[PATCH] D54517: [CGP] Limit Complex Addressing mode by number of BasicBlocks to traverse

[Bjorn Pettersson via Phabricator via llvm-commits]

bjope added a comment.

Basically I think the code looks ok. However, I'm not so familiar with this algorithm so it is hard to comment about the actual solution.

My understanding is that you introduce a threshold, and if the size of the TraverseOrder vector grows past the threshold we bail out from findCommon. So what is the impact of this?
I assume it means that we limit the amount of "Complex Addressing mode" optimizations somehow. Is this limit only hit for "large" programs? When compiling a program that hits the threshold, do we lose some optimizations or will the amount of Complex Addressing mode optimizations in such a program be reduced significantly?

How did you choose the current threshold? (that is probably something people want to know when trying to finetune this 4 years from now, so it could be nice to say something about it in the commit msg even if it just is an estimate)


https://reviews.llvm.org/D54517