ref: e391b7ec8c0dc746a70725f3fc598def0419d1e6 dir: /sys/src/ape/lib/ap/riscv64/argv0.s/
GLOBL argv0(SB), $XLEN GLOBL _tos(SB), $XLEN GLOBL _privates(SB), $XLEN GLOBL _nprivates(SB), $4