ref: 23620bb1dbbf80f07a156d3f1fe1e74d5f4d61ba dir: /sys/src/libc/arm64/argv0.s/
GLOBL argv0(SB), $8 GLOBL _tos(SB), $8 GLOBL _privates(SB), $8 GLOBL _nprivates(SB), $4