[PATCH] D37343: [CGP] Merge empty case blocks if no extra moves are added.

[Balaram Makam via Phabricator via llvm-commits]

bmakam added a comment.

In https://reviews.llvm.org/D37343#880344, @efriedma wrote:

> > Remove quadratic complexity to calculate DT.
>
> You're still computing DT once for every empty block?


I'm now lazily computing DT only when an empty block can be merged into destination block that have all non-constant incoming phi values. In my tests I found I was computing DT for <10 times. If I have compute DT in eliminateMostlyEmptyBlocks I will be computing for all the blocks even though we might not need them and will have to update the DT whenever an empty block is eliminated.


https://reviews.llvm.org/D37343