ref: b3e06559475b0130a7a2fb56ac4d131d13d2012f dir: /sys/src/ape/lib/ap/arm64/main9.s/
GLOBL _tos(SB), $8 TEXT _main(SB), 1, $0 SUB $16, SP MOV $setSB(SB), R28 MOV R0, _tos(SB) MOV $_apemain(SB), R0 MOV $0, R30 B _callmain(SB)