[PATCH] D44983: [LoopUnroll] Only peel if a predicate becomes known in the loop body.

[Max Kazantsev via Phabricator via llvm-commits]

mkazantsev added inline comments.


================
Comment at: lib/Transforms/Utils/LoopUnrollPeel.cpp:200
+    // or !Pred in the loop body statically.
+    unsigned NewPeelCount = DesiredPeelCount;
+
----------------
BTW, I just realized that this entire optimization will be harmful if the predicate is provable for `LeftAR, RightSCEV`. In this case, something is true on EVERY iteration, and you peel out SOME iterations thinking that it would be profitable.

Isn't it the real problem you are trying to win here?


https://reviews.llvm.org/D44983