New bootstrap failure on ARM systems

[Richard Earnshaw]

> > It looks to me as though bbro has done a partial recalculation and got it 
> > wrong.
> 
> Hmm, then it must be the cfgcleanup pass just before bbro, as bbro don't
> do any recalculation.

It could be.  I was just going on the rtl dump names.

>  We can perhaps disable the cfgcleanup when ifcvt
> made CE or make it to recompute whole info fron the scratch?

Doesn't the CE pass already do a full recalculation?  If so, it would seem 
that a second one was unnecessary unless further changes were being made.

R.