[PATCH] D75069: [LoopVectorizer] Inloop vector reductions

[Florian Hahn via Phabricator via llvm-commits]

fhahn added inline comments.


================
Comment at: llvm/lib/Analysis/IVDescriptors.cpp:812
+    if (LHS->getOpcode() == Opcode && L->contains(LHS->getParent()) &&
+        LHS->hasOneUse() &&
+        findPathToPhi(LHS, ReductionOperations, Opcode, Phi, L)) {
----------------
Ayal wrote:
> Looking for a chain of hasOneUse op's would be easier starting from the Phi and going downwards, until reaching LoopExitInstr?
> 
> Note that when extended to handle reductions with conditional bumps, some ops will have more than one use.
Instead of doing a recursive traversal, would it be simpler to just do the traversal iteratively, at least as long as we are only using at  a single use chain?


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https://reviews.llvm.org/D75069