[PATCH] D79037: [StructurizeCFG] Fix region nodes ordering

[Ehud Katz via Phabricator via llvm-commits]

ekatz marked an inline comment as done.
ekatz added inline comments.


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Comment at: llvm/lib/Transforms/Scalar/StructurizeCFG.cpp:393
+    // Keep processing loops while only going deeper (into inner loops).
+    do {
+      assert(I != POT.rend());
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sameerds wrote:
> ekatz wrote:
> > sameerds wrote:
> > > Why not just have `while (CurrentLoopSize)` here? At least from what I could see, the value should be non-zero when this point is reached from above, right?
> > The problem is that `CurrentLoopSize` may be null in case all of the nodes have a parent loop (none outside from every loop).
> > In that case, `CurrentLoopSize` will only be valid from line 408; and remain that way all the way until the end.
> I am not sure I follow. Can you please rephrase? An example might be useful.
The simplest example is a region without loops. Then the `CurrentLoop` (and in turn, `CurrentLoopSize`) is `nullptr`.


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  https://reviews.llvm.org/D79037/new/

https://reviews.llvm.org/D79037