[llvm] [VPlan] Add new VPInstruction ocpode for header mask. (PR #89603)

[via llvm-commits]

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@@ -2688,14 +2694,13 @@ class VPEVLBasedIVPHIRecipe : public VPHeaderPHIRecipe {
 /// A Recipe for widening the canonical induction variable of the vector loop.
 class VPWidenCanonicalIVRecipe : public VPSingleDefRecipe {
 public:
-  VPWidenCanonicalIVRecipe(VPCanonicalIVPHIRecipe *CanonicalIV)
-      : VPSingleDefRecipe(VPDef::VPWidenCanonicalIVSC, {CanonicalIV}) {}
+  VPWidenCanonicalIVRecipe(VPValue *Start)
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ayalz wrote:

It's still a [Scalar]CanonicalIV, right? `Start` may be confused with the invariant value feeding an IV from the preheader.

https://github.com/llvm/llvm-project/pull/89603