ref: 8e9d2434e97fe6cf4b0d3e7f43e3e35d7ae1033f dir: /sys/src/libc/mips/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4