[PATCH] D66287: GlobalISel: add combiner for indexed loads and stores

[Tim Northover via Phabricator via llvm-commits]

t.p.northover added a comment.

> My one concern is with adding the machine dominator analysis the the pipeline at -O0. Is there a significant compile time cost?

Doesn't look like it. I did a few runs of the test-suite, and it came out at maybe 1% difference but the numbers were pretty noisy. I'd be inclined to leave it, though it would certainly be possible to only use MachineDominator at higher levels.

> It's ok if we can pay for it by reducing the amount of code to analyze but we should run the numbers to check.

I doubt this is the kind of optimization that would pay for itself in that way.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D66287/new/

https://reviews.llvm.org/D66287