pt_fpregs
{ "$x", "?", "print floating point registers", pt_fpregs },
{ "$X", "?", "print floating point registers", pt_fpregs },
{ "$y", "?", "print floating point registers", pt_fpregs },
{ "$Y", "?", "print floating point registers", pt_fpregs },
{ "fpregs", "?[-dqs]", "print floating point registers", pt_fpregs },
extern int pt_fpregs(uintptr_t, uint_t, int, const mdb_arg_t *);