ref: 2d4a2c5c2065a32b6b5bd6a0e887af1574a8dfec dir: /sys/src/libc/arm/argv0.s/
GLOBL argv0(SB), $4 GLOBL _tos(SB), $4 GLOBL _privates(SB), $4 GLOBL _nprivates(SB), $4