[Patch,tree-optimization]: Add new path Splitting pass on tree ssa representation

[Jeff Law]

On 11/13/2015 11:09 AM, Richard Biener wrote:

>>
>> BTW Do we have an API for indicating that new blocks have been added to
>>
>> a loop?  If so, then we can likely drop the LOOPS_NEED_FIXUP.
>
> Please. It's called add_to_loop or so.
Haha, the block duplication code was handling this already.  So in 
theory I can just drop the LOOPS_NEED_FIXUP completely.  Testing now.

jeff