[llvm] [VPlan] Support live-ins without underlying IR in type analysis. (PR #80723)

[via llvm-commits]

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@@ -35,6 +36,7 @@ class Type;
 /// of the previously inferred types.
 class VPTypeAnalysis {
   DenseMap<const VPValue *, Type *> CachedTypes;
+  Type *CanonicalIVTy;
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ayalz wrote:

nit: worth a comment what this is for.

https://github.com/llvm/llvm-project/pull/80723