[llvm] r290769 - Add a comment for a todo in LoopUnroll post cleanup

[Philip Reames via llvm-commits]

Author: reames
Date: Fri Dec 30 16:10:19 2016
New Revision: 290769

URL: http://llvm.org/viewvc/llvm-project?rev=290769&view=rev
Log:
Add a comment for a todo in LoopUnroll post cleanup


Modified:
    llvm/trunk/lib/Transforms/Utils/LoopUnroll.cpp

Modified: llvm/trunk/lib/Transforms/Utils/LoopUnroll.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/LoopUnroll.cpp?rev=290769&r1=290768&r2=290769&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/LoopUnroll.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/LoopUnroll.cpp Fri Dec 30 16:10:19 2016
@@ -673,6 +673,11 @@ bool llvm::UnrollLoop(Loop *L, unsigned
     }
   }
 
+  // TODO: after peeling or unrolling, previously loop variant conditions are
+  // likely to fold to constants, eagerly propagating those here will require
+  // fewer cleanup passes to be run.  Alternatively, a LoopEarlyCSE might be
+  // appropriate.
+
   NumCompletelyUnrolled += CompletelyUnroll;
   ++NumUnrolled;