ref: 8ebe3f680e9f343a13bfcaaa2e17745b701ec0c8 dir: /sys/src/libc/mips/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4