ref: 6f3dfb57eba2eb9ab21e4a0d06c8415cccf45fb1 dir: /sys/src/libc/mips/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4