Merge pull request llvm#10000 from felipepiovezan/felipe/remove_migration_customizations

[lldb][NFC] Remove vestigial downstream changes related to ThreadPlan migration

Author: felipepiovezan

lldb/include/lldb/Target/Process.h

@@ -2380,18 +2380,6 @@ bool PruneThreadPlansForTID(lldb::tid_t tid);
 /// Prune ThreadPlanStacks for all unreported threads.
 void PruneThreadPlans();
 
-  void SynchronizeThreadPlans();
-
-  /// From the detached thread plan stacks, find the first stack that explains
-  /// the stop represented by the thread and the event.
-  lldb::ThreadPlanSP FindDetachedPlanExplainingStop(Thread &thread, Event *event_ptr);
-
-  /// Helper function for FindDetachedPlanExplainingStop. Exists only to be
-  /// marked as a C++ friend of `ThreadPlan`.
-  lldb::ThreadPlanSP DoesStackExplainStopNoLock(ThreadPlanStack &stack,
-                                                Thread &thread,
-                                                Event *event_ptr);
-
   /// Find the thread plan stack associated with thread with \a tid.
   ///
   /// \param[in] tid

lldb/include/lldb/Target/ThreadPlan.h

@@ -486,26 +486,6 @@ class ThreadPlan : public std::enable_shared_from_this<ThreadPlan>,
     return m_takes_iteration_count;
   }
 
-  bool IsTID(lldb::tid_t tid) { return tid == m_tid; }
-  bool HasTID() { return m_tid != LLDB_INVALID_THREAD_ID; }
-  lldb::tid_t GetTID() { return m_tid; }
-
-  void SetTID(lldb::tid_t tid) {
-    if (m_tid != tid) {
-      m_tid = tid;
-      ClearThreadCache();
-    }
-  }
-
-  void ClearTID() {
-    m_tid = LLDB_INVALID_THREAD_ID;
-    ClearThreadCache();
-  }
-
-  friend lldb::ThreadPlanSP
-  Process::DoesStackExplainStopNoLock(ThreadPlanStack &stack, Thread &thread,
-                                      Event *event_ptr);
-
 protected:
   // Constructors and Destructors
   ThreadPlan(ThreadPlanKind kind, const char *name, Thread &thread,

lldb/include/lldb/Target/ThreadPlanStack.h

@@ -97,12 +97,6 @@ class ThreadPlanStack {
   /// generated.
   void ClearThreadCache();
 
-  bool IsTID(lldb::tid_t tid) {
-    return GetTID() == tid;
-  }
-  lldb::tid_t GetTID();
-  void SetTID(lldb::tid_t tid);
-
 private:
   lldb::ThreadPlanSP DiscardPlanNoLock();
   lldb::ThreadPlanSP GetCurrentPlanNoLock() const;
@@ -122,9 +116,6 @@ class ThreadPlanStack {
                                           // completed plan checkpoints.
   std::unordered_map<size_t, PlanStack> m_completed_plan_store;
   mutable llvm::sys::RWMutex m_stack_mutex;
-
-  // ThreadPlanStacks shouldn't be copied.
-  ThreadPlanStack(ThreadPlanStack &rhs) = delete;
 };
 
 class ThreadPlanStackMap {
@@ -139,35 +130,16 @@ class ThreadPlanStackMap {
   void AddThread(Thread &thread) {
     std::lock_guard<std::recursive_mutex> guard(m_stack_map_mutex);
     lldb::tid_t tid = thread.GetID();
-    // If we already have a ThreadPlanStack for this thread, use it.
-    if (m_plans_list.find(tid) != m_plans_list.end())
-      return;
-
-    m_plans_up_container.emplace_back(
-        std::make_unique<ThreadPlanStack>(thread));
-    m_plans_list.emplace(tid, m_plans_up_container.back().get());
+    m_plans_list.emplace(tid, thread);
   }
 
   bool RemoveTID(lldb::tid_t tid) {
     std::lock_guard<std::recursive_mutex> guard(m_stack_map_mutex);
     auto result = m_plans_list.find(tid);
     if (result == m_plans_list.end())
       return false;
-    ThreadPlanStack *removed_stack = result->second;
+    result->second.ThreadDestroyed(nullptr);
     m_plans_list.erase(result);
-    // Now find it in the stack storage:
-    auto end = m_plans_up_container.end();
-    auto iter = std::find_if(m_plans_up_container.begin(), end,
-        [&] (std::unique_ptr<ThreadPlanStack> &stack) {
-          return stack->IsTID(tid);
-        });
-    if (iter == end)
-      return false;
-
-    // Then tell the stack its thread has been destroyed:
-    removed_stack->ThreadDestroyed(nullptr);
-    // And then remove it from the container so it goes away.
-    m_plans_up_container.erase(iter);
     return true;
   }
 
@@ -177,69 +149,22 @@ class ThreadPlanStackMap {
     if (result == m_plans_list.end())
       return nullptr;
     else
-      return result->second;
+      return &result->second;
   }
 
   /// Clear the Thread* cache that each ThreadPlan contains.
   ///
   /// This is useful in situations like when a new Thread list is being
   /// generated.
   void ClearThreadCache() {
-    std::lock_guard<std::recursive_mutex> guard(m_stack_map_mutex);
     for (auto &plan_list : m_plans_list)
-      plan_list.second->ClearThreadCache();
-  }
-
-  // rename to Reactivate?
-  void Activate(ThreadPlanStack &stack) {
-    std::lock_guard<std::recursive_mutex> guard(m_stack_map_mutex);
-    // Remove this from the detached plan list:
-    auto end = m_detached_plans.end();    
-    auto iter = std::find_if(m_detached_plans.begin(), end, 
-        [&] (ThreadPlanStack *elem) {
-          return elem == &stack; });
-    if (iter != end)
-      m_detached_plans.erase(iter);
-
-    if (m_plans_list.find(stack.GetTID()) == m_plans_list.end())
-      m_plans_list.emplace(stack.GetTID(), &stack);
-    else
-      m_plans_list.at(stack.GetTID()) = &stack;
-  }
-
-  void ScanForDetachedPlanStacks() {
-    std::lock_guard<std::recursive_mutex> guard(m_stack_map_mutex);
-    llvm::SmallVector<lldb::tid_t, 2> invalidated_tids;
-    for (auto &pair : m_plans_list)
-      if (pair.second->GetTID() != pair.first)
-        invalidated_tids.push_back(pair.first);
-
-    for (auto tid : invalidated_tids) {
-      auto it = m_plans_list.find(tid);
-      ThreadPlanStack *stack = it->second;
-      m_plans_list.erase(it);
-      m_detached_plans.push_back(stack);
-    }
-  }
-
-  // This gets the vector of pointers to thread plans that aren't
-  // currently running on a thread.  This is generally for thread
-  // plans that represent asynchronous operations waiting to be
-  // scheduled.
-  // The vector will never have null ThreadPlanStacks in it.
-  lldb::ThreadPlanSP FindThreadPlanInStack(
-      llvm::function_ref<lldb::ThreadPlanSP(ThreadPlanStack &)> fn) {
-    std::lock_guard<std::recursive_mutex> guard(m_stack_map_mutex);
-    for (auto *stack : m_detached_plans)
-      if (auto plan = fn(*stack))
-        return plan;
-    return {};
+      plan_list.second.ClearThreadCache();
   }
 
   void Clear() {
     std::lock_guard<std::recursive_mutex> guard(m_stack_map_mutex);
     for (auto &plan : m_plans_list)
-      plan.second->ThreadDestroyed(nullptr);
+      plan.second.ThreadDestroyed(nullptr);
     m_plans_list.clear();
   }
 
@@ -256,23 +181,8 @@ class ThreadPlanStackMap {
 
 private:
   Process &m_process;
-  // We don't want to make copies of these ThreadPlanStacks, there needs to be
-  // just one of these tracking each piece of work.  But we need to move the
-  // work from "attached to a TID" state to "detached" state, which is most
-  // conveniently done by having organizing containers for each of the two 
-  // states.
-  // To make it easy to move these non-copyable entities in and out of the
-  // organizing containers, we make the ThreadPlanStacks into unique_ptr's in a 
-  // storage container - m_plans_up_container.  Storing unique_ptrs means we
-  // can then use the pointer to the ThreadPlanStack in the "organizing"
-  // containers, the TID->Stack map m_plans_list, and the detached plans
-  // vector m_detached_plans.
-  
-  using PlansStore = std::vector<std::unique_ptr<ThreadPlanStack>>;
-  PlansStore m_plans_up_container;
-  std::vector<ThreadPlanStack *> m_detached_plans;
   mutable std::recursive_mutex m_stack_map_mutex;
-  using PlansList = std::unordered_map<lldb::tid_t, ThreadPlanStack *>;
+  using PlansList = std::unordered_map<lldb::tid_t, ThreadPlanStack>;
   PlansList m_plans_list;
 
 };

lldb/source/Target/Process.cpp

@@ -1373,34 +1373,6 @@ void Process::UpdateThreadListIfNeeded() {
   }
 }
 
-void Process::SynchronizeThreadPlans() {
-  m_thread_plans.ScanForDetachedPlanStacks();
-}
-
-ThreadPlanSP Process::FindDetachedPlanExplainingStop(Thread &thread,
-                                                     Event *event_ptr) {
-  return m_thread_plans.FindThreadPlanInStack(
-      [&](ThreadPlanStack &stack) -> ThreadPlanSP {
-        return DoesStackExplainStopNoLock(stack, thread, event_ptr);
-      });
-}
-
-// This extracted function only exists so that it can be marked a friend of
-// `ThreadPlan`, which is needed to call `DoPlanExplainsStop`.
-ThreadPlanSP Process::DoesStackExplainStopNoLock(ThreadPlanStack &stack,
-                                                 Thread &thread,
-                                                 Event *event_ptr) {
-  ThreadPlanSP plan_sp = stack.GetCurrentPlan();
-  plan_sp->SetTID(thread.GetID());
-  if (plan_sp->DoPlanExplainsStop(event_ptr)) {
-    stack.SetTID(thread.GetID());
-    m_thread_plans.Activate(stack);
-    return plan_sp;
-  }
-  plan_sp->ClearTID();
-  return {};
-}
-
 ThreadPlanStack *Process::FindThreadPlans(lldb::tid_t tid) {
   return m_thread_plans.Find(tid);
 }
@@ -3850,10 +3822,8 @@ bool Process::ShouldBroadcastEvent(Event *event_ptr) {
       // restarted... Asking the thread list is also not likely to go well,
       // since we are running again. So in that case just report the event.
 
-      if (!was_restarted) {
+      if (!was_restarted)
         should_resume = !m_thread_list.ShouldStop(event_ptr);
-        SynchronizeThreadPlans();
-      }
 
       if (was_restarted || should_resume || m_resume_requested) {
         Vote report_stop_vote = m_thread_list.ShouldReportStop(event_ptr);

lldb/source/Target/Thread.cpp

@@ -765,6 +765,7 @@ void Thread::DidResume() {
 void Thread::DidStop() { SetState(eStateStopped); }
 
 bool Thread::ShouldStop(Event *event_ptr) {
+  ThreadPlan *current_plan = GetCurrentPlan();
   bool should_stop = true;
 
   Log *log = GetLog(LLDBLog::Step);
@@ -818,6 +819,9 @@ bool Thread::ShouldStop(Event *event_ptr) {
     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
@@ -830,16 +834,6 @@ bool Thread::ShouldStop(Event *event_ptr) {
     return false;
   }
 
-  // Call this after ShouldStopSynchronous.
-  ThreadPlan *current_plan;
-  if (auto plan = GetProcess()->FindDetachedPlanExplainingStop(*this, event_ptr))
-    current_plan = plan.get();
-  else
-    current_plan = GetCurrentPlan();
-
-  // The top most plan always gets to do the trace log…
-  current_plan->DoTraceLog();
-
   // 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))
@@ -856,7 +850,6 @@ bool Thread::ShouldStop(Event *event_ptr) {
   // 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;

lldb/source/Target/ThreadPlanStack.cpp

@@ -409,13 +409,6 @@ void ThreadPlanStack::WillResume() {
   m_discarded_plans.clear();
 }
 
-lldb::tid_t ThreadPlanStack::GetTID() { return GetCurrentPlan()->GetTID(); }
-
-void ThreadPlanStack::SetTID(lldb::tid_t tid) {
-  for (auto plan_sp : m_plans)
-    plan_sp->SetTID(tid);
-}
-
 void ThreadPlanStackMap::Update(ThreadList &current_threads,
                                 bool delete_missing,
                                 bool check_for_new) {
@@ -469,8 +462,8 @@ void ThreadPlanStackMap::DumpPlans(Stream &strm,
       index_id = thread_sp->GetIndexID();
 
     if (condense_if_trivial) {
-      if (!elem.second->AnyPlans() && !elem.second->AnyCompletedPlans() &&
-          !elem.second->AnyDiscardedPlans()) {
+      if (!elem.second.AnyPlans() && !elem.second.AnyCompletedPlans() &&
+          !elem.second.AnyDiscardedPlans()) {
         strm.Printf("thread #%u: tid = 0x%4.4" PRIx64 "\n", index_id, tid);
         strm.IndentMore();
         strm.Indent();
@@ -483,7 +476,7 @@ void ThreadPlanStackMap::DumpPlans(Stream &strm,
     strm.Indent();
     strm.Printf("thread #%u: tid = 0x%4.4" PRIx64 ":\n", index_id, tid);
 
-    elem.second->DumpThreadPlans(strm, desc_level, internal);
+    elem.second.DumpThreadPlans(strm, desc_level, internal);
   }
 }