ref: 5ff1ec275223dc782ec8be5d219d7d3c7f53c2a9 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)