This is xnu-8019. See this file in:
Directory listing for xnu-8019//bsd
Makefile
arm/
bsm/
conf/
crypto/
dev/
i386/
kern/
libkern/
machine/
man/
miscfs/
net/
netinet/
netinet6/
netkey/
nfs/
pgo/
pthread/
security/
skywalk/
sys/
tests/
uuid/
uxkern/
vfs/
vm/