[PATCH] D51703: [LoopInterchange] Move preheader creation to transform stage and simplify.

[Eli Friedman via Phabricator via llvm-commits]

efriedma accepted this revision.
efriedma added a comment.
This revision is now accepted and ready to land.

LGTM



================
Comment at: lib/Transforms/Scalar/LoopInterchange.cpp:1350
+  if (InnerLoopPreHeader == OuterLoop->getHeader())
+    InnerLoopPreHeader = InsertPreheaderForLoop(InnerLoop, DT, LI, true);
+
----------------
Please add a comment explaining that this is using InsertPreheaderForLoop to insert an "extra" preheader block for loops which already have a preheader.


https://reviews.llvm.org/D51703