This is xnu-4903.221.2. See this file in:
XY0stackshot_in_flags00stackshot_in_pid30system_state_flags	"		@	Darwin Kernel Version 18.0.0: Thu Jun 21 09:28:12 PDT 2018; root:xnu_development-4903.200.261.Zd90f885fb3d01936e8bdf37f5b4b7e05~1/DEVELOPMENT_ARM64_T8020	Pdebug=0x14e serial=3 amfi_get_out_of_my_way=1 launchctl_enforce_codesign=0 2}35	53C-o	 3		3,[TA3stackshot%	 @&	N\\@\LEo  h!@h!h!h!i!@i! i!j!@j!j!j!k!@k!i!k!l!@l!l!l!m!@m!k!#u[,g!@g!m!g!p!@!		!ۛ(!5	5	//^(		@stackshot_test_thread	 ӛ(P		M0
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