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

[via llvm-commits]

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@@ -3239,7 +3239,8 @@ class VPCanonicalIVPHIRecipe : public VPHeaderPHIRecipe {
 
   VPCanonicalIVPHIRecipe *clone() override {
     auto *R = new VPCanonicalIVPHIRecipe(getOperand(0), getDebugLoc());
-    R->addOperand(getBackedgeValue());
+    if (getNumOperands() == 2)
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ayalz wrote:

Seems reasonable to expect every header phi recipe to have two operands (always) - implementing getStartValue() and getBackedgeValue() of VPHeaderPhiRecipe?

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