[PATCH] D39976: [AArch64] Query the target when folding loads and stores

[Geoff Berry via Phabricator via llvm-commits]

gberry added a comment.

In https://reviews.llvm.org/D39976#1017864, @evandro wrote:

> In https://reviews.llvm.org/D39976#1017321, @gberry wrote:
>
> > Would it not be simpler to just add a subtarget bool that controls whether the problematic opcodes are emitted and set it for your subtargets (similar to the way STRQroIsSlow is handled)?  That way you could avoid generating them not just in this pass, but in ISel and frame lowering?
>
>
> Methinks that the gist is to move away from features and to rely more on the cost model.  In the case of this patch, it also removes the feature `FeatureSlowPaired128` in https://reviews.llvm.org/D40107.


That seems like a worthwhile goal, but this change doesn't really seem to be accomplishing that.  If the sched model is being used by a subtarget-specific heuristic, that seems like just a more roundabout way of achieving the same result for your subtarget.  Is there any net effect of this change combined with https://reviews.llvm.org/D40107?


https://reviews.llvm.org/D39976