[PATCH] D60294: [DAGCombiner] [CodeGenPrepare] WIP/RFC Splitting large offsets from base addresses

Thu Apr 11 16:14:25 PDT 2019

luismarques added a comment.

In D60294#1463517 <https://reviews.llvm.org/D60294#1463517>, @dmgreen wrote:

> Hello. This looks like an interesting patch. Thanks for working on it.  I ran some numbers and on Thumb1 targets (where resources are generally very constrained) this looks like a nice improvement.
>  Things didn't look as good on Thumb2 (and AArch64), but that might be that something isn't tuned correctly, or something that's just going wrong. I'll try and take a look (in the morning). Don't feel that that should block you here, I think something odd might be going on with floating point constants in soft-fp? I'm not sure yet.

My reply through the email seems to have bounced, so I'm quoting it here:
Thanks for the feedback and encouragement. I'm finishing an improved version of the patch, it would be great if you could rerun those analyses on the updated version and share if it changes anything important. The new version properly checks if the transformation would impact the loads/stores that use the constants. I can see that check having an impact on some real-world scenarios not covered by the existing tests.

Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D60294/new/

https://reviews.llvm.org/D60294