Merge "Reserve bits in the lock word for read barriers."

diff --cc runtime/arch/arm/quick_entrypoints_arm.S
Simple merge

diff --cc runtime/arch/arm64/quick_entrypoints_arm64.S
Simple merge

diff --cc runtime/arch/x86/quick_entrypoints_x86.S
Simple merge

diff --cc runtime/arch/x86_64/quick_entrypoints_x86_64.S
Simple merge

diff --cc runtime/thread_list.cc
index 31ccbcc,7c0e7d7..d4c1e8c
--- 1/runtime/thread_list.cc
--- 2/runtime/thread_list.cc
+++ b/runtime/thread_list.cc
@@@ -51,9 -51,10 +51,9 @@@ static constexpr useconds_t kThreadSusp
  static constexpr useconds_t kThreadSuspendMaxSleepUs = 5000;
  
  ThreadList::ThreadList()
 -    : suspend_all_count_(0), debug_suspend_all_count_(0),
 -      thread_exit_cond_("thread exit condition variable", *Locks::thread_list_lock_),
 +    : suspend_all_count_(0), debug_suspend_all_count_(0), unregistering_count_(0),
        suspend_all_historam_("suspend all histogram", 16, 64) {
-   CHECK(Monitor::IsValidLockWord(LockWord::FromThinLockId(kMaxThreadId, 1)));
+   CHECK(Monitor::IsValidLockWord(LockWord::FromThinLockId(kMaxThreadId, 1, 0U)));
  }
  
  ThreadList::~ThreadList() {