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

[via llvm-commits]

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@@ -2929,6 +2927,9 @@ class VPlan {
     return BackedgeTakenCount;
   }
 
+  /// Return the backedge taken count of the original loop, if set.
+  VPValue *getBackedgeTakenCount() { return BackedgeTakenCount; }
+
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ayalz wrote:

```suggestion
```
is this still needed?

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