Loop optimizer issues

[Jason Merrill]

I think there's been a bit of a disconnect in this discussion.

Some people are arguing against merging the rtlopt changes into tree-ssa.
Some people are arguing for merging Zdenek's loop optimizer work into
tree-ssa.

Nobody, AFAICT, is arguing for merging all of rtlopt into tree-ssa.

It seems to me that Zdenek is interested in making his loop optimizer work
at the tree level, and therefore it makes sense to bring it into tree-ssa.

Jason