[llvm] [LoopFusion] Simplifying the legality checks (PR #171889)

[Alireza Torabian via llvm-commits]

================
@@ -174,10 +175,6 @@ struct FusionCandidate {
   /// Has this loop been Peeled
   bool Peeled;
 
-  /// Dominator and PostDominator trees are needed for the
-  /// FusionCandidateCompare function, required by FusionCandidateSet to
-  /// determine where the FusionCandidate should be inserted into the set. These
-  /// are used to establish ordering of the FusionCandidates based on dominance.
   DominatorTree &DT;
   const PostDominatorTree *PDT;
----------------
1997alireza wrote:

Yes. It's used in `nonStrictlyPostDominate` which is called by some of the functions from CodeMoverUtils that loop fusion uses.

https://github.com/llvm/llvm-project/pull/171889