ref: a8fbcf42a84c259e7b26033ea5349ad78f33e5d6 dir: /sys/src/libc/amd64/main9.s/
TEXT _main(SB), 1, $0 MOVQ AX, _tos(SB) MOVQ $main(SB), RARG PUSHQ RARG PUSHQ $0 JMPF _callmain(SB)