[PATCH] D133441: [SLP] Look ahead for mutual horizontal reductions.

[Alexey Bataev via Phabricator via llvm-commits]

ABataev added inline comments.


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Comment at: llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp:11035-11038
+    for (ArrayRef<Value *> RdxOps : ReductionOps)
+      for (Value *RdxOp : RdxOps)
+        if (RdxOp)
+          V.addHorizontalReduction(RdxOp);
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Not sure it is a good idea to store reduction ops here, you're working with reduced values actually.


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Comment at: llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp:11778
   SmallPtrSet<Value *, 8> VisitedInstrs;
+  Optional<HorizontalReduction> PendingReduction = None;
   bool Res = false;
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Why do you need this one? In case of successful reduction, the vectorizer restarts the analysis and rebuilds the reduction graph.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D133441/new/

https://reviews.llvm.org/D133441