Identical basic blocks live long in RTL flow.

[Jan Hubicka]

> >
> >Basic blocks 8/9/10 are identical and live until pass jump2, which is
> >after register allocation.
> >I think these duplicated BBs do not contain additional information and
> >should be better to be removed ASAP, because they might interfere with
> >other passes like ifcvt.
> >
> >So should this issue be handled like in jump pass?
> In this case, I'd expect DCE to optimize away the redundant assignments.

Yeah, we also used to be able to optimize these out in crossjumping before
regalloc but with SSA we now produce different pseudos in different copies so I
think it was path by Steven that disabled crossjumping proir jump2 (both passes
also ought to be renamed)

Honza
> 
> 
> 
> jeff