ref: a74c7ca5ea3290dd55c6f2a03aa7c3bcd22d3f61 dir: /sys/src/libc/power64/main9.s/
TEXT _main(SB), 1, $-8 ADD $-16, R1 MOVD $0, R0 MOVD $setSB(SB), R2 MOVD R3, _tos(SB) MOVD $main(SB), R3 MOVD R0, LR MOVD $_callmain(SB), R4 MOVD R4, CTR BR (CTR)