[llvm] [VPlan] Delay adding canonical IV increment. (PR #82270)

[via llvm-commits]

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@@ -91,7 +91,7 @@ bool vputils::isUniformAcrossVFsAndUFs(VPValue *V) {
 
   auto *CanonicalIV = R->getParent()->getPlan()->getCanonicalIV();
   // Canonical IV chain is uniform.
-  if (V == CanonicalIV || V == CanonicalIV->getBackedgeValue())
+  if (V == CanonicalIV) // || V == CanonicalIV->getBackedgeValue())
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ayalz wrote:

Continue to consider the backedge value uniform, if it exists?

https://github.com/llvm/llvm-project/pull/82270