[PATCH] D86167: [opt][NewPM] Add basic-aa in legacy PM compatibility mode

[Yuanfang Chen via Phabricator via llvm-commits]

ychen accepted this revision.
ychen added inline comments.
This revision is now accepted and ready to land.


================
Comment at: llvm/tools/opt/NewPMDriver.cpp:351
+  // For compatibility with legacy pass manager.
+  // basic-aa was always available in the legacy pass manager,
+  // unless -disable-basic-aa was specified.
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aeubanks wrote:
> ychen wrote:
> > aeubanks wrote:
> > > ychen wrote:
> > > > I think it is helpful to be specific here, saying something like "AAResultsWrapperPass` by default provide basic-aa in legacy PM."
> > > > 
> > > > Could we combine this code with the `if (!AAPipeline.empty())` code above? If the AAPipeline is empty, we could make it "basic-aa".
> > > Added comment.
> > > 
> > > I don't want to change the semantics of any tests using `opt -passes=foo`, this is purely for compatibility with tests using `opt -foo-pass`.
> > > 
> > > And actually I think having to explicitly specify basic-aa makes more sense than implicitly adding it, so I like the NPM way of doing it. But that's a different discussion.
> > That makes sense. Does it mean this code is temporary? i.e once we switch to NPM, we will remove this code and mass-adding `basic-aa` to relevant tests? If so, then sounds good to me.
> I was thinking that would happen alongside whenever we migrate tests to use '-passes='.
Sounds good. Please add a comment about the next step related to this code.

Could you check the empty AAPipeline instead? The code right now is adding `basic-aa` to AAPipeline. 


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D86167/new/

https://reviews.llvm.org/D86167