[PATCH] D31843: [LCSSA] Try to not walk the dominator tree more than necessary

[Daniel Berlin via Phabricator via llvm-commits]

dberlin added a comment.

In https://reviews.llvm.org/D31843#722830, @mzolotukhin wrote:

> If the slow part is checking if the block dominates any exit, how about we precompute set of blocks meeting this requirement in advance?
>
> E.g. if we start from the set of exiting blocks and go up the dom-tree until we hit the loop header, we should end up with a set of blocks dominating at least one exit.  Would it be faster than what we have now?


This is precisely equivalent to the stack algorithm i outlined.
;)


https://reviews.llvm.org/D31843