This is xnu-8019. See this file in:
Directory listing for xnu-8019//iokit/DriverKit
IOBufferMemoryDescriptor.iig
IODMACommand.iig
IODataQueueDispatchSource.iig
IODispatchQueue.iig
IODispatchSource.iig
IOEventLink.iig
IOInterruptDispatchSource.iig
IOKernelReportStructs.h
IOKitKeys.h
IOMemoryDescriptor.iig
IOMemoryMap.iig
IORPC.h
IOReportTypes.h
IOReturn.h
IOService.iig
IOServiceNotificationDispatchSource.iig
IOServiceStateNotificationDispatchSource.iig
IOTypes.h
IOUserClient.iig
IOUserServer.iig
IOWorkGroup.iig
Makefile
OSAction.iig
OSBoundedArray.h
OSBoundedArrayRef.h
OSBoundedPtr.h
OSBoundedPtrFwd.h
OSObject.iig
bounded_array.h
bounded_array_ref.h
bounded_ptr.h
bounded_ptr_fwd.h
crypto/
macro_help.h
queue_implementation.h
safe_allocation.h