ref: ed0e438a3b1dad94a071bcbf3b6e1aa9a288e8c4 dir: /sys/src/libc/mips/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4