ref: 031f5756aba3d07939a7eee6b2adf02f0a2d1d8d dir: /sys/src/libc/arm64/argv0.s/
GLOBL argv0(SB), $8 GLOBL _tos(SB), $8 GLOBL _privates(SB), $8 GLOBL _nprivates(SB), $4