ref: f2f46f4a33ee9ccb4f0475163408b8a699ec4f7f dir: /sys/src/libc/mips/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4