Speculative prefetching: report

[Dale Johannesen]

>   Before pushing it to mainline I would like see the
> quadratic bottlenect of bsi_for_stmt resolved.  I don't know where the
> discussion surrounding Zdenek's patch went but I guess without that we
> can fix it by keeping around BSIs instead of direct statement pointers
> in the interface that is straightforward change.

No, I tried that and could not get it to work.  The problem was that 
once
you've expanded one tree nearby stored bsi's become useless.

Besides, storing 3-word bsi's all over the place is not a good thing.