ref: 6abe569ec8f47ba14c3dcd5d5214e7b7a020bf7a dir: /sys/src/libc/arm64/argv0.s/
GLOBL argv0(SB), $8 GLOBL _tos(SB), $8 GLOBL _privates(SB), $8 GLOBL _nprivates(SB), $4