[llvm] [VPlan] Make canonical IV part of the region (PR #156262)

[via llvm-commits]

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@@ -3867,14 +3800,13 @@ class VPEVLBasedIVPHIRecipe : public VPHeaderPHIRecipe {
 class VPWidenCanonicalIVRecipe : public VPSingleDefRecipe,
                                  public VPUnrollPartAccessor<1> {
 public:
-  VPWidenCanonicalIVRecipe(VPCanonicalIVPHIRecipe *CanonicalIV)
+  VPWidenCanonicalIVRecipe(VPRegionValue *CanonicalIV)
       : VPSingleDefRecipe(VPRecipeBase::VPWidenCanonicalIVSC, {CanonicalIV}) {}
 
   ~VPWidenCanonicalIVRecipe() override = default;
 
   VPWidenCanonicalIVRecipe *clone() override {
-    return new VPWidenCanonicalIVRecipe(
-        cast<VPCanonicalIVPHIRecipe>(getOperand(0)));
+    return new VPWidenCanonicalIVRecipe(cast<VPRegionValue>(getOperand(0)));
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ayalz wrote:

May be worth having a getCanonicalIV() which returns the first operand as a RegionValue.

https://github.com/llvm/llvm-project/pull/156262