(** Conversions from ints to floats can be defined as bitwise manipulations
  over the in-memory representation.  This is what the PowerPC port does.
  The trick is that [from_words 0x4330_0000 x] is the float
  [2^52 + of_intu x]. *)

Definition ox4330_0000 := Int.repr 1127219200.

Theorem of_int_from_words: forall x, of_int x = sub (from_words ox4330_0000 (Int.add x ox8000_0000)) (from_words ox4330_0000 ox8000_0000).