imag
    (Store {typ.Float64} dst real mem))

// string ops
(StringPtr (StringMake ptr _)) => ptr
(StringLen (StringMake _ len)) => len

(Load <t> ptr mem) && t.IsString() =>
  (StringMake
    (Load <typ.BytePtr> ptr mem)
    (Load <typ.Int>
      (OffPtr <typ.IntPtr> [config.PtrSize] ptr)
      mem))
(Store dst (StringMake ptr len) mem) =>
  (Store {typ.Int}
    (OffPtr <typ.IntPtr> [config.PtrSize] dst)
    len