[PATCH] D44199: [LoopRotate] Attempt to Rotate loops if it can lead to removing phi nodes.

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


================
Comment at: lib/Transforms/Scalar/LoopRotation.cpp:181
+    if (llvm::any_of(Phi.users(), [L](const User *U) {
+          return !isa<PHINode>(U) || (isa<Instruction>(U) &&
+                                      L->contains(cast<const Instruction>(U)));
----------------
A user of an Instruction is always an Instruction, so the isa<> is redundant.

This heuristic doesn't seem very general; it's not clear to me why we specifically want to rotate in cases like this, as opposed to peeling or something like that.


https://reviews.llvm.org/D44199