ref: 35cffbd08f2428ef2b9be2bc293aa4b345cf082a
dir: /sys/src/libc/amd64/main9p.s/
TEXT _mainp(SB), 1, $0 MOVQ AX, _tos(SB) MOVQ $_profmain(SB), RARG PUSHQ RARG PUSHQ $0 JMPF _callmain(SB) TEXT _savearg(SB), 1, $0 MOVQ RARG, AX RET TEXT _saveret(SB), 1, $0 RET /* we want RARG in RARG */ TEXT _callpc(SB), 1, $0 MOVQ 8(RARG), AX RET