ref: e1cc6a9a0f0ebbcbb32f177cfc2c977509cbb6fb dir: /sys/src/libc/mips/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4