CodeGen/CIRGenBuiltin.cpp:  case Builtin::BI__atomic_thread_fence:
CodeGen/CIRGenBuiltin.cpp-  case Builtin::BI__atomic_signal_fence:
CodeGen/CIRGenBuiltin.cpp:  case Builtin::BI__c11_atomic_thread_fence:
CodeGen/CIRGenBuiltin.cpp-  case Builtin::BI__c11_atomic_signal_fence:
CodeGen/CIRGenBuiltin.cpp:    llvm_unreachable("BI__atomic_thread_fence like NYI");