(** 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.        (**r [0x4330_0000] *)

Lemma from_words_value:
forall x,
B2R _ _ (from_words ox4330_0000 x) = (bpow radix2 52 + Z2R (Int.unsigned x))%R
/\ is_finite _ _ (from_words ox4330_0000 x) = true
/\ Bsign _ _ (from_words ox4330_0000 x) = false.