[llvm] [VPlan] Add specialized VPValue subclasses for different types (NFC) (PR #172758)

[Florian Hahn via llvm-commits]

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@@ -3582,7 +3585,7 @@ class VPCanonicalIVPHIRecipe : public VPHeaderPHIRecipe {
 
   /// Returns the scalar type of the induction.
   Type *getScalarType() const {
-    return getStartValue()->getLiveInIRValue()->getType();
+    return cast<VPLiveIn>(getStartValue())->getValue()->getType();
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fhahn wrote:

Updated, specialized getStartValue and made start value in the constructor also VPLiveIn

https://github.com/llvm/llvm-project/pull/172758