ref: 6769178e6344a35a7d85609a2586c3fe85c7f5e6 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)