[RFC] Check number of uses in simplify_cond_using_ranges().

[Eric Botcazou]

> Is VRP the right pass to do this optimisation or should a later
> pass rather attempt to eliminate the new use of b_5 instead?  Uli
> has brought up the idea a mini "sign extend elimination" pass that
> checks if the result of a sign extend could be replaced by the
> original quantity in all places, and if so, eliminate the ssa
> name.

Did you try to enable -free on s390x?  It's a RTL pass.

-- 
Eric Botcazou