This is xnu-8019. See this file in:
# libIOKit

iokit/Kernel/IOSyncer.cpp				optional iokitcpp

iokit/Kernel/x86_64/IOAsmSupport.s                            standard

# Power Domains
iokit/Kernel/IOPMrootDomain.cpp    			    optional iokitcpp

# Key Store helper
iokit/Kernel/i386/IOKeyStoreHelper.cpp			    standard