ref: 1fe3143e4c43ce2c74e0cfdd70b1bd556bbb9e1b dir: /sys/src/libc/mips/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4