ref: 61a7e15cb1ddb7b08f9bcbdb035e39af3d6a5e8d dir: /sys/src/libc/mips/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4