llvm-project/lldb/source/Target/ThreadList.cpp

761 lines
24 KiB
C++

//===-- ThreadList.cpp ------------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// C Includes
#include <stdlib.h>
// C++ Includes
#include <algorithm>
// Other libraries and framework includes
// Project includes
#include "lldb/Core/State.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/Thread.h"
#include "lldb/Target/ThreadList.h"
#include "lldb/Target/ThreadPlan.h"
#include "lldb/Utility/LLDBAssert.h"
#include "lldb/Utility/Log.h"
using namespace lldb;
using namespace lldb_private;
ThreadList::ThreadList(Process *process)
: ThreadCollection(), m_process(process), m_stop_id(0),
m_selected_tid(LLDB_INVALID_THREAD_ID) {}
ThreadList::ThreadList(const ThreadList &rhs)
: ThreadCollection(), m_process(rhs.m_process), m_stop_id(rhs.m_stop_id),
m_selected_tid() {
// Use the assignment operator since it uses the mutex
*this = rhs;
}
const ThreadList &ThreadList::operator=(const ThreadList &rhs) {
if (this != &rhs) {
// Lock both mutexes to make sure neither side changes anyone on us
// while the assignment occurs
std::lock_guard<std::recursive_mutex> guard(GetMutex());
std::lock_guard<std::recursive_mutex> rhs_guard(rhs.GetMutex());
m_process = rhs.m_process;
m_stop_id = rhs.m_stop_id;
m_threads = rhs.m_threads;
m_selected_tid = rhs.m_selected_tid;
}
return *this;
}
ThreadList::~ThreadList() {
// Clear the thread list. Clear will take the mutex lock
// which will ensure that if anyone is using the list
// they won't get it removed while using it.
Clear();
}
lldb::ThreadSP ThreadList::GetExpressionExecutionThread() {
if (m_expression_tid_stack.empty())
return GetSelectedThread();
ThreadSP expr_thread_sp = FindThreadByID(m_expression_tid_stack.back());
if (expr_thread_sp)
return expr_thread_sp;
else
return GetSelectedThread();
}
void ThreadList::PushExpressionExecutionThread(lldb::tid_t tid) {
m_expression_tid_stack.push_back(tid);
}
void ThreadList::PopExpressionExecutionThread(lldb::tid_t tid) {
assert(m_expression_tid_stack.back() == tid);
m_expression_tid_stack.pop_back();
}
uint32_t ThreadList::GetStopID() const { return m_stop_id; }
void ThreadList::SetStopID(uint32_t stop_id) { m_stop_id = stop_id; }
uint32_t ThreadList::GetSize(bool can_update) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
if (can_update)
m_process->UpdateThreadListIfNeeded();
return m_threads.size();
}
ThreadSP ThreadList::GetThreadAtIndex(uint32_t idx, bool can_update) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
if (can_update)
m_process->UpdateThreadListIfNeeded();
ThreadSP thread_sp;
if (idx < m_threads.size())
thread_sp = m_threads[idx];
return thread_sp;
}
ThreadSP ThreadList::FindThreadByID(lldb::tid_t tid, bool can_update) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
if (can_update)
m_process->UpdateThreadListIfNeeded();
ThreadSP thread_sp;
uint32_t idx = 0;
const uint32_t num_threads = m_threads.size();
for (idx = 0; idx < num_threads; ++idx) {
if (m_threads[idx]->GetID() == tid) {
thread_sp = m_threads[idx];
break;
}
}
return thread_sp;
}
ThreadSP ThreadList::FindThreadByProtocolID(lldb::tid_t tid, bool can_update) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
if (can_update)
m_process->UpdateThreadListIfNeeded();
ThreadSP thread_sp;
uint32_t idx = 0;
const uint32_t num_threads = m_threads.size();
for (idx = 0; idx < num_threads; ++idx) {
if (m_threads[idx]->GetProtocolID() == tid) {
thread_sp = m_threads[idx];
break;
}
}
return thread_sp;
}
ThreadSP ThreadList::RemoveThreadByID(lldb::tid_t tid, bool can_update) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
if (can_update)
m_process->UpdateThreadListIfNeeded();
ThreadSP thread_sp;
uint32_t idx = 0;
const uint32_t num_threads = m_threads.size();
for (idx = 0; idx < num_threads; ++idx) {
if (m_threads[idx]->GetID() == tid) {
thread_sp = m_threads[idx];
m_threads.erase(m_threads.begin() + idx);
break;
}
}
return thread_sp;
}
ThreadSP ThreadList::RemoveThreadByProtocolID(lldb::tid_t tid,
bool can_update) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
if (can_update)
m_process->UpdateThreadListIfNeeded();
ThreadSP thread_sp;
uint32_t idx = 0;
const uint32_t num_threads = m_threads.size();
for (idx = 0; idx < num_threads; ++idx) {
if (m_threads[idx]->GetProtocolID() == tid) {
thread_sp = m_threads[idx];
m_threads.erase(m_threads.begin() + idx);
break;
}
}
return thread_sp;
}
ThreadSP ThreadList::GetThreadSPForThreadPtr(Thread *thread_ptr) {
ThreadSP thread_sp;
if (thread_ptr) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
uint32_t idx = 0;
const uint32_t num_threads = m_threads.size();
for (idx = 0; idx < num_threads; ++idx) {
if (m_threads[idx].get() == thread_ptr) {
thread_sp = m_threads[idx];
break;
}
}
}
return thread_sp;
}
ThreadSP ThreadList::FindThreadByIndexID(uint32_t index_id, bool can_update) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
if (can_update)
m_process->UpdateThreadListIfNeeded();
ThreadSP thread_sp;
const uint32_t num_threads = m_threads.size();
for (uint32_t idx = 0; idx < num_threads; ++idx) {
if (m_threads[idx]->GetIndexID() == index_id) {
thread_sp = m_threads[idx];
break;
}
}
return thread_sp;
}
bool ThreadList::ShouldStop(Event *event_ptr) {
// Running events should never stop, obviously...
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
// The ShouldStop method of the threads can do a whole lot of work,
// figuring out whether the thread plan conditions are met. So we don't want
// to keep the ThreadList locked the whole time we are doing this.
// FIXME: It is possible that running code could cause new threads
// to be created. If that happens, we will miss asking them whether
// they should stop. This is not a big deal since we haven't had
// a chance to hang any interesting operations on those threads yet.
collection threads_copy;
{
// Scope for locker
std::lock_guard<std::recursive_mutex> guard(GetMutex());
m_process->UpdateThreadListIfNeeded();
for (lldb::ThreadSP thread_sp : m_threads) {
// This is an optimization... If we didn't let a thread run in between
// the previous stop and this
// one, we shouldn't have to consult it for ShouldStop. So just leave it
// off the list we are going to
// inspect.
// On Linux, if a thread-specific conditional breakpoint was hit, it won't
// necessarily be the thread
// that hit the breakpoint itself that evaluates the conditional
// expression, so the thread that hit
// the breakpoint could still be asked to stop, even though it hasn't been
// allowed to run since the
// previous stop.
if (thread_sp->GetTemporaryResumeState() != eStateSuspended ||
thread_sp->IsStillAtLastBreakpointHit())
threads_copy.push_back(thread_sp);
}
// It is possible the threads we were allowing to run all exited and then
// maybe the user interrupted
// or something, then fall back on looking at all threads:
if (threads_copy.size() == 0)
threads_copy = m_threads;
}
collection::iterator pos, end = threads_copy.end();
if (log) {
log->PutCString("");
log->Printf("ThreadList::%s: %" PRIu64 " threads, %" PRIu64
" unsuspended threads",
__FUNCTION__, (uint64_t)m_threads.size(),
(uint64_t)threads_copy.size());
}
bool did_anybody_stop_for_a_reason = false;
// If the event is an Interrupt event, then we're going to stop no matter
// what. Otherwise, presume we won't stop.
bool should_stop = false;
if (Process::ProcessEventData::GetInterruptedFromEvent(event_ptr)) {
if (log)
log->Printf(
"ThreadList::%s handling interrupt event, should stop set to true",
__FUNCTION__);
should_stop = true;
}
// Now we run through all the threads and get their stop info's. We want to
// make sure to do this first before
// we start running the ShouldStop, because one thread's ShouldStop could
// destroy information (like deleting a
// thread specific breakpoint another thread had stopped at) which could lead
// us to compute the StopInfo incorrectly.
// We don't need to use it here, we just want to make sure it gets computed.
for (pos = threads_copy.begin(); pos != end; ++pos) {
ThreadSP thread_sp(*pos);
thread_sp->GetStopInfo();
}
for (pos = threads_copy.begin(); pos != end; ++pos) {
ThreadSP thread_sp(*pos);
// We should never get a stop for which no thread had a stop reason, but
// sometimes we do see this -
// for instance when we first connect to a remote stub. In that case we
// should stop, since we can't figure out
// the right thing to do and stopping gives the user control over what to do
// in this instance.
//
// Note, this causes a problem when you have a thread specific breakpoint,
// and a bunch of threads hit the breakpoint,
// but not the thread which we are waiting for. All the threads that are
// not "supposed" to hit the breakpoint
// are marked as having no stop reason, which is right, they should not show
// a stop reason. But that triggers this
// code and causes us to stop seemingly for no reason.
//
// Since the only way we ever saw this error was on first attach, I'm only
// going to trigger set did_anybody_stop_for_a_reason
// to true unless this is the first stop.
//
// If this becomes a problem, we'll have to have another StopReason like
// "StopInfoHidden" which will look invalid
// everywhere but at this check.
if (thread_sp->GetProcess()->GetStopID() > 1)
did_anybody_stop_for_a_reason = true;
else
did_anybody_stop_for_a_reason |= thread_sp->ThreadStoppedForAReason();
const bool thread_should_stop = thread_sp->ShouldStop(event_ptr);
if (thread_should_stop)
should_stop |= true;
}
if (!should_stop && !did_anybody_stop_for_a_reason) {
should_stop = true;
if (log)
log->Printf("ThreadList::%s we stopped but no threads had a stop reason, "
"overriding should_stop and stopping.",
__FUNCTION__);
}
if (log)
log->Printf("ThreadList::%s overall should_stop = %i", __FUNCTION__,
should_stop);
if (should_stop) {
for (pos = threads_copy.begin(); pos != end; ++pos) {
ThreadSP thread_sp(*pos);
thread_sp->WillStop();
}
}
return should_stop;
}
Vote ThreadList::ShouldReportStop(Event *event_ptr) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
Vote result = eVoteNoOpinion;
m_process->UpdateThreadListIfNeeded();
collection::iterator pos, end = m_threads.end();
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
if (log)
log->Printf("ThreadList::%s %" PRIu64 " threads", __FUNCTION__,
(uint64_t)m_threads.size());
// Run through the threads and ask whether we should report this event.
// For stopping, a YES vote wins over everything. A NO vote wins over NO
// opinion.
for (pos = m_threads.begin(); pos != end; ++pos) {
ThreadSP thread_sp(*pos);
const Vote vote = thread_sp->ShouldReportStop(event_ptr);
switch (vote) {
case eVoteNoOpinion:
continue;
case eVoteYes:
result = eVoteYes;
break;
case eVoteNo:
if (result == eVoteNoOpinion) {
result = eVoteNo;
} else {
LLDB_LOG(log,
"Thread {0:x} voted {1}, but lost out because result was {2}",
thread_sp->GetID(), vote, result);
}
break;
}
}
LLDB_LOG(log, "Returning {0}", result);
return result;
}
void ThreadList::SetShouldReportStop(Vote vote) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
m_process->UpdateThreadListIfNeeded();
collection::iterator pos, end = m_threads.end();
for (pos = m_threads.begin(); pos != end; ++pos) {
ThreadSP thread_sp(*pos);
thread_sp->SetShouldReportStop(vote);
}
}
Vote ThreadList::ShouldReportRun(Event *event_ptr) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
Vote result = eVoteNoOpinion;
m_process->UpdateThreadListIfNeeded();
collection::iterator pos, end = m_threads.end();
// Run through the threads and ask whether we should report this event.
// The rule is NO vote wins over everything, a YES vote wins over no opinion.
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
for (pos = m_threads.begin(); pos != end; ++pos) {
if ((*pos)->GetResumeState() != eStateSuspended) {
switch ((*pos)->ShouldReportRun(event_ptr)) {
case eVoteNoOpinion:
continue;
case eVoteYes:
if (result == eVoteNoOpinion)
result = eVoteYes;
break;
case eVoteNo:
if (log)
log->Printf("ThreadList::ShouldReportRun() thread %d (0x%4.4" PRIx64
") says don't report.",
(*pos)->GetIndexID(), (*pos)->GetID());
result = eVoteNo;
break;
}
}
}
return result;
}
void ThreadList::Clear() {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
m_stop_id = 0;
m_threads.clear();
m_selected_tid = LLDB_INVALID_THREAD_ID;
}
void ThreadList::Destroy() {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
const uint32_t num_threads = m_threads.size();
for (uint32_t idx = 0; idx < num_threads; ++idx) {
m_threads[idx]->DestroyThread();
}
}
void ThreadList::RefreshStateAfterStop() {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
m_process->UpdateThreadListIfNeeded();
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
if (log && log->GetVerbose())
log->Printf("Turning off notification of new threads while single stepping "
"a thread.");
collection::iterator pos, end = m_threads.end();
for (pos = m_threads.begin(); pos != end; ++pos)
(*pos)->RefreshStateAfterStop();
}
void ThreadList::DiscardThreadPlans() {
// You don't need to update the thread list here, because only threads
// that you currently know about have any thread plans.
std::lock_guard<std::recursive_mutex> guard(GetMutex());
collection::iterator pos, end = m_threads.end();
for (pos = m_threads.begin(); pos != end; ++pos)
(*pos)->DiscardThreadPlans(true);
}
bool ThreadList::WillResume() {
// Run through the threads and perform their momentary actions.
// But we only do this for threads that are running, user suspended
// threads stay where they are.
std::lock_guard<std::recursive_mutex> guard(GetMutex());
m_process->UpdateThreadListIfNeeded();
collection::iterator pos, end = m_threads.end();
// See if any thread wants to run stopping others. If it does, then we won't
// setup the other threads for resume, since they aren't going to get a chance
// to run. This is necessary because the SetupForResume might add
// "StopOthers"
// plans which would then get to be part of the who-gets-to-run negotiation,
// but
// they're coming in after the fact, and the threads that are already set up
// should
// take priority.
bool wants_solo_run = false;
for (pos = m_threads.begin(); pos != end; ++pos) {
lldbassert((*pos)->GetCurrentPlan() &&
"thread should not have null thread plan");
if ((*pos)->GetResumeState() != eStateSuspended &&
(*pos)->GetCurrentPlan()->StopOthers()) {
if ((*pos)->IsOperatingSystemPluginThread() &&
!(*pos)->GetBackingThread())
continue;
wants_solo_run = true;
break;
}
}
if (wants_solo_run) {
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
if (log && log->GetVerbose())
log->Printf("Turning on notification of new threads while single "
"stepping a thread.");
m_process->StartNoticingNewThreads();
} else {
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
if (log && log->GetVerbose())
log->Printf("Turning off notification of new threads while single "
"stepping a thread.");
m_process->StopNoticingNewThreads();
}
// Give all the threads that are likely to run a last chance to set up their
// state before we
// negotiate who is actually going to get a chance to run...
// Don't set to resume suspended threads, and if any thread wanted to stop
// others, only
// call setup on the threads that request StopOthers...
for (pos = m_threads.begin(); pos != end; ++pos) {
if ((*pos)->GetResumeState() != eStateSuspended &&
(!wants_solo_run || (*pos)->GetCurrentPlan()->StopOthers())) {
if ((*pos)->IsOperatingSystemPluginThread() &&
!(*pos)->GetBackingThread())
continue;
(*pos)->SetupForResume();
}
}
// Now go through the threads and see if any thread wants to run just itself.
// if so then pick one and run it.
ThreadList run_me_only_list(m_process);
run_me_only_list.SetStopID(m_process->GetStopID());
bool run_only_current_thread = false;
for (pos = m_threads.begin(); pos != end; ++pos) {
ThreadSP thread_sp(*pos);
if (thread_sp->GetResumeState() != eStateSuspended &&
thread_sp->GetCurrentPlan()->StopOthers()) {
if ((*pos)->IsOperatingSystemPluginThread() &&
!(*pos)->GetBackingThread())
continue;
// You can't say "stop others" and also want yourself to be suspended.
assert(thread_sp->GetCurrentPlan()->RunState() != eStateSuspended);
if (thread_sp == GetSelectedThread()) {
// If the currently selected thread wants to run on its own, always let
// it.
run_only_current_thread = true;
run_me_only_list.Clear();
run_me_only_list.AddThread(thread_sp);
break;
}
run_me_only_list.AddThread(thread_sp);
}
}
bool need_to_resume = true;
if (run_me_only_list.GetSize(false) == 0) {
// Everybody runs as they wish:
for (pos = m_threads.begin(); pos != end; ++pos) {
ThreadSP thread_sp(*pos);
StateType run_state;
if (thread_sp->GetResumeState() != eStateSuspended)
run_state = thread_sp->GetCurrentPlan()->RunState();
else
run_state = eStateSuspended;
if (!thread_sp->ShouldResume(run_state))
need_to_resume = false;
}
} else {
ThreadSP thread_to_run;
if (run_only_current_thread) {
thread_to_run = GetSelectedThread();
} else if (run_me_only_list.GetSize(false) == 1) {
thread_to_run = run_me_only_list.GetThreadAtIndex(0);
} else {
int random_thread =
(int)((run_me_only_list.GetSize(false) * (double)rand()) /
(RAND_MAX + 1.0));
thread_to_run = run_me_only_list.GetThreadAtIndex(random_thread);
}
for (pos = m_threads.begin(); pos != end; ++pos) {
ThreadSP thread_sp(*pos);
if (thread_sp == thread_to_run) {
if (!thread_sp->ShouldResume(thread_sp->GetCurrentPlan()->RunState()))
need_to_resume = false;
} else
thread_sp->ShouldResume(eStateSuspended);
}
}
return need_to_resume;
}
void ThreadList::DidResume() {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
collection::iterator pos, end = m_threads.end();
for (pos = m_threads.begin(); pos != end; ++pos) {
// Don't clear out threads that aren't going to get a chance to run, rather
// leave their state for the next time around.
ThreadSP thread_sp(*pos);
if (thread_sp->GetResumeState() != eStateSuspended)
thread_sp->DidResume();
}
}
void ThreadList::DidStop() {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
collection::iterator pos, end = m_threads.end();
for (pos = m_threads.begin(); pos != end; ++pos) {
// Notify threads that the process just stopped.
// Note, this currently assumes that all threads in the list
// stop when the process stops. In the future we will want to support
// a debugging model where some threads continue to run while others
// are stopped. We either need to handle that somehow here or
// create a special thread list containing only threads which will
// stop in the code that calls this method (currently
// Process::SetPrivateState).
ThreadSP thread_sp(*pos);
if (StateIsRunningState(thread_sp->GetState()))
thread_sp->DidStop();
}
}
ThreadSP ThreadList::GetSelectedThread() {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
ThreadSP thread_sp = FindThreadByID(m_selected_tid);
if (!thread_sp.get()) {
if (m_threads.size() == 0)
return thread_sp;
m_selected_tid = m_threads[0]->GetID();
thread_sp = m_threads[0];
}
return thread_sp;
}
bool ThreadList::SetSelectedThreadByID(lldb::tid_t tid, bool notify) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
ThreadSP selected_thread_sp(FindThreadByID(tid));
if (selected_thread_sp) {
m_selected_tid = tid;
selected_thread_sp->SetDefaultFileAndLineToSelectedFrame();
} else
m_selected_tid = LLDB_INVALID_THREAD_ID;
if (notify)
NotifySelectedThreadChanged(m_selected_tid);
return m_selected_tid != LLDB_INVALID_THREAD_ID;
}
bool ThreadList::SetSelectedThreadByIndexID(uint32_t index_id, bool notify) {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
ThreadSP selected_thread_sp(FindThreadByIndexID(index_id));
if (selected_thread_sp.get()) {
m_selected_tid = selected_thread_sp->GetID();
selected_thread_sp->SetDefaultFileAndLineToSelectedFrame();
} else
m_selected_tid = LLDB_INVALID_THREAD_ID;
if (notify)
NotifySelectedThreadChanged(m_selected_tid);
return m_selected_tid != LLDB_INVALID_THREAD_ID;
}
void ThreadList::NotifySelectedThreadChanged(lldb::tid_t tid) {
ThreadSP selected_thread_sp(FindThreadByID(tid));
if (selected_thread_sp->EventTypeHasListeners(
Thread::eBroadcastBitThreadSelected))
selected_thread_sp->BroadcastEvent(
Thread::eBroadcastBitThreadSelected,
new Thread::ThreadEventData(selected_thread_sp));
}
void ThreadList::Update(ThreadList &rhs) {
if (this != &rhs) {
// Lock both mutexes to make sure neither side changes anyone on us
// while the assignment occurs
std::lock_guard<std::recursive_mutex> guard(GetMutex());
m_process = rhs.m_process;
m_stop_id = rhs.m_stop_id;
m_threads.swap(rhs.m_threads);
m_selected_tid = rhs.m_selected_tid;
// Now we look for threads that we are done with and
// make sure to clear them up as much as possible so
// anyone with a shared pointer will still have a reference,
// but the thread won't be of much use. Using std::weak_ptr
// for all backward references (such as a thread to a process)
// will eventually solve this issue for us, but for now, we
// need to work around the issue
collection::iterator rhs_pos, rhs_end = rhs.m_threads.end();
for (rhs_pos = rhs.m_threads.begin(); rhs_pos != rhs_end; ++rhs_pos) {
const lldb::tid_t tid = (*rhs_pos)->GetID();
bool thread_is_alive = false;
const uint32_t num_threads = m_threads.size();
for (uint32_t idx = 0; idx < num_threads; ++idx) {
ThreadSP backing_thread = m_threads[idx]->GetBackingThread();
if (m_threads[idx]->GetID() == tid ||
(backing_thread && backing_thread->GetID() == tid)) {
thread_is_alive = true;
break;
}
}
if (!thread_is_alive)
(*rhs_pos)->DestroyThread();
}
}
}
void ThreadList::Flush() {
std::lock_guard<std::recursive_mutex> guard(GetMutex());
collection::iterator pos, end = m_threads.end();
for (pos = m_threads.begin(); pos != end; ++pos)
(*pos)->Flush();
}
std::recursive_mutex &ThreadList::GetMutex() const {
return m_process->m_thread_mutex;
}
ThreadList::ExpressionExecutionThreadPusher::ExpressionExecutionThreadPusher(
lldb::ThreadSP thread_sp)
: m_thread_list(nullptr), m_tid(LLDB_INVALID_THREAD_ID) {
if (thread_sp) {
m_tid = thread_sp->GetID();
m_thread_list = &thread_sp->GetProcess()->GetThreadList();
m_thread_list->PushExpressionExecutionThread(m_tid);
}
}