[PATCH] D33320: [SLP] Improve comments and naming of functions/variables/members, NFC.

[Adam Nemet via Phabricator via llvm-commits]

anemet added inline comments.


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Comment at: lib/Transforms/Vectorize/SLPVectorizer.cpp:4824-4825
+  // vectorization is not possible or not effective, and currently analyzed
+  // instruction is a binary operation, try to vectorize the operands, using DFS
+  // traversal order. If the operands were not vectorized, repeat the same
+  // procedure considering each operand as a possible root of the horizontal
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ABataev wrote:
> anemet wrote:
> > ABataev wrote:
> > > anemet wrote:
> > > > ABataev wrote:
> > > > > anemet wrote:
> > > > > > Again, which order?
> > > > > DFS
> > > > pre/in/post?
> > > pre
> > Okay, then please update the comment.  Also please answer my question below why we chose to track the edges with an iterative pre-order traversal.  If it's unnecessary, please fix or add a FIXME.  Thank you.
> It simplifies limiting the tree traversal level of the function. We can use simple pre-order traversal, but still need to keep the tree node level within the Stack, for example, to limit the recursion level.
I am not sure I see a major difference, do you have an example?


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Comment at: lib/Transforms/Vectorize/SLPVectorizer.cpp:4861
           if (!Inst) {
             P = nullptr;
             continue;
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It would be good to add a comment why we need to clear P beyond the first level.


https://reviews.llvm.org/D33320