This is xnu-8019. See this file in:
Directory listing for xnu-8019//osfmk/arm64
Makefile
WKdmCompress_16k.s
WKdmCompress_4k.s
WKdmData.s
WKdmDecompress_16k.s
WKdmDecompress_4k.s
alternate_debugger.c
alternate_debugger.h
alternate_debugger_asm.s
amcc_rorgn.h
arm_vm_init.c
asm.h
bcopy.s
bsd_arm64.c
bzero.s
caches_asm.s
copyio.c
corecrypto/
cpu.c
cswitch.s
dbgwrap.c
dwarf_unwind.h
exception_asm.h
genassym.c
gxf_exceptions.s
hibernate_arm64.c
hibernate_ppl_hmac.c
hibernate_ppl_hmac.h
hibernate_restore.c
instructions.h
locore.s
loose_ends.c
lowglobals.h
lowmem_vectors.c
lz4_decode_arm64.s
lz4_encode_arm64.s
machine_cpuid.h
machine_kpc.h
machine_machdep.h
machine_remote_time.c
machine_remote_time.h
machine_routines.c
machine_routines_asm.h
machine_routines_asm.s
machine_task.c
memcmp_zero.s
monotonic.h
monotonic_arm64.c
pac_asm.h
pal_hibernate.h
pcb.c
perfmon_arm64.c
perfmon_arm64_regs.h
pinst.s
platform_tests.c
platform_tests_asm.s
proc_reg.h
serror_handler.c
serror_handler.h
sleh.c
smccc_asm.h
start.s
status.c
strncmp.s
strnlen.s
tlb.h