[PATCH] D46801: add getAA in ScheduleDAG for using in HazardRec

[Hal Finkel via Phabricator via llvm-commits]

hfinkel added a comment.

In https://reviews.llvm.org/D46801#1099812, @atrick wrote:

> Atheel,
>
> Just to be clear, you aren't actually using PostRASchedulerList are you?
>
> Once you have contributed a couple sizable patches, you can email Chris Lattner to get commit access.
>
> I could commit this for you, but I just noticed something strange going on. There are two pointers to the current AliasAnalysis, one in ScheduleDAGInstrs and one in ScheduleDAGMI. It looks like they may be set under different conditions. I'm afraid combining them under the same getAA() virtual method may just create more confusion. It looks like Hal was last to work on this.
>
> Hal, can you take a look and commit this in whatever form makes sense to you?


There's an AAForDep because some targets don't want the cost of doing AA queries during instruction scheduling (or no one feels like tracking down the performance regressions we'd see from enabling it (as would be the case on X86 last we looked at this)).

How would this be used?


Repository:
  rL LLVM

https://reviews.llvm.org/D46801