[llvm] [LoopInterchange] Relax the legality check to accept more patterns (PR #118267)

[Madhur Amilkanthwar via llvm-commits]

madhur13490 wrote:

> Hi @madhur13490 , thanks for your comments!
> 
> > Please note, in #119345, there are discussions about removing "S" dependence.
> 
> Yes, I am aware of the discussion. My implementation doesn't depend on the existence of the `S' dependency, but comments and tests need to be changed after it is removed.
> 
> By the way, I now feel that the `normalize` invocation of dependencies in the `populateDependencyMatrix` is no longer necessary. What do you think?
> 
> https://github.com/llvm/llvm-project/blob/eb71802c422cc337966d25fab726faf9074eb0aa/llvm/lib/Transforms/Scalar/LoopInterchange.cpp#L138-L139

I don't fully understand why `normalize` becomes unnecessary after this patch. Can you please elaborate?
CC @CongzheUalberta 

https://github.com/llvm/llvm-project/pull/118267