ref: c325c491f61696e81ab0ee9e6aea840c3636ed3d dir: /sys/src/libc/power/main9.s/
TEXT _main(SB), 1, $0 SUB $8, R1 MOVW $setSB(SB), R2 MOVW R3, _tos(SB) MOVW $main(SB), R3 MOVW R0, LR MOVW $_callmain(SB), R4 MOVW R4, CTR BR (CTR)