ref: 66cc3768c1a4d898bd0fbf9f2e5cde7779d3ef9b dir: /sys/src/libc/amd64/argv0.s/
GLOBL argv0(SB), $8 GLOBL _tos(SB), $8 GLOBL _privates(SB), $8 GLOBL _nprivates(SB), $4