ref: 5b5f69513adcb9939e4ebd93bf8adfbfdc08fcf1 dir: /sys/src/libc/mips/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4