ref: 67970c4c6bdaed7fb0b6e6a22f77f23a7acd2f0a dir: /sys/src/libc/arm64/argv0.s/
GLOBL argv0(SB), $8 GLOBL _tos(SB), $8 GLOBL _privates(SB), $8 GLOBL _nprivates(SB), $4