[PATCH] D22630: Loop rotation

[Eli Friedman via llvm-commits]

eli.friedman added inline comments.

================
Comment at: llvm/lib/Transforms/Scalar/LoopRotation.cpp:165
@@ -209,5 +164,3 @@
 
-  // Rotate if either the loop latch does *not* exit the loop, or if the loop
-  // latch was just simplified.
-  if (L->isLoopExiting(OrigLatch) && !SimplifiedLatch)
+  if (!isSEME(OrigH, LoopLatch, DT))
     return false;
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Any update on why this check is necessary, or a comment in the code about why it is necessary?

================
Comment at: llvm/lib/Transforms/Scalar/LoopRotation.cpp:319
@@ +318,3 @@
+  // Collect all nodes of the loop from header to latch.
+  BasicBlock *NewH = collectSEMEBlocks(OrigH, OrigLatch, Blocks, Exits);
+  assert(NewH);
----------------
Is it possible this will clone more code?  The trunk version would only clone the header; it looks like this will clone the whole loop body excluding the latch block?


https://reviews.llvm.org/D22630