ref: 7aceac32e8fae763634f28cfccd9ce2356fccab5
dir: /sys/src/ape/lib/ap/power/main9.s/
GLOBL _tos(SB), $4 TEXT _main(SB), 1, $0 SUB $8, R1 MOVW $setSB(SB), R2 MOVW R3, _tos(SB) MOVW $_apemain(SB), R3 MOVW R0, LR MOVW $_callmain(SB), R4 MOVW R4, CTR BR (CTR)