implementation is to ask the dynamic loader for it. This can
+  // be overridden for specific platforms.
+  DynamicLoader *loader = GetProcess()->GetDynamicLoader();
+  if (loader)
+    return loader->GetThreadLocalData(module, shared_from_this(),
+                                      tls_file_addr);
+  else
+    return LLDB_INVALID_ADDRESS;
+}
+
+bool Thread::SafeToCallFunctions() {
+  Process *process = GetProcess().get();
+  if (process) {
+    SystemRuntime *runtime = process->GetSystemRuntime();
+    if (runtime) {
+      return runtime->SafeToCallFunctionsOnThisThread(shared_from_this());
+    }
+  }
+  return true;
+}
+
+lldb::StackFrameSP
+Thread::GetStackFrameSPForStackFramePtr(StackFrame *stack_frame_ptr) {
+  return GetStackFrameList()->GetStackFrameSPForStackFramePtr(stack_frame_ptr);
+}
+
+const char *Thread::StopReasonAsCString(lldb::StopReason reason) {
+  switch (reason) {
+  case eStopReasonInvalid:
+    return "invalid";
+  case eStopReasonNone:
+    return "none";
+  case eStopReasonTrace:
+    return "trace";
+  case eStopReasonBreakpoint:
+    return "breakpoint";
+  case eStopReasonWatchpoint:
+    return "watchpoint";
+  case eStopReasonSignal:
+    return "signal";
+  case eStopReasonException:
+    return "exception";
+  case eStopReasonExec:
+    return "exec";
+  case eStopReasonPlanComplete:
+    return "plan complete";
+  case eStopReasonThreadExiting:
+    return "thread exiting";
+  case eStopReasonInstrumentation:
+    return "instrumentation break";
+  }
+
+  static char unknown_state_string[64];
+  snprintf(unknown_state_string, sizeof(unknown_state_string),
+           "StopReason = %i", reason);
+  return unknown_state_string;
+}
+
+const char *Thread::RunModeAsCString(lldb::RunMode mode) {
+  switch (mode) {
+  case eOnlyThisThread:
+    return "only this thread";
+  case eAllThreads:
+    return "all threads";
+  case eOnlyDuringStepping:
+    return "only during stepping";
+  }
+
+  static char unknown_state_string[64];
+  snprintf(unknown_state_string, sizeof(unknown_state_string), "RunMode = %i",
+           mode);
+  return unknown_state_string;
+}
+
+size_t Thread::GetStatus(Stream &strm, uint32_t start_frame,
+                         uint32_t num_frames, uint32_t num_frames_with_source,
+                         bool stop_format, bool only_stacks) {
+
+  if (!only_stacks) {
+    ExecutionContext exe_ctx(shared_from_this());
+    Target *target = exe_ctx.GetTargetPtr();
+    Process *process = exe_ctx.GetProcessPtr();
+    strm.Indent();
+    bool is_selected = false;
+    if (process) {
+      if (process->GetThreadList().GetSelectedThread().get() == this)
+        is_selected = true;
+    }
+    strm.Printf("%c ", is_selected ? '*' : ' ');
+    if (target && target->GetDebugger().GetUseExternalEditor()) {
+      StackFrameSP frame_sp = GetStackFrameAtIndex(start_frame);
+      if (frame_sp) {
+        SymbolContext frame_sc(
+            frame_sp->GetSymbolContext(eSymbolContextLineEntry));
+        if (frame_sc.line_entry.line != 0 && frame_sc.line_entry.file) {
+          Host::OpenFileInExternalEditor(frame_sc.line_entry.file,
+                                         frame_sc.line_entry.line);
+        }
+      }
+    }
+
+    DumpUsingSettingsFormat(strm, start_frame, stop_format);
+  }
+
+  size_t num_frames_shown = 0;
+  if (num_frames > 0) {
+    strm.IndentMore();
+
+    const bool show_frame_info = true;
+    const bool show_frame_unique = only_stacks;
+    const char *selected_frame_marker = nullptr;
+    if (num_frames == 1 || only_stacks ||
+        (GetID() != GetProcess()->GetThreadList().GetSelectedThread()->GetID()))
+      strm.IndentMore();
+    else
+      selected_frame_marker = "* ";
+
+    num_frames_shown = GetStackFrameList()->GetStatus(
+        strm, start_frame, num_frames, show_frame_info, num_frames_with_source,
+        show_frame_unique, selected_frame_marker);
+    if (num_frames == 1)
+      strm.IndentLess();
+    strm.IndentLess();
+  }
+  return num_frames_shown;
+}
+
+bool Thread::GetDescription(Stream &strm, lldb::DescriptionLevel level,
+                            bool print_json_thread, bool print_json_stopinfo) {
+  const bool stop_format = false;
+  DumpUsingSettingsFormat(strm, 0, stop_format);
+  strm.Printf("\n");
+
+  StructuredData::ObjectSP thread_info = GetExtendedInfo();
+
+  if (print_json_thread || print_json_stopinfo) {
+    if (thread_info && print_json_thread) {
+      thread_info->Dump(strm);
+      strm.Printf("\n");
+    }
+
+    if (print_json_stopinfo && m_stop_info_sp) {
+      StructuredData::ObjectSP stop_info = m_stop_info_sp->GetExtendedInfo();
+      if (stop_info) {
+        stop_info->Dump(strm);
+        strm.Printf("\n");
+      }
+    }
+
+    return true;
+  }
+
+  if (thread_info) {
+    StructuredData::ObjectSP activity =
+        thread_info->GetObjectForDotSeparatedPath("activity");
+    StructuredData::ObjectSP breadcrumb =
+        thread_info->GetObjectForDotSeparatedPath("breadcrumb");
+    StructuredData::ObjectSP messages =
+        thread_info->GetObjectForDotSeparatedPath("trace_messages");
+
+    bool printed_activity = false;
+    if (activity && activity->GetType() == eStructuredDataTypeDictionary) {
+      StructuredData::Dictionary *activity_dict = activity->GetAsDictionary();
+      StructuredData::ObjectSP id = activity_dict->GetValueForKey("id");
+      StructuredData::ObjectSP name = activity_dict->GetValueForKey("name");
+      if (name && name->GetType() == eStructuredDataTypeString && id &&
+          id->GetType() == eStructuredDataTypeInteger) {
+        strm.Format("  Activity '{0}', {1:x}\n",
+                    name->GetAsString()->GetValue(),
+                    id->GetAsInteger()->GetValue());
+      }
+      printed_activity = true;
+    }
+    bool printed_breadcrumb = false;
+    if (breadcrumb && breadcrumb->GetType() == eStructuredDataTypeDictionary) {
+      if (printed_activity)
+        strm.Printf("\n");
+      StructuredData::Dictionary *breadcrumb_dict =
+          breadcrumb->GetAsDictionary();
+      StructuredData::ObjectSP breadcrumb_text =
+          breadcrumb_dict->GetValueForKey("name");
+      if (breadcrumb_text &&
+          breadcrumb_text->GetType() == eStructuredDataTypeString) {
+        strm.Format("  Current Breadcrumb: {0}\n",
+                    breadcrumb_text->GetAsString()->GetValue());
+      }
+      printed_breadcrumb = true;
+    }
+    if (messages && messages->GetType() == eStructuredDataTypeArray) {
+      if (printed_breadcrumb)
+        strm.Printf("\n");
+      StructuredData::Array *messages_array = messages->GetAsArray();
+      const size_t msg_count = messages_array->GetSize();
+      if (msg_count > 0) {
+        strm.Printf("  %zu trace messages:\n", msg_count);
+        for (size_t i = 0; i < msg_count; i++) {
+          StructuredData::ObjectSP message = messages_array->GetItemAtIndex(i);
+          if (message && message->GetType() == eStructuredDataTypeDictionary) {
+            StructuredData::Dictionary *message_dict =
+                message->GetAsDictionary();
+            StructuredData::ObjectSP message_text =
+                message_dict->GetValueForKey("message");
+            if (message_text &&
+                message_text->GetType() == eStructuredDataTypeString) {
+              strm.Format("    {0}\n", message_text->GetAsString()->GetValue());
+            }
+          }
+        }
+      }
+    }
+  }
+
+  return true;
+}
+
+size_t Thread::GetStackFrameStatus(Stream &strm, uint32_t first_frame,
+                                   uint32_t num_frames, bool show_frame_info,
+                                   uint32_t num_frames_with_source) {
+  return GetStackFrameList()->GetStatus(
+      strm, first_frame, num_frames, show_frame_info, num_frames_with_source);
+}
+
+Unwind *Thread::GetUnwinder() {
+  if (!m_unwinder_up) {
+    const ArchSpec target_arch(CalculateTarget()->GetArchitecture());
+    const llvm::Triple::ArchType machine = target_arch.GetMachine();
+    switch (machine) {
+    case llvm::Triple::x86_64:
+    case llvm::Triple::x86:
+    case llvm::Triple::arm:
+    case llvm::Triple::aarch64:
+    case llvm::Triple::aarch64_32:
+    case llvm::Triple::thumb:
+    case llvm::Triple::mips:
+    case llvm::Triple::mipsel:
+    case llvm::Triple::mips64:
+    case llvm::Triple::mips64el:
+    case llvm::Triple::ppc:
+    case llvm::Triple::ppc64:
+    case llvm::Triple::ppc64le:
+    case llvm::Triple::systemz:
+    case llvm::Triple::hexagon:
+    case llvm::Triple::arc:
+      m_unwinder_up.reset(new UnwindLLDB(*this));
+      break;
+
+    default:
+      if (target_arch.GetTriple().getVendor() == llvm::Triple::Apple)
+        m_unwinder_up.reset(new UnwindMacOSXFrameBackchain(*this));
+      break;
+    }
+  }
+  return m_unwinder_up.get();
+}
+
+void Thread::Flush() {
+  ClearStackFrames();
+  m_reg_context_sp.reset();
+}
+
+bool Thread::IsStillAtLastBreakpointHit() {
+  // If we are currently stopped at a breakpoint, always return that stopinfo
+  // and don't reset it. This allows threads to maintain their breakpoint
+  // stopinfo, such as when thread-stepping in multithreaded programs.
+  if (m_stop_info_sp) {
+    StopReason stop_reason = m_stop_info_sp->GetStopReason();
+    if (stop_reason == lldb::eStopReasonBreakpoint) {
+      uint64_t value = m_stop_info_sp->GetValue();
+      lldb::RegisterContextSP reg_ctx_sp(GetRegisterContext());
+      if (reg_ctx_sp) {
+        lldb::addr_t pc = reg_ctx_sp->GetPC();
+        BreakpointSiteSP bp_site_sp =
+            GetProcess()->GetBreakpointSiteList().FindByAddress(pc);
+        if (bp_site_sp && static_cast<break_id_t>(value) == bp_site_sp->GetID())
+          return true;
+      }
+    }
+  }
+  return false;
+}
+
+Status Thread::StepIn(bool source_step,
+                      LazyBool step_in_avoids_code_without_debug_info,
+                      LazyBool step_out_avoids_code_without_debug_info)
+
+{
+  Status error;
+  Process *process = GetProcess().get();
+  if (StateIsStoppedState(process->GetState(), true)) {
+    StackFrameSP frame_sp = GetStackFrameAtIndex(0);
+    ThreadPlanSP new_plan_sp;
+    const lldb::RunMode run_mode = eOnlyThisThread;
+    const bool abort_other_plans = false;
+
+    if (source_step && frame_sp && frame_sp->HasDebugInformation()) {
+      SymbolContext sc(frame_sp->GetSymbolContext(eSymbolContextEverything));
+      new_plan_sp = QueueThreadPlanForStepInRange(
+          abort_other_plans, sc.line_entry, sc, nullptr, run_mode, error,
+          step_in_avoids_code_without_debug_info,
+          step_out_avoids_code_without_debug_info);
+    } else {
+      new_plan_sp = QueueThreadPlanForStepSingleInstruction(
+          false, abort_other_plans, run_mode, error);
+    }
+
+    new_plan_sp->SetIsMasterPlan(true);
+    new_plan_sp->SetOkayToDiscard(false);
+
+    // Why do we need to set the current thread by ID here???
+    process->GetThreadList().SetSelectedThreadByID(GetID());
+    error = process->Resume();
+  } else {
+    error.SetErrorString("process not stopped");
+  }
+  return error;
+}
+
+Status Thread::StepOver(bool source_step,
+                        LazyBool step_out_avoids_code_without_debug_info) {
+  Status error;
+  Process *process = GetProcess().get();
+  if (StateIsStoppedState(process->GetState(), true)) {
+    StackFrameSP frame_sp = GetStackFrameAtIndex(0);
+    ThreadPlanSP new_plan_sp;
+
+    const lldb::RunMode run_mode = eOnlyThisThread;
+    const bool abort_other_plans = false;
+
+    if (source_step && frame_sp && frame_sp->HasDebugInformation()) {
+      SymbolContext sc(frame_sp->GetSymbolContext(eSymbolContextEverything));
+      new_plan_sp = QueueThreadPlanForStepOverRange(
+          abort_other_plans, sc.line_entry, sc, run_mode, error,
+          step_out_avoids_code_without_debug_info);
+    } else {
+      new_plan_sp = QueueThreadPlanForStepSingleInstruction(
+          true, abort_other_plans, run_mode, error);
+    }
+
+    new_plan_sp->SetIsMasterPlan(true);
+    new_plan_sp->SetOkayToDiscard(false);
+
+    // Why do we need to set the current thread by ID here???
+    process->GetThreadList().SetSelectedThreadByID(GetID());
+    error = process->Resume();
+  } else {
+    error.SetErrorString("process not stopped");
+  }
+  return error;
+}
+
+Status Thread::StepOut() {
+  Status error;
+  Process *process = GetProcess().get();
+  if (StateIsStoppedState(process->GetState(), true)) {
+    const bool first_instruction = false;
+    const bool stop_other_threads = false;
+    const bool abort_other_plans = false;
+
+    ThreadPlanSP new_plan_sp(QueueThreadPlanForStepOut(
+        abort_other_plans, nullptr, first_instruction, stop_other_threads,
+        eVoteYes, eVoteNoOpinion, 0, error));
+
+    new_plan_sp->SetIsMasterPlan(true);
+    new_plan_sp->SetOkayToDiscard(false);
+
+    // Why do we need to set the current thread by ID here???
+    process->GetThreadList().SetSelectedThreadByID(GetID());
+    error = process->Resume();
+  } else {
+    error.SetErrorString("process not stopped");
+  }
+  return error;
+}
+
+ValueObjectSP Thread::GetCurrentException() {
+  if (auto frame_sp = GetStackFrameAtIndex(0))
+    if (auto recognized_frame = frame_sp->GetRecognizedFrame())
+      if (auto e = recognized_frame->GetExceptionObject())
+        return e;
+
+  // NOTE: Even though this behavior is generalized, only ObjC is actually
+  // supported at the moment.
+  for (LanguageRuntime *runtime : GetProcess()->GetLanguageRuntimes()) {
+    if (auto e = runtime->GetExceptionObjectForThread(shared_from_this()))
+      return e;
+  }
+
+  return ValueObjectSP();
+}
+
+ThreadSP Thread::GetCurrentExceptionBacktrace() {
+  ValueObjectSP exception = GetCurrentException();
+  if (!exception)
+    return ThreadSP();
+
+  // NOTE: Even though this behavior is generalized, only ObjC is actually
+  // supported at the moment.
+  for (LanguageRuntime *runtime : GetProcess()->GetLanguageRuntimes()) {
+    if (auto bt = runtime->GetBacktraceThreadFromException(exception))
+      return bt;
+  }
+
+  return ThreadSP();
+}