Don't assume backing thread shares protocol ID.

When we're dealing with virtual (memory) threads created by the OS
plugins, there's no guarantee that the real thread and the backing
thread share a protocol ID. Instead, we should iterate over the memory
threads to find the virtual thread that is backed by the current real
thread.

Differential revision: https://reviews.llvm.org/D45497

rdar://36485830

llvm-svn: 329891

1 files changed, 14 insertions, 0 deletions

diff --git a/lldb/source/Target/ThreadList.cpp b/lldb/source/Target/ThreadList.cpp
index 4cf8f9061a8..61483914644 100644
--- a/lldb/source/Target/ThreadList.cpp
+++ b/lldb/source/Target/ThreadList.cpp
@@ -195,6 +195,20 @@ ThreadSP ThreadList::GetThreadSPForThreadPtr(Thread *thread_ptr) {
   return thread_sp;
 }
 
+ThreadSP ThreadList::GetBackingThread(const ThreadSP &real_thread) {
+  std::lock_guard<std::recursive_mutex> guard(GetMutex());
+
+  ThreadSP thread_sp;
+  const uint32_t num_threads = m_threads.size();
+  for (uint32_t idx = 0; idx < num_threads; ++idx) {
+    if (m_threads[idx]->GetBackingThread() == real_thread) {
+      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());