ref: a45dbe7a9a18a016081c5cd5492a42c8b0547f6a dir: /sys/src/libc/mips/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4